bluuebunny/crossref_metadata_2025 huggingface dataset:
The reactivity of pyridine in cold interstellar environments: The reaction of pyridine with the CN radical
Authors: Heitkämper Juliane , Suchaneck Sarah , García de la Concepción Juan , Kästner Johannes , Molpeceres Germán
Published: December 2022

The recent detection of cyclic species in cold interstellar environments is an exciting discovery with yet many unknowns to be solved. Among them, the presence of aromatic heterocycles in space would act as an indirect evidence of the presence of precursors of nucleotides. The seeming absence of these species in the observations poses a fascinating conundrum that can be tackled with computational insights. Whilst many arguments can be given to explain the absence of heterocycles in space, one of the possible scenarios involves fast chemical conversion and formation of new species to be detected. We have tested this hypothesis for the reaction of pyridine with the CN radical to find possible scenarios in which the detectability of pyridine, as an archetypical heterocycle, could be enhanced or diminished via chemical conversions. Using a combination of ab-initio characterization of the reactive potential energy surface and kinetic and chemical simulations, we have established that pyridine does react very fast with CN radicals, estimating that the studied reactions is between 2.5–4.5 times faster in pyridine than in benzene, with a total loss rate constant of 1.33 × 10–9 cm3s−1 at 30 K, with an almost null temperature dependence in the (30–150) K range. Addition reactions forming 1,2,3-cyanopyridine are favored over abstraction reactions or the formation of isocyanides. Besides, for 1 and 2-cyanopyridine there is an increase in the total dipole moment with respect to pyridine, which can help in their detection. However, the reaction is not site specific, and equal amounts of 1,2,3-cyanopyridine are formed during the reaction, diluting the abundance of all the individual pyridine derivatives.
pyDARN: A Python software for visualizing SuperDARN radar data
Authors: Shi Xueling , Schmidt Marina , Martin Carley J. , Billett Daniel D. , Bland Emma , Tholley Francis H. , Frissell Nathaniel A. , Khanal Krishna , Coyle Shane , Chakraborty Shibaji , Detwiller Marci , Kunduri Bharat , McWilliams Kathryn
Published: December 2022

The Super Dual Auroral Radar Network (SuperDARN) is an international network of high frequency coherent scatter radars that are used for monitoring the electrodynamics of the Earth’s upper atmosphere at middle, high, and polar latitudes in both hemispheres. pyDARN is an open-source Python-based library developed specifically for visualizing SuperDARN radar data products. It provides various plotting functions of different types of SuperDARN data, including time series plot, range-time parameter plot, fields of view, full scan, and global convection map plots. In this paper, we review the different types of SuperDARN data products, pyDARN’s development history and goals, the current implementation of pyDARN, and various plotting and analysis functionalities. We also discuss applications of pyDARN, how it can be combined with other existing Python software for scientific analysis, challenges for pyDARN development and future plans. Examples showing how to read, visualize, and interpret different SuperDARN data products using pyDARN are provided as a Jupyter notebook.
How open data and interdisciplinary collaboration improve our understanding of space weather: A risk and resiliency perspective
Authors: Ledvina Vincent E. , Palmerio Erika , McGranaghan Ryan M. , Halford Alexa J. , Thayer Aidan , Brandt Laura , MacDonald Elizabeth A. , Bhaskar Ankush , Dong Chuanfei , Altintas Ilkay , Colliander James , Jin Meng , Jain Richa N. , Chatterjee Subhamoy , Shaikh Zubair , Frissell Nathaniel A. , Chen Thomas Y. , French Ryan J. , Isola Brianna , McIntosh Scott W. , Mason Emily I. , Riley Pete , Young Tim , Barkhouse Wayne , Kazachenko Maria D. , Snow Martin , Ozturk Dogacan S. , Claudepierre Seth G. , Di Mare Francesca , Witteman Andy , Kuzub Jeremy
Published: December 2022

Space weather refers to conditions around a star, like our Sun, and its interplanetary space that may affect space- and ground-based assets as well as human life. Space weather can manifest as many different phenomena, often simultaneously, and can create complex and sometimes dangerous conditions. The study of space weather is inherently trans-disciplinary, including subfields of solar, magnetospheric, ionospheric, and atmospheric research communities, but benefiting from collaborations with policymakers, industry, astrophysics, software engineering, and many more. Effective communication is required between scientists, the end-user community, and government organizations to ensure that we are prepared for any adverse space weather effects. With the rapid growth of the field in recent years, the upcoming Solar Cycle 25 maximum, and the evolution of research-ready technologies, we believe that space weather deserves a reexamination in terms of a “risk and resiliency” framework. By utilizing open data science, cross-disciplinary collaborations, information systems, and citizen science, we can forge stronger partnerships between science and industry and improve our readiness as a society to mitigate space weather impacts. The objective of this manuscript is to raise awareness of these concepts as we approach a solar maximum that coincides with an increasingly technology-dependent society, and introduce a unique way of approaching space weather through the lens of a risk and resiliency framework that can be used to further assess areas of improvement in the field.
Evaluation of water-user performance in smallholder irrigation schemes in KwaZulu-Natal Province, South Africa: A stochastic meta-frontier analysis
Authors: Phali Lerato , Mudhara Maxwell , Ferrer Stuart , Makombe Godswill
Published: December 2022

