bluuebunny/crossref_metadata_2025 huggingface dataset:
Nowcasting unemployment rate during the COVID-19 pandemic using Twitter data: The case of South Africa
Authors: Nia Zahra Movahedi , Asgary Ali , Bragazzi Nicola , Mellado Bruce , Orbinski James , Wu Jianhong , Kong Jude
Published: December 2022

The global economy has been hard hit by the COVID-19 pandemic. Many countries are experiencing a severe and destructive recession. A significant number of firms and businesses have gone bankrupt or been scaled down, and many individuals have lost their jobs. The main goal of this study is to support policy- and decision-makers with additional and real-time information about the labor market flow using Twitter data. We leverage the data to trace and nowcast the unemployment rate of South Africa during the COVID-19 pandemic. First, we create a dataset of unemployment-related tweets using certain keywords. Principal Component Regression (PCR) is then applied to nowcast the unemployment rate using the gathered tweets and their sentiment scores. Numerical results indicate that the volume of the tweets has a positive correlation, and the sentiments of the tweets have a negative correlation with the unemployment rate during and before the COVID-19 pandemic. Moreover, the now-casted unemployment rate using PCR has an outstanding evaluation result with a low Root Mean Square Error (RMSE), Mean Absolute Percentage Error (MAPE), Symmetric MAPE (SMAPE) of 0.921, 0.018, 0.018, respectively and a high R2-score of 0.929.
Open access and its potential impact on public health – A South African perspective
Authors: Strydom Adéle , Mellet Juanita , Van Rensburg Jeanne , Viljoen Ignatius , Athanasiadis Anastasios , Pepper Michael S.
Published: December 2022

Traditionally, access to research information has been restricted through journal subscriptions. This means that research entities and individuals who were unable to afford subscription costs did not have access to journal articles. There has however been a progressive shift toward electronic access to journal publications and subsequently growth in the number of journals available globally. In the context of electronic journals, both open access and restricted access options exist. While the latter option is comparable to traditional, subscription-based paper journals, open access journal publications follow an “open science” publishing model allowing scholarly communications and outputs to be publicly available online at no cost to the reader. However, for readers to enjoy open access, publication costs are shifted elsewhere, typically onto academic institutions and authors. SARS-CoV-2, and the resulting COVID-19 pandemic have highlighted the benefits of open science through accelerated research and unprecedented levels of collaboration and data sharing. South Africa is one of the leading open access countries on the African continent. This paper focuses on open access in the South African higher education research context with an emphasis on our Institution and our own experiences. It also addresses the financial implications of open access and provides possible solutions for reducing the cost of publication for researchers and their institutions. Privacy in open access and the role of the Protection of Personal Information Act (POPIA) in medical research and secondary use of data in South Africa will also be discussed.
Comparative assessment of road traffic noise through 2D noise mapping: A case study of an urban area
Authors: Alam Pervez , Mazhar Mohd. Aamir , Ahmad Kafeel , Aslam Zishan , Afsar S. S. , Husain Atif
Published: December 2022

Noise pollution has risen to a worrying degree in all zones of the city (residential, commercial, industrial, and silent) because of the rapid rise in urbanization, industrialization, and other connectivity of transport systems in all zones of the city. It has always been challenging to identify noise hotspots where immediate remedial measures are required. In addition to providing the propagation of noise in the X and Z direction, 2D noise mapping is an essential method for identifying regions where noise levels may reach a hazardous level. Thus, the comparative examination of all residential areas inside a city provides a clear picture of noise exposure. The main focus of this study is to carry out comparative analysis of noise exposure level of selected locations such as residential commercial, industrial and silent area of Delhi city using 2D noise maps. For noise monitoring, Sound Level Meter (SLM) Larson & Davis 831 in compliance with the standard procedure of CPCB is used for monitoring peak traffic hours of working day and night. After that, using sound PLAN (acoustic) and MapInfo Pro, 2-D (Desktop GIS) noise maps were developed, visualized, and analyzed. According to the findings, residential areas have been recorded as having the highest levels of noise, followed by commercial and silent zones, and industrial areas have been seen to have the lowest levels of noise. The high noise level in residential area may be due to heavy traffic volume and road surrounded by high rise buildings. Whereas minimum noise has been observed in industrial area because the industries along the major roads have been surrounded with parapets and trees. As a result, only a small amount of industrial noise entered major highways/roads. Additionally, 2D noise map revealed that the surrounding structures of road (high rise buildings, brick walls, grilled boundaries, trees etc.) significantly influence propagation of noise in all directions. These maps may also be utilized by decision makers in the process of formulating noise control strategies or implementing corrective measures.
Ecocritical analysis of “glocal” essays on Lived Experiences of Climate Change in higher education
Authors: van Herten Marjolein , Perez Paquita
Published: December 2022

