bluuebunny/crossref_metadata_2025 huggingface dataset:
Control of an Outer Rotor Doubly Salient Permanent Magnet Generator for Fixed Pitch kW Range Wind Turbine Using Overspeed Flux Weakening Operations
Authors: Remli Aziz , Guerroudj Cherif , Charpentier Jean-Frédéric , Kendjouh Tarek , Bracikowski Nicolas , L. Karnavas Yannis
Published: April 2023

This paper deals with the analysis of the dynamic performance of a generator with a doubly salient exterior rotor excited by permanent magnets inserted in the stator yoke. The electrical generator works at low speed and is devoted to a wind energy conversion system. Indeed, the studied generator is a robust high-torque machine and can be directly coupled to the turbine blades. It must therefore assure the energy conversion for wind speeds lower or higher than its base speed. In fact, the control technique used in this work covers the two main operating zones: below the base speed and above it. In the first case, the maximum torque per ampere control law is developed; however, when the base speed is reached, the flux decay control law is implemented and, consequently, the system works above the nominal conditions. Fuzzy logic controllers are employed to regulate direct and quadrature machine currents and DC voltage in order to obtain satisfactory regulation performances. The ensemble of the wind turbine and electrical machine with technical control is performed in Matlab/Simulink software. The simulation results obtained show the capability of the machine to operate at variable speeds, ensuring efficient energy conversion under and over the nominal speed.
Effect of Nitrogen Application Methods on Yield and Grain Quality of an Extremely Early Maturing Rice Variety
Authors: Yun Yeotae , Kim Gyucheol , Cho Giwon , Lee Youngju , Yun Tugsang , Kim Hakhun
Published: April 2023

This study aimed to investigate the effect of nitrogen application methods on the yield and grain quality of an extremely early maturing rice variety. The experiment was conducted in the rice research field of Chungnam Agricultural Research and Extension Services, South Korea, in 2019 and 2020. Two nitrogen application methods, BD (100% as a basal dressing) and BTD (70% as a basal dressing + 30% as a top dressing), with three different nitrogen levels (70 kg/ha, 90 kg/ha, and 110 kg/ha), were employed. The results showed that BD treatment had comparable or higher head rice yields and improved grain quality compared to BTD treatment at all nitrogen levels. Additionally, the SPAD value at heading date was highly correlated with both the protein content (r2 = 0.838**) and glossiness of cooked rice (r2 = 0.630**). Therefore, this study suggests that BD treatment could be an effective approach to improve the productivity and quality of extremely early maturing rice varieties while saving on labor costs, and the SPAD value can be used as an index to infer the taste of rice. In conclusion, this study provides useful insights into nitrogen application methods that can be used to enhance the yield and quality of extremely early maturing rice varieties.
Effect of Fertilization and Weed Management Practices on Weed Diversity and Hemp Agronomic Performance
Authors: Kousta Angeliki , Papastylianou Panayiota , Travlos Ilias , Mavroeidis Antonios , Kakabouki Ioanna
Published: April 2023

The industrial hemp market is rapidly expanding, and best crop practices need to be assessed. This study aimed to determine the effect of fertilization and weed management on hemp crops and weed flora during the 2019 and 2020 growing seasons. Field experiments were laid out in a split–split plot design with three replicates: two hemp cultivars as main plots, three fertilization treatments as sub-plots, and three sub-sub-plots (weedy, weed-free, and herbicide application). For the computation of crop traits, 10 plants were randomly selected by each plot. Weed species were collected by quadrate for density and biomass weight determination. Increased fertilization rate positively affected plant height and dry biomass, while no impact was recorded on yield and yield components. The density and biomass of nitrophilous weeds were enhanced by fertilization, negatively affecting hemp growth. Marked differences were recorded on the competitive ability of cultivars since “Fedora 17” decreased the weed studied traits better than “Uso 31”. Herbicide application decreased the biomass of annual and perennial weeds by 38% and 13%, respectively, while it caused a reduction in hemp growth and yield of “Uso 31” plants. Further research should be conducted to address hemp yield losses under different cultural practices and weed control systems.
Predator-Unfriendly Pesticides Harm the Beneficial Mite Neoseiulus idaeus Denmark & Muma (Acari: Phytoseiidae)
Authors: Barroso Geovanny , Godoy Lucas Lorena , Iost Filho Fernando Henrique , Yamada Mariana , Santana Emile Dayara Rabelo , Pazini Juliano de Bastos , de Queiroz Oliveira Luana Vitória , Yamamoto Pedro Takao
Published: April 2023

