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Search Results: 1 - 10 of 691180 matches for " Jorge J. Ramírez-García "
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Atypical Variations of Water Conductivity Prior to Tectonic Earthquakes  [PDF]
Fidel Martínez-García, Arturo Colín-Cruz, Salvador Adame-Martínez, Jorge J. Ramírez-García
International Journal of Geosciences (IJG) , 2015, DOI: 10.4236/ijg.2015.612108
Abstract: Within the framework of precursor events related to earthquakes, this paper analyzes the possible effect on the aquatic environment of the surrounding energy that accompanies earthquakes, particularly in the area where oceanic and continental plates collide (Cocos Plate and North American Plate, south of Mexico). As a preamble, the types of precursor events, characteristics, and their possible origin are described. A project was designed under the assumption that in areas with high frequency and intensity seismicity there is an electrical and electromagnetic potential promoter which is detectable and assessable indirectly by measuring water conductivity behavior, which also may have atypical variations of data; the outcome of intensive conductivity monitoring in different settings, natural as well as manmade (wellsprings, artesian well and a cistern), are presented herein. The results of the conductivity monitoring for seven months, highlight two patterns in data behavior: one pattern shows the subtle dependence of data behavior on the geographic location of data monitoring instruments, revealing that could have a slight relationship between areas with increased seismic frequency and intensity and the presence of atypical conductivity variations. Another pattern reveals the possible relationship between atypical variations in conductivity and subsequent earthquake events; a total of 241 seismic events were analyzed and 59 of them are provided as evidence related with patterns mentioned.
Natural Water Conductivity Behavior within the Seismic Pacific Coast of Southern Mexico  [PDF]
Fidel Martínez-García, Arturo Colín-Cruz, Alberto Pereira-Corona, Salvador Adame-Martínez, Jorge J. Ramírez-García
Open Access Library Journal (OALib Journal) , 2016, DOI: 10.4236/oalib.1102836
Abstract: Clouse to faults or unstable areas where an earthquake could happen with capacity of affecting buildings or infrastructure, there is often a previous energy that wanders around surroundings, this energy regularly is associated to electromagnetic emissions that generate an electric potential frequently studied as very, ultra-low and extreme frequency emissions (VLF-ULFELF_ EM) by remote sensing; under the assumption that this natural potential exist, in aquatic environment within the micro-seismic active area in the coastal border of Guerrero and Oaxaca estates, Mexico, an intensive conductivity monitoring in two artesian well was carried out. The results of intensive conductivity (μS/cm) monitoring done since March to July of 2015, using a low-cost Data logger sensor are presented. The results obtained of the study of 235 seismic events show that 61.64% of them manifest prior conductivity oscillation versus 38.36% of early conductivity oscillation; a discussion of the origin of such oscillation and the possible relation with to recharge flux, ground light compression, ground tilt, local electromagnetic energy emissions, human interaction, was debated. The data analysis for long periods of conductivity monitoring and seismic events show that when the number of seismic events became intense, conductivity decreases and vice versa, resulting large fluctuations that grew over time lake waves, within the studied area appears to be there is a possible previous long term energy oscillation associated to the process of earthquakes manifestation around.
Which stressors are responsible for the worsening in the clinical symptomatology of lupus?  [PDF]
M. I. Peralta-Ramírez, J. Jiménez-Alonso, M. Pérez-García
Health (Health) , 2009, DOI: 10.4236/health.2009.14051
Abstract: Objective: The purpose of this study was to test which stressors worsen the symptoms perceived by patients with lupus, thus broadening and corroborating results obtained in a previous study published in Psychosomatic Medicine. Methods: In order to examine this question, we selected 43 patients with lupus whose symp-toms worsened due to the effects of daily stress. These patients were divided into two groups: patients whose increase in clinical lupus symp-tomatology was predicted by an increase in daily stressors on the same day (G1) and pa-tients whose increase in clinical lupus symp-tomatology was predicted by an increase in daily stressors the day before and the same day (G2). Later, three factorial analyses were con-ducted with the items related to stressors and the items related to lupic symptoms. Results: The results showed that in G1 there were three factors that made up a total of 35.08% of the explained variance. The stressors associated with certain symptoms of the illness in this group are feeling ill or being worried about their physical appearance, with the main stressor being the illness itself. However, in G2, two factors were found that made up a total of 40.37% of the explained variance for lag=0 and 38.67% for lag=1. The stressors associated with the majority of the lupus symptoms are of an interpersonal and work-related nature. This as-sociation was maintained when we carried out the factorial analyses with the items of the symptoms from the following day. Conclusions: The interpersonal and work-related stressors are related to a worsening in the majority of the lupic symptoms in the patients whose sympto-matology worsens as a result of daily stress experienced the day before.
