bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of K-W-L Instructional Strategy on Academic Performance of Pupils in Primary Mathematics and English in Owerri North Lga of Imo State, Nigeria
Authors: Ijeoma Nbisike Marvel , Ogechi Nbisike Gyna-Sam , Onyinyechi Dara Angela , I. Eluemuno Azukaego , Ngozi Nwaneri Patience
Published: March 2024

The purpose of this study was to find out if learners taught algebraic expression/elementary statistics in Mathematics and parts of speech in English Language using K-W-L instructional strategy will have better academic performance than those taught with the conventional Teacher method at 0.05 alpha levels. The researchers used quasi-experimental design which adopted the pretest, post-test Experimental group method. The area of study was Owerri North LGA Imo State, Nigeria. The population of the study was all Primary 5 learners in Owerri North Public schools. Purposive sampling technique was used to select three primary schools and simple random sampling technique was used to select classes in each of the schools. The sample of the study was 120 primary learners. The data collection instruments for the study were treatment 1 (K-W-L instructional strategies), treatment 2, (TCM [Teacher conventional method), Treatment 3 (combined TCM & K-W-L), multiple-choice questions for each subject chosen from past FSLCE and Common entrance questions. Two research questions and one null hypothesis guided the study. Mean, standard deviation and ANCOVA were the statistical tools used to analyze the data. The findings of the study revealed that the group taught with combined TCM & K-W-L achieved higher academically than the group taught with only TCM or K-W-L. The study also discovered that K-W-L instructional strategy is gender friendly. It was recommended that primary school teachers should be encouraged to use K-W-L instructional strategy to facilitate learners’ performance in algebraic expression, elementary statistics and parts of speech. Furthermore Basic Education Stake holders should organize regular workshops and seminars to train and retrain teachers on the use of 21st century teaching strategies.
SALA DE LEITURA UM ESPAÇO DE MOTIVAÇÃO E INCENTIVO A LEITURA
Authors: De Albuquerque Machado Lais Maria Medeiros
Published: March 2024

This research aims to broaden the discourse on the reading room as a space for motivation and encouragement for reading. In the reading room, the methodology applied in children's education focuses on promoting reading as a fundamental practice in student development. Its objectives are to specify, discuss, analyze, and compare what various authors say on the subject. This article seeks to highlight the importance of practical reading with the aim of learning, better understanding oneself, and one's trajectory. Being a space for human formation that promotes interdisciplinarity, the reading room should be considered a construction space where various literary information is gathered with different types of reading, aiming to stimulate the student's desire to become a great researcher or reader, enabling their integration into social contexts through reading and writing. It serves as a socializing, critical environment, ensuring readers the possibility of good expression, a desired capacity in contemporary society. It aims to develop the habit and appreciation for reading, expanding the teacher's knowledge regarding themselves and their experiences in society, fostering critical, personal, and cultural thoughts.
Exploring the binding affinity of rutin, catechin, and epicatechin to ALK and caspase-3: implications for colorectal cancer treatment
Authors: Adhyaksa I Nyoman Mahesa Praba , Pramesti Ni Luh Putu Cintya , Susanti Ni Made Pitri , Laksmiani Ni Putu Linda
Published: March 2024

This study explores the interaction of rutin, catechins, and epicatechins with anaplastic lymphoma kinase (ALK) and caspase-3, focusing on their potential role in modulating the apoptotic mechanisms in colorectal cancer cells. The experimental approach included the preparation of ALK (PDB ID: 5USQ) and caspase-3 (PDB ID: 2XZT), validation of the docking process, optimization of the test compounds, and docking analyses. The molecular docking methodology was validated with an RMSD value of ≤ 3 Å. The docking outcomes revealed that rutin, catechins, and epicatechin exhibited lower binding affinity to ALK, with binding energies of -8.58 kcal/mol, -8.41 kcal/mol, and -7.82 kcal/mol, respectively, compared to ALK's native ligand (-10.27 kcal/mol). Conversely, these compounds demonstrated higher affinity to caspase-3 than its native ligand (-2.54 kcal/mol), with binding energies of -6.03 kcal/mol for rutin, -5.28 kcal/mol for catechins, and -4.95 kcal/mol for epicatechin. These findings suggest that rutin, catechins, and epicatechins hold promise as colorectal anticancer agents by potentially modulating the activity of ALK and caspase-3 through inhibition and activation mechanisms, respectively.
ANALYSIS OF REALIZED ACTIVITIES OF THE TOURIST COMMUNITY OF SARAJEVO CANTON
AND THEIR PRESENTATION THROUGH THE WEBSITE AND SOCIAL NETWORKS FOR THE
PROMOTION OF SPORTS TOURISM AND TOURISM
Authors: Hodžić Amer , Huremović Tarik , Džibrić Dževad
Published: March 2024

Abstract
Tourist boards, through their social activities, can make a tourist destination, tourist attractions and tourist products
attractive, unique, and special. Through relevant scientific knowledge, using the tools and techniques of destination
management as well as modern forms of communication, tourist boards can make the entire area of a tourist destination
very interesting and desirable for tourist visits throughout the year by promoting the specificity, authenticity and originality
of the tourist offer and tourist products.
Keywords: tourist board; tourism promotion through sports and sports recreation competitions; tourism promotion through
social networks, tourism
Priapismo isquémico en la enfermedad falciforme como causa de disfunción sexual. Serie de casos y revisión de la literatura
Authors: Iglesias-Jiménez Oscar Giovanny , Sierra Merlano Rita Magola , Toro Osorio Keyner
Published: March 2024

