6 research outputs found
Structural, Optical, and Morphological Evaluation of Ag-Doped ZnO/CuO/Porous Silicon Heterojunctions for Optoelectronic Applications: Evaluasi Struktur, Optik, dan Morfologi Heterojunctions ZnO/CuO/Silikon Porous yang Doping Ag untuk Aplikasi Optoelektronik
No full textGeneral Background Renewable energy technologies increasingly rely on advanced heterojunction architectures to improve light harvesting and charge transport in optoelectronic devices. Specific Background Multilayer systems combining ZnO, CuO, and porous silicon offer complementary electronic and optical properties, while plasmonic silver incorporation provides additional light–matter interaction pathways. Knowledge Gap However, a systematic experimental correlation between Ag doping concentration, nanostructural evolution, optical behavior, and photovoltaic response in ZnO/CuO/PSi heterojunctions remains insufficiently explored. Aims This study aims to fabricate and evaluate Ag-doped ZnO/CuO/porous silicon heterojunction devices and to examine the role of silver concentration on structural, optical, and electrical characteristics. Results Structural and morphological analyses reveal refined crystallite sizes and pronounced morphology evolution with increasing Ag content, accompanied by enhanced visible-light absorption and bandgap reduction to 2.78 eV at 7% Ag doping. Photovoltaic measurements demonstrate a maximum open-circuit voltage of 3300 mV, a fill factor of 45.09%, and a power conversion efficiency of 0.3125% for the optimized device. Novelty The work provides an integrated experimental assessment linking plasmonic Ag doping to interface engineering and device-level performance within a single heterojunction framework. Implications These findings offer practical guidance for designing cost-effective optoelectronic devices and advancing plasmonic-assisted multilayer solar cell architectures.
Keywords: Ag-doped ZnO, CuO Heterojunction, Porous Silicon, Plasmonic Nanoparticles, Photovoltaic Devices
Key Findings Highlights:
Progressive silver incorporation induces significant morphological and crystallographic modification in multilayer structures.
Visible-light absorption increases markedly due to combined plasmonic and bandgap engineering mechanisms.
Optimized heterojunction configuration exhibits superior voltage output and charge collection behavior
How do latitude and urban heat islands affect monarch butterfly (Danaus plexippus) larval melanisation?
No full textAs temperatures warm in response to anthropogenic changes (climate change and urbanization), animals must respond adaptively to these changes or be displaced. Here, we use community science data (iNaturalist and BugGuide) to show that melanisation in larval monarch butterflies (Danaus plexippus (Linnaeus, 1758)); an endangered species in Canada) is correlated with latitude and temperature across a latitudinal gradient, indicating likely use in thermoregulation. We also predicted that melanisation would decrease in cities where temperatures are consistently higher than rural areas, however we found that while melanisation was lower in urban areas, it was not statistically significant. Our results demonstrate the importance of considering life stage when assessing capacity for adaptation to anthropogenic change in vulnerable animal populations, like monarch butterflies. We also show the value of using community science to sample species (particular those of most concern) distributions across the landscape.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Buffaloes (Bubalus bubalis) mycotic eye infection: reported herd cases in Thi-Qar province, Iraq
No full textOs búfalos são um dos animais de fazenda mais importantes no sul do Iraque e desempenham um papel econômico essencial, atuando principalmente na produção de leite, carne e como animal de tração. Este estudo objetivou diagnosticar infecções oculares micóticas em búfalos na província de Thi-Qar, Iraque. 250 búfalos no rebanho de um total de 3700 animais apresentaram infecção ocular durante o período compreendido entre dezembro de 2017 e novembro de 2018. Os esfregaços oculares foram colhidos dos olhos infectados dos búfalos afetados de ambos os sexos antes do tratamento. Os animais estavam em diferentes faixas etárias. Todas as amostras foram transferidas para o laboratório por meio de transferência e cultivadas em Ágar Sabouraud e Dextrose (SDA) com e sem 0,05 g/mL e 0,4 g/mL de cloranfenicol e cicloheximida, respectivamente. Posteriormente, os ágares foram incubados a 25ºC e 37ºC. A porcentagem total de infecção ocular foi de 6,75%, representando 49,2% de infecção micótica. As manifestações clínicas predominantes nos búfalos infectados foram inflamação ocular com congestão, lacrimejamento, opacidade da córnea e edema. Os animais acometidos também apresentaram redução de produtividade. Diferentes isolados de fungos foram identificados a partir das amostras, incluindo Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger, Penicillium spp., Alternaria spp., Fusarium spp., Candida spp., Cladosporium spp., Rhodotorula spp., Mucour spp. e Rizopus spp. Búfalos com menos de um ano de idade foram mais propensos a infecções micóticas do que com um ano ou mais. Além disso, os búfalos machos foram mais suscetíveis a infecção do que as fêmeas. Em conclusão, este estudo registrou o isolamento de vários tipos de fungos em olhos inflamados de búfalos. Além disso, a infecção ocular por fungos e os fatores de risco potenciais para ceratite fúngica em búfalos também foram observados. O estudo também aprovou o diagnóstico rápido de fungos por detecção microscópica direta e cultura. O autor recomenda outro estudo futuro, incluindo um grande número de rebanhos de búfalos no Iraque para determinar a epidemiologia desta condição no país.Buffaloes are one of the important farm animals in the south of Iraq and play an essential economical role mainly acting as dairy, meat, and draft animals. This study intended to diagnose buffalo mycotic eye infections in Thi-Qar province/Iraq. Some 250 buffaloes in the herd of 3,700 animals suffered from eye infections from December 2017 to November 2018. Eye swabs were collected from each infected eye of the affected buffaloes of both sexes before treatment. The animals were in different age groups. All samples were transferred to the laboratory in transfer media, and cultured on Sabouraud dextrose (SDA) agar with and without 0.05 g/mL and 0.4 g/mL chloramphenicol and cycloheximide, respectively. Later, the agars were incubated at 25o C and 37o C. The total percentage of eye infection was (6.75%), constituting (49.2%) mycotic infections. The predominant clinical manifestations that appeared on the infected buffaloes were eye inflammation represented by congestion, lacrimation, the opacity of cornea and edema, and reduced productivity of the infected animals. Different fungal isolates were identified from the samples including Aspergillus fumigates, Aspergillus flavus, Aspergillus niger, Penicillium spp., Alternaria spp., Fusarium spp., Candida spp., Cladosporium spp., Rhodotorula spp., Mucor spp. and Rhizopus spp. Calves buffaloes below one-year-old were more prone to mycotic infection than one-year-old or more. Additionally, male buffaloes were more susceptible to infection than females. In conclusion, this study isolated various types of fungus from the inflamed eyes of buffaloes. Fungal eye infection and the potential risk factors for fungal keratitis in buffaloes were also investigated. The study also approved the rapid diagnosis of fungi by direct microscopic detection and culture. The author recommends future studies including large numbers of the buffalo herd in Iraq to determine the epidemiology of this condition in the country.
