Author: Latest Results

Projections of precipitation extremes over the Volta Basin: insight from CanESM2 regional climate model under RCP 4.5 and 8.5 forcing scenarios

Latest Results

Abstract

Perturbations in extreme precipitation characteristics are investigated over the Volta Basin (VB) and its three subdomains (Sahel, Soudano-Sahel and Guinea Coast) for the early-21st (2030–2053) and mid-twenty-first centuries (2057–2080) under representative concentration pathways (RCPs) 4.5 and 8.5. Seven climate indices from the Expert Team on Climate Change Detection and Indices were selected to examine future extreme precipitation features. Owing to its performance over the West African sub region, CanESM2 model results were used with Global Precipitation Climatology Centre (GPCC v7) dataset serving as reference data. Results generally show lowering trends in extreme precipitation events over the VB. The declines in extremes were dominant in the Sahel and Soudano-Sahel zones with some degree of upsurges observed in the Guinea Coast. Spatially over the basin, wet spells (CWD) were projected to shorten under RCP 8.5 (~ 7–27 days/year) relative to RCP 4.5 (~ 8–30 days/year). Similar pattern was observed for dry spells (CDD) with ranges of ~ 64–198 days/year and ~ 61–186 days/year respectively for RCPs 4.5 and 8.5. As revealed, future alterations in precipitation events have the propensity to cause alternating drought or flood events. In this line, sustainable adaptation measures and coping strategies need to be devised in time to minimize the consequences of these events, particularly those on water resources availability and ecosystem functions and services.

Comparing the Clique Percolation algorithm to other overlapping community detection algorithms in psychological networks: A Monte Carlo simulation study

Latest Results

Abstract

In psychological networks, one limitation of the most used community detection algorithms is that they can only assign each node (symptom) to a unique community, without being able to identify overlapping symptoms. The clique percolation (CP) is an algorithm that identifies overlapping symptoms but its performance has not been evaluated in psychological networks. In this study, we compare the CP with model parameters chosen based on fuzzy modularity (CPMod) with two other alternatives, the ratio of the two largest communities (CPRat), and entropy (CPEnt). We evaluate their performance to: (1) identify the correct number of latent factors (i.e., communities); and (2) identify the observed variables with substantive (and equally sized) cross-loadings (i.e., overlapping symptoms). We carried out simulations under 972 conditions (3x2x2x3x3x3x3): (1) data categories (continuous, polytomous and dichotomous); (2) number of factors (two and four); (3) number of observed variables per factor (four and eight); (4) factor correlations (0.0, 0.5, and 0.7); (5) size of primary factor loadings (0.40, 0.55, and 0.70); (6) proportion of observed variables with substantive cross-loadings (0.0%, 12.5%, and 25.0%); and (7) sample size (300, 500, and 1000). Performance was evaluated through the Omega index, Mean Bias Error (MBE), Mean Absolute Error (MAE), sensitivity, specificity, and mean number of isolated nodes. We also evaluated two other methods, Exploratory Factor Analysis and the Walktrap algorithm modified to consider overlap (EFA-Ov and Walk-Ov, respectively). The Walk-Ov displayed the best performance across most conditions and is the recommended option to identify communities with overlapping symptoms in psychological networks.

Equity as a priority in EAT–Lancet-aligned food system transformations

Latest Results

Abstract

Food systems drive human and environmental change, reflect diverse cultural and ecological contexts, and, in their diversity, can bolster nutrition and planetary health. Ignoring structural inequities in food system transformations risks offsetting potential gains. We summarize current evidence on the context-dependent implications of EAT–Lancet goals and propose six priority areas to guide equitable food system transformations, targeting food and nutrition security, just sustainability and cultural diversity. Priority areas—namely, diverse and nutritious food access, food industry regulation, climate-resilient food production, localized, small-scale food systems, cultural diversity and social well-being—can be achieved through public, private and civil society action.

Traces of collisional and transtensional processes between the Carpathia and the European platform in the geoelectric image (NE Slovakia and SE Poland)

Latest Results

Abstract

We present the latest magnetotelluric models on profiles in the northeastern part of Slovakia and the southeastern part of Poland. These models are focused on deciphering the tectonic structures at the contact of the Inner Carpathians with the European Platform in this area. For the Inner Carpathian block, we propose the term Carpathia. Profile SA-01 shows shallower structures and the parallel MT-05 profile shows deeper structures. These models are also correlated with the seismic profile CEL-05. All results are compatible and show an original subduction-collisional structure, which was later replaced by a transpressive-transtensional one. The most striking structures are thick highly conductive subhorizontal zones in the middle crust and a tectonically controlled deep vertical conductive structure—the Carpathian conductive zone. Other significant structures, which also appear in the seismic section, are back thrusting of Flysch Belt and the Klippen Belt basement (Penninic crust) uplift.

