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A suitable interlayer between the Mo back electrode and kesterite absorber layer has been proven to have a positive effect on limiting the bulk defects of the absorber by the constitute diffusion. Here, a thin Bi2S3 layer is used as the back-interface intermediate layer for the first time, this innovative approach allows for simultaneous modification of the back contact and reduction of bulk defects, resulting in improving the power conversion efficiency of the kesterite device from 9.66% to 11.8%. The evaporated Bi2O3 thin films turn into the Bi2S3 interlayers after sintering the Cu2ZnSnS4 precursor thin films. The Bi2S3 interlayer can inhibit the decomposition reaction of back contact and suppress the formation of the secondary phases. It can also optimize the Fermi level offset and promote the separation of the photoinduced carriers, resulting from its characteristic of high work function. Besides, a small part of the Bi element can diffuse into Cu2ZnSn(S, Se)4 film and induce the crystal growth and restrain Zn-related defects, which is attributed to forming the low melting-point liquid BiSex phase during the high-temperature selenization process. The conclusions highlight the bifunction of the thin Bi2S3 intermediate layer, which can provide a new approach to improve the photoelectric conversion efficiency of kesterite solar cells.
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Fly ash was used as raw material to prepare zeolites through silicate gels, assisted by the hydrothermal method. The silicate gels could be effectively formed in a few minutes in a molten alkali environment. The zeolites could be prepared by using these silicate gels through the hydrothermal method, which realizes the transformation from useless materials to highly valuable materials. The obtained zeolites were applied to the removal of ammonium in water, achieving the highvalue utilization of fly ash. The synthesized zeolites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrum (EDS), thermogravimetric (TG), and Fourier transform infrared (FTIR) spectroscopy. The study on the adsorption and removal of ammonium in water shows that the adsorption of ammonium is more in line with pseudo first-order kinetics, and the adsorption mainly occurs in the first 20 min. The adsorption can reach equilibrium in 30 min, and the maximum adsorption capacity can reach 49.1 mg/g. The adsorption capacity of ammonium has the best performance at pH = 5. Furthermore, within a certain range, an increase in temperature is beneficial for the removal of ammonium.
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OBJECTIVE: This study aims to evaluate the clinical efficacy and short-term prognosis of using flexible cystoscopy with percutaneous nephrolithotomy to treat complex renal stones. METHODS: A retrospective analysis was conducted on patients with complex kidney stones treated at Gansu Provincial Hospital of TCM and Lanzhou City No. 2 People's Hospital from July 2019 to July 2022. The study divided the patients into a control group (n=95), who underwent percutaneous nephrolithotomy alone, and an observation group (n=109), who received additional holmium laser lithotripsy and cystoscopy. We compared stone clearance rates at 5 days and 1 month post-surgery, analyzed patient prognosis over a year based on stone recurrence, and assessed risk factors through logistic regression. Perioperative data, changes in renal function indiex 3 days post-surgery, and complication rates were also evaluated. RESULTS: The observation group exhibited a significantly higher stone clearance rate at 5 days post-surgery (P=0.002) compared to the control group, although no significant difference was observed at 1 month (P=0.823). The operative time was significantly shorter (P<0.001), and postoperative levels of BUA, Cys-c, and ß2-BMG were lower (P<0.05) in the observation group. Additionally, treatment regimen, BMI, and STONE score were influencing factors for stone recurrence within 1 year. CONCLUSION: Flexible cystoscopy combined with percutaneous nephrolithotomy offers superior short-term outcomes in the treatment of complex renal stones, including enhanced stone clearance, reduced operative time, and minimized renal function impairment shortly after surgery. Moreover, treatment approach, BMI, and STONE score play pivotal roles in predicting stone recurrence.