Pesticides are commonly used to control weeds, diseases, and pests in soybean crops, although natural enemies are also key components of integrated pest management programs protecting soybean from pests. The predatory mite Neoseiulus idaeus Denmark & Muma is commonly found in soybeans associated with tetranychid mites. We determined the compatibility of some pesticides used in Brazilian soybean fields with N. idaeus on the basis of their lethal and sub-lethal effects. We assessed the acute toxicity of pesticides that are considered harmless to females of N. idaeus and evaluated the effects on the mite offspring. Acephate as well as imidacloprid and bifenthrin were most toxic to adult females and were classified as harmful. Chlorfenapyr, indoxacarb, and the neonicotinoid and pyrethroid mixtures were classified as slightly to moderately harmful. Immatures of N. idaeus were able to develop and reach the adult stage when treated with chlorantraniliprole, flubendiamide, glyphosate, and teflubenzuron, but immature survival was reduced to 42 and 64% for offspring of females treated with chlorantraniliprole or teflubenzuron, respectively. Reproduction was most affected in females exposed to chlorantraniliprole and teflubenzuron; these females had daily oviposition rates of 0.5 and 0.4 egg/female/day, respectively, and mean fecundities of 2.7 and 5.8 eggs/female, respectively. On the basis of sublethal effects and life table parameters, chlorantraniliprole was classified as moderately harmful, while the other pesticides tested were classified as harmless. In considering the use of pesticides while targeting the conservation of N. idaeus as a predator of important pests in soybean crops, one must prioritize pesticides that will most likely have less harmful effects on this predator in the field.
Effects of Spectral Quality and Light Quantity of LEDs on In Vitro Shoot Development and Proliferation of Ananas comosus L. Merr
Authors: Cavallaro Valeria , Avola Giovanni , Fascella Giancarlo , Pellegrino Alessandra , Ierna Anita
Published: April 2023

Light intensity and spectrum have a direct effect on the growth and development of plants and on the qualitative characteristics of their productions. LED technology seems to offer interesting prospects for its possible use in confined environments (growth chambers, bioreactors, greenhouses, etc). On the basis of these considerations, we tested the effects on the in vitro growth and development of micropropagated pineapple (Ananas comosus (L.) Merr.) plantlets using four different light spectra: (1) fluorescence light (FL—control); (2) white LED (WL—blue 20%, green 36%, red 38%, far red 6%, and UV 1%); (3) predominantly red LED (RL—blue 12%, green 19%, red 61%, and far red 8%); (4) Red/Blue LED (RL/BL—67% red and 33% blue) and two light intensities: 80 and 100 μmol m−2s−1 (16/8 h light/dark photoperiod). A. comosus showed a different morphogenetic response to the light spectra and their intensity and to their interaction. Among the LED lights to date tested, at 80 μmol m−2s−1 the best results on shoot multiplication were obtained under the RL light and to a lesser extent under the WL. This last treatment resulted also in a significant improvement in shoot quality in terms of secondary shoot dry weight and total chlorophyll concentration when compared to all the other light spectra tested.
In Vitro Activity of Farnesol against Malassezia pachydermatis Isolates from Otitis Externa Cases in Dogs
Authors: Olabode Ifarajimi Rapheal , Sachivkina Nadezhda , Karamyan Arfenia , Mannapova Ramziya , Kuznetsova Olga , Bobunova Anna , Zhabo Natallia , Avdonina Marina , Gurina Regina
Published: April 2023

Chronic otitis externa of dogs is a significant problem due to the prevalence and complexity of the treatment of such animals. There is evidence that in 60–80% of cases of infectious diseases microorganisms located in the biofilm phenotype play the main role. Microorganisms in the biofilm phenotype have a number of advantages, the most significant of which is considered to be increased resistance to various external factors. Among them, a special place is occupied by resistance to antibiotics. In recent decades, research has been conducted at an increasing scale on the role of biofilm infections in various pathologies in veterinary medicine. The etiology and therapy of dog otitis externa caused by Malassezia pachydermatis biofilm has not been fully studied. This is why we consider relevant the scientific and practical aspects of research on the etiology and therapy of dog otitis externa from the position of biofilm infection. In this work, it has been statistically proven that there is a relationship between the optical density of Malassezia pachydermatis biofilms and their sensitivity to drugs, and this relationship is statistically significant. In addition, we have demonstrated that Farnesol has a good antibiofilm effect at a concentration of more 1.6 μM/mL (24% OD decrease of biofilm), and its highest antibiofilm effect (71–55%—more than a half) was observed at a concentration of 200–12.5 μM/mL.
Responses of Dairy Buffalo to Heat Stress Conditions and Mitigation Strategies: A Review
Authors: Petrocchi Jasinski Francesca , Evangelista Chiara , Basiricò Loredana , Bernabucci Umberto
Published: April 2023

Increases in temperature and the greater incidence of extreme events are the consequences of the climate change that is taking place on planet Earth. High temperatures create severe discomfort to animal farms as they are unable to efficiently dissipate their body heat, and for this, they implement mechanisms to reduce the production of endogenous heat (reducing feed intake and production). In tropical and subtropical countries, where buffalo breeding is more widespread, there are strong negative consequences of heat stress (HS) on the production and quality of milk, reproduction, and health. The increase in ambient temperature is also affecting temperate countries in which buffalo farms are starting to highlight problems due to HS. To counteract HS, it is possible to improve buffalo thermotolerance by using a genetic approach, but even if it is essential, it is a long process. Two other mitigation approaches are nutritional strategies, such as the use of vitamins, minerals, and antioxidants and cooling strategies such as shade, fans, sprinklers, and pools. Among the cooling systems that have been evaluated, wallowing or a combination of fans and sprinklers, when wallowing is not available, are good strategies, even if wallowing was the best because it improved the production and reproduction performance and the level of general well-being of the animals.
Biosecurity and Hygiene Procedures in Pig Farms: Effects of a Tailor-Made Approach as Monitored by Environmental Samples
Authors: Scollo Annalisa , Perrucci Alice , Stella Maria Cristina , Ferrari Paolo , Robino Patrizia , Nebbia Patrizia
Published: April 2023

