688 research outputs found

    Predicción de la frescura del aceite de oliva virgen extra durante el almacenamiento mediante espectroscopía de fluorescencia

    Get PDF
    Virgin olive oil quality relates to flavor and unique health benefits. Some of these properties are at the most desirable level when the oil is just extracted, since it is not a product that improves with age. On the contrary, the concentrations of many compounds change during its shelf-life. These changes reveal the aging of the oil but do not necessarily mean decay in sensory properties, so in some cases an aged oil from healthy olives may be better qualified than a fresh one from olives affected by fermentation. The aim of this work is to analyze different methodologies proposed for assessing the quality of virgin olive oil with implications in freshness and aging of the oil, and to highlight the possibilities of rapid spectrofluorimetric techniques for assessing oil freshness by checking the evolution of pigments during storage. The observed change in the selected spectral features and mathematical modelling over time was compared with the accepted model for predicting the amount of pyropheophytin a, which is based on isokinetic studies. The best regression was obtained for 655 nm (adjustedR2 = 0.91) wavelength, which matches the distinctive band of pigments. The two mathematical models described in this study highlight the usefulness of pigments in the prediction of the shelf-life of extra virgin olive oil.La calidad del aceite de oliva virgen está relacionada con su flavor y sus beneficios únicos para la salud. Algunas de estas propiedades se encuentran en el nivel más deseable cuando el aceite está recién extraído, ya que no es un producto que mejore con el tiempo. Por el contrario, las concentraciones de muchos compuestos cambian a lo largo de la vida útil. Estos cambios revelan el envejecimiento del aceite, pero no implican necesariamente la alteración de las propiedades sensoriales, por lo que en algunos casos un aceite envejecido procedente de aceitunas sanas puede presentar mejor calidad que uno fresco procedente de aceitunas afectadas por procesos de fermentación. El objetivo de este trabajo es estudiar diferentes metodologías propuestas para evaluar la calidad del aceite de oliva virgen con implicaciones en la frescura y el envejecimiento del aceite, destacando las posibilidades de las rápidas técnicas espectrofluorométricas para evaluar la frescura del aceite verificando la evolución de los pigmentos durante el almacenamiento. El cambio observado en las características espectrales seleccionadas y su modelado matemático a lo largo del tiempo se comparó con el modelo aceptado para predecir la cantidad de pirofeofitina a, que se basa en estudios isocinéticos. Los dos modelos matemáticos descritos en este estudio pusieron de manifiesto la utilidad de los pigmentos en la predicción de la vida útil del aceite de oliva virgen extra. La mejor regresión se obtuvo para 655 nm (R2 -ajustado = 0,91), longitud de onda que coincide con la banda distintiva de pigmentos.Secretaría de Estado de Investigación, Desarrollo e Innovación de España-AGL2015-69320-

    Predicción de la frescura del aceite de oliva virgen extra durante el almacenamiento mediante espectroscopía de fluorescencia

    Get PDF
    Virgin olive oil quality relates to flavor and unique health benefits. Some of these properties are at the most desirable level when the oil is just extracted, since it is not a product that improves with age. On the contrary, the concentrations of many compounds change during its shelf-life. These changes reveal the aging of the oil but do not necessarily mean decay in sensory properties, so in some cases an aged oil from healthy olives may be better qualified than a fresh one from olives affected by fermentation. The aim of this work is to analyze different methodologies proposed for assessing the quality of virgin olive oil with implications in freshness and aging of the oil, and to highlight the possibilities of rapid spectrofluorimetric techniques for assessing oil freshness by checking the evolution of pigments during storage. The observed change in the selected spectral features and mathematical modelling over time was compared with the accepted model for predicting the amount of pyropheophytin a, which is based on isokinetic studies. The best regression was obtained for 655 nm (adjustedR2 = 0.91) wavelength, which matches the distinctive band of pigments. The two mathematical models described in this study highlight the usefulness of pigments in the prediction of the shelf-life of extra virgin olive oil.La calidad del aceite de oliva virgen está relacionada con su flavor y sus beneficios únicos para la salud. Algunas de estas propiedades se encuentran en el nivel más deseable cuando el aceite está recién extraído, ya que no es un producto que mejore con el tiempo. Por el contrario, las concentraciones de muchos compuestos cambian a lo largo de la vida útil. Estos cambios revelan el envejecimiento del aceite, pero no implican necesariamente la alteración de las propiedades sensoriales, por lo que en algunos casos un aceite envejecido procedente de aceitunas sanas puede presentar mejor calidad que uno fresco procedente de aceitunas afectadas por procesos de fermentación. El objetivo de este trabajo es estudiar diferentes metodologías propuestas para evaluar la calidad del aceite de oliva virgen con implicaciones en la frescura y el envejecimiento del aceite, destacando las posibilidades de las rápidas técnicas espectrofluorométricas para evaluar la frescura del aceite verificando la evolución de los pigmentos durante el almacenamiento. El cambio observado en las características espectrales seleccionadas y su modelado matemático a lo largo del tiempo se comparó con el modelo aceptado para predecir la cantidad de pirofeofitina a, que se basa en estudios isocinéticos. Los dos modelos matemáticos descritos en este estudio pusieron de manifiesto la utilidad de los pigmentos en la predicción de la vida útil del aceite de oliva virgen extra. La mejor regresión se obtuvo para 655 nm (R2 -ajustado = 0,91), longitud de onda que coincide con la banda distintiva de pigmentos.Secretaría de Estado de Investigación, Desarrollo e Innovación de España-AGL2015-69320-