Smallholder Irrigation Schemes (SIS) are pivotal in sustaining livelihoods and creating employment in rural communities of South Africa. However, despite the revitalization and rehabilitation of SIS by the government, the performance of farmers is still below par. This study evaluates the performance of water-users across four SIS in KwaZulu-Natal Province (KZN). Technical Efficiency was used as a proxy for performance and the Stochastic Meta-Frontier Analysis method was employed to measure the overall efficiency across 306 households. The efficiency model results showed that governance index, psychological capital, land tenure security, credit access and gender affect water-users' technical efficiency. The study concludes that interventions should be geared toward strengthening institutions and the empowerment of farmers through relevant training and access to credit. Furthermore, adequacy of water and its availability in the schemes should be improved to ensure profitability and productivity of water.
A comprehensive review of small regulatory RNAs in Brucella spp.
Authors: King Kellie A. , Caudill Mitchell T. , Caswell Clayton C.
Published: December 2022

Brucella spp. are Gram-negative bacteria that naturally infect a variety of domesticated and wild animals, often resulting in abortions and sterility. Humans exposed to these animals or animal products can also develop debilitating, flu-like disease. The brucellae are intracellular pathogens that reside predominantly within immune cells, typically macrophages, where they replicate in a specialized compartment. This capacity of Brucella to survive and replicate within macrophages is essential to their ability to cause disease. In recent years, several groups have identified and characterized small regulatory RNAs (sRNAs) as critical factors in the control of Brucella physiology within macrophages and overall disease virulence. sRNAs are generally < 300 nucleotides in length, and these independent sRNA transcripts are encoded either next to (i.e., cis-encoded) or at a distant location to (i.e., trans-encoded) the genes that they regulate. Trans-encoded sRNAs interact with the mRNA transcripts through short stretches of imperfect base pairing that often require the RNA chaperone Hfq to facilitate sRNA-mRNA interaction. In many instances, these sRNA-mRNA interactions inhibit gene expression, usually by occluding the ribosome-binding site (RBS) and/or by decreasing the stability of the mRNA, leading to degradation of the transcript. A number of sRNAs have been predicted and authenticated in Brucella strains, and a variety of approaches, techniques, and means of validation have been employed in these efforts. Nonetheless, some important issues and considerations regarding the study of sRNA regulation in Brucella need to be addressed. For example, the lack of uniform sRNA nomenclature in Brucella has led to difficulty in comparisons of sRNAs across the different Brucella species, and there exist multiple names in the literature for what are functionally the same sRNA. Moreover, even though bona fide sRNAs have been discovered in Brucella, scant functional information is known about the regulatory activities of these sRNAs, or the extent to which these sRNAs are required for the intracellular life and/or host colonization by the brucellae. Therefore, this review summarizes the historical context of Hfq and sRNAs in Brucella; our current understanding of Brucella sRNAs; and some future perspectives and considerations for the field of sRNA biology in the brucellae.
Predicting cross-protection against foot-and-mouth disease virus strains by serology after vaccination
Authors: Gubbins Simon , Paton David J. , Dekker Aldo , Ludi Anna B. , Wilsden Ginette , Browning Clare F. J. , Eschbaumer Michael , Barnabei Jamie , Duque Hernando , Pauszek Lisa L. , King Donald P.
Published: December 2022

Serology is widely used to predict whether vaccinated individuals and populations will be protected against infectious diseases, including foot-and-mouth disease (FMD), which affects cloven-hoofed animals. Neutralising antibody titres to FMD challenge viruses correlate to protection against FMD, for vaccinated cattle that are infected with the same strain as in the vaccine (homologous protection). Similar relationships exist for cross-strain protection between different vaccine and challenge viruses, although much less data are available for these heterologous studies. Poor inter-laboratory reproducibility of the virus neutralisation test (VNT) also hampers comparisons between studies. Therefore, day-of-challenge sera (n = 180) were assembled from 13 previous FMD cross-protection experiments for serotypes O (n = 2), A (n = 10), and SAT 2 (n = 1). These were tested by VNT against the challenge viruses at the FMD FAO World Reference Laboratory (WRLFMD) and the titres were compared to challenge outcomes (protected or not). This dataset was combined with equivalent serology and protection data for 61 sera from four cross-protection experiments carried out at WRLFMD for serotypes O (n = 2), A (n = 1), and Asia 1 (n = 1). VNT results and protection outcomes were also analysed for a serotype O cross-protection experiment involving 39 cattle, where the sera were not available for retesting at WRLFMD. Three categories of association between heterologous neutralising antibody titre and heterologous protection were found (Group 1–3). The log10 reciprocal titres associated on average with 75% protection (with 95% credible limits) were: Group 1: 2.46 (2.11–2.97); Group 2: 1.67 (1.49–1.92); Group 3: 1.17 (1.06–1.30). Further cross-protection data are needed to understand the factors that underpin this variability and to develop more robust antibody thresholds. Establishing cut-off serological titres that can be used to score the adequacy of vaccine-induced immunity will facilitate the monitoring and thereby the performance of FMD vaccination in the field.
Social behaviour and transmission of lameness in a flock of ewes and lambs
Authors: Lewis Katharine E. , Price Emily , Croft Darren P. , Langford Joss , Ozella Laura , Cattuto Ciro , Green Laura E.
Published: December 2022

Introduction

Sheep have heterogenous social connections that influence transmission of some infectious diseases. Footrot is one of the top five globally important diseases of sheep, it is caused byDichelobacter nodosusand transmits between sheep when infectious feet contaminate surfaces, e.g., pasture. Surfaces remain infectious for a few minutes to a few days, depending on surface moisture levels. Susceptible sheep in close social contact with infectious sheep might be at risk of becoming infected because they are likely to step onto infectious footprints, particularly dams and lambs, as they cluster together.