As a “super-wicked problem,” climate change deserves a multidisciplinary approach in higher education that actively engages students with this global issue that has both local and regional consequences. The online short learning program “Climate change: from global to local action” combines environmental scientific, economic, and social knowledge. The conceptual model of Lived Experience of Climate Change (LivExpCC) aims at engaging students with climate change and explicitly adds the human dimension. Students write an essay using the LivExpCC-model: they connect their personal and local experiences with regional proximate influences and with broader global contextual influences of climate change. This stimulates the knowledge–reflection–engagement–action cycle. We analyze student essays from an environmental humanities perspective, looking specifically at distances (spatial and temporal distances and distances in interest). The results of these ecocritical analyses show that limited local distances and vivid inherited histories reflect the awareness of students of the effects of climate change and how they engage with it in different ways.
Consolidation of the Gaia catalogue with Chinese Space Station Telescope astrometry
Authors: Gai M. , Vecchiato A. , Busonero D. , Riva A. , Cancelliere R. , Lattanzi M. , Qi Z.
Published: December 2022

The issue of preservation and improvement of the Gaia catalogue throughout the next few decades is addressed. The goal of this study is to evaluate the feasibility of astrometric parameter update, for objects already in the catalogue, by inclusion of new observations from other space missions, in particular CSST. The proposed approach consists in modeling the astrometric fit of sources in the extragalactic region of the Gaia sample with new observations, using the stars in the local field as reference for each target. The concept is verified by simulation, in the framework of the expectations on the Gaia astrometric performance and on the data from the forthcoming CSST Optical Survey. This approach can mitigate the natural degradation of the initial precision on coordinates of Gaia sources with time by improving proper motions by a factor >3, thus improving the positional precision in future epochs. Moreover, the catalogue is densified by the inclusion of objects below the Gaia limiting magnitude, improving on the galactic population census and on extragalactic population. CSST-OS data will reduce the Gaia precision degradation on positions by a factor of 2.7 over 30 years and increase the number of available reference sources over 40% of the sky. Future observations from other missions may further improve on the Gaia catalogue by extending the sky coverage and temporal baseline.
Observing the signatures of AGB s-process nucleosynthesis in planetary nebulae: An origins story
Authors: Dinerstein Harriet L.
Published: December 2022

I relate an anecdotal history of the beginnings of a new initiative in studies of the chemical composition of planetary nebulae: namely, investigating abundances of elements beyond the iron-peak through infrared spectroscopy. In some planetary nebulae many of these elements display enrichments due to neutron capture reactions within the progenitor stars. This snippet of history provides an example of how science advances from the convergence of improvements in instrumentation, cross-over between fields, and constructive interaction between theory and observation. It also highlights the fact that terra incognita and discovery space remains even in seemingly well-established fields of science.
Investigating risk factors behind piglet facial and sow teat lesions through a literature review and a survey on teeth reduction
Authors: Chou Jen-Yun , Marchant Jeremy N. , Nalon Elena , Huynh Thuy T. T. , van de Weerd Heleen A. , Boyle Laura A. , Ison Sarah H.
Published: December 2022

Introduction:

Piglet facial and sow teat lesions are the main reported reasons why pig producers routinely practice teeth resection. This is a painful procedure performed on piglets, where their needle teeth are clipped or ground to resect the pointed tip. The practice raises welfare concerns. In contrast to other procedures, such as tail docking, we know little about the risk factors for these two types of lesions.

Methods

We employed two methods to answer these questions: (1) reviewing the literature to identify potential risk factors, and (2) surveying pig production stakeholders worldwide to identify the occurrence of these lesions and the strategies used in practice that enable pig producers to manage or prevent these lesions while avoiding teeth resection. For the literature review, we used Google Scholar to include peer-reviewed publications and gray literature. We distributed the survey using convenience sampling and documented information on the current situation regarding teeth resection, including the methods, frequencies, and reasons for resecting piglets' teeth, the occurrence of piglet facial and sow teat lesions, and measures used to prevent and control these lesions.

Results

The literature review identified six major risk factors for both lesions, including the presence or absence of teeth resection, housing system, litter size, piglet management, environmental enrichment, milk production and other piglet management practices. However, most studies focused on the effects of the first two factors with very few studies investigating the other risk factors. There were 75 responses to the survey from 17 countries. The survey showed that half of the respondents practiced teeth resection with many recognizing that facial and teat lesions are the main reasons behind this practice. However, many producers used other interventions rather than teeth resection to prevent these lesions. These interventions focused on improving milk production of the sow, managing large litters, and providing environmental enrichment.

Discussion

More research is needed to validate these interventions and more science-based advice is needed to bridge the gap between research and practice to help more producers further understand the cause of piglet facial and sow teat lesions to transition toward the cessation of routine teeth resection.
An Algorithmic Approach for the MIS Repair of Ventral Midline Hernias Associated With Diastasis of the Rectus Abdominis Muscle
Authors: Mandujano Cosman Camilo , Lima Diego L. , Xia Jason , Sreeramoju Prashanth , Malcher Flavio
Published: December 2022

Purpose: We present our algorithmic approach for symptomatic ventral hernias with Diastasis of the Rectus Abdominis Muscle (DRAM).

Methods: Retrospective analysis of patients with symptomatic ventral hernias and DRAM undergoing hernia repair and plication of DRAM from July 2018–March 2021 was conducted. Based on our algorithm, patients were selected for an Endoscopic Onlay Repair (ENDOR) or a Robotic Extended Totally Extraperitoneal Ventral Repair (R-eTEP).

