bluuebunny/crossref_metadata_2025 huggingface dataset:
PEGANs: Phased Evolutionary Generative Adversarial Networks with Self-Attention Module
Authors: Xue Yu , Tong Weinan , Neri Ferrante , Zhang Yixia
Published: August 2022

Generative adversarial networks have made remarkable achievements in generative tasks. However, instability and mode collapse are still frequent problems. We improve the framework of evolutionary generative adversarial networks (E-GANs), calling it phased evolutionary generative adversarial networks (PEGANs), and adopt a self-attention module to improve upon the disadvantages of convolutional operations. During the training process, the discriminator will play against multiple generators simultaneously, where each generator adopts a different objective function as a mutation operation. Every time after the specified number of training iterations, the generator individuals will be evaluated and the best performing generator offspring will be retained for the next round of evolution. Based on this, the generator can continuously adjust the training strategy during training, and the self-attention module also enables the model to obtain the modeling ability of long-range dependencies. Experiments on two datasets showed that PEGANs improve the training stability and are competitive in generating high-quality samples.
Some Statistical Aspects of the Truncated Multivariate Skew-t Distribution
Authors: Morán-Vásquez Raúl Alejandro , Zarrazola Edwin , Nagar Daya K.
Published: August 2022

The multivariate skew-t distribution plays an important role in statistics since it combines skewness with heavy tails, a very common feature in real-world data. A generalization of this distribution is the truncated multivariate skew-t distribution which contains the truncated multivariate t distribution and the truncated multivariate skew-normal distribution as special cases. In this article, we study several distributional properties of the truncated multivariate skew-t distribution involving affine transformations, marginalization, and conditioning. The generation of random samples from this distribution is described.
Multigrid Method for Solving Inverse Problems for Heat Equation
Authors: Al-Mahdawi Hassan K. Ibrahim , Abotaleb Mostafa , Alkattan Hussein , Tareq Al-Mahdawi Zena , Badr Amr , Kadi Ammar
Published: August 2022

In this paper, the inverse problems for the boundary value and initial value in a heat equation are posed and solved. It is well known that those problems are ill posed. The problems are reformulated as integral equations of the first kind by using the separation-of-variables method. The discretization of the integral equation allowed us to reduce the integral equation to a system of linear algebraic equations or a linear operator equation of the first kind on Hilbert spaces. The Landweber-type iterative method was used in order to find an approximation solution. The V-cycle multigrid method is used to obtain more frequent and fast convergence for iteration. The numerical computation examples are presented to verify the accuracy and fast computing of the approximation solution.
DL-Aided Underground Cavity Morphology Recognition Based on 3D GPR Data
Authors: Hou Feifei , Liu Xu , Fan Xinyu , Guo Ying
Published: August 2022

Cavity under urban roads has increasingly become a huge threat to traffic safety. This paper aims to study cavity morphology characteristics and proposes a deep learning (DL)-based morphology classification method using the 3D ground-penetrating radar (GPR) data. Fine-tuning technology in DL can be used in some cases with relatively few samples, but in the case of only one or very few samples, there will still be overfitting problems. To address this issue, a simple and general framework, few-shot learning (FSL), is first employed for the cavity classification tasks, based on which a classifier learns to identify new classes given only very few examples. We adopt a relation network (RelationNet) as the FSL framework, which consists of an embedding module and a relation module. Furthermore, the proposed method is simpler and faster because it does not require pre-training or fine-tuning. The experimental results are validated using the 3D GPR road modeling data obtained from the gprMax3D system. The proposed method is compared with other FSL networks such as ProtoNet, R2D2, and BaseLine relative to different benchmarks. The experimental results demonstrate that this method outperforms other prior approaches, and its average accuracy reaches 97.328% in a four-way five-shot problem using few support samples.
The Algorithm That Maximizes the Accuracy of k-Classification on the Set of Representatives of the k Equivalence Classes
Authors: Bernadotte Alexandra
Published: August 2022

