bluuebunny/crossref_metadata_2025 huggingface dataset:
Gust Modeling with State-of-the-Art Computational Fluid Dynamics (CFD) Software and Its Influence on the Aerodynamic Characteristics of an Unmanned Aerial Vehicle
Authors: Frant Michał , Kachel Stanisław , Maślanka Wojciech
Published: September 2023

The aim of this article is to propose methods for obtaining the aerodynamic characteristics of a flying object in a turbulent atmosphere. This article presents static aerodynamic characteristics of an unmanned aerial vehicle (UAV), which have been obtained during experimental examinations and during numerical calculations. The results have been compared with each other in order to validate the numerical model and methods. The method for modeling gusts using state-of-the-art CFD software (i.e., ANSYS Fluent Release 16.2) has been proposed and applied to obtain the aerodynamic characteristics of a UAV including during gusts. Two cases have been analyzed. In the first case, a downburst was modeled. In the second case, a single oblique gust was modeled (i.e., changing the angle of attack and the angle of sideslip), that had a complicated time course in regard to its velocity. Although this article is focused on the assessment of the vulnerability of a UAV model to gusts, the practical implications of the proposed methodology are applicable to a wide selection of objects, including wind turbines.
Energetic Assessment of SCWG Experiments with Reed Canary Grass and Ethanol Solution on Laboratory and Pilot Scale
Authors: Dutzi Julian , Boukis Nikolaos , Sauer Jörg
Published: September 2023

The energetic assessment of biomass conversion processes is important for evaluating their application potential. Process energy efficiency is often evaluated based on simulation results for processes under idealized conditions. The present work uses data from a laboratory plant to perform an evaluation of the supercritical water gasification (SCWG). For this purpose, experiments were conducted with two types of feedstock, Reed Canary Grass and ethanol. Under the present lab-plant configuration, a cold gas efficiency of up to 79% could be reached, which is comparable to the gasification of biomass in fluidized-bed gasifiers or entrained-flow gasifiers. Based on the obtained data on the produced substances and their distribution, a scale up to pilot plant size was conducted. A model was derived from the available data to energetically assess different SCWG plant sizes based on real laboratory results. This model can be transferred to other feedstocks and other process designs to approximate the optimal size for the used biomass feedstock. The importance of heat recuperation in this process is described in detail based on pilot-scale data.
Simple and Accurate Model of Thermal Storage with Phase Change Material Tailored for Model Predictive Control
Authors: Vrbanc Filip , Vašak Mario , Lešić Vinko
Published: September 2023

Thermal heat storage is becoming important in systems with renewable energy sources. Their largest benefit is smoothing the intermittent production and reduction in the site peak demand. The advantages of thermal energy storage with phase-change material are storing energy at a lower temperature for reduction in thermal losses, and enabling energy transfer at a constant temperature, which reduces the risk of equipment damage. In this paper, a low-order model of latent thermal energy storage, derived in a state-space form by using the mixed logical dynamical approach, is proposed. The model is compared to a stratified model and shows significant improvements of physical accuracy and execution time. Finally, a model predictive control algorithm suited for the real case study is designed, implemented and compared to classical rule-based control. The obtained results show significant energy savings of 8.43%, and improvements in user comfort and equipment duration.
Changing Electricity Tariff—An Empirical Analysis Based on Commercial Customers’ Data from Poland
Authors: Ząbkowski Tomasz , Gajowniczek Krzysztof , Matejko Grzegorz , Brożyna Jacek , Mentel Grzegorz , Charytanowicz Małgorzata , Jarnicka Jolanta , Olwert Anna , Radziszewska Weronika
Published: September 2023

Nearly 60% of commercial customers are connected to a low-voltage network in Poland with a contractual capacity of more than 40 kW and are assigned a fixed tariff with flat prices for the whole year, no matter the usage volume. With smart meters, more data about how businesses use energy are becoming available to both energy providers and customers. This enables innovation in the structure and type of tariffs on offer in the energy market. Customers can explore their usage patterns to choose the most suitable tariff to benefit from lower prices and thus generate savings. In this paper, we analyzed whether customers’ electricity usage matched their optimal tariff and further investigated which of them could benefit or lose from switching the tariff based on the real dataset with the hourly energy readings of 1212 commercial entities in Poland recorded between 2016 and 2019. Three modelling approaches, i.e., the k-nearest neighbors, classification tree and random forest, were tested for optimal tariff classification, while for the benchmark, we used a simple approach, in which the tariff was proposed based on the customers’ previous electricity usage. The main findings from the research are threefold: (1) out of all the analyzed entities, on average, 76% of them could have benefited from the tariff switching, which suggests that customers may not be aware of the tariff change benefits, or they had chosen a tariff plan that was not tailored to them; (2) a random forest model offers a viable approach to accurate tariff classification; (3) the policy implication from the research is the need to increase the customers’ awareness about the tariffs and propose reliable tools for selecting the optimal tariff.
Study on the Life Cycle Assessment of Automotive Power Batteries Considering Multi-Cycle Utilization
Authors: Liu Yongtao , Zhang Chunmei , Hao Zhuo , Cai Xu , Liu Chuanpan , Zhang Jianzhang , Wang Shu , Chen Yisong
Published: September 2023