Results: We performed a R-eTEP in fifty-seven patients and an ENDOR in twenty-four patients. In the R-eTEP group, thirty-seven (65%) patients were female, the mean age was 54.8 (±10.6), and the mean BMI was 32 (±4.8). Fifty patients (87.7%) had multiple defects, of which 19 (38%) were recurrent hernias and 31 (62%) were incisional hernias. The mean operative time was 200 (±62.4) minutes, with two cases requiring a hybrid approach. The median length of stay was 1 day (0–12), and the median follow-up was 103 days. Twenty-four patients underwent an ENDOR, 19 females (79.2%), the mean age was 45.7 years (±11.7) and the mean BMI was 28 (±3.6). 13 patients had isolated umbilical or epigastric hernias. The mean operative time was 146.2 min (±51.1). Fibrin sealant and suture was the predominant method for mesh fixation, and most cases were performed in an ambulatory setting. Four patients developed post-operative seromas; one requiring drainage due to infection. The Median follow-up was 48.5 days (10–523), with two reported hernia recurrences.

Conclusion: An algorithmic approach for adequate patient selection was shown to be safe for treating ventral hernias with DRAM.
Implementation and Control of a Wheeled Bipedal Robot Using a Fuzzy Logic Approach
Authors: Hsu Chun-Fei , Chen Bo-Rui , Lin Zi-Ling
Published: December 2022

This study designs and implements a wheeled bipedal robot (WBR) that combines the mobility of wheeled robots and the dexterity of legged robots. The designed WBR has extra knee joints to maintain body balance when encountering uneven terrain. Because of the robot’s highly nonlinear, dynamic, unstable, and under-actuated nature, an intelligent motion and balance controller (IMBC) based on a fuzzy logic approach is proposed to maintain the balance of the WBR while it is standing and moving on the ground. It should be emphasized that the proposed IMBC system does not require prior knowledge of system dynamics and the controller parameters are tuned using the qualitative aspects of human knowledge. Furthermore, a 32-bit microcontroller that has memory, programmable I/O peripherals, and a processor core is used to implement the IMBC method. Finally, moving and rotating, height-changing, posture-keeping, and “one leg on slope” movement scenarios are tested to demonstrate the feasibility of the proposed IMBC system. The experimental results show that, by using the proposed IMBC system, the WBR can not only balance and move well both on flat ground and in complex terrain but also extend each leg independently to maintain body balance.
Unsteady Numerical Investigation on the Sealing Effectiveness and Flow Field in Different Rim Seal Geometries
Authors: Zhang Qingcai , Wang Qinqin , Tan Xiaoming , Zhang Jingzhou
Published: December 2022

A rim seal is often used to prevent the ingress of high-temperature gas into the turbine disk cavity and protect the turbine disk from damage. Based on the overlapping rim seal (Seal-A), this paper proposes two more composite sealing structures (Seal-B and Seal-C) to show the effects of a deep cavity in the static disk and a modified platform in the rotating disk. Three-dimensional unsteady Reynolds-averaged Navier–Stokes equations and the shear stress transfer (SST) k-ω turbulence model were used to reveal the flow field characteristics and the sealing efficiency. The results show that the rotor–stator interaction plays a dominant role in the sealing outlet pressure, and the sealing efficiency in the outflow area obtained by the transient calculation is lower than that of the steady-state calculation. The rise in the cooling air flow enhances the reverse vortex in the sealing cavity, and the disk cavity’s sealing efficiency is also improved. When the cooling air flow ratio increases from 0.6% to 1.8%, the sealing efficiency at the high radius increases by 30%. The shape of the deep cavity produces a new return vortex at the lower part of the sealing cavity, which improves the sealing efficiency. The shark nose platform in Seal-C aggravates the gas ingress at the sealing outlet but improves the sealing efficiency at the sealing cavity. In general, compared with Seal-A, the sealing efficiency of Seal-B and Seal-C is increased by 13.5% and 10%, respectively, at a cooling air flow ratio of 0.6%.
Sensitivity Analysis of Geometrical Parameters to the Flow of Pre-swirl System after Turbine Blade Fracture
Authors: Zhao Gang , Qiu Tian , Liu Peng
Published: December 2022

The pre-swirl stator-rotor system is a common and important structure in gas turbines, and its main function is to provide cold air to the turbine blades with a low relative total temperature. Under normal conditions, the boundaries of the system are symmetrical and there is sufficient margin for each blade. However, a fracture of turbine blades can upset this balance, resulting in potentially different cold-air conditions for each blade. Therefore, to ensure the safety of the other blades after a single-blade break, it is necessary to know the cold-air distribution law of the system after a blade fracture. In this paper, the effects of geometric parameters (including pre-swirl angle, α; the area ratio of nozzles and holes, ξ; gap ratio, G; and radius ratio of nozzle and hole, δ) of a pre-swirl stator-rotor system on the mass-flow-rate ratio, η; total-pressure-loss coefficient, Cp; discharge coefficient of holes, Cd; and adiabatic effectiveness, Θad, are investigated by numerical simulation with a single blade fractured. The results show that most of the geometric parameter changes do not increase ηhole_0. Moreover, measures to increase the influence of pre-swirl nozzles can reduce the influence of blade fracture on mass flow distribution, such as larger α, smaller ξ, and smaller δ. As for Cp, Cd, and Θad, they are more sensitive to changes in α and ξ. For the pre-swirl system, to avoid more serious safety problems caused by individual blade fracture, the designer should make every effort to reduce the unevenness of the cold-air distribution. Increasing the effect of the nozzle could serve the aim, but it may increase the volatility of the flow. The pre-swirl nozzle of the leaf grille type is a good option to address flow fluctuations.
Large Eddy Simulation of Combustion for High-Speed Airbreathing Engines
Authors: Fureby Christer , Sahut Guillaume , Ercole Alessandro , Nilsson Thommie
Published: December 2022

