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1.
Front Plant Sci ; 14: 1186890, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37409303

RESUMEN

Late stage nitrogen (N) applications following basic fertilization are commonly used to ensure grain yield and increase grain protein content in wheat. Split N applications at the late growth stage of wheat are an effective measure to improve N absorption and transport and thus increase grain protein content. However, whether split N applications can alleviate the decrease in grain protein content induced by elevated atmospheric CO2 concentrations (e[CO2]) remains unclear. In the present study, a free-air CO2 enrichment system was used to investigate the effects of split N applications (at booting or anthesis) on grain yield, N utilization, protein content, and the composition of wheat under atmospheric (ACO2; 400 ± 15 ppm) and elevated CO2 concentrations (ECO2; 600 ± 15 ppm). The results showed that wheat grain yield and grain N uptake increased by 5.0% (being grains per ear by 3.0%, 1000-grain weight by 2.0%, and harvest index by 1.6%) and 4.3%, respectively, whereas grain protein content decreased by 2.3% under ECO2 conditions. Although the negative effect of e[CO2] on grain protein content was not alleviated by split N applications, gluten protein content was enhanced due to the alteration of N distribution in different protein fractions (albumins, globulins, gliadins, and glutenins). Compared to that without split N applications, the gluten content of wheat grains increased by 4.2% and 4.5% when late stage N was applied at the booting stage under ACO2 and anthesis under ECO2 conditions, respectively. The results indicate that rational handling of N fertilizers may be a promising approach to coordinating grain yield and quality under the effects of future climate change. However, compared to ACO2 conditions, the key timing for improving grain quality by split N applications should be postponed from the booting stage to anthesis under e[CO2] conditions.

2.
Comput Methods Programs Biomed ; 238: 107602, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37244234

RESUMEN

BACKGROUND AND OBJECTIVE: Traditional disease diagnosis is usually performed by experienced physicians, but misdiagnosis or missed diagnosis still exists. Exploring the relationship between changes in the corpus callosum and multiple brain infarcts requires extracting corpus callosum features from brain image data, which requires addressing three key issues. (1) automation, (2) completeness, and (3) accuracy. Residual learning can facilitate network training, Bi-Directional Convolutional LSTM (BDC-LSTM) can exploit interlayer spatial dependencies, and HDC can expand the receptive domain without losing resolution. METHODS: In this paper, we propose a segmentation method by combining BDC-LSTM and U-Net to segment the corpus callosum from multiple angles of brain images based on computed tomography (CT) and magnetic resonance imaging (MRI) in which two types of sequence, namely T2-weighted imaging as well as the Fluid Attenuated Inversion Recovery (Flair), were utilized. The two-dimensional slice sequences are segmented in the cross-sectional plane, and the segmentation results are combined to obtain the final results. Encoding, BDC- LSTM, and decoding include convolutional neural networks. The coding part uses asymmetric convolutional layers of different sizes and dilated convolutions to get multi-slice information and extend the convolutional layers' perceptual field. RESULTS: This paper uses BDC-LSTM between the encoding and decoding parts of the algorithm. On the image segmentation of the brain in multiple cerebral infarcts dataset, accuracy rates of 0.876, 0.881, 0.887, and 0.912 were attained for the intersection of union (IOU), dice similarity coefficient (DS), sensitivity (SE), and predictive positivity value (PPV). The experimental findings demonstrate that the algorithm outperforms its rivals in accuracy. CONCLUSION: This paper obtained segmentation results for three images using three models, ConvLSTM, Pyramid-LSTM, and BDC-LSTM, and compared them to verify that BDC-LSTM is the best method to perform the segmentation task for faster and more accurate detection of 3D medical images. We improve the convolutional neural network segmentation method to obtain medical images with high segmentation accuracy by solving the over-segmentation problem.


Asunto(s)
Cuerpo Calloso , Procesamiento de Imagen Asistido por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Cuerpo Calloso/diagnóstico por imagen , Estudios Transversales , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X
3.
BMC Psychiatry ; 23(1): 217, 2023 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-36997897

