bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi-Fold Enhancement of Tocopherol Yields Employing High CO2 Supplementation and Nitrate Limitation in Native Isolate Monoraphidium sp.
Authors: Singh Rabinder , Nesamma Asha Arumugam , Narula Alka , Jutur Pannaga Pavan
Published: April 2022

Tocopherols are the highly active form of the antioxidant molecules involved in scavenging of free radicals and protect the cell membranes from reactive oxygen species (ROS). In the present study, we focused on employing carbon supplementation with varying nitrate concentrations to enhance the total tocopherol yields in the native isolate Monoraphidium sp. CABeR41. The total tocopherol productivity of NRHC (Nitrate replete + 3% CO2) supplemented was (306.14 µg·L−1 d−1) which was nearly 2.5-fold higher compared to NRVLC (Nitrate replete + 0.03% CO2) (60.35 µg·L−1 d−1). The best tocopherol productivities were obtained in the NLHC (Nitrate limited + 3% CO2) supplemented cells (734.38 µg·L−1 d−1) accompanied by a significant increase in cell biomass (2.65-fold) and total lipids (6.25-fold). Further, global metabolomics using gas chromatography-mass spectrometry (GC-MS) was done in the defined conditions to elucidate the molecular mechanism during tocopherol accumulation. In the present study, the Monoraphidium sp. responded to nitrogen limitation by increase in nitrogen assimilation, with significant upregulation in gamma-Aminobutyric acid (GABA). Moreover, the tricarboxylic acid (TCA) cycle upregulation depicted increased availability of carbon skeletons and reducing power, which is leading to increased biomass yields along with the other biocommodities. In conclusion, our study depicts valorization of carbon dioxide as a cost-effective alternative for the enhancement of biomass along with tocopherols and other concomitant products like lipids and carotenoids in the indigenous strain Monoraphidium sp., as an industrial potential strain with relevance in nutraceuticals and pharmaceuticals.
Effect of Vitamin D Supplementation on the Fetal Growth Rate in Pregnancy Complicated by Fetal Growth Restriction
Authors: Jakubiec-Wisniewska Karolina , Huras Hubert , Kolak Magdalena
Published: April 2022

Background: Fetal growth restriction (FGR) increases the risk of intrauterine fetal death, infant death and complications in childhood, and diseases that appear in adulthood. Vitamin D may affect fetal vascular flow. The aim of the study was to check if the rate of fetal growth in pregnant women with FGR differs depending on whether the patient was supplemented with vitamin D in the recommended dose of 2000 IU, not supplemented at all, or supplemented with vitamin D in low doses. Methods: Patients were divided into two groups: suboptimal vitamin D dosage and an accurate dosage of 2000 IU. Fetal growth progress was observed for 14 days. Results: Fetal weight was higher at the beginning, after 1 and 2 weeks of observation in the optimal vit. D group compared with the suboptimal group. The analysis was adjusted to the mother’s age, gestational week, and the number of pregnancies. Conclusions: Greater fetal weight gain can be observed in women with FGR (fetal growth restriction) who intake vitamin D at the recommended dose of 2000 IU compared with women with FGR and with a vitamin D intake dosage lower than 500 IU.
Increased Production of Interleukin-10 and Tumor Necrosis Factor-Alpha in Stimulated Peripheral Blood Mononuclear Cells after Inhibition of S100A12
Authors: Wu Huang-Pin , Chu Chien-Ming , Liu Pi-Hua , Leu Shaw-Woei , Lin Shih-Wei , Hu Han-Chung , Kao Kuo-Chin , Li Li-Fu , Yu Chung-Chieh
Published: April 2022

Sepsis may induce immunosuppression and result in death. S100A12 can bind to the receptor for advanced glycation end-products (RAGE) and Toll-like receptor (TLR)4 following induction of various inflammatory responses. It is unclear whether S100A12 significantly influences the immune system, which may be associated with sepsis-related mortality. We measured plasma S100A12 levels and cytokine responses (mean ± standard error mean) of lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs) after S100A12 inhibition in healthy controls and patients with sepsis on days one and seven. Day one plasma soluble RAGE (sRAGE) and S100A12 levels in patients with sepsis were significantly higher than those in controls (2481.3 ± 295.0 vs. 1273.0 ± 108.2 pg/mL, p < 0.001; 530.3 ± 18.2 vs. 310.1 ± 28.1 pg/mL, p < 0.001, respectively). Day seven plasma S100A12 levels in non-survivors were significantly higher than those in survivors (593.1 ± 12.7 vs. 499.3 ± 23.8 pg/mL, p = 0.002, respectively). In survivors, plasma sRAGE levels were significantly decreased after 6 days (2297.3 ± 320.3 vs. 1530.1 ± 219.1 pg/mL, p = 0.009, respectively), but not in non-survivors. Inhibiting S100A12 increased the production of tumor necrosis factor (TNF)-α and interleukin (IL)-10 in stimulated PBMCs for both controls and patients. Therefore, S100A12 plays an important role in sepsis pathogenesis. S100A12 may competitively bind to TLR4 and RAGE, resulting in decreased IL-10 and TNF-α production.
Morphology and FTIR Characteristics of the Alluvial Diamond from the Yangtze Craton, China
Authors: Cao Chuqi , Yang Jingsui , Zeng Fengshan , Liu Fei , Yang Shengbiao , Wang Yun
Published: April 2022