Application of the MHVSR method for determining the location of landslide areas before geotechnical project proposal: a case study of Tortum Lake, Turkey

Latest Results

Abstract

Tortum Lake, in Turkey, which is a natural feature and a large landslide barrier lake, was formed due to a natural landslide disaster. In this context, areas with the potential to create landslides in Tortum Lake and the waterfall region are identified and displaced with zoning. Microtremor horizontal-to-vertical spectral ratio method and seismic refraction studies were used, and by considering the results, the areas with high landslide potential were determined. It aims to choose an effective study area by determining the areas with high landslide capability and revealing the boundaries of the geotechnical project. Areas with high landslide potential were compared with those where landslides have happened, and it showed that this method can be used for determining sliding risk before it happens. Results showed that regions with low VS30, combined with the slope, create the potential for landslides. Afterward, when the map of ground amplification values obtained from the microtremor data was reviewed, it was found that the physical properties of areas with high ground amplification values would be the same as those of areas with low VS30 values. When these two maps are reviewed, it is observed that areas with low VS30 values and high ground amplification values are in the same locations as those with high sliding potential. The correct determination of the geotechnical project work area is important both to draw attention to the right area to be designed and to avoid wasting unnecessary time and money on unnecessary areas.

Pre-Pandemic and Recent Oral and Medical Health Care Utilization among Young American Indian Children and Their Caregivers

Latest Results

Abstract

Children from diverse ethnic groups are at significantly increased risk for dental caries. In particular, American Indian (AI) children have the highest incidence of detal caries of any ethnic group. The COVID-19 pandemic dramatically restricted health care access, including preventive oral health care. Given this context, it is unclear whether or not preventive oral health care for AI children has resumed since lockdown. To address this question, we surveyed adult AI caregivers (N = 152) of children aged 0–5 years, assessing recent (12-month) and pre-COVID (for caregivers of children aged 3–5 years) preventive oral and medical health services. We also examined medical health care access and utilization among caregivers. Among children aged 3–5 years old, both pre-pandemic and past year medical care utilization were generally high (80 and 90%, respectively) as was any oral health care utilization (64 & 78%, respectively). Oral health check-ups were more common over the last year (62%) compared to pre-COVID (44%). Recent health care utilization among children 1–5 years old in this sample were generally comparable to national estimates, except for higher reported preventive medical care (99% vs. 87.6%, respectively) and higher preventive oral care (96% vs. 59.6%, respectively). More caregivers reported delaying or foregoing needed health care due to COVID (28–38%) versus due to cost (8–17%). In this survey of AI caregivers, recent child preventive health care utilization was high, and changes in utilization following the lockdown phases of the pandemic were comparable for oral and medical health care.

Structure and functional implications of photoreceptive systems in non-marine ostracods: a review

Latest Results

Abstract

Ostracods are small, bivalved crustaceans living in all types of aquatic habitats. All non-marine species belong to the order Podocopida. They usually possess a simple optical system composed of three eyecups called naupliar eye. Phylogenetic data and morphological characteristics support the homology of naupliar eyes between ostracods and other crustacean groups. The photoreceptive system is formed by several specialised cells and can be approximated by a lens-mirror optical apparatus. In some cases, a transparent area of the calcitic carapace can form an additional lens. The visual stimuli are processed by the protocerebrum, possibly via monoaminergic neurons. The presence or absence of one or more specialised cells influence the function of the eyes, and, most likely, their evolution or loss are associated with the adaptation to different habitats. Podocopid ostracods may express long wavelength-sensitive rhabdomeric opsins and may possess nonvisual opsins. The few ethological experiments so far conducted demonstrate that non-marine ostracods might be capable of associative learning when trained with light or specific light wavelengths. This work will provide an overview of what is known and what remains to be further investigated about vision and how light cues affect the behaviour in non-marine ostracods.

