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The intercalation capacity of a porous electrode in real batteries is not uniform spatially due to the inevitable structural and compositional inhomogeneity and site-dependent ion and electron transport features. Reliable methods to quantify the capacity distribution are highly desirable but absent so far in battery research. In this paper, a novel optical technique, oblique incident reflection difference (OIRD), was employed to monitor in situ the electrochemical ion (de)intercalation behavior of Prussian blue analogue (PBA) porous films. The OIRD signal responded synchronously to the ion (de)intercalation, and the change in the OIRD signal (ΔI) was positively correlated with the local electrochemical capacity, thereby enabling mapping of the spatially resolved ion storage capacity of the films. Optical analysis further showed that the OIRD response originated from the ion (de)intercalation-induced dielectric constant change of PBA films. This work therefore offers an intriguing in situ and spatially resolved tool for the study of rechargeable batteries.
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OBJECTIVE: Migraine has been demonstrated to exhibit abnormal functional connectivity of large-scale brain networks, which is closely associated with its pathophysiology and has not yet been explored by edge functional connectivity. We used an edge-centric approach combined with motif analysis to evaluate higher-order communication patterns of brain networks in migraine. METHODS: We investigated edge-centric metrics in 108 interictal migraine patients and 71 healthy controls. We parcellated the brain into networks using independent component analysis. We applied edge graph construction, k-means clustering, community overlap detection, graph-theory-based evaluations, and clinical correlation analysis. We conducted motif analysis to explore the interactions among regions, and a classification model to test the specificity of edge-centric results. RESULTS: The normalized entropy of lateral thalamus was significantly increased in migraine, which was positively correlated with the baseline headache duration, and negatively correlated with headache duration reduction following preventive medications at 3-month follow-up. Network-wise entropy of the sensorimotor network was significantly elevated in migraine. The community similarity between lateral thalamus and postcentral gyrus was enhanced in migraine. Migraine patients showed overrepresented L-shape and diverse motifs, and underrepresented forked motifs with lateral thalamus serving as the reference node. Furthermore, migraine patients presented with overrepresented L-shape triads, where the postcentral gyrus shared different edges with the lateral thalamus. The classification model showed that entropy of the lateral thalamus had the highest discriminative power, with an area under the curve of 0.86. INTERPRETATION: Our findings indicated an abnormal higher-order thalamo-cortical communication pattern in migraine patients. The thalamo-cortical-somatosensory disturbance of concerted working may potentially lead to aberrant information flow and deficit pain processing of migraine. ANN NEUROL 2023;94:1168-1181.
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Imageamento por Ressonância Magnética , Transtornos de Enxaqueca , Humanos , Imageamento por Ressonância Magnética/métodos , Transtornos de Enxaqueca/diagnóstico por imagem , Encéfalo , Tálamo/diagnóstico por imagem , CefaleiaRESUMO
Fe-doped Ni (oxy)hydroxide shows intriguing activity toward oxygen evolution reaction (OER) in alkaline solution, yet it remains challenging to further boost its performance. In this work, a ferric/molybdate (Fe3+ /MoO4 2- ) co-doping strategy is reported to promote the OER activity of Ni oxyhydroxide. The reinforced Fe/Mo-doped Ni oxyhydroxide catalyst supported by nickel foam (p-NiFeMo/NF) is synthesized via a unique oxygen plasma etching-electrochemical doping route, in which precursor Ni(OH)2 nanosheets are first etched by oxygen plasma to form defect-rich amorphous nanosheets, followed by electrochemical cycling to trigger simultaneously Fe3+ /MoO4 2- co-doping and phase transition. This p-NiFeMo/NF catalyst requires an overpotential of only 274 mV to reach 100 mA cm-2 in alkaline media, exhibiting significantly enhanced OER activity compared to NiFe layered double hydroxide (LDH) catalyst and other analogs. Its activity does not fade even after 72 h uninterrupted operation. In situ Raman analysis reveals that the intercalation of MoO4 2- is able to prevent the over-oxidation of NiOOH matrix from ß to γ phase, thus keeping the Fe-doped NiOOH at the most active state.