This article utilizes the research method of the Life Cycle Assessment (LCA) to scrutinize Lithium Iron Phosphate (LFP) batteries and Ternary Lithium (NCM) batteries. It develops life cycle models representing the material, energy, and emission flows for power batteries, exploring the environmental impact and energy efficiency throughout the life cycles of these batteries. The life cycle assessment results of different power battery recycling process scenarios are compared and analyzed. This study focuses on retired LFP batteries to assess the environmental and energy efficiency during the cascade utilization stage, based on a 50% Single-Cell Conversion Rate (CCR). The findings of the research reveal that, in terms of resource depletion and environmental emission potential, LFP batteries exhibit lower impacts compared to NCM batteries. The use of hydrometallurgy in recovering LFP power batteries leads to minimal life cycle resource consumption and environmental emission potential. During the cascade utilization stage of LFP batteries, significant benefits are noted, including a 76% reduction in mineral resource depletion (ADP e) and an 83% reduction in fossil energy depletion (ADP f), alongside notable reductions in various environmental impact factors. Simultaneously, considering the sensitivity of life cycle assessment indicators and their benefit percentages to different CCRs, it is observed that ODP exhibits the highest sensitivity to CCR changes, while evaluation indicators such as HTP, AP, and GWP show relatively lower sensitivity. This study can provide an effective reference for the establishment of an energy saving and emission reduction evaluation system of power batteries.
On-Board Fuel Consumption Meter Field Testing Results
Authors: Tapak Peter , Kocur Michal , Matej Juraj
Published: September 2023

This paper aims to investigate and compare the fuel consumption data obtained from on-board fuel consumption meters (OBFCMs) from approximately 1000 vehicles through field testing. Furthermore, this research aims not only to compare the OBFCM readings but also to juxtapose them against the fuel consumption specifications provided by the respective vehicle manufacturers. To collect data, a cost-effective on-board diagnostics (OBD) reader and a user-friendly mobile app were employed, providing an accessible and efficient method for fuel consumption analysis. Field testing involved a diverse range of vehicles, covering various makes, models, and years of production. The OBCFM readings were recorded over a 9-month period, probably capturing a wide range of driving conditions and patterns. In order to ensure the reliability of the OBCFM readings, the fuel consumption measurements obtained from the manufacturers specifications were utilized as a reference benchmark. Preliminary data analysis indicates that there are noticeable variations in the fuel consumption data obtained from the OBCFM and the manufacturer specifications. These differences can be attributed to various factors. The novelty of the presented data lies in using a new feature implemented in EU cars since 2019. The study capitalizes on this feature, allowing for the collection of data from a broad spectrum of vehicles throughout the country under genuine driving conditions.
A Review on the Fundamental Properties of Sb2Se3-Based Thin Film Solar Cells
Authors: Bosio Alessio , Foti Gianluca , Pasini Stefano , Spoltore Donato
Published: September 2023

There has been a recent surge in interest toward thin film-based solar cells, specifically new absorber materials composed by Earth-abundant and non-toxic elements. Among these materials, antimony selenide (Sb2Se3) is a good candidate due to its peculiar properties, such as an appropriate bandgap that promises a theoretical maximum power conversion efficiency of 33% and an absorption coefficient of around 105 cm−1, enabling its use as a thin film absorber layer. However, charge carrier transport has been revealed to be problematic due to its cumbersome structure and the lack of a doping strategy. In this work, we aim to provide a clear picture of the state-of-the-art regarding research on Sb2Se3-based solar cells and its prospects, from the successful achievements to the challenges that are still to be overcome. We also report on the key parameters of antimony selenide with a close focus on the different characteristics associated with films grown from different techniques.
Assessing the Energy Efficiency Gains and Savings in China’s 2060 Carbon-Neutral Plan
Authors: Zhang Chong , Mauleón Ignacio
Published: September 2023

At the end of 2020, the Chinese government announced the pledge to become carbon neutral in the year 2060. Simultaneously, quality growth objectives were established, which were environmentally friendly and promoted the health and wellbeing of the population. The first objective of this study is to assess the gains in energy efficiency and the savings in energy demand that this commitment implies. Secondly, the feasibility of achieving these objectives of savings and efficiency increases is discussed based on an international analysis. The method is based on a quantitative estimate of the primary energy demand throughout the period from 1965 up to the year 2060. For this purpose, long historical series taken from reliable international sources are analyzed. The methodology applied to estimate and project future energy demand is new and based on several steps: The first consists of analyzing the trends of the series and estimating the relationships between them using a robust procedure. Secondly, equilibrium relationships are estimated, which avoids the eventual instabilities involved in the estimation of dynamic models. The third characteristic is based on the bootstrap, estimating and simulating the model by selecting random samples of different sizes from the available dataset. The simulations generate a complete probability distribution for the expected energy demand, which also allows for carrying out a risk analysis, assessing the risk of the demand becoming significantly larger than the expected average. The first result obtained is that the primary energy demand forecast for 2060 is much higher than the demand of the official forecasts by almost three times. However, taking into account the objective to replace 85% of fossil sources with renewables, this discrepancy is greatly reduced and becomes approximately 50% higher than the official forecast. If the savings analyzed in relevant international references are accounted for, then an additional reduction of even up to 40% of this demand could be achieved, so that the final demand would fall further, close to official forecasts. The main and final conclusion is that although the objective of making the Chinese economy carbon neutral by 2060 is feasible, it implies a radical transformation that will necessarily require a determined and unwavering political commitment throughout the entire period considered.
Locating Potential Run-of-River Hydropower Sites by Developing Novel Parsimonious Multi-Dimensional Moving Window (PMMW) Algorithm with Digital Elevation Models
Authors: Bhagwat Ninad , Zhou Xiaobing
Published: September 2023