Large Eddy Simulation (LES) has rapidly developed into a powerful computational methodology for fluid dynamic studies, between Reynolds-Averaged Navier–Stokes (RANS) and Direct Numerical Simulation (DNS) in both accuracy and cost. High-speed combustion applications, such as ramjets, scramjets, dual-mode ramjets, and rotating detonation engines, are promising propulsion systems, but also challenging to analyze and develop. In this paper, the building blocks needed to perform LES of high-speed combustion are reviewed. Modelling of the unresolved, subgrid terms in the filtered LES equations is highlighted. The main families of combustion models are presented, focusing on finite-rate chemistry models. The density-based finite volume method and the reaction mechanisms commonly employed in LES of high-speed H2-air combustion are briefly reviewed. Three high-speed combustor applications are presented: an experiment of supersonic flame stabilization behind a bluff body, a direct connect facility experiment as a transition case from ramjet to scramjet operation mode, and the STRATOFLY MR3 Small-Scale Flight Experiment. Several combinations of turbulence and combustion models are compared. Comparisons with experiments are also provided when available. Overall, the results show good agreement with experimental data (e.g., shock train, mixing, wall heat flux, transition from ramjet to scramjet operation mode).
The Shadow Values of Soil Hydrological Properties in the Production Potential of Climatic Regionalization of the Czech Republic
Authors: Slaboch Josef , Čechura Lukáš , Malý Michal , Mach Jiří
Published: December 2022

The Czech Republic uses a dual system of agricultural land prices, namely the formal/official price—for tax purposes—and the market price in the case of a standard sale or purchase of farmland. This paper focuses on the construction of an econometric model to quantify the influence of soil hydrological characteristics on the production potential in a given climatic region. It also focuses on the use of this model for the determination of the official price of agricultural land, which is expressed on the basis of the code of the evaluated soil-ecological unit (ESEU) and based on defined soil characteristics. The pricing itself is based on the production potential of the land, which in practice is very important for spatial planning, as it determines the classes of agricultural land protection with regard to the possibility of setting aside agricultural land for non-productive purposes or for drawing subsidies for less favourable areas. In this context, the non-productive functions of agricultural land are also frequently discussed, especially its retention, which plays a very important role in the currently changing climatic conditions. There are a number of studies on soil retention, and numerous approaches to measuring it, but none of them address its impact on production potential and thus on the price of land. For this reason, this paper focuses on defining the influence of the retention of the main soil units (defined for the conditions of the Czech Republic) on production potential. For this definition, SUR models are used, where the endogenous variable is expressed as production potential and the exogenous variables include the basic soil characteristics such as grain size, porosity, hydrological component of the soil, and retention. The obtained outputs show both the high explanatory power of the model and the adequate parametric significance of most variables, which provides sufficient support for the use of the results in practice. In addition, the estimated models across all climatic regions are consistent with substantively logical assumptions about the link between production potential and soil hydrological properties, which secondarily demonstrates their applicability in practice, especially for state administration, but also for local government in the sense of municipalities, cities, and other organizational units.
Different Floor Management Systems Affect Soil Properties and Initial Development of Apple Tree (Malus × domestica Borkh.) in an Orchard
Authors: Przybyłko Sebastian , Szpadzik Ewa , Marszał Jacek , Kowalczyk Wojciech , Wrona Dariusz
Published: December 2022

In order to achieve sustainable food production, non-chemical weed management practices need to be developed for fruit growing. Tailor-made floor management systems enable efficient weed regulation, but they also affect the soil quality in an orchard. In this article, the effects of various floor management systems in a ‘Red Jonaprince’ apple (Malus × domestica Borkh.) orchard on the soil properties and the trees’ nutritional status and initial development during the first two years after the orchard’s establishment were assessed. The experiment was set up in the spring of 2017 in the Experimental Orchard of WULS. ‘Red Jonaprince’ cv. trees grafted on M.9 rootstock were planted with 3.5 × 1 m spacing between them. Different floor management systems were applied to the rows, including the selected organic mulches: Miscanthus × giganteus straw (MG1 and MG2), spent mushroom substrates (SMS1 and SMS2), herbicide strip (HS), clear mechanical soil cultivation (MC), and synthetic black mulch (BC). The organic mulches affected the soil properties significantly. Spent mushroom substrates (SMS1, SMS2) increased the P and K contents in the soil, increased the salinity 10-fold, and retarded the growth in terms of the trunk cross-section area (TCSA) and its increment compared with other systems. Miscanthus × giganteus straw mulch (MG1, MG2) was associated with a more vigorous shoot growth compared with other combinations in the first year of the study as it provided a better tree nitrogen nutritional status. The floor management system affected the generative development of the trees. Mulching with a spent mushroom substrate boosted the flower bud formation intensity, but it did not affect the yielding quantity. Moreover, due to the poor fruit set, the trees mulched with a spent mushroom substrate (SMS2) gave a low initial bearing. High crop loads were noted for the trees treated with black synthetic mulch (BC) and the trees mulched with Miscanthus × giganteus straw (MG1). This was an effect of the tree size rather than the blooming intensity, while there were no differences in the cropping efficiency index (CEI) parameter.
Antifeeding, Toxic, and Growth-Reducing Activity of trans-Anethole and S-(+)-Carvone against Larvae of the Gypsy Moth Lymantria dispar (L.)
Authors: Kostić Igor , Milanović Slobodan , Kostić Miroslav , Šešlija Jovanović Darka , Ćalić Dušica , Jankovský Libor , Lazarević Jelica
Published: December 2022

