Study and Analysis of Semiconductors for the Development of Two-layer Solar Cells

Jefry Mora,Jorge Ospina,Darío Amaya 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.11

In the field of renewable energies, researchers have always looked for the improvement of the conversion method in solar cells, due to the fact that only 14% of the electrical potential is being used. That is why in order to increase efficiency, different designs and materials have been studied. One of the most viable ways is the technology of multilayer solar cells, which the recent investigations focused due to the fact this technique allows the possibility of achieving efficiencies above 30%. Despite the above, the problem of this technique is the cost of manufacturing, which compared to the commercial cells, is inferior in benefit - cost relationship. For this reason, this paper shows a study of different semiconductors to design a two-layer solar cell, with the aim of selecting the best combination of semiconductors according to their own characteristics and results according to the described method.

Prediction of tenderness in bovine longissimus thoracis et lumborum muscles using Raman spectroscopy

Coria Maria Sumampa,Castaño Ledesma María Sofía,Gómez Rojas Jorge Raúl,Grigioni Gabriela,Palma Gustavo Adolfo,Borsarelli Claudio Darío 아세아·태평양축산학회 2023 Animal Bioscience Vol.36 No.9

Objective: This study was conducted to evaluate Raman spectroscopy technique as a noninvasive tool to predict meat quality traits on Braford longissimus thoracis et lumborum muscle. Methods: Thirty samples of muscle from Braford steers were analyzed by classical meat quality techniques and by Raman spectroscopy with 785 nm laser excitation. Water holding capacity (WHC), intramuscular fat content (IMF), cooking loss (CL), and texture profile analysis recording hardness, cohesiveness, and chewiness were determined, along with fiber diameter and sarcomere length by scanning electron microscopy. Warner-Bratzler shear force (WBSF) analysis was used to differentiate tender and tough meat groups. Results: Higher values of cohesiveness and CL, together with lower values of WHC, IMF, and shorter sarcomere were obtained for tender meat samples than for the tougher ones. Raman spectra analysis allows tender and tough sample differentiation. The correlation between the quality attributes predicted by Raman and the physical measurements resulted in values of R2 = 0.69 for hardness and 0,58 for WBSF. Pearson's correlation coefficient of hardness (r = 0.84) and WBSF (r = 0.79) parameters with the phenylalanine Raman signal at 1,003 cm–1, suggests that the content of this amino acid could explain the differences between samples. Conclusion: Raman spectroscopy with 785 nm laser excitation is a suitable and accurate technique to identify beef with different quality attributes.

Evaluation of an Active Humidification System for Inspired Gas

Nicolás G. Roux,Gustavo A. Plotnikow,Darío S. Villalba,Emiliano Gogniat,Vivivana Feld,Noelia Ribero Vairo,Marisa Sartore,Mauro Bosso,José L. Scapellato,Dante Intile,Fernando Planells,Diego Noval,Pablo 대한이비인후과학회 2015 Clinical and Experimental Otorhinolaryngology Vol.8 No.1

Objectives. The effectiveness of the active humidification systems (AHS) in patients already weaned from mechanical ventilation and with an artificial airway has not been very well described. The objective of this study was to evaluate the performance of an AHS in chronically tracheostomized and spontaneously breathing patients. Methods. Measurements were quantified at three levels of temperature (Tº) of the AHS: level I, low; level II, middle; and level III, high and at different flow levels (20 to 60 L/minute). Statistical analysis of repeated measurements was performed using analysis of variance and significance was set at a P<0.05. Results. While the lowest temperature setting (level I) did not condition gas to the minimum recommended values for any of the flows that were used, the medium temperature setting (level II) only conditioned gas with flows of 20 and 30 L/minute. Finally, at the highest temperature setting (level III), every flow reached the minimum absolute humidity (AH) recommended of 30 mg/L. Conclusion. According to our results, to obtain appropiate relative humidity, AH and T° of gas one should have a device that maintains water T° at least at 53°C for flows between 20 and 30 L/m, or at T° of 61°C at any flow rate.