NASH triggers cardiometabolic HFpEF in aging mice

Latest Results

Abstract

Both heart failure with preserved ejection fraction (HFpEF) and non-alcoholic fatty liver disease (NAFLD) develop due to metabolic dysregulation, has similar risk factors (e.g., insulin resistance, systemic inflammation) and are unresolved clinical challenges. Therefore, the potential link between the two disease is important to study. We aimed to evaluate whether NASH is an independent factor of cardiac dysfunction and to investigate the age dependent effects of NASH on cardiac function. C57Bl/6 J middle aged (10 months old) and aged mice (24 months old) were fed either control or choline deficient (CDAA) diet for 8 weeks. Before termination, echocardiography was performed. Upon termination, organ samples were isolated for histological and molecular analysis. CDAA diet led to the development of NASH in both age groups, without inducing weight gain, allowing to study the direct effect of NASH on cardiac function. Mice with NASH developed hepatomegaly, fibrosis, and inflammation. Aged animals had increased heart weight. Conventional echocardiography revealed normal systolic function in all cohorts, while increased left ventricular volumes in aged mice. Two-dimensional speckle tracking echocardiography showed subtle systolic and diastolic deterioration in aged mice with NASH. Histologic analyses of cardiac samples showed increased cross-sectional area, pronounced fibrosis and Col1a1 gene expression, and elevated intracardiac CD68+ macrophage count with increased Il1b expression. Conventional echocardiography failed to reveal subtle change in myocardial function; however, 2D speckle tracking echocardiography was able to identify diastolic deterioration. NASH had greater impact on aged animals resulting in cardiac hypertrophy, fibrosis, and inflammation.

Are impacts of the invasive alien plant Crassula helmsii mediated by detritus? A litter experiment in a temperate pond

Latest Results

Abstract

Because of the high growth rates often achieved by invasive alien macrophytes, their establishment in recipient ecosystems may alter the abundance and composition of litter entering detrital pathways, representing a significant—but often overlooked—ecological effect of these invasions. Crassula helmsii (Kirk) Cockayne (New Zealand pygmyweed) is an invasive alien macrophyte, notorious for its profuse growth in invaded waterbodies. C. helmsii is perennial and often forms dense stands, producing abundant detritus. To investigate whether some of C. helmsii’s impacts are mediated by this detritus, we conducted an 85-day litterbag experiment comparing decomposition of C. helmsii with that of Callitriche stagnalis Scop. (water-starwort), a commonly co-occurring native macrophyte. Macroinvertebrate assemblage composition was comparable between macrophyte species throughout the experiment, but shifted as plants decayed. Litterbags were initially dominated by the invasive shredder Crangonyx pseudogracilis Bousfield, 1958 and later by Euglesa casertana (Poli, 1791), an interstitial suspension feeder. C. helmsii litter decomposed more slowly, with proportionally less invertebrate-mediated breakdown, but was ultimately colonised by more abundant macroinvertebrates, including more C. pseudogracilis. Decomposition may be slowed by C. helmsii’s high carbon: nitrogen ratio. These results suggest that C. helmsii invasion may impact macroinvertebrate assemblages via the production of long-lasting and relatively unpalatable detritus.

A Study on the Effects of Using the 6E Model and a Robot Teaching Assistant on Junior High School Students’ STEM Knowledge, Learning Motivation, and Hands-on Performance

Latest Results

Abstract

The integration of education and robotics has emerged as a crucial development in the technological landscape. This study focuses on the use of a robot teaching assistant to enhance the learning efficiency of 8th-grade students in hands-on STEM activities centered around the theme of “Smart City.” It explores the impact of educational robots on students' learning outcomes and their development of hands-on skills through diverse learning methods. Conducted over 12 weeks with 103 participants, the study employed a quasi-experimental design. Students were split into two groups: The Experimental Group (EG), using the 6E model with robot teaching assistants, and the Control Group (CG), using only the 6E model. The analysis of covariance revealed that the EG exhibited superior performance in STEM knowledge, motivation, and hands-on skills compared to the CG. Further analysis indicated that learning motivation significantly influenced hands-on performance in the EG, particularly in high-scoring subgroups. The findings suggest that combining the 6E model with educational robots effectively enhances STEM learning and student engagement. Educational robots as teaching assistants not only aid in knowledge acquisition but also significantly boost students' motivation and hands-on skill development. This implies a promising direction for integrating advanced technology in educational practices to foster more effective learning environments.