Botanicals, such as essential oils (EO) and their compounds, are considered a viable eco-friendly alternative to synthetic insecticides, which threaten human health and ecosystem functioning. In the present study, we explored the potential use of two EO compounds, trans-anethole (phenylpropanoid) and S-(+)-carvone (monoterpene ketone), against gypsy moth larvae (GML), a serious pest of deciduous forests and orchards. GML feeding, survival, molting, and nutritional physiology were assessed at different compound concentrations and compared with the effects of the commercial botanical product NeemAzal®-T/S (neem). The impact of botanicals on GML feeding was assessed by the leaf-dipping method and showed the highest antifeeding activity of neem in the no-choice assay. GML that were offered a choice were deterred by anethole and attracted by low concentrations of carvone and neem. Ingestion of botanicals was more effective in inducing mortality and reducing molting than residual contact exposure. Anethole and carvone were better toxicants but worse growth regulators than neem. Assessing nutritional indices revealed reduced growth, consumption, and food utilization in larvae fed on botanical-supplemented diets. The highest metabolic cost of food processing was recorded in carvone-fed larvae, which exhibited a negative growth rate. The results suggest that anethole and carvone might be used as control agents against GML.
Using Internet Search Data to Forecast COVID-19 Trends: A Systematic Review
Authors: Ma Simin , Sun Yan , Yang Shihao
Published: December 2022

Since the outbreak of the coronavirus disease pandemic (COVID-19) at the end of 2019, many scientific groups have been working towards solutions to forecast outbreaks. Accurate forecasts of future waves could mitigate the devastating effects of the virus. They would allow healthcare organizations and governments to alter public intervention, allocate healthcare resources accordingly, and raise public awareness. Many forecasting models have been introduced, harnessing different underlying mechanisms and data sources. This paper provides a systematic review of forecasting models that utilize internet search information. The success of these forecasting models provides a strong support for the big-data insight of public online search behavior as an alternative signal to the traditional surveillance system and mechanistic compartmental models.
The Effect of Transportation on Puppy Welfare from Commercial Breeding Kennels to a Distributor
Authors: Romaniuk Aynsley C. , Diana Alessia , Barnard Shanis , Weller Jennifer E. , Espinosa Uri Baqueiro , Dangoudoubiyam Sriveny , Shreyer Traci , Arnott Gareth , Croney Candace
Published: December 2022

Many puppies from commercial breeding kennels (CBKs) are transported by ground from their kennels of origin to a distributor. This experience may elicit fear and stress during a sensitive developmental period, which may in turn negatively impact the puppies’ short- and long-term welfare. This study aimed to measure short-term effects of transportation on puppy welfare metrics. Eight-week-old puppies (n = 383) from 12 CBKs were tested at their kennels (pre-trans) and ~48 h after arriving at a distributor (post-trans). At each location, puppies underwent an isolation test, a stranger-approach test, and a physical health assessment. Behavioral responses to testing were scored from videos. Fecal glucocorticoid metabolites (FGM), fecal secretory immunoglobulin A (sIgA), and presence of intestinal parasites were also analyzed. Linear mixed-effects models identified decreased exploration (p < 0.001), and increased locomotion (p < 0.001) and escape attempts (p = 0.001) during the post-trans isolation test. Increased affiliative behavior (p < 0.001), FGM (p < 0.001) and sIgA (p = 0.014) were also observed post-trans. Findings support good physical health both pre- and post-trans, while behavioral and physiological changes suggest increased puppy distress post-trans. Higher post-transport affiliative behavior may indicate that puppies sought social support as a coping strategy after experiencing transport-related distress. Future studies should explore the efficacy of transportation-related interventions to mitigate puppy distress.
Population Pharmacokinetic Analysis Proves Superiority of Continuous Infusion in PK/PD Target Attainment with Oxacillin in Staphylococcal Infections
Authors: Murínová Irena , Švidrnoch Martin , Gucký Tomáš , Hlaváč Jan , Michálek Pavel , Slanař Ondřej , Šíma Martin
Published: December 2022

