bluuebunny/crossref_metadata_2025 huggingface dataset:
Factors Determining Genotypic Variation in the Speed of Rice Germination
Authors: Chao Sinh , Mitchell Jaquie , Fukai Shu
Published: August 2021

Rapid germination is important for both direct seeded rice in the field and for the production of germinated brown rice for healthy food. This study aims to evaluate genotypic differences in germination speed and identify characteristics that determine germination speed. Seven experiments were conducted to determine (i) the impact of dehulling on water absorption and germination, (ii) variety consistency in germination speed across crops grown in three years, and (iii) the effect of grain size. Germination speed in both paddy rice and dehulled brown rice was significantly correlated with grain moisture content at early stages of soaking, however significant interaction of genotype and grain type (paddy and brown rice) existed and varieties differed in their response to dehulling. Germination speed of grain from crops exposed to water deficit in the field was slightly slower than those with higher water supply. Sherpa/IRAT109 genotypes with smaller grain size tended to germinate faster than larger grain, however no significant effect of grain size existed among diversity set varieties. It was concluded that genotype ranking in germination speed was consistent across years and water availability conditions, and that barriers to water absorption in hull and pericarp were important determinants of germination speed. The existence of genotypic variation in germination speed has management implications for both field crop establishment and paddy germination in food processing.
Pharmaceutical Approaches on Antimicrobial Resistance: Prospects and Challenges
Authors: Nainu Firzan , Permana Andi Dian , Djide Nana Juniarti Natsir , Anjani Qonita Kurnia , Utami Rifka Nurul , Rumata Nur Rahma , Zhang Jianye , Emran Talha Bin , Simal-Gandara Jesus
Published: August 2021

The rapid increase in pathogenic microorganisms with antimicrobial resistant profiles has become a significant public health problem globally. The management of this issue using conventional antimicrobial preparations frequently results in an increase in pathogen resistance and a shortage of effective antimicrobials for future use against the same pathogens. In this review, we discuss the emergence of AMR and argue for the importance of addressing this issue by discovering novel synthetic or naturally occurring antibacterial compounds and providing insights into the application of various drug delivery approaches, delivered through numerous routes, in comparison with conventional delivery systems. In addition, we discuss the effectiveness of these delivery systems in different types of infectious diseases associated with antimicrobial resistance. Finally, future considerations in the development of highly effective antimicrobial delivery systems to combat antimicrobial resistance are presented.
Teicoplanin Suppresses Vegetative Clostridioides difficile and Spore Outgrowth
Authors: Ojha Suvash Chandra , Phanchana Matthew , Harnvoravongchai Phurt , Chankhamhaengdecha Surang , Singhakaew Sombat , Ounjai Puey , Janvilisri Tavan
Published: August 2021

In recent decades, the incidence of Clostridioides difficile infection (CDI) has remained high in both community and health-care settings. With the increasing rate of treatment failures and its ability to form spores, an alternative treatment for CDI has become a global priority. We used the microdilution assay to determine minimal inhibitory concentrations (MICs) of vancomycin and teicoplanin against 30 distinct C. difficile strains isolated from various host origins. We also examined the effect of drugs on spore germination and outgrowth by following the development of OD600. Finally, we confirmed the spore germination and cell stages by microscopy. We showed that teicoplanin exhibited lower MICs compared to vancomycin in all tested isolates. MICs of teicoplanin ranged from 0.03–0.25 µg/mL, while vancomycin ranged from 0.5–4 µg/mL. Exposure of C. difficile spores to broth supplemented with various concentrations of antimicrobial agents did not affect the initiation of germination, but the outgrowth to vegetative cells was inhibited by all test compounds. This finding was concordant with aberrant vegetative cells after antibiotic treatment observed by light microscopy. This work highlights the efficiency of teicoplanin for treatment of C. difficile through prevention of vegetative cell outgrowth.
Oleoylethanolamide Reduces Hepatic Oxidative Stress and Endoplasmic Reticulum Stress in High-Fat Diet-Fed Rats
Authors: Giudetti Anna Maria , Vergara Daniele , Longo Serena , Friuli Marzia , Eramo Barbara , Tacconi Stefano , Fidaleo Marco , Dini Luciana , Romano Adele , Gaetani Silvana
Published: August 2021

Long-term high-fat diet (HFD) consumption can cause weight gain and obesity, two conditions often associated with hepatic non-alcoholic fatty liver and oxidative stress. Oleoylethanolamide (OEA), a lipid compound produced by the intestine from oleic acid, has been associated with different beneficial effects in diet-induced obesity and hepatic steatosis. However, the role of OEA on hepatic oxidative stress has not been fully elucidated. In this study, we used a model of diet-induced obesity to study the possible antioxidant effect of OEA in the liver. In this model rats with free access to an HFD for 77 days developed obesity, steatosis, and hepatic oxidative stress, as compared to rats consuming a low-fat diet for the same period. Several parameters associated with oxidative stress were then measured after two weeks of OEA administration to diet-induced obese rats. We showed that OEA reduced, compared to HFD-fed rats, obesity, steatosis, and the plasma level of triacylglycerols and transaminases. Moreover, OEA decreased the amount of malondialdehyde and carbonylated proteins and restored the activity of antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase, which decreased in the liver of HFD-fed rats. OEA had also an improving effect on parameters linked to endoplasmic reticulum stress, thus demonstrating a role in the homeostatic control of protein folding. Finally, we reported that OEA differently regulated the expression of two transcription factors involved in the control of lipid metabolism and antioxidant genes, namely nuclear factor erythroid-derived 2-related factor 1 (Nrf1) and Nrf2, thus suggesting, for the first time, new targets of the protective effect of OEA in the liver.
Morphological and Molecular Alterations Induced by Lead in Embryos and Larvae of Danio rerio
Authors: Curcio Vittoria , Macirella Rachele , Sesti Settimio , Pellegrino Daniela , Ahmed Abdalmoiz I. M. , Brunelli Elvira
Published: August 2021

