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Advanced Paternal Age and Sperm DNA Fragmentation: A Systematic Review
Gonzalez Daniel C.,Ory Jesse,Blachman-Braun Ruben,Nackeeran Sirpi,Best Jordan C.,Ramasamy Ranjith 대한남성과학회 2022 The World Journal of Men's Health Vol.40 No.1
Purpose: Male ageing is often associated with defective sperm DNA remodeling mechanisms that result in poorly packaged chromatin and a decreased ability to repair DNA strand breaks. However, the impact of advanced paternal age on DNA fragmentation remains inconclusive. The aim of the present systematic review was to investigate the impact of advancing paternal age (APA) on DNA fragmentation. Materials and Methods: We conducted a thorough search of listed publications in Scopus, PubMed, and EMBASE, in accordance with the PRISMA guidelines. Results: We identified 3,120 articles, of which nineteen were selected for qualitative analysis, resulting in a sample of 40,668 men. Of the 19 articles evaluating the impact of APA on DFI% (DNA fragmentation Index) included, 4 were on Normozoospermic and subfertile men, 3 on normozoospermic, Oligoasthenoteratozoospermic and Teratozoospermic, 6 on fertile and infertile men, 4 on just infertile men, and 2 evaluated a general population. Seventeen of the ninrnteen studies demonstrated APA’s effect and impact on DFI%. Conclusions: Although there was no universal definition for APA, the present review suggests that older age is associated with increased DFI. In elderly men with normal semen parameters, further studies should be performed to assess the clinical implications of DFI, as a conventional semen analysis can often fail to detect an etiology for infertility.
Sarcopenia in hemodialysis patients from Buenos Aires, Argentina
Ruben Abdala,Elisa Elena del Valle,Armando Luis Negri,Pablo Bridoux,Luciana Gonzalez Paganti,Marina Bravo,Luis Sintado,Paula Di Rienzo,Omar R. Schiavelli,Maria Belén Zanchetta,Adrián Guinsburg 대한골다공증학회 2021 Osteoporosis and Sarcopenia Vol.7 No.2
Objectives: Sarcopenia is the loss of skeletal muscle mass and function that occurs with aging that can lead to greater morbidity and mortality. Chronic kidney disease and hemodialysis (HD) favors the development of sarcopenia.We studied the prevalence of sarcopenia and its components using European Working Group on Sarcopenia in Elderly People 2 proposed criteria and risk factors for its development in HD patients. Methods: In 100 adult HD patients, we evaluated: hand grip strength (HGS), muscle mass by dual energy X-ray absorptiometry and physical performance (gait-speed and sit-stand test). Results: Sixty patients were male and 40 were female; mean age 55.6 years. Prevalence of sarcopenia was 16% (11.1% in males and 25% in females; P = 0.05); 7% had severe sarcopenia. Prevalence of low HGS was 33% in males and 28% in females; low muscle mass was 30% in males but 70% in females and low physical performance 23% in males and 45% in females. Falls were reported by 23 patients. Patients with lower HGS had a higher prevalence of falls in the last year (40% two or more falls; P = 0.03). Only females with sarcopenia had lower bone mineral content. Neither age, body mass index, time on dialysis, or prevalence of diabetes predicted sarcopenia. Conclusions: A significant proportion of dialysis patients had sarcopenia, more frequent in females. Low HGS was associated with a higher prevalence of falls. Only females with sarcopenia had lower bone mineral content.
Generalized Quadrature Spatial Modulation Scheme Using Antenna Grouping
Francisco Ruben Castillo-Soria,Joaquın Cortez-Gonzalez,Raymundo Ramirez-Gutierrez,Fermın Marcelo Maciel-Barboza,Leonel Soriano-Equigua 한국전자통신연구원 2017 ETRI Journal Vol.39 No.5
This paper presents a novel generalized quadrature spatial modulation (GQSM) transmission scheme using antenna grouping. The proposed GQSM scheme combines QSM and conventional spatial multiplexing (SMux) techniques in order to improve the spectral efficiency (SE) of the system. Analytical and simulation results show that the proposed transmission scheme has minimal losses in terms of the average bit error probability along with the advantage of an increased SE compared with previous SM and QSM schemes. For the case studies, this advantage represents a reduction of up to 81% in terms of the number of required transmit antennas compared with QSM. In addition, a detection architecture based on the ordered successive interference cancellation scheme and the QR decomposition is presented. The proposed QRD-M adaptive algorithm showed a near-maximum-likelihood performance with a complexity reduction of approximately 90%.
Jorge A. Gonzalez-y-Merchand,Ruben Zaragoza-Contreras,Rosalina Guadarrama-Medina,Addy C. Helguera-Repetto,Sandra Rivera-Gutierrez,Jorge F. Cerna-Cortes,Leopoldo Santos-Argumedo,Robert A. Cox 한국미생물학회 2012 The journal of microbiology Vol.50 No.3
The study of the in vitro cell growth of mycobacteria still remains a fastidious, difficult, and time-consuming procedure. In addition, assessing mycobacterial growth in the laboratory is often complicated by cell aggregation and slow growth-rate. We now report that the use of a stainless steel spring in the culture led to an absence of large cell clumps, to a decrease of dead cells in the exponential phase and to growth of a more homogeneous population of large cells. We also report that flow cytometry is a rapid, simple and reliable approach to monitor mycobacterial cell growth and viability. Here, we monitored Mycobacterium smegmatis cellular growth by optical density, dry cell mass, and colony forming units; in addition, viability, cell size and granularity profiles were analyzed by flow cytometry, and cell morphology by electron microscopy. Cultures monitored by flow cytometry may lead to a better understanding of the physiology of mycobacteria. Moreover, this methodology may aid in characterizing the cell growth of other fastidious species of microorganisms.