Compared gametophytic development of three species of Phebodium (Polypodiaceae, s.str.)
rez-García,Blanca; Riba,Ramón; Mendoza,Aniceto; Reyes J.,Irma;
Revista de Biología Tropical , 1998,
Abstract: a comparison was made of the gametophytic development of phlebodium araneosum, p. pseudoaureum and p. decumanum. spores were collected from several mexican localities ranging in altitude from 30 to 2300 m and sown on agar with mineral salts. similarities in germination type and prothallial development were observed. adult gametophytes are cordate-spathulate to cordate-reniform; gametangia are of the tipical type of the common leptosporangiate ferns. all three species share similar morphogenetic features of the gametophytes, and these do not lend additional characteristics to support the distinction of phlebodium from polypodium, microgramma and niphidium, as regard the sexual phase.
Compared gametophytic development of three species of Phebodium (Polypodiaceae, s.str.)
Blanca Pérez-García,Ramón Riba,Aniceto Mendoza,Irma Reyes J.
Revista de Biología Tropical , 1998,
Abstract: A comparison was made of the gametophytic development of Phlebodium araneosum, P. pseudoaureum and P. decumanum. Spores were collected from several Mexican localities ranging in altitude from 30 to 2300 m and sown on agar with mineral salts. Similarities in germination type and prothallial development were observed. Adult gametophytes are cordate-spathulate to cordate-reniform; gametangia are of the tipical type of the common leptosporangiate ferns. All three species share similar morphogenetic features of the gametophytes, and these do not lend additional characteristics to support the distinction of Phlebodium from Polypodium, Microgramma and Niphidium, as regard the sexual phase. Una comparación del desarrollo del gametofito de Phlebodium araneosum, P. pseudoaureum y P. decumanum fue hecha. Las esporas fueron sembradas en agar con sales minerales. Similitudes en el tipo de germinación y desarrollo protálico fueron observadas. Los gametofitos adultos fueron cordiforme-espatulados a cordiforme-reniformes; los gametangios son del tipo común de los helechos leptosporangiados. Las tres especies muestran caracteristicas morfogenéticas del gametofito similares y no a aden características adicionales que apoyen la distinción entre Phlebodium, Polypodium, Microgramma y Niphidium, por lo que se refiere a la fase sexual.
Enfermedad plus en la retinopatía del prematuro de gestación múltiple: Análisis de riesgo
García-Serrano,J.L.; Ramírez-García,M.C.; Pi?ar-Molina,R.;
Archivos de la Sociedad Espa?ola de Oftalmología , 2009, DOI: 10.4321/S0365-66912009000400005
Abstract: purpose: to analyze the risk factors associated with plus disease in retinopathy of prematurity (rop). method: over a period of 8.5 years we carried out a prospective study of rop in twins and triplets. fifty-four multiple-birth infants with low birth weight (≤1500 g) and low gestational age (32≤ weeks) were admitted to the university hospital of granada. results: logistic regression analyses showed the following variables to be associated with an increased risk of plus disease: severe rop, large area of avascular retina, low gestational age, low birth weight, a patent ductus arteriosus, length of mechanical ventilation, adverse events increase, low 5 min apgar scores and poor postnatal weight gain (in the first 4 to 6 weeks of life). using multiple logistic regression, only the grade of rop (or: 5.5; p < 0.009) and poor postnatal weight gain (or: 0.58; p < 0.04) were predictive factors of development of plus disease. infants with ?plus? disease gained an average 3.9 ± 3.1 g/day in the first 6 weeks of life, compared to a mean of 11.84 ± 8.3 g/day for those without plus disease (p < 0.0001). conclusion: advanced rop stages and poor weight gain were the most significant factors associated with plus disease. twins who gained weight at more than 7 g/day in the first 4-6 weeks of life had a significantly reduced risk of plus disease. a good weight gain is an effective strategy against avoidable blindness due to rop.