Lead (Pb) is one of the most toxic and persistent elements and may adversely affect both humans and wildlife. Given the risks posed to humans, lead is listed among priority substances of public health importance worldwide. In fish, available studies deal with high doses, and the potential hazard of Pb at low concentrations is largely unknown. Given its well-demonstrated translational value for human toxicity research, we used zebrafish as a model species. Embryos were exposed to two environmentally relevant concentrations of lead (2.5 and 5 µg/L) from 6 h post-fertilization and analyzed after 48, 96, and 144 h. The morphological abnormality arose after 48 h, and the incidence and intensity were dose and time dependent. Spinal and tail deformities were the most frequently detected alterations. Pb also modulated the expression of genes involved in the toxicological responses (sod and mt), thus demonstrating that zebrafish’s early stages are able to mount an adaptive response. Moreover, ldh and β-catenin were significantly upregulated in all groups, whereas wnt3 expression was increased in the high concentration group. Our results confirm that zebrafish embryos and larvae are valuable early warning indicators of pollution and may play a major role in ecosystems and human health monitoring.
Effect of Non-Homogeneous Soil Characteristics on Substation Grounding-Grid Performances: A Review
Authors: Permal Navinesshani , Osman Miszaina , Ariffin Azrul Mohd , Abidin Ab Kadir Mohd Zainal
Published: August 2021

Designing an effective grounding system for AC substations needs predetermination of ground resistance and ground potential distribution caused by fault current’s presence in the ground. Therefore, it is necessary to have a suitable grounding grid structure in the soil properties in which the grid is buried. Though the soil composition where the grounding grid is located is typically non-homogeneous, the soil is often presumed to be homogeneous due to the complexities of grounding system analysis in non-homogeneous soil. This assumption will lead to inaccuracies in the computation of ground resistance and ground potentials. Although extensive research has been done on non-homogeneous soil structure, comprehensive literature on grounding system performance in non-homogeneous soil is yet to be reviewed. Thus, this paper reviews the effect of non-homogeneous soil on the grounding system, with different soil characteristics in horizontal and vertical two-layer soil structure and the horizontal three-layer soil structure. In addition, the effect of design parameters on the grounding performance in non-homogeneous soil conditions for non-transient fault conditions is also studied. The significance of this study is that it provides a comprehensive review of grounding performance as grounding design changes and their effects as soil layers and their corresponding features change. This knowledge will be useful in developing safe grounding designs in non-homogeneous soil.
Subtitling 3D VR Content with Limited 6DoF: Presentation Modes and Guiding Methods
Authors: Montagud Mario , Hurtado Cristian , De Rus Juan Antonio , Fernández Sergi
Published: August 2021

All multimedia services must be accessible. Accessibility for multimedia content is typically provided by means of access services, of which subtitling is likely the most widespread approach. To date, numerous recommendations and solutions for subtitling classical 2D audiovisual services have been proposed. Similarly, recent efforts have been devoted to devising adequate subtitling solutions for VR360 video content. This paper, for the first time, extends the existing approaches to address the challenges remaining for efficiently subtitling 3D Virtual Reality (VR) content by exploring two key requirements: presentation modes and guiding methods. By leveraging insights from earlier work on VR360 content, this paper proposes novel presentation modes and guiding methods, to not only provide the freedom to explore omnidirectional scenes, but also to address the additional specificities of 3D VR compared to VR360 content: depth, 6 Degrees of Freedom (6DoF), and viewing perspectives. The obtained results prove that always-visible subtitles and a novel proposed comic-style presentation mode are significantly more appropriate than state-of-the-art fixed-positioned subtitles, particularly in terms of immersion, ease and comfort of reading, and identification of speakers, when applied to professional pieces of content with limited displacement of speakers and limited 6DoF (i.e., users are not expected to navigate around the virtual environment). Similarly, even in such limited movement scenarios, the results show that the use of indicators (arrows), as a guiding method, is well received. Overall, the paper provides relevant insights and paves the way for efficiently subtitling 3D VR content.
The Thermo-Pressure Concept: A New Model in Diabetic Foot Risk Stratification
Authors: Perren Sarah , Formosa Cynthia , Camilleri Liberato , Chockalingam Nachiappan , Gatt Alfred
Published: August 2021

