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1.
Sensors (Basel) ; 21(18)2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34577273

RESUMO

Inter-carrier interference (ICI) in vehicle to vehicle (V2V) orthogonal frequency division multiplexing (OFDM) systems is a common problem that makes the process of detecting data a demanding task. Mitigation of the ICI in V2V systems has been addressed with linear and non-linear iterative receivers in the past; however, the former requires a high number of iterations to achieve good performance, while the latter does not exploit the channel's frequency diversity. In this paper, a transmission and reception scheme for low complexity data detection in doubly selective highly time varying channels is proposed. The technique couples the discrete Fourier transform spreading with non-linear detection in order to collect the available channel frequency diversity and successfully achieving performance close to the optimal maximum likelihood (ML) detector. When compared with the iterative LMMSE detection, the proposed system achieves a higher performance in terms of bit error rate (BER), reducing the computational cost by a third-part when using 48 subcarriers, while in an OFDM system with 512 subcarriers, the computational cost is reduced by two orders of magnitude.

2.
Micromachines (Basel) ; 12(2)2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33673049

RESUMO

Current computing platforms encourage the integration of thousands of processing cores, and their interconnections, into a single chip. Mobile smartphones, IoT, embedded devices, desktops, and data centers use Many-Core Systems-on-Chip (SoCs) to exploit their compute power and parallelism to meet the dynamic workload requirements. Networks-on-Chip (NoCs) lead to scalable connectivity for diverse applications with distinct traffic patterns and data dependencies. However, when the system executes various applications in traditional NoCs-optimized and fixed at synthesis time-the interconnection nonconformity with the different applications' requirements generates limitations in the performance. In the literature, NoC designs embraced the Software-Defined Networking (SDN) strategy to evolve into an adaptable interconnection solution for future chips. However, the works surveyed implement a partial Software-Defined Network-on-Chip (SDNoC) approach, leaving aside the SDN layered architecture that brings interoperability in conventional networking. This paper explores the SDNoC literature and classifies it regarding the desired SDN features that each work presents. Then, we described the challenges and opportunities detected from the literature survey. Moreover, we explain the motivation for an SDNoC approach, and we expose both SDN and SDNoC concepts and architectures. We observe that works in the literature employed an uncomplete layered SDNoC approach. This fact creates various fertile areas in the SDNoC architecture where researchers may contribute to Many-Core SoCs designs.

3.
Gac. méd. Méx ; 156(6): 569-579, nov.-dic. 2020. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1249969

RESUMO

Resumen Introducción: México tiene la mortalidad más alta a 30 días por infarto agudo de miocardio (IAM), el cual constituye una de las principales causas de mortalidad en el país: 28 % versus 7.5 % del promedio de los países de la Organización para la Cooperación y el Desarrollo Económicos. Objetivo: Establecer las rutas críticas y las estrategias farmacológicas esenciales interinstitucionales para la atención de los pacientes con IAM en México, independientemente de su condición socioeconómica. Método: Se reunió a un grupo de expertos en diagnóstico y tratamiento de IAM, representantes de las principales instituciones públicas de salud de México, así como las sociedades cardiológicas mexicanas, Cruz Roja Mexicana y representantes de la Sociedad Española de Cardiología, con la finalidad de optimizar las estrategias con base en la mejor evidencia existente. Resultados: Se diseñó una guía de práctica clínica interinstitucional para el diagnóstico temprano y tratamiento oportuno del IAM con elevación del segmento ST, siguiendo el horizonte clínico de la enfermedad, con la propuesta de algoritmos que mejoren el pronóstico de los pacientes que acuden por IAM a los servicios de urgencias. Conclusión: Con la presente guía práctica, el grupo de expertos propone universalizar el diagnóstico y tratamiento en el IAM, independientemente de la condición socioeconómica del paciente.


