Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Front Plant Sci ; 15: 1367738, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38863551

RESUMEN

Currently, foliar diseases of chili have significantly impacted both yield and quality. Despite effective advancements in deep learning techniques for the classification of chili leaf diseases, most existing classification models still face challenges in terms of accuracy and practical application in disease identification. Therefore, in this study, an optimized and enhanced convolutional neural network model named MCCM (MCSAM-ConvNeXt-MSFFM) is proposed by introducing ConvNeXt. The model incorporates a Multi-Scale Feature Fusion Module (MSFFM) aimed at better capturing disease features of various sizes and positions within the images. Moreover, adjustments are made to the positioning, activation functions, and normalization operations of the MSFFM module to further optimize the overall model. Additionally, a proposed Mixed Channel Spatial Attention Mechanism (MCSAM) strengthens the correlation between non-local channels and spatial features, enhancing the model's extraction of fundamental characteristics of chili leaf diseases. During the training process, pre-trained weights are obtained from the Plant Village dataset using transfer learning to accelerate the model's convergence. Regarding model evaluation, the MCCM model is compared with existing CNN models (Vgg16, ResNet34, GoogLeNet, MobileNetV2, ShuffleNet, EfficientNetV2, ConvNeXt), and Swin-Transformer. The results demonstrate that the MCCM model achieves average improvements of 3.38%, 2.62%, 2.48%, and 2.53% in accuracy, precision, recall, and F1 score, respectively. Particularly noteworthy is that compared to the original ConvNeXt model, the MCCM model exhibits significant enhancements across all performance metrics. Furthermore, classification experiments conducted on rice and maize disease datasets showcase the MCCM model's strong generalization performance. Finally, in terms of application, a chili leaf disease classification website is successfully developed using the Flask framework. This website accurately identifies uploaded chili leaf disease images, demonstrating the practical utility of the model.

2.
Schizophr Res ; 269: 123-129, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38772324

RESUMEN

BACKGROUND: Persistent auditory verbal hallucinations (pAVHs) are a fundamental manifestation of schizophrenia (SCZ), yet the exact connection between pAVHs and brain structure remains contentious. This study aims to explore the potential correlation between pAVHs and alterations in grey matter volume (GMV) within specific brain regions among individuals diagnosed with SCZ. METHODS: 76 SCZ patients with pAVHs (pAVH group), 57 SCZ patients without AVHs (non-AVH group), and 83 healthy controls (HC group) were investigated using 3 T magnetic resonance imaging. The P3 hallucination item of the Positive and Negative Syndrome Scale was used to assess the severity of pAVHs. Voxel-based morphometry was used to analyze the GMV profile between the three groups. RESULTS: Compared to the non-AVH and HC groups, the pAVH group exhibited extensive reduction in GMV within the frontotemporal cortex. Conversely, no significant difference in GMV was observed between the non-AVH and HC groups. The severity of pAVHs showed a negative correlation with GMV in several regions, including the right fusiform, right inferior temporal, right medial orbitofrontal, right superior frontal, and right temporal pole (p = 0.0036, Bonferroni correction). Stepwise linear regression analysis revealed that GMV in the right temporal pole (ß = -0.29, p = 0.001) and right fusiform (ß = -0.21, p = 0.01) were significantly associated with the severity of pAVHs. CONCLUSIONS: Widespread reduction in GMV is observed within the frontotemporal cortex, particularly involving the right temporal pole and right fusiform, which potentially contribute to the pathogenesis of pAVHs in individuals with chronic SCZ.