In livestock, the importance of hygiene management is gaining importance within the context of biosecurity. The aim of this study was to monitor the implementation of biosecurity and hygiene procedures in 20 swine herds over a 12-month period, as driven by tailor-made plans, including training on-farm. The measure of adenosine triphosphate (ATP) environmental contents was used as an output biomarker. The presence of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) and extended-spectrum β-lactamase producing Escherichia coli (ESBL-E. coli) was also investigated as sentinels of antibiotic resistance. A significant biosecurity improvement (p = 0.006) and a reduction in the ATP content in the sanitised environment (p = 0.039) were observed. A cluster including 6/20 farms greatly improved both biosecurity and ATP contents, while the remaining 14/20 farms ameliorated them only slightly. Even if the ESBL-E. coli prevalence (30.0%) after the hygiene procedures significantly decreased, the prevalence of LA-MRSA (22.5%) was unaffected. Despite the promising results supporting the adoption of tailor-made biosecurity plans and the measure of environmental ATP as an output biomarker, the high LA-MRSA prevalence still detected at the end of the study underlines the importance of improving even more biosecurity and farm hygiene in a one-health approach aimed to preserve also the pig workers health.
Factor in Fear: Interference Competition in Polymorphic Spadefoot Toad Tadpoles and Its Potential Role in Disruptive Selection
Authors: Strugariu Alexandru , Martin Ryan Andrew
Published: April 2023

Disruptive selection arises when extreme phenotypes have a fitness advantage compared to more-intermediate phenotypes. Theory and evidence suggest that intraspecific resource competition is a key driver of disruptive selection. However, while competition can be indirect (exploitative) or direct (interference), the role of interference competition in disruptive selection has not been tested, and most models of disruptive selection assume exploitative competition. We experimentally investigated whether the type of competition affects the outcome of competitive interactions using a system where disruptive selection is common: Mexican spadefoot toads (Spea multiplicata). Spea tadpoles develop into alternative resource-use phenotypes: carnivores, which consume fairy shrimp and other tadpoles, and omnivores, which feed on algae and detritus. Tadpoles intermediate in phenotype have low fitness when competition is intense, as they are outcompeted by the specialized tadpoles. Our experiments revealed that the presence of carnivores significantly decreased foraging behavior in intermediate tadpoles, and that intermediate tadpoles had significantly lower growth rates in interference competition treatments with carnivores but not with omnivores. Interference competition may therefore be important in driving disruptive selection. As carnivore tadpoles are also cannibalistic, the ‘fear’ effect may have a greater impact on intermediate tadpoles than exploitative competition alone, similarly to non-consumptive effects in predator–prey or intraguild relationships.
Genomic Prediction Accuracies for Growth and Carcass Traits in a Brangus Heifer Population
Authors: Peters Sunday O. , Kızılkaya Kadir , Sinecen Mahmut , Mestav Burcu , Thiruvenkadan Aranganoor K. , Thomas Milton G.
Published: April 2023

The predictive abilities and accuracies of genomic best linear unbiased prediction (GBLUP) and the Bayesian (BayesA, BayesB, BayesC and Lasso) genomic selection (GS) methods for economically important growth (birth, weaning, and yearling weights) and carcass (depth of rib fat, apercent intramuscular fat and longissimus muscle area) traits were characterized by estimating the linkage disequilibrium (LD) structure in Brangus heifers using single nucleotide polymorphisms (SNP) markers. Sharp declines in LD were observed as distance among SNP markers increased. The application of the GBLUP and the Bayesian methods to obtain the GEBV for growth and carcass traits within k-means and random clusters showed that k-means and random clustering had quite similar heritability estimates, but the Bayesian methods resulted in the lower estimates of heritability between 0.06 and 0.21 for growth and carcass traits compared with those between 0.21 and 0.35 from the GBLUP methodologies. Although the prediction ability of the GBLUP and the Bayesian methods were quite similar for growth and carcass traits, the Bayesian methods overestimated the accuracies of GEBV because of the lower estimates of heritability of growth and carcass traits. However, GBLUP resulted in accuracy of GEBV for growth and carcass traits that parallels previous reports.
Impact of a Pro-Active Infectious Disease Consultation on the Management of a Multidrug-Resistant Organisms Outbreak in a COVID-19 Hospital: A Three-Months Quasi-Experimental Study
Authors: Bavaro Davide Fiore , De Gennaro Nicolò , Belati Alessandra , Diella Lucia , Papagni Roberta , Frallonardo Luisa , Camporeale Michele , Guido Giacomo , Pellegrino Carmen , Marrone Maricla , Dell’Erba Alessandro , Gesualdo Loreto , Brienza Nicola , Grasso Salvatore , Columbo Giuseppe , Moschetta Antonio , Carpagnano Giovanna Elisiana , Daleno Antonio , Minicucci Anna Maria , Migliore Giovanni , Saracino Annalisa
Published: April 2023