Elevated foot pressure and high temperatures have been proposed as predictive factors for diabetic foot ulceration; however, on their own, their predictive value is still questionable. This pilot study hypothesized that combining these two measurements in a thermo-pressure model could result in a more reliable risk assessment tool for providing risk categorization aimed to determine whether there is a correlation between foot plantar pressure and temperature in patients living with diabetes mellitus (DM) when compared with healthy individuals following a 15 min walk. Foot pressure and thermographic images were taken from 48 participants who were categorised into four groups following clinical evaluation into healthy individuals (Group A), living with DM with no complications (Group B), DM with peripheral arterial disease (Group C) and DM patients with neuropathy (Group D). This study demonstrated a positive correlation between pressure and temperature; as pressure increases, so does temperature. This was more pronounced in the groups with DM when compared to the healthy group. More research is warranted to further develop this innovative thermo-pressure model, which could hopefully be more sensitive in categorizing and identifying patients living with DM who are at risk of developing foot ulceration to initiate prompt care.
Two- and Three-Dimensional Numerical Investigation of the Influence of Holes on the Fatigue Crack Growth Path
Authors: Fageehi Yahya Ali
Published: August 2021

Problems in fracture mechanics are difficult when the appropriate analysis is unspecified, which is very common in most real-life situations. Finite element modeling is thus demonstrated to be an essential technique to overcome these problems. There are currently various software tools available for modeling fracture mechanics problems, but they are usually difficult to use, and obtaining accurate results is not an obvious task. This paper illustrates some procedures in two finite element programs to solve problems in two- and three-dimensional linear-elastic fracture mechanics, and an educational proposal is made to use this software for a better understanding of fracture mechanics. Crack modeling was done in a variety of ways depending on the software. The first is the well-known ANSYS, which is usually utilized in industry, and the second was a freely distributed code, called FRANC2D/L, from Cornell University. These software applications were used to predict the fatigue crack growth path as well as the associated stress intensity factors. The predicted results demonstrate that the fatigue crack is turned towards the hole. The fatigue crack growth paths are influenced by the varying positions and sizes of single holes, while two symmetrically distributed holes have no effect on the fatigue crack growth direction. The findings of the study agree with other experimental crack propagation studies presented in the literature that reveal similar crack propagation trajectory observations.
Use of Linear Viscoelastic Functions to Estimate the Aging Resistance and Internal Structure of Bituminous Binders
Authors: Cappello Miriam , Polacco Giovanni , Crépier Julien , Hung Yvong , Filippi Sara
Published: August 2021

Rheology is the most widely used technique to evaluate the performance and aging of bituminous binders. Since there are many available rheological tests, there is also a wide range of aging indexes and it is not easy to choose the most appropriate one, because a single value may hardly be adequate for different properties or operating conditions. In order to generalize the usefulness of an index, a good starting point is deriving it from a set of data, such as the master curves of linear viscoelastic functions. Then, the problem is the quantification of aging in a single numerical value from continuous curves, covering a wide range of frequencies/temperatures. In this work, a summary of the aging indexes derived from the master curves is reported and discussed. The indexes are applied to a bituminous binder either with or without the addition of an organo-modified layered silicate. The apparent molecular weight distributions and relaxation spectra were also calculated from the master curves and used to characterize the effect of aging on the binder properties and structure. In this way, an interesting parallelism was observed between the SARA fractions and the populations derived from a deconvolution analysis of the apparent molecular weight distributions.
Effect of the Passive Ultrasonic Irrigation and the Apical Diameter Size on the Debridement Efficacy of Infected Root Canals: A Multivariate Statistical Assessment of Histological Data
Authors: Alcota Marcela , Osorio Jimena , Díaz Claudia , Ortega-Pinto Ana , Peñafiel Cristián , Rivera Juan C. , Salazar Daniela , Manríquez Germán , González Fermín E.
Published: August 2021

The removal of necrotic and vital pulp substrates and microorganisms and their toxins from the root canal system (RCS) has been found to be the basis for a successful endodontic treatment. In this study, our aim was to evaluate the effect of passive ultrasonic irrigation (PUI) on the elimination of the organic remnant tissue from infected, narrow and curved mandibular root canals during their instrumentation. For this purpose, mesiobuccal canals from mandibular first molars were instrumented with the RaCe rotary system, using PUI activation or conventional irrigation (CI) and two apical diameters (#25 and #35). The root canal cleanness of the samples was evaluated by microscopy and using a modified Langeland’s ordinal scale. Parametric and non-parametric statistical analyses and principal coordinates analysis (PCoA) of the samples were performed. When PUI was used, there was a significant reduction of the organic remnant in the apical enlargement of 25 at 2 mm from the apex (p < 0.001). After pooling the groups, regardless of the depth of the observation (2 and 4 mm from the apex), the pair #35 + PUI vs. #25 + CI showed statistically significant differences (p < 0.001). The effect of PUI explained 65% of the overall variance when compared with the CI samples. The use of PUI reduced the organic material of narrow infected and curved root canals with an apical enlargement of #25 and #35. When PUI is not used, a biomechanical instrumentation up to a diameter ≥#35 is recommended.
The Representation of the Southern Annular Mode Signal in the Brazilian Earth System Model
Authors: Prado Luciana F. , Wainer Ilana , de Souza Ronald B.
Published: August 2021

