Search results for: Rocio Pina

Authors: Mina Rabipour, Elena Pallaske, Floyd Hassenrück, Rocio Rebollido-Rios

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Protein tyrosine kinases, including Lyn kinase of the Src family kinases (SFK), regulate cell proliferation, survival, and differentiation. Lyn kinase has been implicated in various cancers, positioning it as a promising therapeutic target. However, the conserved ATP-binding pocket across SFKs makes developing selective inhibitors challenging. This study aims to address this limitation by exploring the potential for allosteric modulation of Lyn kinase, focusing on how its structural dynamics and specific oncogenic mutations impact its conformation and function. To achieve this, we combined homology modeling, molecular dynamics simulations, and data science techniques to conduct microsecond-length simulations. Our approach allowed a detailed investigation into the interplay between Lyn’s catalytic and regulatory domains, identifying key conformational states involved in allosteric regulation. Additionally, we evaluated the structural effects of Dasatinib, a competitive inhibitor, and ATP binding on Lyn active conformation. Notably, our simulations show that cancer-related mutations, specifically I364L/N and E290D/K, shift Lyn toward an inactive conformation, contrasting with the active state of the wild-type protein. This may suggest how these mutations contribute to aberrant signaling in cancer cells. We conducted a dynamical network analysis to assess residue-residue interactions and the impact of mutations on the Lyn intramolecular network. This revealed significant disruptions due to mutations, especially in regions distant from the ATP-binding site. These disruptions suggest potential allosteric sites as therapeutic targets, offering an alternative strategy for Lyn inhibition with higher specificity and fewer off-target effects compared to ATP-competitive inhibitors. Our findings provide insights into Lyn kinase regulation and highlight allosteric sites as avenues for selective drug development. Targeting these sites may modulate Lyn activity in cancer cells, reducing toxicity and improving outcomes. Furthermore, our computational strategy offers a scalable approach for analyzing other SFK members or kinases with similar properties, facilitating the discovery of selective allosteric modulators and contributing to precise cancer therapies.

Keywords: lyn tyrosine kinase, mutation analysis, conformational changes, dynamic network analysis, allosteric modulation, targeted inhibition

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Authors: Rocío González-Sánchez, Sara Alonso-Muñoz

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Food waste implies an inefficient management of the final stages in the food supply chain. Referring to Sustainable Development Goals (SDGs) by United Nations, the SDG 12.3 proposes to halve per capita food waste at the retail and consumer level and to reduce food losses. In the linear system, food waste is disposed and, to a lesser extent, recovery or reused after consumption. With the negative effect on stocks, the current food consumption system is based on ‘produce, take and dispose’ which put huge pressure on raw materials and energy resources. Therefore, greater focus on the circular management of food waste will mitigate the environmental, economic, and social impact, following a Triple Bottom Line (TBL) approach and consequently the SDGs fulfilment. A mixed methodology is used. A total sample of 311 publications from Web of Science database were retrieved. Firstly, it is performed a bibliometric analysis by SciMat and VOSviewer software to visualise scientific maps about co-occurrence analysis of keywords and co-citation analysis of journals. This allows for the understanding of the knowledge structure about this field, and to detect research issues. Secondly, a systematic literature review is conducted regarding the most influential articles in years 2020 and 2021, coinciding with the most representative period under study. Thirdly, to support the development of this field it is proposed an agenda according to the research gaps identified about circular economy and food waste management. Results reveal that the main topics are related to waste valorisation, the application of waste-to-energy circular model and the anaerobic digestion process towards fossil fuels replacement. It is underlined that the use of food as a source of clean energy is receiving greater attention in the literature. There is a lack of studies about stakeholders’ awareness and training. In addition, available data would facilitate the implementation of circular principles for food waste recovery, management, and valorisation. The research agenda suggests that circularity networks with suppliers and customers need to be deepened. Technological tools for the implementation of sustainable business models, and greater emphasis on social aspects through educational campaigns are also required. This paper contributes on the application of circularity to food waste management by abandoning inefficient linear models. Shedding light about trending topics in the field guiding to scholars for future research opportunities.