Methods

High resolution proximity sensors were deployed on 40 ewes and their 54 lambs aged 5–27 days, in a flock with endemic footrot in Devon, UK for 13 days. Sheep locomotion was scored daily by using a 0–6 integer scale. Sheep were defined lame when their locomotion score (LS) was ≥2, and a case of lameness was defined as LS ≥2 for ≥2 days.

Results

Thirty-two sheep (19 ewes, 9 single, and 4 twin lambs) became lame during the study, while 14 (5 ewes, 5 single, and 4 twin lambs) were lame initially. These 46 sheep were from 29 family groups, 14 families had >1 lame sheep, and transmission from ewes to lambs was bidirectional. At least 15% of new cases of footrot were from within family transmission; the occurrence of lameness was higher in single than twin lambs. At least 4% of transmission was due to close contact across the flock. Most close contact occurred within families. Single and twin lambs spent 1.5 and 0.9 hours/day with their dams, respectively, and twin lambs spent 3.7 hours/day together. Non-family sheep spent only 0.03 hours/day in contact. Lame single lambs and ewes spent less time with non-family sheep, and lame twin lambs spent less time with family sheep.

Discussion

We conclude that most transmission of lameness is not attributable to close contact. However, in ewes with young lambs, some transmission occurs within families and is likely due to time spent in close contact, since single lambs spent more time with their dam than twin lambs and were more likely to become lame.
Molecular detection and analysis of beak and feather disease viruses in Iran
Authors: Dolatyabi Sara , Peighambari Seyed Mostafa , Razmyar Jamshid
Published: December 2022

The beak and feather disease virus (BFDV) is one of the few pathogens capable of causing extinction of psittacines. To determine the prevalence and the nature of BFDV mutation, this study investigated the presence of the BFDV among 1,095 individual birds of the 17 psittacine species in Iran followed by analyzing the DNA sequences of seven replication-associated protein (rep) and 10 capsid (cap) genomes of the virus. The BFDV was found to be the foremost pathogen among more than 12 psittacine species, and phylogenetic analysis showed that the BFDV GenBank-published sequences from Poland, Saudi Arabia, South Africa, Taiwan, and Thailand were most similar to those of this study. Evolutionary analysis concluded that arginine, leucine, and glycine were the amino acids frequently involved in the least-conserved substitution patterns of BFDV, and conversely, methionine, glutamine, and tryptophan were the amino acids that exhibited ultra-high conservation through the substitution patterns. The high substitution rate of arginine to lysine and glycine to serine also made greater contribution to the BFDV gene mutation. The relative synonymous codon usage between two genes revealed that the cap genome encoded proteins frequently used fewer codons, while the rep genome encoded proteins used more codons only at moderate frequency, explaining the broader divergence of the cap compared to the rep sequence. The data analysis also introduced a new variant of BFDV that exists in the rep and cap sequences of budgerigars. While the existence of more new variants was suspected, more solid evidence is required to substantiate this suspicion.
Case report: Absent fluorodeoxyglucose uptake in a dog with unexpected brain death
Authors: Koo Yoonhoi , Na Yejin , Yun Taesik , Chae Yeon , Lee Dohee , Kim Hakhyun , Yang Mhan-Pyo , Kang Byeong-Teck
Published: December 2022

A 5-year-old male Maltese dog was presented with generalized tonic seizures and hypermetria. Multiple nodular subcortical cerebellar enhancements and meningeal enhancement were observed on magnetic resonance imaging. Fluorodeoxyglucose-positron emission tomography/computed tomography was performed due to suspicion of neoplastic disease, and no fluorodeoxyglucose uptake was observed in the intracranial structures. In PET images of this dog, absent fluorodeoxyglucose uptake was identified in the brain indicating no cerebral metabolism, strongly suggested brain death. The dog had no spontaneous breathing and no brainstem reflexes for more than 24 h after the termination of anesthesia. Through these results, this dog was diagnosed with unexpected brain death, and it is presumed that the cause was anesthesia. We report herein a case of brain death in a dog diagnosed using fluorodeoxyglucose-positron emission tomography/computed tomography.
SARSNTdb database: Factors affecting SARS-CoV-2 sequence conservation
Authors: Orgera John , Kelley James J. , Bar Omri , Vaidhyanathan Sathyanarayanan , Grigoriev Andrey
Published: December 2022

SARSNTdb offers a curated, nucleotide-centric database for users of varying levels of SARS-CoV-2 knowledge. Its user-friendly interface enables querying coding regions and coordinate intervals to find out the various functional and selective constraints that act upon the corresponding nucleotides and amino acids. Users can easily obtain information about viral genes and proteins, functional domains, repeats, secondary structure formation, intragenomic interactions, and mutation prevalence. Currently, many databases are focused on the phylogeny and amino acid substitutions, mainly in the spike protein. We took a novel, more nucleotide-focused approach as RNA does more than just code for proteins and many insights can be gleaned from its study. For example, RNA-targeted drug therapies for SARS-CoV-2 are currently being developed and it is essential to understand the features only visible at that level. This database enables the user to identify regions that are more prone to forming secondary structures that drugs can target. SARSNTdb also provides illustrative mutation data from a subset of ~25,000 patient samples with a reliable read coverage across the whole genome (from different locations and time points in the pandemic. Finally, the database allows for comparing SARS-CoV-2 and SARS-CoV domains and sequences. SARSNTdb can serve the research community by being a curated repository for information that gives a jump start to analyze a mutation’s effect far beyond just determining synonymous/non-synonymous substitutions in protein sequences.
La evolución de la comunicación organizacional y su impacto en las nuevas estructuras empresariales
Authors: Pacheco-Rodríguez Miryam Gabriela , Alvarez-Avilés Edgar Alexander
Published: December 2022