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Morphology of the absorber plays a decisive role in photoelectric conversion efficiency (PCE) of kersterite solar cells. Cu2ZnSn(S,Se)4 (CZTSSe) grain prepared from dimethyl sulfoxide (DMSO)-based solution easily grows into large grains, which can lead to the formation of some holes at the back of the absorber. These holes cause the recombination of photocarriers and greatly weaken the performance of CZTSSe devices. Here, trace amounts of thioglycolic acid (TGA) are introduced to the DMSO-based solution, and a combination of TGA and metal is formed in the absorber, leading to the formation of fine grains in the CZTSSe absorber. Next, post-annealing (PA) in a N2 atmosphere is performed to promote Na diffusion, helping the transition from a fine-grain layer to a low-resistivity carbon layer at the interface between CZTSSe and Mo and avoiding the drawbacks of the DMSO-based system. Finally, the champion PCE of the CZTSSe device can be improved to 10.05% from 8.06%. The conclusions demonstrate that the construction of a carbon layer can boost the performance of CZTSSe devices.
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As a high efficiency method for chloride removal, Friedel's salt precipitation (FSP) method has attracted much attention in zero liquid discharge (ZLD) of flue gas desulfurization (FGD) wastewater. This review provides comprehensive knowledge of FSP method for chloride removal through analysis of the evolution, reaction mechanisms and influential factors, and describes the recent research progress. FSP method is a cost-efficient technology to remove chloride from saline wastewater by adding lime and aluminate. Chloride ions react with the precipitants by adsorption or/and ion exchange to form Friedel's salt, which is affected by the reaction conditions including reaction time, temperature, interferential ions, etc. The effluent of this process can be reused as the makeup water of desulfurization tower, and the dechloridation precipitates can be reclaimed as adsorption materials and sludge conditioners. That can not only offset a fraction of the treatment cost, but also avoid secondary pollution, so ZLD of FGD wastewater can be achieved. This paper summarizes the deficiencies and potential improvement measures of FSP method. We believe this technology is a promising way to achieve ZLD of FGD wastewater and other wastewater containing chloride, and expect FSP method would become more mature and be widely applied in hypersaline wastewater treatment in the foreseeable future.
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Cloruros , Aguas Residuales , Cloruro de Calcio , Óxido de AluminioRESUMEN
Lithium-ion battery based on LiCrTiO4 (LCTO) is considered to be a promising anode material, as they provide higher safety and durability beyond than that of graphite electrode. However, the applications of this transformative technology demand improved inherent electrical conductivity of LCTO as well as a simple and rapid synthetic route. Here, LCTO with oxygen vacancies (OVs) is fabricated using high-pressure synthesis technology in only 40 min. The optimal synthesis pressure is 0.8 GPa (LCTO-0.8). The reversible capacity of LCTO-0.8 at 1C is 131 mA h g-1 after 1000 cycles and the capacity retention is nearly 97%, and the reversible capacity of LCTO synthesized at atmospheric pressure (LCTO-P) is 85 mA h g-1 under the same circumstances. Even at 5C, the reversible capacity is 110 mA h g-1 , which is 77% higher than LCTO-P. Furthermore, it is confirmed by theoretical calculations that the introduction of OVs has the occupation of electronic states at the Fermi level, which greatly enhances the intrinsic conductivity of LCTO. Specifically, the electronic conductivity has increased by two orders of magnitude compared with LCTO-P. Therefore, high-pressure synthesis technology endows LCTO with superior characteristics, providing a new avenue for industrialization.