Asunto(s)
Sustancia Gris , Alucinaciones , Imagen por Resonancia Magnética , Esquizofrenia , Lóbulo Temporal , Humanos , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/patología , Alucinaciones/diagnóstico por imagen , Alucinaciones/etiología , Alucinaciones/patología , Alucinaciones/fisiopatología , Masculino , Femenino , Adulto , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/patología , Enfermedad Crónica , Lóbulo Frontal/diagnóstico por imagen , Lóbulo Frontal/patología , Persona de Mediana Edad , Adulto Joven , China , Pueblos del Este de Asia
3.
Schizophr Bull ; 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38577952

RESUMEN

BACKGROUND AND HYPOTHESIS: Persistent auditory verbal hallucinations (pAVHs) and olfactory identification impairment are common in schizophrenia (SCZ), but the neuroimaging mechanisms underlying both pAVHs and olfactory identification impairment are unclear. This study aimed to investigate whether pAVHs and olfactory identification impairment in SCZ patients are associated with changes in cortical thickness. STUDY DESIGN: In this study, cortical thickness was investigated in 78 SCZ patients with pAVHs (pAVH group), 58 SCZ patients without AVHs (non-AVH group), and 83 healthy controls (HC group) using 3T magnetic resonance imaging. The severity of pAVHs was assessed by the Auditory Hallucination Rating Scale. Olfactory identification deficits were assessed using the Odor Stick Identification Test for Japanese (OSIT-J). In addition, the relationship between the severity of pAVHs and olfactory identification disorder and cortical thickness abnormalities was determined. STUDY RESULTS: Significant reductions in cortical thickness were observed in the right medial orbital sulcus (olfactory sulcus) and right orbital sulcus (H-shaped sulcus) in the pAVH group compared to both the non-AVH and HC groups (P < .003, Bonferroni correction). Furthermore, the severity of pAVHs was found to be negatively correlated with the reduction in cortical thickness in the olfactory sulcus and H-shaped sulcus. Additionally, a decrease in cortical thickness in the olfactory sulcus showed a positive correlation with the OSIT-J scores (P < .05, false discovery rate correction). CONCLUSIONS: Cortical thickness abnormalities in the olfactory sulcus may be a common neuroimaging mechanism for pAVHs and olfactory identification deficits in SCZ patients.

4.
BMC Psychiatry ; 24(1): 248, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38566016

RESUMEN

BACKGROUND: Glutamatergic function abnormalities have been implicated in the etiology of treatment-resistant schizophrenia (TRS), and the efficacy of clozapine may be attributed to its impact on the glutamate system. Recently, evidence has emerged suggesting the involvement of immune processes and increased prevalence of antineuronal antibodies in TRS. This current study aimed to investigate the levels of multiple anti-glutamate receptor antibodies in TRS and explore the effects of clozapine on these antibody levels. METHODS: Enzyme linked immunosorbent assay (ELISA) was used to measure and compare the levels of anti-glutamate receptor antibodies (NMDAR, AMPAR, mGlur3, mGluR5) in clozapine-treated TRS patients (TRS-C, n = 37), clozapine-naïve TRS patients (TRS-NC, n = 39), and non-TRS patients (nTRS, n = 35). Clinical symptom severity was assessed using the Positive and Negative Symptom Scale (PANSS), while cognitive function was evaluated using the MATRICS Consensus Cognitive Battery (MCCB). RESULT: The levels of all four glutamate receptor antibodies in TRS-NC were significantly higher than those in nTRS (p < 0.001) and in TRS-C (p < 0.001), and the antibody levels in TRS-C were comparable to those in nTRS. However, no significant associations were observed between antibody levels and symptom severity or cognitive function across all three groups after FDR correction. CONCLUSION: Our findings suggest that TRS may related to increased anti-glutamate receptor antibody levels and provide further evidence that glutamatergic dysfunction and immune processes may contribute to the pathogenesis of TRS. The impact of clozapine on anti-glutamate receptor antibody levels may be a pharmacological mechanism underlying its therapeutic effects.


