Use of a new enrichment nanosorbent for speciation of mercury by FI-CV-ICP-MS

Mercury is one of the most toxic environmental pollutants and its effects on human and ecosystem health are well known. All mercury species are toxic, with organic mercury compounds generally being more toxic than inorganic species. Chromatography techniques (GC, HPLC) coupled to element specific detectors, are able to separate mercury species in order to elucidate mercury transformation and transport processes where the determination of all mercury species is desirable. However, in practice, especially in sampling campaigns for sea water analysis where a large number of samples are collected over a longer period of time, a combination of methods is usually applied to accurately determine the most toxic mercury species. These include non-chromatographic methods based on the different chemical and/or physical behavior of the mercury species. These non-chromatographic methods can be less time consuming, more cost effective and available, and present competitive limits of detection. Especially when mercury could vapor (CV) generation technique is employed, which reduces salt effect on the analytical signal and improve the sensibility. Among non-chromatographic methods, solid phase extraction and microextraction (SPE and SPME) which is becoming increasingly popular for sample preparation in organic analysis, found its way to speciation analysis of organometals. SPE/SPME is the most popular sample preconcentration method for its simplicity, high enrichment factor, low or no consumption of organic solvents and feasibly to be automated. On the other hand, the exploration of new materials, especially nanometer sized materials, as the support phase is another active research area in SPE/SPME for mercury determination. The use of nanoparticles leads to higher extraction capacity/efficiency and rapid dynamics of extraction originated from the higher surface area to volume ratio and short diffusion route. In this work, a new enrichment nanosorbent functionalized with 1,5 bis (2-pyridyl) methylene thiocarbohidrazide was synthesized and characterized. From the study of its adsorption capacity toward metal ions, Hg2+ was observed to be one of the most retained 173.1 µmol g-1 at pH 5. Thus, a flow injection solid phase extraction and cold vapor generation method for its determination and speciation based on the use of this new chelating nanosorbent was optimized. The method developed has showed to be useful for the automatic pre-concentration and sequential speciation of mercury and methylmercury in environmental and biological samples. The system was based on chelating retention of the analytes onto a mini-column filled with the new nanosorbent and their sequential elution by using two different eluents, 0.2 % HCl for CH3Hg+ and 0.1 % thiourea in 0.5 % HCl for Hg2+. The determination was performed using inductively coupled plasma mass spectrometry. Under the optimum conditions and 120 s preconcentration time, the enrichment factors were 4.7 and 11.0; the detection limits (3σ) were 0.002 and 0.004 µg L-1; the determination limits (10σ) were 0.011 and 0.024 µg L-1; and the precisions (calculated for 10 replicate determinations at a 2 µg L-1 standard of both species) were 2.8 and 2.6 % (RSD); for CH3Hg+ and Hg2+, respectively. Linear calibration graphs were obtained for both species from the determination limits to at least 70 µg L-1. For the quality control of the analytical performance and the validation of the newly developed method, the analysis of two certified samples, LGC 6016 estuarine water and SRM 2976 mussel tissue were addressed. The results showed good agreement with the certified values. The method was successfully applied to the speciation of mercury in sea-water samples collected in the Málaga Bay.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Nondiffractive sonic crystals

We predict theoretically the nondiffractive propagation of sonic waves in periodic acoustic media (sonic crystals), by expansion into a set of plane waves (Bloch mode expansion), and by finite difference time domain calculations of finite beams. We also give analytical evaluations of the parameters for nondiffractive propagation, as well as the minimum size of the nondiffractively propagating acoustic beams.Comment: 7 figures, submitted to J. Acoust. Soc. A

Influencia de los ácidos grasos poliinsaturados en el modelo de colitis ulcerosa experimental inducida por ácido-2,4,6-trinitrobencenosulfónico: estudio histoquímico y estructural

La administración intrarrectal de ácido 2,4,6 trinitrobencenosulfónico (TNBS) en animales de experimentación induce el desarrollo de la colitis ulcerosa, resultando en alteraciones histológicas a nivel de la mucosa intestinal y la producción de inflamación, así demostrada por un incremento en la actividad de la mieloperoxidasa. Este estudio evalúa la influencia de diferentes dietas suplementadas con ácidos grasos mono- y poliinsaturados sobre el grado de recuperación estructural tras el daño inducido por TNBS, así como sobre el porcentaje de células caliciformes y el grado de maduración de la mucina producida por estas células. Los cambios en las mucinas intestinales están directamente unidos a un equilibrio dinámico entre su biosíntesis por parte de las células caliciformes y su degradación dentro del lumen intestinal, por ello es pertinente cuantificar los efectos de la dieta sobre la síntesis y la secreción de glicoproteínas neutras, ácidas y sulfatadas. La composición de la dieta tal como hemos demostramos en este trabajo, influye en la arquitectura de la mucosa intestinal y en el modelo de secreción de las mucinas. De acuerdo con nuestros datos, la suplementación de la dieta con aceites de oliva (n-9) y de pescado (n-3) parece tener un papel protector en la inflamación de la colitis ulcerosa

