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Network neuroscience offers a unique framework to understand the organizational principles of the human brain. Despite recent progress, our understanding of how the brain is modulated by focal lesions remains incomplete. Resection of the temporal lobe is the most effective treatment to control seizures in pharmaco-resistant temporal lobe epilepsy (TLE), making this syndrome a powerful model to study lesional effects on network organization in young and middle-aged adults. Here, we assessed the downstream consequences of a focal lesion and its surgical resection on the brain's structural connectome, and explored how this reorganization relates to clinical variables at the individual patient level. We included adults with pharmaco-resistant TLE (n = 37) who underwent anterior temporal lobectomy between two imaging time points, as well as age- and sex-matched healthy controls who underwent comparable imaging (n = 31). Core to our analysis was the projection of high-dimensional structural connectome data-derived from diffusion MRI tractography from each subject-into lower-dimensional gradients. We then compared connectome gradients in patients relative to controls before surgery, tracked surgically-induced connectome reconfiguration from pre- to postoperative time points, and examined associations to patient-specific clinical and imaging phenotypes. Before surgery, individuals with TLE presented with marked connectome changes in bilateral temporo-parietal regions, reflecting an increased segregation of the ipsilateral anterior temporal lobe from the rest of the brain. Surgery-induced connectome reorganization was localized to this temporo-parietal subnetwork, but primarily involved postoperative integration of contralateral regions with the rest of the brain. Using a partial least-squares analysis, we uncovered a latent clinical imaging signature underlying this pre- to postoperative connectome reorganization, showing that patients who displayed postoperative integration in bilateral fronto-occipital cortices also had greater preoperative ipsilateral hippocampal atrophy, lower seizure frequency and secondarily generalized seizures. Our results bridge the effects of focal brain lesions and their surgical resections with large-scale network reorganization and interindividual clinical variability, thus offering new avenues to examine the fundamental malleability of the human brain.
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Lobectomía Temporal Anterior , Conectoma , Epilepsia del Lóbulo Temporal , Lóbulo Temporal , Humanos , Femenino , Masculino , Adulto , Epilepsia del Lóbulo Temporal/cirugía , Epilepsia del Lóbulo Temporal/fisiopatología , Epilepsia del Lóbulo Temporal/diagnóstico por imagen , Epilepsia del Lóbulo Temporal/patología , Lóbulo Temporal/patología , Lóbulo Temporal/cirugía , Lóbulo Temporal/diagnóstico por imagen , Lobectomía Temporal Anterior/métodos , Persona de Mediana Edad , Adulto Joven , Imagen de Difusión Tensora , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/patología , Epilepsia Refractaria/cirugía , Epilepsia Refractaria/diagnóstico por imagen , Epilepsia Refractaria/fisiopatología , Epilepsia Refractaria/patologíaRESUMEN
AIMS: Mapping progressive patterns of structural damage in epilepsies with idiopathic and secondarily generalized tonic-clonic seizures with causal structural covariance networks and multiple analysis strategies. METHODS: Patients with idiopathic generalized tonic-clonic seizures (IGTCS) (n = 114) and secondarily generalized tonic-clonic seizures (SGTCS) (n = 125) were recruited. Morphometric parameter of gray matter volume was analyzed on structural MRI. Structural covariance network based on granger causality analysis (CaSCN) was performed on the cross-sectional morphometric data sorted by disease durations of patients. Seed-based CaSCN analysis was firstly carried out to map the progressive and influential patterns of damage to thalamus-related structures. A novel technique for voxel-based CaSCN density (CaSCNd) analysis was further proposed, enabling for identifying the epicenter of structural brain damage during the disease process. RESULTS: The thalamus-associated CaSCNs demonstrated different patterns of progressive damage in two types of generalized tonic-clonic seizures. In IGTCS, the structural damage was predominantly driven from the thalamus, and expanded to the cortex, while in SGTCS, the damage was predominantly driven from the cortex, and expanded to the thalamus through the basal ganglia. CaSCNd analysis revealed that the IGTCS had an out-effect epicenter in the thalamus, whereas the SGTCS had equipotent in- and out-effects in the thalamus, cortex, and basal ganglia. CONCLUSION: CaSCN revealed distinct damage patterns in the two types of GTCS, featuring with measurement of structural brain damage from the accumulating effect over a relatively long time period. Our work provided evidence for understanding network impairment mechanism underlying different GTCSs.