Association between cigarette smoking and the prevalence of post-endodontic periapical pathology: a systematic review and meta-analysis

Ríos-Osorio Néstor,Muñoz-Alvear Hernan Darío,Jiménez-Castellanos Fabio Andrés,Quijano-Guauque Sara,Jiménez-Peña Oscar,García-Perdomo Herney Andrés,Caviedes-Bucheli Javier 대한치과보존학회 2022 Restorative Dentistry & Endodontics Vol.47 No.3

Objectives This systematic review and meta-analysis aimed to assess the association of cigarette smoking with the prevalence of post-endodontic apical periodontitis in humans. Materials and Methods We searched through PubMed/Medline, Web of Science, and Scopus from inception to December 2020. Risk of bias was performed by using the Newcastle-Ottawa Scale for cross-sectional, cohort, and case-control studies. We performed the statistical analysis in Review Manager 5.3 (RevMan 5.3). Results 6 studies met the inclusion criteria for qualitative and quantitative synthesis. Statistical analysis of these studies suggests that there were no differences in the prevalence of post endodontic apical periodontitis (AP) when comparing non-smokers vs smoker subjects regarding patients (odds ratio [OR], 0.68; 95% confidence interval [CI], 0.31–1.49; I2 = 58%) and teeth (OR, 1.71; 95% CI, 0.99–2.93; I2 = 72%). Conclusions Our findings suggest that there was no association between cigarette smoking and post-endodontic apical periodontitis, as we did not find statistical differences in the prevalence of post-endodontic AP when comparing non-smokers vs smoker subjects. Therefore, smoking should not be considered a risk factor associated with endodontic failure. Objectives This systematic review and meta-analysis aimed to assess the association of cigarette smoking with the prevalence of post-endodontic apical periodontitis in humans. Materials and Methods We searched through PubMed/Medline, Web of Science, and Scopus from inception to December 2020. Risk of bias was performed by using the Newcastle-Ottawa Scale for cross-sectional, cohort, and case-control studies. We performed the statistical analysis in Review Manager 5.3 (RevMan 5.3). Results 6 studies met the inclusion criteria for qualitative and quantitative synthesis. Statistical analysis of these studies suggests that there were no differences in the prevalence of post endodontic apical periodontitis (AP) when comparing non-smokers vs smoker subjects regarding patients (odds ratio [OR], 0.68; 95% confidence interval [CI], 0.31–1.49; I2 = 58%) and teeth (OR, 1.71; 95% CI, 0.99–2.93; I2 = 72%). Conclusions Our findings suggest that there was no association between cigarette smoking and post-endodontic apical periodontitis, as we did not find statistical differences in the prevalence of post-endodontic AP when comparing non-smokers vs smoker subjects. Therefore, smoking should not be considered a risk factor associated with endodontic failure.

Artificial container mosquitoes and first record of Aedes aegypti in the islands of the Paraná Lower Delta, Argentina

María V. Cardo,Paula Rosín,Aníbal E. Carbajo,Darío Vezzani 한국응용곤충학회 2015 Journal of Asia-Pacific Entomology Vol.18 No.4

Mosquitoes in artificial containers include Aedes aegypti and the Culex pipiens complex, both recognized worldwide as vectors of diseases. The goal of this study was to characterize mosquito communities in water-filled artificial containers in the islands of one of the major temperate wetlands in South America, and to assess whether A. aegypti is present in the area. Five domestic areas located in the insular Tigre District (Buenos Aires Province, Argentina) were visited monthly between November 2011 and May 2012. A total of 1013 artificial containers (half of themwithwater)were inspected formosquito immatures. 3359 specimens corresponding to seven species were collected in 88 containers. A. aegypti was recorded for the first time in this wetland, and in all land use categories examined from February to May. Among the remaining six species, only Culex dolosus and C. pipiens were highly abundant. 88% of themosquito positive containerswere buckets, dustbins and boats,whereas highly available bottles did not act asmosquito breeding habitats; the key breeding containerwas different for each land use. The Container Index showed differences among land uses, materials, water capacity and volume, and insolation levels. Generalized Linear Mixed Models suggested that the probability of finding mosquitoes was higher for containers located in dumps and recreational areas, made of resin/fiberglass, presenting intermediate water volumes, and not in use if partially or totally shaded but in use for sunlit containers. Recommendations formosquito prevention and control in the islands are proposed.

Field efficacy of triflumuron against Aedes and Culex mosquitoes in temperate Argentina

Alejandra Rubio,María V. Cardo,Melania T. Junges,Aníbal E. Carbajo,Darío Vezzani 한국응용곤충학회 2018 Journal of Asia-Pacific Entomology Vol.21 No.1

Aedes aegypti and Culex pipiens s.l. (Linnaeus, 1762 and 1758, respectively) (Diptera: Culicidae) are importantvectors of diseases to humans and a growing public health concern. In order to contribute to the control ofmosquito vectors by low environmental impact approaches we assessed the susceptibility of natural populationsof container-breeding mosquitoes to triflumuron, an insect growth regulator, in temperate Argentina. A field trialwas conducted to evaluate the efficacy of two doses (0.5 ppm and 1 ppm) of triflumuron (SC 48%) againstnatural populations of Ae. aegypti and Culex spp. immatures in flower vases of four cemeteries. The resultsdemonstrated the susceptibility of both target mosquitoes to triflumuron in field conditions. For Ae. aegypti,dose-dependent reductions were achieved in the presence of pupae and the percentage of water-holding containersharbouring L3–4 and/or pupae, whereas the larvae abundance was equally reduced for both doses. ForCulex spp., similar levels of reduction of larvae abundance and pupae presence were achieved with both doses. Significant effects on the response variables measured were recorded up to six to eight weeks post-intervention. Bimonthly applying 1 ppm triflumuron in the context of an integrated mosquito management should achieve alasting control of Ae. aegypti and Culex spp. in small artificial containers with minimal environmental impacts.

