Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
      More Filters
      Clear All
      More Filters
      Source
    • Language
183 result(s) for "Guan, Zhi-Hong"
Sort by:
AM-MTEEG: multi-task EEG classification based on impulsive associative memory
Electroencephalogram-based brain-computer interfaces (BCIs) hold promise for healthcare applications but are hindered by cross-subject variability and limited data. This article proposes a multi-task (MT) classification model, AM-MTEEG, which integrates deep learning-based convolutional and impulsive networks with bidirectional associative memory (AM) for cross-subject EEG classification. AM-MTEEG deals with the EEG classification of each subject as an independent task and utilizes common features across subjects. The model is built with a convolutional encoder-decoder and a population of impulsive neurons to extract shared features across subjects, as well as a Hebbian-learned bidirectional associative memory matrix to classify EEG within one subject. Experimental results on two BCI competition datasets demonstrate that AM-MTEEG improves average accuracy over state-of-the-art methods and reduces performance variance across subjects. Visualization of neuronal impulses in the bidirectional associative memory network reveal a precise mapping between hidden-layer neuron activities and specific movements. Given four motor imagery categories, the reconstructed waveforms resemble the real event-related potentials, highlighting the biological interpretability of the model beyond classification.
Prevalence and risk factors of severe postpartum hemorrhage: a retrospective cohort study
Background Although maternal deaths are rare in developed regions, the morbidity associated with severe postpartum hemorrhage (SPPH) remains a major problem. To determine the prevalence and risk factors of SPPH, we analyzed data of women who gave birth in Guangzhou Medical Centre for Critical Pregnant Women, which received a large quantity of critically ill obstetric patients who were transferred from other hospitals in Southern China. Methods In this study, we conducted a retrospective case-control study to determine the prevalence and risk factors for SPPH among a cohort of women who gave birth after 28 weeks of gestation between January 2015 and August 2019. SPPH was defined as an estimated blood loss ≥1000 mL and total blood transfusion≥4 units. Logistic regression analysis was used to identify independent risk factors for SPPH. Results SPPH was observed in 532 mothers (1.56%) among the total population of 34,178 mothers. Placenta-related problems (55.83%) were the major identified causes of SPPH, while uterine atony without associated retention of placental tissues accounted for 38.91%. The risk factors for SPPH were maternal age < 18 years (adjusted OR [aOR] = 11.52, 95% CI: 1.51–87.62), previous cesarean section (aOR = 2.57, 95% CI: 1.90–3.47), history of postpartum hemorrhage (aOR = 4.94, 95% CI: 2.63–9.29), conception through in vitro fertilization (aOR = 1.78, 95% CI: 1.31–2.43), pre-delivery anemia (aOR = 2.37, 95% CI: 1.88–3.00), stillbirth (aOR = 2.61, 95% CI: 1.02–6.69), prolonged labor (aOR = 5.24, 95% CI: 3.10–8.86), placenta previa (aOR = 9.75, 95% CI: 7.45–12.75), placenta abruption (aOR = 3.85, 95% CI: 1.91–7.76), placenta accrete spectrum (aOR = 8.00, 95% CI: 6.20–10.33), and macrosomia (aOR = 2.30, 95% CI: 1.38–3.83). Conclusion Maternal age < 18 years, previous cesarean section, history of PPH, conception through IVF, pre-delivery anemia, stillbirth, prolonged labor, placenta previa, placental abruption, PAS, and macrosomia were risk factors for SPPH. Extra vigilance during the antenatal and peripartum periods is needed to identify women who have risk factors and enable early intervention to prevent SPPH.
Autoimmune Encephalitis: An Expanding Frontier of Neuroimmunology
INTRODUCTION Discovery of the spectrum ofautoimmune encephalitis (ALE) is among the most attractive events of neurology in the past decade. AIE includes a heterogeneous group of encephalitic syndromes, which generally include two major categories: classic paraneoplastic limbic encephalitis (LE) associated with the so-called well-characterized onconeural autoantibodies against intracellular neuronal antigens (e.g., Hu, Ma2, etc.) and new-type AIE associated with autoantibodies to the neuronal surface or synaptic antigens.
Bifurcations and chaos of a discrete-time model in genetic regulatory networks
In this paper, the dynamics of a discrete-time genetic model is investigated. The existence and stability conditions of the fixed points are obtained. It is shown that the discrete-time genetic network undergoes fold bifurcation, flip bifurcation and Neimark–Sacker bifurcation. The biological parameter and discretization step size are taken as bifurcation parameters, respectively, and the explicit bifurcation criteria are derived based on the center manifold theorem and bifurcation theory. Numerical simulations validate the theoretical analysis and also show that the system can exhibit diverse dynamic behaviors such as period-7, -14, -5, -10 orbits and chaos. The overall results reveal much richer dynamics of the discrete-time genetic model than that of the original continuous-time model.
Autoimmune glial fibrillary acidic protein astrocytopathy manifesting as subacute meningoencephalitis with descending myelitis: a case report
Background Glial fibrillary acidic protein (GFAP) autoimmune astrocytopathy is characterized by GFAP autoantibody positive encephalitis, meningoencephalitis or meningoencephalomyelitis. The initial clinical presentation may be similar to central nervous system infections making early diagnosis challenging. Case presentation A Chinese female patient presented with subacute meningitis with symptoms of headache, vomiting, and fever. Cerebrospinal fluid (CSF) analysis showed monocytic pleocytosis, elevated protein level, low glucose level, and negative basic microbiological studies including Xpert MTB/RIF. Brain magnetic resonance imaging (MRI) showed bilateral cerebral cortical and white matter hyperintensities on FLAIR sequences. The patient was diagnosed with possible tuberculous meningitis and started on anti-tuberculosis therapy (ATT). Three months later, the patient developed cervical myelopathy and encephalopathy with persistent CSF pleocytosis. Five months later, tissue-based and cell-based assays demonstrated GFAP antibodies in blood and CSF. Her symptoms improved with repeated administration of intravenous immunoglobulin (IVIG) and corticosteroids. One-and-a-half -year follow-up showed neither clinical progression nor relapses. Conclusions Anti-GFAP astrocytopathy should be included in the differential diagnosis of patients who present with subacute meningitis with negative microbiological studies and a progressive clinical course including encephalitis and/or myelitis.
