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1.
PLoS One ; 19(3): e0300650, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38527025

RESUMO

As the demand for high-bandwidth Internet connections continues to surge, industries are exploring innovative ways to harness this connectivity, and smart agriculture stands at the forefront of this evolution. In this paper, we delve into the challenges faced by Internet Service Providers (ISPs) in efficiently managing bandwidth and traffic within their networks. We propose a synergy between two pivotal technologies, Multi-Protocol Label Switching-Traffic Engineering (MPLS-TE) and Diffserv Quality of Service (Diffserv-QoS), which have implications beyond traditional networks and resonate strongly with the realm of smart agriculture. The increasing adoption of technology in agriculture relies heavily on real-time data, remote monitoring, and automated processes. This dynamic nature requires robust and reliable high-bandwidth connections to facilitate data flow between sensors, devices, and central management systems. By optimizing bandwidth utilization through MPLS-TE and implementing traffic control mechanisms with Diffserv-QoS, ISPs can create a resilient network foundation for smart agriculture applications. The integration of MPLS-TE and Diffserv-QoS has resulted in significant enhancements in throughput and a considerable reduction in Jitter. Employment of the IPv4 header has demonstrated impressive outcomes, achieving a throughput of 5.83 Mbps and reducing Jitter to 3 msec.


Assuntos
Algoritmos , Redes de Comunicação de Computadores , Simulação por Computador , Tecnologia sem Fio , Agricultura
2.
PLoS One ; 19(2): e0294235, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38354194

RESUMO

This paper introduces a method aiming at enhancing the efficacy of speaker identification systems within challenging acoustic environments characterized by noise and reverberation. The methodology encompasses the utilization of diverse feature extraction techniques, including Mel-Frequency Cepstral Coefficients (MFCCs) and discrete transforms, such as Discrete Cosine Transform (DCT), Discrete Sine Transform (DST), and Discrete Wavelet Transform (DWT). Additionally, an Artificial Neural Network (ANN) serves as the classifier for this method. Reverberation is modeled using varying-length comb filters, and its impact on pitch frequency estimation is explored via the Auto Correlation Function (ACF). This paper also contributes to the field of cancelable speaker identification in both open and reverberation environments. The proposed method depends on comb filtering at the feature level, deliberately distorting MFCCs. This distortion, incorporated within a cancelable framework, serves to obscure speaker identities, rendering the system resilient to potential intruders. Three systems are presented in this work; a reverberation-affected speaker identification system, a system depending on cancelable features through comb filtering, and a novel cancelable speaker identification system within reverbration environments. The findings revealed that, in both scenarios with and without reverberation effects, the DWT-based features exhibited superior performance within the speaker identification system. Conversely, within the cancelable speaker identification system, the DCT-based features represent the top-performing choice.


Assuntos
Redes Neurais de Computação , Ruído , Acústica , Análise de Ondaletas
3.
PLoS One ; 19(1): e0296999, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38206931

RESUMO

Filter Bank Multi-Carrier (FBMC) is attracting significant interest as a multi-carrier modulation (MCM) approach for future communication systems. It offers numerous advantages in contrast to Orthogonal Frequency Division Multiplexing (OFDM). Nonetheless, similar to many other MCM techniques, FBMC encounters a significant challenge with a high Peak-to-Average Power Ratio (PAPR). Additionally, incorporating Multiple-Input and Multiple-Output (MIMO) into FBMC presents heightened difficulties due to the presence of complex interference and increased computational complexity. In this paper, we first study the performance analysis of MIMO based Quadrature Amplitude Modulation (QAM)-FBMC systems considering the system complexity and interference. To enhance coverage effectively using beamforming with multiple antennas, it is essential to reduce PAPR to minimize the input backoff (IBO) required by nonlinear power amplifiers. Therefore, we propose new PAPR reduction method for MIMO based QAM-FBMC systems leveraging the null space within the MIMO channel using clipping and filtering (CF) technique. The PAPR reduction signals generated in this process are then mapped to the null space of the overall MIMO channel for each frequency block. Through computer simulations using a nonlinear power amplifier model, we illustrate that the proposed method substantially enhances both PAPR and throughput of MIMO based FBMC systems compared to conventional methods.


Assuntos
Amplificadores Eletrônicos , Entorses e Distensões , Humanos , Simulação por Computador
4.
Molecules ; 23(12)2018 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-30477238

RESUMO

A series of novel 1,3,4-triarylpyrazoles containing different heterocycles has been prepared, characterized and screened for their in vitro antiproliferative activity against HePG-2, MCF-7, PC-3, A-549 and HCT-116 cancer cell lines. The biological results revealed that compound 6 showed the highest anticancer activity so it was subjected to a kinase assay study where it reduced the activity of several protein kinases including AKT1, AKT2, BRAF V600E, EGFR, p38α and PDGFRß at 100 µM using the radiometric or ADP-Glo assay method. Molecular docking simulation supported the initial kinase assay and suggested a common mode of interaction at the ATP-binding sites of these kinases, which demonstrates that compound 6 is a potential agent for cancer therapy deserving further research.


Assuntos
Antineoplásicos/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteínas Quinases/química , Pirazóis/química , Antineoplásicos/farmacologia , Sítios de Ligação , Domínio Catalítico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Ligação de Hidrogênio , Concentração Inibidora 50 , Ligantes , Espectroscopia de Ressonância Magnética , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Relação Quantitativa Estrutura-Atividade
5.
J Sports Med Phys Fitness ; 56(10): 1206-1213, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26329839

RESUMO

BACKGROUND: This study aimed to investigate the effect of prolonged exercise with and without a thermal clamp on leukocyte cell, stress hormones, cytokine and muscle damage responses. METHODS: Fifteen healthy male volunteers (means±SD: age 22±3 yr; mass 75.8±3.2 kg; maximal oxygen uptake 55±7 mL/min/kg) randomly completed four chamber trials of 1 hour each, in different environment and separated by 7 days. Trials were: 1) exercise induced heating (EX-heating [EX-H]: temperature/humidity, 38° C/50%); 2) exercise with a thermal clamp (EX-cooling [EX-C]: temperature/humidity, 18° C/50%); 3) passive heating (PA-H: temperature/ humidity, 38° C/50%); 4) passive cooling (PA-C: temperature/ humidity, 18° C/50%). EX-H and EX-C were composed of 1h treadmill runs at 80% individual anaerobic threshold (IAT). Blood samples were collected at pre-post, and 1h postenvironments exposure. RESULTS: Compared to EX-H, exercise-induced increases in core temperature, heart rate, cortisol, human growth hormone (hGH)), Interleukin-6 (IL-6), leukocyte counts and creatine kinase (CK) and Myoglobin (Mb) were significantly (P<0.01) more pronounced than in EX-C. CONCLUSIONS: These results suggest that the additional impact of elevated ambient temperatures on stress responses to endurance exercise in trained subjects seems to affect primarily the hormonal systems and resulting changes in leukocyte number, creatine kinase, Myoglobin and interleukine-6.


Assuntos
Exercício Físico/fisiologia , Temperatura Alta/efeitos adversos , Fadiga Muscular/fisiologia , Resistência Física/fisiologia , Estresse Fisiológico/fisiologia , Adulto , Biomarcadores/sangue , Citocinas/sangue , Teste de Esforço , Voluntários Saudáveis , Humanos , Umidade/efeitos adversos , Contagem de Leucócitos , Masculino , Resistência Física/imunologia , Distribuição Aleatória , Estresse Fisiológico/imunologia , Adulto Jovem
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