Background: Antimicrobial and diagnostic stewardship (AS/DS) principles are crucial for the management of multidrug-resistant organisms (MDROs) infections. We evaluated the impact of a pro-active Infectious Disease (ID) consultation on the mortality risk of patients during an MDROs outbreak in a COVID-19 hospital. Methods: A quasi-experimental study was performed in a dedicated COVID-19 hospital, including patients with suspected/confirmed infection and/or colonization by MDROs, which were managed as follows: (i) according to the standard of care during the pre-phase and (ii) in collaboration with a dedicated ID team performing a pro-active bedside evaluation every 48–72 h in the post-phase. Results: Overall, 112 patients were included (pre-phase = 89 and post-phase = 45). The AS interventions included the following: therapy optimization (33%), de-escalation to narrow the spectrum (24%) or to lessen toxic drugs (20%), and discontinuation of antimicrobials (64%). DS included the request of additional microbiologic tests (82%) and instrumental exams (16%). With the Cox model, after adjusting for age, sex, COVID-19 severity, infection source, etiological agents, and post-phase attendance, only age predicted an increased risk of mortality, while attendance in the post-phase resulted in a decreased risk of mortality. Conclusions: Implementation of AS and DS intervention through a pro-active ID consultation may reduce the risk of 28-day mortality of COVID-19 patients with MDROs infections.
Phytochemical Screening, GC-MS Analysis, and Evaluating In Vivo Antitrypanosomal Effects of a Methanolic Extract of Garcinia kola Nuts on Rats
Authors: Rufa’i Fatihu Ahmad , Baecker Daniel , Mukhtar Muhammad Dauda
Published: April 2023

Trypanosomiasis is a serious disease that affects both humans and animals, causing social and economic losses. Efforts to find new therapeutic approaches are warranted to improve treatment options. Therefore, the purpose of this communication includes the phytochemical screening of a methanolic extract of Garcinia kola nuts and the in vivo evaluation of its biological activity against rats infected with Trypanosoma brucei brucei and treated with 4 different concentrations of the extract (0.01, 0.1, 1, and 10 mg/kg). Treatment with suramin served as a positive control, while the negative control received no drug. Since the general toxicity of the extract could be ruled out, efficacy was evaluated based on physiological changes, such as induction of trypanosome parasitemia, influence on body temperature, and body weight. Survival was assessed during this study. Physical parameters, behavioral characteristics, and various hematological indices were also monitored. Based on the (patho)physiological and behavioral parameters (e.g., no parasitemia, no increase in body temperature, an increase in body weight, no loss of condition, no alopecia, and no gangrene), the efficacy of the extract was evident, which was also confirmed by 100% survival, while in the negative control, all rats died during the observation period. Since overall very similar results were obtained as a result of treatment with the established suramin, the in vivo antitrypanosomal activity of a methanolic extract of G. kola nuts on rats can be demonstrated in this communication. This opens the way, for example, for further development of drug formulations based on this methanolic extract.
Tobacco Seed-Based Oral Vaccination against Verocytotoxic O138 Escherichia coli as Alternative Approach to Antibiotics in Weaned Piglets
Authors: Rossi Luciana , Dell’Anno Matteo , Turin Lauretta , Reggi Serena , Lombardi Angela , Alborali Giovanni Loris , Filipe Joel , Riva Federica , Riccaboni Pietro , Scanziani Eugenio , Dall’Ara Paola , Demartini Eugenio , Baldi Antonella
Published: April 2023

Post-weaning diarrhoea and enterotoxaemia caused by Escherichia coli are serious threats in the pig (Sus scrofa domesticus) livestock industry and are responsible for economic losses related to mortality, morbidity and stunted growth. The aim of this study was to evaluate the effect of an engineered tobacco seeds-based edible vaccine in O138 Escherichia coli-challenged piglets throughout a multidisciplinary approach. Thirty-six weaned piglets were enrolled and randomly divided into two experimental groups, a control (C; n = 18) group and a tobacco edible vaccination group (T, n = 18), for 29 days of trial. At days 0, 1, 2, 5 and 14, piglets of the T group were fed with 10 g of the engineered tobacco seeds line expressing F18 and VT2eB antigens, while the C group received wild-type tobacco seeds. After 20 days, 6 piglets/group were orally challenged with the Escherichia coli O138 strain (creating four subgroups: UC = unchallenged control, CC = challenged control, UT = unchallenged tobacco, CT = challenged tobacco) and fed with a high protein diet for 3 consecutive days. Zootechnical, clinical, microbiological, histological and immunological parameters were assayed and registered during the 9 days of post-challenge follow up. At 29 days post-challenge, the CT group displayed a lower average of the sum of clinical scores compared to the CC group (p < 0.05), while the CC group showed a higher average sum of the faecal score (diarrhoea) (p < 0.05) than the CT group. A decreased number of days of shedding of the pathogenic strain was observed in the CT compared to the CC group (p < 0.05). Specific anti-F18 IgA molecules were significantly higher in the CT group compared to the CC group’s faecal samples during the post-challenge period (p < 0.01). In conclusion, edible vaccination with engineered tobacco seeds showed a protective effect on clinical symptoms and diarrhoea incidence during the post-challenge period, characterized by a limited time of pathogenic strain shedding in faeces.
Neonatal Brain Abscess with Serratia marcescens after Intrauterine Infection: A Case Report
Authors: Bizubac Mihaela , Balaci-Miroiu Francisca , Filip Cristina , Vasile Corina Maria , Herișeanu Carmen , Marcu Veronica , Stoica Sergiu , Cîrstoveanu Catalin
Published: April 2023