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Obsessive-compulsive disorder (OCD) is a debilitating and disabling neuropsychiatric disorder, whose neurobiological basis remains unclear. Although traditional static resting-state magnetic resonance imaging (rfMRI) studies have found aberrant functional connectivity (FC) in OCD, alterations in whole-brain FC and topological properties in the context of brain dynamics remain relatively unexplored. The rfMRI data of 29 patients with OCD and 40 healthy controls were analyzed using group independent component analysis to obtain independent components (ICs) and a sliding-window approach to generate dynamic functional connectivity (dFC) matrices. dFC patterns were clustered into three reoccurring states, and state transition metrics were obtained. Then, graph-theory methods were applied to dFC matrices to calculate the variability of network topological organization. The occurrence of a state (State 1) with the highest modularity index and lowest mean FC between networks was increased significantly in OCD, and the fractional time in brain State 1 was positively correlated with anxiety level in patients. State 1 was characterized by having positive connections within default mode (DMN) and salience networks (SAN), and negative coupling between the two networks. Additionally, ICs belonging to DMN and SAN showed lower temporal variability of nodal degree centrality and efficiency in patients, which was related to longer illness duration and higher current obsession ratings. Our results provide evidence of clinically relevant aberrant dynamic brain activity in OCD. Increased functional segregation among networks and impaired functional flexibility in connections among brain regions in DMN and SAN may play important roles in the neuropathology of OCD.
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Algoritmos , Encéfalo/fisiopatología , Conectoma , Red Nerviosa/fisiopatología , Trastorno Obsesivo Compulsivo/fisiopatología , Adolescente , Adulto , Encéfalo/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Red Nerviosa/diagnóstico por imagen , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Adulto JovenRESUMEN
We describe the complete mitochondrial genome of the endangered fish Sinocyclocheilus aluensis. It is a circular molecule of 16,583 bp in size with a D-loop region and contains 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes and 13 protein-coding genes, and all genes show the typical gene arrangement conforming to the vertebrate consensus. The overall base composition of S. aluensis mitogenome is 31.1% for A, 26.9% for C, 16.6% for G, and 25.4% for T. The percentage of G + C content is 43.5%. Phylogenetic analysis demonstrated that all Sinocyclocheilus species clustered together and formed a monophyletic group. The mitochondrial genome sequencing for S. aluensis in this study provides important molecular data for further evolutionary research for Sinocyclocheilus.
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Obsessive-compulsive disorder (OCD) is a disabling neuropsychiatric disorder whose neurobiological basis remains unclear. Magnetic resonance imaging (MRI) studies have reported functional and structural alterations of the anterior cingulate cortex (ACC) in OCD. In this study, we explored the functional activity of subregions of the ACC and effective connectivity (EC) between ACC subregions and the whole brain in OCD. We used a Granger causality analysis (GCA) to identify the direction of information flow and whether the impact of that flow was excitatory or inhibitory. We performed resting-state functional MRI in 31 patients with OCD and 36 healthy controls and analyzed the amplitude of low-frequency fluctuation (ALFF) and coefficient-based GCA. The left pregenual ACC (pACC) in patients with OCD showed decreased ALFF relative to controls. There was significantly decreased excitatory output from the left pACC to both right dorsal superior frontal gyrus (dSFG) and left precuneus in patients compared with controls. Patients also had decreased inhibitory input to left pACC from left ventral SFG and left thalamus and caudate relative to controls. Results were similar in drug-naive patients and those with prior but not current psychopharmacological treatment. In patients, path coefficients of GCA from left pACC to right dSFG showed significant negative correlations with obsession and anxiety ratings. Decreased spontaneous neural activity and altered EC of pACC with widely distributed cortical circuitry, and associations with clinical ratings highlight the importance of pACC functional alteration in OCD.
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Potenciales Postsinápticos Excitadores/fisiología , Giro del Cíngulo/diagnóstico por imagen , Potenciales Postsinápticos Inhibidores/fisiología , Red Nerviosa/diagnóstico por imagen , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Adolescente , Adulto , Femenino , Giro del Cíngulo/fisiopatología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Red Nerviosa/fisiopatología , Trastorno Obsesivo Compulsivo/fisiopatología , Adulto JovenRESUMEN
AIM: Psychotic-like experiences (PLEs) are common in adolescents who have experienced or are experiencing trauma. However, the potential relationships between exposure to a major earthquake, negative life events or maltreatment and PLEs in Chinese adolescents are poorly understood. Therefore, this study explored the prevalence of PLEs and the psychosocial correlates in adolescent earthquake survivors. METHODS: A total of 6132 adolescents from 11 primary and high schools in the areas most severely affected by the Ya'an earthquake completed questionnaires on earthquake exposure, maltreatment, negative life events and PLEs, which included paranoid ideation and psychoticism. RESULTS: It was found that earthquake exposure significantly contributed to the PLEs, child maltreatment explained a significant amount of the PLE variances, emotional abuse had the most important PLE role and negative life events also explained a large amount of the PLE variances, of which interpersonal difficulties and academic pressure had the greatest effects. CONCLUSIONS: Interventions should seek to reduce parental emotional abuse, reduce academic performance pressure, improve interpersonal skills and resolve interpersonal difficulties, and specific interventions should target children and adolescents exposed to the earthquake to prevent PLEs, schizophrenia or other mental illnesses arising from multiple traumas.