A total of 48 natural alluvial diamonds from the Yangtze Craton, China, also called Hunan diamonds, were studied using morphology and IR spectroscopy. These diamond samples, collected downstream of the Yuan River, Hunan Province, with unknown host-rock source(s), were observed by scanning electron microscope (SEM) and Fourier-transform infrared spectroscopy (FTIR). Most Hunan diamonds are monocrystal forms of octahedra, tetrahexahedra (THH) and dodecahedra; octahedral–rhom-dodecahedral transitional behaviors and irregular forms are also visible. Trigons and tetragons, terraces and shield-shaped laminae are surface features that frequently indicate dissolution and reabsorption; green and brown spots, network patterns, and other mechanical abrasion marks are typical evidence of long-time deposition and transportation of Hunan diamonds. The main types of Hunan diamonds are type IaAB and type Ⅱa. Diamond samples have a wide range of total nitrogen content (Ntot) from 196–1094 ppm. Two populations are distinguished by two-peak distribution models of NA (A-center concentrations) and %B (proportion of aggregated nitrogen). Hunan diamonds are low in structure hydrogen (0.03–4.67 cm−1, mostly below 1 cm−1) and platelets (0.23–17 cm−1, mostly below 2 cm−1). Moreover, there is a significant positive correlation between the hydrogen correlation peak and Ntot, which is similar to Argyle diamonds. The temperature conditions of the diamond formation have been estimated at 1075–1180 °C, mainly conforming to the kimberlite diamond range. Besides, some samples with slightly higher temperatures are close to the ultramafic-related Juina diamonds. Therefore, the FTIR characteristics analysis and comparison indicate the multiple sources of Hunan diamonds.
A Preliminary Study on the Relationship between Serum Heparan Sulfate and Cancer-Related Cognitive Impairment: The Moderating Role of Oxidative Stress in Patients with Colorectal Cancer
Authors: Wang Danhui , Wang Teng , Zhu Min , Sun Jun , Zhou Zhou , Chen Jinghua , Teng Liping
Published: April 2022

Cancer-related cognitive impairment (CRCI) has been frequently reported in colorectal cancer survivors. Heparan sulfate (HS) was gradually considered to be related to cognitive disorders. The effect and potential mechanism of HS on CRCI in colorectal cancer patients were unexplored. In this study, all participants were divided into a cognitive impaired group and a cognitive normal group. The concentrations of oxidative stress factors and HS in serum were detected. Associations among HS, oxidative stress factors and CRCI were evaluated. Participants with cognitive impairment exhibited increased levels of HS, GSH, SOD and MDA, compared to the patients with normal cognitive performance. The independent significant association was found between HS and CRCI after controlling for various covariates. The higher concentrations of HS were related to the decreased cognitive performance among survivors who reported higher levels of GSH (β = 0.080, p = 0.002). Moreover, the nonlinear association between the level of HS and cognitive scores was confirmed using the restricted cubic splines (p < 0.001). These results indicated that the increased concentrations of circulating HS had a nonlinear negative connection with cognitive performance in colorectal cancer survivors, which was moderated by GSH. HS might be a new biomolecule for the identification and management of patients with CRCI.
A Dataset of Dropout Rates and Other School-Level Variables in Louisiana Public High Schools
Authors: Stein Michael , Leitner Michael , Trepanier Jill C. , Konsoer Kory
Published: April 2022

Students dropping out of high school is a nationwide problem in the United States, plaguing communities and often greatly reducing the prospects of a quality life for those students who do not complete their high school education. The state of Louisiana consistently has among the highest public high school dropout rates in the United States and, often, the highest. This massive dataset of school variables covering a duration of five academic years (2014–2015 to 2018–2019) was originally compiled with the intention of identifying the factors that correlate with high school dropouts in Louisiana public high schools, specifically. However, it can be useful to any researchers interested in analyzing school-level data concerning a wide range of variables beyond merely dropout rates. This dataset also contains socioeconomic demographics, financial variables, class size, and much more. The correlation analyses ultimately revealed many intriguing insights into the relationships between the tested variables and the dropout rates.
Brain Networks Involved in Depression in Patients with Frontotemporal Dementia and Parkinson’s Disease: An Exploratory Resting-State Functional Connectivity MRI Study
Authors: Alfano Vincenzo , Federico Giovanni , Mele Giulia , Garramone Federica , Esposito Marcello , Aiello Marco , Salvatore Marco , Cavaliere Carlo
Published: April 2022