Keywords: bibliometric analysis, circular economy, food waste management, future research lines

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Authors: Ortiz M. Rocío, Rocha G. Karina, Domenech A. Gloria

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There are several tools to assess the nutritional status of the population. A main instrument commonly used to build those tools is the food composition tables (FCT). Despite the importance of FCT, there are many error sources and variability factors that can be presented on building those tables and can lead to an under or over estimation of ingest of nutrients of a population. This work identified different food composition tables used as an instrument to estimate the nutrient ingest in Ecuador.The collection of data for choosing FCT was made through key informants –self completed questionnaires-, supplemented with institutional web research. A questionnaire with general variables (origin, year of edition, etc) and methodological variables (method of elaboration, information of the table, etc) was passed to the identified FCT. Those variables were defined based on an extensive literature review. A descriptive analysis of content was performed. Ten printed tables and three databases were reported which were all indistinctly treated as food composition tables. We managed to get information from 69% of the references. Several informants referred to printed documents that were not accessible. In addition, searching the internet was not successful. Of the 9 final tables, n=8 are from Latin America, and, n= 5 of these were constructed by indirect method (collection of already published data) having as a main source of information a database from the United States department of agriculture USDA. One FCT was constructed by using direct method (bromatological analysis) and has its origin in Ecuador. The 100% of the tables made a clear distinction of the food and its method of cooking, 88% of FCT expressed values of nutrients per 100g of edible portion, 77% gave precise additional information about the use of the table, and 55% presented all the macro and micro nutrients on a detailed way. The more complete FCT were: INCAP (Central America), Composition of foods (Mexico). The more referred table was: Ecuadorian food composition table of 1965 (70%). The indirect method was used for most tables within this study. However, this method has the disadvantage that it generates less reliable food composition tables because foods show variations in composition. Therefore, a database cannot accurately predict the composition of any isolated sample of a food product.In conclusion, analyzing the pros and cons, and, despite being a FCT elaborated by using an indirect method, it is considered appropriate to work with the FCT of INCAP Central America, given the proximity to our country and a food items list that is very similar to ours. Also, it is imperative to have as a reference the table of composition for Ecuadorian food, which, although is not updated, was constructed using the direct method with Ecuadorian foods. Hence, both tables will be used to elaborate a questionnaire with the purpose of assessing the food consumption of the Ecuadorian population. In case of having disparate values, we will proceed by taking just the INCAP values because this is an updated table.

Keywords: Ecuadorian food composition tables, FCT elaborated by direct method, ingest of nutrients of Ecuadorians, Latin America food composition tables

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Authors: Mylena McCoggle, Shyra Wilson, Andrea Rivera, Rocio Alba-Flores

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This work introduces the use of EMGs (electromyography) from muscle sensors to develop an Artificial Neural Network (ANN) for pattern recognition to control a small unmanned aerial vehicle. The objective of this endeavor exhibits interfacing drone applications beyond manual control directly. MyoWare Muscle sensor contains three EMG electrodes (dual and single type) used to collect signals from the posterior (extensor) and anterior (flexor) forearm and the bicep. Collection of raw voltages from each sensor were connected to an Arduino Uno and a data processing algorithm was developed with the purpose of interpreting the voltage signals given when performing flexing, resting, and motion of the arm. Each sensor collected eight values over a two-second period for the duration of one minute, per assessment. During each two-second interval, the movements were alternating between a resting reference class and an active motion class, resulting in controlling the motion of the drone with left and right movements. This paper further investigated adding up to three sensors to differentiate between hand gestures to control the principal motions of the drone (left, right, up, and land). The hand gestures chosen to execute these movements were: a resting position, a thumbs up, a hand swipe right motion, and a flexing position. The MATLAB software was utilized to collect, process, and analyze the signals from the sensors. The protocol (machine learning tool) was used to classify the hand gestures. To generate the input vector to the ANN, the mean, root means squared, and standard deviation was processed for every two-second interval of the hand gestures. The neuromuscular information was then trained using an artificial neural network with one hidden layer of 10 neurons to categorize the four targets, one for each hand gesture. Once the machine learning training was completed, the resulting network interpreted the processed inputs and returned the probabilities of each class. Based on the resultant probability of the application process, once an output was greater or equal to 80% of matching a specific target class, the drone would perform the motion expected. Afterward, each movement was sent from the computer to the drone through a Wi-Fi network connection. These procedures have been successfully tested and integrated into trial flights, where the drone has responded successfully in real-time to predefined command inputs with the machine learning algorithm through the MyoWare sensor interface. The full paper will describe in detail the database of the hand gestures, the details of the ANN architecture, and confusion matrices results.