Asunto(s)
Antipsicóticos , Clozapina , Esquizofrenia , Humanos , Clozapina/efectos adversos , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/diagnóstico , Esquizofrenia Resistente al Tratamiento , Receptores de Glutamato/uso terapéutico , Ácido Glutámico , Antipsicóticos/efectos adversos
5.
Biomimetics (Basel) ; 9(4)2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38667235

RESUMEN

Soil adhesion is one of the important factors affecting the working stability and quality of agricultural machinery. The application of bionic non-smooth surfaces provides a novel idea for soil anti-adhesion. The parameters of sandy loam with 21% moisture content were calibrated by the Engineering Discrete Element Method (EDEM). The final simulated soil repose angle was highly consistent with the measured soil repose angle, and the obtained regression equation of the soil repose angle provides a numerical reference for the parameter calibration of different soils. By simulating the sinusoidal swing of a sandfish, it was found that the contact interface shows the phenomenon of stress concentration and periodic change, which reflects the effectiveness of flexible desorption and soil anti-adhesion. The moving resistance of the wedge with different wedge angles and different serrated structures was simulated. Finally, it was found that a 40° wedge with a high-tail sparse staggered serrated structure on the surface has the best drag reduction effect, and the drag reduction is about 10.73%.

6.
Sci Rep ; 14(1): 760, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38191904

RESUMEN

Accurate and comprehensive extraction of water bodies facilitates the study of watershed changes and water quality monitoring and also provides a reference for ecological evolution. When extracting tributaries and small water bodies based on remote sensing images, there are problems such as uncertain threshold selection, more edge voids, and extraction difficulties. The improved water body extraction method (Combination Normalized Difference Water Index), fuses Digital Elevation Model and remote sensing images. The river network is extracted from the Digital Elevation Model and the remote sensing image is normalized. After fusion, threshold comparison is performed, and the threshold of the river network location is used as the basis for connecting the broken water bodies, it is compared and verified with the normalized thresholds to achieve accurate identification and complete extraction of water bodies. Taking the water bodies in Xinyang City as an example, the overall accuracy of the confusion matrix was the highest, with an overall accuracy of 93.0% compared with the traditional index method. Combined with water bodies in Zhengzhou City for model validation, it has high applicability. Whether the water body is large or small, the extraction results are complete, with no voids or broken, and the accuracy is high.

7.
Biomech Model Mechanobiol ; 23(3): 861-877, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38261094

RESUMEN

The research on the crack propagation mechanism of bone has important research significance and clinical medical value for the selection of cutting parameters and the development of new surgical tools. In this paper, an extended finite element method (X-FEM) model of ultrasonic bone cutting considering microstructure was developed to further study the ultrasonic bone cutting mechanism and to quantitatively analyze the effects of cutting direction, ultrasonic parameters, and cutting parameters on the mechanism of ultrasonic bone cutting crack propagation. The results show that ultrasonic bone cutting is essentially a controlled crack propagation process, in which brittle crack and fatigue crack are the main crack propagation mechanisms. In order to improve the efficiency of ultrasonic bone cutting, large amplitude and high-frequency ultrasonic vibration are preferred. Compared with the other two cutting directions, the crack propagation deflection angle in the transverse cutting direction is the largest, resulting in the worst cutting surface. Therefore, in the path planning of orthopedic surgical robots, the transverse cutting direction should be avoided as much as possible. Frequency only has a significant effect on the crack propagation rate and has a positive correlation. There is a positive correlation between the deflection angle, propagation length, propagation rate, and amplitude, which provides the possibility to control the direction and length of crack propagation by controlling the amplitude of ultrasonic. The feed speed is much lower than the ultrasonic vibration speed, which makes the influence of ultrasonic vibration speed on the crack propagation characteristics dominant. The X-FEM model of ultrasonic bone cutting provides an effective method for selecting reasonable machining parameters of orthopedic robot and optimize the design of ultrasonic osteotome.