Brain abscesses are a possible complication of bacterial sepsis or central nervous system infection but are uncommon in the neonatal period. Gram-negative organisms often cause them, but Serratia marcescens is an unusual cause of sepsis and meningitis in this age group. This pathogen is opportunistic and frequently responsible for nosocomial infections. Despite the existing antibiotics and modern radiological tools, mortality and morbidity remain significant in this group of patients. We report an unusual unilocular brain abscess in a preterm neonate caused by Serratia marcescens. The infection had an intrauterine onset. The pregnancy was achieved through assisted human reproduction techniques. It was a high-risk pregnancy, with pregnancy-induced hypertension, imminent abortion, and required prolonged hospitalization of the pregnant woman with multiple vaginal examinations. The infant was treated with multiple antibiotic cures and percutaneous drainage of the brain abscess associated with local antibiotic treatment. Despite treatment, evolution was unfavorable, complicated by fungal sepsis (Candida parapsilosis) and multiple organ dysfunction syndrome.
Reverse Electron Transport at Mitochondrial Complex I in Ischemic Stroke, Aging, and Age-Related Diseases
Authors: Chavda Vishal , Lu Bingwei
Published: April 2023

Stroke is one of the leading causes of morbidity and mortality worldwide. A main cause of brain damage by stroke is ischemia-reperfusion (IR) injury due to the increased production of reactive oxygen species (ROS) and energy failure caused by changes in mitochondrial metabolism. Ischemia causes a build-up of succinate in tissues and changes in the mitochondrial NADH: ubiquinone oxidoreductase (complex I) activity that promote reverse electron transfer (RET), in which a portion of the electrons derived from succinate are redirected from ubiquinol along complex I to reach the NADH dehydrogenase module of complex I, where matrix NAD+ is converted to NADH and excessive ROS is produced. RET has been shown to play a role in macrophage activation in response to bacterial infection, electron transport chain reorganization in response to changes in the energy supply, and carotid body adaptation to changes in the oxygen levels. In addition to stroke, deregulated RET and RET-generated ROS (RET-ROS) have been implicated in tissue damage during organ transplantation, whereas an RET-induced NAD+/NADH ratio decrease has been implicated in aging, age-related neurodegeneration, and cancer. In this review, we provide a historical account of the roles of ROS and oxidative damage in the pathogenesis of ischemic stroke, summarize the latest developments in our understanding of RET biology and RET-associated pathological conditions, and discuss new ways to target ischemic stroke, cancer, aging, and age-related neurodegenerative diseases by modulating RET.
Implementation of the Mean Time to Failure Indicator in the Control of the Logistical Support of the Operation Process
Authors: Żyluk Andrzej , Zieja Mariusz , Grzesik Norbert , Tomaszewska Justyna , Kozłowski Grzegorz , Jasztal Michał
Published: April 2023

The focus of this paper is to identify a method for defining the needs of logistical operational support based on the mean time to failure (MTTF) factor. The research was based on a helicopter intended for flight training. The MTTF indicator for selected equipment was determined based on failure data from previous flight operations. As the basic operational data for the developed method, the time from the beginning of the operation or the flight time from the last damage and the method of restoring airworthiness were selected. The MTTF and replacement index for the device were determined. The next step was to determine the index, based on selected probability distributions. The results were analyzed and presented in graphical form, and conclusions were drawn. Based on the MTTF index and replacement index, the logistics needs of selected devices were determined. The obtained results were compared with the actual exchanges of devices made in the year in question. The research proved that the MTTF reliability factor and the analysis of trends in value changes could be used to determine the needs for the logistical security of the operation process, particularly in relation to the equipment subject to accidental failures. This is important for maintaining high availability of an aircraft or other technical objects.
Analysis of Acoustic Signal Propagation for Reliable Digital Communication along Exposed and Buried Water Pipes
Authors: Farai Omotayo , Metje Nicole , Anthony Carl , Chapman David
Published: April 2023

Wireless sensor networks (WSN) have emerged as a robust and cost-effective solution for buried pipeline monitoring due to the low cost (a maximum of a few tens of UK pounds (GBP)), low power supply capacity (in the order of 1 watt/hour) and small size (centimetre scale) requirements of the wireless sensor nodes. One of the main challenges for WSN deployment, however, is the limited range of underground data communication between the wireless sensor nodes of less than 3 m, which subsequently increases deployment costs for a utility owner for buried pipeline monitoring. A promising alternative to overcome this limitation is using low-frequency (<1 kHz) acoustic signal propagation along the pipe. This paper examines the feasibility of using low-frequency acoustic signal propagation along exposed and buried medium-density polyethylene (MDPE) pipes and makes predictions of the potential distances at which reliable data communication can be achieved. Quantification of the acoustic attenuation was performed using both analytical and numerical models in addition to laboratory and field experiments. The predicted acoustic data communication distance ranged between approximately 18 m for an exposed and approximately 11 m for a buried MDPE pipe. These results demonstrate the feasibility of using low-frequency acoustic signal propagation for achieving reliable wireless underground communication.
Selective Reagent Ion-Time-of-Flight-Mass Spectrometric Investigations of the Intravenous Anaesthetic Propofol and Its Major Metabolite 2,6-Diisopropyl-1,4-benzoquinone
Authors: Chawaguta Anesu , Weiss Florentin , Marotto Alessandro , Jürschik Simone , Mayhew Chris A.
Published: April 2023