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Terremotos , Trastornos Mentales , Trastornos Psicóticos , Adolescente , Niño , China/epidemiología , Humanos , Trastornos Psicóticos/epidemiología , Encuestas y CuestionariosRESUMEN
The dorsolateral prefrontal cortex (DLPFC), a key structure in the executive system, has consistently emerged as a crucial element in the pathophysiology of obsessive-compulsive disorder (OCD). However, the neural primacy of the DLPFC remains elusive in this disorder. We investigated the causal interaction (measured by effective connectivity) between the DLPFC and the remaining brain areas using bivariate Granger causality analysis of resting-state fMRI collected from 88 medication-free OCD patients and 88 matched healthy controls. Additionally, we conducted seed-based functional connectivity (FC) analyses to identify network-level neural functional alterations using the bilateral DLPFC as seeds. OCD patients demonstrated reduced FC between the right DLPFC and right orbitofrontal cortex (OFC), and activity in the right OFC had an inhibitory effect on the right DLPFC. Additionally, we observed alterations in both feedforward and reciprocal influences between the inferior temporal gyrus (ITG) and the DLPFC in patients. Furthermore, activity in the cerebellum had an excitatory influence on the right DLPFC in OCD patients. These findings may help to elucidate the psychopathology of OCD by detailing the directional connectivity between the DLPFC and the rest of the brain, ultimately helping to identify regions that could serve as treatment targets in OCD.
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Trastorno Obsesivo Compulsivo , Encéfalo , Mapeo Encefálico , Humanos , Imagen por Resonancia Magnética , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Corteza Prefrontal/diagnóstico por imagenRESUMEN
BACKGROUND: The aim of this longitudinal study was to identify risk factors for posttraumatic stress disorder (PTSD) in inpatients injured in the Ludian earthquake and examine the relationship between PTSD symptoms and health-related quality of life (HRQoL) following the earthquake. METHODS: Three assessments were performed during an 18-month follow-up period. In total, one-hundred forty-seven inpatients of one-hundred seventy-four inpatients (85% of the initial sample) underwent all the assessments. Injured inpatients admitted to the No. 1 People's Hospital of Zhaotong City after a severe earthquake (6.5 on the Richter scale) were enrolled in the study and assessed using the Posttraumatic Stress Disorder Checklist-Civilian Version, Clinician-Administered Posttraumatic Stress Disorder Scale, and Medical Outcomes Study Short Form-36 Scale. RESULTS: At the first, third and eighteenth months after the earthquake, the prevalence rates for PTSD were 23, 14, and 7%, respectively. In a regression model, bereavement, history of major diseases, and severe injury in the earthquake were associated with severe PTSD symptoms. HRQoL was negatively correlated with PTSD symptoms. Compared to that of Chinese norms, participants' HRQoL was significantly lower in all eight HRQoL domains of the Medical Outcomes Study Short Form-36 Scale. CONCLUSIONS: The findings suggest that a substantial proportion of inpatients injured in the earthquake experienced severe PTSD symptoms and poor HRQoL. Therefore, early preventive programs and interventions should be implemented following disasters, to reduce PTSD and improve HRQoL in injured individuals.