We developed a Parsimonious Multi-dimensional Moving Window (PMMW) algorithm that only requires Digital Elevation Model (DEM) data of a watershed to efficiently locate potentially optimal hydropower sites. The methodology requires only open source DEM data; therefore, it can be used even in remotest watersheds of the world where in situ measurements are scarce or not available at all. We used three parameters in this algorithm, and tested the method using the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and the Shuttle Radar Topography Mission (SRTM) derived DEMs. Our case study on the Morony Watershed, Montana, USA shows that (1) along with 6 out of the 7 existing hydropower plants being successfully located, 12 new potential hydropower sites were also identified, using a clearance of 1 km, diversion of 90 m, and Hydropower Index (HI) threshold of 109 m as the criteria. For the 12 new potential hydropower sites, 737.86 Megawatts (MW) ± 84.56 MW untapped hydropower potential in the Morony Watershed was also derived; (2) SRTM DEM is more suitable for determining the potential hydropower sites; (3) although the ASTER and SRTM DEMs provide elevation data with high accuracy, micro-scale elevation differences between them at some locations may have a profound impact on the HI.
Towards a Carbon Accounting Framework for Assessing the Benefits of Biogenic Wood Carbon to Net Zero Carbon Targets
Authors: Arodudu Oludunsin , Therasme Obste , Volk Timothy , Malmsheimer Robert , Crovella Paul , Germain René , Kloster Danielle , Kumar Deepak
Published: September 2023

Carbon stored in harvested wood products (HWPs) can play an important role in climate change mitigation and needs to be accounted for accurately and consistently. This study reviewed the features of previous HWP carbon accounting frameworks and discussed potential improvements for a more complete assessment of all HWP contributions to net zero carbon targets at subnational levels. The basic features include the components, the methods, the approaches, and the modeling principles. A key recommendation is to expand previous HWP C accounting framework components to include other climate change mitigation benefits such as local or regional substitution effects (i.e., material replacement, fossil fuel displacement effects, energy efficiency gains, recycling effects, and cascading use impacts) of all produced and consumed HWPs. Another area for improvement is the need for subnational unit-specific activity data and conversion factors. Adopting variants of the domestic origin-stock change approach will also help account for relevant production and consumption activities within the subnational unit. These recommendations will enhance the accuracy and/or precision of HWP accounting frameworks at the subnational level and help capture all potential benefits of HWPs as a carbon sink for climate change mitigation and a valuable contributor to subnational net zero carbon targets.
Expansion of Treeline in North China and Its Relationship with Altitude Sensitivity Gradient of Larix gmelinii
Authors: Li Bo , Liu Binhui , Henderson Mark , Zhou Wanying , Chen Mingyang
Published: September 2023

As the climate has warmed, alpine treelines have moved to higher altitudes and the responses of tree growth to different climate factors have changed. We collected dendrochronologies of Larix gmelinii at different elevations on the Dabai Mountain, the highest peak in northeastern China’s Greater Khingan range, to measure the sensitivity and stability of radial growth over time. We found that the treeline has moved upslope since 1970. From the mid-1980s, radial growth increased in the treeline ecotone but decreased in the subtimberline forest, an example of “growth divergence” under warming conditions: increases in the previous October’s maximum temperatures promoted growth at higher altitudes but inhibited it at lower altitudes. The treeline ecotone appears to be more sensitive to climate change, with the effects on tree growth of different climate indicators varying by altitude in linear or U-shaped relationships. As warming continues, the management of boreal forests needs to consider the changing potential for tree growth and carbon sequestration capacity in relation to changing site conditions.
The Effect of Age on the Evolution of the Stem Profile and Heartwood Proportion of Teak Clonal Trees in the Brazilian Amazon
Authors: Santos Mario Lima dos , Miguel Eder Pereira , Biali Leonardo Job , Souza Hallefy Junio de , Santos Cassio Rafael Costa dos , Matricardi Eraldo Aparecido Trondoli
Published: September 2023