The Southern Annular Mode (SAM, also known as the Antarctic Oscillation—AAO) explains most of the climate variability in the Southern Hemisphere. A ring pattern in mean sea level pressure (MSLP) or 500 hPa geopotential height around Antarctica characterizes SAM. Differences of MSLP values between SH mid and high latitudes define positive and negative SAM phases with impacts on mean atmospheric circulation. Thus, investigating how different models represent SAM is of paramount importance, as it can improve their ability to describe or even predict most of the SH climate variability. Here we examine how the Brazilian Earth System Model (BESM) represents SAM’s signal compared with observations, reanalysis, and other climate models contributing to the Coupled Modeling Intercomparison Project version 5 (CMIP5). We also evaluate how SAM relates to the South American surface temperature and precipitation and discuss the models’ limitations and biases compared with reanalysis data.
Effects of n-3 Polyunsaturated Fatty Acid-Enriched Hen Egg Consumption on the Inflammatory Biomarkers and Microvascular Function in Patients with Acute and Chronic Coronary Syndrome—A Randomized Study
Authors: Ćurić Željka Breškić , Masle Ana Marija , Kibel Aleksandar , Selthofer-Relatić Kristina , Stupin Ana , Mihaljević Zrinka , Jukić Ivana , Stupin Marko , Matić Anita , Kozina Nataša , Šušnjara Petar , Juranić Brankica , Kolobarić Nikolina , Šerić Vatroslav , Drenjančević Ines
Published: August 2021

This study aimed to test the effect of n-3 polyunsaturated fatty acid (PUFA)-enriched hen egg consumption on serum lipid and free fatty acid profiles, inflammatory and oxidative stress biomarkers, and microvascular reactivity in patients with coronary artery disease (CAD). Forty CAD patients participated in this study. Of those, 20 patients had acute CAD (Ac-CAD), and 20 patients had chronic CAD (Ch-CAD). The control group (N = 20) consumed three regular hen eggs/daily (249 mg n-3 PUFAs/day), and the n-3 PUFAs group (N = 20) consumed three n-3 PUFA-enriched hen eggs/daily (1053 g n-3 PUFAs/day) for 3 weeks. Serum n-3 PUFA concentration significantly increased (in all CAD patients), while LDL cholesterol and IL-6 (in Ac-CAD patients), and hsCRP and IL-1a (in all CAD patients) significantly decreased in the n-3 PUFAs group. Glutathione peroxidase (GPx) activity significantly decreased, and forearm skin microvascular reactivity in response to vascular occlusion (postocclusive reactive hyperemia (PORH)) remained unchanged in both the n-3 PUFAs and control groups in total CAD, Ac-CAD, and Ch-CAD patients. Potentially, n-3 PUFA-enriched hen eggs can change the free fatty acid profile to a more favorable lower n6/n3 ratio, and to exhibit mild anti-inflammatory effects but not to affect microvascular reactivity in CAD patients.
Cell Differentiation and Replication during Postnatal Development of the Murine First Molar
Authors: Balzano Rudi , Stellini Edoardo , Mucignat-Caretta Carla
Published: August 2021

Various signaling molecular pathways are involved in odontogenesis to promote cellular replication and differentiation. Tooth formation is controlled mainly by epithelial–mesenchymal interactions. The aim of this work was to investigate how cellular replication and differentiation ensue during the formation of the murine first molar in postnatal ages until eruption, focusing on morphogenesis, odontoblast differentiation and cellular replication. Wild-type CD1 mice were examined from birth to weaning. Morphogenesis and interaction between developing epithelial and mesenchymal tissues were evaluated in hematoxylin–eosin and Gomori trichome stained sections. Immunohistochemistry for nestin, which mediates the differentiation of odontoblasts, especially their polarization and elongation, showed that this intermediate filament was apparent already at postnatal day P1 in the apical region of odontoblasts and progressed apically from cusp tips, while it was not present in epithelial tissues. The expression of nuclear antigen Ki-67 highlighted dividing cells in both epithelial and mesenchymal tissues at P1, while one week later they were restricted to the cementoenamel junction, guiding root elongation. The link between odontoblast maturation and cellular replication in the different tooth tissues is essential to understand the development of tooth shape and dimension, to outline mechanisms of tooth morphogenesis and possibly eruption.
Prediction of Epilepsy Based on Tensor Decomposition and Functional Brain Network
Authors: Li Han , Zhang Qizhong , Lin Ziying , Gao Farong
Published: August 2021

Epilepsy is a chronic neurological disorder which can affect 65 million patients worldwide. Recently, network based analyses have been of great help in the investigation of seizures. Now graph theory is commonly applied to analyze functional brain networks, but functional brain networks are dynamic. Methods based on graph theory find it difficult to reflect the dynamic changes of functional brain network. In this paper, an approach to extracting features from brain functional networks is presented. Dynamic functional brain networks can be obtained by stacking multiple functional brain networks on the time axis. Then, a tensor decomposition method is used to extract features, and an ELM classifier is introduced to complete epilepsy prediction. In the prediction of epilepsy, the accuracy and F1 score of the feature extracted by tensor decomposition are higher than the degree and clustering coefficient. The features extracted from the dynamic functional brain network by tensor decomposition show better and more comprehensive performance than degree and clustering coefficient in epilepsy prediction.
Prognostic Value of Procalcitonin, C-Reactive Protein, and Lactate Levels in Emergency Evaluation of Cancer Patients with Suspected Infection
Authors: Chaftari Patrick , Qdaisat Aiham , Chaftari Anne-Marie , Maamari Julian , Li Ziyi , Lupu Florea , Raad Issam , Hachem Ray , Calin George , Yeung Sai-Ching Jim
Published: August 2021