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Epilepsia Generalizada , Epilepsia Tónico-Clónica , Epilepsia , Humanos , Estudios Transversales , Convulsiones , Corteza Cerebral , Sustancia Gris , Imagen por Resonancia Magnética/métodos , Epilepsia Generalizada/diagnóstico por imagenRESUMEN
Films with high barrier, flame-retardant, and antibacterial properties are beneficial in terms of food and logistics safety. Herein, a polyelectrolyte complex (PEC) of N-(2-hydroxyl)-propyl-3-trimethylammonium chitosan chloride (HTCC, chitosan derivative) and phytic acid (PA) was successfully prepared and then incorporated into a polyvinyl alcohol (PVA) matrix to fabricate a composite film with satisfactory barrier, fire-retardant, and antibacterial properties. The influence of HTCC/PA (HTPA) on the structural, physical and functional properties of the PVA matrix was investigated. Compared with the PVA film, PVA-HTPA6 film exhibited 3.38 times of flexibility and 83.33 % and 80.64 % of water vapor permeability and oxygen permeability, respectively. Benefiting from HTPA, the PVA-HTPA6 film exhibited outstanding flame-retardant capacity, with a high LOI value (33.30 %) and immediate self-extinguishing behaviour. Furthermore, the HTPA endowed the films with excellent antibacterial properties. Compared with other films, the PVA-HTPA6 film effectively maintained the quality of pork during storage at 4 °C for 9 days. Our findings indicate that the films are promising for packaging and logistics safety with oil-containing foods.
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Quitosano , Retardadores de Llama , Quitosano/farmacología , Quitosano/química , Alcohol Polivinílico/química , Ácido Fítico , Polielectrolitos , Antibacterianos/farmacología , Antibacterianos/química , Embalaje de AlimentosRESUMEN
Pr3+-related intervalence charge transfer (IVCT) bands are a research hotspot owing to their amelioration in the luminescence thermal quenching of Pr3+-activated phosphors. Here, a typical IVCT band displacement strategy via a topological chemical scheme is reported to optimize the luminescence thermal quenching performance of praseodymium-doped niobo-tantalate. The substitution of Ta5+ ions for Nb5+ ions reduces the valence-weighted average cation optical electronegativity and increases the bond lengths of the activator (Pr3+) to the ligand cations (Nb5+ and Ta5+) via adjusting the crystal structure, leading to an increase in the IVCT energy level position from 3.521 to 4.139 eV. The increase in the IVCT energy level leads to an increase in the number of electrons located in the Pr3+ 3P0 energy level, which compensates for the emission of 1D2 during warming. Especially, the energy gap value of the IVCT band is positively correlated with the thermal quenching activation energy ΔE2. ΔE2 increases, the crossover point rises, and the nonradiative transition decreases, further enhancing the Pr3+ 1D2 emission. At 503 K, the 1D2 emission integral intensity increases from 14 to 224% relative to the 303 K original integral intensity. This IVCT band displacement strategy can be used as a scheme for designing antithermal quenching luminescence materials.
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Intelligent labels provide customers with food freshness information. However, the existing label response is limited and can only detect a single kind of food. Here, an intelligent cellulose-based label with highly antibacterial activity for a multi-range sensing freshness was developed to overcome the limitation. Cellulose fibers were modified using oxalic acid to graft -COO- followed by binding chitosan quaternary ammonium salt (CQAS), the remaining charges of which attached methylene red and bromothymol blue to form response fibers and to further self-assemble into the intelligent label. CQAS electrostatically gathered the dispersed fibers, resulting in an increase in TS and EB of 282 % and 16.2 %, respectively. After that, the rest positive charges fixed the anionic dyes to broaden pH response range of 3-9 effectively. More significantly, the intelligent label exhibited highly antimicrobial activity, killing 100 % of staphylococcus aureus. The rapid acid-base response revealed the potential for practical application in which the label color from green to orange represented the milk or spinach from fresh to close to spoiled, and from green to yellow, and to light green indicated the pork fresh, acceptable, and close to spoiled. This study paves a way for the preparation of intelligent labels in large-scale and promote the commercial application to improve food safety.