The first detailed selected reagent ion-time-of-flight-mass spectrometric fundamental investigations of 2,6-diisopropylphenol, more commonly known as propofol (C12H18O), and its metabolite 2,6-diisopropyl-1,4-benzoquinone (C12H16O2) using the reagent ions H3O+, H3O+.H2O, O2+• and NO+ are reported. Protonated propofol is the dominant product ion resulting from the reaction of H3O+ with propofol up to a reduced electric field strength (E/N) of about 170 Td. After 170 Td, collision-induced dissociation leads to protonated 2-(1-methylethyl)-phenol (C9H13O+), resulting from the elimination of C3H6 from protonated propofol. A sequential loss of C3H6 from C9H13O+ also through collision-induced processes leads to protonated phenol (C6H7O+), which becomes the dominant ionic species at E/N values exceeding 170 Td. H3O+.H2O does not react with propofol via a proton transfer process. This is in agreement with our calculated proton affinity of propofol being 770 kJ mol−1. Both O2+• and NO+ react with propofol via a charge transfer process leading to two product ions, C12H18O+ (resulting from non-dissociative charge transfer) and C11H15O+ that results from the elimination of one of the methyl groups from C12H18O+. This dissociative pathway is more pronounced for O2+• than for NO+ throughout the E/N range investigated (approximately 60–210 Td), which reflects the higher recombination energy of O2+• (12.07 eV) compared to that of NO+ (9.3 eV), and hence the higher internal energy deposited into the singly charged propofol. Of the four reagent ions investigated, only H3O+ and H3O+.H2O react with 2,6-diisopropyl-1,4-benzoquinone, resulting in only the protonated parent at all E/N values investigated. The fundamental ion-molecule studies reported here provide underpinning information that is of use for the development of soft chemical ionisation mass spectrometric analytical techniques to monitor propofol and its major metabolite in the breath. The detection of propofol in breath has potential applications for determining propofol blood concentrations during surgery and for elucidating metabolic processes in real time.
Teletraffic Analysis of DoS and Malware Cyber Attacks on P2P Networks under Exponential Assumptions
Authors: Sánchez-Patiño Natalia , Gallegos-Garcia Gina , Rivero-Angeles Mario E.
Published: April 2023

Peer-to-peer (P2P) networks are distributed systems with a communication model in which no central authority governs the behavior of individual peers. These networks currently account for a considerable percentage of all bandwidth worldwide. However, this communication model also has a clear disadvantage: it has a multitude of vulnerabilities and security threats. The nature of the P2P philosophy itself means that there is no centralized server responsible for uploading, storing, and verifying the authenticity of the shared files and packets. A direct consequence of this is that P2P networks are a good choice for hackers for the spread of malicious software or malware in general since there is no mechanism to control what content is shared. In this paper, we present a mathematical model for P2P networks to study the effect of two different attacks on these systems, namely, malware and denial of service. To analyze the behavior of the cyber attacks and identify important weaknesses, we develop different Markov chains that reflect the main dynamics of the system and the attacks. Specifically, our model considers the case in which a certain number of nodes are infected with a cyber worm that is spread throughout the network as the file is shared among peers. This allows observation of the final number of infected peers when an initial number (we evaluate the system for from 1 to 14 initial nodes) of malicious nodes infect the system. For the DoS attack, our model considers the portion of peers that are unable to communicate and the average attack duration to study the performance degradation of such an attack. A two-pronged approach was used to study the impact of the attacks on P2P networks; the first focused only on the P2P network, and the second focused on the attacks and the network.
Research and Application of Key Technologies for the Construction of Cemented Material Dam with Soft Rock
Authors: Jia Jinsheng , Ding Lianying , Wu Yangfeng , Zhao Chun , Zhao Lei
Published: April 2023

In order to safely and efficiently use soft rock aggregate cemented dams in red bed regions and promote the development of widely sourced cemented sand and gravel dam materials, the Jinjigou project in China applied soft rock for the first time in the construction of cemented material dams. This article further explores the concept of cemented material dams from conducting on-site direct shear tests and research on soft rock material ratios and explores and invents a new structure and construction method by combining soft rock cemented sand and gravel with cemented rockfill. This article also proposes a digital mixing and intelligent dynamic control method for cemented material dams with soft rock. The research results show that soft rock aggregate content not exceeding 60% can produce soft rock cemented gravel with a compressive strength of no less than 6 MPa. The stress on the dam body is small and does not produce tensile stress. The dam body with added soft rock has certain shear-bearing capacity, with a shear friction coefficient of 0.99~1.10 MPa, cohesion of 0.26~0.53 MPa, and high residual strength, accounting for 60~80% of the peak strength. At the same time, the problems of large fluctuations in moisture content and the uneven grading of the soft rock and riverbed gravel mix during the mixing and production process, and the significant influence on safety caused by the large strength dispersion of the cemented sand and gravel, are resolved, ensuring the quality of soft rock cemented sand and gravel preparation. The successful application of soft rock cemented material dams in Jinjigou has achieved a breakthrough in key technologies for soft rock cemented dam construction in red bed regions, proving the feasibility of soft rock cemented material dam construction and having broad prospects for application and promotion.
Simultaneous Phosphate Removal and Power Generation by the Aluminum–Air Fuel Cell for Energy Self-Sufficient Electrocoagulation
Authors: Han Xiaoyu , Qi Hanlin , Qu Youpeng , Feng Yujie , Zhao Xin
Published: April 2023

