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1.
Vasc Med ; : 1358863X241227476, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38469820

RESUMO

BACKGROUND: External iliac artery endofibrosis (EIAE) is a rare vascular disease which has been traditionally seen in avid cyclists. The conventional approach has been surgery, although no high-quality evidence suggests superiority of surgery over percutaneous endovascular intervention. There are limited data on the efficacy of stenting in EIAE. METHODS: Over a 14-year period, we treated 10 patients (13 limbs) with EIAE with stents. These patients had declined surgery. The mean follow up was 8.4 ± 3.3 years. There were eight women. Five patients were competitive runners, three were cyclists, and two were triathletes. The mean age was 40.7 ± 2.9 years and body mass index was 19.46 ± 1.6. Intravascular ultrasound (IVUS) was used in eight limbs. RESULTS: Procedural success was achieved in all. The recurrence of symptoms occurred in three patients at a mean of 9.3 ± 2.1 months postindex intervention. The other seven patients remained symptom free. IVUS revealed a pathognomonic finding which we termed 'perfect circle appearance'. It results from symmetric or asymmetric hypertrophy of one or more layers of the arterial wall leading to negative remodeling, which creates a distinct echo dense structure contrasting itself from the luminal blood's echoluscent appearance. It is identical to IVUS images of diffuse venous stenosis with important implications in the treatment technique. CONCLUSIONS: We conclude that stenting in EIAE is safe and effective with a good long-term outcome. It can be an alternative to surgery, particularly in those patients who refuse a surgical approach. The IVUS image is pathognomonic and 'sine qua non' of EIAE.

2.
ISA Trans ; 144: 51-60, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38007369

RESUMO

Intent on the smart vehicles of a platoon to follow their correct routes, they must exchange their state information with each other based on a communication graph. Meanwhile, malicious factors like Denial-of-Service (DoS) attacks, one of the major types of cyber-attacks, can affect vehicles and divert them from their correct routes. Also, spreading the erroneous data induced by a DoS attack from the attacked agent gradually destabilizes the platoon. Therefore, preserving all vehicles' safety is a vital issue for the platoon. In this paper, in the first step, detection and measurement of the DoS attack modeled by a time-varying delay are conducted by exploiting two incremental counters through a DoS detection and measurement algorithm. Also, supplementary to this, a novel vehicular resilient control strategy based on switching systems is proposed to retrieve the attacked agent to the leader-follower consensus. In the end, the capability of the proposed algorithms will be indicated by presenting an illustrative case study.

3.
ISA Trans ; 110: 238-246, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33069373

RESUMO

A multi-microgrid system, including several microgrids and distributed energy resources, is always threatened by numbers of faults and attacks as a consequence of which malfunctioning can occur on a large scale. Thus, minimizing the effects of such disruptions is of paramount importance. This paper addresses the problem of mitigating a multi-microgrid system that faces false data injection and replay attacks by considering the multi-microgrid as a multi-agent system in which each microgrid as an agent represents a node in a weighted directed graph. The problem of consensus among normal agents is studied when microgrids and their communications are attacked. The malicious agents become isolated with the help of Weighted Mean Subsequence Reduced (W-MSR) algorithms in which all normal agents neglect the extreme values received from their neighbors. The proposed controller is able to maintain the system's desired performance when false data is injected into the system, or valid data is received with time-delays. Finally, numerical examples and simulation results are provided.

4.
Front Robot AI ; 7: 538347, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33501308

RESUMO

In this paper, a new scheme for multi-lateral remote rehabilitation is proposed. There exist one therapist, one patient, and several trainees, who are participating in the process of telerehabilitation (TR) in this scheme. This kind of strategy helps the therapist to facilitate the neurorehabilitation remotely. Thus, the patients can stay in their homes, resulting in safer and less expensive costs. Meanwhile, several trainees in medical education centers can be trained by participating partially in the rehabilitation process. The trainees participate in a "hands-on" manner; so, they feel like they are rehabilitating the patient directly. For implementing such a scheme, a novel theoretical method is proposed using the power of multi-agent systems (MAS) theory into the multi-lateral teleoperation, based on the self-intelligence in the MAS. In the previous related works, changing the number of participants in the multi-lateral teleoperation tasks required redesigning the controllers; while, in this paper using both of the decentralized control and the self-intelligence of the MAS, avoids the need for redesigning the controller in the proposed structure. Moreover, in this research, uncertainties in the operators' dynamics, as well as time-varying delays in the communication channels, are taken into account. It is shown that the proposed structure has two tuning matrices (L and D) that can be used for different scenarios of multi-lateral teleoperation. By choosing proper tuning matrices, many related works about the multi-lateral teleoperation/telerehabilitation process can be implemented. In the final section of the paper, several scenarios were introduced to achieve "Simultaneous Training and Therapy" in TR and are implemented with the proposed structure. The results confirmed the stability and performance of the proposed framework.

5.
Artif Intell Med ; 97: 143-151, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30587391

RESUMO

Continuous cuffless blood pressure (BP) monitoring has attracted much interest in finding the ideal treatment of diseases and the prevention of premature death. This paper presents a novel dynamical method, based on pulse transit time (PTT) and photoplethysmogram intensity ratio (PIR), for the continuous cuffless BP estimation. By taking the advantages of both the modeling and the prediction approaches, the proposed framework effectively estimates diastolic BP (DBP), mean BP (BP), and systolic BP (SBP). Adding past states of the cardiopulmonary system as well as present states of the cardiac system to our model caused two main improvements. First, high accuracy of the method in the beat to beat BP estimation. Second, notwithstanding noticeable BP changes, the performance of the model is preserved over time. The experimental setup includes comparative studies on a large, standard dataset. Moreover, the proposed method outperformed the most recent and cited algorithms with improved accuracy.


Assuntos
Pressão Sanguínea , Eletrocardiografia , Fotopletismografia/métodos , Algoritmos , Humanos
6.
J Res Med Sci ; 18(10): 860-4, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24497856

RESUMO

BACKGROUND: Diagnosis and treatment of neuropsychiatric lupus is still a major challenge in clinical practice. We investigated the association between depression and anti-ribosomal P (anti-P) antibodies in a sample of Iranian patients with systemic lupus erythematosus (SLE). MATERIALS AND METHODS: This cross-sectional study was conducted on adult patients with SLE referring to a referral out-patient clinic of rheumatology. Demographic data and clinical data with regards to measuring disease activity with the systemic lupus erythematosus disease activity index were gathered. Anti-P antibodies were measured with the enzyme-linked immunosorbent assay method. Depression severity was measured by the Beck Depression Inventory-II. RESULTS: One hundred patients (80% female and 20% male, age = 34.8 ± 10.9 years) were included. Anti-P antibodies were present more frequently in depressed than non-depressed patients (30% vs. 10%, P = 0.015). Depression severity was correlated with anti-P antibodies level only in patients with disease duration of less than 2 years (r = 0.517, P = 0.019). There was no association between the depression severity and disease activity. Binary logistic regression analysis showed age (B = 0.953, CI 95%: 0.914-0.993) and positive anti-P antibodies (B = 4.30, CI 95%: 1.18-15.59) as factors that independently associated with depression. CONCLUSION: We found an association between depression and presence of anti-P antibodies, and also strong correlation between depression severity and anti-P antibodies level in newly diagnosed SLE patients. Depression severity in newly diagnosed SLE patients may reflect a neuropsychiatric involvement, and in later phases, it is more affected by the chronicity of the disease as well as other environmental factors.

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