Cancer patients have increased risk of infections, and often present to emergency departments with infection-related problems where physicians must make decisions based on a snapshot of the patient’s condition. Although C-reactive protein, procalcitonin, and lactate are popular biomarkers of sepsis, their use in guiding emergency care of cancer patients with infections is unclear. Using these biomarkers, we created a prediction model for short-term mortality in cancer patients with suspected infection. We retrospectively analyzed all consecutive patients who visited the emergency department of MD Anderson Cancer Center between 1 April 2018 and 30 April 2019. A clinical decision model was developed using multiple logistic regression for various clinical and laboratory biomarkers; coefficients were used to generate a prediction score stratifying patients into four groups according to their 14-day mortality risk. The prediction score had an area under the receiver operating characteristic curve value of 0.88 (95% confidence interval 0.85–0.91) in predicting 14-day mortality. The prediction score also accurately predicted intensive care unit admission and 30-day mortality. Our simple new scoring system for mortality prediction, based on readily available clinical and laboratory data, including procalcitonin, C-reactive protein, and lactate, can be used in emergency departments for cancer patients with suspected infection.
The Pathophysiology and the Therapeutic Potential of Cannabinoids in Prostate Cancer
Authors: Singh Kanika , Nassar Nazim , Bachari Ava , Schanknecht Ellen , Telukutla Srinivasareddy , Zomer Roby , Piva Terrence J. , Mantri Nitin
Published: August 2021

Prostate cancer is the second most frequently occurring cancer diagnosed among males. Recent preclinical evidence implicates cannabinoids as powerful regulators of cell growth and differentiation. In this review, we focused on studies that demonstrated anticancer effects of cannabinoids and their possible mechanisms of action in prostate cancer. Besides the palliative effects of cannabinoids, research from the past two decades has demonstrated their promising potential as antitumor agents in a wide variety of cancers. This analysis may provide pharmacological insights into the selection of specific cannabinoids for the development of antitumor drugs for the treatment of prostate cancer.
Chiral Synthesis of 3-Amino-1-phenylbutane by a Multi-Enzymatic Cascade System
Authors: Alcover Natàlia , Álvaro Gregorio , Guillén Marina
Published: August 2021

Asymmetric synthesis of chiral amines from prochiral ketones using transaminases is an attractive biocatalytic strategy. Nevertheless, it is hampered by its unfavorable thermodynamic equilibrium. In the present work, an insitu by-product removal strategy was applied for the synthesis of 3-amino-1-phenylbutane (3-APB) by coupling a transaminase with a pyruvate decarboxylase (PDC), which does not require the use of any expensive additional cofactor. Using this strategy, the pyruvate obtained in the transamination reaction is transformed by PDC into acetaldehyde and CO2 which are of high volatility. Two different transaminases from Chromobacterium violaceum (CviTA) and Vibrio fluvialis (VflTA) were characterized to find out the appropriate pH conditions. In both cases, the addition of PDC dramatically enhanced 3-APB synthesis. Afterwards, different reaction conditions were tested to improve reaction conversion and yield. It was concluded that 30 °C and a 20-fold alanine excess lead to the best process metrics. Under the mentioned conditions, yields higher than 60% were reached with nearly 90% selectivity using both CviTA and VflTA. Moreover, high stereoselectivity for (S)-3-APB was obtained and ee of around 90% was achieved in both cases. For the first time, the asymmetric synthesis of 3-APB using PDC as by-product removal system using CviTA is reported.
Immobilization of Potassium-Based Heterogeneous Catalyst over Alumina Beads and Powder Support in the Transesterification of Waste Cooking Oil
Authors: Lokman NolHakim Muhammad Amirrul Hakim , Shohaimi Norshahidatul Akmar Mohd , Mokhtar Wan Nur Aini Wan , Ibrahim Mohd Lokman , Abdullah Rose Fadzilah
Published: August 2021

In this work, the beads and powder potassium hydroxide (KOH) and potassium carbonate (K2CO3) supported on alumina oxide (Al2O3) were successfully prepared via incipient wetness impregnation technique. Herein, the perforated hydrophilic materials (PHM) made from low-density polyethylene (LDPE) was used as the catalyst reactor bed. The prepared catalysts were investigated using TGA, XRD, BET, SEM-EDX, TPD, FTIR while spent catalysts were analyzed using XRF and ICP-AES to study its deactivation mechanism. The catalytic performance of beads and powder KOH/Al2O3 and K2CO3/Al2O3 catalysts were evaluated via transesterification of waste cooking oil (WCO) to biodiesel. It was found that the optimum conditions for transesterification reaction were 1:12 of oil-to-methanol molar ratio and 5 wt.% of catalyst at 65 °C. As a result, the mesoporous size of beads KOH/Al2O3 and K2CO3/Al2O3 catalysts yielded 86.8% and 77.3% at 2 h’ reaction time of fatty acids methyl ester (FAME), respectively. It was revealed that the utilization of PHM for beads K2CO3/Al2O3 increase the reusability of the catalyst up to 7 cycles. Furthermore, the FAME produced was confirmed by the gas chromatography-mass spectroscopic technique. From this finding, beads KOH/Al2O3 and K2CO3/Al2O3 catalysts showed a promising performance to convert WCO to FAME or known as biodiesel.
Preparation and Application of 2D MXene-Based Gas Sensors: A Review
Authors: Li Qingting , Li Yanqiong , Zeng Wen
Published: August 2021