La enfermedad falciforme (EF) comprende un grupo de trastornos hereditarios con expresión clínica heterogénea y múltiples complicaciones de índole vascular y hemolítica. El priapismo representa una emergencia urológica que amerita intervención quirúrgica temprana para disminuir la disfunción eréctil. Objetivos: informar cinco casos de EF atendidos por priapismo en la ESE Hospital Universitario de Cartagena (ESEHUC) resaltando las características sociodemográficas, clínicas y de laboratorio que se asociaron a disfunción eréctil. Métodos: serie de casos hospitalaria. Resultados: se registraron cinco casos de priapismo con mediana calculada para edad de 33 años, IMC: 23 kg/m2, tres casos pertenecieron al subtipo homocigoto, uno doble heterocigoto y un rasgo de la EF. La media de ingreso hospitalario se consideró tardía siendo mayor a 48 horas de evolución del priapismo y en todos se optó por el manejo quirúrgico urológico. Tres casos presentaron disfunción sexual, uno clasificado severo. Conclusiones: los casos con formas subclínicas y genotipos de bajo riesgo pueden enfrentarse a priapismo mayor, con riesgo de padecer complicaciones con impacto sobre la vida sexual. Se insiste en educar a los pacientes sobre la consulta temprana y estilos de vida quedisminuyan el riesgo de priapismo.
Avances en la clasificación molecular de los tumores cerebrales
Authors: Cardona Andrés Felipe , Jacobo Javier , Aristizábal Jorge
Published: March 2024

En 1918 Percival Bailey completó su entrenamiento médico, tras lo cual perseguía ansiosamente el esquivo conocimiento sobre la fisiología cerebral.  Con la esperanza de continuar su formación, Percival Bailey envió cartas a dos miembros destacados de la comunidad médica, un psiquiatra y, el otro, un neurocirujano. Harvey Cushing le respondió primero, por lo que Bailey se reunió con él en el Hospital Brigham de Boston, lugar donde había acumulado un extenso depósito de muestras de tumores cerebrales. Tiempo después, valorando las piezas, ambos médicos descubrieron que algunas lesiones agresivas crecían rápidamente, mientras que otras seguían un curso benigno. Durante la evaluación macroscópica, Bailey agrupó 400 especímenes según el tiempo de supervivencia, correlacionando su apariencia con los resultados clínicos después del procedimiento neuroquirúrgico. Después de dos mil cirugías, Cushing y Bailey demostraron que la estructura celular de un tumor podía guiar el tratamiento inicial y el pronóstico.
PENGEMBANGAN LABORATORIUM VIRTUAL BERBASIS TIKTOK PADA MATA KULIAH PRAKTIKUM KIMIA DASAR 1 UNTUK MENINGKATKAN KETERAMPILAN BERPIKIR KRITIS DAN PROSES SAINS
Authors: Utami Aisyiah Restutiningsih Putri , Mustapa Mustapa , Manaari Chaleb Paul , Agustina Tika Putri , Rukmana Musma , Ermita Ermita
Published: March 2024

Tujuan penelitian yang sudah dilakukan adalah pembuatan dan pengembangan media pembelajaran berupa laboratorium virtual menggunakan aplikasi Tiktok. Virtual laboratorium yang sudah dibuat adalah laboratorium untuk mata kuliah praktikum kimia dasar 1. Media yang dikembangkan dibuat untuk meningkatkan keterampilan berpikir kritis. Selain itu juga ditujukan untuk meningkatkan keterampilan proses sains mahasiswa. Pada penelitiian ini menggunakan pendekatan penelitian model ADDIE. Adapun validasi dilakukan dengan validasi ahli materi dan ahli media. Masing-masing validator berjumlah 2 (dua) orang ahli. Nilai rata-rata uji validasi ahli materi adalah 93,6%, dan 88,1% untuk validasi media. Hal ini berarti bahwa media pembelajaran berupa virtual laboratorium tiktok sangat layak untuk digunakan sebagai sumber pembelajaran. Proses selanjutnya adalah melakukan uji kepraktisan dan keefektifan pada mahasiswa program studi pendidikan kimia semester 1 kelas A dan B. Pengumpulan data dilakukan dengan instrumen observasi, wawancara, dan angket. Selanjutnya, analisis data dilakukan dengan metode statistik deskriptif. Berdasarkan penelitian pengembangan yang sudah dilakukan, dismpulkan bahwa laboratorium virtual berbasis Tiktok sangat layak, praktis, dan efektif untuk digunakan pada pembelajaran kimia dasar 1 dengan persentase keefektifan sebesar 89,7%. Hal ini menunjukkan bahwa produk yang dibuat dapat meningkatkan keterampilan proses sains dan berpikir kritis mahasiswa.
The Audit Expectation Gap: Literature Review
Authors: EL BADLAOUI Anass , NAJI Saida , CHEGRI Badreeddine
Published: March 2024

