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Wide-gap Cu(In,Ga)Se2 (CIGS) solar cells exhibit a superior match to the solar spectrum, resulting in a higher ideal efficiency (E ff). However, in reality, their device E ff is lower than that of narrow-gap CIGS solar cells. This study aims to identify the factors that limit the performance enhancement of wide-gap CIGS solar cells, focusing on the characteristics of the buffer layer. The influence of the thickness and doping concentration of the CdS layer on the built-in electric field and interfacial recombination of the heterojunction has been investigated through simulation. The simulation results indicate that when the doping concentration of the CdS layer is lower than or similar to that of the CGS layer, decreasing the thickness of the CdS layer (e.g., 10 nm) is beneficial for improving device performance. However, if it is higher than that of the CGS layer, increasing the thickness of the CdS layer (e.g., 50 nm) is conducive to improving device performance. The thickness of the CdS layer that maximizes the E ff of the wide-gap CGS device should be approximately 50 nm, and its doping concentration should be higher than that of the CGS layer. This optimization can simultaneously enhance the built-in electric field of the heterojunction and minimize its interfacial recombination, thereby improving the open-circuit voltage and E ff of wide-gap CGS devices.

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Purpose: This study aims to adapt and verify the psychometric properties of the Craving for Internet Gaming Scale (CIGS) in a Polish sample. Craving, although observed as significantly associated with Internet Gaming Disorder, is not currently included in its diagnostic criteria. This research addresses the need for scales to measure craving in this particular context. Methods: The research involved a sample of 575 participants. Psychometric analysis, including confirmatory factor analysis, was conducted to assess the CIGS' reliability and validity. Additional scales, such as the Game Transfer Phenomena Scale, Motives for Online Gaming Questionnaire, and the Depression Anxiety Stress Scales, were used for concurrent validity analysis. Results: The study results demonstrate the excellent psychometric properties of the Polish adaptation of the CIGS. It showed high reliability in terms of internal consistency and provided evidence for construct validity. Furthermore, it exhibited a positive correlation with various scales associated with problematic video game use and gaming addiction, while also showing a moderate negative correlation with self-control. Conclusions: Our findings suggest that the CIGS retains its psychometric properties in different cultures, making it a valuable instrument for comprehending craving within the context of Internet gaming disorder. Future research should focus on the adaptation of the CIGS to various cultural settings and the exploration of potential intergroup differences.

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End-of-life management of copper indium gallium selenide (CIGS) thin-film solar photovoltaics (PV) panels is crucial due to the necessity of recycling valuable elements such as indium ($400/kg) and gallium ($618/kg), ensuring both economic viability and environmental sustainability. In this study, we analyze the private and external costs of end-of-life management for CIGS PV designed for mass-scale recycling. Our findings reveal that the private and external costs of end-of-life management range from ∼$3.5 to $4.5 and ∼$3.0 to $4.0 per m2, respectively. The chemicals utilized in the recycling process, particularly NaOH and HCl, significantly contribute to climate change, photochemical oxidant formation, particulate matter formation, and freshwater eutrophication impact categories, accounting for ∼50 % to 90 % of the impacts. Furthermore, we found the net cost of recycling by subtracting the economic benefit obtained from recovered materials from the sum of private and external costs, revealing values ranging between $4.3 and $5.7 per m2 of CIGS PV module. These findings suggest that there is room to reduce the net cost further by recovering more materials from the CIGS PV modules components.

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The efficiency of copper indium gallium selenide (CIGS) solar cells that use transparent conductive oxide (TCO) as the top electrode decreases significantly as the device area increases owing to the poor electrical properties of TCO. Therefore, high-efficiency, large-area CIGS solar cells require the development of a novel top electrode with high transmittance and conductivity. In this study, a microgrid/TCO hybrid electrode is designed to minimize the optical and resistive losses that may occur in the top electrode of a CIGS solar cell. In addition, the buffer layer of the CIGS solar cells is changed from the conventional CdS buffer to a dry-processed wide-band gap ZnMgO (ZMO) buffer, resulting in increased device efficiency by minimizing parasitic absorption in the short-wavelength region. By optimizing the combination of ZMO buffer and the microgrid/TCO hybrid electrode, a device efficiency of up to 20.5% (with antireflection layers) is achieved over a small device area of 5 mm × 5 mm (total area). Moreover, CIGS solar cells with an increased device area of up to 20 mm × 70 mm (total area) exhibit an efficiency of up to 19.7% (with antireflection layers) when a microgrid/TCO hybrid electrode is applied. Thus, this study demonstrates the potential for high-efficiency, large-area CIGS solar cells with novel microgrid electrodes.