Keywords: artificial neural network, biosensors, electromyography, machine learning, MyoWare muscle sensors, Arduino

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Authors: Ana L. M. Pavan, Guilherme Giacomini, Allan F. F. Alves, Marcela De Oliveira, Fernando A. B. Neto, Maria E. D. Rosa, Andre P. Trindade, Diana R. De Pina

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Mammography is a worldwide image modality used to diagnose breast cancer, even in asymptomatic women. Due to its large availability, mammograms can be used to measure breast density and to predict cancer development. Women with increased mammographic density have a four- to sixfold increase in their risk of developing breast cancer. Therefore, studies have been made to accurately quantify mammographic breast density. In clinical routine, radiologists perform image evaluations through BIRADS (Breast Imaging Reporting and Data System) assessment. However, this method has inter and intraindividual variability. An automatic objective method to measure breast density could relieve radiologist’s workload by providing a first aid opinion. However, pectoral muscle is a high density tissue, with similar characteristics of fibroglandular tissues. It is consequently hard to automatically quantify mammographic breast density. Therefore, a pre-processing is needed to segment the pectoral muscle which may erroneously be quantified as fibroglandular tissue. The aim of this work was to develop an automatic algorithm to segment and extract pectoral muscle in digital mammograms. The database consisted of thirty medio-lateral oblique incidence digital mammography from São Paulo Medical School. This study was developed with ethical approval from the authors’ institutions and national review panels under protocol number 3720-2010. An algorithm was developed, in Matlab® platform, for the pre-processing of images. The algorithm uses image processing tools to automatically segment and extract the pectoral muscle of mammograms. Firstly, it was applied thresholding technique to remove non-biological information from image. Then, the Hough transform is applied, to find the limit of the pectoral muscle, followed by active contour method. Seed of active contour is applied in the limit of pectoral muscle found by Hough transform. An experienced radiologist also manually performed the pectoral muscle segmentation. Both methods, manual and automatic, were compared using the Jaccard index and Bland-Altman statistics. The comparison between manual and the developed automatic method presented a Jaccard similarity coefficient greater than 90% for all analyzed images, showing the efficiency and accuracy of segmentation of the proposed method. The Bland-Altman statistics compared both methods in relation to area (mm²) of segmented pectoral muscle. The statistic showed data within the 95% confidence interval, enhancing the accuracy of segmentation compared to the manual method. Thus, the method proved to be accurate and robust, segmenting rapidly and freely from intra and inter-observer variability. It is concluded that the proposed method may be used reliably to segment pectoral muscle in digital mammography in clinical routine. The segmentation of the pectoral muscle is very important for further quantifications of fibroglandular tissue volume present in the breast.

Keywords: active contour, fibroglandular tissue, hough transform, pectoral muscle

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Authors: Elisa Santana-Monagas, Juan L. Núñez, Jaime León, Samuel Falcón, Celia Fernández, Rocío P. Solís