Las entidades desde su creación hasta la actualidad han pasado por diversos procesos transformacionales con la finalidad de mejorar su estructura organizacional y orientarlas al éxito empresarial. La comunicación ha sido uno de los principales componentes afectados positivamente por estos procesos que iniciaron en la década de 1940 y que medio siglo después llevaron a esta herramienta a consolidarla como una pieza clave en la gestión institucional. A pesar de lo antes mencionado, la realidad es que actualmente la información vinculada a este tema es dispersa, vagamente abordada y en ocasiones es escasa, lo que dificulta realizar nuevos estudios en este campo, pues, no se conoce con claridad lo que ya fue analizado y lo que aún se debe indagar del tema. Por eso, esta investigación tiene el objetivo de recopilar y estructurar desde una perspectiva teórica la ruta que ha seguido la evolución de la comunicación en el campo organizacional y como incide en la realidad de las empresas modernas. Este estudio se llevó a cabo gracias a una exhaustiva investigación documental realizada entre los meses de febrero del 2020 y enero del 2022 en las bases de datos de Scielo, Dialnet y DSpace identificando un total de 83.474 trabajos independientemente de la época o área temática, haciendo uso de términos como “comunicación interna”, “comunicación empresarial”, “flujos de la comunicación”, entre otras palabras y de los cuales se tomaron los trabajos más relevantes que permitían mostrar de manera clara y precisa la evolución de la comunicación en las empresas.
Inserción laboral de personas con discapacidad: estudio de caso
Authors: Bermeo-Peñafiel Yajaira Mabel , Naranjo-Sánchez Bertha Alice
Published: December 2022

Las oportunidades laborales permiten que el ser humano se desarrolle de forma integral, más aún, en el caso de las personas con discapacidad, ya que ello, contribuye a reafirmar su autoestima y realización profesional. Acorde a la normativa ecuatoriana las empresas que cuenten con mínimo veinticinco (25) trabajadores están obligadas a contratar el 4% de personas con discapacidad. Este artículo tiene como objetivo identificar el nivel de inserción laboral de personas con discapacidad en la Universidad Politécnica Salesiana sede Guayaquil. Se realizó una revisión bibliométrica para conocer los países en los que se han publicado artículos en relación con el tema investigado. La investigación descriptiva de corte transversal usó como instrumentos la entrevista y un cuestionario en línea que permitió conocer aspectos relevantes de la inserción laboral de las personas con discapacidad, destacando entre ellos: el proceso aplicado, el análisis del puesto con los ajustes requeridos, la accesibilidad física a las instalaciones, así como la incorporación de tecnologías asistivas. En el presente artículo se obtuvo como resultado el 100% de cumplimiento de inserción laboral de personas con discapacidad, incluido los sustitutos. Se recomienda continuar con mejoras en la accesibilidad de las instalaciones para favorecer una real inclusión.
Frequency Domain Design Method of the Aeroengine Fuel Servo Constant Pressure Difference Control System with High Performance
Authors: Zhao Wenshuai , Wang Xi , Long Yifu , Zhou Zhenhua , Tian Linhang
Published: December 2022

The constant pressure difference regulating mechanism is widely used in aeroengine fuel servo metering systems, and it almost decides the metering precision. However, the design theory and design method of the available constant pressure difference regulating mechanism are unclear, and it is difficult to follow the high stability, high accuracy, and high robustness requirements of the modern aeroengine fuel servo metering system. In this paper, the design theory of the constant pressure difference regulating mechanism is revealed, and it indicates that it consists of two basic control units: a state feedback stabilization controller to ensure the asymptotic stability and disturbance rejection performance; and a servo and feed-forward compensator to ensure the asymptotic tracking ability. In addition, based on the frequency domain analysis method, the decisive influences about the control gains of the two control units on the dynamic performance and stability are analyzed. On this basis, a frequency domain design method of the two core control gains is proposed to complete the design task of the closed-loop system. The simulation results show that, under the adverse conditions of 1 MPa strong step disturbance of the inlet pressure and 50 mm2 strong step disturbance of the variable inlet flow area, the steady-state working range of the controlled pressure difference meets 0.92 ± 0.01 MPa, the steady-state error is not more than 1%, the regulation time is not more than 0.01 s, the dynamic overshoot is not more than 10%, and the designed phase margin is more than 70°.
Development of Engine Maintenance Technology with Mixed Reality-Taking Pratt & Whitney JT9D as an Example
Authors: Wu Wen-Chung , Hung Cheng-Chiao
Published: December 2022

