Papers by nicolas ramirez
Urban Climate, 2021
Salt precipitation and its induced problems are increasingly prominent with the development of de... more Salt precipitation and its induced problems are increasingly prominent with the development of deep and ultra-deep tight sandstone gas reservoirs with high salinity formation water. In this paper, the change of porosity and permeability of a series of tight sandstone was measured, and then the morphology and occurrence state of crystalloid salt within the pore was observed by SEM. Meanwhile, high-pressure mercury injection analyzed the changes of pore size distribution. Experimental results show that salt precipitation could affect the porosity and permeability, which decreases by 53% and 65% after salt precipitation, respectively. The occurrence state of the crystalloid salt can be divided into three models: superposition growth along with the intergranular pore-fractures/natural micro-fractures, lamellar growth attached to the surface of the hydrophilic mineral like I/S interstratified mineral and the individual particles located in the corner of the pore. When the size of crystalloid salt is closer to the pore size distribution of tight sandstone, it will cause cracks and pore throat blockage easily. It is suggested that salt wash pretreatment should be carried out before analysis of tight sandstone with porosity less than 5%.
Revista Fitotecnia Mexicana, 2012
En México existe la cultura y tradición para el consumo de frijol en grano (Phaseolus vulgaris L.... more En México existe la cultura y tradición para el consumo de frijol en grano (Phaseolus vulgaris L.), no así para el consumo de ejote (vaina fresca de frijol), esto pese a su alto contenido de proteínas, carbohidratos, fibras, calcio y vitaminas. En el Estado de México, la producción de frijol ejotero no satisface la demanda interna de ejote (0.9 a 1.1 kg per capita), por lo que es necesario importarlo. El bajo rendimiento y calidad nutrimental del ejote puede deberse a la falta de manejo apropiado del cultivo y a la falta de adaptación de las variedades utilizadas. Por ello, el presente estudio se hizo para dilucidar la naturaleza de esta interacción en frijol ejotero. Se compararon tres variedades: ‘Strike’ y ‘Black Valentine’ de crecimiento determinado, y ‘Hav-14’ de crecimiento indeterminado, en dos ambientes contrastantes (Montecillo, de clima semiárido; y San Pablo Ixayoc, de clima templado) en el Estado de México. La siembra se hizo el 7 de mayo de 2008, bajo régimen de lluvia ...
Energy Procedia, 2017
District heating networks are commonly addressed in the literature as one of the most effective s... more District heating networks are commonly addressed in the literature as one of the most effective solutions for decreasing the greenhouse gas emissions from the building sector. These systems require high investments which are returned through the heat sales. Due to the changed climate conditions and building renovation policies, heat demand in the future could decrease, prolonging the investment return period. The main scope of this paper is to assess the feasibility of using the heat demand-outdoor temperature function for heat demand forecast. The district of Alvalade, located in Lisbon (Portugal), was used as a case study. The district is consisted of 665 buildings that vary in both construction period and typology. Three weather scenarios (low, medium, high) and three district renovation scenarios were developed (shallow, intermediate, deep). To estimate the error, obtained heat demand values were compared with results from a dynamic heat demand model, previously developed and validated by the authors. The results showed that when only weather change is considered, the margin of error could be acceptable for some applications (the error in annual demand was lower than 20% for all weather scenarios considered). However, after introducing renovation scenarios, the error value increased up to 59.5% (depending on the weather and renovation scenarios combination considered). The value of slope coefficient increased on average within the range of 3.8% up to 8% per decade, that corresponds to the decrease in the number of heating hours of 22-139h during the heating season (depending on the combination of weather and renovation scenarios considered). On the other hand, function intercept increased for 7.8-12.7% per decade (depending on the coupled scenarios). The values suggested could be used to modify the function parameters for the scenarios considered, and improve the accuracy of heat demand estimations.