Since MXene (a two-dimensional material) was discovered in 2011, it has been favored in all aspects due to its rich surface functional groups, large specific surface area, high conductivity, large porosity, rich organic bonds, and high hydrophilicity. In this paper, the preparation of MXene is introduced first. HF etching was the first etching method for MXene; however, HF is corrosive, resulting in the development of the in situ HF method (fluoride + HCl). Due to the harmful effects of fluorine terminal on the performance of MXene, a fluorine-free preparation method was developed. The increase in interlayer spacing brought about by adding an intercalator can affect MXene’s performance. The usual preparation methods render MXene inevitably agglomerate and the resulting yields are insufficient. Many new preparation methods were researched in order to solve the problems of agglomeration and yield. Secondly, the application of MXene-based materials in gas sensors was discussed. MXene is often regarded as a flexible gas sensor, and the detection of ppb-level acetone at room temperature was observed for the first time. After the formation of composite materials, the increasing interlayer spacing and the specific surface area increased the number of active sites of gas adsorption and the gas sensitivity performance improved. Moreover, this paper discusses the gas-sensing mechanism of MXene. The gas-sensing mechanism of metallic MXene is affected by the expansion of the lamellae and will be doped with H2O and oxygen during the etching process in order to become a p-type semiconductor. A p-n heterojunction and a Schottky barrier forms due to combinations with other semiconductors; thus, the gas sensitivities of composite materials are regulated and controlled by them. Although there are only several reports on the application of MXene materials to gas sensors, MXene and its composite materials are expected to become materials that can effectively detect gases at room temperature, especially for the detection of NH3 and VOC gas. Finally, the challenges and opportunities of MXene as a gas sensor are discussed.
Application of Metal-Organic Framework-Based Composites for Gas Sensing and Effects of Synthesis Strategies on Gas-Sensitive Performance
Authors: Huang Bo , Li Yanqiong , Zeng Wen
Published: August 2021

Gas sensing materials, such as semiconducting metal oxides (SMOx), carbon-based materials, and polymers have been studied in recent years. Among of them, SMOx-based gas sensors have higher operating temperatures; sensors crafted from carbon-based materials have poor selectivity for gases and longer response times; and polymer gas sensors have poor stability and selectivity, so it is necessary to develop high-performance gas sensors. As a porous material constructed from inorganic nodes and multidentate organic bridging linkers, the metal-organic framework (MOF) shows viable applications in gas sensors due to its inherent large specific surface area and high porosity. Thus, compounding sensor materials with MOFs can create a synergistic effect. Many studies have been conducted on composite MOFs with three materials to control the synergistic effects to improve gas sensing performance. Therefore, this review summarizes the application of MOFs in sensor materials and emphasizes the synthesis progress of MOF composites. The challenges and development prospects of MOF-based composites are also discussed.
Nitrogen Dioxide Gas Sensor Based on Ag-Doped Graphene: A First-Principle Study
Authors: Li Qichao , Liu Yamin , Chen Di , Miao Jianmin , Zhi Xiao , Deng Shengwei , Lin Shujing , Jin Han , Cui Daxiang
Published: August 2021

High-performance tracking trace amounts of NO2 with gas sensors could be helpful in protecting human health since high levels of NO2 may increase the risk of developing acute exacerbation of chronic obstructive pulmonary disease. Among various gas sensors, Graphene-based sensors have attracted broad attention due to their sensitivity, particularly with the addition of noble metals (e.g., Ag). Nevertheless, the internal mechanism of improving the gas sensing behavior through doping Ag is still unclear. Herein, the impact of Ag doping on the sensing properties of Graphene-based sensors is systematically analyzed via first principles. Based on the density-functional theory (DFT), the adsorption behavior of specific gases (NO2, NH3, H2O, CO2, CH4, and C2H6) on Ag-doped Graphene (Ag–Gr) is calculated and compared. It is found that NO2 shows the strongest interaction and largest Mulliken charge transfer to Ag–Gr among these studied gases, which may directly result in the highest sensitivity toward NO2 for the Ag–Gr-based gas sensor.
Transportation Network Companies: Drivers’ Perceptions of Ride-Sharing Regarding Climate Change and Extreme Weather
Authors: Brugger Sandra Olivia , Watts Theresa
Published: August 2021

The transportation sector is a major factor contributing to climate change. Transportation Network Companies (TNC) may become part of solutions to reduce emissions and their drivers play an important role in doing so. This study aims to understand TNC driver’s perceptions of climate change, to understand how climate change and extreme weather affects their business and how they see their role in contributing to or mitigating climate change. We conducted an in-person survey of TNC drivers in Nevada, USA, and analyzed the derived information with descriptive statistics and content analysis. Among the 75 TNC drivers, almost half believe climate change is happening and is caused by human activities. We found TNC drivers and their business are affected by extreme weather events. Currently the drivers do not see their role in mitigating climate change and lack the awareness of green initiatives already in place by TNCs’. We conclude that TNCs could increase their climate change responsibility by providing driver incentives for cars with reduced emissions or by geographically expanding customer incentives for using sustainable TNC options such as car-pooling. By doing so, TNC may play a role in reducing global greenhouse gas emissions and traffic congestion; thus, contributing to improved sustainable transportation practices.
Effect of Saline Water for Drip Irrigation on Microbial Diversity and on Fertility of Aeolian Sandy Soils
Authors: Yu Xiangxiang , Jin Zhengzhong , Wang Haifeng
Published: August 2021

