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1.
J Environ Manage ; 354: 120392, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38387355

RESUMO

The Paris Agreement, a landmark international treaty signed in 2016 to limit global warming to 2°C, has urged researchers to explore various strategies for achieving its ambitious goals. While Renewable Energy (RE) innovation holds promise, it alone may not be sufficient as critical deadlines approach. This field of research presents numerous challenges, foremost among them being the costliness of materials involved. However, emerging advancements in Machine Learning (ML) technologies provide a glimmer of hope; these sophisticated algorithms can accurately predict the output of energy systems without relying on physical resources and instead leverage available data from diverse energy platforms that have emerged over recent decades. The primary objective of this paper is to comprehensively explore various ML techniques and algorithms in the context of Renewable Energy Systems (RES). The investigation will address several vital inquiries, including identifying and evaluating existing RE technologies, assessing their potential for further advancement, and thoroughly analyzing the challenges and limitations associated with their deployment and testing. Furthermore, this research examines how ML can effectively overcome these obstacles by enhancing RES performance. By identifying future research opportunities and outlining potential directions for improvement, this work seeks to contribute to developing environmentally sustainable energy systems.


Assuntos
Algoritmos , Aquecimento Global , Aprendizado de Máquina , Paris , Energia Renovável
2.
Microsc Microanal ; 29(3): 1244-1257, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37749691

RESUMO

Polycystic ovary syndrome (PCOS) is one of the most common endocrine and reproductive disorders throughout female reproductive age. Cell free therapy [conditioned media (CM) & exosomes (EXO)] is a promising approach in regenerative medicine. This study aimed to compare between the therapeutic effects of stem cell-derived CM and exosomes on induced animal model of polycystic ovary. Polycystic ovary (PCO) was induced in female rats (3-4 weeks old, weighing 70-80 g) by letrozole with a dose of 1 mg/kg/day dissolved in carboxymethylcellulose 1% orally once daily for 5 weeks. Animals were divided into four groups: control group, PCO group, EXO-treated group, and CM-treated group. Serum levels of testosterone hormone, leutinizing hormone, follicle stimulatimg hormone, and insulin hormone were estimated. Immunohistochemistry using anti-P53, anti-AMP-dependent protein kinase antibodies were done. Six rats/group were used for matting with adult male rats for testing fertility. The results showed that CM had significant superior therapeutic effects on exosomes in restoring the normal histological architecture of the ovary and fertility. In summary, cell free treatment is a safe approach for tissue regeneration. Stem cell-derived CM was more effective than exosomes in restoring normal histological structure of the ovaries and fertility in animal models of polycystic ovary.


Assuntos
Exossomos , Síndrome do Ovário Policístico , Feminino , Masculino , Animais , Ratos , Humanos , Síndrome do Ovário Policístico/tratamento farmacológico , Meios de Cultivo Condicionados , Células-Tronco , Hormônios
3.
Int J Inf Secur ; 21(1): 115-158, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33776611

RESUMO

The recent digital revolution led robots to become integrated more than ever into different domains such as agricultural, medical, industrial, military, police (law enforcement), and logistics. Robots are devoted to serve, facilitate, and enhance the human life. However, many incidents have been occurring, leading to serious injuries and devastating impacts such as the unnecessary loss of human lives. Unintended accidents will always take place, but the ones caused by malicious attacks represent a very challenging issue. This includes maliciously hijacking and controlling robots and causing serious economic and financial losses. This paper reviews the main security vulnerabilities, threats, risks, and their impacts, and the main security attacks within the robotics domain. In this context, different approaches and recommendations are presented in order to enhance and improve the security level of robotic systems such as multi-factor device/user authentication schemes, in addition to multi-factor cryptographic algorithms. We also review the recently presented security solutions for robotic systems.

4.
Microprocess Microsyst ; 77: 103201, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32834204

RESUMO

Typically, Cyber-Physical Systems (CPS) involve various interconnected systems, which can monitor and manipulate real objects and processes. They are closely related to Internet of Things (IoT) systems, except that CPS focuses on the interaction between physical, networking and computation processes. Their integration with IoT led to a new CPS aspect, the Internet of Cyber-Physical Things (IoCPT). The fast and significant evolution of CPS affects various aspects in people's way of life and enables a wider range of services and applications including e-Health, smart homes, e-Commerce, etc. However, interconnecting the cyber and physical worlds gives rise to new dangerous security challenges. Consequently, CPS security has attracted the attention of both researchers and industries. This paper surveys the main aspects of CPS and the corresponding applications, technologies, and standards. Moreover, CPS security vulnerabilities, threats and attacks are reviewed, while the key issues and challenges are identified. Additionally, the existing security measures are presented and analyzed while identifying their main limitations. Finally, several suggestions and recommendations are proposed benefiting from the lessons learned throughout this comprehensive review.

5.
Internet Things (Amst) ; 11: 100218, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38620271

RESUMO

Recently, the world witnessed a significant increase in the number of used drones, with a global and continuous rise in the demand for their multi-purpose applications. The pervasive aspect of these drones is due to their ability to answer people's needs. Drones are providing users with a bird's eye that can be activated and used almost anywhere and at any time. However, recently, the malicious use of drones began to emerge among criminals and cyber-criminals alike. The probability and frequency of these attacks are both high and their impact can be very dangerous with devastating effects. Therefore, the need for detective, protective and preventive counter-measures is highly required. The aim of this survey is to investigate the emerging threats of using drones in cyber-attacks, along the countermeasures to thwart these attacks. The different uses of drones for malicious purposes are also reviewed, along the possible detection methods. As such, this paper analyzes the exploitation of drones vulnerabilities within communication links, as well as smart devices and hardware, including smart-phones and tablets. Moreover, this paper presents a detailed review on the drone/Unmanned Aerial Vehicle (UAV) usage in multiple domains (i.e civilian, military, terrorism, etc.) and for different purposes. A realistic attack scenario is also presented, which details how the authors performed a simulated attack on a given drone following the hacking cycle. This review would greatly help ethical hackers to understand the existing vulnerabilities of UAVs in both military and civilian domains. Moreover, it allows them to adopt and come up with new techniques and technologies for enhanced UAV attack detection and protection. As a result, various civilian and military anti-drones/UAVs (detective and preventive) countermeasures will be reviewed.