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Celulosa , Quitosano , Celulosa/química , Alimentos Marinos/análisis , Azul de Bromotimol , Calidad de los Alimentos , Colorantes , Quitosano/química , Embalaje de Alimentos/métodos , Concentración de Iones de Hidrógeno , Antocianinas/químicaRESUMEN
Thermal quenching has always been one of the most difficult issues in creating high-quality phosphor conversion light-emitting diodes (pc-LED), and a family of strategies are urgently needed to improve the luminescence performance of phosphors at high temperatures. In this contribution, a novel B'-site substitution CaLaMgSbxTa1-xO6:Bi3+ phosphor was constructed using an ion substitution strategy in the matrix with a green activator Bi3+ and a novel double perovskite material. When Sb5+ replaces Ta5+, a surprising increase in luminescence intensity occurs and the thermal quenching properties are greatly improved. The shift of the Raman characteristic peak to a smaller wavenumber and the reduction of the Bi-O bond length confirm that the crystal field environment around Bi3+ changes, which has a substantial effect on the crystal field splitting and nepheline effect of Bi3+ ions, affecting the crystal field splitting energy (Dq). This results in a corresponding increase of the band gap and the thermal quenching activation energy (ΔE) of the activator Bi3+. From the perspective of Dq, the intrinsic relationships among the activator ion band gap, bond length, and Raman characteristic peak changes were analyzed, and a mechanism for regulating luminescence thermal quenching properties was constructed, which provides an effective strategy for improving the promising new materials such as double perovskite.
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A cellulose-based matrix for monitoring milk freshness (MF) was produced from rice straw particles (RSPs) in a 0.125-0.150 mm that was bis-quaternized to attach bromocresol purple (BP) as a sensor. Under alkali conditions, the obstinate structure of the rice straw had opened, thereby improving the accessibility of the cellulose. Bis-quaternization created more adsorption sites for BP. The maximum adsorption capacity was 97.68 mg/g. The sensors were interwoven with cellulosic fibers to form the cellulose-based label with a relatively loose three-dimensional structure via hydrogen bonds. As the proportion of BP-BCRPs was increased from 10% to 40%, the air permeability of the label increased from 3.76 to 15.01 mm/s, which increased the response to the tested gases (10.12 s for 1 mL of acetic acid). The intelligent label exhibited excellent sensitivity at pH values of 3-9 with highly saturated color changes. During the storage period, the label color shifted from blue-purple to yellow as acidity was increased from 17.24 to 19.8 °T due to capillarity action, providing a timely warning to consumers. The prepared colorimetric porous intelligent cellulose-based label is suitable for monitoring of MF.
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Background: Understanding the compliance of infected individuals and the psychological process underlying compliance during pandemics is important for preventing and controlling the spread of pathogens. Our study investigated whether fundamental social motives mediate the relationship between having infectious disease and compliance. Methods: An online survey was conducted in March 2020, during the severe phase of the COVID-19 outbreak in China to collect data from 15,758 participants. The survey comprised self-report questionnaires with items pertaining to current symptoms (COVID-19 symptoms, other symptoms or no symptoms), the Fundamental Social Motive Inventory, and measures of compliance. Correlation analysis, linear regression analysis, and structural equation model were used for data analysis. Results: The participants with COVID-19 symptoms had lower levels of compliance than those without symptoms, and their lower compliance was caused by a decrease in disease avoidance (indirect effect = -0.058, 95% CI = [-0.061, -0.056]) and familial motives (indirect effect = -0.113, 95% CI = [-0.116, -0.062]). Whereas exclusion concern (indirect effect = 0.014, 95% CI = [0.011, 0.017]) suppressed the effects of COVID-19 symptoms on compliance, the effect disappeared in the multiple mediation model, while those of disease avoidance and familial motives remained. Conclusion: Our findings emphasize the critical role of disease avoidance and familial motives in promoting compliance with public health norms during pandemics and suggest that enhancing these motives may serve as an effective intervention strategy to mitigate noncompliance among potentially infected individuals.
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This study aimed to delineate cortico-striato-thalamo-cerebellar network profiles based on static and dynamic connectivity analysis in genetic generalized and focal epilepsies with generalized tonic-clonic seizures, and to evaluate its potential for distinguishing these two epilepsy syndromes. A total of 342 individuals participated in the study (114 patients with genetic generalized epilepsy with generalized tonic-clonic seizures (GE-GTCS), and 114 age- and sex-matched patients with focal epilepsy with focal to bilateral tonic-clonic seizure (FE-FBTS), 114 healthy controls). Resting-state fMRI data were examined through static and dynamic functional connectivity (dFC) analyses, constructing cortico-striato-thalamo-cerebellar networks. Network patterns were compared between groups, and were correlated to epilepsy duration. A pattern-learning algorithm was applied to network features for classifying both epilepsy syndromes. FE-FBTS and GE-GTCS both presented with altered functional connectivity in subregions of the motor/premotor and somatosensory networks. Among these two groups, the connectivity within the cerebellum increased in the static, while the dFC variability decreased; conversely, the connectivity of the thalamus decreased in FE-FBTS and increased in GE-GTCS in the static state. Connectivity differences between patient groups were mainly located in the thalamus and cerebellum, and correlated with epilepsy duration. Support vector machine (SVM) classification had accuracies of 66.67%, 68.42%, and 77.19% when using static, dynamic, and combined approaches to categorize GE-GTCS and FE-GTCS. Network features with high discriminative ability predominated in the thalamic and cerebellar connectivities. The network embedding of the thalamus and cerebellum likely plays an important differential role in GE-GTCS and FE-FBTS, and could serve as an imaging biomarker for differential diagnosis.