Enfermedad plus en la retinopatía del prematuro de gestación múltiple: Análisis de riesgo Retinopathy of prematurity in multiple births: risk analysis for plus disease
J.L. García-Serrano,M.C. Ramírez-García,R. Pi?ar-Molina
Archivos de la Sociedad Espa?ola de Oftalmología , 2009,
Abstract: Objetivo: Determinar los factores de riesgo asociados con la enfermedad plus en la retinopatía del prematuro (ROP). Método: En los últimos 8,5 a os, realizamos un estudio prospectivo sobre la ROP en gemelos y trillizos. Cincuenticuatro prematuros nacidos de parto múltiple con peso (≤1500 gr) y edad gestacional (≤32 semanas). Resultados: Los factores que presentaron asociado un mayor riesgo de enfermedad plus fueron: grado avanzado de ROP, mayor área sin vascularizar, menor edad gestacional, menor peso al nacer, existencia de ductus arteriovenoso persistente, mayor número de días intubado, mayor número de eventos adversos, menor puntaje en el test Apgar 2 y una menor ganancia de peso postnatal. Con regresión logística binaria, sólo el grado más avanzado de ROP (OR: 5,5; p < 0,009) y la menor ganancia de peso posnatal (OR: 0,58; p < 0,04) resultaron factores predictivos del desarrollo de la enfermedad plus. En las 4-6 primeras semanas de vida, los ni os con enfermedad plus obtenían una pobre ganancia media de peso de 3,9 ± 3,1 gr/día frente a los 11,84 ± 8,3 gr/día que alcanzaban aquellos sin enfermedad plus (p < 0,0001). Conclusiones: Los factores más significativamente asociados con la enfermedad plus eran el estadio avanzado de ROP y la pobre ganancia de peso. Los gemelos que ganan más de 7 gr/día de peso, en las primeras 4-6 semanas de vida, significativamente reducen el riesgo de enfermedad plus. Una buena ganancia de peso postnatal es una estrategia efectiva contra la ceguera evitable de la ROP. Purpose: To analyze the risk factors associated with plus disease in retinopathy of prematurity (ROP). Method: Over a period of 8.5 years we carried out a prospective study of ROP in twins and triplets. Fifty-four multiple-birth infants with low birth weight (≤1500 g) and low gestational age (32≤ weeks) were admitted to the University Hospital of Granada. Results: Logistic regression analyses showed the following variables to be associated with an increased risk of plus disease: severe ROP, large area of avascular retina, low gestational age, low birth weight, a patent ductus arteriosus, length of mechanical ventilation, adverse events increase, low 5 min Apgar scores and poor postnatal weight gain (in the first 4 to 6 weeks of life). Using multiple logistic regression, only the grade of ROP (OR: 5.5; p < 0.009) and poor postnatal weight gain (OR: 0.58; p < 0.04) were predictive factors of development of plus disease. Infants with plus disease gained an average 3.9 ± 3.1 g/day in the first 6 weeks of life, compared to a mean of 11.84 ± 8.3 g/day for those
Chromosomal mapping of rRNA genes, core histone genes and telomeric sequences in Brachidontes puniceus and Brachidontes rodriguezi (Bivalvia, Mytilidae)
Concepción Pérez-García, Jorge Guerra-Varela, Paloma Morán, Juan J Pasantes
BMC Genetics , 2010, DOI: 10.1186/1471-2156-11-109
Abstract: Brachidontes puniceus and B. rodriguezi both have 2n = 32 chromosomes but differing karyotype composition. Vertebrate-type telomeric sequences appear at both ends of every single chromosome. B. puniceus presents a single terminal major rRNA gene cluster on a chromosome pair while B. rodriguezi shows two. Both mussels present two 5S rDNA and two core histone gene clusters intercalary located on the long arms of two chromosome pairs. Double and triple-FISH experiments demonstrated that one of the 5S rDNA and one of the major rDNA clusters appear on the same chromosome pair in B. rodriguezi but not in B. puniceus. On the other hand, the second 5S rDNA cluster is located in one of the chromosome pairs also bearing one of the core histone gene clusters in the two mussel species.Knowledge of the chromosomal distribution of these sequences in the two species of Brachidontes is a first step in the understanding of the role of chromosome changes on bivalve evolution.Over recent years, an increasing number of molecular studies have focused on the elucidation of the phylogenetic relationships among species of bivalves in order to further reveal their evolutionary history [1]. Nevertheless, cytogenetic