WANPRESTASI DALAM PERJANJIAN ONLINE ANTARA ENDORSER DENGAN PEMILIK BISNIS ONLINE MELALUI INSTAGRAM DIHUBUNGKAN DENGAN KUHPERDATA DAN UNDANG-UNDANG NOMOR 11 TAHUN 2008 TENTANG INFORMASI DAN TRANSAKSI ELEKTRONIK

Dilatarbelakangi Perkembangan teknologi dan informasi yang semakin pesat pada era saat ini. Lahirlah perjanjian online melalui instagram yang dilakukan antara selebgram Gina Meidina Putri di bawah akun @ginameidinaa sebagai Selebgram dan Ananda Zein sebagai Pemilik bisnis online di bawah akun @myrubylicious yang bergerak dalam bisnis pakaian. Namun perjanjian online antara Gina sebagai selebgram dan Ananda sebagai pemilik bisnis online tidak berjalan dengan lancar, karena selebgram tidak memenuhi prestasi sesuai dengan perjanjian yang telah disepakati. Dari hal tersebut, maka perlu dikaji, mengenai bagaimana terjadinya wanprestasi yang dilakukan oleh selebgram terhadap pemilik bisnis online melalui Instagram, akibat hukum selebgram yang melakukan wanprestasi terhadap pemilik bisnis online melalui Instagram dihubungkan dengan KUHPerdata dan Undang-Undang No 11 Tahun 2008 tentang Informasi dan Transaksi Elektronik, dan penyelesaian wanprestasi yang dilakukan oleh selebgram terhadap pemilik bisnis online melalui Instagram. Penelitian ini bersifat deskriptif-analitis, yaitu menggambarkan secara menyeluruh dan sistematis tentang wanprestasi dalam perjanjian online antara Endorser dengan Pemilik Bisnis Online melalui Instagram. Metode pendekatan yang digunakan dalam penelitian ini adalah yuridis-normatif, yaitu metode yang bertujuan mencari asas, kaidah, dan norma atau das sollen dan perilaku atau das sein. Tahap penelitian meliputi penelitian kepustakaan, yakni penelitian yang dimaksudkan untuk mendapatkan data sekunder dan penelitian lapangan, yakni suatu cara untuk memperoleh data primer sebagai pendukung data sekunder. Teknik pengumpulan data, meliputi studi dokumen yakni data yang diteliti dalam suatu penelitian yang diperoleh melalui bahan kepustakaan, dan wawancara yakni cara untuk memperoleh informasi dengan bertanya langsung kepada yang diwawancarai. Alat pengumpul data dalam penelitian kepustakaan berupa catatan hasil intentarisasi bahan hukum dan alat pengumpul data dalam penelitian lapangan berupa daftar pertanyaan, handphone, email dan flashdisk. Analisis data menggunakan metode yuridis-kualitatif, yaitu menganalisis data sekunder dan data primer yang dianalisis tanpa rumus matematika. Hasil penelitian menunjukan, bahwa wanprestasi yang terjadi dikarenakan selebbgram terlambat melakukan prestasi terhadap pemilik bisnis online yang mengakibatkan kerugian materil atau menghilangkan keuntungan. Akibat hukum dari selebgram yang melakukan wanprestasi terhadap pemilik bisnis online melalui Instagram meminta pemenuhan prestasi berdasarkan Pasal 1267 dan Pasal 1243 KUHPerdata dan Pasal 38 ayat (1) UU ITE mengatur bahwa tidak dipenuhi prestasinya dapat diajukan gugatan. Penyelesaian wanprestasi yang dilakukan oleh selebgram terhadap pemilik bisnis online melalui Instagram adalah berdasarkan penyelesaian sengketa melalui cara-cara alternatif. Kata Kunci : Wanprestasi, Perjanjian Onlin

Development of an autonomous subersible profiler with the ability to stop at specific depths for measurement of marine parameters

Understanding marine pollution problems is a complex topic that has led to a wide range of research over the last decades. In this research, an autonomous submersible profiler with controlled depth detention for the measurement of parameters of interest in shallow marine environments -is presented. The device has been designed to carry on several sensors including dissolved oxygen, chlorophyll, electrical conductivity and temperature among others. The profiler includes the performance for sampling, collecting and wireless sending reliable real-time data in marine environments. In addition, its ability to stop at a given depth allows for more accurate and stable measurement of marine parameters at different depth levels. This research describes the design of the profiler as well as the different control assumptions made to achieve zero buoyancy at a given depth. The results show that the submersible profiler is a valuable tool for continuous monitoring of marine parameters relevant to study the causes leading to critical environmental situations.Peer Reviewe

Identificación de los problemas económicos de las mipymes del sector Muebles para el Hogar del municipio de Palmira Valle, y su acceso a las fuentes de financiación

