Universidad del Norte, Colombia

About: Universidad del Norte, Colombia is a education organization based out in Barranquilla, Colombia. It is known for research contribution in the topics: Population & Context (language use). The organization has 3562 authors who have published 4355 publications receiving 37861 citations. The organization is also known as: University of the North, Colombia & Uninorte.

Spatio-temporal variations of sulfur dioxide concentrations in industrial and urban area via a new statistical approach

Abstract: Sulfur dioxide (SO2) is considered the most widespread pollutant that threatens environmental and human health. The purpose of this study is to propose a new method for evaluating the spatial variation of SO2 levels in the Metropolitan Area of Porto Alegre (MAPA). This method included use of Chi-square test to better identify the origin of SO2 sources. Additionally, results of the different methods applied allowed to analyze the temporal SO2 levels and their association with meteorological parameters. SO2 at five sampling sites (Esteio, Canoas, Charqueadas, Triunfo, and Gravatai) were measured during 2010–2015; using fluorescence SO2 automated analyzers. Results showed that Charqueadas had the highest average concentration (~ 15 μg m−3), followed by Triunfo (13 μg m−3), Esteio (6 μg m−3), Canoas (3 μg m−3), and Gravatai (2 μg m−3). Chi-square test applied to SO2, and wind direction quadrants showed significant contribution of local emission sources. Seasonal variation revealed higher SO2 levels on cold days for most of the studied sites, except for Esteio site. Day-wise variations revealed higher SO2 concentration on weekdays than weekends for Esteio and Canoas sites, indicating traffic influence especially during the rush-hours. Annual averages analysis identified an increasing trend in SO2 concentrations, implying that applied emission control systems and technological improvement of engines and fuels were not sufficient and thus points out a need for better subsidies mechanisms to pollutant control and effective emission reduction strategies that decision makers, including environmental agencies, must make priority by considering the local realities.

Comportamientos de riesgo para la salud en estudiantes colombianos recién ingresados a una universidad privada en Barranquilla (Colombia)

Abstract: Objective: To investigate the health knowledge and behaviors of first year college students attending a private university in Colombia. Materials and methods: This descriptive study had a sample population of 540 students randomly selected from 2500 eligible students in the population. Data were collected using a modified version of the Youth Risk Behavior Survey developed by the Centers for Disease Control and Prevention in the US. Data were analyzed using SPSS v. 13. Findings. The average age in the sample was 18 years of age, 52.7% of the sample population were women, 13.5% were considered overweight and 2.6% were obese. 20% of the sample walks more than 10 minutes per day, and an additional 20% walks less than 30 minutes on a daily basis. Forty three percent listens to music as a stress management technique. Over two thirds of the study participants have consumed alcohol at least once in their lifestyle, 35.2% have smoked, 56% use some form of contraceptive methods, and 51.1% reported being sexually active. Only 1.1% of study participantsreported an STI, 4.3% had considered suicide in the last year, and 65,2% had actually tried to commit suicide. Conclusions: Risk behaviors are prevalent among first year collage students making important to design strategies designed to ameliorate their influence in the health status of adolescents.

海水中のppbオーダーのクロム(VI)の溶媒抽出濃縮-原子吸光定量

Abstract: クロム(III)の共存する海水中の微量クロム(VI)を定量するため,クロム(VI)をジエチルジチオカルバミン酸塩としてメチルイソブチルケトンに溶媒抽出し,アセチレン-空気フレームあるいは黒鉛炉による原子吸光法で測定する方法を提案した.クロム(VI)の抽出はpH5で最大であるが,クロム(III)の影響がないpH4で抽出した.最適のジエチルジチオカルバミン酸ナトリウム濃度は,水相中のクロム(VI)濃度0.5ppmについて2.0×10-3Mである.水相の容量を100,200,300,500及び1000ml,有機相の容量を10,15,15,20及び30mlとした場合,いずれも直線の検量線が得られ,水相の容量が多くなると感度はほぼ直線的に向上することが分かった.水相と有機相の容量が1000mlと30mlの場合の感度は,フレーム法で1%吸収当たり0.4ppbのクロム,フレームレス法で0,02ppbである.10ppmのストロンチウム(II),1ppmのバリウム(II),10ppbの銅(II),鉛(II),亜鉛(II),カドミウム(II),水銀(II),ニッケル(II),ヒ素(III),マンガン(II),コバルト(III),ベリリウム(II),アルミニウム(III),鉄(III),モリブデン(VI)の共存は,1.0ppbのクロム(VI)の定量を妨害しない,本法で合成海水及び数種海水試料中のクロム(VI)を定量した.更に海水試料に一定量のクロム(VI)を添加し,クロム(VI)を定量したところ,満足すべき回収率が得られた.

Tolerance of Homosexuality in South American Countries: A Multilevel Analysis of Related Individual and Sociocultural Factors

Abstract: Objectives: This study examines the effect of some factors at individual and aggregated level on tolerance of homosexuality (TOH) in some South American countries. Method: The study performs a mult...