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Brain structural covariance network (SCN) can delineate the brain synchronized alterations in a long-range time period. It has been used in the research of cognition or neuropsychiatric disorders. Recently, causal analysis of structural covariance network (CaSCN), winner-take-all and cortex-subcortex covariance network (WTA-CSSCN), and modulation analysis of structural covariance network (MOD-SCN) have expended the technology breadth of SCN. However, the lack of user-friendly software limited the further application of SCN for the research. In this work, we developed the graphical user interface (GUI) toolkit of brain structural covariance connectivity based on MATLAB platform. The software contained the analysis of SCN, CaSCN, MOD-SCN, and WTA-CSSCN. Also, the group comparison and result-showing modules were included in the software. Furthermore, a simple showing of demo dataset was presented in the work. We hope that the toolkit could help the researchers, especially clinical researchers, to do the brain covariance connectivity analysis in further work more easily.
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Highly efficient shielding materials with an excellent electromagnetic wave absorption have gained increased attention. A new design was used to provide cellulose paper with a high electromagnetic shielding effectiveness (EMI SE) and improve the absorption performance by constructing an asymmetry sandwich structure that consisted of a dense nickel coating, Fe3O4 nanoparticles and a porous nickel layer. This unique structure caused a "multiple reflection-absorb-reflection" process when the electromagnetic waves penetrated the sample. The EMI absorption (SEA) and total SE (SET) increased with Fe3O4 absorption time increasing at 8.2-12.4 GHz, which was attributed to the synergistic effect between porous nickel layer and Fe3O4 nanoparticles. The SEA and SET of the sample with a thickness of 0.195 mm can achieved 18.57 and 41.88 dB, respectively. The design was conducive to improving the magnetic and corrosion resistance properties. This study provided a novel path to obtain a low cost and lightweight electromagnetic shielding material that can reduce secondary radiation.
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Celulosa/química , Óxido Ferrosoférrico/química , Níquel/química , Protectores contra Radiación/química , Conductividad Eléctrica , Campos Electromagnéticos , Magnetismo , Nanopartículas del Metal/química , Porosidad , Propiedades de Superficie , TemperaturaRESUMEN
The functional design of paper-based material surfaces with renewable functions and environmentally friendly properties is prevalent nowadays. Herein, a superhydrophobic surface with a coral reef-like structure was prepared on filter paper by electroless copper plating, rapid silver nitrate etching, and facile 1-hexadecanethiol impregnation. After low-surface-energy thiol treatment, this unique coral reef-like structure surface showed excellent superhydrophobicity with a water contact angle of 163.8° and superoleophobicity with an oil contact angle of 0°, which could be used for oil-water separation and had a separation efficiency above 89.17% after 12 consecutive oil-water separations. Because the copper layer and silver nanostructure are both excellent conductive materials, the modified paper exhibited excellent electromagnetic shielding properties, and the electromagnetic interface shielding effectiveness exceeded 63 dB from 9 kHz to 1.5 GHz. The modified paper also had excellent self-cleaning properties and a better corrosion resistance. The unique three-dimensional interweaving structure between the cellulose fibers in the filter paper is fully utilized, and the substitution reaction between the silver ion and the copper coating produces a coral reef-like structure, which provides a new strategy for promoting the wide application of paper-based materials.
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Sustainable low-cost cellulose-based electronics has exhibited brighter prospects. In this study, a laminated felt-like electromagnetic shielding material was prepared by using cellulose paper as the matrix through the self-foaming effect in electroless nickel plating process in which an efficient palladium-free activation was conducted that alkaline sodium borohydride (NaBH4) reduced nickel ions into nickel cluster to initiate the plating process. NaOH concentration in NaBH4 solution, pH of the plating bath and the plating time affected the thickness, metal deposition and surface resistance of the electromagnetic shielding material. By understanding the morphology, inner structure, chemical component and thermal stability, the pH in the plating solution is a key for the preparation. When the pH was 8.51, the electromagnetic shielding effective reached 65 dB in the frequency ranges of 9 kHz to 1.5 GHz, which could shield more than 99.99% electromagnetic radiation. This work offers a novel and feasible path to develop functional cellulose-based materials.