Design parameter analysis for ATSC 1.0 single frequency networks based on receiver multipath handling performance

Hernandez-Flores, Mario A.,Galeano-Torres, Rodrigo,Garcia-Castillo, Miguel A.,Landeros-Ayala, Salvador,Matias-Maruri, Jose M. Electronics and Telecommunications Research Instit 2021 ETRI Journal Vol.43 No.4

This work proposes suitable network configurations for single frequency networks (SFNs) with ATSC 1.0 based on network coverage calculations and the laboratory multipath handling performance of commercial receivers. SFNs are widely used for delivering terrestrial digital television services because of their efficient use of the spectrum. In Mexico the analogue television transmissions switch-off occurred on 31 December 2016. Thus it is expected the adopted ATSC 1.0 system will be in force for the next several years despite the recent standardization of the ATSC 3.0 system. As ATSC 1.0 uses 8-VSB modulation the multipath handling capability of receivers is critical for the design of SFNs. The presented network planning results help develop technical normativity for implementing SFNs in Mexico and other countries that use ATSC 1.0. SFNs with transmitter separation up to 130 km are fully covered for outdoor reception mainly due to the directivity of the receiving antenna. Moreover for indoor reception at least 70% of an SFN coverage area can be achieved with a transmitter separation of up to 60 km depending on the radiated power and the transmitter antenna height.

Potential Control of Foodborne Pathogenic Bacteria by Pediococcus pentosaceus and Lactobacillus graminis Isolated from Fresh Vegetables

Gonzalez-Perez, C.J.,Vargas-Arispuro, I.,Aispuro-Hernandez, E.,Aguilar-Gil, C.L.,Aguirre-Guzman, Y.E.,Castillo, A.,Hernandez-Mendoza, A.,Ayala-Zavala, J.F.,Martinez-Tellez, M.A. The Korean Society for Microbiology and Biotechnol 2019 한국미생물·생명공학회지 Vol.47 No.2

The consumption of fresh vegetables has been related to recurrent outbreaks of foodborne diseases (FBD) worldwide. Therefore, the development of effective alternative technologies is necessary to improve the safety of these products. This study aimed to isolate and identify epiphytic lactic acid bacteria (LAB) from fresh fruits and leafy vegetables and characterize their antagonistic capacity due to their ability to produce bacteriocins or antibacterial compounds. For this, 92 LAB isolates from fruits and leafy vegetables were screened for antagonistic activity. Two strains with the highest and broadest antagonistic activities were selected for further characterization; one from cantaloupe melon (strain CM175) and one from cilantro leaves (strain C15). The cell-free supernatants (CFS) of CM175 and C15 were found to exhibit antagonistic activity against FBD-causing pathogens. The CM175 and C15 strains were identified as Pediococcus pentosaceus and Lactobacillus graminis, respectively. Notably, the P. pentosaceus CM175 CFS stopped the growth of Salmonella Typhimurium, Salmonella Saintpaul, Staphylococcus aureus, and Listeria monocytogenes, and delayed Escherichia coli O157:H7 growth. Moreover, L. graminis C15 CFS delayed the growth of all indicator pathogens, but did not completely stop it. Organic acids and bacteriocin-like molecules were determined to be possibly exerting the observed antagonistic activity of the identified LAB strains. Thus, application of the antagonistic compounds produced by Pediococcus pentosaceus and Lactobacillus graminis could be a novel and ecological strategy in developing antimicrobial biopreservatives for the food industry and mitigating FBD by reducing the biological contamination in fruit and vegetable orchards, mainly via their potential in controlling both gram-negative and gram-positive pathogenic bacteria.

Potential Control of Foodborne Pathogenic Bacteria by Pediococcus pentosaceus and Lactobacillus graminis Isolated from Fresh Vegetables

( C. J. Gonzalez-perez ),( I. Vargas-arispuro ),( E. Aispuro-hernandez ),( C. L. Aguilar-gil ),( Y. E. Aguirre-guzman ),( A. Castillo ),( A. Hernandez-mendoza ),( J. F. Ayala-zavala ),( M. A. Martinez 한국미생물생명공학회(구 한국산업미생물학회) 2019 한국미생물·생명공학회지 Vol.47 No.2

The consumption of fresh vegetables has been related to recurrent outbreaks of foodborne diseases (FBD) worldwide. Therefore, the development of effective alternative technologies is necessary to improve the safety of these products. This study aimed to isolate and identify epiphytic lactic acid bacteria (LAB) from fresh fruits and leafy vegetables and characterize their antagonistic capacity due to their ability to produce bacteriocins or antibacterial compounds. For this, 92 LAB isolates from fruits and leafy vegetables were screened for antagonistic activity. Two strains with the highest and broadest antagonistic activities were selected for further characterization; one from cantaloupe melon (strain CM175) and one from cilantro leaves (strain C15). The cell-free supernatants (CFS) of CM175 and C15 were found to exhibit antagonistic activity against FBD-causing pathogens. The CM175 and C15 strains were identified as Pediococcus pentosaceus and Lactobacillus graminis, respectively. Notably, the P. pentosaceus CM175 CFS stopped the growth of Salmonella Typhimurium, Salmonella Saintpaul, Staphylococcus aureus, and Listeria monocytogenes, and delayed Escherichia coli O157:H7 growth. Moreover, L. graminis C15 CFS delayed the growth of all indicator pathogens, but did not completely stop it. Organic acids and bacteriocin-like molecules were determined to be possibly exerting the observed antagonistic activity of the identified LAB strains. Thus, application of the antagonistic compounds produced by Pediococcus pentosaceus and Lactobacillus graminis could be a novel and ecological strategy in developing antimicrobial biopreservatives for the food industry and mitigating FBD by reducing the biological contamination in fruit and vegetable orchards, mainly via their potential in controlling both gram-negative and gram-positive pathogenic bacteria.