comparisons between species remain quite rare mainly due to difficulties in obtaining good chromosome banding patterns [2]. This fact, together with the small differences in chromosome size and morphology in many species of bivalves, makes the unequivocal identification of each chromosome pair very difficult and therefore, complicates cytogenetic comparisons.Fluorescent in situ hybridization (FISH) allows combining cytogenetic and molecular techniques, improving our understanding of genome organization. The chromosomal mapping of different types of DNA sequences in bivalves has greatly increased over the last years [2-4]. Although the information gained so far is of great importance in the analysis of chromosome evolution in bivalves, the data obtained are still scarce and focuse
Low Dose Total Body Irradiation (600 cGy) as a Conditioning Regimen in Allogenic Hematopoietic Stem Cell Transplant in Children with Acute Lymphoblastic Leukemia  [PDF]
Alberto Olaya-Vargas, Martín Pérez-García, Nideshda Ramírez-Uribe, M. Angeles Del Campo-Martinez, Gerardo Lopez-Hernández, Montserrat Hernández-García, Jorge Amador-Zarco, Guadalupe Garcia-Vega, Yadira Melchor-Vidal, Marta Zapata-Tarres, Rocío Cárdenas-Cardos, Roberto Rivera-Luna
Journal of Cancer Therapy (JCT) , 2016, DOI: 10.4236/jct.2016.78061
Abstract: Total body irradiation (TBI) is conditioning regimen in children with acute lymphoblastic leukemia (ALL) with a very high risk of relapse or in those who have not achieved remission and have relapsed and subsequently received allogenic hematopoietic stem cell transplantation (HSCT). A retrospective evaluation of 33 ALL patients in full remission with an indication of HSCT was performed to evaluate overall survival (OS) and event-free survival (EFS). The inclusion criteria included a myeloablative conditioning regimen of TBI at a dose of 600 cGy. The observed OS at 5 years was 50%, and the EFS of 32% we observed difference in the EFS stem cell origin; the peripheral blood (PB) 60%, and the umbilical cord blood (UC) accounted for 40%. Overall, 45% had a documented chimerism. The OS at 5 years from patients with chimeras was 75%, while those without chimeras had an OS at 5 years of 25%. The mortality in the first 100 days was 24%. A total of 24.2% of children presented with acute graft versus-host disease (GVHD), while 33% had chronic GVHD. Currently, there is no general agreement among all international centers regarding the optimum TBI dose. Our study reports an acceptable range of adverse events with a relatively low dose of 600 cGy.
Metabolic syndrome occurrence in university students from México City: The binomium HDL/waist circumference is the major prevalence factor  [PDF]
J. Rafael Jiménez-Flores, Miguel Murguía-Romero, M. Isabel Mendoza-Ramos, Santiago Sigrist-Flores, Norma Y. Rodríguez-Soriano, Lilia I. Ramírez-García, Ramiro Jesús-Sandoval, M. Araceli álvarez-Gasca, Esther Orozco, Rafael Villalobos-Molina, A. René Méndez-Cruz
Open Journal of Preventive Medicine (OJPM) , 2012, DOI: 10.4236/ojpm.2012.22026
Abstract: Objective: Metabolic Syndrome (MetS) is the leading cause to develop type 2 diabetes worldwide. We examined associations of MetS components early in life, and their use as risk factors of acquiring MetS. Method: We used an international definition of MetS. Subjects were categorized into “Healthy”/“Not Healthy”, altered parameters are low HDL-cholesterol, large waist circumference (WC), hypertriacylglycerolemia, hypertension, and hyperglycemia, in 32 combinations (2^5) with two values (altered/not altered). MetS was identified with three or more altered parameters. Results: A total of 3424 students (ages 17 - 24 years) participated in the survey, and 2475 were “Not Healthy” showing at least 1 parameter altered; from them 49.6% showed low blood HDL either alone or combined, 38.2% had altered waist circumference either alone or combined; while 18.1% showed hypertriacylglycero-lemia either alone or combined. Hypertension and hyperglycemia were the lowest in frequency. Conclusion: We propose that the binomium HDL/ Waist Circumference is the main prevalence factor to develop MetS in the asymptomatic young population, followed by hypertriacylglycerolemia which together define MetS; while hypertension and hyperglycemia seem to occur later in MetS.
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