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Pueblo Asiatico/psicología , Terremotos/estadística & datos numéricos , Pacientes Internos/psicología , Calidad de Vida/psicología , Trastornos por Estrés Postraumático/psicología , Sobrevivientes/psicología , Adulto , Pueblo Asiatico/estadística & datos numéricos , China , Desastres/estadística & datos numéricos , Femenino , Humanos , Pacientes Internos/estadística & datos numéricos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Sobrevivientes/estadística & datos numéricosRESUMEN
Background: The amygdala has been implicated in obsessive-compulsive disorder (OCD), a common, disabling illness. However, the regional distribution of anatomic alterations in this structure and their association with the symptoms of OCD remains to be established. Methods: We collected high-resolution 3D T1-weighted images from 81 untreated patients with OCD and no lifetime history of comorbid psychotic, affective or anxiety disorders, and from 95 age- and sex-matched healthy controls. We extracted the volume of the central nucleus of the amygdala (CeA) and the basolateral complex of the amygdala (BLA) and compared them across groups using FreeSurfer 6.0. In exploratory analyses, we evaluated other subnuclei, including the cortical medial nuclei, the anterior amygdaloid area, and the corticoamygdaloid transition area. Results: Patients with OCD had reduced amygdala volume bilaterally compared with healthy controls (left, p = 0.034; right, p = 0.002). Volume reductions were greater in the CeA (left: -11.9%, p = 0.002; right: -13.3%, p < 0.001) than in the BLA (left lateral nucleus: -3.3%, p = 0.029; right lateral nucleus: -3.9%, p = 0.018; right basal nucleus: -4.1%, p = 0.017; left accessory basal nucleus: -6.5%, p = 0.001; right accessory basal nucleus: -9.3%, p < 0.001). Volume reductions in the CeA were associated with illness duration. Exploratory analysis revealed smaller medial (left: -15.4%, p < 0.001, η2 = 0.101) and cortical (left: -9.1%, p = 0.001, η2 = 0.058; right: -15.4%, p < 0.001, η2 = 0.175) nuclei in patients with OCD compared with healthy controls. Limitations: Although the strict exclusion criteria used in the study helped us to identify OCD-specific alterations, they may have limited generalizability to the broader OCD population. Conclusion: Our results provide a comprehensive anatomic profile of alterations in the amygdala subnuclei in untreated patients with OCD and highlight a distinctive pattern of volume reductions across subnuclei in OCD. Based on the functional properties of the amygdala subnuclei established from preclinical research, CeA impairment may contribute to behavioural inflexibility, and BLA disruption may be responsible for altered fear conditioning and the affective components of OCD.
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Complejo Nuclear Basolateral/patología , Núcleo Amigdalino Central/patología , Trastorno Obsesivo Compulsivo/patología , Adulto , Complejo Nuclear Basolateral/diagnóstico por imagen , Núcleo Amigdalino Central/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Adulto JovenRESUMEN
BACKGROUND: Subcortical nuclei are important components in the pathology model of obsessive-compulsive disorder (OCD), and subregions of these structures subserve different functions that may distinctively contribute to OCD symptoms. Exploration of the subregional-level profile of structural abnormalities of these nuclei is needed to develop a better understanding of the neural mechanism of OCD. METHODS: A total of 83 medication-free, non-comorbid OCD patients and 93 age- and sex-matched healthy controls were recruited, and high-resolution T1-weighted MR images were obtained for all participants. The volume and shape of the subcortical nuclei (including the nucleus accumbens, amygdala, caudate, pallidum, putamen and thalamus) were quantified and compared with an automated parcellation approach and vertex-wise shape analysis using FSL-FIRST software. Sex differences in these measurements were also explored with an exploratory subgroup analysis. RESULTS: Volumetric analysis showed no significant differences between patients and healthy control subjects. Relative to healthy control subjects, the OCD patients showed an expansion of the lateral amygdala (right hemisphere) and right pallidum. These deformities were associated with illness duration and symptom severity of OCD. Exploratory subgroup analysis by sex revealed amygdala deformity in male patients and caudate deformity in female patients. CONCLUSIONS: The lateral amygdala and the dorsal pallidum were associated with OCD. Neuroanatomic evidence of sexual dimorphism was also found in OCD. Our study not only provides deeper insight into how these structures contribute to OCD symptoms by revealing these subregional-level deformities but also suggests that gender effects may be important in OCD studies.