Depression is characterized by feelings of sadness, loss, or anger that may interfere with everyday activities. Such a neuropsychiatric condition is commonly reported in multiple neurodegenerative disorders, which are quite different from each other. This study aimed at investigating the brain networks involved in depression in patients with frontotemporal dementia (FTD) and Parkinson’s disease (PD) as compared to healthy controls (HC). Fifty participants were included in the study: 17 depressed FTD/PD patients; 17 non-depressed FTD/PD patients; and 16 non-depressed HCs matched for age and gender. We used the Beck depression inventory (BDI-II) to measure depression in all groups. On the same day, 3T brain magnetic resonance with structural and resting-state functional sequences were acquired. Differences in resting-state functional connectivity (FC) between depressed and non-depressed patients in all the experimental groups were assessed by using seed-to-seed and network-to-network approaches. We found a significant seed-to-seed hyperconnectivity patterns between the left thalamus and the left posterior temporal fusiform cortex, which differentiated FTD/PD depressed patients from the HCs. Network-to-network analysis revealed a significant hyperconnectivity among the default-mode network (left lateral-parietal region), the medial prefrontal cortex and the left lateral prefrontal cortex (i.e., part of the central executive network). We investigated whether such FC patterns could be related to the underlying neurodegenerative disorder by replicating the analyses with two independent samples (i.e., non-depressed PD and non-depressed FTD patients) and adding clinical parameters as covariates. We found no FC differences in these groups, thus suggesting how the FC pattern we found may signal a common depression-related neural pathway implicated in both the neurocognitive disorders.
Histological Diagnostic Yield and Clinical Significance of the First Biopsy in Device-Assisted Enteroscopy in Patients with Small Bowel Diseases: A KASID Multicenter Study
Authors: Goong Hyeon Jeong , Kim Tae Joon , Nam Kwangwoo , Park Jihye , Kim Jin-Oh , Kim Hyun Gun , Ko Bong Min , Jeon Seong Ran ,   Small Intestine Research Group of the Korean Association for the Study of Intestinal Diseases (KASID)
Published: April 2022

Device-assisted enteroscopy (DAE) enables the direct visualization of small bowel lesions with histological diagnosis; however, few studies have described the diagnostic performance of enteroscopic biopsy. We investigated the diagnostic performance of enteroscopic biopsy. We used a nationwide multicenter enteroscopy database to identify patients who underwent DAE with biopsy for small bowel diseases. The patients were classified into the tumor and non-tumor groups according to the final diagnosis. They were also divided into diagnostic and non-diagnostic groups based on the enteroscopic biopsy results. The clinical significance of the first biopsy and histological diagnostic yield of DAE were analyzed. Among the 112 procedures investigated, 32 (28.9%) were diagnosed with tumors, and 80 (71.7%) were diagnosed with non-tumor diseases. The overall histological diagnostic yield of DAE was 43.7%. The histological diagnostic yield was significantly higher in the tumor than in the non-tumor group (81.2% vs. 28.8%, p < 0.001). The mean number of biopsies was significantly higher in the diagnostic than in the non-diagnostic group (5.6 ± 3.3 vs. 3.7 ± 2.1, p = 0.001). In the diagnostic group, 87.7% of the cases were histologically confirmed at the first biopsy. Therefore, the first biopsy should be performed carefully.
Validation of the 30-Year Framingham Risk Score in a German Population-Based Cohort
Authors: Rospleszcz Susanne , Starnecker Fabian , Linkohr Birgit , von Scheidt Moritz , Gieger Christian , Schunkert Heribert , Peters Annette
Published: April 2022

The Framingham Risk Score to predict 30-year risk (FRS30y) of cardiovascular disease (CVD) constitutes an important tool for long-term risk prediction. However, due to its complex statistical properties and the paucity of large population-based cohorts with appropriate data, validation of the FRS30y is lacking. A population-based cohort from Southern Germany (N = 3110, 1516 (48.7%) women) was followed up for a median time of 29.5 [18.7, 31.2] years. Discrimination and calibration were assessed for the original, recalibrated and refitted FRS30y version. During follow up, 620 incident CVD events (214 in women) occurred. The FRS30y showed adequate discrimination (original and recalibrated version: Area under the curve (AUC): 78.4 for women and 74.9 for men) but overestimated actual CVD risk (original version: discordance 45.4% for women and 37.3% for men, recalibrated version: 37.6% and 28.6%, respectively). Refitting showed substantial improvement in neither discrimination nor calibration. The performance of FRS30y is adequate for long-term CVD risk prediction and could serve as an important tool in risk communication, especially for younger audiences.
Nucleic Acid Biomarkers in Waldenström Macroglobulinemia and IgM-MGUS: Current Insights and Clinical Relevance
Authors: Drandi Daniela , Decruyenaere Philippe , Ferrante Martina , Offner Fritz , Vandesompele Jo , Ferrero Simone
Published: April 2022

Waldenström Macroglobulinemia (WM) is an indolent lymphoplasmacytic lymphoma, characterized by the production of excess immunoglobulin M monoclonal protein. WM belongs to the spectrum of IgM gammopathies, ranging from asymptomatic IgM monoclonal gammopathy of undetermined significance (IgM-MGUS), through IgM-related disorders and asymptomatic WM to symptomatic WM. In recent years, its complex genomic and transcriptomic landscape has been extensively explored, hereby elucidating the biological mechanisms underlying disease onset, progression and therapy response. An increasing number of mutations, cytogenetic abnormalities, and molecular signatures have been described that have diagnostic, phenotype defining or prognostic implications. Moreover, cell-free nucleic acid biomarkers are increasingly being investigated, benefiting the patient in a minimally invasive way. This review aims to provide an extensive overview of molecular biomarkers in WM and IgM-MGUS, considering current shortcomings, as well as potential future applications in a precision medicine approach.
COVID-19 in Tunisia (North Africa): Seroprevalence of SARS-CoV-2 in the General Population of the Capital City Tunis
Authors: Cherif Ines , Kharroubi Ghassen , Chaabane Sana , Yazidi Rihab , Dellagi Mongi , Snoussi Mohamed Ali , Salem Sadok , Marzouki Soumaya , Kammoun Rebai Wafa , Rourou Samia , Dellagi Koussay , Barbouche Mohamed Ridha , Benabdessalem Chaouki , Ben Ahmed Melika , Bettaieb Jihene
Published: April 2022