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Teaching practices have been widely studied in relation to students' outcomes, positioning themselves as one of their strongest catalysts and influencing students' emotional experiences. In the higher education context, teachers become even more crucial as many students ground their decisions on which courses to enroll in based on opinions and ratings of teachers from other students. Unfortunately, sometimes universities do not provide the personal, social, and academic stimulation students demand to be actively engaged. To evaluate their teachers, universities often rely on students' evaluations of teaching (SET) collected via Likert scale surveys. Despite its usefulness, such a method has been questioned in terms of validity and reliability. Alternatively, researchers can rely on qualitative answers to open-ended questions. However, the unstructured nature of the answers and a large amount of information obtained requires an overwhelming amount of work. The present work presents an alternative approach to analyse such data: sentiment analysis. To the best of our knowledge, no research before has included results from SA into an explanatory model to test how students' sentiments affect their emotional engagement in class. The sample of the present study included a total of 225 university students (Mean age = 26.16, SD = 7.4, 78.7 % women) from the Educational Sciences faculty of a public university in Spain. Data collection took place during the academic year 2021-2022. Students accessed an online questionnaire using a QR code. They were asked to answer the following open-ended question: "If you had to explain to a peer who doesn't know your teacher how he or she communicates in class, what would you tell them?". Sentiment analysis was performed using Microsoft's pre-trained model. The reliability of the measure was estimated between the tool and one of the researchers who coded all answers independently. The Cohen's kappa and the average pairwise percent agreement were estimated with ReCal2. Cohen's kappa was .68, and the agreement reached was 90.8%, both considered satisfactory. To test the hypothesis relations among SA and students' emotional engagement, a structural equation model (SEM) was estimated. Results demonstrated a good fit of the data: RMSEA = .04, SRMR = .03, TLI = .99, CFI = .99. Specifically, the results showed that student’s sentiment regarding their teachers’ teaching positively predicted their emotional engagement (β == .16 [.02, -.30]). In other words, when students' opinion toward their instructors' teaching practices is positive, it is more likely for students to engage emotionally in the subject. Altogether, the results show a promising future for sentiment analysis techniques in the field of education. They suggest the usefulness of this tool when evaluating relations among teaching practices and student outcomes.

Keywords: sentiment analysis, students' evaluation of teaching, structural-equation modelling, emotional engagement

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Authors: Rocio Murad, Juan Carlos Rivillas, Nury Alejandra Rodriguez, Daniela Roldán

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In Colombia, around 5 million women have suffered forced displacement and all forms of gender-based violence, mostly adolescents and young women, single mothers, or widows with children affected by the war. After the signing of the peace agreements, the department of Antioquia has been one of the most affected by the armed conflict, from a territorial and gender perspective in the period. The objective of the research was to analyze the situation of sexual and reproductive rights in the department of Antioquia from a territorial and gender perspective in the period after the signing of the Peace Agreement. A mixed methodology was developed. The quantitative component conducted a cross-sectional descriptive study of barriers to access to contraceptive methods, safe abortion and gender-based violence based on microdata from the 2015 National Demographic and Health Survey. In the qualitative component, a case study was developed in Dabeiba, a municipality of Antioquia prioritized in order to deepen the experiences before, during and after the armed conflict in sexual and reproductive rights; using three research techniques: Focused observation, Semi-structured interviews, and Documentary review. The results showed that there is a gradient of greater vulnerability to greater effects of the conflict and that the subregion of Urabá Antioqueño, to which Dabeiba belongs, has the highest levels of vulnerability in relation to departmental data. In this subregion, the percentage of women with an unmet need for contraceptive methods (9%), women with unintended pregnancies (31%), of women between 15 and 19 years of age who are already mothers or are pregnant with their first child (32%) and the percentage of women victims of physical violence (42%) and sexual violence (13%) by their partners are significantly higher. Women, particularly rural and indigenous women, were doubly affected due to the existence of violence that is specifically directed at them or that has a greater impact on their life projects. There was evidence of insufficient, fragmented and disjointed social and institutional action in relation to women's rights and the existence of androcentric and patriarchal social imaginaries through which women and the feminine are undervalued. These results provide evidence of violations of sexual and reproductive rights in contexts of armed conflict and make it possible to identify mechanisms to guarantee the re-establishment of the rights of the victims, particularly women and girls. Among the mechanisms evidenced are: working for the elimination of gender stereotypes; supporting the formation and strengthening of women's social organizations; working for the concerted definition and articulated implementation of actions necessary to respond to sexual and reproductive health needs; and working for the recognition of reproductive violence as specific and different from sexual violence in the context of armed conflict. Also, it was evidenced that it is necessary to implement prevention, attention and reparation actions.