Multi-tracking of second-order multi-agent systems using impulsive control
This paper investigates the multi-tracking of second-order multi-agent systems. A distributed impulsive protocol is designed to solve the multi-tracking problem, which utilizes only position sampled data of the agents and the desired trajectories. In the context of constant desired velocities, a necessary and sufficient condition on feedback gains and sampling period is obtained to guarantee uniform multi-tracking. In the context of time-varying desired velocities, multi-agent systems can reach bounded variable multi-tracking, in which the ultimate tracking error is proportional to the sampling period. Simulation examples are given to illustrate the theoretical analysis.
Limbic Encephalitis Associated with Anti-γ-aminobutyric Acid B Receptor Antibodies: A Case Series from China
Background: Autoimmune encephalitis associated with antibodies against γ-aminobutyric acid B receptor (GABA B R) in patients with limbic encephalitis (LE) was first described in 2010. We present a series of Han Chinese patients for further clinical refinement. Methods: Serum and cerebrospinal fluid (CSF) samples from patients referred to the program of encephalitis and paraneoplastic syndrome of Peking Union Medical College Hospital were tested with indirect immunofluorescence. Clinical information of patients with anti-GABA B R antibody positivity was retrospectively reviewed, and descriptive statistical analysis was performed. Results: All eighteen anti-GABA B R antibody-positive cases had limbic syndromes, and electroencephalogram (EEG) or neuroimaging evidence fulfilled the diagnostic criteria of LE. Four patients had additional antibodies against Hu in serum and one had anti-N-methyl-d-aspartate receptor antibody in both sera and CSF. Seventeen (17/18) patients presented with new-onset refractory seizure or status epileptics. Twelve (12/18) patients had memory deficits, 11 (11/18) patients had personality change, 7 (7/18) patients had disturbance of consciousness, and 3 (3/18) patients showed cerebellar dysfunction. One patient with LE had progressive motor and sensory polyneuropathy. Lung cancer was detected in 6 (6/18) patients. Ten (10/18) patients showed abnormality in bilateral or unilateral mediotemporal region on magnetic resonance imaging. Ten (10/18) patients had temporal lobe epileptic activity with or without general slowing on EEG. Seventeen patients received immunotherapy and 15 of them showed neurological improvement. Four patients with lung cancer died within 1-12 months due to neoplastic complications. Conclusions: Our study demonstrates that most Han Chinese patients with anti-GABA B R antibody-associated LE have prominent refractory epilepsy and show neurological improvement on immunotherapy. Patients with underlying lung tumor have a relatively poor prognosis. Testing for anti-GABA B R antibodies is necessary for patients with possible LE or new-onset epilepsy with unknown etiology.
Utility and Safety of Intrathecal Methotrexate Treatment in Severe Anti-N-methyl-D-aspartate Receptor Encephalitis: A Pilot Study
Background: Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is a treatable autoimmune neurologic syndrome that occurs with or without tumor association. However, some severe cases are refractory to systemic immunotherapy. This pilot study aimed to evaluate the utility and safety of intrathecal methotrexate injection for severe patients with anti-NMDAR encephalitis who did not respond to first-line immunotherapy. Methods: Intrathecal injections with methotrexate and dexamethasone were performed weekly in four legible patients within consecutive 4 weeks. Cerebrospinal fluid (CSF) was collected at baseline and each time of intrathecal injection for identification of anti-NMDAR antibody titers. Results: Significant clinical improvement was observed in three patients associated with a stepwise decrease of CSF anti-NMDAR antibody titers (maximum: 1/320 to minimum: 1/10). After 2 months of follow-up, they were able to follow simple commands and had appropriate interactions with people (modified Rankin scale [mRS] of 0-2). At 12 months of follow-up, they all had returned to most activities of daily life (mRS of 0), and no relapses were reported. One patient showed no clinical improvement and died of neurologic complications. Conclusions: Intrathecal treatment may be a potentially useful supplementary therapy in severely affected patients with anti-NMDAR encephalitis. Further large cohort study and animal experiment may help us elaborate the utility of intrathecal injection of methotrexate and its mechanism of action.
Analysis of a new three-dimensional system with multiple chaotic attractors
In this paper, a new three-dimensional autonomous system with complex dynamical behaviors is reported. This new system has three quadratic nonlinear terms and one constant term. One remarkable feature of the system is that it can generate multiple chaotic and multiple periodic attractors in a wide range of system parameters. The presence of coexisting chaotic and periodic attractors in the system is investigated. Moreover, it is easily found that the new system also can generate four-scroll chaotic attractor. Some basic dynamical behaviors of the system are investigated through theoretical analysis and numerical simulation.
Distributed Estimator-Based Fault Detection for Multi-agent Networks
This paper focuses on the problem of fault detection (FD) for multi-agent networks when some follower agents are subjected to actuator or sensor faults. A distributed FD architecture is proposed by constructing a consensus-based estimator and the related residual. Using Lyapunov function method and Riccati equation, asymptotically stable condition for the novel estimator is derived, and the time-varying residual threshold for FD is determined. A numerical example is presented to illustrate the efficiency of the consensus-based approach for FD.