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BACKGROUND: Although headache disorders are common, the current diagnostic approach is unsatisfactory. Previously, we designed a guideline-based clinical decision support system (CDSS 1.0) for diagnosing headache disorders. However, the system requires doctors to enter electronic information, which may limit widespread use. METHODS: In this study, we developed the updated CDSS 2.0, which handles clinical information acquisition via human-computer conversations conducted on personal mobile devices in an outpatient setting. We tested CDSS 2.0 at headache clinics in 16 hospitals in 14 provinces of China. RESULTS: Of the 653 patients recruited, 18.68% (122/652) were suspected by specialists to have secondary headaches. According to "red-flag" responses, all these participants were warned of potential secondary risks by CDSS 2.0. For the remaining 531 patients, we compared the diagnostic accuracy of assessments made using only electronic data firstly. In Comparison A, the system correctly recognized 115/129 (89.15%) cases of migraine without aura (MO), 32/32 (100%) cases of migraine with aura (MA), 10/10 (100%) cases of chronic migraine (CM), 77/95 (81.05%) cases of probable migraine (PM), 11/11 (100%) cases of infrequent episodic tension-type headache (iETTH), 36/45 (80.00%) cases of frequent episodic tension-type headache (fETTH), 23/25 (92.00%) cases of chronic tension-type headache (CTTH), 53/60 (88.33%) cases of probable tension-type headache (PTTH), 8/9 (88.89%) cases of cluster headache (CH), 5/5 (100%) cases of new daily persistent headache (NDPH), and 28/29 (96.55%) cases of medication overuse headache (MOH). In Comparison B, after combining outpatient medical records, the correct recognition rates of MO (76.03%), MA (96.15%), CM (90%), PM (75.29%), iETTH (88.89%), fETTH (72.73%), CTTH (95.65%), PTTH (79.66%), CH (77.78%), NDPH (80%), and MOH (84.85%) were still satisfactory. A patient satisfaction survey indicated that the conversational questionnaire was very well accepted, with high levels of satisfaction reported by 852 patients. CONCLUSIONS: The CDSS 2.0 achieved high diagnostic accuracy for most primary and some secondary headaches. Human-computer conversation data were well integrated into the diagnostic process, and the system was well accepted by patients. The follow-up process and doctor-client interactions will be future areas of research for the development of CDSS for headaches.
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Cefaleia Histamínica , Sistemas de Apoio a Decisões Clínicas , Transtornos da Cefaleia Secundários , Transtornos da Cefaleia , Transtornos de Enxaqueca , Enxaqueca com Aura , Cefaleia do Tipo Tensional , Humanos , Cefaleia do Tipo Tensional/diagnóstico , Transtornos da Cefaleia/diagnóstico , Cefaleia/diagnóstico , Transtornos de Enxaqueca/diagnóstico , ComputadoresRESUMO
The integration of highly luminescent CsPbBr3 quantum dots on nanowire waveguides has enormous potential applications in nanophotonics, optical sensing, and quantum communications. On the other hand, CsPb2 Br5 nanowires have also attracted a lot of attention due to their unique water stability and controversial luminescent property. Here, the growth of CsPbBr3 nanocrystals on CsPb2 Br5 nanowires is reported first by simply immersing CsPbBr3 powder into pure water, CsPbBr3- γ Xγ (X = Cl, I) nanocrystals on CsPb2 Br5 -γ Xγ nanowires are then synthesized for tunable light sources. Systematic structure and morphology studies, including in situ monitoring, reveal that CsPbBr3 powder is first converted to CsPb2 Br5 microplatelets in water, followed by morphological transformation from CsPb2 Br5 microplatelets to nanowires, which is a kinetic dissolution-recrystallization process controlled by electrolytic dissociation and supersaturation of CsPb2 Br5 . CsPbBr3 nanocrystals are spontaneously formed on CsPb2 Br5 nanowires when nanowires are collected from the aqueous solution. Raman spectroscopy, combined photoluminescence, and SEM imaging confirm that the bright emission originates from CsPbBr3 -γ Xγ nanocrystals while CsPb2 Br5 -γ Xγ nanowires are transparent waveguides. The intimate integration of nanoscale light sources with a nanowire waveguide is demonstrated through the observation of the wave guiding of light from nanocrystals and Fabry-Perot interference modes of the nanowire cavity.