Stem profile modeling is crucial in the forestry sector, particularly for commercially valuable species like teak (Tectona grandis Linn F.), whose value depends on its stem dimensions, heartwood proportion, and age. We proposed a nonlinear mixed-effect model to describe the evolution of the stem and heartwood profiles of clonal teak trees with ages between 4 and 12 years in the Brazilian Amazon. Tapering models were used to estimate the bark, bark-free, and heartwood diameters. Dummy variables were included in each tapering model to estimate each type of diameter and enable compatibility. We used mixed models with age as a random effect in order to improve the accuracy. The Demaerschalk model provided the most accurate and compatible estimates for all three types of stem diameter. Also, age as a random effect significantly improved the model’s accuracy by 7.2%. We observed a progressive increase in the heartwood proportion (14% to 34%) with advancing age, while the proportions of bark (23% to 20%) and sapwood (63% to 45%) showed inverse behavior. The growth rate of the heartwood differed from that of the bark volume, emphasizing the importance of considering the age of heartwood maximization when determining the cutting cycle of the species.
Review of Managing Soil Organic C Sequestration from Vegetation Restoration on the Loess Plateau
Authors: Yang Yang , Sun Hui , Zhang Pingping , Wu Fan , Qiao Jiangbo , Li Tongchuan , Wang Yunqiang , An Shaoshan
Published: September 2023

China’s Loess Plateau is both the largest and deepest loess deposit in the world, and it has long been one of the most severely eroded areas on Earth. With the implementation of the Grain-for-Green Project in 1999, the Loess Plateau has become the most successful ecological restoration zone, and soil organic carbon (SOC) sequestration has greatly increased. However, little is known about the balance of SOC sequestration and vegetation restoration on the Loess Plateau. Thus, this review focused on the SOC sequestration from vegetation restoration in this region. Firstly, the current situations and principal aspects of vegetation restoration processes were reviewed, and the effects of vegetation restoration on SOC sequestration were summarized. Secondly, based on the new technologies and methods for soil carbon (C) sequestration, the mechanism of soil microbial C sequestration was described from the molecular level of genes, and some management measures for SOC sequestration were summarized. Finally, we pointed out the main directions in C sequestration mechanisms for vegetation restoration depending on the basic process of the C cycle, which should integrate into physics, chemistry, and biology. Overall, this review will help us understand the SOC sequestration function and the ecological benefits of vegetation restoration on the Loess Plateau.
Seasonal Dynamics of Flux Footprint for a Measuring Tower in Southern Taiga via Modeling and Experimental Data Analysis
Authors: Sogachev Andrey , Varlagin Andrej
Published: September 2023

This paper reports on the location of sources contributing to a point flux measurement in the southern taiga, Russia. The measurement tower is surrounded by a coniferous forest with a mean aerodynamically active height of 27 m (h). Aerodynamical parameters of the forest, such as displacement height d and aerodynamic roughness z0, derived from wind speed profile measurements for 2017–2019, were used to estimate the seasonal and daily behavior of the flux footprint. Two analytical footprint models driven by d and z0 were used to estimate the footprint for canopy sources. The Lagrangian simulation (LS) approach driven by flow statistics from measurements and modeling was used to estimate the footprint for ground-located sources. The Flux Footprint Prediction (FFP) tool for assessing canopy flux footprint applied as the option in the EddyPro v.7 software was inspected against analytical and LS methods. For model comparisons, two parameters from estimated footprint functions were used: the upwind distance (fetch) of the peak contribution in the measured flux (Xmax) and the fetch that contributed to 80% of the total flux (CF80). The study shows that Xmax varies slightly with season but relies on wind direction and time of day. All methods yield different Xmax values but fall in the same range (60–130 m, around 2–5 h); thus, they can estimate the maximum influence distance with similar confidence. The CF80 values provided by the FFP tool are significantly lower than the CF80 values from other methods. For instance, the FFP tool estimates a CF80 of about 200 m (7 h), whereas other methods estimate a range of 600–1100 m (25–40 h). The study emphasizes that estimating the ground source footprint requires either the LS method or more complex approaches based on Computational Fluid Dynamics (CFD) techniques. These findings have essential implications in interpreting eddy-flux measurements over the quasi-homogeneous forest.
Optimization of Alkaline Hydrogen Peroxide Pretreatment and Enzymatic Hydrolysis of Wheat Straw for Enhancing Sugar Yields
Authors: Zhang Hui , Wu Junhui
Published: September 2023

Optimization of alkaline hydrogen peroxide (AHP) pretreatment and enzymatic hydrolysis of wheat straw (WS) was carried out to enhance fermentable sugar yields with the use of glucose and xylose yields from the pretreated WS as responses. In the first step, variables including temperature, hydrogen peroxide concentration and time during pretreatment were detected to have significant effects on the sugar yields. The results indicate that maximal sugar yields could be obtained while the WS was pretreated using 71 g/L hydrogen peroxide solution with 200 g/L of solid loading at 50 °C for 7.6 h. The corresponding cellulose recovery, hemicellulose recovery and lignin removal were 97.5%, 84.3% and 75.0%, respectively. In the second step, enzymatic hydrolysis of the pretreated WS was optimized. The results show that the reaction time, enzyme loading and biomass loading during enzymatic hydrolysis also had significant effects on the sugar yields. The final maximum yields of glucose (552.7 mg/gds (mg/g dry substrate)) and xylose (223.6 mg/gds) could be obtained while enzymatic hydrolysis was carried out at 50 °C for 37.0 h using 10.8 FPU/gds (filter paper activity unit per gram dry substrate) of enzyme loading, 88 g/L of biomass loading and 0.3% (w/v) of Tween-80. The corresponding cellulose conversion and hemicellulose conversion were 94.0% and 83.5%, respectively.
Exploring the Factors Affecting Countries’ Adoption of Blockchain-Enabled Central Bank Digital Currencies
Authors: Mohammed Medina Ayta , De-Pablos-Heredero Carmen , Montes Botella José Luis
Published: September 2023