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Encéfalo/diagnóstico por imagen , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Adulto , Amígdala del Cerebelo/diagnóstico por imagen , Núcleo Caudado/diagnóstico por imagen , Femenino , Lateralidad Funcional , Globo Pálido/diagnóstico por imagen , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Núcleo Accumbens/diagnóstico por imagen , Trastorno Obsesivo Compulsivo/psicología , Escalas de Valoración Psiquiátrica , Putamen/diagnóstico por imagen , Caracteres Sexuales , Tálamo/diagnóstico por imagen , Adulto JovenRESUMEN
BACKGROUND: Previous resting-state functional magnetic resonance imaging (rs-fMRI) studies have revealed intrinsic regional activity alterations in obsessive-compulsive disorder (OCD), but those results were based on group analyses, which limits their applicability to clinical diagnosis and treatment at the level of the individual. METHODS: We examined fractional amplitude low-frequency fluctuation (fALFF) and applied support vector machine (SVM) to discriminate OCD patients from healthy controls on the basis of rs-fMRI data. Values of fALFF, calculated from 68 drug-naive OCD patients and 68 demographically matched healthy controls, served as input features for the classification procedure. RESULTS: The classifier achieved 72% accuracy (p ≤ 0.001). This discrimination was based on regions that included the left superior temporal gyrus, the right middle temporal gyrus, the left supramarginal gyrus and the superior parietal lobule. CONCLUSIONS: These results indicate that OCD-related abnormalities in temporal and parietal lobe activation have predictive power for group membership; furthermore, the findings suggest that machine learning techniques can be used to aid in the identification of individuals with OCD in clinical diagnosis.
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Imagen por Resonancia Magnética/estadística & datos numéricos , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Máquina de Vectores de Soporte/estadística & datos numéricos , Adulto , Encéfalo/fisiopatología , Mapeo Encefálico/métodos , Estudios de Casos y Controles , Femenino , Humanos , Sistema Límbico/diagnóstico por imagen , Sistema Límbico/fisiopatología , Imagen por Resonancia Magnética/métodos , Masculino , Análisis Multivariante , Trastorno Obsesivo Compulsivo/patología , Lóbulo Parietal/diagnóstico por imagen , Lóbulo Parietal/fisiopatología , Descanso/psicología , Lóbulo Temporal/diagnóstico por imagen , Lóbulo Temporal/fisiopatología , Adulto JovenRESUMEN
In this study, we sought to identify alterations of hippocampal shape and subfield volumes in a relatively large sample of medication-free obsessive-compulsive disorder (OCD) patients without comorbid depression. 3D T1-weighted Magnetic Resonance Imaging scans were collected from 81 medication-free OCD patients and 95 age- and sex-matched healthy controls (HC). Total hippocampal volume and volume of eight bilateral subfields were measured using FreeSurfer software. Subregional shape deformity was examined via FSL software. Volumetric and shape differences between groups and correlations with OCD symptoms were examined. The volume of right hippocampus was significantly reduced in OCD patients (p = .001, η2 = 0.065). Follow-up analysis of right hemisphere subfields showed reduced volume in right subiculum (p < .001, η2 = 0.081), presubiculum (p < .001, η2 = 0.125), CA2/3 (p = .001, η2 = 0.06), and hippocampal tail (p < 0.001, η2 = 0.105), while the volume of right fimbria was increased (p = .001, η2 = 0.058). Shape analysis revealed a bilateral outward bending in the hippocampal body related to a lateral displacement of hippocampus from the body to the tail. Symptom severity was correlated with volumes of presubiculum (with compulsions, r = -0.25, p = .024) and fimbria (with obsessions, r = -0.28, p = .012), and with the lateral shift of middle and posterior hippocampus (with obsessions). Alterations across hippocampal subfields and overall shape may contribute to the distinctive cognitive and affective abnormalities associated with OCD.