Seroprevalence studies are essential to get an accurate estimate of the actual SARS-CoV-2 diffusion within populations. We report on the findings of the first serosurvey conducted in Tunis prior to the implementation of mass vaccination and analyzed factors associated with seropositivity. A household cross sectional survey was conducted (March–April 2021) in Tunis, spanning the end of the second wave and the beginning of the third wave of COVID-19. SARS-CoV-2 specific immunoglobulin G (IgG) antibodies to the spike (S-RBD) or the nucleocapsid (N) proteins were detected by in-house ELISA tests. The survey included 1676 individuals from 431 households. The mean age and sex ratio were 43.3 ± 20.9 years and 0.6, respectively. The weighted seroprevalence of anti-N and/or anti-S-RBD IgG antibodies was equal to 38.0% (34.6–41.5). In multivariate analysis, age under 10, no tobacco use, previous diagnosis of COVID-19, a history of COVID-19 related symptoms and contact with a COVID-19 case within the household, were independently associated with higher SARS-CoV-2 seroprevalence. More than one third of people living in Tunis obtained antibodies to SARS-CoV-2. Further studies are needed to monitor changes in these figures as Tunisian population is confronted to the subsequent epidemic waves and to guide the vaccine strategy.
Influence of Mo on the Microstructure and Corrosion Behavior of Laser Cladding FeCoCrNi High-Entropy Alloy Coatings
Authors: Li Wenjuan , Guo Wenmin , Zhang Hongling , Xu Huanhuan , Chen Liang , Zeng Junshan , Liu Bin , Ding Zhibing
Published: April 2022

FeCoCrNi and FeCoNiCrMo0.2 high-entropy alloy powders were prepared by gas atomization. Two kinds of coatings were prepared on the surface of 304 stainless steel by laser cladding technology. The effect of Mo element on the microstructure of laser cladding FeCoCrNi coating and its corrosion behavior in 3.5 wt.% NaCl solution was investigated. Both FeCoCrNi and FeCoCrNiMo0.2 powders exhibit a single-phase FCC structure. Due to the remelting and multiple heat treatments during the preparation of the laser cladding coating, a small amount of σ and μ phases appeared in the FeCoCrNiMo0.2 coating. The microstructures of the two coatings from the bonding area to the top layer are planar, columnar and equiaxed grains, respectively. The addition of the Mo element causes the dendrite size in the middle region of the FeCoCrNiMo0.2 coating increases significantly and exhibits obvious orientation characteristics. FeCoCrNiMo0.2 coating has high corrosion potential (−0.01 VSHE) and low current density (0.94 × 10−7 A/cm2) in 3.5 wt.% NaCl solution, showing excellent corrosion resistance. The passivation film formed on corroded the FeCoCrNiMo0.2 coating contains high content of oxides of Cr and Mo. The addition of the Mo element enhances the compactness and pitting resistance of the passivation film.
On the Age of Information in a Two-User Multiple Access Setup
Authors: Salimnejad Mehrdad , Pappas Nikolaos
Published: April 2022

This work considers a two-user multiple access channel in which both users have Age of Information (AoI)-oriented traffic with different characteristics. More specifically, the first user has external traffic and cannot control the generation of status updates, and the second user monitors a sensor and transmits status updates to the receiver according to a generate-at-will policy. The receiver is equipped with multiple antennas and the transmitters have single antennas; the channels are subject to Rayleigh fading and path loss. We analyze the average AoI of the first user for a discrete-time first-come-first-served (FCFS) queue, last-come-first-served (LCFS) queue, and queue with packet replacement. We derive the AoI distribution and the average AoI of the second user for a threshold policy. Then, we formulate an optimization problem to minimize the average AoI of the first user for the FCFS and LCFS with preemption queue discipline to maintain the average AoI of the second user below a given level. The constraints of the optimization problem are shown to be convex. It is also shown that the objective function of the problem for the first-come-first-served queue policy is non-convex, and a suboptimal technique is introduced to effectively solve the problem using the algorithms developed for solving a convex optimization problem. Numerical results illustrate the performance of the considered optimization algorithm versus the different parameters of the system. Finally, we discuss how the analytical results of this work can be extended to capture larger setups with more than two users.
Effects of Japanese Special Moras Education Using Evernote
Authors: Lee Hyun-jin , Kang Min-seok , Kwon Hee-ju
Published: April 2022

In this study, we designed a class model using the Evernote application for the pronunciation learning of special moras, and applied it to a class to verify the learner’s recognition of special moras and the effectiveness of pronunciation duration. This study consisted of 30 students who took an intermediate Japanese language class, which started in the first semester of 2019, and Japanese literature majors who had not yet been in Japan for more than 6 months. We conducted special mora pre- and post-tests and surveyed them. Positive results were obtained based on the research question of whether the application affects the self-awareness of special moras, which represented a significant academic achievement in terms of pronunciation duration. In addition, it was observed that learning using Evernote enabled a significant change in lecture satisfaction through one-to-one feedback work with learners. Although the research results were limited by the small size of the group, it was possible to suggest a method of special moras learning using Evernote, and it is believed that it will help in-class learning in the future.
Embedding a Coaching Culture into Programmatic Assessment
Authors: King Svetlana Michelle , Schuwirth Lambert W. T. , Jordaan Johanna H.
Published: April 2022