Asunto(s)
Huesos , Análisis de Elementos Finitos , Huesos/fisiología , Vibración , Humanos , Ondas Ultrasónicas , Ultrasonido , Simulación por Computador , Estrés Mecánico
9.
BMC Psychiatry ; 23(1): 580, 2023 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-37563573

RESUMEN

BACKGROUND: Depressive and anxiety symptoms affect about one-fourth of Chinese secondary school students. However, the prevalence and correlates of mental distress among secondary school students from Western China remain largely unexplored. This study aimed to examine the prevalence and associations of depressive and anxiety symptoms with demographic, family, school, life, and behavior factors in a large, representative sample of secondary school students in Zigong, a city in Western China. METHODS: Secondary school students were recruited using cluster sampling. The 9-item Patient Health Questionnaire, the 7-item Generalized Anxiety Disorder Questionnaire, Multidimensional Peer-Victimization Scale, the Pittsburgh Sleep Quality Index, and Nine-Item Internet Gaming Disorder Scale-Short Form were used. Descriptive statistic was used to describe the sociodemographic characteristics of participants. The clustering effect was adjusted by the "survey" package of R to calculate weighted prevalence. Univariate and multivariate logistic regression were used to explore associated factors of depression and anxiety, respectively. RESULTS: A total of 63,205 participants were involved, in which the weighted prevalence of depression in all subjects was 23.0% (95% CI: 19.6- 27.0%), and the weighted prevalence of anxiety was 13.9% (95% CI: 11.2- 17.0%). Logistic regression results showed girls, being single-child, non-nuclear family, peer bullying, sleep disturbance, and internet gaming disorder symptoms were positively associated with depressive and anxiety symptoms. CONCLUSION: Depressive and anxiety symptoms were prevalent among secondary school students in Western China. Our results can guide policy strategies for the assessment, prevention, and intervention of psychological status among Chinese secondary school students.


Asunto(s)
Depresión , Pueblos del Este de Asia , Femenino , Humanos , Depresión/epidemiología , Depresión/psicología , Prevalencia , Ansiedad/epidemiología , Ansiedad/psicología , Estudiantes/psicología , Instituciones Académicas , China/epidemiología
10.
BMC Psychiatry ; 23(1): 470, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37370004

RESUMEN

BACKGROUND: Low-grade inflammation and altered inflammatory markers have been observed in treatment-resistant schizophrenia (TRS). Interleukin-6 (IL-6) is one of the pro-inflammatory cytokines linked with TRS and receives increasing attention. Previous studies showed that patients with TRS might have higher IL-6 levels compared with healthy individuals and treatment-responsive patients. Besides, emerging evidence has suggested that there are sex differences in the associations between IL-6 levels and various illnesses, including chronic hepatitis C, metabolic syndrome, etc.; however, there is limited study on TRS. In this present study, we aimed to compare the serum IL-6 levels of TRS and partially responsive schizophrenia (PRS) and explore potential sex differences in the association of TRS and IL-6 levels. METHODS: The study population consisted of a total of 90 patients with schizophrenia: 64 TRS patients (45.3% males and 54.7% females) and 26 PRS patients (46.2% males and 53.8% females). We measured serum IL-6 levels using enzyme-linked immunosorbent assay (ELISA) and analyzed them separately by gender, controlling for confounders (age, education, medication, body mass index, and PANSS scores) rigorously. RESULT: The results showed that patients with TRS had higher serum IL-6 levels than patients with PRS (p = 0.002). In females, IL-6 levels increased significantly in the TRS group compared with the PRS group (p = 0.005). And a positive correlation tendency was observed between IL-6 levels and PANSS general sub-scores (r = 0.31, p = 0.039), although this correlation was not significant after correcting for multiple comparisons. Whereas, there were no differences in IL-6 levels between the TRS and PRS (p = 0.124) in males. CONCLUSION: Our findings provided evidence supporting the hypothesis that the inflammatory response system (IRS) may play a role in the pathogenesis of TRS in a sex-dependent manner. In addition, sex differences in the immune dysfunction of individuals with schizophrenia cannot be neglected, and inflammation in male and female TRS should be discussed separately.