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Hipocampo/patología , Trastorno Obsesivo Compulsivo/patología , Adulto , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Imagen por Resonancia Magnética , Masculino , Estudios ProspectivosRESUMEN
Recent developments in psychoradiological researches have highlighted the disrupted organization of large-scale functional brain networks in obsessive-compulsive disorder (OCD). However, whether abnormal activation of localized brain areas would affect network dysfunction remains to be fully characterized. We applied both univariate analysis and multivariate pattern analysis (MVPA) approaches to investigate the abnormalities of regional homogeneity (ReHo), an index to measure the localized connectivity, in 88 medication-free patients with OCD and 88 healthy control subjects (HCS). Resting-state functional magnetic resonance imaging (RS-fMRI) data of all the participants were acquired in a 3.0-T scanner. First, we adopted a traditional univariate analysis to explore ReHo alterations between the patient group and the control group. Subsequently, we utilized a support vector machine (SVM) to examine whether ReHo could be further used to differentiate patients with OCD from HCS at the individual level. Relative to HCS, OCD patients showed lower ReHo in the bilateral cerebellum and higher ReHo in the bilateral superior frontal gyri (SFG), right inferior parietal gyrus (IPG), and precuneus [P < 0.05, family-wise error (FWE) correction]. ReHo value in the left SFG positively correlated with Yale-Brown Obsessive Compulsive Scale (Y-BOCS) total score (r = 0 0.241, P = 0.024) and obsessive subscale (r = 0.224, P = 0.036). The SVM classification regarding ReHo yielded an accuracy of 78.98% (sensitivity = 78.41%, specificity = 79.55%) with P < 0.001 after permutation testing. The most discriminative regions contributing to the SVM classification were mainly located in the frontal, temporal, and parietal regions as well as in the cerebellum while the right orbital frontal cortex was identified with the highest discriminative power. Our findings not only suggested that the localized activation disequilibrium between the prefrontal cortex (PFC) and the cerebellum appeared to be associated with the pathophysiology of OCD but also indicated the translational role of the localized connectivity as a potential discriminative pattern to detect OCD at the individual level.
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BACKGROUND: Using the resting-state functional magnetic resonance imaging (rs-fMRI) in a relatively large sample of drug-naive patients with obsessive-compulsive disorder (OCD), the current study aims to explore alterations in regional and network-level neural function and to determine the association between these alterations in intrinsic neural activity and symptom severity in OCD. METHODS: A total of 68 drug-naive OCD patients and 68 healthy control subjects (HCS) were examined using rs-fMRI. Regional cerebral function was evaluated by measuring the fraction of amplitude of low-frequency fluctuation (fALFF). Regions with fALFF alterations were used as seeds in whole-brain functional connectivity (FC) analysis. Statistical analyses of fALFF and FC differences between OCD patients with HCS were performed voxel-by-voxel using a two-sample t-test in Statistical Parametric Mapping version 8 (SPM8). Whole brain correlation analyses were performed to identify the association between functional neural correlates and OCD symptom severity evaluated using Yale-Brown Obsessive Compulsive scale (Y-BOCS) and subscale scores. RESULTS: Relative to HCS, OCD patients showed higher fALFF in the right putamen and right superior frontal gyrus (Pâ¯<â¯0.05, corrected for AlphaSim); higher FC in the limbic-striatal circuit and lower FC in the fronto-temporal and fronto-striato-thalamic networks (Pâ¯<â¯0.05, corrected for AlphaSim). FC in striato-thalamic junction was negatively correlated with the Y-BOCS total score (râ¯=â¯-0.493, Pâ¯<â¯0.001). CONCLUSION: These findings of focal spontaneous hyperfunction confirmed the prevailing frontal-striatal model of OCD, and altered brain connectivity in large-scale resting-state networks indicated a connectivity-based pathophysiological process in OCD.