6.
Drug Dev Ind Pharm ; 45(2): 231-243, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30260710

RESUMO

OBJECTIVE: Oral gastroretentive system is one of the site-specific drug delivery system, which is designed to be retained in upper GIT for a prolonged time. Ranitidine hydrochloride (RHCl), which is used frequently in treatment of peptic ulcer, is a suitable candidate for gastroretentive delivery systems. Dependently, floating oil-entrapped alginate beads of RHCl were developed and evaluated as an approach to site-specific delivery avoiding colonic degradation and enhancing both bioavailability and the proposed local effect. METHODS: Different formulations of floating beads were suggested and randomized using 24 full factorial design. Optimized formulation was subjected for in vivo studies to measure the oral bioavailability and the healing effect of induced peptic ulcers. RESULTS: Beads size ranged from 1.32 to 2.3 mm. All beads revealed excellent floating capabilities. Optimum formulation (F12) has entrapment efficiency of 70%, drug loading of 7% and 71% RHCl released after 6 h. SEM of F12 shows a grossly spherical structure with presence of oil droplets distributed throughout structure. AUC obtained from F12 was nonsignificantly higher than that of a commercial tablet. Signs of ulcer healing appeared clearly with F12 through appearance of granulation tissue, collagen fibers and newly formed blood vessels. Healing rate and extent obtained with a commercial tablet were less than F12. Quantitative analysis confirmed histopathological findings. CONCLUSION: Floating oil-entrapped beads are a promising approach for RHCl delivery to remain in stomach for a longer time ensuring site-specific delivery and consequently, enhancing local healing effect of peptic ulcers.


Assuntos
Antiulcerosos/administração & dosagem , Antiulcerosos/uso terapêutico , Óleos/química , Úlcera Péptica/tratamento farmacológico , Ranitidina/administração & dosagem , Ranitidina/uso terapêutico , Animais , Antiulcerosos/farmacocinética , Disponibilidade Biológica , Colágeno/metabolismo , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Excipientes/química , Tecido de Granulação/patologia , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Tamanho da Partícula , Úlcera Péptica/patologia , Coelhos , Ranitidina/farmacocinética
7.
Acta Pharm ; 62(1): 59-70, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22472449

RESUMO

The purpose of this study was to develop pluronic-based in situ gelling formulations of metronidazole (MTZ) for treatment of bacterial vaginosis, aimed at prolonging the residence time, controlling drug release, enhancing efficacy, decreasing recurrence, and increasing patient compliance. The in situ gel formulations were prepared using different concentrations of pluronic F-127 (PF-127) alone and in combination with pluronic F-68 (PF-68). The prepared formulations were evaluated for their gelation temperature (T(gel)), in vitro drug release, rheological properties, mucoadhesion properties and tolerability by vaginal mucosa in tissue levels. The T(gel) decreased with increasing PF-127 concentration. The T(gel) was modulated by addition of PF-68 to be within the acceptable range of 25-37 °C. With increasing pluronic concentration, the in vitro drug release decreased, viscosity and mucoadhesive force increased. Histopathological examination of rabbit vaginas from the control and treated groups revealed normal histology of the vagina and cervix. Based on the in vitro evaluation of prepared formulations, the in situ gelling liquid formulated with PF-127/PF-68 (20/10 %, m/m) was selected for further clinical evaluation.


Assuntos
Anti-Infecciosos/química , Portadores de Fármacos , Metronidazol/química , Poloxâmero/química , Temperatura , Adesividade , Administração Intravaginal , Animais , Anti-Infecciosos/administração & dosagem , Anti-Infecciosos/metabolismo , Química Farmacêutica , Preparações de Ação Retardada , Composição de Medicamentos , Feminino , Géis , Cinética , Metronidazol/administração & dosagem , Metronidazol/metabolismo , Mucosa/metabolismo , Coelhos , Reologia , Solubilidade , Tecnologia Farmacêutica/métodos , Vaginose Bacteriana/tratamento farmacológico , Viscosidade
8.
ISA Trans ; 41(3): 365-82, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12160349

RESUMO

This paper investigates the application of a fault diagnosis and accommodation method to a real system composed of three tanks. The performance of a closed-loop system can be altered by the occurrence of faults which can, in some circumstances, cause serious damage on the system. The research goal is to prevent the system deterioration by developing a controller that has some capabilities to compensate for faults, that is, the fault accommodation or fault-tolerant control. In this paper, a two-step scheme composed of a fault detection, isolation and estimation module, and a control compensation module is presented. The main contribution is to develop a unique structured residual generator able to isolate and estimate both sensor and actuator faults. This estimation is of paramount importance to compensate for these faults and to preserve the system performances. The application of this method to the three-tank system gives encouraging results which are presented and commented on in case of various kinds of faults.


Assuntos
Análise de Falha de Equipamento/métodos , Retroalimentação , Modelos Teóricos , Dinâmica não Linear , Desenho de Equipamento , Controle de Qualidade , Sensibilidade e Especificidade , Transdutores
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