Asunto(s)
Esquizofrenia , Femenino , Humanos , Masculino , Inflamación , Interleucina-6 , Esquizofrenia/tratamiento farmacológico , Esquizofrenia Resistente al Tratamiento , Caracteres Sexuales
11.
Eur Arch Psychiatry Clin Neurosci ; 273(8): 1813-1824, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36949249

RESUMEN

Olfactory discrimination dysfunction has been observed in patients with schizophrenia (SCZ), but its relationship with cognitive function has not been clarified. The purpose of this study was to examine the differences in olfactory identification function in SCZ patients with and without auditory verbal hallucinations (AVHs) and its relationship with cognitive function. Olfactory identification function was measured in 80 SCZ patients with AVHs, 57 SCZ patients without AVHs, and 87 healthy controls (HC). Clinical symptom scores and neuropsychological measures were also administered to all corresponding subjects. Compared to HC, SCZ patients showed significant deficits in olfactory identification and cognitive function, but there were no differences in olfactory identification dysfunction and cognitive dysfunction between the two subgroups. In the non-AVHs subgroup only, poorer Olfactory Stick Identification Test for Japanese (OSIT-J) scores were significantly and positively correlated with total and delayed recall (Bonferroni correction, p < 0.002). Stepwise regression analysis revealed that factors affecting olfactory identification impairment differed in the two SCZ patient subgroups. In conclusion, this study highlights the commonality of olfactory identification dysfunction in SCZ patients and the importance of olfactory assessment of different subtypes of SCZ patients.


Asunto(s)
Trastornos del Olfato , Esquizofrenia , Humanos , Alucinaciones , Cognición , Trastornos del Olfato/etiología
12.
Hum Brain Mapp ; 44(2): 304-314, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35838008

RESUMEN

Methamphetamine use disorder (MUD) has been associated with broad neurocognitive impairments. While the cognitive impairments of MUD have been demonstrated, the neuropathological underpinnings remain inadequately understood. To date, the published human diffusion tensor imaging (DTI) studies involving the correlation between diffusion parameters and neurocognitive function in MUD are limited. Hence, the present study aimed to examine the association between cognitive performance and white matter microstructure in patients with MUD. Forty-five patients with MUD and 43 healthy controls (HCs) completed their demographic information collection, cognitive assessments, and DTI imaging. DTI images were preprocessed to extract fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) of various fiber tracts. Univariate tests were used to examine group differences in cognitive assessments and DTI metrics. Linear regression was used to examine the relationship between these two metrics. The results revealed that patients with MUD had lower subset scores of the MATRICS Consensus Cognitive Battery (MCCB), which reflects five cognitive domains: processing speed, attention, verbal learning, visual learning, problem-solving. Patients with MUD also had significantly higher AD, MD, and RD values of the left superior longitudinal fasciculus than HCs. Furthermore, the RD value of the left superior longitudinal fasciculus was a significant predictor of processing speed and problem-solving ability, as shown by the digit-symbol coding test and NAB-Mazes scores, respectively. Findings extended our understanding of white matter microstructure that is related to neurocognitive deficits in MUD and provided potential targets for the prevention and treatment of this chronic disorder.


Asunto(s)
Metanfetamina , Sustancia Blanca , Humanos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Imagen de Difusión Tensora/métodos , Metanfetamina/efectos adversos , Cognición
13.
Asian J Psychiatr ; 80: 103416, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36577325

RESUMEN

The aim of this study was to investigate the relationship between persistent auditory verbal hallucinations (pAVHs) and N-acetyl-aspartate (NAA) levels in posterior cingulate cortex (PCC). 117 schizophrenia (SCZ) patients (61 pAVHs and 56 non-AVHs) and 66 healthy controls were included. The P3 item of the Positive and Negative Syndrome Scale and the Auditory Hallucinations subscale of the Psychotic Symptom Rating Scale were used to assess the severity of pAVHs. NAA levels were significantly lower in the AVHs group, and were negatively correlated with pAVHs. Therefore, increasing the NAA levels in PCC may be helpful in treating pAVHs.