Parasite Epidemiology and Control, 2016
A cross sectional study was undertaken to determine the prevalence and intensity of parasitic inf... more A cross sectional study was undertaken to determine the prevalence and intensity of parasitic infections in dairy cattle in the high tropics of Colombia. A total of 1003 rectal samples were collected from dairy cows at 29 farms between May and June 2014 to represent the number of farms, age groups, and size of the 65,000-cow population in the municipality of San Pedro de los Milagros. Coprological techniques were used to detect gastrointestinal nematodes, liver flukes, coccidian oocysts, and first larval stage counts of Dictyocaulus viviparus. In order of decreasing prevalence, the following parasites were detected: coccidial oocyst (36.7%; 95% CIs, 31.6-42.7), strongyle nematodes (31.6%, 27.8-35.4), liver flukes (30.9%, 21.5-37.5), cestodes (8.4%, 7.1-9.7), and D. viviparus (5.4%, 3.4-7.5). Co-infections by all possible combinations of the three most predominant groups occurred in 11 to 15% of the animals. There were significant differences in infection rates between age groups, with higher risk of liver fluke infection in animals older than 1 year of age (odds ratio (OR) = 3.2), but lower presence for coccidia and strongyles (OR = 0.19 and 0.51, respectively). For Fasciola hepatica, within-herd prevalences of N 25% in 16 farms and 94 of 281 (33.5%) animals with N 5 eggs per gram (epg) indicate that significant production losses are likely occurring. The variation in the prevalence of gastrointestinal parasites and liver flukes, together with the level of infection among age groups, could be used in integrated management programs to establish selective anthelmintic treatments and select for heritable traits of host resistance. These results serve as a baseline for future studies to determine the success of control measures and should increase awareness that subclinical parasitism is widespread in the livestock sector.
Revista Colombiana De Ciencias Pecuarias, 2014
Background: molecular markers for genetic resistance can be used to control mastitis in dairy cat... more Background: molecular markers for genetic resistance can be used to control mastitis in dairy cattle. The Major Histocompatibility Complex and the Toll-like receptor 4 (TLR4) are two promising genes that warrant investigation. Objective: to identify associations between genotypes of BoLA-DRB3 locus and T4CRBR2 fragment and subclinical mastitis (SM). Methods: 996 lactating cows from 32 herds comprising Holstein (80%), Holstein x Jersey cross (12.5%), and other crosses (7.5%) were evaluated monthly during two years, diagnosed for SM and genotyped for the second exon of BoLA DRB3 and the TLR4 coreceptor-binding region 2 (T4CRBR2) using a Polymerase chain reaction-restriction fragment length polymorphism technique (PCR-RFLP). The association between candidate alleles and subclinical mastitis was measured by logistic regression. Results: the most frequently observed alleles for BoLA-DRB3 were DRB3.2 *8, *22, *24, *16, *10, *23, *gba, *11, *2, *mbb, *jba, *3, and *15, accounting for 58.9% of the population. Frequencies for T4CRBR2 alleles A and B were 0.352 and 0.647, respectively. Based on 57,408 observations during the period, the mean SM prevalence was 16.2% (95% CI 13.0 and 19.4) per udder quarter and 37.6% (95% CI 32.1 and 43.2) per cow. The predominant microorganisms isolated from SM quarters were Streptococcus agalactiae and Coagulase-Negative Staphylococci (CNS). Allele DRB3.2 *23 was associated with SM occurrence and CNS infection. No alleles were associated with Streptococcus agalactiae infection. Allele *mbb was associated with occurrence of CNS infection and alleles *jba and *15 were associated with resistance to CNS infection.
Journal of dual diagnosis, Jan 29, 2015
Only a few studies in patients with first-episode psychosis have included gender in the study hyp... more Only a few studies in patients with first-episode psychosis have included gender in the study hypothesis or considered this a primary study variable. The aim of this study was to explore the influence of gender in the pattern of substance use in patients with first-episode psychosis. This is a sub-analysis of a randomized, open clinical trial that compared one-year treatment retention rates of patients with first-episode psychosis randomized to haloperidol, olanzapine, quetiapine, risperidone, or ziprasidone. Our sub-analysis included 85 men and 29 women. Substance use was relatively high among these patients and differed significantly by gender. Men were more likely to use substances overall than women (89.4% for men vs. 55.2% for women); χ(2) = 16.2, df = 1, p < .001, and were also more likely to use alcohol (χ(2) = 13, df = 1, p < 0.001), cannabis (χ(2) = 9.9; df = 1, p < 0.002), and cocaine (χ(2) = 10.3; df = 1, p < 0.001), compared to women. While there were no gend...