Keywords: sexual and reproductive rights, Colombia, armed conflict, violence against women

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Authors: Elisa Santana-Monagas, Juan L. Núñez, Jaime León, Samuel Falcón, Celia Fernández, Rocío P. Solís

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Students’ emotional experiences have been a widely discussed theme among researchers, proving a central role on students’ outcomes. Yet, up to now, far too little attention has been paid to teaching practices that negatively relate with students’ negative emotions in the higher education. The present work aims to examine the relationship between teachers’ teaching practices (i.e., students’ evaluations of teaching and autonomy support), the students’ feelings of boredom and agentic engagement and motivation in the higher education context. To do so, the present study incorporates one of the most popular tools in natural processing language to address students’ evaluations of teaching: sentiment analysis. Whereas most research has focused on the creation of SA models and assessing students’ satisfaction regarding teachers and courses to the author’s best knowledge, no research before has included results from SA into an explanatory model. A total of 225 university students (Mean age = 26.16, SD = 7.4, 78.7 % women) participated in the study. Students were enrolled in degree and masters’ studies at the faculty of Education of a public university of Spain. Data was collected using an online questionnaire students could access through a QR code they completed during a teaching period where the assessed teacher was not present. To assess students’ sentiments towards their teachers’ teaching, we asked them the following open-ended question: “If you had to explain a peer who doesn't know your teacher how he or she communicates in class, what would you tell them?”. Sentiment analysis was performed with Microsoft's pre-trained model. For this study, we relied on the probability of the students answer belonging to the negative category. To assess the reliability of the measure, inter-rater agreement between this NLP tool and one of the researchers, who independently coded all answers, was examined. The average pairwise percent agreement and the Cohen’s kappa were calculated with ReCal2. The agreement reached was of 90.8% and Cohen’s kappa .68, both considered satisfactory. To test the hypothesis relations a structural equation model (SEM) was estimated. Results showed that the model fit indices displayed a good fit to the data; χ² (134) = 351.129, p < .001, RMSEA = .07, SRMR = .09, TLI = .91, CFI = .92. Specifically, results show that boredom was negatively predicted by autonomy support practices (β = -.47[-.61, -.33]), whereas for the negative sentiment extracted from SET, this relation was positive (β = .23[.16, .30]). In other words, when students’ opinion towards their instructors’ teaching practices was negative, it was more likely for them to feel bored. Regarding the relations among boredom and student outcomes, results showed a negative predictive value of boredom on students’ motivation to study (β = -.46[-.63, -.29]) and agentic engagement (β = -.24[-.33, -.15]). Altogether, results show a promising future for sentiment analysis techniques in the field of education as they proved the usefulness of this tool when evaluating relations among teaching practices and student outcomes.

Keywords: sentiment analysis, boredom, motivation, agentic engagement

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Authors: Cátia Gonçalves, Teresa Nunes, Inês Pina, Ana Vicente, C. Alves, Felix Charvet, Daniel Neves, A. Matos

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The production of charcoal relies on rudimentary technologies using traditional brick kilns. Charcoal is produced under pyrolysis conditions: breaking down the chemical structure of biomass under high temperature in the absence of air. The amount of the pyrolysis products (charcoal, pyroligneous extract, and flue gas) depends on various parameters, including temperature, time, pressure, kiln design, and wood characteristics like the moisture content. This activity is recognized for its inefficiency and high pollution levels, but it is poorly characterized. This activity is widely distributed and is a vital economic activity in certain regions of Portugal, playing a relevant role in the management of woody residues. The location of the units establishes the biomass used for charcoal production. The Portalegre district, in the Alto Alentejo region (Portugal), is a good example, essentially with rural characteristics, with a predominant farming, agricultural, and forestry profile, and with a significant charcoal production activity. In this district, a recent inventory identifies almost 50 charcoal production units, equivalent to more than 450 kilns, of which 80% appear to be in operation. A field campaign was designed with the objective of determining the composition of the emissions released during a charcoal production cycle. A total of 30 samples of particulate matter and 20 gas samples in Tedlar bags were collected. Particulate and gas samplings were performed in parallel, 2 in the morning and 2 in the afternoon, alternating the inlet heads (PM₁₀ and PM₂.₅), in the particulate sampler. The gas and particulate samples were collected in the plume as close as the emission chimney point. The biomass (dry basis) used in the carbonization process was a mixture of cork oak (77 wt.%), holm oak (7 wt.%), stumps (11 wt.%), and charred wood (5 wt.%) from previous carbonization processes. A cylindrical batch kiln (80 m³) with 4.5 m diameter and 5 m of height was used in this study. The composition of the gases was determined by gas chromatography, while the particulate samples (PM₁₀, PM₂.₅) were subjected to different analytical techniques (thermo-optical transmission technique, ion chromatography, HPAE-PAD, and GC-MS after solvent extraction) after prior gravimetric determination, to study their organic and inorganic constituents. The charcoal production cycle presents widely varying operating conditions, which will be reflected in the composition of gases and particles produced and emitted throughout the process. The concentration of PM₁₀ and PM₂.₅ in the plume was calculated, ranging between 0.003 and 0.293 g m⁻³, and 0.004 and 0.292 g m⁻³, respectively. Total carbon, inorganic ions, and sugars account, in average, for PM10 and PM₂.₅, 65 % and 56 %, 2.8 % and 2.3 %, 1.27 %, and 1.21 %, respectively. The organic fraction studied until now includes more than 30 aliphatic compounds and 20 PAHs. The emission factors of particulate matter to produce charcoal in the traditional kiln were 33 g/kg (wooddb) and 27 g/kg (wooddb) for PM₁₀ and PM₂.₅, respectively. With the data obtained in this study, it is possible to fill the lack of information about the environmental impact of the traditional charcoal production in Portugal. Acknowledgment: Authors thanks to FCT – Portuguese Science Foundation, I.P. and to Ministry of Science, Technology and Higher Education of Portugal for financial support within the scope of the project CHARCLEAN (PCIF/GVB/0179/2017) and CESAM (UIDP/50017/2020 + UIDB/50017/2020).