The purpose of this paper is to review recent empirical literature on the components and reducing factors of the Audit Expectation Gap distinguishing research conducted in developed countries relative to developing countries. We adopt a systematic literature review to review papers published between 2010 and 2020. To do so, we conducted a methodological process that combines an electronic search and a manual analysis to extract and analyze data. The results of our literature review show that fewer studies have been conducted in developed countries than in developing countries, because the AEG is no longer a contemporary theme in developed countries. Researchers from developed countries have revealed the existence of AEG, firstly, in the areas of auditor responsibilities, and especially in fraud detection and prevention. In order to mitigate AEG, audit education is seen as the primary factor in reducing AEG. Extending our study to developing countries, a clearer picture of AEG is found predominantly in auditors’ responsibilities in prevention and detection of fraud and other illegal acts and unreasonable expectations of public and auditor’s features. In order to reduce AEG, three factors are widely cited in the literature in developing countries: Audit education; Enhancement of auditor performance and Increasing the information content of audit reports.
A INTELIGÊNCIA ARTIFICIAL NO CONTEXTO DA CULTURA DIGITAL E OS DESAFIOS NA EDUCAÇÃO
Authors: Reis Douglas do Nascimento , Almeida Danielle Portela de , Nascimento Isidro José Bezerra Maciel Fortaleza do , Bédard Maria do Carmo Bezerra Maciel , Gomes Renato Duarte , Carloni Alessandro Ramos , Anjos Elivaldo Francisco dos , Santos Carlos Alberto Feitosa dos
Published: March 2024

A atualidade tem experimentado uma série de transformações sociais desencadeada pelos avanços tecnológicos que facilitaram a execução de inúmeras atividades cotidianas, tanto nos afazeres domésticos das pessoas em geral quanto na rotina comercial e industrial das organizações. Essas inovações tecnológicas transformaram o mundo, substituíram atividades, potencializaram a criação de novas necessidades e instituíram uma nova era conhecida como “cultura digital” ou cibercultura. É nesse cenário de rápidas mudanças que vários setores tentaram se adaptar para obter os melhores resultados com o uso das ferramentas tecnológicas disponíveis para o avanço de suas atividades. A educação também foi um desses setores. Com a chegada da última geração de ferramentas de inteligência artificial (IA), educadores e instituições de ensino estão em busca de adaptar suas metodologias e abrir novos caminhos em prol do ensino e da aprendizagem. Diante disso, o presente artigo tem como objetivo analisar como as recentes inovações e ferramentas de IA, como os chatbots, podem contribuir para a elaboração de novas metodologias de ensino e aperfeiçoar as já existentes. Para isso, serão revisados estudos científicos publicados nos últimos anos que abordam o tema, analisando as estratégias utilizadas pelos docentes que já fazem uso dessas ferramentas, seus benefícios e limitações no ensino e aprendizagem.
O PAPEL DA EDUCAÇÃO EM SAÚDE NA PRÁTICA DE ENFERMAGEM DURANTE O PRÉ-NATAL: PROMOVENDO A SAÚDE MATERNA E PERINATAL
Authors: Areia Ávyla dos Santos Ferreira , Martins Heloyse Freitas , Fernandes Natália Almeida , Reis Rafael Sandro Lima , Rocha Júnior Ismael Aluísio Figueiredo da
Published: March 2024

Introdução: Aborda a importância da saúde materna e perinatal, destacando o papel da enfermagem na promoção da educação em saúde durante o pré-natal. Justificativa: Destaca a relevância do estudo diante dos desafios na saúde materna e perinatal, ressaltando a necessidade de compreender o impacto da educação em saúde na prática de enfermagem pré-natal. Objetivo: Explorar o papel da educação em saúde na enfermagem durante o pré-natal no Brasil, investigando práticas atuais e seu impacto nos resultados maternos e neonatais. Métodos: Realização de uma revisão integrativa da literatura, com critérios de inclusão e exclusão definidos para seleção de estudos relevantes, seguida de análise qualitativa e quantitativa dos dados. Resultados: Apresentação dos achados da revisão, destacando práticas de educação em saúde pré-natal, impacto nos resultados maternos e neonatais, além de lacunas na literatura. Discussões: Análise dos resultados à luz da literatura existente, explorando contribuições, limitações e implicações práticas, bem como sugerindo direções para pesquisas futuras. Conclusão: Apresentação das principais conclusões do estudo e recomendações para aprimorar os cuidados pré-natais no Brasil, visando melhorar os resultados de saúde materna e neonatal.
CLINICAL FEATURES OF ACUTE CYTOMEGALOVIRUS INFECTION ACCOMPANIED BY THROMBOTIC COMPLICATIONS IN IMMUNOCOMPETENT PATIENTS
Authors: I. Hutsaliuk , M. Dotsenko
Published: March 2024