Actas españolas de psiquiatría
Asperger Syndrome (AS) is characterized by a qualitative disorder of social interaction, a patter... more Asperger Syndrome (AS) is characterized by a qualitative disorder of social interaction, a pattern of restrictive, repetitive and stereotyped behavior, interests and activities, with normal intellectual capacity and normal language skills in the areas of grammar and vocabulary. Since its inclusion in international taxonomies, there has been much controversy regarding its nosological validity. A patient with a diagnosis of AS in adulthood is described. Results from the psychopathological, personality and cognitive functioning assessment are included. Asperger Syndrome can also be diagnosed in adulthood and should be suspected whenever retrospective information and clinical assessment point to this diagnosis.
Psychiatry Research, 2003
The 5-HT2A receptor binding parameters using [3H]ketanserine and its intracellular signal inosito... more The 5-HT2A receptor binding parameters using [3H]ketanserine and its intracellular signal inositol 1,4,5 trisphosphate (IP3) concentrations were determined in platelets from schizophrenic patients so as to assess differences with respect to a control group and to a standardized antipsychotic drug treatment. Seventy-five antipsychotic-free patients with a DSM-IV diagnosis of paranoid schizophrenia were included in the study. Blood samples were collected before the onset of antipsychotic treatment (baseline values) and after 3 weeks of treatment. Antipsychotic-free schizophrenic patients showed significantly increased basal 5-HT2A densities in comparison to the control group, together with a significantly increase (23%) in the 5-HT2A binding density in those patients treated with risperidone. These changes could be attributed to an up-regulation of 5-HT2A receptors caused by previous treatment with antipsychotic drugs, which is consistent with the chronic effect of 5-HT2A antagonists to up-regulate the number of binding sites. With regard to second messenger IP3 concentrations, basal concentrations in schizophrenic patients were not significantly different from control values, nor was there any significant difference between basal vs. posttreatment values. These results are possibly related to failure of second messenger systems of…
Psychiatry Research, 2010
Early identification of schizophrenia in patients with a first episode of psychosis (FEP) may hel... more Early identification of schizophrenia in patients with a first episode of psychosis (FEP) may help to avoid inappropriate treatment and may enhance long-term outcome by addressing issues such as family network, treatment adherence and functional and symptomatic outcome. It was the aim of the study to determine baseline variables that significantly predicted a diagnosis of schizophrenia in patients with FEP. The sample consisted of 133 FEP patients hospitalized for at least 6 weeks, in whom a DSM-IV diagnosis was confirmed after 1 year follow-up. Patients were divided into two groups, those with a diagnosis of schizophrenia (Schizophrenia group, n = 63; 47.8%), and those with other psychosis, who were grouped under Non-Schizophrenic Psychosis (NSP, n = 70; 52.2%). Sociodemographic (marital status, educational level) and clinical variables were recorded for each patient. Substance use (alcohol, cannabis and cocaine) did not statistically differ between the two groups. Absence of characteristics defined as criteria for good prognosis, lack of ≥ 20% improvement in the total Positive and Negative Syndrome Scale score at 6 weeks, and a poor premorbid adjustment as determined by the Premorbid Adjustment Scale score significantly predicted the presence of schizophrenia. The regression model including these three variables achieved a predictive value of 76.3%, with a sensitivity of 74.6% and a specificity of 77.9%.