Considering its very short elimination half-life, the approved oxacillin dosage might not be sufficient to maintain the pharmacokinetic/pharmacodynamics (PK/PD) target of time-dependent antibiotics. This study aimed to describe the population pharmacokinetics of oxacillin and to explore the probability of PK/PD target attainment by using various dosing regimens with oxacillin in staphylococcal infections. Both total and unbound oxacillin plasma concentrations retrieved as a part of routine therapeutic drug-monitoring practice were analyzed using nonlinear mixed-effects modeling. Monte Carlo simulations were used to generate the theoretical distribution of unbound oxacillin plasma concentration–time profiles at various dosage regimens. Data from 24 patients treated with oxacillin for staphylococcal infection have been included into the analysis. The volume of distribution of oxacillin in the population was 11.2 L, while the elimination rate constant baseline of 0.73 h−1 increased by 0.3 h−1 with each 1 mL/s/1.73 m2 of the estimated glomerular filtration rate (eGFR). The median value of oxacillin binding to plasma proteins was 86%. The superiority of continuous infusion in achieving target PK/PD values was demonstrated and dosing according to eGFR was proposed. Daily oxacillin doses of 9.5 g, 11 g, or 12.5 g administered by continuous infusion have been shown to be optimal for achieving target PK/PD values in patients with moderate, mild, or normal renal function, respectively.
Cytotoxicity and Antibacterial Efficacy of AgCu and AgFe NanoAlloys: A Comparative Study
Authors: Zhou Fang , Kostantin Elie , Yang De-Quan , Sacher Edward
Published: December 2022

Although Ag nanoparticles (NPs) have been widely applied in daily life and in biomedical and industrial fields, there is a demand for Ag-based bimetallic nanoalloys (NAs), such as AgCu and AgFe, due to their enhanced antibacterial efficacy and reduced Ag consumption. In this work, we present a comparison study on the antibacterial efficacy and cytotoxicity rates of Ag NPs and AgCu and AgFe NAs to L929 mouse fibroblast cells using the CCK-8 technique based on the relative cell viability. The concept of the minimum death concentration (MDC) is introduced to estimate the cytotoxicity to the cells. It is found that the minimum inhibitory concentrations (MICs) of the NPs against E. coli and S. aureus decrease with the addition of both Cu and Fe. There is a strong correlation between the MDC and MIC, implying that the mechanisms of both antibacterial efficacy and cytotoxicity are similar. The enhanced antibacterial efficacy to bacteria and cytotoxicity toward the cell are attributed to Ag+ release. The following order is found for both the MIC and MDC: AgFe < AgCu < Ag NPs. However, there is no cytotoxicity to the L929 cells for AgFe and AgCu NAs at their MIC Ag concentrations against S. aureus.
Screening of Novel Antimicrobial Diastereomers of Azithromycin–Thiosemicarbazone Conjugates: A Combined LC-SPE/Cryo NMR, MS/MS and Molecular Modeling Approach
Authors: Habinovec Iva , Mikulandra Ivana , Pranjić Paula , Kazazić Saša , Paljetak Hana Čipčić , Barišić Antun , Bertoša Branimir , Bukvić Mirjana , Novak Predrag
Published: December 2022

A well-known class of antibacterials, 14- and 15-membered macrolides are widely prescribed to treat upper and lower respiratory tract infections. Azithromycin is a 15-membered macrolide antibiotic possessing a broad spectrum of antibacterial potency and favorable pharmacokinetics. Bacterial resistance to marketed antibiotics is growing rapidly and represents one of the major global hazards to human health. Today, there is a high need for discovery of new anti-infective agents to combat resistance. Recently discovered conjugates of azithromycin and thiosemicarbazones, the macrozones, represent one such class that exhibits promising activities against resistant pathogens. In this paper, we employed an approach which combined LC-SPE/cryo NMR, MS/MS and molecular modeling for rapid separation, identification and characterization of bioactive macrozones and their diastereomers. Multitrapping of the chromatographic peaks on SPE cartridges enabled sufficient sample quantities for structure elucidation and biological testing. Furthermore, two-dimensional NOESY NMR data and molecular dynamics simulations revealed stereogenic centers with inversion of chirality. Differences in biological activities among diastereomers were detected. These results should be considered in the process of designing new macrolide compounds with bioactivity. We have shown that this methodology can be used for a fast screening and identification of the macrolide reaction components, including stereoisomers, which can serve as a source of new antibacterials.
Physio-Biochemical and Transcriptomic Features of Arbuscular Mycorrhizal Fungi Relieving Cadmium Stress in Wheat
Authors: Li Hua , Wang Hongxia , Zhao Jianan , Zhang Lele , Li Yang , Wang Huijuan , Teng Huixin , Yuan Zuli , Yuan Zhiliang
Published: December 2022

Arbuscular mycorrhizal fungi (AMF) can improve plant cadmium (Cd) tolerance, but the tolerance mechanism in wheat is not fully understood. This study aimed to examine the physiological properties and transcriptome changes in wheat inoculated with or without Glomus mosseae (GM) under Cd stress (0, 5, and 10 mg·kg−1 CdCl2) to understand its role in wheat Cd tolerance. The results showed that the Cd content in shoots decreased while the Cd accumulation in roots increased under AMF symbiosis compared to the non-inoculation group and that AMF significantly promoted the growth of wheat seedlings and reduced Cd-induced oxidative damage. This alleviative effect of AMF on wheat under Cd stress was mainly attributed to the fact that AMF accelerated the ascorbate-glutathione (AsA-GSH) cycle, promoted the production of GSH and metallothionein (MTs), improved the degradation of methylglyoxal (MG), and induced GRSP (glomalin-related soil protein) secretion. Furthermore, a comparative analysis of the transcriptomes of the symbiotic group and the non-symbiotic group revealed multiple differentially expressed genes (DEGs) in the ‘metal ion transport’, ‘glutathione metabolism’, ‘cysteine and methionine metabolism’, and ‘plant hormone signal transduction’ terms. The expression changes of these DEGs were basically consistent with the changes in physio-biochemical characteristics. Overall, AMF alleviated Cd stress in wheat mainly by promoting immobilization and sequestration of Cd, reducing ROS production and accelerating their scavenging, in which the rapid metabolism of GSH may play an important role.
Unveiling the Vital Role of Long Non-Coding RNAs in Cardiac Oxidative Stress, Cell Death, and Fibrosis in Diabetic Cardiomyopathy
Authors: Tian Yuan , Gao Ziting , Liu Wenyun , Li Jinjie , Jiang Xin , Xin Ying
Published: December 2022