Objective of the study. To identify and analyse clinical and laboratory features in immunocompetent patients with thrombotic complications in acute cytomegalovirus infection. Development of the algorithm of prognosis and early diagnosis of thrombotic complications in order to reduce the risk of severe course of the disease and lethal outcome. Materials and Methods. The study included 100 immunocompetent adult patients undergoing inpatient observation and treatment with laboratory-proven acute cytomegalovirus infection. All patients had a detailed clinical and epidemiological history for the possible presence of modifiable and/or non-modifiable prothrombotic risk factors; a multifaceted laboratory and instrumental examination was performed. Results. Out of one hundred patients with acute cytomegalovirus infection selected in the study, thrombotic diseases were observed in 7% of cases (in 7 patients). The mean age of the patients was 41 (38; 42) years. Patients were hospitalised on average on 12 (10; 14) days from the onset of the disease. The main complaints on admission were: prolonged fever up to 38°C and marked general weakness. The patients had elevated ALT and AST in 88% and 80% of cases, respectively. The presence of reactive lymphocytes was registered in 57% of cases. Enlargement of liver and spleen was observed in 67% and 70% of cases, respectively. Compared to patients with uncomplicated course of acute cytomegalovirus infection, statistically significant laboratory differences were observed in SRB (p<0.001) and D-dimers (p<0.05) in patients who had thrombotic complications. All patients who had genetic material (DNA) to CMV in the blood had positive tests for rr65 antigenemia. The polymorphism of factor V gene G1691A (FVLeiden) was detected in only one patient, who was a carrier of heterozygous GA allele. Conclusion. Acute cytomegalovirus infection in immunocompetent patients includes a symptom complex consisting of a typical clinical picture (prolonged febrile intoxication, hepatosplenomegaly, elevated hepatic transaminases, CRP and D-dimer levels) and obligatory laboratory detection of the virus (positive PCR and/or Ag pp65 tests for CMV). Cytomegalovirus is an independent and reliable prothrombotic risk factor, with thrombotic complications occurring in 7% of cases. Patients with risk factors for thrombotic complications with verified acute cytomegalovirus infection are recommended to be prescribed anticoagulant therapy at prophylactic doses. Also, patients with a proven case of thrombotic process on the background of acute cytomegalovirus infection are recommended a course of etiotropic antiviral therapy.
The algorithm of microphysical parameter profiles of aerosol and small cloud droplets based on the dual wavelength Lidar data
Authors: Di Huige , Wang Xinhong , Chen Ning , Guo Jing , Xin Wenhui , Li Shichun , Guo Yan , Yan Qing , Wang Yufeng , Hua Dengxin
Published: March 2024

Abstract. This study proposed an inversion method of atmosphere aerosol or cloud microphysical parameters based on dual wavelength lidar data. The matching characteristics between aerosol/cloud particle size distribution and Gamma distribution were studied using aircraft observation data. The feasibility of particle effective radius retrieval from lidar ratio and backscatter ratio was simulated and studied. A method for inverting the effective radius and number concentration of atmospheric aerosols or small cloud droplets using backscatter ratio was proposed, and the error sources and applicability of the algorithm were analyzed. This algorithm was suitable for the inversion of uniformly mixed and single property aerosol layers or small cloud droplets. Compared with the previous study, this algorithm could quickly obtain the microphysical parameters of atmosphere particles and has good robustness. For aerosol particles, the inversion range that this algorithm can achieve was 0.3–1.7 μm. For cloud droplets, it was 1.0–10 μm. An atmosphere observation experiment was conducted using the multi-wavelength lidar developed by Xi'an University of Technology, and a thin cloud formation process was captured. The microphysical parameters of aerosol and cloud during this process were retrieved. The results clearly demonstrate the growth of effective radius and number concentration.
A quasi-one-dimensional ice mélange flow model based on continuum descriptions of granular materials
Authors: Amundson Jason M. , Robel Alexander A. , Burton Justin C. , Nissanka Kavinda
Published: March 2024

Abstract. Field and remote sensing studies suggest that ice mélange influences glacier-fjord systems by exerting stresses on glacier termini and releasing large amounts of freshwater into fjords. The broader impacts of ice mélange over long time scales are unknown, in part due to a lack of suitable ice mélange flow models. Previous efforts have included modifying existing viscous ice shelf models, despite the fact that ice mélange is fundamentally a granular material, and running computationally expensive discrete element simulations. Here, we draw on laboratory studies of granular materials, which exhibit viscous flow when stresses greatly exceed the yield point, plug flow when the stresses approach the yield point, and stress transfer via force chains. By implementing the nonlocal granular fluidity rheology into a depth- and width-integrated stress balance equation, we produce a numerical model of ice mélange flow that is consistent with our understanding of well-packed granular materials and that is suitable for long time-scale simulations. For parallel-sided fjords, the model exhibits two possible steady state solutions. When there is no calving of new icebergs or melting of previously calved icebergs, the ice mélange is pushed down fjord by the advancing glacier terminus, the velocity is constant along the length of the fjord, and the thickness profile is exponential. When calving and melting are included, the ice mélange evolves to another steady state in which its location is fixed relative to the fjord walls, the thickness profile is relatively steep, and the flow is extensional. For the latter case, the model predicts that the steady-state ice mélange buttressing force depends on the surface and basal melt rates through an inverse power law relationship, decays roughly exponentially with both fjord width and gradient in fjord width, and increases with the iceberg calving flux. The increase in buttressing force with the calving flux, which depends on glacier thickness, appears to occur more rapidly than the force required to prevent the capsize of full-glacier-thickness icebergs, suggesting that glaciers with high calving fluxes may be more strongly influenced by ice mélange than those with small fluxes.
Tropical upper tropospheric trends in ozone and carbon monoxide (2005–2020): observational and model results
Authors: Froidevaux Lucien , Kinnison Douglas E. , Gaubert Benjamin , Schwartz Michael J. , Livesey Nathaniel J. , Read William G. , Bardeen Charles G. , Ziemke Jerry R. , Fuller Ryan A.
Published: March 2024