The engine is the heart of the aircraft and deeply affects performance, flight safety, and airline management, which makes it a critical component requiring maintenance. With the advancement of technology, augmented reality (AR), virtual reality (VR), and mixed reality (MR) technologies have been introduced one after another. To increase maintenance skill ability, it is important to train for aviation maintenance. Therefore, the engine maintenance mixed reality (EMMR) system was developed through mixed reality technology in this study. There are three different scenarios have been developed in the EMMR system for making engine maintenance easy. In the first scenario, an exploded diagram of the disassembled engine with the main components has been made and an animation of the fuel flow has been demonstrated to introduce the basic structure of the engine. In the second scenario, interactive buttons and animations have been used to simulate the removal of the engine from the wing of an airplane so that the users can understand the process of disassembling the engine. In the third scenario, hybrid reality has been implemented to interact with the virtual objects, so that users could simulate the disassembly and replacement of the engine fan blades and get familiar with the whole process. Students have been introduced to and have been familiarized with the Microsoft HoloLens 2 and a survey has been conducted before and after using the developed technology to understand if the currently developed EMMR could help students to understand the process of each engine maintenance in the general classroom and make the learning more efficient at the same time.
An Application of Analytical Target Cascading for a Hierarchical Multidisciplinary System: The Preliminary Design of a Launch Vehicle Powered by Hybrid Rocket Motors
Authors: Wang Pengcheng , Xu Weile , Zhu Hao , Tian Hui , Cai Guobiao
Published: December 2022

Analytical target cascading (ATC) is a method for coordinating hierarchical system design optimization with a decomposition-based framework. Since a launch vehicle (LV) is usually powered by two or more stages of rocket motors, the overall design of the LV clearly has a hierarchical structure, including system level (conducted by the general design department) and subsystem level (conducted by the motor stage design department). In particular, the subsystem level contains stage-divided elements rather than discipline-divided elements. Therefore, ATC is inherently suitable for the overall design of the LV. This paper presents an ATC decomposition framework for LV design according to practical engineering. The feasibility of the multi-island genetic algorithm (MIGA) used in the ATC decomposition is verified by a mathematical programming test, in which non-linear programming with the quadratic Lagrangian (NLPQL) algorithm is set as a comparison. The multi-disciplinary analysis modules of a hybrid rocket motor (HRM) propelled LV, including propulsion, structure, aerodynamics and trajectory, are established. A hierarchical decomposition is proposed for this multi-level design with a multi-disciplinary model. The application and optimization results verify the feasibility of the ATC decomposition framework with MIGA in the preliminary design of the LV and the final orbit accuracy is better than that of the MDF method. In addition, the final design schemes also prove that HRMs can be considered as a feasible choice of propulsion system for a small payload at low earth orbit.
Mixed Ration Silage Containing Tanzania Grass and Babassu By-Products for Dairy Cows
Authors: Ferreira Daniele , Bandeira Danrley , Zanine Anderson , Parente Henrique , Parente Michelle , Santos Edson , Lima Anny Graycy , Pinho Ricardo , Oliveira Juliana , Santos Francisco Naysson , Sousa Francisca Claudia , Costa Renata , Castro Carlos Rodolfo , Dórea João Ricardo
Published: December 2022

The use of mixed ration silage (MRS) provides animals with a diet formulation that meets their nutritional requirements. This study aimed to evaluate the fermentative profile, losses, chemical composition and in vitro dry matter digestibility of mixed ration silages, including babassu by-products as a feed alternative for dairy cows. A completely randomized design was used, with four treatments and five replications, which were composed of TGS: Tanzania grass silage; MRSS: Tanzania grass silage with corn and soybean meal; MRSF: Tanzania grass silage with corn, soybean meal and babassu flour; and MRSC: Tanzania grass silage with corn, soybean meal and babassu cake. There was a significant difference between MRS and TGS (p < 0.05) in the variables’ pH, gas (GL) and effluent losses (EL), dry matter recovery (DMR), water-soluble carbohydrates (WSC), dry matter (DM), crude protein (CP) and total digestible nutrients (TDN). There was no statistical difference in buffer capacity (BC), acid detergent lignin, hemicellulose, ether extract (EE) and aerobic stability. However, for the variables’ ammonia nitrogen (NH3-N) and non-fibre carbohydrate (NFC) content, lower values were observed in the MRS (p < 0.001). The babassu by-products, cake and flour, can replace corn by up to 50% of the total ration silage with Tanzania grass, meeting the nutritional requirements of dairy cows.
Gut Microbiome Studies in Livestock: Achievements, Challenges, and Perspectives
Authors: Forcina Giovanni , Pérez-Pardal Lucía , Carvalheira Júlio , Beja-Pereira Albano
Published: December 2022

The variety and makeup of the gut microbiome are frequently regarded as the primary determinants of health and production performances in domestic animals. High-throughput DNA/RNA sequencing techniques (NGS) have recently gained popularity and permitted previously unheard-of advancements in the study of gut microbiota, particularly for determining the taxonomic composition of such complex communities. Here, we summarize the existing body of knowledge on livestock gut microbiome, discuss the state-of-the-art in sequencing techniques, and offer predictions for next research. We found that the enormous volumes of available data are biased toward a small number of globally distributed and carefully chosen varieties, while local breeds (or populations) are frequently overlooked despite their demonstrated resistance to harsh environmental circumstances. Furthermore, the bulk of this research has mostly focused on bacteria, whereas other microbial components such as protists, fungi, and viruses have received far less attention. The majority of these data were gathered utilizing traditional metabarcoding techniques that taxonomically identify the gut microbiota by analyzing small portions of their genome (less than 1000 base pairs). However, to extend the coverage of microbial genomes for a more precise and thorough characterization of microbial communities, a variety of increasingly practical and economical shotgun techniques are currently available.
Multi-Drug Resistant Staphylococcus aureus Carriage in Abattoir Workers in Busia, Kenya
Authors: Obanda Benear Apollo , Gibbons Cheryl L. , Fèvre Eric M. , Bebora Lilly , Gitao George , Ogara William , Wang Shu-Hua , Gebreyes Wondwossen , Ngetich Ronald , Blane Beth , Coll Francesc , Harrison Ewan M. , Kariuki Samuel , Peacock Sharon J. , Cook Elizabeth A. J.
Published: December 2022