Diabetes mellitus is a burdensome public health problem. Diabetic cardiomyopathy (DCM) is a major cause of mortality and morbidity in diabetes patients. The pathogenesis of DCM is multifactorial and involves metabolic abnormalities, the accumulation of advanced glycation end products, myocardial cell death, oxidative stress, inflammation, microangiopathy, and cardiac fibrosis. Evidence suggests that various types of cardiomyocyte death act simultaneously as terminal pathways in DCM. Long non-coding RNAs (lncRNAs) are a class of RNA transcripts with lengths greater than 200 nucleotides and no apparent coding potential. Emerging studies have shown the critical role of lncRNAs in the pathogenesis of DCM, along with the development of molecular biology technologies. Therefore, we summarize specific lncRNAs that mainly regulate multiple modes of cardiomyopathy death, oxidative stress, and cardiac fibrosis and provide valuable insights into diagnostic and therapeutic biomarkers and strategies for DCM.
A Spatial Model for Repairing of the Dam Safety Monitoring Data Combining the Variable Importance for Projection (VIP) and Cokriging Methods
Authors: Li Shiwan , Li Yanling , Lu Xiang , Wu Zhenyu , Pei Liang , Liu Kexin
Published: December 2022

The safe operation of dams is related to the lifeline of the national economy, the safety of the people, and social stability, and dam safety monitoring plays an essential role in scientifically controlling the safety of dams. Since the effects of environmental variables were not considered in conventional monitoring data repairing methods (such as the single time series model and spatial interpolation model), a spatial model for repairing monitoring data combining the variable importance for projection (VIP) method and cokriging was put forward in this paper. In order to improve the accuracy of the model, the influence of different combinations of covariates on it was discussed, and the VIPj value greater than 0.8 was proposed as the threshold of covariates. The engineering verification shows that the VIP-cokriging spatial model had the advantages of high precision and strong applicability compared with the inverse distance weighting (IDW) model, the ordinary kriging model, and the universal kriging model, and the overall error can be reduced by more than 60%, which could better realize the expansion of the monitoring effect variable to the whole area of the dam space. The engineering application of the PBG dam showed that the model scientifically correlated the existing monitoring points with the spatial location of the dam, and reasonably repaired the measured values of the stopping and abnormal measured points, effectively ensuring that the spatial regular of the monitoring data could truly reflect the actual safety and operational status of the dam.
Special Issue on Challenges for Power Electronics Converters
Authors: Duan Jiandong , Wu Fengjiang , Liu Hongchen
Published: December 2022

Power electronics technology is playing an increasingly important role in modern energy utilization systems [...]
A Spore-Based Probiotic Containing Five Strains of Bacillus Had No Notable Effect on the Recovery of the Activity and Composition of the Baby Gut Microbiota Following Antibiotic Treatment in an In Vitro Model
Authors: Marzorati Massimo , Bubeck Sarah , Bayne Thomas , Krishnan Kiran , Giusto Morgan
Published: December 2022

Antibiotic use causes dysbiosis; probiotic treatment may mitigate these effects by promoting the growth of beneficial bacteria and restoring a healthy gut microbiota. The effects of a probiotic formulation (MegaSporeBiotic™; Bacillus indicus [HU36], Bacillus subtilis [HU58], Bacillus coagulans [SC208], Bacillus licheniformis [SL307], and Bacillus clausii [SC109]) on the microbial community activity and composition of the baby gut microbiome were evaluated using the in vitro gut model, the mucosal simulator of the human intestinal microbial system (M-SHIME®), and fecal samples from four babies aged 6–24 months. Established Baby-Quad-M-SHIME® proximal colon vessels (control period) were treated with 75 mg amoxicillin:clavulanic acid (2:1) for five days (antibiotic period) and then with/without daily MegaSporeBiotic™ (2 weeks; follow-up period). Antibiotic-induced dysbiosis was confirmed by significantly decreased SCFA levels and changes in the microbial community composition in the antibiotic vs. the control periods. SCFA levels recovered for both untreated and treated chambers during the follow-up period; recovery was similar among donors. There were few differences in microbial community composition between untreated and treated chambers during the follow-up period. MegaSporeBiotic™ supplementation following antibiotic-induced dysbiosis had little effect on the recovery of the microbial community activity or composition of the baby gut microbiota. Future studies evaluating simultaneous antibiotic and probiotic treatment may be of interest.
Comprehensive Investigations on Fluid Flow and Cavitation Characteristics in Rotating Disk System
Authors: Sun Junyu , Chen Liyu , Huang Hua , Zhang Bing , Qian Pengfei
Published: December 2022