Educational change in higher education is challenging and complex, requiring engagement with a multitude of perspectives and contextual factors. In this paper, we present a case study based on our experiences of enacting a fundamental educational change in a medical program; namely, the steps taken in the transition to programmatic assessment. Specifically, we reflect on the successes and failures in embedding a coaching culture into programmatic assessment. To do this, we refer to the principles of programmatic assessment as they apply to this case and conclude with some key lessons that we have learnt from engaging in this change process. Fostering a culture of programmatic assessment that supports learners to thrive through coaching has required compromise and adaptability, particularly in light of the changes to teaching and learning necessitated by the global pandemic. We continue to inculcate this culture and enact the principles of programmatic assessment with a focus on continuous quality improvement.
Multi-Task Learning Using Gradient Balance and Clipping with an Application in Joint Disparity Estimation and Semantic Segmentation
Authors: Guo Yiyou , Wei Chao
Published: April 2022

In this paper, we propose a novel multi-task learning (MTL) strategy from the gradient optimization view which enables automatically learning the optimal gradient from different tasks. In contrast with current multi-task learning methods which rely on careful network architecture adjustment or elaborate loss functions optimization, the proposed gradient-based MTL is simple and flexible. Specifically, we introduce a multi-task stochastic gradient descent optimization (MTSGD) to learn task-specific and shared representation in the deep neural network. In MTSGD, we decompose the total gradient into multiple task-specific sub-gradients and find the optimal sub-gradient via gradient balance and clipping operations. In this way, the learned network can satisfy the performance of specific task optimization while maintaining the shared representation. We take the joint learning of semantic segmentation and disparity estimation tasks as the exemplar to verify the effectiveness of the proposed method. Extensive experimental results on a large-scale dataset show that our proposed algorithm is superior to the baseline methods by a large margin. Meanwhile, we perform a series of ablation studies to have a deep analysis of gradient descent for MTL.
Reduction of Complexity Design of SAC OCDMA Systems by Utilizing Diagonal Permutation Shift (DPS) Codes with Single Photodiode (SPD) Detection Technique
Authors: Ahmed Hassan Yousif , Zeghid Medien , Bouallegue Belgacem , Chehri Abdellah , Abd El-Mottaleb Somia A.
Published: April 2022

In this paper, a diagonal permutation code is presented for spectral amplitude coding optical code division multiple access (SAC-OCDMA) employing a single photodiode (SPD) detection technique. It is characterized by practical code length and ideal in-phase cross correlation (CC) that results in multiple access interference (MAI) suppression. A diagonal permutation shift (DPS) code can be constructed using both prime codes and some matrix operations. In addition, it can be easily implemented as it exists for prime numbers P, which limits the addressing probability of codes to P2. Fiber Bragg gratings (FBGs) are used for code encoding and decoding. Simulation analysis that calibrates with BER, Q-factor, and eye diagram proves that DPS code using SPD technique is able to maintain error free transmission compared to the complementary detection scheme (CDS) technique. It is reported that a reduction of fiber Bragg grating (FBG) sets by 41.6% was achieved for SPD over CDS techniques.
Priority-Aware Conflict Resolution for U-Space
Authors: Jover Jesús , Bermúdez Aurelio , Casado Rafael
Published: April 2022

In the context of the future urban mobility airspaces, U-space lays the foundation for unmanned aircrafts to be integrated with conventionally manned traffic to offer a multitude of services to citizens and businesses, such as urban public transport, goods movement, parcel delivery, etc. Given these extensive possibilities, it is estimated that thousands of aircrafts (or even more) from different owners will share common airspace volumes, and the probability that all of them will travel without colliding is extremely low if no means are put in place to prevent it. This paper aims to introduce the reader to the conflict management policy proposed in U-space and proposes a new version of the PCAN (Prediction-based Conflict-free Adaptive Navigation) algorithm to adapt to this policy. In particular, the new implementation of PCAN takes into account a more than likely classification of flights according to their priority. The evaluation of this priority-aware algorithm shows that it is still possible to avoid any conflict between the set of aircraft in flight, with an insignificant detriment to higher priority flights, while maintaining minimal detriment on average.
A Multi-Scale Fractal Approach for Coal Permeability Estimation via MIP and NMR Methods
Authors: Ren Weiguang , Zhou Hongwei , Zhong Jiangcheng , Xue Dongjie , Wang Chaosheng , Liu Zelin
Published: April 2022