Asunto(s)
Esquizofrenia , Humanos , Esquizofrenia/complicaciones , Esquizofrenia/diagnóstico , Giro del Cíngulo/diagnóstico por imagen , Ácido Aspártico , Pueblos del Este de Asia , Alucinaciones/etiología , Alucinaciones/diagnóstico , Imagen por Resonancia Magnética
14.
Front Psychiatry ; 13: 977538, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36578297

RESUMEN

Background: Individuals who experience the prodromal phase of schizophrenia (SCZ), a common and complex psychiatric disorder, are referred to as ultra-high-risk (UHR) individuals. Short-chain fatty acid (SCFA) is imperative in the microbiota-gut-brain axis and brain function. Accumulating amount of evidence shows the connections between psychiatric disorders and SCFAs. This study aims to explore the underlying roles SCFAs play in SCZ by investigating the association of alterations in SCFAs concentrations with common cognitive functions in both the SCZ and UHR populations. Methods: The study recruited 59 SCZ patients (including 15 participants converted from the UHR group), 51 UHR participants, and 40 healthy controls (HC) within a complete follow-up of 2 years. Results of cognitive functions, which were assessed by utilizing HVLT-R and TMT, and serum concentrations of SCFAs were obtained for all participants and for UHR individuals at the time of their conversion to SCZ. Results: Fifteen UHR participants converted to SCZ within a 2-year follow-up. Valeric acid concentration levels were lower in both the baseline of UHR individuals whom later converted to SCZ (p = 0.046) and SCZ patients (p = 0.036) than the HC group. Additionally, there were lower concentrations of caproic acid in the baseline of UHR individuals whom later transitioned to SCZ (p = 0.019) and the UHR group (p = 0.016) than the HC group. Furthermore, the caproic acid levels in the UHR group are significantly positively correlated with immediate memory (r = 0.355, p = 0.011) and negatively correlated with TMT-B (r = -0.366, p = 0.009). Significant differences in levels of acetic acid, butyric acid and isovaleric acid were absent among the three groups and in UHR individuals before and after transition to SCZ. Conclusion: Our study suggests that alterations in concentrations of SCFAs may be associated with the pathogenesis and the cognitive impairment of schizophrenia. Further researches are warranted to explore this association. The clinical implications of our findings were discussed.

15.
Front Mol Neurosci ; 15: 845970, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35645736

RESUMEN

Auditory verbal hallucinations (AVHs) are one of the most common and severe symptoms of schizophrenia (SCZ), but the neuroanatomical mechanisms underlying AVHs remain unclear. This study aimed to investigate whether persistent AVHs (pAVH) are associated with cortical thinning of certain brain regions in patients with SCZ. With the use of the 3T magnetic resonance imaging (MRI) technology, we acquired and analyzed data from 79 SCZ patients with pAVH (pAVH group), 60 SCZ patients without AVHs (non-AVH group), and 83 healthy controls (HC group). The severity of pAVH was assessed by the P3 hallucination items in the Positive and Negative Syndrome Scale (PANSS) and the Auditory Hallucinations Rating Scale (AHRS). Cortical thickness analysis was used to compare the region of interest (ROI) cortical thickness between the groups. The relationship between the severity of pAVH and cortical thickness was also explored. Compared with the non-AVH and HC groups, the pAVH group exhibited significantly reduced cortical thickness in the bilateral lateral orbitofrontal region (p < 0.0007, after Bonferroni correction); no significant difference was found between the non-AVH group and the HC group. The cortical thickness of the left lateral orbitofrontal cortex (P3: r = -0.44, p < 0.001; AHRS: r = -0.45, p < 0.001) and the right lateral orbitofrontal cortex (P3: r = -0.36, p = 0.002; AHRS: r = -0.33, p = 0.004) were negatively correlated with the severity of pAVH (after Bonferroni correction, p < 0.0125). Therefore, abnormal thickness of the bilateral lateral orbitofrontal cortices might be associated with pAVHs in SCZ patients.