Elementos Precinematogr?ficos en El Quijote

Dar?o Villanueva 한국스페인어문학회 2006 스페인어문학 Vol.0 No.41

Desde una temprana aportación del latinista Paul Leglise, estudioso de la Eneida (1958), el concepto de precinema, entendido en una dimensión fundamentalmente estética y artística, se refiere al análisis de las estructuras y recursos formales que se encuentran en los filmes y que aparecen también en obras literarias escritas antes del descubrimiento de los hermanos Lumière. Así, el “arte fílmico”de los escritores cinematográficos consiste en pintar cuadros animados, enriquecerlos mediante todos los artificios de la visión, situarlos según planos diferentes y encadenarlos entre sí conforme a una sintaxis artística que asegure la continuidad de la acción con un ritmo agradable a la imaginación visual del lector. El presente artículo representa una primera aproximación a los elementos precinematográficos presentes en algunos episodios del Quijote de 1605, tales el de la venta en el capítulo XVI, el ataque de don Quijote a los rebaños (capítulo XVIII), el del acuchillamiento de los odres de vino (XXXV) o, entre otros, el de los molinos de viento y la pelea con el vizcaíno (VIII y IX).

Room Temperature Ferrimagnetism and Ferroelectricity in Strained, Thin Films of BiFe _0.5 Mn _0.5 O ₃

Choi, Eun-Mi,Fix, Thomas,Kursumovic, Ahmed,Kinane, Christy J,Arena, Darí,o,Sahonta, Suman-Lata,Bi, Zhenxing,Xiong, Jie,Yan, Li,Lee, Jun-Sik,Wang, Haiyan,Langridge, Sean,Kim, Young-Min,Borisevich John WileySons, Ltd 2014 Advanced Functional Materials Vol.24 No.47

<P>Highly strained films of BiFe<SUB>0.5</SUB>Mn<SUB>0.5</SUB>O<SUB>3</SUB> (BFMO) grown at very low rates by pulsed laser deposition were demonstrated to exhibit both ferrimagnetism and ferroelectricity at room temperature and above. Magnetisation measurements demonstrated ferrimagnetism (<I>T<SUB>C</SUB></I> ∼ 600K), with a room temperature saturation moment (<I>M<SUB>S</SUB></I>) of up to 90 emu/cc (∼ 0.58 <I>μ<SUB>B</SUB></I>/f.u) on high quality (001) SrTiO<SUB>3</SUB>. X-ray magnetic circular dichroism showed that the ferrimagnetism arose from antiferromagnetically coupled Fe<SUP>3+</SUP> and Mn<SUP>3+</SUP>. While scanning transmission electron microscope studies showed there was no long range ordering of Fe and Mn, the magnetic properties were found to be strongly dependent on the strain state in the films. The magnetism is explained to arise from one of three possible mechanisms with Bi polarization playing a key role. A signature of room temperature ferroelectricity in the films was measured by piezoresponse force microscopy and was confirmed using angular dark field scanning transmission electron microscopy. The demonstration of strain induced, high temperature multiferroism is a promising development for future spintronic and memory applications at room temperature and above.</P>

Recent advancements in development and application of microbial cellulose in food and non-food systems

O. P. Shemil Shahaban,Bhosale Yuvraj Khasherao,Rafeeya Shams,Aamir Hussain Dar,Kshirod Kumar Dash 한국식품과학회 2024 Food Science and Biotechnology Vol.33 No.7

Microbial cellulose is a fermented form of very pure cellulose with a fibrous structure. The media rich in glucose or other carbon sources are fermented by bacteria to produce microbial cellulose. The bacteria use the carbon to produce cellulose, which grows as a dense, gel-like mat on the surface of the medium. The product was then collected, cleaned, and reused in various ways. The properties of microbial cellulose, such as water holding capacity, gas permeability, and ability to form a flexible, transparent film make it intriguing for food applications. Non-digestible microbial cellulose has been shown to improve digestive health and may have further advantages. It is also very absorbent, making it a great option for use in wound dressings. The review discusses the generation of microbial cellulose and several potential applications of microbial cellulose in fields including pharmacy, biology, materials research, and the food industry.