Permeability in porous media has an important role in many engineering applications, which depends mainly on the pore size, distribution, and connectivity of porous media. As the pore structure distribution of coal has a multi-scale fractal dimension characteristic, this study aimed to propose a multi-scale fractal dimension characteristics units model (MFU) to describe the pore structure distribution by analyzing the multi-scale fractal dimension characteristics of coal pore media. Then, a multi-scale fractal permeability model was established based on MFU. The pore structure distribution was obtained by mercury injection porosimetry (MIP) and nuclear magnetic resonance (NMR) experiments. Based on MIP and NMR experimental data, the permeability contribution of different pore diameters were calculated. The results show that the permeability contribution of the micropore was minimal and can be ignored. The permeability contribution of mesopores was about 1–5%, and the permeability contribution of macropores was about 95–99%, which plays a decisive role in the seepage process. The calculated results, based on multi-scale fractal permeability model and the experimental permeability data, are in the same order of magnitude. The permeability prediction based on proposed model is better than classical single fractal permeability model.
Effect of Volatile Fatty Acids Accumulation on Biogas Production by Sludge-Feeding Thermophilic Anaerobic Digester and Predicting Process Parameters
Authors: Al-Sulaimi Intisar Nasser , Nayak Jagdeep Kumar , Alhimali Halima , Sana Ahmed , Al-Mamun Abdullah
Published: April 2022

Sewage sludge represents an important resource for reuse in the wastewater treatment field. Hence, thermophilic anaerobic digestion (TAD) could be an alternative technique to recover renewable resources from sludge. In the TAD biodegradation process, volatile fatty acids (VFAs) are the intermediate products of methanogenesis. However, the higher formation and accumulation of VFAs leads to microbial stress, resulting in acidification and failure of the digester. Therefore, several batch TADs have been investigated to evaluate the VFAs production from sludge and their impact on biogas generation and biodegradation efficiency. Three types of sewage sludges, e.g., primary sludge (PS), secondary sludge (SS), and mixed sludge (MS) were used as substrates to estimate the accumulation of VFAs and yield of methane gas. The system showed the maximum total VFAs accumulation from both PS and MS as 824.68 ± 0.5 mg/L and 236.67 ± 0.5 mg/L, respectively. The dominant VFA accumulation was identified as acetic acid, the main intermediate by-product of methane production. The produced biogas from PS and MS contained 66.75 ± 0.5% and 52.29 ± 0.5% methane, respectively. The high content of methane with PS-feeding digesters was due to the higher accumulation of VFAs (i.e., 824.68 ± 0.5 mg/L) in the TAD. The study also predicted the design parameters of TAD process by fitting the lab-scale experimental data with the well-known first-order kinetic and logistic models. Such predicted design parameters are significantly important before the large-scale application of the TAD process.
The Technological Perspectives of Kombucha and Its Implications for Production
Authors: Oliveira Ícaro Alves Cavalcante Leite de , Rolim Victória Ananias de Oliveira , Gaspar Roberta Paulino Lopes , Rossini Daniel Quarentei , de Souza Rayane , Bogsan Cristina Stewart Bittencourt
Published: April 2022

Fermentation is one of the oldest biotechnological tools employed by mankind. Fermenting food gives them better sensory and nutritional qualities, the latter including vitamins, phenolic compounds, antioxidants, and antimicrobials. Kombucha is the result of the fermentation of a sweetened Camellia sinensis infusion by the action of a symbiotic community of yeasts and bacteria organized in a cellulosic biofilm called SCOBY and has gained great prominence among fermented foods and beverages, with a considerable increase in its popularity in the last decade, both among consumers and within the scientific community. This is explained by the particular functional and microbial characteristics of this beverage, such as its antioxidant and antimicrobial potential, long-term stable microbial communities, its suitability for fermentation under different conditions of time and temperature, and amenability to other carbon sources besides sucrose. Thus, this review aims to present and discuss the functional, microbial, and physicochemical aspects of kombucha fermentation, covering the many challenges that arise in its production, in domestic, commercial, and legislation contexts, and the next steps that need to be taken in order to understand this drink and its complex fermentation process.
Two Methods to Improve the Efficiency of Supersonic Flow Simulation on Unstructured Grids
Authors: Kozelkov Andrei S. , Struchkov Andrei V. , Strelets Dmitry Y.
Published: April 2022

The paper presents two methods to improve the efficiency of supersonic flow simulation using arbitrarily shaped unstructured grids. The first method promotes increasing the numerical solution convergence rate and is based on the geometric multigrid method for initialization of the flow field. The method is used to obtain the initial field of distributed physical quantity values, which maximally corresponds to the converged solution. For this purpose, the problem simulation is performed on a series of coarse grids beginning from the coarsest one in this series. Upon completion of simulations, the solution obtained is interpolated to a finer grid and used for initialization of simulations on this grid. The second method allows increasing the numerical solution accuracy and is based on statically adapting the computational grid to the flow specifics. The static adaptation algorithm provides automatic refinement of the computational grid in the region of specific features of flow, such as shock waves typical for supersonic flows. This algorithm provides a better description of the shock-wave front owing to the local grid refinement, with the local refinement region being automatically selected. Results of using these methods are demonstrated for the two supersonic aerodynamics problems: the simulation of the bow shock strength at a given distance under axially symmetric body Seeb-ALR and a mock-up aircraft Lockheed Martin 1021. It is shown that in both cases, the numerical solution convergence rate is increased owing to the use of the geometric multigrid method for initialization and a higher quality and a higher accuracy of solution is gained owing to the local grid refinement (using static adaptation means) near the shock-wave front.
Disentangling Drivers of Food Waste in Households: Evidence from Nigeria
Authors: Sunday Calvin Oluwafemi , Sowunmi Fatai Abiola , Obayelu Oluwakemi Adeola , Awoyemi Abiodun Emmanuel , Omotayo Abiodun Olusola , Ogunniyi Adebayo Isaiah
Published: April 2022