Abattoir workers have been identified as high-risk for livestock-associated Staphylococcus aureus carriage. This study investigated S. aureus carriage in abattoir workers in Western Kenya. Nasal swabs were collected once from participants between February-November 2012. S. aureus was isolated using bacterial culture and antibiotic susceptibility testing performed using the VITEK 2 instrument and disc diffusion methods. Isolates underwent whole genome sequencing and Multi Locus Sequence Types were derived from these data. S. aureus (n = 126) was isolated from 118/737 (16.0%) participants. Carriage was higher in HIV-positive (24/89, 27.0%) than HIV–negative participants (94/648, 14.5%; p = 0.003). There were 23 sequence types (STs) identified, and half of the isolates were ST152 (34.1%) or ST8 (15.1%). Many isolates carried the Panton-Valentine leucocidin toxin gene (42.9%). Only three isolates were methicillin resistant S. aureus (MRSA) (3/126, 2.4%) and the prevalence of MRSA carriage was 0.4% (3/737). All MRSA were ST88. Isolates from HIV-positive participants (37.0%) were more frequently resistant to sulfamethoxazole/trimethoprim compared to isolates from HIV-negative participants (6.1%; p < 0.001). Similarly, trimethoprim resistance genes were more frequently detected in isolates from HIV-positive (81.5%) compared to HIV-negative participants (60.6%; p = 0.044). S. aureus in abattoir workers were representative of major sequence types in Africa, with a high proportion being toxigenic isolates. HIV-positive individuals were more frequently colonized by antimicrobial resistant S. aureus which may be explained by prophylactic antimicrobial use.
Polymicrobial Infections and Biofilms: Clinical Significance and Eradication Strategies
Authors: Anju V T , Busi Siddhardha , Imchen Madangchanok , Kumavath Ranjith , Mohan Mahima S. , Salim Simi Asma , Subhaswaraj Pattnaik , Dyavaiah Madhu
Published: December 2022

Biofilms are population of cells growing in a coordinated manner and exhibiting resistance towards hostile environments. The infections associated with biofilms are difficult to control owing to the chronicity of infections and the emergence of antibiotic resistance. Most microbial infections are contributed by polymicrobial or mixed species interactions, such as those observed in chronic wound infections, otitis media, dental caries, and cystic fibrosis. This review focuses on the polymicrobial interactions among bacterial-bacterial, bacterial-fungal, and fungal-fungal aggregations based on in vitro and in vivo models and different therapeutic interventions available for polymicrobial biofilms. Deciphering the mechanisms of polymicrobial interactions and microbial diversity in chronic infections is very helpful in anti-microbial research. Together, we have discussed the role of metagenomic approaches in studying polymicrobial biofilms. The outstanding progress made in polymicrobial research, especially the model systems and application of metagenomics for detecting, preventing, and controlling infections, are reviewed.
Epidemiology and Economic Outcomes Associated with Timely versus Delayed Receipt of Appropriate Antibiotic Therapy among US Patients Hospitalized for Native Septic Arthritis: A Retrospective Cohort Study
Authors: Balada-Llasat Joan-Miquel , Stamas Nicole , Vincent Tom , Timbrook Tristan T. , Saiontz-Martinez Cynthia , Hemmert Rachael B. , Berger Ariel
Published: December 2022

Timely administration of appropriate antibiotic therapy is associated with better patient outcomes and lower costs of care compared to delayed appropriate therapy, yet initial treatment is often empiric since causal pathogens are typically unknown upon presentation. The challenge for clinicians is balancing selection of adequate coverage treatment regimens, adherence to antimicrobial stewardship principles to deter resistance, and financial constraints. This retrospective cohort study aimed to assess the magnitude and impact of delayed appropriate antibiotic therapy among patients hospitalized with septic arthritis (SA) in the U.S. from 2017 to 2019 using healthcare encounter data. Timely appropriate therapy was defined as the receipt of antibiotic(s) with in vitro activity against identified pathogens within two days of admission; all other patients were assumed to have received delayed appropriate therapy. Of the 517 patients admitted to hospital for SA who met all selection criteria, 26 (5.0%) received delayed appropriate therapy. In inverse-probability-treatment-weighting-adjusted analyses, the receipt of delayed appropriate therapy was associated with an additional 1.1 days of antibiotic therapy, 1.4 days in length of stay, and $3531 in hospital costs (all vs. timely appropriate therapy; all p ≤ 0.02). Timely appropriate therapy was associated with a twofold increased likelihood of antibiotic de-escalation during the SA admission.
Effects of Coleus amboinicus L. Essential Oil and Ethanolic Extracts on Planktonic Cells and Biofilm Formation of Microsporum canis Isolated from Feline Dermatophytosis
Authors: Leesombun Arpron , Thanapakdeechaikul Karnchanarat , Suwannawiang Jiraporn , Mukto Pipada , Sungpradit Sivapong , Bangphoomi Norasuthi , Changbunjong Tanasak , Thongjuy Orathai , Weluwanarak Thekhawet , Boonmasawai Sookruetai
Published: December 2022