Abstract Introduction: Mexico has the highest 30-day acute myocardial infarction (AMI) mortality rate: 28% versus 7.5% on average for the OECD countries, and it constitutes one of the main causes of mortality in the country. Objective: To establish critical pathways and essential interinstitutional pharmacological strategies for the care of patients with AMI in Mexico, regardless of their socioeconomic status. Method: A group of experts in AMI diagnosis and treatment, representatives of the main public health institutions in Mexico, as well as the Mexican cardiology societies, the Mexican Red Cross and representatives of the Spanish Society of Cardiology, were brought together in order to optimize strategies based on the best existing evidence. Results: An interinstitutional clinical practice guideline was designed for early diagnosis and timely treatment of AMI with ST elevation, following the clinical horizon of the disease, with the proposal of algorithms that improve the prognosis of patients who attend the emergency services due to an AMI. Conclusion: With these clinical practice guidelines, the group of experts proposes to universalize AMI diagnosis and treatment, regardless of patient socioeconomic status.


Assuntos
Humanos , Consenso , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Sociedades Médicas , Espanha , Biomarcadores/sangue , Reperfusão Miocárdica/métodos , Terapia Trombolítica/métodos , Causas de Morte , Eletrocardiografia , Intervenção Coronária Percutânea/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/reabilitação , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Reabilitação Cardíaca , COVID-19/prevenção & controle , México
4.
Gac Med Mex ; 156(6): 559-569, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33877123

RESUMO

INTRODUCTION: Mexico has the highest 30-day mortality due to acute myocardial infarction (AMI), which constitutes one of the main causes of mortality in the country: 28 % versus 7.5 % on average for the Organization for Economic Co-operation and Development member countries. OBJECTIVE: To establish critical pathways and essential interinstitutional pharmacological strategies for the care of patients with AMI in Mexico, regardless of their socioeconomic status. METHOD: A group of experts in AMI diagnosis and treatment, representatives of the main public health institutions in Mexico, as well as the Mexican cardiology societies, the Mexican Red Cross and representatives of the Spanish Society of Cardiology, were brought together in order to optimize strategies based on the best existing evidence. RESULTS: An interinstitutional clinical practice guideline was designed for early diagnosis and timely treatment of AMI with ST-segment elevation, following the clinical horizon of the disease, with the proposal of algorithms that improve the prognosis of patients who attend the emergency services due to an AMI. CONCLUSION: With these clinical practice guidelines, the group of experts proposes to universalize AMI diagnosis and treatment, regardless of patient socioeconomic status. INTRODUCCIÓN: México tiene la mortalidad más alta a 30 días por infarto agudo de miocardio (IAM), el cual constituye una de las principales causas de mortalidad en el país: 28 % versus 7.5 % del promedio de los países de la Organización para la Cooperación y el Desarrollo Económicos. OBJETIVO: Establecer las rutas críticas y las estrategias farmacológicas esenciales interinstitucionales para la atención de los pacientes con IAM en México, independientemente de su condición socioeconómica. MÉTODO: Se reunió a un grupo de expertos en diagnóstico y tratamiento de IAM, representantes de las principales instituciones públicas de salud de México, así como las sociedades cardiológicas mexicanas, Cruz Roja Mexicana y representantes de la Sociedad Española de Cardiología con la finalidad de optimizar las estrategias con base en la mejor evidencia existente. RESULTADOS: Se diseñó una guía de práctica clínica interinstitucional para el diagnóstico temprano y tratamiento oportuno del IAM con elevación del segmento ST, siguiendo el horizonte clínico de la enfermedad, con la propuesta de algoritmos que mejoren el pronóstico de los pacientes que acuden por IAM a los servicios de urgencias. CONCLUSIÓN: Con la presente guía práctica, el grupo de expertos propone universalizar el diagnóstico y tratamiento en el IAM, independientemente de la condición socioeconómica del paciente.