    Low temperature pyrolysis of thin film composite polyphosphazene membranes for hot gas separation

    Get PDF
    Highly selective thin-film composite membranes for hot hydrogen sieving are prepared via the pyrolysis of thin cyclomatric polyphenoxy phosphazene films that are prepared via a non-conventional interfacial polymerization of hexachlorocyclotriphosphazene with 1,3,5-trihydroxybenzene or m-dihydroxybenzene. The presence of the cyclic phosphazene ring within the weakly branched polymer films gives rise to a distinct thermal degradation evolution, with an onset temperature of around 200 °C. For the trihydroxybenzene derived material, the hydrogen permselectivity of the films shows a maximum pyrolysis temperature of around 450 °C. At this temperature a compact atomic structure is obtained that comprises mostly disordered carbon and accommodates P–O–C and P–O–P bonds. During thermal treatment, these films reveal molecular sieving with permselectivities exceeding 100 for H2/N2, H2/CH4, and H2/CO2, and a hydrogen permeance of 2 × 10−10 to 1.5 × 10−8 mol/m2/s/Pa (0.6-44.8GPU), at 200 °C. At ambient temperatures, thin films are very effective barriers for small gas molecules. Because of the inexpensive facile synthesis and low- temperature pyrolysis, the polyphosphazene films have the potential for use in high-temperature industrial gas separations, as well as for use as barriers such as liners in high- pressure hydrogen storage vessels at ambient temperature.</p

    Utilization of muddy detritus as organic matter source by the fan mussel Pinna nobilis.

    Get PDF
    The knowledge of the feeding habits in marine species is fundamental to better understand their relationship with the environment. Although phytoplankton has been traditionally reported as the main food source consumed by the Mediterranean fan mussel Pinna nobilis, recent studies have revealed that detritus represents an important food source for this species. We analysed the degree of acceptance of muddy detritus and the utilisation of its organic matter (OM) by P. nobilis on a group of 21 individuals (30.3-59.7 cm of total shell height (Ht)). The specimens were collected between July and September 2012 in two areas (43°04´25” N; 5°46´7” E and 43°04´34” N; 5°47´32” E) of the Embiez archipelago, northwestern Mediterranean (France). Our studies show that P. nobilis retains high quantities of OM from muddy detritus (47.50 ± 11.23% of filtered OM) irrespectively of shell size. Smaller individuals, however, actively filter more detritus than large ones. The values of retained OM, together with previous studies on stomach contents, suggest that muddy detritus is a more important OM source than phytoplankton for this species

    Predicción de la frescura del aceite de oliva virgen extra durante el almacenamiento mediante espectroscopía de fluorescencia