On the Design of a WiFi Direct 802.11ac WLAN under a TGn MIMO Multipath Fading Channel
( Gul Zameen Khan ),( Ruben Gonzalez ),( Eun-chan Park ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.3
WiFi Direct (WD) is a state of the art technology for a Device-to-Device (D2D) communication in 802.11 networks. The performance of the WD system can be significantly affected by some key factors such as the type of application, specifications of MAC and PHY layer parameters, and surrounding environment etc. It is, therefore, important to develop a system model that takes these factors into account. In this paper, we focus on investigating the design parameters of the PHY layer that could maximize the efficiency of the WD 802.11 system. For this purpose, a basic theoretical model is formulated for a WD network under a 2x2 Multiple In Multiple Out (MIMO) TGn channel B model. The design level parameters such as input symbol rate and antenna spacing, as well as the effects of the environment, are thoroughly examined in terms of path gain, spectral density, outage probability and Packet Error Rate (PER). Thereafter, a novel adaptive algorithm is proposed to choose optimal parameters in accordance with the Quality of Experience (QoE) for a targeted application. The simulation results show that the proposed method outperforms the standard method thereby achieving an optimal performance in an adaptive manner.
Extended PI Feedback Tracking Control for Synchronous Motors
Francisco Beltran-Carbajal,Ruben Tapia-Olvera,Irvin Lopez-Garcia,Antonio Valderrabano-Gonzalez,Julio Cesar Rosas-Caro,Jose Luis Hernandez-Avila 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.6
A new dynamic feedback tracking control method of desired velocity and current profiles for permanent magnet synchronous motors, without the additional synthesis of disturbance observers and parametric identification methods, is introduced. Proportional-Integral (PI) feedback is properly extended for both efficient planned motion tracking control and simultaneous fast disturbance estimation. In this fashion, design of additional high-gain disturbance observers becomes unnecessary. This is, on-line dynamic load uncertainty estimation is simultaneously achieved by proposed tracking control implementation. Analytical and numerical results prove the efficient and robust tracking performance of controlled system variables on planned smooth motion profiles and a high-accuracy estimation of unknown high-order variable disturbances.
Ivan Sanchez-Calleja,Alberto Martínez-Gutierrez,Ruben Ferrero-Guillén,Javier Díez-Gonzalez,Hilde Perez 한국정밀공학회 2024 International Journal of Precision Engineering and Vol.25 No.2
The advent of smart manufacturing (SM) has led to the creation of collaborative environments with cyber-physical systems (CPS) that generate added value. However, the performance of combined industrial operations between mobile CPS such as autonomous mobile robots (AMRs) and collaborative robots (cobots) is hampered by the high uncertainty between their relative spatial locations and the existence of heterogeneous communication protocols that create a barrier to their integration into production processes. For this reason, a novel contact system method (CSM) is proposed to determine the position of the AMR without the need for any additional hardware making use of an architecture that facilitates efficient communication between AMRs and cobots. For this purpose, a mathematical model has been defined to characterize the position of a spatial object with six degrees of freedom in order to calculate the deviation between the AMR and the cobot base. The proposed method has also been evaluated by quantifying the position and orientation error before and after applying the CSM. The effectiveness of the CSM method has been assessed in a real application case based on the feasibility of performing an assembly operation between a bearing and different shafts. The results show a significant improvement of 96.2% in positional accuracy and 85.4% in orientation compared to AMR accuracy. In addition, a 92.5% success rate was achieved in the assembly operation analyzed between a bearing and a shaft of the same diameter. Furthermore, the proposed architecture has enabled the coordination between the cobot and the AMR by automating the processes. Therefore, this work contributes to the field of SM by proposing a practical solution to the challenges of generating added value through the creation of collaborative environments with CPS.
Alejandra Mina Rosales,Elena Aznar,Carmen Coll,Ruben A. Garcia Mendoza,A. Lorena Urbano Bojorge,Nazario Felix Gonzalez,Ramon Martinez-Manez,Francisco del Pozo Guerrero,Jose Javier Serrano Olmedo 한국자기학회 2016 Journal of Magnetics Vol.21 No.3
Magnetic hyperthermia mediated by superparamagnetic particles is mainly based in sinusoidal waveforms as excitation signals. Temperature changes are conventionally explained by rotation of the particles in the surrounding medium. This is a hypothesis quite questionable since habitual experimental setups only produce changes in the magnetic module, not in the field lines trajectories. Theoretical results were tested by changing the waveform of the exciting signal in order to compare non-sinusoidal signals against sinusoidal signals. Experiments were done at different frequencies: 200 ㎑, 400 ㎑, 600 ㎑, 800 ㎑ and 1 ㎒. Superparamagnetic Iron Oxide samples (SPION), made of magnetite (Fe3O4) and suspended in water (100 ㎎/ml), were used. Magnetic field strength varies from 0.1 ± 0.015 KA/m to 0.6 ± 0.015 KA/m. In this study was observed that the power loss depends on the applied frequency: for 1 to 2.5 RMS current the responses for each signal are part of the higher section of the exponential function, and for 3.5 to 8 RMS current the response is clearly the decrement exponential function’s tale (under 1 × 10³ LER/gr).