Assuntos
Consenso , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Biomarcadores/sangue , COVID-19/prevenção & controle , Reabilitação Cardíaca , Causas de Morte , Eletrocardiografia , Humanos , México , Reperfusão Miocárdica/métodos , Intervenção Coronária Percutânea/métodos , Infarto do Miocárdio com Supradesnível do Segmento ST/sangue , Infarto do Miocárdio com Supradesnível do Segmento ST/reabilitação , Sociedades Médicas , Espanha , Terapia Trombolítica/métodos
5.
Front Med (Lausanne) ; 6: 210, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31612137

RESUMO

Peritoneal dialysis (PD) is an alternative for managing the end-stage renal disease (ESRD). The peritoneal membrane (PM) is not just a membrane that passively responds to diffusion and convection. The characteristics of PM result in the peritoneal equilibrium test (PET) and with this test is possible to obtain the type of peritoneal transport (PT). The patient on PD can be classified in different types of PT as; Low, Low Average, High Average, and High. The aim of the study was to compare the inflammatory cytokines, oxidants, antioxidants, and oxidative DNA damage markers in the different types of PT. A cross-sectional analytical study of 77 adult PD patients was performed. Levels of lipoperoxides (LPO) were higher in all types of PT vs. healthy volunteer controls (HC) (p < 0.0001). Nitric oxide (NO) levels were found significantly down-regulated in all types of PT (p < 0.0001). The activity of the superoxide dismutase enzyme (SOD) was found to be significantly increased in all types of PT vs. the HC (p < 0.0001). The levels of the DNA repair enzyme were found to be decreased in all types of PT. The levels of the pro-inflammatory cytokines TNF-α, IL-6, the marker of oxidative DNA damage, 8-IP and the total antioxidant capacity (TAC) were all significantly decreased, contrary to the levels in HC, possibly by the clearance in the dialysis fluid in all types of PT or due to down-regulation of their expression. In conclusion, we found significant changes in markers of inflammation, oxidative stress, and oxidative damage to DNA in all types of PT; Low, low average, high average, and high PT in the values of D/P creatinine at 4 h compared to HC.

6.
Gac Med Mex ; 155(3): 229-235, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31219459

RESUMO

INTRODUCTION: Multi-frequency bio-impedance analysis (BIA) accurately evaluates body composition. OBJECTIVE: To assess nutritional status and its relationship with body mass index (BMI) or with BIA-obtained phase angle in patients with end-stage renal disease (ESRD) on hemodialysis. METHOD: BMI, BIA and dialysis malnutrition score (DMS) were assessed in 99 patients on hemodialysis (43.6 ± 17.2 years of age, 58.8% males). Multivariate linear regression analysis was used to determine BMI and phase angle independent associations with DMS. RESULTS: Malnutrition risk (DMS > 13) showed a gradual increase among patients with normal BMI and phase angle (44.4%), low BMI (45.8%), low phase angle (64.0%), and in those with both parameters at abnormal ranges (68.0%). The phase angle was the only variable that was independently associated with patient nutritional status (standardized coefficient beta -0.372, p < 0.001), accounting for 13.8% of DMS variation. CONCLUSION: Phase angle is inversely and independently associated with malnutrition risk in patients with ESRD, which suggests that BIA-assessed body composition might be better than BMI in the clinical assessment of patients with ESRD.


INTRODUCCIÓN: La bioimpedancia eléctrica multifrecuencia (BIE) evalúa con precisión la composición corporal. OBJETIVO: Investigar el estado nutricional y su relación con el índice de masa corporal (IMC) o el ángulo fase obtenido por BIE en pacientes con enfermedad renal terminal (ERT) en hemodiálisis. MÉTODO: En 99 pacientes en hemodiálisis (43.6 ± 17.2 años, 58.8 % varones) se evaluó IMC, BIE y puntuación de desnutrición (DMS, Dialysis Malnutrition Score). La independencia de las asociaciones del IMC y el ángulo fase con el DMS se determinó con regresión lineal múltiple. RESULTADOS: El riesgo de desnutrición (DMS > 13) se incrementó gradualmente entre los sujetos con IMC y ángulo fase normales (44.4 %), IMC bajo (45.8 %), ángulo fase bajo (64.0 %) y en aquellos con ambos parámetros anormales (68.0 %). El ángulo fase fue la única variable asociada independientemente con el estado nutricional de los pacientes (coeficiente beta estandarizado −0.372, p < 0.001), lo que explicó 13.8 % de la variación en el DMS. CONCLUSIONES: El ángulo fase se asocia inversa e independientemente con el riesgo de desnutrición en pacientes con ERT, lo que sugiere que la composición corporal evaluada por BIE pudiera ser mejor que el IMC en la valoración clínica de pacientes con esta enfermedad.