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The perovskite/Cu(InGa)Se2 (CIGS) tandem solar cells (TSCs) presents a compelling technological combination poised for the next generation of flexible and lightweight photovoltaic (PV) tandem devices, featuring a tunable bandgap, high power conversion efficiency (PCE), lightweight flexibility, and enhanced stability and durability. Over the years, the imperative to enhance the performance of wide bandgap (WBG) perovskite solar cells (PSCs) has grown significantly, particularly in the context of a flexible tandem device. In this study, an all-round passivation strategy known as Dual Passivation at Grains and Interfaces (DPGI) is introduced for WBG PSCs in perovskite/CIGS tandem structures. The implementation of DPGI is tailored to improve film crystallinity and passivate defects across the solar cell structure, leading to a substantial performance enhancement for WBG PSCs. Subsequently, both rigid and flexible tandem devices are assembled. Impressively, a fully flexible 4T perovskite/CIGS TSCs is successfully fabricated with a PCE of 26.57%, making it the highest value in this field and highlighting its potential applications in the next generation of flexible lightweight PV tandem devices.

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Second-generation thin-film Cu(In, Ga)Se2 (CIGS) solar cells are a well-established photovoltaic technology with a record power conversion efficiency of 23.6%. However, their reliance on critical raw materials, such as In and Ga, requires new approaches to reduce the amount of critical raw materials employed. The micro-concentrator concept involves the combination of thin-film photovoltaic technology with concentrator photovoltaic technology. This approach reduces the size of the solar cell to the micrometer range and uses optical concentration to collect sunlight from a larger area, focusing it onto micro solar cells. This work is devoted to the development of a process for manufacturing pre-structured substrates with regular arrays of holes with 200 and 250 µm diameters inside a SiOx insulating matrix. Subsequently, a Cu-In-Ga precursor is deposited by sputtering, followed by photoresist lift-off and the application of a Cu-In-Ga thermal annealing at 500 °C to improve precursor quality and assess pre-structured substrate stability under elevated temperatures. Finally, a two-stage selenization process leads to the formation of CIGS absorber micro-dots. This study presents in detail the fabrication process and explores the feasibility of a bottom-up approach using pre-structured substrates, addressing challenges encountered during fabrication and providing insights for future improvements in CIGS absorber materials.

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Background and Objectives: The widespread use of tobacco has evolved with the popularity of vapes, especially among young people, despite the lack of clarity in warnings about their risks. Studies indicate the need for more effective communication about the oral risks of vaping. In addition to systemic, respiratory, and cardiovascular effects, vaping is associated with an increased risk of gingivitis and periodontal disease as well as reduced antioxidant capacity of saliva. The objectives of this narrative review are to summarize the existing information in the literature on the effects of vaping at the oral level and to bring together knowledge about the mechanism of action of vaping in oral tissues. Materials and Methods: In the present study, articles were searched in PubMed, Elsevier Scopus, and Web of Science using the keywords "oral health", "vaping", and "vape". Studies published in the last 6 years that addressed the effects of oral vaping were selected, including comparisons among vape users, smokers, and non-smokers. Repeated articles, prior to 2017 and in languages other than English, were excluded. Two review authors (A.M.I and M.F.E.M) independently selected the papers based on titles and abstracts and conducted a full review of the remaining papers. In cases of disagreement, a third reviewer was used. Results: A total of 113 results were obtained, distributed as 16 from PubMed, 35 from Web of Science, and 62 from Elsevier Scopus. After removing duplicates, 67 articles were filtered by reviewing titles and abstracts, and finally, 22 articles were selected for comprehensive reading. Subsequently, eight of these articles were chosen for qualitative synthesis and are presented in standardized tables. The sample size of all included studies was composed of 31,647 participants, (14,477 male and 17,170 female) with a mean of 35.016 ± 7.57 years of age. Conclusions: This review indicates that the use of vapes is associated with an increased risk of periodontitis and caries. Although users experience more oral problems than non-smokers, these are less severe than those of traditional smokers. The widespread prevalence, especially among young people, highlights the urgency of awareness campaigns to warn of risks and understand potential harm.