Abstract. We analyze tropical ozone (O3) and carbon monoxide (CO) distributions in the upper troposphere (UT) and their temporal changes for 2005–2020 using Aura Microwave Limb Sounder (MLS) observations and chemistry climate models. The models are the Whole Atmosphere Community Climate Model (WACCM6) and two variants of the Community Atmosphere Model with Chemistry (CAM-chem), each variant using different anthropogenic emissions. Upper tropospheric trends and variability diagnostics are obtained from multiple linear regression analyses. We compare the model and MLS annual climatologies, focusing on 147 and 215 hPa pressure levels; climatological values generally fall within 10–20 % of each other, with both positive and negative differences for O3, and with models generally underestimating observed CO. In the northern hemisphere tropics, we find significantly poorer model fits to the observed phasing of CO seasonal changes at 215 hPa than at 147 hPa. This discrepancy is much smaller for the comparison of modeled and Measurements of Pollution in the Troposphere (MOPITT) V9J CO columns. We also find that the sensitivity of UT CO to El Niño / Southern Oscillation (ENSO) is positive at all tropical longitudes, in contrast to the dipolar longitudinal structure that exists for UT O3 ENSO sensitivity. MLS O3 has a zonal mean trend at 20° S–20° N of +0.39 ± 0.28 % yr-1; CAM-chem and WACCM have similar trends, though the WACCM trend is somewhat smaller. Our analyses for specific latitude/longitude bins yield positive trends up to 1.4 % yr-1 over Indonesia and East of that region, as well as over tropical Africa and the tropical Atlantic. We find broad similarities between the mapped MLS-derived UT O3 trends and corresponding mapped trends of tropospheric column ozone. Positive tropical UT mapped O3 trends are generally captured by the models, although in a more muted way. There is room for improvements in modeled tropical UT CO trends. Indeed, the MLS zonal mean CO trend is -0.25 ± 0.30 % yr-1, whereas the corresponding modeled CO trends are near zero (0.0 ± 0.14 % yr-1) when the anthropogenic emissions used in CAM-chem and WACCM are taken from Community Emissions Data System (CEDS) version 2. The non-CEDS version of CAM-chem yields CO UT trends of 0.22 ± 0.19 % yr-1, in contrast to the negative MLS CO trends throughout the tropics. The negative MLS tropical UT CO trends for 2005–2020 agree with (but tend to be smaller in magnitude than) previously published total column CO trends. Decreasing CO emissions from anthropogenic and biomass burning sources have previously been suggested as the main causes of tropospheric CO decreases, although significant regional emission trend variations exist.
From marine to brine and back – a new box model approach to investigate the external influences on the Messinian salinity crisis  
Authors: Ebner Ronja , Meijer Paul , Aloisi Giovanni
Published: March 2024

The Messinian Salinity Crisis is an event that not only led to the youngest known salt giant, but also impacted the global ocean salinity due to the mass of ions trapped in the Mediterranean Sea. Understanding its full implications requires comprehensive understanding of the events, and due to limitations in data acquisition, modeling is essential to bridge knowledge gaps.Our latest box model aims to include those processes and aspects that have been indicated to be the most influential by previous model studies. It is forced by (1) a reconstructed freshwater budget with the option to include a salinity feedback, (2) the depth of the Sstrait of Gibraltar and (3) changes in the sea level of the Atlantic. The circulation in the Mediterranean includes the exchange between the eastern and the western basin across the sill  of Sicily on the horizontal level, as well as vertical exchange between two layers. The shapes of the boxes are determined by the hypsometry of the basin, which allows for realistic drawdown and refilling scenarios. The latter offers the option to test the influence of the Paratethys.To assess the validity of scenarios, the model output is compared to the volume of the known deposits as well as the cycles recorded in gypsum outcrops. An additional tracer in the model is the Sr isotope signal. Our findings highlight the importance of horizontal gradients in explaining gypsum deposits in the western basin, unlike the more uniform distribution of gypsum and halite the model produces in the eastern basin. While the onset of gypsum deposition may not necessarily differ between the basins, our results support the theory that halite precipitation began earlier in the east than in the west. This type of model will not answer all questions, but it might guide us to the new ones.
Long-term soil redox dynamics of intact and degraded permafrost in Interior Alaska
Authors: Liebmann Patrick , Vogel Cordula , Barta Jiri , Urich Tim , Kholodov Alexander , Varsadiya Milan , Waqas Muhammad , Wang Haitao , Donnerhack Oliver , Shibistova Olga , Wessel-Bothe Stefan , Mansfeldt Tim , Guggenberger Georg
Published: March 2024

Permafrost degradation, freezing and thawing processes, and poor drainage due to underlain frozen ground have far-reaching consequences on soil hydrology and biology and, thus, on the redox dynamic in soils of the Arctic. Assessing the redox status of these soils is essential for understanding soil organic matter decomposition processes and can be done by temporal measurements in the field, analyses of redox-sensitive elements, or identification of microbial species or enzymes in redox process chains. While such approaches provide snippets of the complex redox dynamic, publications reporting long-term in-situ redox potential (EH) measurements in arctic permafrost soils are scarce. Limited accessibility to study sites and technical limitations in measuring the redox potential in a frozen environment may be two reasons for this research gap.But how does the redox potential develop in permafrost soils at different depths in the active layer during the summer? What happens during freezing and thawing? Finally, do thawing/degrading permafrost soils show different patterns compared to intact permafrost?We approached these research questions by installation of a unique soil monitoring setup at 3 sites near Fairbanks, Alaska, in August 2021. An intact permafrost soil (active layer depth about 50 cm) was equipped with 3 redox electrodes (for EH) and 3 hydra probes (for water content and soil temperature) in the topsoil and subsoil, respectively, and connected to a logger unit allowing continuous measurement of these parameters in both depths every 15 minutes. In addition, two sites with advanced permafrost degradation (permafrost level below 100 cm) were equipped in the same way. One degraded site featured large water contents, representing a wet thaw scenario, while the other site was well-drained, representing a dry thaw scenario, thus representing different endmembers of the ongoing climate-change induced permafrost thaw.Here, we present the first 2 years of soil monitoring in a discontinuous permafrost area in Interior Alaska from 09/2021 to 09/2023. Overall, pH values of all soils varied between 4.5-6.3. The dry thaw scenario showed oxic conditions (i.e., EH >600 mV) in top- and subsoil, while water contents were low. The wet thaw scenario exhibited high topsoil redox potentials (i.e., EH >500 mV), while subsoil redox potential was lower (i.e., EH 400 mV in the summer period (August to October), suggesting less oxygen consumption in this recently thawed permafrost subsoil.
Surface wave mantle anisotropy tomography of the Azores-Madeira-Canaries region using UPFLOW data: initial results
Authors: Harris Katrina , Witek Michael , Ferreira Ana M. G. , Chang Sung-Joon , Miranda Miguel
Published: March 2024