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BACKGROUND: Resting-state EEG microstates are thought to reflect brief activations of several interacting components of resting-state brain networks. Surprisingly, we still know little about the role of these microstates in migraine. In the present study, we attempted to address this issue by examining EEG microstates in patients with migraine without aura (MwoA) during the interictal period and comparing them with those of a group of healthy controls (HC). METHODS: Resting-state EEG was recorded in 61 MwoA patients (50 females) and 66 HC (50 females). Microstate parameters were compared between the two groups. We computed four widely identified canonical microstate classes A-D. RESULTS: Microstate classes B and D displayed higher time coverage and occurrence in the MwoA patient group than in the HC group, while microstate class C exhibited significantly lower time coverage and occurrence in the MwoA patient group. Meanwhile, the mean duration of microstate class C was significantly shorter in the MwoA patient group than in the HC group. Moreover, among the MwoA patient group, the duration of microstate class C correlated negatively with clinical measures of headache-related disability as assessed by the six-item Headache Impact Test (HIT-6). Finally, microstate syntax analysis showed significant differences in transition probabilities between the two groups, primarily involving microstate classes B, C, and D. CONCLUSIONS: By exploring EEG microstate characteristics at baseline we were able to explore the neurobiological mechanisms underlying altered cortical excitability and aberrant sensory, affective, and cognitive processing, thus deepening our understanding of migraine pathophysiology.
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Eletroencefalografia , Transtornos de Enxaqueca , Biomarcadores , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Feminino , Humanos , Transtornos de Enxaqueca/diagnóstico por imagemRESUMO
BACKGROUND: Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA) have not been evaluated sufficiently due to limited data, particularly in China. METHODS: Patients with SUNCT or SUNA treated in a tertiary headache centre or seven other headache clinics of China between April 2009 and July 2022 were studied; we compared their demographics and clinical phenotypes. RESULTS: The 45 patients with SUNCT and 31 patients with SUNA had mean ages at onset of 37.22 ± 14.54 years and 42.45 ± 14.72 years, respectively. The mean ages at diagnosis of SUNCT and SUNA were 41.62 ± 12.70 years and 48.68 ± 13.80 years, respectively (p = 0.024). The correct diagnosis of SUNCT or SUNA was made after an average of 2.5 (0-20.5) years or 3.0 (0-20.7) years, respectively. Both diseases had a female predominance (SUNCT: 1.14:1; SUNA: 2.10:1). The two diseases differed in the most common attack site (temporal area in SUNCT, p = 0.017; parietal area in SUNA, p = 0.002). Qualitative descriptions of the attacks included stabbing pain (44.7%), electric-shock-like pain (36.8%), shooting pain (25.0%), and slashing pain (18.4%). Lacrimation was the most common autonomic symptom in both SUNCT and SUNA patients, while eyelid oedema, ptosis, and miosis were less frequent. Triggers such as cold air and face washing were shared by the two diseases, and they were consistently ipsilateral to the attack site. CONCLUSIONS: In contrast to Western countries, SUNCT and SUNA in China have a greater female predominance and an earlier onset. The shared core phenotype of SUNCT and SUNA, despite their partial differences, suggests that they are the same clinical entity.