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Small voids in the absorber layer of thin-film solar cells are generally suspected to impair photovoltaic performance. They have been studied on Cu(In,Ga)Se2 cells with conventional laboratory techniques, albeit limited to surface characterization and often affected by sample-preparation artifacts. Here, synchrotron imaging is performed on a fully operational as-deposited solar cell containing a few tens of voids. By measuring operando current and X-ray excited optical luminescence, the local electrical and optical performance in the proximity of the voids are estimated, and via ptychographic tomography, the depth in the absorber of the voids is quantified. Besides, the complex network of material-deficit structures between the absorber and the top electrode is highlighted. Despite certain local impairments, the massive presence of voids in the absorber suggests they only have a limited detrimental impact on performance.

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Conventional Copper Indium Gallium Di Selenide (CIGS)-based solar cells are more efficient than second-generation technology based on hydrogenated amorphous silicon (a-Si: H) or cadmium telluride (CdTe). So, herein the photovoltaic (PV) performance of CIGS-based solar cells has been investigated numerically using SCAPS-1D solar simulator with different buffer layer and less expensive tin sulfide (Sn2S3) back-surface field (BSF). At first, three buffer layer such as cadmium sulfide (CdS), zinc selenide (ZnSe) and indium-doped zinc sulfide ZnS:In have been simulated with CIGS absorber without BSF due to optimized and non-toxic buffer. Then the optimized structure of Al/FTO/ZnS:In/CIGS/Ni is modified to become Al/FTO/ZnS:In/CIGS/Sn2S3/Ni by adding a Sn2S3 BSF to enhanced efficiency. The detailed analysis have been investigated is the influence of physical properties of each absorber and buffer on photovoltaic parameters including layer thickness, carrier doping concentration, bulk defect density, interface defect density. This study emphasizes investigating the reasons for the actual devices' poor performance and illustrates how each device's might vary open-circuit voltage (VOC), short-circuit current density (JSC), fill factor (FF), power conversion efficiency (PCE), and quantum efficiency (QE). The optimized structure offers outstanding power conversion efficiency (PCE) of 21.83 % with only 0.80 µm thick CIGS absorber. The proposed CIGS-based solar cell performs better than the previously reported conventional designs while also reducing CIGS thickness and cost.

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An all-inorganic lead-free tandem PV cell consisting of two sub-cells CsSn0.5Ge0.5I3 (perovskite) based top cell/CIGS-based bottom cell has been designed, simulated, and optimized by varying the thickness of pertinent layers utilizing the SCAPS-1D simulator. In the top sub-cell, a wide bandgap lead-free inorganic CsSn0.5Ge0.5I3 perovskite is inserted as the primary absorber layer because of its distinctive characteristics with an ETL of ZnO, which is recognized for its high electron mobility & absorption coefficient, and an HTL of NiO to offer increased hole mobility with good chemical-durability. For the bottom sub-cell, we have selected p-type CIGS as the absorber with Spiro-OMeTAD as the apposite HTL to provide suitable offsets of valence and conduction band distribution and TiO2 as ETL to offer low-cost, low-ecotoxicity, excellent optical properties, and chemical-stability and thus offers improved efficiency of the overall tandem structure. In the beginning, the two sub-cells were simulated independently; the top sub-cell was simulated under the standard spectrum of AM1.5G, while the bottom sub-cell was optimized using a filtered spectrum. Thereafter, the current matching point of both cells was attained by optimizing the absorber layer thicknesses. Finally, our computational modeling and simulation results offer the optimized cell structure revealing an outstanding overall 38.39% power conversion efficiency (PCE), Fill Factor (FF) of 83.4%, open-circuit voltage (VOC) of 2.48 V, and short-circuit current density (Jsc) of 18.64 mA cm-2. The proposed tandem structure's performance matrices outperform those stated in the most recent literature. These outcomes of the proposed structure are expected to facilitate the development and production of a low-cost and highly effective inorganic perovskite Tandem PV cell in the future.