Las Mipymes se han convertido en el ámbito socioeconómico en un sostén que fortalece la economía del país y en una fuente importante de generación de empleo que abarca la gran mayoría de sectores económicos. Las Mipymes representan más del 90% de establecimientos, más del 50% del empleo nacional, más del 40% de la producción manufacturera nacional, el 40% de los salarios, y el 70% de los principales centros productivos nacionales, en lugares de Colombia como Bogotá y Cundinamarca, Antioquía, Atlántico y el Valle del Cauca. Las Mipymes se encuentran en los principales sectores, en el COMERCIO con un 58% donde encontramos compañías tales como los Alimentos, los textiles, los muebles, las confecciones textiles, los SERVICIOS con un 30% de participación y en la INDUSTRIA con un 12%, donde se encuentran empresas de Alimentos, cuero/calzado, muebles/madera, textil/confecciones, artes gráficas, plásticos, químicos, metalurgia/metalmecánica, autopartes, minerales no metálicos. Pero la desaceleración de la economía nacional, departamental y municipal ha repercutido de manera directa en las Mipymes del sector de los muebles para el hogar elaborados en madera generando problemas económicos dentro de éstas, además de los ya existentes dentro de sus empresas.PregradoCONTADOR(A) PÚBLIC

Induced Magnetic Anisotropy in Liquid Crystals Doped with Resonant Semiconductor Nanoparticles

Currently, there are many efforts to improve the electrooptical properties of liquid crystals by means of doping them with different types of nanoparticles. In addition, liquid crystals may be used as active media to dynamically control other interesting phenomena, such as light scattering resonances. In this sense, mixtures of resonant nanoparticles hosted in a liquid crystal could be a potential metamaterial with interesting properties. In this work, the artificial magnetism induced in a mixture of semiconductor nanoparticles surrounded by a liquid crystal is analyzed. Effective magnetic permeability of mixtures has been obtained using the Maxwell-Garnett effective medium theory. Furthermore, permeability variations with nanoparticles size and their concentration in the liquid crystal, as well as the magnetic anisotropy, have been studied

Análisis del comportamiento emocional en alumnos de psicopedagogía

Con esta investigación queremos poner de manifiesto que el conocimiento de las emociones y el trabajar con ellas son aspectos básicos en el marco educativo actual. En el presente estudio nos planteamos: conocer, evaluar y analizar los niveles emocionales en las dimensiones de la escala TMMS de Inteligencia Emocional, es decir, Atención, Claridad y Reparación emocional. Analizamos estas dimensiones emocionales en los futuros psicopedagogos de la Facultad de Educación en Extremadura.With this investigation we want to reveal that the knowledge of the emotions and to work with them are basic aspects in the educational current frame. In the present study we appear: to know, to evaluate and to analyze the emotional levels in the dimensions of the scale TMMS of Emotional Intelligence: Attention, Clarity and emotional Repair. We analyze these emotional dimensions in the future educational psychologists of the Faculty of Education in Extremadura.peerReviewe

Aplicación de las nuevas tecnologías a la enseñanza de la Geología en la E.T.S.I. Minas de Madrid

En este trabajo se presentan nuevas estrategias y metodologías de enseñanza y aprendizaje, y tareas de los estudiantes implementadas en asignaturas relacionadas con la Geología de la E.T.S.I. Minas de Madrid. El principal objetivo es acercar los aspectos geológicos de la Naturaleza (Geología) a los estudiantes mediante el empleo de nuevas tecnologías, empleando técnicas individuales y grupales. Se ha observado una mayor motivación y adquisición de conocimientos geológicos por parte del alumnado, que ha llevado aparejado una mejora en las calificaciones

Stimulatory Response of Celiac Disease Peripheral Blood Mononuclear Cells Induced by RNAi Wheat Lines Differing in Grain Protein Composition

Wheat gluten proteins are responsible for the bread-making properties of the dough but also for triggering important gastrointestinal disorders. Celiac disease (CD) affects approximately 1% of the population in Western countries. The only treatment available is the strict avoidance of gluten in the diet. Interference RNA (RNAi) is an excellent approach for the down-regulation of genes coding for immunogenic proteins related to celiac disease, providing an alternative for the development of cereals suitable for CD patients. In the present work, we report a comparative study of the stimulatory capacity of seven low-gluten RNAi lines differing in grain gluten and non-gluten protein composition, relevant for CD and other gluten pathologies. Peripheral blood mononuclear cells (PBMCs) of 35 patients with active CD were included in this study to assess the stimulatory response induced by protein extracts from the RNAi lines. Analysis of the proliferative response and interferon-gamma (INF-γ) release of PBMCs demonstrated impaired stimulation in response to all RNAi lines. The lower response was provided by lines with a very low content of α- and γ-gliadins, and low or almost devoid of DQ2.5 and p31–43 α-gliadin epitopes. The non-gluten protein seems not to play a key role in PBMC stimulation.Spanish Ministry of Economy, Industry and competitiveness AGL2016-80566-PEuropean Regional Development Fund (FEDER