16.
Front Neurosci ; 16: 831714, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35495040

RESUMEN

It has been claimed that individuals with schizophrenia have difficulty in self-recognition and, consequently, are unable to identify the sources of their sensory perceptions or thoughts, resulting in delusions, hallucinations, and unusual experiences of body ownership. The deficits also contribute to the enhanced rubber hand illusion (RHI; a body perception illusion, induced by synchronous visual and tactile stimulation). Evidence based on RHI paradigms is emerging that auditory information can make an impact on the sense of body ownership, which relies on the process of multisensory inputs and integration. Hence, we assumed that auditory verbal hallucinations (AVHs), as an abnormal auditory perception, could be linked with body ownership, and the RHI paradigm could be conducted in patients with AVHs to explore the underlying mechanisms. In this study, we investigated the performance of patients with/without AVHs in the RHI. We administered the RHI paradigm to 80 patients with schizophrenia (47 with AVHs and 33 without AVHs) and 36 healthy controls. We conducted the experiment under two conditions (synchronous and asynchronous) and evaluated the RHI effects by both objective and subjective measures. Both patient groups experienced the RHI more quickly and strongly than HCs. The RHI effects of patients with AVHs were significantly smaller than those of patients without AVHs. Another important finding was that patients with AVHs did not show a reduction in RHI under asynchronous conditions. These results emphasize the disturbances of the sense of body ownership in schizophrenia patients with/without AVHs and the associations with AVHs. Furthermore, it is suggested that patients with AVHs may have multisensory processing dysfunctions and internal timing deficits.

17.
ACS Appl Mater Interfaces ; 14(17): 19897-19906, 2022 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-35446535

RESUMEN

The functional microporous layer, acting as a mass-transfer control medium with a rational structure and surface morphology as well as high electrical conductivity, significantly affects the performance of micro-direct methanol fuel cells (µDMFCs). Bioinspired by the architecture and multi-functional properties of mangrove roots, this study develops a simple and versatile strategy based on magnetron sputtering and chemical vapor deposition to fabricate a mangrove root-inspired carbon nanotube film (MR-CNTF) as the functional interface in µDMFCs. It has features such as ultralightweight, high porosity, and good electrical conductivity. During the synthesis process, an apex-growth model of CNTF is identified. The results indicate that the MR-CNTF used as a cathodic microporous layer can remarkably facilitate the oxygen transport and water management. Because of its multi-functional structure and excellent material characteristics, the passive µDMFC displays a peak power density of 14.9 mW cm-2 at 68 mA cm-2. This value is 88.6% higher than the highest power density of the one based on a carbon nanotube array (7.9 mW cm-2) and 45% higher than that of the conventional carbon black (10.7 mW cm-2). We believe that this novel material with its multi-functional structure illuminates a promising application for fuel cells and other energy storage and conversion devices.