A self-powered electrocoagulation system with a single-chamber aluminum–air fuel cell was employed for phosphate removal in this study. Electricity production and aluminum hydroxides in solution were also investigated. When the NaCl concentration increased from 2 mmol/L to 10 mmol/L, the phosphate removal increased from 86.9% to 97.8% in 60 min. An electrolyte composed of 10 mmol/L of NaCl was shown to obtain a maximum power density generation of 265.7 mW/m2. When the initial solution pH ranged from 5.0 to 9.0, 98.5% phosphate removal and a maximum power density of 338.1 mW/m2 were obtained at pH 6.0. Phosphate was mainly removed by aluminum hydroxide adsorption. These results demonstrate that the aluminum–air fuel cell can be applied as electricity-producing electrocoagulation equipment. Aluminum–air fuel cells provide an alternative method to meet the goal of carbon neutrality in wastewater treatment compared with traditional energy-consuming electrocoagulation systems.
Isolation and Characterization of Brucella spp., Low-Density Polyethylene (LDPE) Plastic Degrading Bacteria in Al-Ahsa Region, Saudi Arabia
Authors: Alamer Narjes J. , Aldayel Munirah F. , Khalifa Ashraf
Published: April 2023

Plastic pollution is one of the most serious environmental issues, causing severe environmental damage. It is of vital importance to find an efficient and eco-friendly approach to biodegrading plastics. The aim of this study was to isolate and characterize different bacterial isolates from water samples in the Al-Ahsa region of Saudi Arabia. The ability to degrade low-density polyethylene (LDPE) plastic was evaluated using multiple approaches, including changes in the media pH values, weight loss, Fourier transform infrared (FTIR), and gas chromatography–mass spectrometry (GC–MS). The water samples were collected from plastic-contaminated sites in Al-Ahsa, and bacterial isolates were obtained using a mineral nutrient medium (MNM) enriched with LDPE as the only carbon and energy source. Two bacterial isolates (APCK5 and APCZ14) were obtained and they showed potential LDPE degradation, as evidenced by changes in media pH (from 7.0 ± 0.03 to 6.17 ± 0.05 and 6.22 ± 0.03), LDPE weight reduction (8.1 ± 0.63% and 18.85 ± 0.96%, respectively), and FTIR and GC–MS analyses. Based on 16S rRNA gene similarities, APCZ14 and APCK5 were determined to be most closely related to the genus Brucella. APCZ14 exhibited a 99.48% homology with Brucella cytisi, whereas APCK5 showed a 99.33% similarity level to Brucella tritici. In conclusion, both bacterial strains had high efficiency in plastic biodegradation and could be developed for wide use as an eco-friendly method to remove or reduce plastic pollutants from the environment.
Classification Technique of Algae Using Hyperspectral Images of Algae Culture Media
Authors: Kim Gwang Soo , Gwon Yeonghwa , Oh Eun Ji , Kim Dongsu , Kwon Jae Hyun , Kim Young Do
Published: April 2023

Increases in algal growth have been reported in rivers, reservoirs, and other water resources worldwide, including Korea. Algal overgrowth can result in algal bloom, which has several negative impacts, such as ecosystem degradation and economic losses. Mitigation measures employed in Korea include an algal warning system and survey-based water quality forecast systems. However, these methods are time-consuming and require sample collection from the site. On the other hand, remote sensing techniques that use chlorophyll a are unable to distinguish between different types of algal species. In this paper, we aimed to identify a classification technique based on remote sensing methods that can be used to distinguish between blue-green algae and green algae. We acquired and prepared an algal culture solution and used a hyperspectral sensor to obtain an algae spectrum. Thereafter, we measured the absorption and emission spectra of blue-green and green algae and distinguished them using the instantaneous slope change of the spectrum. The absorption spectra for green algae showed two peaks at 417–437 nm and 661–673 nm, whereas those of blue-green algae showed three peaks at 449–529 nm, 433–437 nm, and 669–677 nm. The results of this study could form a basis for developing mitigation measures for algal overgrowth.
Approach Draft to Evaluate the Transport System State—A Case Study Regarding the Estimation Ratio Model of Transport Supply and Demand
Authors: Bartuska Ladislav , Stopka Ondrej , Luptak Vladimir , Masek Jaroslav
Published: April 2023

The article suggests a system dynamics model for estimating the demand for public transport. Traditional scientific and technical transport modeling approaches involve coherent systems, meticulously considering other impactful variables for transport modeling. The vastness of the variables and their combinations hinder us from grasping all possible system interactions. This research aims at proposing a model that comprises decisive factors in relation to the supply and demand in various modes of transport, designing likely scenarios of the transport system development in a specific transport territory. The model uses system dynamics tools to explore the interaction between individual system elements and transport subsystems. A wise choice of crucial system elements, well-adjusted relationships and behavior settings, as well as system dynamics tools, allow for a considerable simplification of an otherwise complex system. The article works with a principle of stock and flow diagrams for forecasting supply and demand in public transport. We take into consideration the implementation of a ‘demand index’ in public and car passenger transport with a subsequent comparison. This innovative approach monitors the development of a regional or municipal transport system while assessing its sustainability. Suggested demand indexes may serve as indicators for a sustainable municipal system. The suggested model reflects data from the South Bohemian region in the Czech Republic and may involve other elements and indicators of a sustainable transport system.
Dynamic Analysis and Seat Selection of Bus Driving Comfort under Different Road Conditions
Authors: Sun Rui , Wang Jianguo , Liu Ying
Published: April 2023