Saline water is widely distributed in the arid environment and sometimes represents the only source of irrigation water to restore and reconstruct vegetation. However, the effects of saline water on the bacterial diversity and fertility level of aeolian sandy soil are not well understood. In this study, we investigated a vegetation belt along the Tarim Desert Highway that has been constructed as a windbreak and consists of desert shrubs and was irrigated with saline water at six levels of salinity along the Tarim Desert Highway. The bacterial diversity was studied using Biolog Eco, a phospholipid fatty acid analysis, and a polymerase chain reaction–denaturing gradient gel electrophoresis, and the soil fertility was calculated and expressed as the integrated fertility index. The soil bacterial diversity (in terms of carbon metabolism, genes, and fatty acid species) was significantly affected by the level of salinity, and the microbial activity was low under high salinity. Fertility was also markedly affected by the degree of salinity and by the depth of soil, being lower at higher salinity levels and in the top layer (0–5 cm), and was also correlated to both the metabolic diversity index of soil microorganisms and the diversity index of fatty acids of soil microorganisms. The genetic diversity index of soil microorganisms shared a polynomial relation with fertility and contributed to it positively and significantly. Therefore, using less saline water for drip irrigation could avoid salt accumulation in soil and arrest its compaction, promote the formation of soil aggregates and the build-up of nutrients, and increase microbial activity, thus playing a crucial role in promoting the circulation, conversion, and utilization of nutrients in aeolian sandy soils and improving the soil quality. The judicious use of saline water, therefore, deserves serious consideration in irrigation practices.
Country-Specific Interests towards Fall Detection from 2004–2021: An Open Access Dataset and Research Questions
Authors: Thakur Nirmalya , Han Chia Y.
Published: August 2021

Falls, which are increasing at an unprecedented rate in the global elderly population, are associated with a multitude of needs such as healthcare, medical, caregiver, and economic, and they are posing various forms of burden on different countries across the world, specifically in the low- and middle-income countries. For these respective countries to anticipate, respond, address, and remedy these diverse needs either by using their existing resources, or by developing new policies and initiatives, or by seeking support from other countries or international organizations dedicated to global public health, the timely identification of these needs and their associated trends is highly necessary. This paper addresses this challenge by presenting a study that uses the potential of the modern Internet of Everything lifestyle, where relevant Google Search data originating from different geographic regions can be interpreted to understand the underlining region-specific user interests towards a specific topic, which further demonstrates the public health need towards the same. The scientific contributions of this study are two-fold. First, it presents an open-access dataset that consists of the user interests towards fall detection for all the 193 countries of the world studied from 2004–2021. In the dataset, the user interest data is available for each month for all these countries in this time range. Second, based on the analysis of potential and emerging research directions in the interrelated fields of Big Data, Data Mining, Information Retrieval, Natural Language Processing, Data Science, and Pattern Recognition, in the context of fall detection research, this paper presents 22 research questions that may be studied, evaluated, and investigated by researchers using this dataset.
In-Situ Cartilage Functionality Assessment Based on Advanced MRI Techniques and Precise Compartmental Knee Joint Loading through Varus and Valgus Stress
Authors: Said Oliver , Schock Justus , Abrar Daniel Benjamin , Schad Philipp , Kuhl Christiane , Nolte Teresa , Knobe Matthias , Prescher Andreas , Truhn Daniel , Nebelung Sven
Published: August 2021

Stress MRI brings together mechanical loading and MRI in the functional assessment of cartilage and meniscus, yet lacks basic scientific validation. This study assessed the response-to-loading patterns of cartilage and meniscus incurred by standardized compartmental varus and valgus loading of the human knee joint. Eight human cadaveric knee joints underwent imaging by morphologic (i.e., proton density-weighted fat-saturated and 3D water-selective) and quantitative (i.e., T1ρ and T2 mapping) sequences, both unloaded and loaded to 73.5 N, 147.1 N, and 220.6 N of compartmental pressurization. After manual segmentation of cartilage and meniscus, morphometric measures and T2 and T1ρ relaxation times were quantified. CT-based analysis of joint alignment and histologic and biomechanical tissue measures served as references. Under loading, we observed significant decreases in cartilage thickness (p < 0.001 (repeated measures ANOVA)) and T1ρ relaxation times (p = 0.001; medial meniscus, lateral tibia; (Friedman test)), significant increases in T2 relaxation times (p ≤ 0.004; medial femur, lateral tibia; (Friedman test)), and adaptive joint motion. In conclusion, varus and valgus stress MRI induces meaningful changes in cartilage and meniscus secondary to compartmental loading that may be assessed by cartilage morphometric measures as well as T2 and T1ρ mapping as imaging surrogates of tissue functionality.
Anomaly Detection of Operating Equipment in Livestock Farms Using Deep Learning Techniques
Authors: Park Hyeon , Park Daeheon , Kim Sehan
Published: August 2021