Upward mantle flow is key to understand global mantle geodynamics yet its imaging remains challenging due to potential associated low velocity contrasts and small lateral dimensions. In this study we use the UPFLOW ocean bottom seismometer (OBS) dataset to build images of radial anisotropy to constrain the patterns of mantle upwellings in the Azores-Madeira-Canary Islands region. We use the partitioned waveform inversion (PWI) method whereby non-linear waveform fitting of surface waves filtered between T~ 16 s and T~ 300 s is performed using a successive series of time-frequency windows in two stages. Firstly, the surface wave fundamental mode is extracted via phase match filtering and is used to obtain path average perturbations in shear radial anisotropy and isotropic shear wave velocity from a smoothed combination of the 1-D mantle model ak135 and the crustal model CRUST1.0. These perturbations establish a new initial model, which is subsequently used to estimate the path averaged radial anisotropy model that leads to the best fit between the observed trace and the synthetic waveform obtained by summing all overtones (up to n = 20). An iterative, regularized least squares inversion is used to invert for 3-D radially anisotropic mantle structure. Uncertainties are automatically quantified and used to interpret resolved seismic structures. Preliminary results are compared to previous tomographic models of the Atlantic region.
Role played by Organic Nitrates in the Production of Secondary Organic Aerosol in a megacity
Authors: Aruffo Eleonora , Wang Junfeng , Jacob Daniel J. , Ye Jianhuai , Ge Xinlei , Di Carlo Piero
Published: March 2024

Secondary Organic Aerosol (SOA) production and chemical composition play a crucial role in the urban air pollution. Here, we used observations from two summer campaigns in Beijing in 2017 and 2023 to show that nighttime production of NOz (NOy - NOx) is particularly enhanced in specific conditions and that can play a significant role for SOA the next day. The observations showed nocturnal peaks of NOz of about 40 ppb, correlated with very high NO and NO2. We employed the Framework for 0-D Atmospheric Modeling (F0AM) model, based on the Master Chemical Mechanism (MCM), running simulations to investigate the organic nitrates (ONs) speciation, and founding that during the night the alkyl nitrates is the most abundant ONs, produced by oxidation of volatile organic compounds (VOCs) by the nitrate radical (NO3). Finally, we used the Framework for 0-D Atmospheric Modeling- Washington Aerosol Module (F0AM-WAM) model, which couple the gas phase chemistry with the SIMPOL representation for the particle phase, to correlate the nocturnal ONs peaks, that we suggested to be mainly in gas phase, to the diurnal particle growth events registered in Beijing.
Direct analysis of marine dissolved organic matter using LC-FT-ICR MS
Authors: Lechtenfeld Oliver , Kaesler Jan , Jennings Elaine , Koch Boris
Published: March 2024

Marine dissolved organic matter (DOM) is an important component of the global carbon cycle, yet its intricate composition and the sea salt matrix pose major challenges for chemical analysis. The current view on marine DOM as assessed with ultrahigh resolution mass spectrometry (UHR-MS) is largely based on SPE-extracts known for its consistent underestimation of e.g. the mean nominal oxidation state of carbon (NOSC) and molecular weight as compared to bulk measurements. We introduce a direct injection, reversed-phase liquid chromatography Fourier-transform ion cyclotron resonance (FT-ICR) MS approach to analyze marine DOM without the need for solid-phase extraction. Effective separation of salt and DOM is achieved with a large chromatographic column and an extended isocratic aqueous step. Post-column dilution of the sample flow with buffer-free solvents and implementing a counter gradient reduced salt buildup in the ion source and resulted in excellent repeatability. With this method over 5,500 unique molecular formulas were detected from just 5.5 nmol of carbon in 100 µL filtered Arctic Ocean seawater. We observed highly linear detector response for variable sample carbon concentrations and a high robustness against the salt matrix. We could demonstrate the bias of SPE in marine DOM on a molecular level leading to a predominant detection of less polar DOM, while neglecting a large fraction of polar, heteroatom-rich DOM. In addition, a substantial fraction of terrestrial-derived DOM was previously overlooked in solid-phase extracted marine DOM. Overall, the direct analysis of seawater offers fast and simple sample preparation and avoids fractionation introduced by extraction. The method facilitates studies in environments, where only minimal sample volume is available e.g. in marine sediment pore water, ice cores, or permafrost soil solution. The small volume requirement also supports higher spatial (e.g. in soils) or temporal sample resolution (e.g. in culture experiments). Chromatographic separation adds further chemical information to molecular formulas, enhancing our understanding of marine biogeochemistry, chemodiversity, and ecological processes.
The chemical composition of the discharged fluid from IDDP-2, Reykjanes, Iceland
Authors: Galeczka Iwona , Óskarsson Finnbogi , Gebrehiwot Mesfin Kiflom
Published: March 2024