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Neuralgia , Síndrome SUNCT , Feminino , Masculino , Humanos , Estudos Transversais , Síndrome SUNCT/diagnóstico , Síndrome SUNCT/tratamento farmacológico , Cefaleia , China/epidemiologiaRESUMO
BACKGROUND: The aim of the study was to investigate whether MwoA and MwA are different manifestations of a single disease, distinct clinical entities, or located at two poles of a spectrum. METHODS: In this cross-sectional study, 5438 patients from 10 hospitals in China were included: 4651 were diagnosed with migraine without aura (MwoA) and 787 with migraine with aura (MwA). We used a validated standardized electronic survey to collect multidimensional data on headache characteristics and evaluated the similarities and differences between migraine subtypes. To distinguish migraine subtypes, we employed correlational analysis, factor analysis of mixed data (FAMD), and decision tree analysis. RESULTS: Compared to MwA, MwoA had more severe headaches, predominantly affected females, were more easily produced by external factors, and were more likely to have accompanying symptoms and premonitory neck stiffness. Patients with MwA are heterogeneous, according to correlation analysis; FAMD divided the subjects into three clear clusters. The majority of the differences between MwoA and MwA were likewise seen when typical aura with migraine headache (AWM) and typical aura with non-migraine headache (AWNM) were compared. Furthermore, decision trees analysis revealed that the chaotic MwA data reduced the decision tree's accuracy in distinguishing MwoA from MwA, which was significantly increased by splitting MwA into AWM and AWNM. CONCLUSIONS: The clinical phenomics of headache phenotype varies gradually from MwoA to AWM and AWNM, and AWM is a mid-state between MwoA and AWNM. We tend to regard migraine as a spectrum disorder, and speculate that different migraine subtypes have different "predominant regions" that generate attacks.
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Epilepsia , Enxaqueca com Aura , Enxaqueca sem Aura , Estudos Transversais , Epilepsia/complicações , Feminino , Cefaleia/complicações , Humanos , Enxaqueca com Aura/complicações , Enxaqueca com Aura/diagnóstico , Enxaqueca com Aura/genética , Enxaqueca sem Aura/diagnóstico , FenômicaRESUMO
OBJECTIVE: To observe the prevalence and characteristics of premonitory symptoms in Chinese migraineurs and explore their associations with migraine-related factors. METHOD: Migraineurs who visited a tertiary headache clinic and one of nine neurology clinics between May 2014 and November 2019 were studied. RESULT: Among the 4821 patients meeting the migraine criteria (International Classification of Headache Disorders, 3rd edition), 1038 (21.5%) patients experienced at least one premonitory symptom. The most common premonitory symptoms were neck stiffness, dizziness, yawning and drowsiness. The logistic regression analysis demonstrated that aura, photophobia, aggravation by routine physical activity, triggers, family history, depression, coffee consumption and physical exercise were associated with an increased probability of experiencing premonitory symptoms (p ≤ 0.001). The premonitory symptoms of migraine with and without aura differ in prevalence and most common symptoms. The cluster analysis revealed pairwise clustering of the following premonitory symptoms: Photophobia/phonophobia, concentration change/dysesthesia, loquacity/overactivity, yawning/drowsiness, fatigue/dizziness, and mood change/irritability. The correlation analysis of triggers and premonitory symptoms revealed that temperature change, environment change, sleep disorder, activity and stress were related to multiple premonitory symptoms, and that food, light, menstruation, alcohol and odor were related to special premonitory symptoms (p ≤ 0.001). CONCLUSION: The prevalence of premonitory symptoms among migraineurs in China is 21.5%. Some factors influence the probability of experiencing premonitory symptoms. Paired premonitory symptoms in the clustering analysis may share similar origins. Certain triggers associated with multiple premonitory symptoms may induce brain dysfunction; however, other triggers that overlap with corresponding special premonitory symptoms may be premonitory symptoms or a form of premonitory symptom.
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Fadiga/epidemiologia , Transtornos de Enxaqueca/epidemiologia , Enxaqueca com Aura/epidemiologia , Enxaqueca sem Aura/epidemiologia , Fotofobia/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , China/epidemiologia , Tontura , Feminino , Cefaleia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , BocejoRESUMO
BACKGROUND: As a disorder of brain dysfunction, migraine has been associated with cognitive decline. However, no consistent results with respect to the attention function in migraineurs have been found, and the relationship between attentional inhibition and migraine is also unclear. In this study, the attentional inhibition function was evaluated using event-related potentials (ERPs) while migraine patients and healthy controls were performing the color-word Stroop task. METHODS: In this study, 75 migraine patients and 41 age-, gender-, and education-matched healthy controls were enrolled. The Stroop task was performed, and both behavioral and ERP data were analyzed. RESULTS: As to the behavioral data, the migraine group had a longer reaction time compared to the control group, but no difference in Stroop effect was observed. With respect to ERP components, the amplitudes of both early and late medial frontal negativity (MFN) were decreased in the migraine group. Additionally, obvious differences in the early MFN and sustained potential (SP) amplitudes were found between patients with and without allodynia. CONCLUSIONS: At the behavioral level, migraine patients exhibited decreased executive ability but no obvious decline in inhibition. By contrast, a decline in attentional inhibition during the migraine interictal phase was confirmed by the analysis of ERP components, mainly those associated with changes in the conflict-monitoring stage, independent of confounding factors such as age, education, medication and mood disorders. Migraine patients with allodynia exhibited some significant differences in early MFN and SP compared to those without, supporting the hypothesis that migraine chronification aggravates the decline in attentional inhibition.