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In this paper, the performance of Cu-(In,Ga)-S2 (CIGS2) solar cells with adjusting composite [Cu]/([Ga] + [In]) (CGI)-ratio absorber was explored and compared through an improved three-stage co-evaporation technique. For co-evaporating CIGS2 absorber as a less toxic alternative to Cd-containing film, we analyzed the effect of the CGI-ratio stoichiometry and crystallinity, and explored its opto-electric sensing characteristic of individual solar cell. The results of this research signified the potential of high-performance CIGS2-absorption solar cells for photovoltaic (PV)-module industrial applications. For the optimal CIGS2-absorption film (CGI = 0.95), the Raman main-phase signal (A1) falls at 291 cm-1, which was excited by the 532 nm line of Ar+-laser. Using photo-luminescence (PL) spectroscopy, the corresponding main-peak bandgaps measured was 1.59 eV at the same CGI-ratio film. Meanwhile, the best conversion efficiency (η = 3.212%) and the average external quantum efficiency (EQE = 51.1% in the visible-wavelength region) of photo-electric properties were achieved for the developed CIGS2-solar cells (CGI = 0.95). The discoveries of this CIGS2-absorption PV research provided a new scientific understanding of solar cells. Moreover, this research undeniably contributes to a major advancement towards practical PV-module applications and can help more to build an eco-friendly community.

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Tandem solar cells (TSCs) have attracted prodigious attention for their high efficiency, which can surmount the Shockley-Queisser limit for single-junction solar cells. Flexible TSCs are lightweight and cost-effective, and are considered a promising approach for a wide range of applications. In this paper, a numerical model, based on TCAD simulation, is presented to assess the performance of a novel two-terminal (2T) all-polymer/CIGS TSC. To confirm the model, the obtained simulation results were compared with standalone fabricated all-polymer and CIGS single solar cells. Common properties of the polymer and CIGS complementary candidates are their non-toxicity and flexibility. The initial top all-polymer solar cell had a photoactive blend layer (PM7:PIDT), the optical bandgap of which was 1.76 eV, and the initial bottom cell had a photoactive CIGS layer, with a bandgap of 1.15 eV. The simulation was then carried out on the initially connected cells, revealing a power conversion efficiency (PCE) of 16.77%. Next, some optimization techniques were applied to enhance the tandem performance. Upon treating the band alignment, the PCE became 18.57%, while the optimization of polymer and CIGS thicknesses showed the best performance, reflected by a PCE of 22.73%. Moreover, it was found that the condition of current matching did not necessarily meet the maximum PCE condition, signifying the essential role of full optoelectronic simulations. All TCAD simulations were performed via an Atlas device simulator, where the light illumination was AM1.5G. The current study can offer design strategies and effective suggestions for flexible thin-film TSCs for potential applications in wearable electronics.

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Tandem solar cells usually use a wide band gap absorber for top cell. The band gap of CuIn(1-x)GaxSe2 can be changed from 1.04 eV to 1.68 eV with the ratio of Ga/(In+Ga) from 0 to 1. When the ratio of Ga/(In+Ga) is over 0.7, the band gap of CIGS absorber is over 1.48 eV. CIGS absorber with a high Ga content is a possible candidate one for the top cell. In this work, CuInGa precursors were prepared by magnetron sputtering with CuIn and CuGa targets, and CIGS absorbers were prepared by selenization annealing. The Ga/(In+Ga) is changed by changing the thickness of CuIn and CuGa layers. Additionally, CIGS solar cells were prepared using CdS buffer layer. The effects of Ga content on CIGS thin film and CIGS solar cell were studied. The band gap was measured by PL and EQE. The results show that using structure of CuIn/CuGa precursors can make the band gap of CIGS present a gradient band gap, which can obtain a high open circuit voltage and high short circuit current of the device. With the decrease in Ga content, the efficiency of the solar cell increases gradually. Additionally, the highest efficiency of the CIGS solar cells is 11.58% when the ratio of Ga/(In+Ga) is 0.72. The value of Voc is 702 mV. CIGS with high Ga content shows a great potential for the top cell of the tandem solar cell.