The IDDP-2 well at Reykjanes was drilled by Iceland Drilling Ltd. for HS Orka Ltd. in 2016 and 2017. The well was drilled as part of the Iceland Deep Drilling Project (IDDP), which aim has been to drill deep wells down to 4–5 km depth into geothermal systems in Iceland, involved casing and deepening the production well RN-15 from 2507 m to 4659 m.  Deepening of the well commenced on August 11th, 2016, and it was completed on January 25th, 2017. The most recent well test of RN-15/IDDP-2 was on 5th of May 2022. The well has a casing damage just below 2300 m depth, which hinders any logging below that depth. The main feed zones are probably at the depth of the casing damage (where the main feed zone of RN-15 was located) and at about 3400 m, but there may also be a minor feed zone near the bottom of the well. When the well is opened for discharge, fluid from these feed zones enters the wellbore, flows up the well and eventually reaches a boiling point. The fluid is then two-phase with a gradually increasing steam fraction up to the wellhead. The estimated enthalpy of the discharged fluid is from about 1107 kJ/kg to 1120 kJ/kg and the steam fraction is about 30%. The production from the well was 19.2 kg/s and 22.2 kg/s at wellhead pressure 13.5 bar-g and 7.8 bar-g, respectively. The estimated productivity index is 1.4 (kg/s)/bar, which indicates low-permeability feed zones.The geothermometry of the collected fluid sample suggests a slightly higher reservoir temperature of 294°C compared to 290°C in 2016. Note that this difference is within analytical uncertainty for SiO2 analysis. The highest gas content measured during this study was 1.83 wt% and is higher than most of the RN wells. The deep fluid feeding the well is more diluted comparing to the fluid from RN-15 pre-2016. Most of the major non-volatiles are in a low range of the concentrations calculated for the Reykjanes reservoir. The RN-15/IDDP-2 aquifer is, however, enriched in volatiles such as CO2, H2S, N2, and H2 compared to their content during monitoring or RN-15 in 2004-2016. In general, the temperature and the composition suggest that fluid entering the well is not only sourced from 2300 m aquifer but also from deeper feed zones. The IDDP-2 was funded by HS Orka, LV, OR and OS, in Iceland, together with Equinor (former Statoil). The IDDP-2 also received funding from the EU H2020 (DEEPEGS grant no.690771) for all parts of the operation, and ICDP and US NSF (grant No.05076725) for spot coring and part of the related research
Modelling the Hydro-fracture driven collapse of the Larsen B ice shelf
Authors: ONeill James , Gasson Ed
Published: March 2024

Ice shelves play a key role in buttressing upstream ice - modulating the flow of grounded ice into the ocean and in turn affecting ice sheet contribution to sea level. Iceberg calving, which has approximately equalled thinning in terms of mass loss from Antarctic ice shelves since 2007, is an important ablation process for balancing accumulation. However, rapid ice shelf disintegration, driven by surface melting, can dramatically impact grounded ice dynamics on relatively short time scales. In 2002, the Larsen B ice shelf lost ~60% of its area, following extensive surface melt ponding, observed over months.  This event has been associated with a ‘hydro-fracture’ mode of ice shelf collapse, where surface melt ponds enhance surface crevasse penetration, causing the ice shelf to disintegrate. Following the collapse of Larsen B, retreat of its largest tributary glacier increased by >50% over two years. Whilst surface melting on the scale that preceded Larsen B collapse has historically been limited to the North of the Antarctic Peninsula, under future anthropogenic warming, more of Antarctica’s ice shelf area could become vulnerable to hydro-fracture.To quantify the role of ice shelf hydro-fracture in ice sheet response to warming, the PSU ice sheet model (PSUISM) incorporates a simple parameterisation of this process, as well as ice cliff failure following loss of buttressing. With its computationally tractable hydro-fracture parameterisation, PSUISM has been used to reproduce large long term Antarctic mass loss under periods of past warmth. It has also simulated high Antarctic contribution to future sea level. However, the break-up of Larsen B, which provides the observational basis for its hydro-fracture scheme, has been less well explored in PSUISM.We present a suite of high-resolution simulations of the Larsen B ice shelf and its tributary glaciers. We explore the role of hydro-fracture parameters and a range of climate boundary conditions in driving ice shelf collapse. We also compare modelled ice shelf retreat, and grounded ice response, to available observational data. Finally, we explore modifications to the simple hydro-fracture scheme that can better capture Larsen B shelf collapse.Ice shelf processes remain a key challenge in predicting future Antarctic ice sheet retreat. Despite advances in ice sheet modelling, capturing hydro-fracture in models capable of long integration times, at high resolution, remains a challenge. Our work explores how well the current approach in PSUISM captures the best observed ‘hydro-fracture’ driven ice shelf collapse, and how that impacts our understanding of existing projections.  
Disemination of air quality knowledge to the society through CAMS PL - Copernicus Atmosphere Monitoring Service National Colaboration Program.
Authors: Drzewiecki Piotr , Gienibor Aneta
Published: March 2024