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Potenciais Evocados , Transtornos de Enxaqueca , Atenção , Humanos , Tempo de Reação , Teste de StroopRESUMO
In the article, we report the photoluminescence (PL) properties of D and S defects induced by Si+/Ni+ ions co-implanting into the top Si film of the silicon-on-insulator (SOI) wafer. Variable-temperature PL spectra of these co-implanted SOI samples indicate that the light emitting from the D defects can be observed as high as 273 K. In comparison with the other ion-implantation, the Si+/Ni+ ion-co-implantation optimizes luminescent temperature stability of the both D and S defects and purifies the S defect type in silicon then effectively restrains the spectral broadening of the S-line in PL spectra. The depth distribution of the D and S defects along the normal direction of SOI surface at the corresponding ion-implantation energy has been well depicted by detecting the PL signals of the layer-by-layer etched SOI surface, respectively. These results provide valuable information to fabricate SOI-based infrared light sources for optical fiber communications.
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BACKGROUND: Neuronal intranuclear inclusion disease (NIID) is considered a heterogeneous disease because of its highly variable clinical manifestations. To date, there are no reports of NIID patients presenting with hemiplegic migraine (HM)-like headache, or of HM and NIID co-occurring as comorbidity, and the connection between these 2 seemingly unrelated clinical conditions has yet to be established. METHOD: We present a patient with NIID who was previously diagnosed with HM. To determine the pathogenesis of HM in this NIID patient, we systematically reviewed published NIID and HM cases and cataloged them based on their clinical manifestations. RESULT: The clinical manifestations of NIID is highly various; however, there is no case reported to date that shows HM-like symptoms or cerebral edema. All documented symptomatic HM cases show vascular dysfunction to various degrees, but none of them has been shown to be correlated with NIID. CONCLUSION: Our patient is the first documented case in which HM and NIID occur simultaneously. Vascular dysfunctions that cause cerebral hypoperfusion and glucose hypometabolism, two of the dominant causes of symptomatic HM, may be associated with the accumulation of eosinophilic hyaline inclusions that cause NIID. However, the existence of inclusions may also alter neuronal behavior and indirectly cause cerebral hypoperfusion and glucose hypometabolism. Further research and observations are needed to examine the relationship between HM and NIID.