Participation of COX-1 and COX-2 in the contractile effect of phenylephrine in prepubescent and old rats

Gustavo Guevara-Balcazar,Israel Ramirez-Sanchez,Elvia Mera-Jimenez,Ivan Rubio-Gayosso,Maria Eugenia Aguilar-Najera,Maria C. Castillo-Hernandez 대한생리학회-대한약리학회 2017 The Korean Journal of Physiology & Pharmacology Vol.13 No.1

Vascular reactivity can be influenced by the vascular region, animal age, and pathologies present. Prostaglandins (produced by COX-1 and COX-2) play an important role in the contractile response to phenylephrine in the abdominal aorta of young rats. Although these COXs are found in many tissues, their distribution and role in vascular reactivity are not clear. At a vascular level, they take part in the homeostasis functions involved in many physiological and pathologic processes (e.g., arterial pressure and inflammatory processes). The aim of this study was to analyze changes in the contractile response to phenylephrine of thoracic/abdominal aorta and the coronary artery during aging in rats. Three groups of rats were formed and sacrificed at three distinct ages: prepubescent, young and old adult. The results suggest that there is a higher participation of prostanoids in the contractile effect of phenylephrine in pre-pubescent rats, and a lower participation of the same in old rats. Contrarily, there seems to be a higher participation of prostanoids in the contractile response of the coronary artery of older than pre-pubescent rats. Considering that the changes in the expression of COX-2 were similar for the three age groups and the two tissues tested, and that expression of COX-1 is apparently greater in older rats, COX-1 and COX-2 may lose functionality in relation to their corresponding receptors during aging in rats.

Participation of COX-1 and COX-2 in the contractile effect of phenylephrine in prepubescent and old rats

Guevara-Balcazar, Gustavo,Ramirez-Sanchez, Israel,Mera-Jimenez, Elvia,Rubio-Gayosso, Ivan,Aguilar-Najera, Maria Eugenia,Castillo-Hernandez, Maria C. The Korean Society of Pharmacology 2017 The Korean Journal of Physiology & Pharmacology Vol.21 No.4

Vascular reactivity can be influenced by the vascular region, animal age, and pathologies present. Prostaglandins (produced by COX-1 and COX-2) play an important role in the contractile response to phenylephrine in the abdominal aorta of young rats. Although these COXs are found in many tissues, their distribution and role in vascular reactivity are not clear. At a vascular level, they take part in the homeostasis functions involved in many physiological and pathologic processes (e.g., arterial pressure and inflammatory processes). The aim of this study was to analyze changes in the contractile response to phenylephrine of thoracic/abdominal aorta and the coronary artery during aging in rats. Three groups of rats were formed and sacrificed at three distinct ages: prepubescent, young and old adult. The results suggest that there is a higher participation of prostanoids in the contractile effect of phenylephrine in pre-pubescent rats, and a lower participation of the same in old rats. Contrarily, there seems to be a higher participation of prostanoids in the contractile response of the coronary artery of older than pre-pubescent rats. Considering that the changes in the expression of COX-2 were similar for the three age groups and the two tissues tested, and that expression of COX-1 is apparently greater in older rats, COX-1 and COX-2 may lose functionality in relation to their corresponding receptors during aging in rats.

Participation of COX-1 and COX-2 in the contractile effect of phenylephrine in prepubescent and old rats

Gustavo Guevara-Balcazar,Israel Ramirez-Sanchez,Elvia Mera-Jimenez,Ivan Rubio-Gayosso,Maria Eugenia Aguilar-Najera,Maria C. Castillo-Hernandez 대한약리학회 2017 The Korean Journal of Physiology & Pharmacology Vol.21 No.4

Vascular reactivity can be influenced by the vascular region, animal age, and pathologies present. Prostaglandins (produced by COX-1 and COX-2) play an important role in the contractile response to phenylephrine in the abdominal aorta of young rats. Although these COXs are found in many tissues, their distribution and role in vascular reactivity are not clear. At a vascular level, they take part in the homeostasis functions involved in many physiological and pathologic processes (e.g., arterial pressure and inflammatory processes). The aim of this study was to analyze changes in the contractile response to phenylephrine of thoracic/abdominal aorta and the coronary artery during aging in rats. Three groups of rats were formed and sacrificed at three distinct ages: prepubescent, young and old adult. The results suggest that there is a higher participation of prostanoids in the contractile effect of phenylephrine in pre-pubescent rats, and a lower participation of the same in old rats. Contrarily, there seems to be a higher participation of prostanoids in the contractile response of the coronary artery of older than pre-pubescent rats. Considering that the changes in the expression of COX-2 were similar for the three age groups and the two tissues tested, and that expression of COX-1 is apparently greater in older rats, COX-1 and COX-2 may lose functionality in relation to their corresponding receptors during aging in rats.