Central bank-issued digital currencies have sparked significant interest and are currently the subject of extensive research, owing to their potential for rapid settlement, low fees, accessibility, and automated monetary policies. However, central bank digital currencies are still in their infancy and the levels of adoption vary significantly between nations, with a few countries seeing widespread adoption. We used partial least squares structural equation modeling to investigate the nonlinear relationship between key national development indicators and central bank digital deployment across 67 countries. We explore the technological, environmental, legal, and economic factors that affect central bank digital currency adoption by country. We found a statistically significant and positive correlation between countries’ central bank digital currency adoption status and a country’s level of democracy and public confidence in governance, and a negative association between regulatory quality and income inequality. There was no significant association between countries’ central bank digital currency adoption status and their level of network readiness, foreign exchange reserves, and sustainable development goal rank. Thus, we posit that a country that is highly democratic and has good governance adopts central bank digital currencies more readily than others. Based on our findings, we suggested areas for additional research and highlighted policy considerations related to the wider adoption of central bank digital currency.
Evaluation of the Viral Diversity of Artemia Cysts from Saline Lakes in Kazakhstan Using Viral Metagenomics Analysis
Authors: Kumar Marat , Karamendin Kobey , Mazhibayeva Zhanara , Kassymbekov Yermukhammet , Sabyrzhan Temirlan , Isbekov Kuanysh , Assylbekova Saule , Kydyrmanov Aidyn
Published: September 2023

Artemia (brine shrimp) holds significant value as a live feed for larval fish and crustaceans, owing to their distinctive dietary requirements. However, it is vital to acknowledge that Artemia also carries potential risk as a vector of infection. We conducted a metagenomic analysis to explore the virome present in Artemia cysts collected from inland salt lakes across four distinct regions in Kazakhstan. This study identified the presence of dsDNA phages and RNA virus sequences, with a predominant representation from the Reoviridae, Nodaviridae, Dicistroviridae, Picornaviridae, Astroviridae, Tombusviridae, and Solemoviridae families. In general, this study has significantly enhanced our understanding of the virome of Artemia cysts in the saline lakes of Kazakhstan; however, the interactions between these putative viruses and brine shrimp and other aquatic animals need further research.
Analysis of Core Annular Flow Behavior of Water-Lubricated Heavy Crude Oil Transport
Authors: Jadidi Salim , Moolya Shivananda , Satheesh Anbalagan
Published: September 2023

A possible method for fluid transportation of heavy oil through horizontal pipes is core annular flow (CAF), which is water-lubricated. In this study, a large eddy simulation (LES) and a sub-grid-scale (SGS) model are used to examine CAF. The behavior of heavy oil flow through turbulent CAF in horizontal pipes is numerically investigated. The Smagorinsky model is utilized to capture small-scale unstable turbulent flows. The transient flow of oil and water is first separated under the behavior of the core fluid. Two different conditions of the horizontal pipes, one with sudden expansion and the other with sudden contraction, are considered in the geometry to investigate the effects of different velocities of oil and water on the velocity distribution, pressure drop, and volume fraction. The model was created to predict the losses that occur due to fouling and wall friction. According to the model, increasing water flow can reduce fouling. Additionally, the water phase had an impact on the CAF’s behavior and pressure drop. Also, the increased stability in the CAF reduces the pressure drop to a level that is comparable to water flow. This study demonstrated that a very viscous fluid may be conveyed efficiently utilizing the CAF method.
Modeling and Initialization of Nonlinear and Chaotic Fractional Order Systems Based on the Infinite State Representation
Authors: Trigeassou Jean-Claude , Maamri Nezha
Published: September 2023

Based on the infinite state representation, any linear or nonlinear fractional order differential system can be modelized by a finite-dimension set of integer order differential equations. Consequently, the recurrent issue of the Caputo derivative initialization disappears since the initial conditions of the fractional order system are those of its distributed integer order differential system, as proven by the numerical simulations presented in the paper. Moreover, this technique applies directly to fractional-order chaotic systems, like the Chen system. The true interest of the fractional order approach is to multiply the number of equations to increase the complexity of the chaotic original system, which is essential for the confidentiality of coded communications. Moreover, the sensitivity to initial conditions of this augmented system generalizes the Lorenz approach. Determining the Lyapunov exponents by an experimental technique and with the G.S. spectrum algorithm provides proof of the validity of the infinite state representation approach.
Factors Influencing the Maturation and Developmental Competence of Yak (Bos grunniens) Oocytes In Vitro
Authors: Mo Luoyu , Ma Jun , Xiong Yan , Xiong Xianrong , Lan Daoliang , Li Jian , Yin Shi
Published: September 2023