Particulate organic carbon deconstructed: molecular and chemical composition of particulate organic carbon in the ocean
No full text© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Kharbush, J. J., Close, H. G., Van Mooy, B. A. S., Arnosti, C., Smittenberg, R. H., Le Moigne, F. A. C., Mollenhauer, G., Scholz-Boettcher, B., Obreht, I., Koch, B. P., Becker, K. W., Iversen, M. H., & Mohr, W. Particulate organic carbon deconstructed: molecular and chemical composition of particulate organic carbon in the ocean. Frontiers in Marine Science, 7, (2020): 518, doi:10.3389/fmars.2020.00518.The dynamics of the particulate organic carbon (POC) pool in the ocean are central to the marine carbon cycle. POC is the link between surface primary production, the deep ocean, and sediments. The rate at which POC is degraded in the dark ocean can impact atmospheric CO2 concentration. Therefore, a central focus of marine organic geochemistry studies is to improve our understanding of POC distribution, composition, and cycling. The last few decades have seen improvements in analytical techniques that have greatly expanded what we can measure, both in terms of organic compound structural diversity and isotopic composition, and complementary molecular omics studies. Here we provide a brief overview of the autochthonous, allochthonous, and anthropogenic components comprising POC in the ocean. In addition, we highlight key needs for future research that will enable us to more effectively connect diverse data sources and link the identity and structural diversity of POC to its sources and transformation processes.We thank the Hanse Institute for Advanced Studies (HWK) and the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) project number 422798570, as well as the Geochemical Society, for funding which made the workshop possible. CA was additionally supported by OCE-1736772. BV was additionally supported by NSF OCE-1756254
Design of an Information Security Model for Research Projects in the Environmental Area
No full textEste documento presenta la propuesta de diseño conceptual para un modelo de seguridad de la información aplicado a proyectos de investigación en el ámbito medioambiental. La iniciativa surge a partir de la necesidad de responder a las particularidades operativas y normativas de estos entornos, en los que se gestionan datos sensibles, distribuidos y sujetos a riesgos específicos. El modelo propuesto se estructura conforme al ciclo PHVA (Planificar, Hacer, Verificar, Actuar). Integra lineamientos de normas internacionales como ISO/IEC 27001:2022, ISO/IEC 27002:2022, ISO/IEC 27005:2022, MAGERIT v3 y NIST SP 800-53 Rev. 5. Esta base normativa permite establecer un enfoque sistemático para la identificación, análisis y tratamiento de riesgos, alineado con los objetivos de investigación y las condiciones técnicas del entorno. El diseño contempla políticas, prácticas y controles organizados por función (preventivos, detectivos, correctivos y disuasivos), clasificados según el nivel de riesgo de los activos y su nivel de madurez tecnológica. Sumado a esto, incorpora mecanismos de segmentación, trazabilidad y documentación que favorecen su aplicación en contextos institucionales o programas de investigación científica. El resultado es un modelo conceptual integral que, al alinear marcos normativos con las particularidades del sector, constituye una guía estratégica para fortalecer la protección de activos críticos y mejorar la resiliencia operativa en proyectos de investigación medioambiental.This document presents a conceptual design proposal for an information security model applied to environmental research projects. The initiative arises from the need to address the operational and regulatory particularities of these environments, where sensitive, distributed data are managed and subject to specific risks. The proposed model is structured according to the PDCA cycle (Plan, Do, Check, Act). It integrates guidelines from international standards such as ISO/IEC 27001:2022, ISO/IEC 27002:2022, ISO/IEC 27005:2022, MAGERIT v3, and NIST SP 800-53 Rev. 5. This normative foundation enables a systematic approach to the identification, analysis, and treatment of risks, aligned with research objectives and the technical conditions of the environment. The design includes policies, practices, and controls organized by function (preventive, detective, corrective, and deterrent), classified according to the risk level of the assets and their technological maturity. In addition, it incorporates segmentation, traceability, and documentation mechanisms that support its application in institutional contexts or scientific research programs. The result is a comprehensive conceptual model that, by aligning regulatory frameworks with sector-specific characteristics, serves as a strategic guide to strengthen the protection of critical assets and enhance operational resilience in environmental research projects