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Transtornos Cerebrovasculares , Hemiplegia , Enxaqueca com Aura , Doenças Neurodegenerativas , Adulto , Edema Encefálico/diagnóstico , Edema Encefálico/epidemiologia , Edema Encefálico/etiologia , Transtornos Cerebrovasculares/complicações , Transtornos Cerebrovasculares/epidemiologia , Comorbidade , Hemiplegia/diagnóstico , Hemiplegia/epidemiologia , Hemiplegia/etiologia , Humanos , Corpos de Inclusão Intranuclear , Masculino , Enxaqueca com Aura/diagnóstico , Enxaqueca com Aura/epidemiologia , Enxaqueca com Aura/etiologia , Doenças Neurodegenerativas/complicações , Doenças Neurodegenerativas/diagnóstico , Doenças Neurodegenerativas/epidemiologia , Adulto JovemRESUMO
BACKGROUND: Migraine is characterized by a hypersensitivity to environmental stimulation which climaxes during headache attacks but persists during attack-free period. Despite ongoing debates about the nature of the mechanisms giving rise to this abnormality, the presence of deficient inhibitory cortical processes has been proposed to be one possible mechanism underlying its pathogenesis. Empirical evidence supporting this claim is mainly based on previous accounts showing functional cortical disexcitability in the sensory domain. Considering that a general inhibitory control process can play an important role across early to later stage of information processing, this may indicate the important role other dimensions of inhibitory control can play in migraine disability. The present study examined the pathophysiological features of inhibitory control that takes place during suppression of prepotent responses in migraineurs. METHODS: Twenty-two patients with migraine without aura (mean age = 30.86 ± 5.69 years; 19 females) during the interictal period and 25 healthy controls (mean age = 30.24 ± 3.52 years; 18 females) were recruited. We used a stop signal task in combination with event-related potentials (ERPs) to examine participants' neural activity supporting response inhibition. RESULTS: Behaviorally, migraineurs exhibited prolonged stop signal reaction times relative to healthy controls. At the neural level, the amplitude of the stop-N2 over fronto-central, central and centro-parietal scalp regions, a component of the ERPs related to conflict monitoring during early, non-motoric stages of inhibition, was significantly increased in migraineurs. Meanwhile, the amplitude of the stop-P3 over central and centro-parietal scalp regions, a component of the ERPs reflecting late-stage inhibition of the motor system and cognitive evaluation of motor inhibition, was also significantly increased in migraineurs. Ultimately, our time-frequency analysis further revealed increased delta activity in migraineurs. CONCLUSIONS: Consistent with the theory that alterations in cognitive cortical processes are a key signature of migraine, our findings revealed an abnormal state of suppressing prepotent responses in migraineurs, which can be attributed to cortical disexcitability of the pre-frontal executive network and centro-parietal sensorimotor network. These novel findings extend to show the existence of dysfunctional inhibition control that occurs during suppression of prepotent responses in migraneurs.
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Potenciais Evocados , Transtornos de Enxaqueca , Feminino , Humanos , Inibição Neural , Lobo Parietal , Tempo de ReaçãoRESUMO
Quantum dots/graphene (QDs/Gr) composites have become the research hotspot recently due to their unique synergistic effect as optical absorption material for next-generation electronic and optoelectronic devices. In this work, Ge QDs/Gr composite is prepared by a simple and effective ion-beam sputtering deposition technique. The intact growth evolution process is detailly investigated by means of the effect of Ge deposition amount, which will induce the enhanced crystallinity in QDs and the reduced defects in graphene. Moreover, a feasible and inspiring strategy to effectively tune doping in graphene by artificial control through changing the deposition amount of Ge atoms on graphene is demonstrated. In addition, charge transfer and interaction strength at the interface of Ge QD and graphene is influenced via the oxygen defect in the QD surface, which is consistent with field-effect transistor test and first-principle calculations. The p-doping characteristics of graphene decorated by Ge QDs may have significant application prospects in energy band engineering of graphene-based building blocks for graphene-based composite development and near-infrared detector applications.
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Background - Headache may be due to either a primary or secondary disorder, and neuroimaging assessments can play an important role when differentiating between these types of headache. Although many studies have reported no significant differences between primary headache patients and the general population in terms of abnormal neuroimaging findings, others have shown that neuroimaging may be employed to rule out secondary causes of headache that could impact morbidity and mortality. This issue remains under debate. Thus, the present study compared the neuroimaging findings of headache patients and healthy controls. Methods - This study recruited 1070 healthy controls and 1070 primary headache patients from the Chinese People's Liberation Army General Hospital. The primary headache patients were diagnosed by computerized clinical decision support systems, and re-diagnosed by a specialist. All participants were assessed with either computed tomography or magnetic resonance imaging (MRI) scans. The neuroimaging findings were classified as significant abnormalities, non-significant abnormalities, or normal. Results - All the significant abnormalities were found using MRI scans. Significant abnormalities were identified in 4 primary headache patients (0.58%) and 5 healthy controls (0.73%); the rate of significant abnormalities was not significant different between both groups (P > .05). Conclusions - The present study found that neuroimaging was unnecessary for the primary headache patients.