The yak (Bos grunniens) is a unique breed living on the Qinghai–Tibet Plateau and its surrounding areas, providing locals with a variety of vital means of living and production. However, the yak has poor sexual maturity and low fertility. High-quality mature oocytes are the basis of animal breeding technology. Recently, in vitro culturing of oocytes and embryo engineering technology have been applied to yak breeding. However, compared to those observed in vivo, the maturation rate and developmental capacity of in vitro oocytes are still low, which severely limits the application of in vitro fertilization and embryo production in yaks. This review summarizes the endogenous and exogenous factors affecting the in vitro maturation (IVM) and developmental ability of yak oocytes reported in recent years and provides a theoretical basis for obtaining high-quality oocytes for in vitro fertilization and embryo production in yaks.
Detection of Cancer-Associated Gene Mutations in Urinary Cell-Free DNA among Prostate Cancer Patients in South Africa
Authors: Temilola Dada Oluwaseyi , Wium Martha , Paccez Juliano , Salukazana Azola Samkele , Rotimi Solomon O. , Otu Hasan H. , Carbone Giuseppina M. , Kaestner Lisa , Cacciatore Stefano , Zerbini Luiz Fernando
Published: September 2023

Prostate cancer (PCa) is the most common cause of cancer death among African men. The presence of tumor-specific variations in cell-free DNA (cfDNA), such as mutations, microsatellite instability, and DNA methylation, has been explored as a source of biomarkers for cancer diagnosis. In this study, we investigated the diagnostic role of cfDNA among South African PCa patients. We performed whole exome sequencing (WES) of urinary cfDNA. We identified a novel panel of 31 significantly deregulated somatic mutated genes between PCa and benign prostatic hyperplasia (BPH). Additionally, we performed whole-genome sequencing (WGS) on matching PCa and normal prostate tissue in an independent PCa cohort from South Africa. Our results suggest that the mutations are of germline origin as they were also found in the normal prostate tissue. In conclusion, our study contributes to the knowledge of cfDNA as a biomarker for diagnosing PCa in the South African population.
A Redesigned Method for CNP-Synchronized In Vitro Maturation Inhibits Oxidative Stress and Apoptosis in Cumulus-Oocyte Complexes and Improves the Developmental Potential of Porcine Oocytes
Authors: Lu Jinlun , Guo Min , Wang Xiaodong , Wang Rui , Xi Guangyin , An Lei , Tian Jianhui , Chu Meiqiang
Published: September 2023

In vitro embryo production depends on high-quality oocytes. Compared with in vivo matured oocytes, in vitro oocytes undergo precocious meiotic resumption, thus compromising oocyte quality. C-type natriuretic peptide (CNP) is a follicular factor maintaining meiotic arrest. Thus, CNP-pretreatment has been widely used to improve the in vitro maturation (IVM) of oocytes in many species. However, the efficacy of this strategy has remained unsatisfactory in porcine oocytes. Here, by determining the functional concentration and dynamics of CNP in inhibiting spontaneous meiotic resumption, we improved the current IVM system of porcine oocytes. Our results indicate that although the beneficial effect of the CNP pre-IVM strategy is common among species, the detailed method may be largely divergent among them and needs to be redesigned specifically for each one. Focusing on the overlooked role of cumulus cells surrounding the oocytes, we also explore the mechanisms relevant to their beneficial effect. In addition to oocytes per se, the enhanced anti-apoptotic and anti-oxidative gene expression in cumulus cells may contribute considerably to improved oocyte quality. These findings not only emphasize the importance of screening the technical parameters of the CNP pre-IVM strategy for specific species, but also highlight the critical supporting role of cumulus cells in this promising strategy.
Fruit Quality of Several Strawberry Cultivars during the Harvest Season under High Tunnel and Open Field Environments
Authors: Patel Hiral , Taghavi Toktam , Samtani Jayesh B.
Published: September 2023

Parameters such as titratable acids (TA), total soluble solids (TSS), and their ratio (TSS/TA) are critical in determining strawberry fruit quality and the value of new cultivars. Ten strawberry cultivars were evaluated in two environments (open field and high tunnel) in the city of Virginia Beach. The objective was to evaluate the fruit quality characteristics (total soluble solids, titratable acidity TA, and total anthocyanin content) of newer strawberry cultivars grown in the annual hill plasticulture systems in coastal Virginia climatic conditions. Another objective was to measure the correlation between TA and a new digital meter (pocket acidity meter; PAM). Fruits were harvested weekly and TSS was measured using a refractometer. Acidity was measured using the pocket acidity meter and titratable acidity by a single sample titrimeter. Genetics significantly affected total anthocyanin content, TSS, TA, and acidity. The effect of the environments (high tunnel and open field) was not significant on TSS but significant on total anthocyanin content, TA, and acidity. “Flavorfest” had the highest and “Sweet Ann” the lowest anthocyanin content, TSS, and TA among the cultivars. The acidity (PAM data) showed a different level of correlation than TA, with a higher correlation for the open field than the high tunnel. On average, when outliers were removed, there was a regression of TA = 2.22(PAM) + 0.49 between the two data sets, with R2 = 0.47.
Total Mass Flux in the Northern Humboldt Current System: Rates and Contribution Sources from Central Peru (12° S)
Authors: Leigh Bobby , Aramayo Víctor , Mendoza Ursula , Velazco Federico , Kiko Rainer , Ayón Patricia , Fernández Ernesto , Graco Michelle
Published: September 2023