Assuntos
Impedância Elétrica , Falência Renal Crônica/terapia , Desnutrição/epidemiologia , Diálise Renal/métodos , Adulto , Idoso , Composição Corporal , Índice de Massa Corporal , Estudos Transversais , Feminino , Humanos , Masculino , Desnutrição/diagnóstico , Desnutrição/etiologia , Pessoa de Meia-Idade , Estado Nutricional , Adulto Jovem
7.
Gac. méd. Méx ; 155(3): 229-235, may.-jun. 2019. tab, graf
Artigo em Inglês, Espanhol | LILACS | ID: biblio-1286496

RESUMO

Resumen Introducción: La bioimpedancia eléctrica multifrecuencia (BIE) evalúa con precisión la composición corporal. Objetivo: Investigar el estado nutricional y su relación con el índice de masa corporal (IMC) o el ángulo fase obtenido por BIE en pacientes con enfermedad renal terminal (ERT) en hemodiálisis. Método: En 99 pacientes en hemodiálisis (43.6 ± 17.2 años, 58.8 % varones) se evaluó IMC, BIE y puntuación de desnutrición (DMS, Dialysis Malnutrition Score). La independencia de las asociaciones del IMC y el ángulo fase con el DMS se determinó con regresión lineal múltiple. Resultados: El riesgo de desnutrición (DMS > 13) se incrementó gradualmente entre los sujetos con IMC y ángulo fase normales (44.4 %), IMC bajo (45.8 %), ángulo fase bajo (64.0 %) y en aquellos con ambos parámetros anormales (68.0 %). El ángulo fase fue la única variable asociada independientemente con el estado nutricional de los pacientes (coeficiente beta estandarizado −0.372, p < 0.001), lo que explicó 13.8 % de la variación en el DMS. Conclusiones: El ángulo fase se asocia inversa e independientemente con el riesgo de desnutrición en pacientes con ERT, lo que sugiere que la composición corporal evaluada por BIE pudiera ser mejor que el IMC en la valoración clínica de pacientes con esta enfermedad.


Abstract Introduction: Multi-frequency bio-impedance analysis (BIA) accurately evaluates body composition. Objective: To assess nutritional status and its relationship with body mass index (BMI) or with BIA-obtained phase angle in patients with end-stage renal disease (ESRD) on hemodialysis. Method: BMI, BIA and dialysis malnutrition score (DMS) were assessed in 99 patients on hemodialysis (43.6 ± 17.2 years of age, 58.8% males). Multivariate linear regression analysis was used to determine BMI and phase angle independent associations with DMS. Results: Malnutrition risk (DMS > 13) showed a gradual increase among patients with normal BMI and phase angle (44.4%), low BMI (45.8%), low phase angle (64.0%), and in those with both parameters at abnormal ranges (68.0%). The phase angle was the only variable that was independently associated with patient nutritional status (standardized coefficient beta −0.372, p < 0.001), accounting for 13.8% of DMS variation. Conclusion: Phase angle is inversely and independently associated with malnutrition risk in patients with ESRD, which suggests that BIA-assessed body composition might be better than BMI in the clinical assessment of patients with ESRD.


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Adulto Jovem , Diálise Renal/métodos , Impedância Elétrica , Desnutrição/epidemiologia , Falência Renal Crônica/terapia , Composição Corporal , Índice de Massa Corporal , Estado Nutricional , Estudos Transversais , Desnutrição/diagnóstico , Desnutrição/etiologia
8.
Sensors (Basel) ; 19(9)2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31064133

RESUMO

With the rapid deployment of the Internet of Things and cloud computing, it is necessary to enhance authentication protocols to reduce attacks and security vulnerabilities which affect the correct performance of applications. In 2019 a new lightweight IoT-based authentication scheme in cloud computing circumstances was proposed. According to the authors, their protocol is secure and resists very well-known attacks. However, when we evaluated the protocol we found some security vulnerabilities and drawbacks, making the scheme insecure. Therefore, we propose a new version considering login, mutual authentication and key agreement phases to enhance the security. Moreover, we include a sub-phase called evidence of connection attempt which provides proof about the participation of the user and the server. The new scheme achieves the security requirements and resists very well-known attacks, improving previous works. In addition, the performance evaluation demonstrates that the new scheme requires less communication-cost than previous authentication protocols during the registration and login phases.