    Get PDF
    Virgin olive oil quality relates to flavor and unique health benefits. Some of these properties are at the most desirable level when the oil is just extracted, since it is not a product that improves with age. On the contrary, the concentrations of many compounds change during its shelf-life. These changes reveal the aging of the oil but do not necessarily mean decay in sensory properties, so in some cases an aged oil from healthy olives may be better qualified than a fresh one from olives affected by fermentation. The aim of this work is to analyze different methodologies proposed for assessing the quality of virgin olive oil with implications in freshness and aging of the oil, and to highlight the possibilities of rapid spectrofluorimetric techniques for assessing oil freshness by checking the evolution of pigments during storage. The observed change in the selected spectral features and mathematical modelling over time was compared with the accepted model for predicting the amount of pyropheophytin a, which is based on isokinetic studies. The best regression was obtained for 655 nm (adjusted-R2 = 0.91) wavelength, which matches the distinctive band of pigments. The two mathematical models described in this study highlight the usefulness of pigments in the prediction of the shelf-life of extra virgin olive oil.La calidad del aceite de oliva virgen está relacionada con su flavor y sus beneficios únicos para la salud. Algunas de estas propiedades se encuentran en el nivel más deseable cuando el aceite está recién extraído, ya que no es un producto que mejore con el tiempo. Por el contrario, las concentraciones de muchos compuestos cambian a lo largo de la vida útil. Estos cambios revelan el envejecimiento del aceite, pero no implican necesariamente la alteración de las propiedades sensoriales, por lo que en algunos casos un aceite envejecido procedente de aceitunas sanas puede presentar mejor calidad que uno fresco procedente de aceitunas afectadas por procesos de fermentación. El objetivo de este trabajo es estudiar diferentes metodologías propuestas para evaluar la calidad del aceite de oliva virgen con implicaciones en la frescura y el envejecimiento del aceite, destacando las posibilidades de las rápidas técnicas espectrofluorométricas para evaluar la frescura del aceite verificando la evolución de los pigmentos durante el almacenamiento. El cambio observado en las características espectrales seleccionadas y su modelado matemático a lo largo del tiempo se comparó con el modelo aceptado para predecir la cantidad de pirofeofitina a, que se basa en estudios isocinéticos. Los dos modelos matemáticos descritos en este estudio pusieron de manifiesto la utilidad de los pigmentos en la predicción de la vida útil del aceite de oliva virgen extra. La mejor regresión se obtuvo para 655 nm (R2-ajustado = 0,91), longitud de onda que coincide con la banda distintiva de pigmentos

    Rancang Bangun Sistem Pengenalan Wajah Daftar Pencarian Orang (Dpo) Berbasis Jaringan Saraf Tiruan

    Full text link
    This study aims to design a system that is able to recognize the face of a people search list (DPO). The application is built using opencv and dlib ddan system testing is done with a dataset consisting of 6 target people. The target was identified when it was exactly perpendicular to the camera but the detection failed when the target\u27s face was not exactly perpendicular. This study also models the transmission of target data detected using long range radio (LORA) at a frequency of 91

    Localized versus delocalized states: Photoluminescence from electrochemically synthesized ZnO nanowires

    Get PDF
    We analyze the near-band-edge photoluminescence of electrochemically deposited ZnO nanowires and directly correlate the photoluminescence properties with the carrier concentration in the nanowires as determined from electrochemical impedance spectroscopy. We find a donor density of 81019 cm−3 in the as-deposited nanowires and show that the near-band-edge emission results from band-to-band recombination processes delocalized states. A photoluminescence band centered at 3.328 eV scales with the diameter of the nanowires and is assigned to recombination processes involving surface states. We show that annealing at 500 °C in air reduces the donor density in the nanowires by more than one order of magnitude, leading to sharp excitonic transitions in the electrochemically deposited nanowire

    Simultaneous Culture and Biomachining of Copper in MAC Medium: A Comparison between Acidithiobacillus ferrooxidans and Sulfobacillus thermosulfidooxidans

    Get PDF
    Biomachining will not be considered as a full-scale manufacturing technology until a stable, controlled, and continuous metal removal rate (MRR) is achieved. In this research work, a novel strategy that could promote its industrial implementation, namely simultaneous bacterial growth and machining of copper contained in oxygen-free copper (OFC) workpieces, was investigated. This proposal has the major advantage of being a single-stage process, thereby reducing total operating times and becoming more economical in comparison with conventional biomachining (downtime due to bacterial growth would disappear). The study was carried out using mesophilic (Acidithiobacillus ferrooxidans) and thermophilic (Sulfobacillus thermosulfidooxidans) extremophile bacteria in order to prevent the progressive decrease in the amount of metal removed per unit time. A constant MRR of 43 mg h-1 was achieved with A. ferrooxidans in the simultaneous process. Despite the accomplishment of a constant MRR, this value is lower than the maximum MRR obtained in conventional biomachining (109 mg h-1), probably due to the inability of ferric ions to come into contact with the metallic surface. With regard to the culture period in MAC medium, S. thermosulfidooxidans showed a slower growth rate (0.11 h-1) and lower ferrous ion oxidation level (0.12 g Fe2+ L-1 h-1) than A. ferrooxidans (0.17 h-1 and 0.22 g Fe2+ L-1 h-1, respectively) under optimal pH (1.5) and Fe2+ concentration (6 g L-1) conditions.Fil: Diaz Tena, E.. Universidad del País Vasco; España. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; ArgentinaFil: Gallastegui, G.. Universidad del País Vasco; EspañaFil: Hipperdinger, Marcela Liliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; ArgentinaFil: Donati, Edgardo Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Fermentaciones Industriales. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Fermentaciones Industriales; ArgentinaFil: Rojo, N.. Universidad del País Vasco; EspañaFil: Santaolalla, A.. Universidad del País Vasco; EspañaFil: Ramirez, M.. Universidad del País Vasco; EspañaFil: Barona, A.. Universidad de Cádiz; EspañaFil: Elías, A.. Universidad del Pais Vasco - Euskal Herriko Unibertsitatea, Campus Bizkaia