Food waste is a burden on society in terms of the money wasted. There is limited information on the determinants of food waste and the amount lost to food waste by households as most previous studies were on post-harvest losses. Hence, determinants of food waste among households in Kogi West Senatorial District, Kogi State Nigeria were investigated. A three-stage sampling technique was used to select the respondents, while a structured questionnaire was used for data collection. Data were analyzed using Tobit regression and an equality test. The study revealed that food waste was higher in male headed households. The average monthly food waste proportion among urban households was significantly higher than that of rural households. The estimated amounts lost to food waste per month were ₦2103 and ₦5530 for the rural and urban households, respectively. These represented 7.2% and 13.1% of the total expenditure on food per month for rural and urban households, respectively. Among rural households, leftovers of food and lack of proper storage were the main reasons for food waste, while leftovers of food and preparation of food more than needed were the reasons for food waste among urban households. The sex of respondents, work experience, and monthly income influenced the proportion of food waste among rural households, while the dependency ratio, monthly income, and monthly food expenditure were the determinants of proportion of food waste among the urban households. Non-Governmental Organization efforts through sensitization campaigns focused on the need to reduce food waste, especially among urban households, would help to reduce the financial burden of food waste on households.
Nutritional and Antioxidant Properties of Moringa oleifera Leaves in Functional Foods
Authors: Peñalver Rocío , Martínez-Zamora Lorena , Lorenzo José Manuel , Ros Gaspar , Nieto Gema
Published: April 2022

Moringa oleifera is a tree cultivated originally in northern India, whose ancient use as a medicine has demonstrated its antioxidant and anti-inflammatory properties. Due to its richness in minerals and macronutrients, the antioxidant capacity and the mineral bioaccesibility were assessed. In addition, the chemical composition, amino acid, fatty acid, and mineral content were also evaluated. The performed analysis reported a high content of proteins and low content of lipids in the chemical composition. Regarding the mineral content, Ca and Fe presented high bioaccessibility; K, S, Ca, and Fe being the most concentrated elements. The obtained values using FRAP, ABTS, and ORAC methods showed high antioxidant capacity, directly related to the increased content of phenolic compounds. In view of the results, Moringa oleifera can be incorporated into the diet as a functional ingredient or as a fortifier of any kind of food. The important source of minerals, phenolics, proteins, unsaturated fats, and folates make it an excellent extract with beneficial properties.
Interlaboratory Validation of a DNA Metabarcoding Assay for Mammalian and Poultry Species to Detect Food Adulteration
Authors: Dobrovolny Stefanie , Uhlig Steffen , Frost Kirstin , Schlierf Anja , Nichani Kapil , Simon Kirsten , Cichna-Markl Margit , Hochegger Rupert
Published: April 2022

Meat species authentication in food is most commonly based on the detection of genetic variations. Official food control laboratories frequently apply single and multiplex real-time polymerase chain reaction (PCR) assays and/or DNA arrays. However, in the near future, DNA metabarcoding, the generation of PCR products for DNA barcodes, followed by massively parallel sequencing by next generation sequencing (NGS) technologies, could be an attractive alternative. DNA metabarcoding is superior to well-established methodologies since it allows simultaneous identification of a wide variety of species not only in individual foodstuffs but even in complex mixtures. We have recently published a DNA metabarcoding assay for the identification and differentiation of 15 mammalian species and six poultry species. With the aim to harmonize analytical methods for food authentication across EU Member States, the DNA metabarcoding assay has been tested in an interlaboratory ring trial including 15 laboratories. Each laboratory analyzed 16 anonymously labelled samples (eight samples, two subsamples each), comprising six DNA extract mixtures, one DNA extract from a model sausage, and one DNA extract from maize (negative control). Evaluation of data on repeatability, reproducibility, robustness, and measurement uncertainty indicated that the DNA metabarcoding method is applicable for meat species authentication in routine analysis.
Comparison between Conventional and Non-Conventional Computer Methods to Define Antiknock Properties of Fuel Mixtures
Authors: Pulga Leonardo , Lacrimini Diego , Forte Claudio , Mariani Valerio , Falfari Stefania , Bianchi Gian Marco
Published: April 2022

Research Octane Number (RON) is one of the primary indicators for the determination of the resistance of gasoline fuels to autoignition. This parameter is usually determined with a test procedure involving a standardized engine that requires expensive hardware and time-consuming tests. In this work, a set of different methods with which to determine the RON of gasoline fuel surrogates is presented, considering only computer simulations, which allows to reduce both cost and time for the evaluation. A palette of 11 chemical species has been chosen as the basis for the surrogates’ database, which will be investigated in the work, allowing the representation of the complex chemical formulation of fuels in an easier way. A simplified zero-dimensional engine model of the standard variable compression ratio is used to provide pressure and temperature, then employed to calculate RON. This is done first by means of existing methods, and then by introducing new processes concerning a simplified chemical reactor built on kinetic schemes. Finally, these different methodologies are tested against a molar weighted sum of RONs of each chemical specie, allowing to have a criterion for comparison and evaluating their real prediction capabilities.
Recent Advances in Hydrogel-Based Sensors Responding to Ionizing Radiation
Authors: Zhang Ping , Jiang Li , Chen Hong , Hu Liang
Published: April 2022