9.
J Matern Fetal Neonatal Med ; 32(4): 542-549, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28988522

RESUMO

OBJECTIVE: The number of successful pregnancies in kidney transplant (KT) recipients has increased in recent years. Little evidence is available about the risk of in utero immunosuppressive exposure for long-term cognitive consequences. The aim of this study was to evaluate the impact of immunosuppression during pregnancy on intellectual performance of children born to KT recipients. METHODS: Using a cross-sectional design, women who had undergone KT and their children (aged 4+ years) were recruited at the outpatient follow-up in five transplant centers. Women who did not receive immunosuppression during pregnancy with similar distributions of socioeconomic status and length of gestation and their children were also recruited. Children were assessed with Wechsler Intelligence Scales. RESULTS: The study sample included 50 exposed and 50 unexposed children. No differences between groups in all the proposed confounding factors were found. Full-scale IQ did not differ significantly between both groups. Also, significant differences in any index or subscale score were not observed, with the exception of time required to complete the Wechsler preschool and primary scale of intelligence (WPPSI) Zoo locations subtest, which was done quicker in the unexposed group (p = .007). Exposure to immunosuppression during pregnancy was not a significant predictor of low IQ in logistic regression after adjustment for other factors. CONCLUSIONS: Immunosuppression therapy during pregnancy of KT women did not affect global intellectual performance of their offspring, except maybe for visuospatial working memory in preschool children.


Assuntos
Imunossupressores/efeitos adversos , Inteligência/efeitos dos fármacos , Rim , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Transplantados , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Transplante de Rim , Modelos Logísticos , Masculino , Memória de Curto Prazo/efeitos dos fármacos , Pessoa de Meia-Idade , Gravidez , Escalas de Wechsler
10.
J Clin Lab Anal ; 33(2): e22691, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30345559

RESUMO

INTRODUCTION: Diabetic Nephropathy (DN) is the main cause of chronic kidney disease (CKD) in diabetic patients. An IL-10 imbalance could be related to renal hypertrophy and trigger to nephropathy. Three promoter polymorphisms (-1082G>A, -819C>T, and -592C>A) at IL10 gene have been associated with changes in the IL-10 expression and DN susceptibility. Therefore, the aim of this study was to analyze this association in Mexican patients with DN. METHODS: We conducted a case-control study on 128 patients with DN and 150 control subjects (CS) from western Mexico. All patients were tested for IL10 polymorphisms by PCR-RFLP. Allele frequencies, genotypes, and haplotypes were compared between groups. The significant haplotypes were correlated with patient clinical features. RESULTS: IL10 gene ATC haplotype (-1082A/-819T/-592C) was found significantly more frequent in DN patients than in CS (P < 0.001; OR = 3.6, 95% CI: 1.7-7.4). Similarly GTA (-1082G/-819T/-592A) haplotype was more frequent in DN patients than CS with significant differences (P < 0.05; OR = 4.02, 95% CI: 1.10-14.78). There were no correlations between IL10 haplotypes and clinical parameters in patients with DN. However, that there is a trend of higher serum urea levels and lower eGFR in ATC haplotype carriers compared to carriers of the other haplotypes (P < 0.05). CONCLUSIONS: These results indicate that IL10 promoter haplotypes ATC and GTA carriers have a higher risk factor to develop DN in the western Mexican population.


Assuntos
Nefropatias Diabéticas/epidemiologia , Nefropatias Diabéticas/genética , Predisposição Genética para Doença/epidemiologia , Predisposição Genética para Doença/genética , Interleucina-10/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Haplótipos/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
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