    GAMBARAN ASUPAN ZAT GIZI MAKRO DAN PROSES ASUHAN GIZI PADA PASIEN JANTUNG KORONER DI RSUD PROF D.R W.Z. YOHANES KUPANG

    Get PDF
    The prevalence of 2.4 percent is above the national prevalence which is 1.5 percent. The prevalence of coronary heart disease aged 15 years according to East Nusa Tenggara Province, Riskesdas 2013 in Kupang city, was 0.3%. Total patients from January – 23 May 2022 inpatients at Prof. W.Z. Johanes Hospital Kupang as many as 4 patients suffering from coronary heart disease (CHD). Dr. W. Z. Johanes Kupang. Research Methods The method used is a case study research design using observational case studies. Research Results Based on the results of monitoring the food intake of the 3 respondents for 2 days of recall with hospital food consumption, the results for the first respondent were 61.17% of energy intake in the category deficit, the percent of protein intake is 80.42% in the sufficient category, the percent of fat intake is 34.43% in the deficit category, and the percent of carbohydrate intake is 67.24% in the deficit category. For the second respondent, the percent of energy intake is 64.64% in the deficit category, the percent of protein intake is 82.69% in the sufficient category, the percent of fat intake is 29.0% in the deficit category, and carbohydrate intake is 71.32% in the less category. As for the third respondent, the percent of energy intake is 56.04% in the deficit category, the percent of protein intake is 33.65% in the deficit category, the percent of fat intake is 71.01% in the less category, and the percent of carbohydrate intake is 61.6 in the category deficit.  Prevalensi sebesar 2,4 persen tersebut berada diatas prevalensi nasionl yang besarnya 1,5 persen Prevalensi penyakit jantung koroner umur ≥ 15 tahun menurut Provinsi Nusa Tenggara Timur, Riskesdas 2013 di kota kupang, sebesar 0,3%.Total pasien dari bulan Januari – 23 Mei tahun 2022 pasienrawatinap diRSUD Prof.W.Z.Johanes Kupang sebanyak 4 pasien yang menderita penyakit jantung koroner(PJK).Tujuan Penelitian Mengetahui asupan zat gizi mikri dan asuhan gizi pada pasien jantung koroner(PJK) diruang rawat inap RSUD Prof. Dr. W. Z. Johanes Kupang.  Metode yang digunakan ialah desain penelitian studi kasus dengan menggunakan studi kasus observasional Hasil Penelitian Berdasarkan hasil monitoring asupan makan  ke-3 responden selama 2 hari recall dengan konsumsi makanan rumah sakit diperoleh hasil untuk reponden pertama persen asupan energy yakni 61,17% dengan kategori deficit, persen asupan protein yakni 80,42% dengan kategori cukup, persen asupan lemak yakni 34,43% dengan kategori deficit, dan persen asupan karbohidrat yakni 67,24% dengan kategori deficit. Untuk responden kedua persen asupan energy yakni 64,64% dengan kategori deficit, persen asupan protein yakni 82,69% dengan kategori cukup, persen asupan lemak yakni 29,0% dengankategori deficit, dan persen asupan karbohirat yakni 71,32% dengan kategori kurang. Sedangkan untuk responden ketiga persen asupan energy yakni 56,04% dengan kategori deficit, persen asupan protein yakni 33,65% dengan kategori deficit, persen asupan lemak yakni 71,01% dengan kategori kurang, dan persen asupan karbohidrat yakni 61,6 dengan kategori deficit.  
    corecore