Keywords: brick kilns, charcoal, emission factors, PAHs, total carbon

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Authors: Rocio Murad, Marcela Sanchez, Mariana Calderon Jaramillo, Danny Rivera, Angela Cifuentes, Daniela Roldán, Juan Carlos Rivillas

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Women and girls have specific health needs, but during health pandemics such as COVID19 they are less likely to have access to quality essential health information, commodities and services, or insurance coverage for routine and catastrophic health expenses, especially in rural and marginalized communities. This is compounded by multiple or intersecting inequalities, such as ethnicity, socioeconomic status, disability, age, geographic location, and sexual orientation, among others. Despite concerted collective action, there is a lack of information on the situation of women, adolescents and youth, including gender inequalities exacerbated by the pandemic. Much more needs to be done to amplify the lived realities of women and adolescents in global and national advocacy and policy responses. The COVID 19 pandemic reflects the need for systematic advocacy policies based on the lived experiences of women and adolescents, underpinned by human rights. This research is part of the initiative of Profamilia Association (Solidarity Study), and its objective is twofold: i) to analyze the behavioral changes and immediate expectations of Colombians during the stage of relaxation of the confinement measures decreed by the national government; and ii) to identify the needs, experiences and resilient practices of adolescents and young women during the COVID-19 crisis in Colombia. Descriptive analysis of data collected by Profamilia through the Solidaridad study, an exploratory cross-sectional descriptive study that used subnational level data from a nonprobabilistic sample survey conducted to 1735 adults, between September 01 and 11, 2020. Interviews were conducted with key stakeholders about their experiences during COVID19, under three key axes: i) main challenges for adolescents and young women; ii) examples of what has worked well in responding to the challenge; and iii) how/what services are/should be provided during COVID-19 (and beyond) to address the challenge. Interviewees were selected based on prior mapping of social groups of interest. In total, 23 adolescents and young women participated in the interviews. The results show that people adopted behavioral changes such as wearing masks, avoiding people with symptoms, and reducing mobility, but there was also a doubling of concerns for many reasons, from effects on mental health, sexual health, and unattended reproductive health to the burden of care and working at home. The favorable perception that people had at the beginning of the quarantine about the response and actions of the national and local government to control Covid-19 decreased over the course of the quarantine. The challenges and needs of adolescents and young women were highlighted during the most restrictive measures to contain the COVID-19 pandemic, which resulted in disruptions to daily activities, education and work, as well as restrictions to mobility and social interaction. Concerns raised by participants included: impact on mental health and wellbeing due to disruption of daily life; limitations in access to formal and informal education; food insecurity; migration; loss of livelihoods; lack of access to health information and services; limitations to sexual and reproductive health and rights; insecurity problems; and problems in communication and treatment among household members.

Keywords: COVID-19, changes in behavior, adolescents, women

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