RESUMEN

BACKGROUND: Previous studies have shown that insomnia affects human prefrontal function and that there are specific patterns of brain activation to counteract sleep and improve cognition. However, the effects of insomnia on the prefrontal cortex of MDD (major depressive disorder) patients and the patterns of activation to counteract sleep in MDD patients remain unclear. The aim of this study is to examine this using fNIRS (functional near-infrared spectroscopy). METHODS: Eighty depressed patients and 44 healthy controls were recruited for this study. fNIRS was used to assess changes in the concentration of oxygenated hemoglobin ([oxy-Hb]) in the prefrontal cortex of all participants during the VFT (verbal fluency test) and to record the number of words created to assess cognitive ability. The Pittsburgh Sleep Quality Index was used to assess sleep quality, and the Hamilton Rating Scale for Depression (24-item) and Hamilton Rating Scale for Anxiety (14-item) were used to assess the severity of depression and anxiety. RESULTS: When comparing patients, the healthy control group had significantly higher [oxy-Hb] values in the bilateral prefrontal cortex during VFT than the MDD group. In the MDD group, the [oxy-Hb] values in all brain regions except the right DLPFC were significantly higher in the group with insomnia than in the group without insomnia, but their VFT performance was significantly lower than in the group without insomnia and the healthy group. PSQI scores were positively correlated with [oxy-Hb] values in some left-brain regions, whereas HAMD and HAMA scores were not correlated with [oxy-Hb] values. CONCLUSION: The PFC was significantly less active during VFT in those with MDD than in healthy controls. All brain regions, except the right DLPFC, were significantly more active in MDD patients with insomnia than in those without insomnia, suggesting that sleep quality needs to be an important indicator in fNIRS screening. In addition, there was a positive correlation between the severity of insomnia in the left VLPFC and the level of activation, suggesting a role for the left brain region in the neurophysiology of overcoming sleepiness in MDD patients. these findings may provide new ideas for the treatment of MDD patients in the future. TRIAL REGISTRATION: Our experiment was registered in the China Clinical Trial Registry (registration number ChiCTR2200065622) on November 10.( The first patient was recruited in 10/11/2022.).


Asunto(s)
Trastorno Depresivo Mayor , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Ansiedad , Depresión , Trastorno Depresivo Mayor/diagnóstico , Corteza Prefrontal/diagnóstico por imagen , Espectroscopía Infrarroja Corta/métodos , Trastornos del Inicio y del Mantenimiento del Sueño/complicaciones
4.
Comput Methods Programs Biomed ; 229: 107304, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36586176

RESUMEN

OBJECTIVE: The traditional ICM is widely used in applications, such as image edge detection and image segmentation. However, several model parameters must be set, which tend to lead to reduced accuracy and increased cost. As medical images have more complex edges, contours and details, more suitable combinatorial algorithms are needed to handle the pathological diagnosis of multiple cerebral infarcts and acute strokes, resulting in the findings being more applicable, as well as having good clinical value. METHODS: To better solve the medical image fusion and diagnosis problems, this paper introduces the image fusion algorithm based on the combination of NSCT and improved ICM and proposes low-frequency, sub-band fusion rules and high-frequency sub-band fusion rules. The above method is applied to the fusion of CT/MRI images, subsequently, three other fusion algorithms, including NSCT-SF-PCNN, NSCT-SR-PCNN and Adaptive-PCNN are compared, and the simulation results of image fusion are analyzed and validated. RESULTS: According to the experimental findings, the suggested algorithm performs better than other fusion algorithms in terms of five objective evaluation metrics or subjective evaluation. The NSCT transform and the improved ICM were combined, and the outcomes were evaluated against those of other fusion algorithms. The CT/MRI medical images of healthy brain tissue, numerous cerebral infarcts and acute strokes were combined using this technique. CONCLUSION: Medical image fusion using Adaptive-PCNN produces satisfactory results, not only in relation to improved image clarity but also in terms of outstanding edge information, high contrast and brightness.


Asunto(s)
Accidente Cerebrovascular , Corteza Visual , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Redes Neurales de la Computación , Algoritmos , Accidente Cerebrovascular/diagnóstico por imagen , Infarto Cerebral/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos
5.
Ying Yong Sheng Tai Xue Bao ; 32(8): 2818-2828, 2021 Aug.
Artículo en Chino | MEDLINE | ID: mdl-34664455