The total mass flux (TMF) of particulate organic matter (POM) is key for understanding the energetic transfer within the “biological pump” (i.e., involving the carbon cycle), reflecting a critical connection between the surface and the bottom. A fixed multi-sediment trap was installed at 30 m depth in Callao Bay, central Peru from March to December 2020. After recovery, samples were dried and weighed to calculate the TMF and pellet flux. The average TMF was 601.9 mg·m−2·day−1, with 70.2 and 860 mg·m−2·day−1 as the lowest and highest values during “normal conditions”. Zooplankton fecal pellets (ZFP) were found in ovoid (e.g., larvae) and cylindrical (e.g., adult copepods) shapes and their flux contribution to TMF was low, ranging from 0.17 to 85.59 mg·m−2·day−1. In contrast with ZFP, fish fecal pellets (FFP) were found in fragments with a cylindrical shape, and their contribution to the TMF was higher than ZFP, ranging from 1 to 92.56 mg·m−2·day−1. Mean sinking velocities were 4.63 ± 3.47 m·day−1 (ZFP) and 432.27 ± 294.26 m·day−1 (FFP). There is a considerable difference between the ZFP and FFP contributions to TMFs. We discuss the implications of these results regarding a still poorly understood process controlling the POM flux off the Peruvian coast.
Does Emerging Carbapenem Resistance in Acinetobacter baumannii Increase the Case Fatality Rate? Systematic Review and Meta-Analysis
Authors: Boral Jale , Pınarlık Fatihan , Ekinci Güz , Can Füsun , Ergönül Önder
Published: September 2023

Background: In the era of rising carbapenem resistance, we aimed to investigate the change in mortality rate and positivity of carbapenemase genes in Acinetobacter baumannii. Methods: Preferred Reporting Items for Systematic Review (PRISMA) guidelines were adopted in this systematic review. Our literature search included the Cochrane Library, Pubmed, Scopus, Web of Science, Medline, Tubitak TR Dizin, and Harman databases for studies dating back from 2003 to 2023 reporting bloodstream A. baumannii infections in Türkiye. A simple linear regression model was used to determine the association between resistance, mortality, and time. Results: A total of 1717 studies were identified through a literature search, and 21 articles were selected based on the availability of the data regarding mortality and resistance rate (four articles) or the molecular epidemiology of carbapenem-resistant A. baumannii (17 articles) in Türkiye. From 2007 to 2018, the carbapenem resistance rate increased (p = 0.025). The OXA-23 and OXA-58 positivities were inversely correlated (p = 0.025). Conclusions: Despite the emergence of carbapenem resistance, mortality did not increase in parallel, which may be due to improved medical advancements or the fitness cost of bacteria upon prolonged antimicrobial exposure. Therefore, we suggest further global research with the foresight to assess clonal relatedness that might affect the carbapenem resistance rate.
Predictors of Unmet Healthcare Needs during Economic and Health Crisis in Greece
Authors: Pierrakos George , Goula Aspasia , Latsou Dimitra
Published: September 2023

(1) Background: The aim of this study was to identify predictors of the unmet healthcare needs during the financial and recent health crisis in Greece. (2) Methods: Time series analysis was performed for the years 2008 through 2022 using the Eurostat database. The dependent variable was the percentage of people who reported unmet need for medical care. Demographic, socioeconomic, and health data, as well as health expenditures, were used as independent variables. Correlation analysis and simple linear regression models were conducted to analyze the results. (3) Results: Unmet health needs in Greece increased from the start of the crisis until 2016, as a gradual de-escalation of the crisis was observed. However, in 2019 the country recorded the second highest level of unmet needs for medical care before the health crisis. Limitations in usual activities, reporting bad/very bad health status, being unemployed, and having low income increased the likelihood of unmet needs. Health expenditures (public or private) were also significant determinants of unmet healthcare needs. (4) Conclusions: The increased unmet health needs widen inequalities in health and healthcare access. Therefore, health policies should eliminate barriers which restrict the access to health and enhance healthcare services, developing conditions for citizens’ well-being.
Misjudgement of One’s Own Performance? Exploring Attention Deficit (Hyperactivity) Disorder (ADHD) and Individual Difference in Complex Music and Foreign Language Perception
Authors: Groß Christine , Bernhofs Valdis , Möhler Eva , Christiner Markus
Published: September 2023