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Encéfalo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Adulto , Mapeo Encefálico , Cuerpo Estriado/diagnóstico por imagen , Femenino , Lóbulo Frontal/diagnóstico por imagen , Humanos , Sistema Límbico/diagnóstico por imagen , Masculino , Vías Nerviosas/diagnóstico por imagen , Trastorno Obsesivo Compulsivo/psicología , Escalas de Valoración Psiquiátrica , Tálamo/diagnóstico por imagen , Adulto JovenRESUMEN
Previous resting-state functional magnetic resonance imaging (rs-fMRI) studies of obsessive-compulsive disorder (OCD) have facilitated our understanding of OCD pathophysiology based on its intrinsic activity. However, whether the group difference derived from univariate analysis could be useful for informing the diagnosis of individual OCD patients remains unclear. We aimed to apply multivariate pattern analysis of different rs-fMRI parameters to distinguish drug-naive patients with OCD from healthy control subjects (HCS). Fifty-four drug-naive OCD patients and 54 well-matched HCS were recruited. Four different rs-fMRI parameter maps, including the amplitude of low-frequency fluctuations (ALFF), fractional amplitude of low-frequency fluctuations (fALFF), regional homogeneity (ReHo) and functional connectivity strength (FCS), were calculated. Training of a support vector machine (SVM) classifier using rs-fMRI maps produced voxelwise discrimination maps. Overall, the classification accuracies were acceptable for the four rs-fMRI parameters. Excellent performance was achieved when ALFF maps were employed (accuracy, 95.37%, p < 0.01), good performance was achieved by using ReHo maps, weaker performance was achieved by using fALFF maps, and fair performance was achieved by using FCS maps. The brain regions showing the greatest discriminative power included the prefrontal cortex, anterior cingulate cortex, precentral gyrus, and occipital lobes. The application of SVM to rs-fMRI features may provide potential power for OCD classification.
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Mapeo Encefálico , Encéfalo/fisiopatología , Imagen por Resonancia Magnética , Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Adolescente , Adulto , Área Bajo la Curva , Encéfalo/diagnóstico por imagen , Estudios de Casos y Controles , China , Femenino , Humanos , Masculino , Análisis Multivariante , Trastorno Obsesivo Compulsivo/fisiopatología , Descanso , Estudios Retrospectivos , Máquina de Vectores de Soporte , Adulto JovenRESUMEN
OBJECTIVE: Health care workers performing rescue tasks in large-scale disaster areas are usually challenged in terms of physical and mental endurance, which can affect their lifestyles. Nevertheless, data on whether health care workers tend to adopt healthy lifestyles after disasters are limited. This paper compares the adoption of healthy lifestyle behaviors among health care workers with that among non-health care workers in a postdisaster area. METHODS: This cross-sectional observational study was conducted in August 2016. The Health-Promoting Lifestyle Profile II questionnaire was used to interview 261 health care workers and 848 non-health care workers. RESULTS: Results of the multivariable linear models showed that health care workers had lower physical activity levels (ß=-1.363, P<.0001), worse stress management (ß=-1.282, P<.0001), slower spiritual growth (ß=-1.228, P=.002), and poorer interpersonal relationships (ß=-0.814, P=.019) than non-health care workers. However, no significant differences were found in either nutrition (ß=-0.362, P=.319) or health responsibility (ß=-0.421, P=.283). CONCLUSIONS: Health care workers had less healthy lifestyle behaviors, including physical activity, stress management, spiritual growth, and interpersonal relationships. Further studies are needed to develop health-improving interventions for health care workers in postdisaster areas. (Disaster Med Public Health Preparedness. 2019;13:230-235).