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Encéfalo/diagnóstico por imagem , Cefaleia/diagnóstico por imagem , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem/métodosRESUMO
The photoluminescence (PL) properties of silicon-on-insulator (SOI) samples, modified by the Si+ self-ion-implantation (SII) into Si thin film followed by annealing, have been well investigated. The well-known W-line can also be observed in SII SOI samples, its emitting behavior and structural evolution have been discussed in this article. The parallel PL pattern trend and the similar changes of temperature-dependent intensity suggest that luminescence center of I1 and I2 peaks located in the near-infrared band originates from the same interstitial-clusters (InCs). The PL peak at 1.762 eV can be ascribed to the quantum confinement (QC) from small-sized Si nanocrystals. Based on the electron spin resonance (ESR) experiments and the variation of normalized PL intensities at different annealing temperature (TA), the neutral oxygen vacancy (NOV) [O3≡Si-Si≡O3] is proposed to be responsible for the blue emission of P2 and P3 peaks, whose intensity can be restrained by the existence of the paramagnetic E1' defects [O3≡Si+]. The density of E1' defect is found to reduce with the increase of annealing temperature (TA). Our results provide a useful method to identify the origin of luminescence centers and pave a way for the application of new type optical defects on silicon based light emitting devices (LEDs).
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A series of zero-dimensional Ge/Si quantum dots (QDs) samples are fabricated by inducing the transformation from the two-dimensional Ge thin film, which is grown by the traditional direct current (DC) magnetron sputtering, via regulating the annealing process. The QD density increases sharply after the post rapid thermal annealing (PRTA). The observations of atomic force microscopy (AFM) and Raman spectroscopy suggest that the good morphology of Ge QDs results from an appropriate thermodynamics and kinetics surrounding shaped by the cooperative interaction of the Ge-Si lattice mismatch, the film's surface temperature, and the difference in thermal expansion coefficients between Ge and Si. The photoluminescence (PL) peaks of Ge QDs are detected in monolayer Ge QDs with ultrahigh density at 17 K. The Metal-Ge/Si QDs-Metal (MGM) photodetector fabricated from the ultrahigh-density QDs sample exhibits a relatively high current gain, absolute photoelectric responsivity, and internal quantum efficiency (IQE). Our results demonstrate that the high-quality Ge QDs with strong light absorption and quantum confinement effect can be realized by modulating DC magnetron sputtering and the PRTA process. This paves the way for realizing silicon-based optoelectronic devices with high performance by the traditional, relatively low-cost, and large-scale production nanomaterial fabricating method.
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OBJECTIVE: To investigate the association between congenital heart defects (CHDs) and migraine and evaluate the efficacy of transcatheter defect closure from a new perspective. METHODS: The patients with CHDs who underwent transcatheter defect closure were screened in the medical database of Chinese PLA General Hospital from January 2006 to January 2017. The assessment included basic admission information, the 3-item ID Migraine Screener, and a detailed questionnaire administered by telephone or in an outpatient clinic. Patients were divided into ventricular septal defect (VSD) group and AP group (ie, patients with ASD or PFO) based on the type of defects. The latter group could be further divided into right-to-left shunt (RLS) group and left-to-right (LRS) shunt group. Each group contained 4 subgroups according to their migraine diagnosis before and after defect closure: persistent migraine (PM), relieved migraine (RM), without migraine (WM), and new-onset migraine (NM). RESULTS: The study recruited total 441 CHDs patients. Most patients in RLS group had migraine before and/or after surgery (76.4%, 42/55) and the proportion of them in NM group was higher than that of in LRS group (23.5%, 4/17 vs 6.8%, 18/266, P = .0418). Although the size of closure device or defect did not show significant differences, the ratios (R = size of closure/size of defect) were significantly higher in NM group than those in WM group (1.40 [1.26, 1.80] vs 1.22 [1.13, 1.38] in AP group, P = .00238; 1.38 [1.23, 1.50] vs 1.22 [1.13, 1.37] in LRS group, P = .024934, respectively). Further logistic regression analysis illustrated that larger R value was a risk factor for NM in AP group (OR 1.48, 95% CI 1.07-2.05, P = .0188). Besides, migraine symptoms decreased significantly after defect closure in PM group among patients with ASD and PFO. CONCLUSION: This study revealed several associations between migraine and CHDs, especially the large ratio of closure device size to defect size. High-quality randomized controlled trials and animal studies are needed to further investigate and clarify the underlying association between CHDs and migraine.