In previous research, we detected that children and adolescents who were diagnosed with ADHD showed deficits in both complex auditory processing of musical stimuli and in musical performance when compared to controls. In this study, we were interested in whether we could detect similar or distinct findings when we use foreign speech perception tasks. Therefore, we recruited musically naïve participants (n = 25), music-educated participants (n = 25) and participants diagnosed with ADHD (n = 25) who were assessed for their short-term memory (STM) capacity and the ability to discriminate music and speech stimuli and we collected self-ratings of the participants’ music and language performances. As expected, we found that young adults with ADHD show deficits in the perception of complex music and difficult speech perception stimuli. We also found that STM capacity was not impaired in young adults with ADHD and may not persist into young adulthood. In addition, subjective self-estimation about the participants’ language and music performances revealed that the ADHD group overestimated their performance competence relatively compared to both control groups. As a result, the findings of our study suggest that individuals diagnosed with ADHD require a special training program that not only focuses on improving performance in perceptual skills of music and language but also requires metacognitive training to develop realistic self-assessment skills.
Healthcare Policies to Eliminate Neglected Tropical Diseases (NTDs) in India: A Roadmap
Authors: Chandra Ajay , Sreeganga S. D. , Rath Nibedita , Ramaprasad Arkalgud
Published: September 2023

The need for systemic healthcare policies to systematically eliminate NTDs globally and in India has been stressed for more than two decades. Yet, the present policies and the research on them do not meet the need. We present an ontological framework, a research roadmap, and a policy brief to address the gap. The ontology clearly, concisely, and comprehensively represents the combinations of diseases, the objectives regarding the diseases, the entities to address them, the outcomes sought, and the potential policy instruments to invoke. The paper explicates the state of the-policies and state of the research on policies to eliminate NTDs in India. It highlights the significant gaps in the diseases covered, balance in the objectives, comprehensiveness of policies, portfolio of outcomes, and involvement of entities. Last, it presents a set of systemic policies congruent with the ontology to systematically address the gaps. The recommendations are aligned with the present research, policies, practices, and recommendations in India and of the WHO, UN agencies, and other similar bodies. The approach can be generalized to provide roadmaps for other countries facing a similar challenge and for other diseases of similar complexity. The roadmaps, with continuous feedback and learning, can help navigate the challenge efficiently and effectively.
The Roles of Depression, Life Control and Affective Distress on Treatment Attendance and Perceived Disability in Chronic Back Pain Sufferers throughout the Duration of the Condition
Authors: Oraison Humberto M. , Loton Daniel , Kennedy Gerard A.
Published: September 2023

The aims of this study were to examine psychological factors that predict treatment seeking and disability over the total duration of experiencing back pain. A sample of 201 adults experiencing chronic back pain was recruited through health professionals and completed the Depression, Anxiety and Stress Scale (DASS), the Oswestry Back Pain Disability Questionnaire (ODQ), the McGill Pain Questionnaire (MPQ) and the life control and affective distress variables of the West Haven–Yale Multidimensional Pain Inventory (WHYMP), and participants disclosed the number of treatment sessions attended over the course of the illness. Depression, life control and affective distress were tested as indirect predictors of disability severity that were mediated by treatment attendance. Each unit increase in life control predicted attending nearly 30 more treatment sessions, each unit increase in affective distress predicted attending 16 fewer treatments and each unit increase in depression predicted 4 fewer treatments, together explaining 44% of variance in treatment seeking. The effects of life control and affective distress on disability were explained by treatment attendance, whereas depression retained a direct effect on disability. Treatment attendance had an effect on disability. The findings show that participants with lower life control and higher affective distress and depression had higher levels of pain and disability, in part due to due to their treatment-seeking behaviour.
Treating Older Children with Clubfoot: Results of a Cross-Sectional Survey of Expert Practitioners
Authors: Drury Grace , Nunn Timothy R. , Dandena Firaol , Smythe Tracey , Lavy Christopher B. D.
Published: September 2023

Treating clubfoot in walking-age children is debated, despite studies showing that using the Ponseti casting principles can correct the midfoot effectively. We aimed to explore techniques and approaches for the management of older children with clubfoot and identify consensus areas. A mixed-methods cross-sectional electronic survey on delayed-presenting clubfoot (DPC) was sent to 88 clubfoot practitioners (response rate 56.8%). We collected data on decision-making, casting, imaging, orthotics, surgery, recurrence, rehabilitation, multidisciplinary care, and contextual factors. The quantitative data were analysed using descriptive statistics. The qualitative data were analysed using conventional content analysis. Many respondents reported using the Pirani score and some used the PAVER score to aid deformity severity assessment and correctability. Respondents consistently applied the Ponseti casting principles with a stepwise approach. Respondents reported economic, social, and other contextual factors that influenced the timing of the treatment, the decision to treat a bilateral deformity simultaneously, and casting intervals. Differences were seen around orthotic usage and surgical approaches, such as the use of tibialis anterior tendon transfer following full correction. In summary, the survey identified consensus areas in the overall principles of management for older children with clubfoot and the implementation of the Ponseti principles. The results indicate these principles are well recognised as a multidisciplinary approach for older children with clubfoot and can be adapted well for different geographical and healthcare contexts.