Ionizing radiation and its applications are widely spread throughout life. Similar to many other things, both the positive and negative aspects of ionizing radiation should always be kept in mind. For example, a proper radiation dose can be delivered to tumor tissue to kill malignant cells in radiotherapy. On the other hand, exceeding this dose can damage the normal tissues of a human organism. Therefore, the application of sensors for measuring ionizing radiation doses is of utmost importance in many fields, especially in cancer therapy. Traditional dosimeters, such as ionization chambers, silicon diodes and thermoluminescence dosimeters, are widely used. However, they have limitations in certain aspects. Hydrogel-based sensors (or dosimeters) for measuring ionizing radiation doses attract extensive attention for decades due to their equivalence to living tissue and biocompatibility. In this review, we catalog hydrogel-based dosimeters such as polymer, Fricke, radio-chromic, radio-fluorescence and NPs-embedded dosimeters. Most of them demonstrate desirable linear response and sensitivity regardless of energy and dose rate of ionizing radiation. We aim to review these dosimeters and their potential applications in radiotherapy as well as to stimulate a joint work of the experts from different fields such as materials science, chemistry, cancer therapy, radiobiology and nuclear science.
COVID-19 and Molecular Genetics
Authors: Novelli Giuseppe , Biancolella Michela
Published: April 2022

Since early December 2019, the COVID-19 pandemic has impacted global society: over 400 million people have been infected with SARS-CoV-2, and there have been nearly 6 million deaths worldwide (1 [...]
Translation, Adaptation, and Psychometric Validation of the Spanish Version of the Attitudes towards Research and Development within Nursing Questionnaire
Authors: Gros Navés Silvia , Canet-Vélez Olga , Contreras-Higuera Williams , Garcia-Expósito Judith , Torralbas-Ortega Jordi , Roca Judith
Published: April 2022

The promotion of research competence is essential for the development of the nursing profession and discipline. The aim of this study was to translate into Spanish, adapt, and validate an instrument measuring nurses’ attitudes towards nursing research and development. A quantitative, cross-sectional, analytical design was used for the cross-cultural adaptation and cultural validation of the instrument. A total of 367 participants were selected using intentional sampling. A process of translation, back-translation, expert consultation, and pilot testing was followed. Subsequently, reliability and statistical validity were assessed, a new factor structure was proposed, and means were compared to assess the power to discriminate between factors by groups of participants. The results showed internal consistency tests with a Cronbach’s alpha of 0.913. Confirmatory factor analysis of the comparative fit index (CFI = 0.549) and Tucker–Lewis index (TLI = 0.491) indicate that the factors did not match the original clustering model. The new factor structure consisted of seven factors. Between-group comparisons revealed statistically significant differences. In conclusion, the instrument exhibits high levels of statistical reliability and validity compared to the original instrument. The new factorial proposal is consistent, but further research is needed to verify its replicability in other contexts.
Rostering in Air Traffic Control: A Narrative Review
Authors: Terenzi Michela , Ricciardi Orlando , Di Nocera Francesco
Published: April 2022

Most Air Traffic Controllers (ATCOs) must cover uninterrupted work shifts for 24 h a day, seven days a week. The proper planning of a shift schedule requires consideration of at least three elements: the specific characteristics of the controller task, the physiological needs of the operator, and the definition of rest periods within rostering. We reviewed the literature for providing comprehensive guidance on the main requirements for the construction of a shift schedule for ATCOs. Our considerations are organized according to a rationale reflecting the most important criteria for the construction of the schedule: namely, the organization of rest periods conceptualized as intervals between cycles of shifts, intervals between individual shifts, and breaks within the shift. The suggested parameters could be used to construct shift schedules within a variation margin that depends on individual contexts of application.
Effect of Cigarette and E-Cigarette Smoke Condensates on Candida albicans Biofilm Formation and Gene Expression
Authors: Haghighi Farnoosh , Andriasian Leah , Tran Nini Chaichanasakul , Lux Renate
Published: April 2022

Smoking triggers environmental changes in the oral cavity and increases the risk of mucosal infections caused by Candida albicans such as oral candidiasis. While cigarette smoke has a significant impact on C. albicans, how e-cigarettes affect this oral pathogen is less clear. Here, we investigated the effect of cigarette and e-cigarette smoke condensates (CSC and ECSC) on C. albicans growth, biofilm formation, and gene expression. Whereas pure nicotine (N) at the minimum inhibitory concentration (MIC, 4 mg/mL) prevented C. albicans growth, enhanced biofilm formation was observed at 0.1 mg/mL. In contrast, at this nicotine sub-MIC (0.1 mg/mL) concentration, CSC and ECSC had no significant effect on C. albicans biofilm formation. Additionally, N, CSC, and ECSC increased the expression of HWP1 and SAP2 genes. The ECSC group exhibited elevated expression levels of the EAP1 and ALS3 genes, compared to the nicotine-free ECSC (−) control. Moreover, our in vitro study illustrated that the antifungal drugs, fluconazole and amphotericin B, alleviated the effect of nicotine on C. albicans gene expression. Overall, the results of the study indicated nicotine from different sources may affect the pathogenic characteristics of C. albicans, including hyphal growth, biofilm formation, and particularly the expression of virulence-related genes.