The present work numerically investigates the flow behavior of Newtonian fluid between rotating disk systems. Rotating disk flow is an embranchment of fundamental flow research, which forms the theoretical basis for the flow media in many disk-type hydraulic machinery, and has been widely applied in energy, aerospace, vehicles, medical, and chemical areas. The Reynolds equation model of the rotating disk flow is established based on a series of assumptions, and considers the characteristics of hexahedral surface textures on the friction disk, and the control equation is dimensionless. The velocity, pressure, and pressure coefficient in oil film are solved by finite difference algorithm, and the shear cavitation incipient position is predicted. Graphical visualization and numerical data about cavitation characteristics are also presented. Furthermore, the cavitation process is researched in CFX and the experiment, eventually verifying the correctness of the numerical analysis. The pressure perturbation caused by texture boundaries and the low pressure at the vortex center induce the initial generation of cavitation, and cavitation effect can obviously enhance lubricating performance. The cavitation region extends from micro-dimples towards non-textured region when texture rate increases. This study can guide design of surface structures such as mechanical seals, wet clutches, and disk turbines.
Integration of Sentiment Analysis of Social Media in the Strategic Planning Process to Generate the Balanced Scorecard
Authors: Grande-Ramírez José Roberto , Roldán-Reyes Eduardo , Aguilar-Lasserre Alberto A. , Juárez-Martínez Ulises
Published: December 2022

Strategic planning (SP) requires attention and constant updating and is a crucial process for guaranteeing the efficient performance of companies. This article proposes a novel approach applied in a case study whereby a balanced scorecard (BSC) was generated that integrated sentiment analysis (SA) of social media (SM) and took advantage of the valuable knowledge of these sources. In this study, opinions were consolidated in the main dataset to incorporate sentiments regarding the strategic part of a restaurant in a tourist city. The proposed methodology began with the selection of the company. Information was then acquired to apply pre-processing, processing, evaluation, and validation that is capitalized in a BSC to support strategic decision-making. Python support was used in the model and comprised lexicon and machine learning approaches for the SA. The significant knowledge in the comments was automatically oriented toward the key performance indicators (KPIs) and perspectives of a BSC that were previously determined by a group of opinion leaders of the company. The methods, techniques, and algorithms of SA and SP showed that unstructured textual information can be processed and capitalized efficiently for optimal management and decision-making. The results revealed an improvement (reduced effort and time) to produce a more robust and comprehensive BSC with the support and validation of experts. Moreover, new resources and approaches were developed to implement more efficient SP. The model was based on the efficient coupling of both fields of study.
Light-YOLOv5: A Lightweight Algorithm for Improved YOLOv5 in Complex Fire Scenarios
Authors: Xu Hao , Li Bo , Zhong Fei
Published: December 2022

Fire-detection technology is of great importance for successful fire-prevention measures. Image-based fire detection is one effective method. At present, object-detection algorithms are deficient in performing detection speed and accuracy tasks when they are applied in complex fire scenarios. In this study, a lightweight fire-detection algorithm, Light-YOLOv5 (You Only Look Once version five), is presented. First, a separable vision transformer (SepViT) block is used to replace several Cross Stage Partial Bottleneck with 3 convolutions (C3) modules in the final layer of a backbone network to enhance both the contact of the backbone network to global information and the extraction of flame and smoke features; second, a light bidirectional feature pyramid network (Light-BiFPN) is designed to lighten the model while improving the feature extraction and balancing speed and accuracy features during a fire-detection procedure; third, a global attention mechanism (GAM) is fused into the network to cause the model to focus more on the global dimensional features and further improve the detection accuracy of the model; and finally, the Mish activation function and SIoU loss are utilized to simultaneously increase the convergence speed and enhance the accuracy. The experimental results show that compared to the original algorithm, the mean average accuracy (mAP) of Light-YOLOv5 increases by 3.3%, the number of parameters decreases by 27.1%, and the floating point operations (FLOPs) decrease by 19.1%. The detection speed reaches 91.1 FPS, which can detect targets in complex fire scenarios in real time.
Temporal-Guided Label Assignment for Video Object Detection
Authors: Tian Shu , Xia Meng , Yang Chun
Published: December 2022

In video object detection, the deterioration of an object’s appearance in a single frame brings challenges for recognition; therefore, it is natural to exploit temporal information to boost the robustness of video object detection. Existing methods usually utilize temporal information to enhance features, often ignoring the information in label assignments. Label assignment, which assigns labels to anchors for training, is an essential part of object detection. It is also challenged in video object detection and can be improved by temporal information. In this work, a temporal-guided label assignment framework is proposed for the learning task of a region proposal network (RPN). Specifically, we propose a feature instructing module (FIM) to establish the relation model among labels through feature similarity in the temporal dimension. The proposed video object detection framework was evaluated on the ImageNet VID benchmark. Without any additional inference cost, our work obtained a 0.8 mean average precision (mAP(%)) improvement over the baseline and achieved a mAP(%) of 82.0. The result was on par with the state-of-the-art accuracy without using any post-processing methods.