RESUMEN

Taking the main production area of yam in North China Plain as the research area, we analyzed the status of soil fertility and fertilizer application in yam production through field investigation and tracking monitoring, examined soil nutrient balance using the input-output model of nutrients in agricultural system, and assessed the environmental risks in the yam planting system. The results showed that: 1) the contents of soil organic matter and total N were extremely low, and the contents of available P and available Zn were both low; both nitrate and available Cu contents were at the middle level, the contents of soil slowly available K, available S, and exchangeable Ca and Mg were all extremely high, the contents of available K, available Fe, and available Mn were all at high level; 2) The nitrogen (N), phosphorus (P2O5), and potassium (K2O) inputs were 575-943 kg·hm-2, 341-981 kg·hm-2, and 655-1219 kg·hm-2 during the whole growth period of yam, with chemical fertilizer accounting for 83.0%, 88.6%, and 91.3%, respectively; The input imbalance between organic and inorganic fertilizer, as well as the excessive nutrients input were prominent; 3) The surplus rate of soil nitrogen, phosphorus and potassium reached 271.14 kg·hm-2, 466.34 kg·hm-2, and 739.97 kg·hm-2, with corresponding surplus ratio of 48.7%, 258.1%, and 324.5%, respectively, which all exceeded the environmental safety threshold and were classified as moderate risk, severe risk, and severe risk, respectively. The overall environmental risk caused by chemical fertilizer application in yam production had reached severe risk level.


Asunto(s)
Dioscorea , Suelo , China , Nutrientes , Medición de Riesgo
6.
Comput Methods Programs Biomed ; 211: 106410, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34587563

RESUMEN

PURPOSE: The characteristics of children's reading interest, stimulated by the visual evoked potentials of colour graphics in children's picture books, were tested to explore their normal reference value. The characteristics of chromatic pattern visual evoked potential (CP-VEP) can be harnessed by our methodology and may be applied to the visual screening of children in clinical ophthalmology. METHODS: The PR-650 spectral colour metre can strictly control factors, such as brightness and colour retention, based on colour contrast. This is performed in order to reduce the brightness contrast method. In our paper, we set up three kinds of visual stimulation conditions and performed CP-VEP inspections of the eye, based on 64 cases (128 eyes) of normal children (32 males and 32 females). Using CP-VEP detection, the latency and amplitude of the P100 wave were recorded and the waveforms of each group, under different spectral modes were compared. Art therapy combined with children's colour physiology and psychology will be more skilfully practiced in clinical practice. RESULTS: There was no significant difference in the amplitude and peak time of visual evoked potential (VEP) waveforms between the left and right eyes of the children using the three stimuli, indicating that the visual function and visual conduction pathway of children can vary. There was no significant difference in the latency and amplitude of the NPN complex wave. Note that the P1 wave of the right and left eyes of normal children is not statistically different (P > 0.05). We also found that there is insignificant difference in the visual impact of the colours for both male and female children in terms of reading interest, and red is a more stimulating colour for both sexes. CONCLUSION: Our study can provide normal reference value and methodological reference for clinical visual acuity detection in children. Combined with the visual characteristics of children, this paper selects the visual impact created by the colour of picture books and combines it with medical treatment. Make the whole test cover the scope of ophthalmology clinical more comprehensive.


Asunto(s)
Potenciales Evocados Visuales , Lectura , Biometría , Niño , Femenino , Humanos , Masculino , Estimulación Luminosa , Vías Visuales
7.
PLoS One ; 8(7): e70739, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23936246

RESUMEN

Agroforestry has been widely practiced in the Loess Plateau region of China because of its prominent effects in reducing soil and water losses, improving land-use efficiency and increasing economic returns. However, the agroforestry practices may lead to competition between crops and trees for underground soil moisture and nutrients, and the trees on the canopy layer may also lead to shortage of light for crops. In order to minimize interspecific competition and maximize the benefits of tree-based intercropping systems, we studied photosynthesis, growth and yield of soybean (Glycine max L. Merr.) and peanut (Arachis hypogaea L.) by measuring photosynthetically active radiation, net photosynthetic rate, soil moisture and soil nutrients in a plantation of apple (Malus pumila M.) at a spacing of 4 m × 5 m on the Loess Plateau of China. The results showed that for both intercropping systems in the study region, soil moisture was the primary factor affecting the crop yields followed by light. Deficiency of the soil nutrients also had a significant impact on crop yields. Compared with soybean, peanut was more suitable for intercropping with apple trees to obtain economic benefits in the region. We concluded that apple-soybean and apple-peanut intercropping systems can be practical and beneficial in the region. However, the distance between crops and tree rows should be adjusted to minimize interspecies competition. Agronomic measures such as regular canopy pruning, root barriers, additional irrigation and fertilization also should be applied in the intercropping systems.


Asunto(s)
Arachis/fisiología , Productos Agrícolas/fisiología , Glycine max/fisiología , Malus/fisiología , Raíces de Plantas/fisiología , Árboles/fisiología , Agricultura/métodos , Biomasa , China , Humanos , Luz , Fotosíntesis/fisiología , Suelo/química , Agua/fisiología
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