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Zinc sulfide (ZnS) thin films prepared using the chemical bath deposition (CBD) method have demonstrated great viability in various uses, encompassing photonics, field emission devices, field emitters, sensors, electroluminescence devices, optoelectronic devices, and are crucial as buffer layers of solar cells. These semiconducting thin films for industrial and research applications are popular among researchers. CBD appears attractive due to its simplicity, cost-effectiveness, low energy consumption, low-temperature compatibility, and superior uniformity for large-area deposition. However, numerous parameters influence the CBD mechanism and the quality of the thin films. This study offers a comprehensive review of the impact of various parameters that can affect different properties of ZnS films grown on CBD. This paper provides an extensive review of the film growth and structural and optical properties of ZnS thin films influenced by various parameters, which include complexing agents, the concentration ratio of the reactants, stirring speed, humidity, deposition temperature, deposition time, pH value, precursor types, and annealing temperature environments. Various studies screened the key influences on the CBD parameters concerning the quality of the resulting films. This work will motivate researchers to provide additional insight into the preparation of ZnS thin films using CBD to optimize this deposition method to its fullest potential.

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Objective: The use and effects of electronic (e)-cigarettes (e-cigs) are particularly relevant for otolaryngology providers as tobacco plays a major role in benign and malignant diseases of the upper aerodigestive tract. This review aims to (1) summarize the recent policies regarding e-cigs and important patterns of use and (2) serve as a comprehensive resource for clinical providers on the known biologic and clinical effects of e-cigs on the upper aerodigestive tract. Data Sources: PubMed/MEDLINE. Review Methods: We conducted a narrative review on (1) general information on e-cig use and informative findings in the lower respiratory system and a comprehensive review on (2) the effects of e-cigs on cell and animal models and the clinical implications of these products on human health as is relevant to otolaryngology. Conclusions: Although e-cigs are likely less harmful than conventional cigarettes, preliminary research on e-cigs suggest several deleterious effects including in the upper aerodigestive tract. Due to this, there has been increased interest in restricting e-cig usage, particularly among the adolescent population, and caution in recommending e-cigs to current smokers. Implications for Practice: Chronic e-cig use is likely to have clinical implications. It is critical for otolaryngology providers to be aware of the rapidly changing regulations and use patterns regarding e-cigs and how e-cigs influence human health, particularly with regards to the upper aerodigestive tract, to accurately council patients regarding potential risks and benefits of use.

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Indium has emerged as a strategic metal for high-tech and renewable industries, being catalogued as a critical material to foster a greener future. Nevertheless, its global sustainability is not well addressed. Here, using dynamic substance flow analysis, we study the indium industry evolution between 2010 and 2020 and estimate its future demand in the medium and long term toward 2050 to identify potential paths and mechanisms to decrease indium losses and to identify the key stages in its life cycle. As electronics and photovoltaic industries will play a crucial role in the indium demand, we assess their indium demand employing three cumulative photovoltaic capacity scenarios (8.5, 14, and 60 TW by 2050) with different dominant photovoltaic sub-technologies. Results show that liquid-crystal displays and photovoltaic panels will drive indium future demand, increasing its current demand by 2.2-4.2, 2.6-7.0, and 6.8-38.3 times for the 8.5, 14, and 60 TW scenarios, respectively, threatening with shortages that could occur as early as the next decade. Therefore, measures to reduce losses in primary production, innovations and improvements in electronics and solar panels, and indium recycling with an effective circular economy strategy could promote and secure the future sustainability of indium.

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The use of artificial intelligence to automate PV module fault detection, diagnosis, and classification processes has gained interest for PV solar plants maintenance planning and reduction in expensive inspection and shutdown periods. The present article reports on the development of an adaptive neuro-fuzzy inference system (ANFIS) for PV fault classification based on statistical and mathematical features extracted from outdoor infrared thermography (IRT) and I-V measurements of thin-film PV modules. The selection of the membership function is shown to be essential to obtain a high classifier performance. Principal components analysis (PCA) is used to reduce the dimensions to speed up the classification process. For each type of fault, effective features that are highly correlated to the PV module's operating power ratio are identified. Evaluation of the proposed methodology, based on datasets gathered from a typical PV plant, reveals that features extraction methods based on mathematical parameters and I-V measurements provide a 100% classification accuracy. On the other hand, features extraction based on statistical factors provides 83.33% accuracy. A novel technique is proposed for developing a correlation matrix between the PV operating power ratio and the effective features extracted online from infrared thermal images. This eliminates the need for offline I-V measurements to estimate the operating power ratio of PV modules.