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Forame Oval Patente/epidemiologia , Comunicação Interatrial/epidemiologia , Comunicação Interventricular/epidemiologia , Transtornos de Enxaqueca/epidemiologia , Adolescente , Adulto , Idoso , Cateterismo Cardíaco , Causalidade , Criança , Comorbidade , Forame Oval Patente/complicações , Forame Oval Patente/cirurgia , Comunicação Interatrial/complicações , Comunicação Interatrial/cirurgia , Comunicação Interventricular/complicações , Comunicação Interventricular/cirurgia , Humanos , Pessoa de Meia-Idade , Transtornos de Enxaqueca/etiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco , Dispositivo para Oclusão Septal , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Migraine is a chronic neurological disorder. However, its pathogenesis is still unclear. This study aimed to measure the posterior ocular structure in patients with migraine using enhanced depth imaging (EDI)-optical coherence tomography (OCT) and explore the probable pathogenesis of migraine. METHODS: A total of 115 patients diagnosed with migraine and 50 healthy volunteers were recruited. These participants underwent an ocular examination to exclude the ocular diseases. Retinal nerve fiber layer thickness, macular thickness, and choroid thickness were assessed using EDI-OCT. RESULTS: The nasal peripapillary retinal nerve fiber layer (pRNFL) was significantly thinner in the migraine with aura group (p = 0.001) than that in the control group. The inferior inner macular layer was thinner in the migraine with aura group (p = 0.005). The 3 subfields of choroid were significantly thinner in the migraine with aura group (p = 0.044, 0.008, and 0.029). However, there was no difference between the migraine without aura group and the control group. The nasal pRNFL in migraine with aura was negatively correlated with the product of duration (months) and number of attacks/month (p = 0.039). CONCLUSION: The changes in the ocular posterior structure may serve as evidence of the trigeminovascular system mechanism underlying migraine and transneuronal retrograde degeneration of the primary visual cortex, which reflects the cortical spreading depression.
Assuntos
Corioide/patologia , Transtornos de Enxaqueca/patologia , Neurônios Retinianos/patologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Retina/patologia , Tomografia de Coerência ÓpticaRESUMO
BACKGROUND: There are sparse and limited studies on small sample size reporting the application of next-generation sequencing (NGS) in the detection of central nervous system (CNS) viral infections. We assessed the diagnostic performance of NGS of cerebrospinal fluid (CSF) for predicting viral infections of the CNS caused by the neurotropic herpes viruses in a pilot population. MATERIALS AND METHODS: We prospectively collected CSF samples from 24 patients with CNS viral infection from April 2017 to October 2018. Of the 24 patients, 19 patients were infected with herpes simplex virus 1 (HSV-1), 1 patient with HSV-2, and 4 patients with varicella-zoster virus (VZV). All CSF samples were screened for viral DNA using NGS technologies to detect viral CNS infections. RESULTS: Of the 24 patients with confirmed viral CNS infection caused by the neurotropic herpes viruses, 10 (10/24, 41.67%) patients exhibited positive NGS results. With the help of NGS, HSV-1 DNA was detected in the CSF of 6 patients (6/19; 31.58%). HSV-2 DNA was detected in 1 patient (1/1; 100%) and VZV DNA was detected in 3 patients (3/4; 75%). The positive rate of virus detected by NGS decreased with time. The positive rates of NGS of CSF in the first, second, and third weeks were 54.5% (6/11), 44.4% (4/9), and 0% (0/4), respectively. CONCLUSIONS: NGS method is a promising pathogen detection tool for identifying viral CNS infections. It should be recommended to sequence viral DNA of CSF in the early stage of CNS viral infections.