Psychiatry Research, 2007
The purpose of this study was to determine whether platelet serotonin-2A (5-HT 2A) binding sites ... more The purpose of this study was to determine whether platelet serotonin-2A (5-HT 2A) binding sites and inositol 1,4,5 trisphosphate (IP3) concentrations before treatment can identify olanzapine-responsive patients. The study included 21 never medicated, first-episode schizophrenia patients (antipsychotic-naïve) and 21 patients with a DSM-IV-TR diagnosis of paranoid schizophrenia who had not received depot antipsychotic treatment in the previous 6 months or oral antipsychotic or antidepressant treatment in the previous 2 months (antipsychotic-free). In the antipsychotic-naïve group, olanzapine responders had a significantly lower number of 5-HT 2A receptors and lower IP3 concentrations at baseline than non-responders. The combination of baseline 5-HT 2A and IP3 values significantly predicted an improvement in negative symptomatology after 6 weeks of treatment with olanzapine. In the antipsychotic-free group, responders had significantly higher positive and lower negative symptomatology at baseline, together with a reduced number of 5-HT 2A receptors. However, basal 5-HT 2A receptors or IP3 concentrations did not significantly predict positive, negative or general clinical response. The reported results suggest that platelet 5-HT 2A binding might be a trait marker that could help to identify those patients likely to show greater improvement in negative symptomatology after olanzapine treatment.
Psychiatry Research, 2012
The aim of this study was to compare the 12-month effectiveness of several second-generation anti... more The aim of this study was to compare the 12-month effectiveness of several second-generation antipsychotic drugs, with that of haloperidol in never-treated patients with first-episode psychosis. In total, 114 patients without life time exposure to any psychotropic medication were randomized to haloperidol, olanzapine, risperidone, quetiapine or ziprasidone. Primary outcome was time to all-cause discontinuation. Secondary outcomes included discontinuation rates and symptom change as measured by the Positive and Negative Syndrome Scale (PANSS). The overall discontinuation rate 64%. At 12 months, the proportion of patients discontinuing treatment was 40.0% for olanzapine, 56.5% for quetiapine, 64.0% for risperidone, 80.0% for ziprasidone and 85.7% for haloperidol. Mean time to antipsychotic discontinuation was higher in patients randomized to second-generation antipsychotics than in those taking haloperidol. Significantly lower discontinuation was noted in patients on olanzapine than on haloperidol, or ziprasidone. Our results suggest that olanzapine might lead to longer treatment continuation in treatment naïve FEP patients than haloperidol and, possibly ziprasidone. Global psychopathology was significantly less reduced by haloperidol than with each individual SGA in this earliest phase of treatment.
Nicotine & Tobacco Research, 2006
Numerous studies have identified a variety of reasons that youths give for starting smoking. Few ... more Numerous studies have identified a variety of reasons that youths give for starting smoking. Few efforts have been made, however, to identify seasonal variations in initiation. This study was an attempt to fill that void. We examined data from 342 youths participating in a mandated smoking education and cessation program in Texas. Data were collected based on responses to questions in participant workbooks, including an item asking participants about the month in which they started smoking. A total of 47% of the participants indicated that they started smoking in May through August (chi2 = 91.42, df = 3). Post-hoc analyses indicated that significantly more youths than expected began smoking in May and June, whereas significantly fewer youths than expected began smoking in September and November. Unsupervised time out of school during the first months of summer vacation is a period of increased danger for smoking initiation. The significantly lower rates during September seem to be related to the beginning of school.
International Journal of Psychiatry in Clinical Practice, 1999
ABSTRACT The objective of the study was the evaluation of the influence of various clinical and s... more ABSTRACT The objective of the study was the evaluation of the influence of various clinical and sociodemographic factors on the perception of quality of life in 141 patients with depression (CIE-10). We used a multivariate analysis of logistic regression to predict lower quality of life and well-being. The best predictive variables for quality of life were the Hamilton Rating Scale for Depression (HAM-D) score, the number of episodes, personality disorder and gender. For well-being, the best predictive variables were HAM-D score, type of family environment, Hamilton Rating Scale for Anxiety (HAM-A) score, educational level and marital status. We conclude that the severity of the symptoms is the main factor influencing the appraisal of the quality of life, while sociodemographic variables play a more limited role.