Microsporum canis is an important zoonotic fungus that causes dermatophytosis in domestic animals and their owners. Domestic cats are the primary reservoir for M. canis. Antifungal drugs frequently produce adverse effects on the host animal, increasing the demand for novel alternative treatments derived from nature. We evaluated the antifungal activity of Coleus amboinicus essential oil (CEO) and ethanolic extracts (CEE) against M. canis in planktonic and biofilm growth. Twelve clinical isolates of M. canis were identified in feline dermatophyte samples. Using GC-MS, 18 compounds were identified in CEO, with carvacrol being the major constituent. HPLC analysis of CEE revealed that it contained rosmarinic acid, apigenin, and caffeic acid. The planktonic growth of all M. canis isolates was inhibited by C. amboinicus extracts. The minimum inhibitory concentration at which ≥50% of the isolates were inhibited (MIC50) was 128 µg/mL (32–256 µg/mL) for both CEO and CEE. The MIC90 values of CEO and CEE were 128 and 256 µg/mL, respectively. CEO at MIC (128 µg/mL) and 2× MIC (256 µg/mL) significantly inhibited the biofilm formation of weak, moderate, and strong biofilm-producing M. canis. CEE at 2× MIC (256 µg/mL) significantly inhibited the biofilm formation of all isolates. Overall, C. amboinicus extracts inhibited planktonic growth and exhibited a significant antibiofilm effect against M. canis. Thus, C. amboinicus is a potential source of natural antifungal compounds.
Serum α-Carotene, but Not Other Antioxidants, Is Positively Associated with Muscle Strength in Older Adults: NHANES 2001–2002
Authors: Bruno Renata R. , Rosa Fernanda C. , Nahas Paula C. , de Branco Flávia M. S. , de Oliveira Erick P.
Published: December 2022

Aging is associated with an increased reactive oxygen species that can decrease muscle strength. Thus, antioxidant substances could be positively associated with muscle strength in older adults. To investigate the association between serum antioxidants and muscle strength in older adults. A cross-sectional study evaluating 1172 individuals (627 men and 545 women), aged 50 to 85 years from NHANES 2001–2002, was performed. Carotenoids (α-carotene, trans-β-carotene, cis-β-carotene, β-cryptoxanthin, lutein/zeaxanthin combination, trans-lycopene), vitamin E, and retinol were analyzed via the high-performance liquid chromatography method. Muscle strength was evaluated by the isokinetic knee extension test. Linear regression was performed to evaluate the association between tertiles of serum antioxidant levels and strength, adjusted for confounders (energy and protein intake, body mass index, sex, age, C-reactive protein, uric acid, race/ethnicity, marital status, annual household income, educational level, physical activity, smoking, hypertension, arthritis, and diabetes). Alpha-carotene levels (p-trend = 0.027) were positively associated with muscle strength. However, serum vitamin E, trans-β-carotene, cis-β-carotene, β-cryptoxanthin, carotenoids, and retinol levels were not associated with strength. Serum α-carotene, but not other antioxidants, was positively associated with muscle strength in older adults.
Signatures of Duschinsky Rotation in Femtosecond Coherence Spectra
Authors: Arpin Paul C. , Popa Mihail , Turner Daniel B.
Published: December 2022

The motions of nuclei in a molecule can be mathematically described by using normal modes of vibration, which form a complete orthonormal basis. Each normal mode describes oscillatory motion at a frequency determined by the momentum of the nuclei. Near equilibrium, it is common to apply the quantum harmonic-oscillator model, whose eigenfunctions intimately involve combinatorics. Each electronic state has distinct force constants; therefore, each normal-mode basis is distinct. Duschinsky proposed a linearized approximation to the transformation between the normal-mode bases of two electronic states using a rotation matrix. The rotation angles are typically obtained by using quantum-chemical computations or via gas-phase spectroscopy measurements. Quantifying the rotation angles in the condensed phase remains a challenge. Here, we apply a two-dimensional harmonic model that includes a Duschinsky rotation to condensed-phase femtosecond coherence spectra (FCS), which are created in transient–absorption spectroscopy measurements through impulsive excitation of coherent vibrational wavepackets. Using the 2D model, we simulate spectra to identify the signatures of Duschinsky rotation. The results suggest that peak multiplicities and asymmetries may be used to quantify the rotation angle, which is a key advance in condensed-phase molecular spectroscopy.
Research on Outdoor Thermal Comfort of Children’s Activity Space in High-Density Urban Residential Areas of Chongqing in Summer
Authors: Gu Han , Hu Qiqi , Zhu Dongsheng , Diao Jie , Liu Ying , Fang Mengmeng
Published: December 2022