The comfort of a bus running on different road conditions is a matter of public concern. In this paper, the differential equations of motion are established for a bus running on different road conditions and the whole driving process is mechanically analyzed. Firstly, the bump degree at different positions is quantitatively analyzed and it is found that the rear row is bumpier on different roads. Then, the relationship between the speed of the bus and the vertical displacement and acceleration is quantitatively described. Regardless of the speed, a similar displacement and acceleration will be eventually achieved, but the speed is higher, and the duration of maximum displacement and acceleration is longer. When the speed is 8 m/s, resonance occurs on the bus during road condition II. Finally, the change in vertical displacement and acceleration under the action of different spring stiffness coefficient ratios of the front and rear wheels is quantitatively analyzed. High stiffness ratios mean less displacement and acceleration. By establishing an actual excitation road surface, the differential equations and analytical solutions in this paper can be used to roughly analyze the mechanical response of a traveling bus. These results can provide some guidance for the design and driving of buses.
Flavonoids as Promising Multitarget Agents in Alzheimer’s Disease Therapy
Authors: Lima Elisabete , Rauter Amélia , Medeiros Jorge
Published: April 2023

The increase in the occurrence of the multifactorial Alzheimer’s disease (AD) demands an urgent effort towards the development of effective anti-AD agents, such as the multitarget-directed ligands (MTDLs). In fact, AD is a genetic and an environmental disease, involving a diversity of etiopathogenic processes, and there is not yet a successful AD treatment. The major AD clinical indications (CIs) are extracellular amyloid plaques, intracellular neurofibrillary tangles (NFTs), abnormal inflammatory response, and neuron apoptosis and death caused by oxidative stress. The discovery of neuroprotective natural products, presenting good oral bioavailability, ability to cross the blood-brain barrier (BBB) and safety profile, is indeed a necessity, and some flavonoids are in clinical trials for AD treatment. In this review, the several flavonoids from natural sources that have shown activity on mechanisms associated with AD are presented. Although several reviews have been presented in the last few years, the main objective of this review is to recognize and discuss, for each CI, the scaffolds leading to the highest activity and so to attempt to achieve molecules targeting more than one CI, the MTDLs, which are potential leads for AD treatment. In conclusion, the most active flavonoids against several CIs of AD are flavanols and flavonols, which have a planar scaffold and structures presenting hydroxy groups at C5 and C7 on ring A and at C4′ of ring B. Thus, molecules linking flavanols to flavonols, with hydroxy groups at C5 and C7 on ring A and at C4′ of ring B, are also promising against CIs of AD and potential anti-AD agents.
Monitoring Pediatric Head CT Scan Dose Levels: A Retrospective Study of Diagnostic Reference Levels in a Single Hospital in Abu Dhabi, UAE
Authors: Abulail Ayman , Rahman Azhar Abdul , Noor Azman Nurul Zahirah , Hassan Jamal
Published: April 2023

Diagnostic reference levels (DRLs) are critical operational standards for monitoring radiological imaging parameters and ensuring patient safety in hospitals. A regular review of DRLs is necessary to optimize scanners and protocol parameters. This retrospective study collected data on the CT dose index volume and dose–length product for 250 children who underwent head CT scans in the region of Abu Dhabi, United Arab Emirates. Descriptive statistics were used to present median, range, and interquartile range values for each pediatric age group, based on region and protocol. The 75th percentile was used as the reference point for local DRLs. Proposed values of DRLs were suggested per age groups; 304 mGy∙cm (children < 1 year), 385 mGy∙cm (children ≥ 1 year to <5 years), 441 mGy∙cm (children ≥ 5 years to <10 years), and 568 mGy∙cm (patients ≥ 10 years to <16 years. A comparison of the local DRLs with previously established ones was carried out, and differences were discussed. To the best of our knowledge, this is the first study on pediatric head CT scans in this region. We believe the results can be used as a baseline for establishing local DRLs in the Emirate of Abu Dhabi and national DRLs in the United Arab Emirates.
Non-Parametric and Robust Sensitivity Analysis of the Weather Research and Forecast (WRF) Model in the Tropical Andes Region
Authors: Hinestroza-Ramirez Jhon E. , Rengifo-Castro Juan David , Quintero Olga Lucia , Yarce Botero Andrés , Rendon-Perez Angela Maria
Published: April 2023

With the aim of understanding the impact of air pollution on human health and ecosystems in the tropical Andes region (TAR), we aim to couple the Weather Research and Forecasting Model (WRF) with the chemical transport models (CTM) Long-Term Ozone Simulation and European Operational Smog (LOTOS–EUROS), at high and regional resolutions, with and without assimilation. The factors set for WRF, are based on the optimized estimates of climate and weather in cities and urban heat islands in the TAR region. It is well known in the weather research and forecasting field, that the uncertainty of non-linear models is a major issue, thus making a sensitivity analysis essential. Consequently, this paper seeks to quantify the performance of the WRF model in the presence of disturbances to the initial conditions (IC), for an arbitrary set of state-space variables (pressure and temperature), simulating a disruption in the inputs of the model. To this aim, we considered three distributions over the error term: a normal standard distribution, a normal distribution, and an exponential distribution. We analyze the sensitivity of the outputs of the WRF model by employing non-parametric and robust statistical techniques, such as kernel distribution estimates, rank tests, and bootstrap. The results show that the WRF model is sensitive in time, space, and vertical levels to changes in the IC. Finally, we demonstrate that the error distribution of the output differs from the error distribution induced over the input data, especially for Gaussian distributions.