We delve into the comprehensive approach employed by the CAMS PL - Copernicus Atmosphere Monitoring Service National Collaboration Program for disseminating air quality knowledge to society. The initiative encompasses outreach through various channels, primarily leveraging social media platforms and the organization's website. A crucial aspect of this dissemination strategy is rooted in insights from surveys conducted among diverse stakeholders, including non-profit organizations, local administration units, the scientific community, secondary school teachers and students.Specifically, this presentation sheds light on the program's utilization of Instagram and Facebook profiles as dynamic tools for engagement. The nuances of connecting with various demographics through these popular social media platforms are explored, emphasizing the adaptability and responsiveness required to convey air quality information effectively.This presentation aims to contribute to the broader discourse on effective science communication strategies, particularly in environmental awareness and education.
Shoreline Change Analysis After Construction of Coastal Structures in Wonpyeong-Chogok Beach by Satellite Image Process
Authors: Kim Eui Hyun , Lee Jung Lyul
Published: March 2024

As the number and quality of satellite data detecting the Earth increases, a significant number of research fields are using these images, providing increasingly interesting results that were previously unimaginable. In this study, we extract the coastline from satellite images captured over a long period of time and analyze how the location of the coastline has changed in time and space.Recently, many studies have attempted similar analyzes. However, the resolution of the image is low, so the results tend to be unreliable, as they often produce trend results of less than cm per year. Therefore, in this study, we first analyzed how reliable the trend results are depending on the amount of data, even if the resolution is low.We also present a method to obtain the location of the coastline from reference points fixed behind the coast by linearly fitting nearby coastline points to reduce the error of coastline points extracted from satellite images. This method obtains the coastline position as the distance to the intersection of the base line and the fitting line and obtains the coastline gradient as the angle of the fitting line.This method was applied to Wonpyeong-Chogok Beach located in the East Sea of the Korean Peninsula to analyze how the coastline has evolved over the past five years from 2019 to 2023, when coastal structures were built. On this beach, which has a total length of 2.9 km, three submerged detached breakwaters, two emerged detached breakwaters, and three groynes were built to reduce beach erosion. Reference points are located about 100 m behind the circular line that best fits the coastline, and the direction of base line is fixed to face the center of the fitting circle. Behind the emerged detached breakwater, the rate of change is up to 6.2m per year, and even in areas where structures have not yet been installed, there is a slight forward trend (0.4m/yr) due to the influence of beach nourishment. The standard deviation of the coastline position data for each base line ranges from 4.0m to 10.6m. Recently, Lim et al. (2022) presented the relationship between the standard deviation of the coastline data and sand grain size, and compared to the sand grain size results collected in the field, the grain size value was shown to be larger. The reason is that if the annual mean coastline is not maintained and continues to advance, the standard deviation increases. Considering this effect, the results are compared with observed sand gain size data. Therefore, it will be interesting to see how feasible it is to estimate the sand grain size from the analysis of long-term shoreline data obtained from satellite data, as in the results of this study.  ReferenceLim, C., Kim, T.-K., Kim, J.-B., and Lee, J.-L. (2022). A study on the influence of sand median grain size on the short-term recovery process of shorelines. Front. Mar. Sci. 9. doi: 10.3389/fmars.2022.906209
Conservation of World Heritage glacial landscapes in a changing climate: The Swiss Alps Jungfrau-Aletsch case
Authors: Bussard Jonathan , Reynard Emmanuel
Published: March 2024

Many glacial landscapes on all continents are inscribed on the World Heritage List. Due to climate change, most of the glaciers are retreating rapidly, thus questioning their Outstanding Universal Value (OUV). Ice loss could indeed reduce or modify the heritage values of the UNESCO World Heritage properties where glaciers are the core of the OUV and even question their inscription on the World Heritage List. In a future with fewer or without glaciers, at least two components of the OUV of World Heritage glacial landscapes could be affected: the aesthetic value (criterion vii), which could be reduced if glaciers disappear, and the geoheritage value (criterion viii), which is partly based on current glaciological processes that would no longer exist without ice.This presentation aims to clarify what constitute the heritage values of glacial landscapes and outlines how they could evolve in a future with less (or without) ice. For two sites in the UNESCO Swiss Alps Jungfrau-Aletsch property (the Great Aletsch Glacier and the Upper Lauterbrunnen Valley), we describe the evolution of the glacial landscape using a Past-Present-Future framework. We then evaluate the present and post-glacial heritage values according to criteria used in the literature on geomorphosites.We outline two main issues:1. The two sites are characterized by a very high palaeogeographical interest: the inherited glacial landforms around the Great Aletsch Glacier and Lake Oberhorn have allowed the reconstruction of Holocene glacial stages. In the future, the inherited landforms of high palaeogeographical interest and the para- and periglacial processes that develop in post-glacier conditions are likely to gain interest, while the dynamics of the glacier itself, which is an important part of the current geoscientific value, will decline and even be lost when the glacier disappears. As glaciers retreat, the geoscientific value will therefore depend more and more on the inherited glacial landforms, which allow the understanding of the Earth and climate history, and less and less on the glacier itself and its dynamics. As the inherited landforms can be fragile, are non-renewable and will become more central to the heritage value, their protection is an issue.2. The aesthetic value of glacial landscapes could decrease because of the disappearance of the glacier (landscape greying). One possible adaptation could be a shift from glacier tourism, which is mainly oriented towards the contemplation of an aesthetic landscape, to geotourism, where the understanding of landscape evolution is proposed to the public.