Children’s activity spaces in communities designed for children’s recreation are related to children’s safety and physical health. Outdoor thermal comfort of children’s activity spaces in high-density urban residential areas is the key to children’s use in summer. To this end, meteorological measurements and questionnaires were conducted to better understand children’s outdoor thermal comfort in summer, and children’s outdoor thermal comfort was evaluated using the universal thermal climate index (UTCI) for children’s activity spaces in high-density residential areas of Chongqing, China. We draw four conclusions: (1) Different landscape types of children’s activity spaces have different effects on outdoor thermal comfort, and gender differences also affect outdoor thermal comfort in the same type of children’s activity space. (2) Global radiation (G) and air temperature (Ta) were the primary meteorological factors influencing children’s thermal sensations. (3) Outdoor thermal comfort of children’s activity spaces in high-density urban residential areas was inferior overall. (4) Neutral UTCI (NUTCI) for male and female children in Chongqing were 22.2 °C and 21.8 °C, NUTCI ranges (NUTCIR) were 18.4–26.1 °C (male) and 16.2–27.3 °C (female), and acceptable UTCI ranged from 23.2 to 39.1 °C (male) and 22.8 to 40.3 °C (female). The results provide guidance for landscape architects and urban planners in the Chongqing area to create comfortable outdoor spaces for children, improve their physical activity levels, and promote their physical and mental health.
Outdoor Microplastic Analysis Using Inlet Filters from an NOx Regulatory Air Quality Monitoring Device
Authors: Jenner Lauren C. , Kureshi Rameez Raja , White David , Chapman Emma , Sadofsky Laura R. , Rotchell Jeanette M.
Published: December 2022

Atmospheric microplastics (MPs) are a ubiquitous environmental contaminant of emerging concern. Sampling methods provide information relating to surface area concentration and MP characteristics, without direct comparison with routinely measured standard air quality parameters. This study analysed 6 active air samples generated by a local authority as part of their routine air quality monitoring activities. Continuous sampling totalled 10 months, within the city centre of Kingston-upon-Hull. By using μFTIR analysis, levels of total particles detected using the NOx inlet filters ranged from 5139 ± 2843 particles m−2 day−1, comprising 1029 ± 594 MPs m−2 day−1. The controls displayed a mean level of 2.00 ± 3.49 MPs. The polymers nylon (32%) and polypropylene, PP (22%) were the most abundant. Small fragments of 47.42 ± 48.57 μm (length) and 21.75 ± 13.62 μm (width) were most common. An increase in MP levels during April 2020 coincided with an increase in PM10 levels. This study used robust procedures to measure MPs in the air by exploiting existing air quality monitoring equipment. Knowing the levels, types, and characteristics of MPs can inform toxicity studies to provide more environmentally relevant exposures, which is urgent now that MPs have been reported in human lung tissue.
Chitosan-Carboxymethylcellulose Hydrogels as Electrolytes for Zinc–Air Batteries: An Approach to the Transition towards Renewable Energy Storage Devices
Authors: Bósquez-Cáceres María Fernanda , Lima Lola De , Morera Córdova Vivian , Delgado Anabel D. , Béjar José , Arjona Noé , Álvarez-Contreras Lorena , Tafur Juan P.
Published: December 2022

Biopolymers are promising materials as electrolytes with high flexibility, good performance, cost effectiveness, high compatibility with solvents, and film-forming ability. Chitosan (CS) and carboxymethylcellulose (CMC) can form an intermolecular complex, giving rise to hydrogels capable of absorbing ionic solutions. Citric acid (CA) is an effective biological chemical crosslinker that assists the formation of amide and ester bonds between CMC and CS, resulting in a structure with high ionic conductivity and good structural integrity. In this study, a chemical crosslinking strategy is used to synthesize electrolyte hydrogels for zinc–air batteries. The effects of crosslinking are studied on the structural and electrochemical performance of the membranes. The results show an improvement in the ionic conductivity with respect to the homologous electrolyte hydrogel systems reported, with a maximum of 0.19 S∙cm−1 at 30 °C. In addition, the cyclic voltammetry studies showed a current intensity increase at higher CA content, reaching values of 360 mA∙cm−2. Structural characterization suggests a higher thermal stability and a decrease in the degree of crystallinity caused by the polymers’ crosslinking. Finally, these membranes were tested in Zn–air batteries, obtaining power densities of 85 mW∙cm−2. The proposed hydrogels show to be appropriate for energy zinc–air battery applications and present an alternative to support the sustainable energy transition.
Biofilm Formation of Probiotic Saccharomyces cerevisiae var. boulardii on Glass Surface during Beer Bottle Ageing
Authors: Mohammadi Khosrow , Saris Per Erik Joakim
Published: December 2022

While brewing probiotic beer using Saccharomyces cerevisiae var. boulardii, we noticed the yeast potentially makes biofilm in glass bottles as the bottles get hazy. In this study, S. cerevisiae var. boulardii CNCM I-745 was used as a starter culture to produce probiotic beer. We studied the biofilm parameters combined with FLO11 mRNA expression and used light and scanning electron microscopy to document biofilm formation and structure. Our results revealed that ageing the beer and maturing from a sugar-rich to a sugar-limited beer, along with the stress factors from the brewing process (pH reduction and produced metabolites), led to an increase in biofilm mass; however, the viable count remained relatively stable (approximately 7.1 log10 cells/mL). Biofilm S. boulardii cells showed significantly higher FLO11 mRNA expression in the exponential and stationary phase compared to the planktonic cells. This study, therefore, provides evidence that S. cerevisiae var. boulardii makes biofilm on glass surfaces during beer bottle ageing. The impact of complications caused by formed biofilms on returnable bottles emphasizes the significance of this study.