18.
Transl Psychiatry ; 12(1): 116, 2022 03 23.
Artículo en Inglés | MEDLINE | ID: mdl-35322015

RESUMEN

Studies of schizophrenia (SCZ) have associated auditory verbal hallucinations (AVH) with structural and functional abnormalities in frontal cortex, especially medial prefrontal cortex (mPFC). Although abnormal prefrontal network connectivity associated with language production has been studied extensively, the relationship between mPFC dysfunction (highly relevant to the pathophysiology of SCZ) and AVH has been rarely investigated. In this study, proton magnetic resonance spectroscopy was used to measure metabolite levels in the mPFC in 61 SCZ patients with persistent AVH (pAVH), 53 SCZ patients without AVH (non-AVH), and 59 healthy controls (HC). The pAVH group showed significantly lower levels of N-acetyl-aspartate + N-acetyl-aspartyl-glutamate (tNAA) and glutamate + glutamine (Glx), compared with the non-AVH (tNAA: p = 0.022, Glx: p = 0.012) and HC (tNAA: p = 0.001, Glx: p = 0.001) groups. No difference was found in the levels of tNAA and Glx between non-AVH and HC. The levels of tNAA and Glx in the mPFC was negatively correlated with the severity of pAVH (tNAA: r = -0.24, p = 0.014; Glx: r = -0.30, p = 0.002). In conclusion, pAVH in SCZ patients might be related to decreased levels of tNAA and Glx in the mPFC, indicating that tNAA or Glx might play a key role in the pathogenesis of pAVH.


Asunto(s)
Esquizofrenia , Ácido Aspártico/metabolismo , Alucinaciones/complicaciones , Humanos , Corteza Prefrontal/metabolismo , Espectroscopía de Protones por Resonancia Magnética
19.
Appl Bionics Biomech ; 2021: 8573897, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34621330

RESUMEN

A rotary cultivator is a primary cultivating machine in many countries. However, it is always challenged by high operating torque and power requirement. To address this issue, biomimetic rotary tillage blades were designed in this study for reduced torque and energy requirement based on the geometric characteristics (GC) of five fore claws of mole rats, including the contour curves of the five claw tips (GC-1) and the structural characteristics of the multiclaw combination (GC-2). Herein, the optimal blade was selected by considering three factors: (1) the ratio (r) of claw width to lateral spacing, (2) the inclined angle (θ) of the multiclaw combination, and (3) the rotary speed (n) through the soil bin tests. The results showed that the order of influence of factors on torque was n, r, and θ; the optimal combination of factors with the minimal torque was r = 1.25, θ = 60°, and n = 240 rpm. Furthermore, the torque of the optimal blade (BB-1) was studied by comparing with a conventional (CB) and a reported optimal biomimetic blade (BB-2) in the soil bin at the rotary speed from 160 to 320 rpm. Results showed that BB-1 and BB-2 averagely reduced the torque by 13.99% and 3.74% compared with CB, respectively. The field experiment results also showed the excellent soil-cutting performance of BB-1 whose average torques were largely reduced by 17.00%, 16.88%, and 21.80% compared with CB at different rotary speeds, forward velocities, and tillage depths, respectively. It was found that the geometric structure of the five claws of mole rats could not only enhance the penetrating and sliding cutting performance of the cutting edge of BB-1 but also diminish the soil failure wedge for minimizing soil shear resistance of BB-1. Therefore, the GC of five fore claws of mole rats could inspire the development of efficient tillage or digging tools for reducing soil resistance and energy consumption.

20.
Front Psychiatry ; 12: 657649, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34079482

RESUMEN

Introduction: Wernicke's encephalopathy (WE) is a severe neurological syndrome often associated with alcoholism. Clinicians tend to ignore WE in other non-alcoholic clinical settings related to malnutrition and thiamine deficiency, resulting in delayed diagnosis. The diagnosis becomes more difficult when WE is secondary to psychiatric illnesses as symptoms can be masked by the primary disease. Case Presentation: We present a case of a 56-year-old female patient with schizophrenia who was admitted to the hospital for mental and behavioral disorder, without history of alcohol. She presented symptoms of ophthalmoplegia and high muscular tension, and the brain MRI showed symmetric lesions in the bilateral basal ganglia and third ventricle. She responded well to thiamine and was discharged on hospital day 22. Conclusion: The psychiatrists should be on the alert for starvation-induced WE, especially for patients suffering from malnutrition. WE is a preventable and treatable disease, so once suspected of WE, patients ought to take adequate supplements of thiamine immediately.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...