In order to establish a smart farm, many kinds of equipment are built and operated inside and outside of a pig house. Thus, the environment for livestock (limited to pigs in this paper) in the barn is properly maintained for its growth conditions. However, due to poor environments such as closed pig houses, lack of stable power supply, inexperienced livestock management, and power outages, the failure of these environment equipment is high. Thus, there are difficulties in detecting its malfunctions during equipment operation. In this paper, based on deep learning, we provide a mechanism to quickly detect anomalies of multiple equipment (environmental sensors and controllers, etc.) in each pig house at the same time. In particular, environmental factors (temperature, humidity, CO2, ventilation, radiator temperature, external temperature, etc.) to be used for learning were extracted through the analysis of data accumulated for the generation of predictive models of each equipment. In addition, the optimal recurrent neural network (RNN) environment was derived by analyzing the characteristics of the learning RNN. In this way, the accuracy of the prediction model can be improved. In this paper, the real-time input data (only in the case of temperature) was intentionally induced above the threshold, and 93% of the abnormalities were detected to determine whether the equipment was abnormal.
Harmonics Reduction and Reactive Power Injection in Wind Generation Systems
Authors: Rodarte Gutiérrez Francisco Emilio , Carranza Castillo Oscar , Rodríguez Rivas Jaime José , Ortega González Rubén , Peralta Sánchez Edgar , González Morales Luis Gerardo
Published: August 2021

In this work, methods are implemented to improve two aspects of energy quality in a wind generation system. First, the harmonic reduction is achieved by applying a linear control technique in the Grid Side Converter; and second, the power factor of the wind generation system using a Doubly Fed Induction Generator (DFIG) is adjusted by injecting reactive power. The reduction of the harmonic content is performed with a digital resonant controller, which tracks the periodic signals corresponding to the current harmonics of the Grid Side Converter (GSC), which is part of a “back to back” converter in a wind generation system. This technique allows implementing a current controller of the GSC with a high level of rejection of current harmonics, of frequencies with orders (1 + 6k) and (1 − 6k) (where k is an integer), when executed in the synchronous reference frame (dq). The purpose of this work is to inject currents to the grid with very low harmonic distortion and provide a method for tuning the resonant controller for a simple L filter; also, the GSC is used to generate reactive power. These two improvements achieve a unity power factor, and this is necessary to comply with the new codes where a leading power factor helps regulate the grid voltage.
A Dataset Quality Assessment—An Insight and Discussion on Selected Elements of Environmental Footprints Methodology
Authors: Lewandowska Anna , Joachimiak-Lechman Katarzyna , Kurczewski Przemysław
Published: August 2021

One of the most recently developed life cycle-based methods is an environmental footprint of products and organisations established by the European Commission. A special procedure of data and dataset quality assessment has been developed as a part of the environmental footprints methodology. The procedure may be recognised as vital and powerful but, at the same time, a bit complicated and time-consuming. It is worth discussing this subject and looking for potential simplification. In this paper, we suggest a possible way for simplification. We propose to remove an impact-assessment-based step from the procedure of company-specific datasets quality assessment. There are two potential benefits: a reduction in the need for expert knowledge and time savings. The threats posed are connected to the fact that all data influences the Data Quality Rating indicator of the entire dataset to the same degree. With a higher volume of data included in the assessment, there is a risk of greater differentiation in their quality. In this paper, an example of raw milk production is presented. The assessment of quality of the dataset was performed in three variants: pursuant to the approach established by the European Commission in the pilot phase, transition phase and with certain modifications employed.
A Dynamic Linkage between Financial Development, Energy Consumption and Economic Growth: Evidence from an Asymmetric and Nonlinear ARDL Model
Authors: Khan Imran , Rehman Faheem Ur , Pypłacz Paula , Khan Muhammad Asif , Wiśniewska Agnieszka , Liczmańska-Kopcewicz Katarzyna
Published: August 2021

Developing countries, including Pakistan, need a considerable effort to withstand economic growth; however, these countries have to cope with greenhouse gases emission and other environmental concerns. Financial advancement gives rise to modern, sometimes even innovative and energy-efficient technologies and, thus, contributes to a decline in energy usage among market entities: organizations and households. The current study explores the nonlinear asymmetric relationship between economic growth (Y) and the selected exogenous variables in Pakistan by incorporating time series data spanning from 1971 to 2016. Economic growth was considered as a target variable, while energy consumption (EC), electric power consumption (EPC), financial development (FD), and energy imports (EM) were considered independent variables. To investigate cointegration among the given variables, a nonlinear ARDL bound testing approach was employed. BDS independence test was used to check the nonlinearity, and a structural break unit root test was used for testing data stationarity. The findings confirm the presence of co-integration in the selected variables. A symmetric unidirectional significant causality exists running from EPC to Y, while a bidirectional symmetric causality was found between FD and Y. In contrast, any negative shocks in EPC, FD, and EM were found to have a positive asymmetric effect on Y. Meanwhile, a neutral effect was found between EC and Y. The outcomes of this study can provide guidelines for future researchers and policymakers.