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AIMS: This study aims to identify adolescent patterns of polytobacco use and measure transitions between patterns over time. DESIGN: Longitudinal analysis using data derived from waves 1-4 (2013-18) of the Population Assessment of Tobacco and Health (PATH) study. Transitions in tobacco use patterns were examined via latent transition analysis, and then, socio-demographic characteristics were used to predict transitions via logistic regression. SETTING: United States. PARTICIPANTS: Participants included 975 adolescents who used at least one tobacco product at any wave (W1 mean age = 13.29, standard deviation = 0.86; W4 54.2% male; 54.5% white, 25.9% Hispanic). MEASUREMENTS: Measurements included past 30-day use of cigarettes, electronic cigarettes (e-cigs), traditional cigars, cigarillos, filtered cigars, snus, smokeless tobacco (SLT) or hookah. FINDINGS: Six latent classes were identified. Cigarette users (43.5-58.8%) and SLT users (50.8-79.6%) tended to persist in their use over time. E-cig users began to probably transition to non-users (80.0%), but became more likely to persist in this use over time (31.1%). Non-users at a given wave were most likely to transition to e-cig users (8.5-43.7%) or cigarette users (6.7-28.6%). Cigarillo/poly-users and hookah/poly-users displayed more variable transition patterns. Adolescents were more likely to transition to non-use (versus become/remain e-cig users) if they were older (cigarette users, SLT users), younger (e-cig users), other race (SLT users), male (SLT users) or had less-educated parents (SLT users) compared with their counterparts. Hispanic (versus white) cigarette users were more likely to transition to non-users than to persist in this use. CONCLUSIONS: Among adolescents in the United States, patterns of tobacco use characterized by the use, mainly, of single, specific products appear to be stable, particularly by late adolescence. In contrast, patterns characterized by polytobacco use appear to be more variable and may represent experimentation without specialization.

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Objetivos: El propósito de esta investigación fue determinar el nivel de conocimiento, creencias, percepción y practicas asociadas al consumo de cigarrillos electrónicos en los estudiantes universitarios (UASD), recinto Santiago, República Dominicana. Cada estudiante firmó un consentimiento informado certificando que éste respondió cada pregunta realizada por el entrevistador de manera voluntaria. El método de recolección de los datos fue mediante entrevistas, las cuales fueron grabadas por los entrevistadores. La muestra fue de 53 entrevistas, 48 individuales y 5 grupos focales, la misma se tomó hasta alcanzar el punto de saturación de cada pregunta, es decir cuando todas las respuestas se tornaron repetitivas. Materiales y métodos: Se realizó un estudio cualitativo de tipo fenomenológico y de fuentes primarias en el período mayo-agosto del año 2019 en la universidad privada Pontificia Universidad Católica Madre y Maestra (PUCMM) y la universidad pública Universidad Autónoma de Santo Domingo. (UASD), campus Santiago, República Dominicana. El método de recolección de datos se realizó a través de entrevistas, las cuales fueron grabadas por los entrevistadores. Cada estudiante entrevistado firmó un consentimiento informado certificando que respondió voluntariamente a cada pregunta formulada por el entrevistador. La muestra estuvo compuesta por 53 entrevistas, 48 personas y cinco grupos focales. Las entrevistas se realizaron hasta llegar al punto de saturación de cada pregunta, que es cuando todas las respuestas se volvieron repetitivas. Resultados: El conocimiento que tiene los estudiantes universitarios sobre cigarrillo electrónico (CE), es pobre, desde su funcionamiento, partes, sustancias e incluso las posibles complicaciones que puede traer a la salud, tanto en la Pontificia Universidad Católica Madre y Maestra (PUCMM) como en la Universidad Autónoma de Santo Domingo (UASD), pero es más notable en la universidad pública. Por otro lado, muchos perciben el CE, como una alternativa del uso de tabaco, que posee diversidad de sabores, olor agradable, atractivo, práctico y capaz de ofrecer relajación. En cuanto a la actitud hacia el dispositivo, en PUCMM exhibe un mayor nivel de rechazo con respecto al uso. Es importante mencionar, que mayoría de los entrevistados son o alguna vez fueron usuarios de este, no obstante, no lo recomiendan en gran medida, ya que asumen que puede causar daño y ser adictivo, aunque en menor medida al cigarrillo convencional. La población más susceptible a su uso, son los jóvenes y el sexo masculino, aunque las féminas se han ido sumando de manera significativa. De igual modo, se logró apreciar las grandes influencias que mueven a los jóvenes a su consumo, incluyendo, las redes sociales, familia, amigos, en general el entorno en que se rodean. Conclusión: Concluimos que los estudiantes universitarios carecen de conocimiento con respecto al cigarrillo electrónico, tanto en el funcionamiento, sustancias y complicaciones para la salud. Muchos observan al cigarrillo electrónico como un dispositivo para fumar con un olor agradable, por lo cual puede ser muy atractivo para los usuarios. Se logró apreciar el importante papel que juegan las influencias sociales para el uso del dispositivo, promovido por las redes sociales y relaciones cercanas. Otro problema en la sociedad actual es el uso de CE en menores de edad. Según los resultados existe una gran necesidad de intervención y educación, principalmente en los jóvenes.