Human Psychopharmacology: Clinical and Experimental, 2007
Objective A post-hoc analysis of the data from a randomised clinical trial involving prescription... more Objective A post-hoc analysis of the data from a randomised clinical trial involving prescription of antipsychotic treatment to never treated first-onset psychotic patients was used to compare the weight change after 6-week olanzapine treatment (standard tablets vs. orally disintegrating formulation). Method In the subgroup of 38 patients randomised to olanzapine, standard olanzapine tablets were non-randomly and consecutively prescribed to the first 19 patients, with the orally disintegrating formulation being prescribed to the following 19 patients. Results After 6-week treatment with olanzapine, a significant higher increase in weight was noted in those patients on standard tablets (mean weight increase 6.3 AE 1.9 Kg) as compared to those on orally disintegrating olanzapine (mean weight increase 3.3 AE 3.2 Kg) (F ¼ 7.7; p ¼ 0.009). BMI increase was also significantly higher in the olanzapine tablet group (mean increase of 2.1 Kg/m 2 as compared with 1.1 Kg/m 2 in the orally disintegrating group) (F ¼ 4.7; p ¼ 0.036). Substantial weight gain (SWG) (!7% increase from baseline weight) was noted in 84.2% (n ¼ 16) of the olanzapine tablet patients and in 31.6% (n ¼ 6) of the orally disintegrating olanzapine patients, with the olanzapine tablet group showing a significant increase in the mean percentage of weight gain (F ¼ 4.0; p ¼ 0.014). Conclusions Partial sublingual absorption occurring with orally disintegrating olanzapine may bypass gastrointestinal metabolisation and hence lead to differences in metabolite versus parent compound ratios. However, the need arises to replicate the present study with a longer follow-up.
European Psychiatry, 2003
A single case of a patient suffering from a first psychotic episode and the differential diagnose... more A single case of a patient suffering from a first psychotic episode and the differential diagnoses between affective and psychosis is performed throughout the combined use of peripheral serotonergic markers and clinical psychopathological scales during a 6-months follow-up. The results suggest the need of performing further studies combining biological and clinical markers of psychiatric disorders.
Current Psychiatry Reviews, 2006
Depressive symptoms in schizophrenia patients are not usually the primary therapeutic goal, as th... more Depressive symptoms in schizophrenia patients are not usually the primary therapeutic goal, as the psychiatric evaluation of the schizophrenia is generally based in the assessment of the positive and negative syndrome. However, direct approach of the pure depressive symptoms in schizophrenia is of capital importance from both prognostic and therapeutical perspective. This paper reviews the recently published evidence on the treatment of depressive symptoms in schizophrenia patients, with a special emphasis on the efficacy of different pharmacological families. It also includes studies on the antidepressant effect and pharmacological profile of second-generation antipsychotics. Finally, it addresses the possible confusion between depressive and negative symptoms/extrapyramidal side effects of antipsychotic treatment.
Editorial …, 2010
... Sección 4. Contexto morfofisiológico y patológico. Martha Olivera, Omar Camargo, Joaquín Angu... more ... Sección 4. Contexto morfofisiológico y patológico. Martha Olivera, Omar Camargo, Joaquín Angulo Arizala, Carlos Tamayo Patiño, Nicolás Ramírez, Leonardo Duque Muñoz, Jhon Didier Ruiz Buitrago. Resumen. Capítulo 13: Desarrollo de la glándula mamaria (mamogénesis). ...
Iatreia, 2004
INTRODUCCIÓN La leche es uno de los principales alimentos para el consu-mo humano, pero en el pro... more INTRODUCCIÓN La leche es uno de los principales alimentos para el consu-mo humano, pero en el proceso de producción desde el origen (granja) puede estar sometida a múltiples tipos de contaminación. Una fuente de contaminación muy importante son los pesticidas, entre ...
… de Ciencias Pecuarias, 2009
Kinetics of fenthion excretion in milk following a topical application in two breeds of dairy cat... more Kinetics of fenthion excretion in milk following a topical application in two breeds of dairy cattle ¤ Cinética de la eliminación de fention en leche luego de una aplicación tópica en dos razas de ganado lechero Cinética da excreção do Fenthion em leite aplicado de forma tópica em gado Holandês e HolandêsXBON
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Papers by nicolas ramirez