Objective: The purpose of this research was to determine the level of knowledge, beliefs, perception, and practices associated with consuming electronic cigarettes among university students. Materials and methods: A qualitative study of phenome-nological type and from primary sources was carried out in the period of May-August of the year 2019 at the private university Pontificia Universidad Católica Madre y Mae-stra (PUCMM) and the public university Universidad Autónoma de Santo Domingo (UASD), Santiago campus, Dominican Republic. The data collection method was done through interviews, which the interviewers recorded. Each student interviewed signed an informed consent cer-tifying that they answered voluntarily each question asked by the interviewer. The sample consisted of 53 interviews, 48 individuals, and five focus groups. Interviews were done until reaching the saturation point of each question, which is when all the answers became repetitive. Results: University students' knowledge regarding elec-tronic cigarettes (EC) is poor. Knowledge regarding its mechanism, parts, substances, and possible complications to one's health, is scarce both in PUCMM and the UASD, but this is more notable at the public university. Addition-ally, many perceive EC as an alternative to tobacco use, the former, as per our study population, having a variety of fla-vors, a pleasant smell, being attractive, practical, and capa-ble of offering relaxation. Regarding the attitude towards the device, PUCMM exhibits a higher level of rejection regarding its use. It is essential to mention that most inter-viewees were once users of EC. However, they do not rec-ommend it to a great extent since they assume that it can cause harm and be addictive, although to a lesser extent than conventional cigarettes. The population most suscep-tible to its use are young people, including minors and the male gender, although females have been significantly increasing its use. Similarly, it was possible to appreciate the influences that greatly evoke the younger population's consumption, including social networks, family, friends, and the surrounding environment. Conclusion: We concluded that university students have insufficient knowledge regarding electronic cigarettes, both in their mechanism, substances, and health compli-cations. Most see electronic cigarettes as smoking devices with a pleasant smell, which can be very attractive to users. It was possible to observe the critical role played by social influences on the use of the device, promoted by social networks and close relationships. Another problem in cur-rent society is the use of CE in minors. According to the results, there is a great need for intervention and educa-tion, mainly among the younger generation.

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Chalcopyrite-based materials for photovoltaic devices tend to exhibit complex structural imperfections originating from their polycrystalline nature; nevertheless, properly controlled devices are surprisingly irrelevant to them in terms of resulting device performances. The present work uses atom probe tomography to characterize co-evaporated high-quality Cu(In,Ga)Se2 (CIGS) films on flexible polyimide substrates either with or without doping with Na or doping with Na followed by K via a post-deposition treatment. The intent is to elucidate the unique characteristics of the grain boundaries (GBs) in CIGS, in particular the correlations/anti-correlations between matrix elements and the alkali dopants. Various compositional fluctuations are identified at GBs irrespective of the presence of alkali elements. However, [Cu-poor and Se/In,Ga-rich] GBs are significantly more common than [Cu-rich and Se/In,Ga-poor] ones. In addition, the anti-correlations between Cu and the other matrix elements are found to show not only regular trends among themselves but also the association with the degree of alkali segregation at GBs. The Na and K concentrations exhibited a correlation at the GBs but not in the intragrain regions. Density functional theory calculations are used to explain the compositional fluctuations and alkali segregation at the GBs. Our experimental and theoretical findings not only reveal the benign or beneficial characteristics of the GBs of CIGS but also provide a fundamental understanding of the GB chemistry in CIGS-based materials.