The article formulates the Dictionary Recognition problem, which is relevant for a wide range of applied problems: word recognition in a noisy audio signal for natural language processing tasks or in a noisy electromagnetic signal, recognition of visual patterns in limited visibility, and much more. A Dictionary Recognition problem is finding a set of words from a given set to maximize the classification accuracy of the words in the dictionary without losing semantic representation. The idea of solving the problem is to represent a set of objects (encoded as a sequence of symbols or visual sequences) in the form of a k-partite graph, where each partite of the graph corresponds to a group of objects with a certain common feature (equivalence class). The task is to find such a set of representatives of the k equivalence classes on which the k-classification accuracy by the classifier H meets certain criteria: (1) maximum classification accuracy; (2) maximin accuracy—the binary classification accuracy of every two objects is not lower than a certain value. The proposed Maximin Algorithm provides k-partite cliques with a maximin worst-case classification accuracy and belongs to the P-class. The Maximal Algorithm provides k-partite cliques with the maximum total weight (the problem belongs to the NP-hard class). The presented algorithms select a set of representatives optimally in terms of classification accuracy for the certain classifier and runtime. The algorithms increase classification accuracy when using classical classification methods without additional optimization of the classifiers themselves. We tested the algorithms on simulated data and provide an open-source project on GitHub. The results of the Maximin and Maximal Algorithms give 4-, 8- and 16-classification accuracy close to the best accuracy (obtained by brute-force enumeration) and better than the median accuracy by more than 20% for the support vector machine classifiers. Furthermore, the algorithms increase the selection speed of representatives by five orders of magnitude compared to the brute-force algorithm with a slight loss of accuracy.
Study on Dynamic Characteristics of a Rotating Sandwich Porous Pre-Twist Blade with a Setting Angle Reinforced by Graphene Nanoplatelets
Authors: Peng Jiapei , Zhao Lefa , Zhao Tianyu
Published: August 2022

Lightweight blades with high strength are urgently needed in practical rotor engineering. Sandwich structures with porous core and reinforced surfaces are commonly applied to achieve these mechanical performances. Moreover, blades with large aspect ratios are established by the elastic plate models in theory. This paper studies the vibration of a rotating sandwich pre-twist plate with a setting angle reinforced by graphene nanoplatelets (GPLs). Its core is made of foam metal, and GPLs are added into the surface layers. Supposing that nanofillers are perfectly connected with matrix material, the effective mechanical parameters of the surface layers are calculated by the mixing law and the Halpin–Tsai model, while those of the core layers are determined by the open-cell scheme. The governing equation of the rotating plate is derived by employing the Hamilton principle. By comparing with the finite element method obtained by ANSYS, the present model and vibration analysis are verified. The material and structural parameters of the blade, including graphene nanoplatelet (GPL) weight faction, GPL distribution pattern, porosity coefficient, porosity distribution pattern, length-to-thickness ratio, length-to-width ratio, setting angle and pre-twist angle of the plate are discussed in detail. The finds provide important inspiration in the designing of a rotating sandwich blade.
Medical Diagnosis and Pattern Recognition Based on Generalized Dice Similarity Measures for Managing Intuitionistic Hesitant Fuzzy Information
Authors: Albaity Majed , Mahmood Tahir
Published: August 2022

Pattern recognition is the computerized identification of shapes, designs, and reliabilities in information. It has applications in information compression, machine learning, statistical information analysis, signal processing, image analysis, information retrieval, bioinformatics, and computer graphics. Similarly, a medical diagnosis is a procedure to illustrate or identify diseases or disorders, which would account for a person’s symptoms and signs. Moreover, to illustrate the relationship between any two pieces of intuitionistic hesitant fuzzy (IHF) information, the theory of generalized dice similarity (GDS) measures played an important and valuable role in the field of genuine life dilemmas. The main influence of GDS measures is that we can easily obtain a lot of measures by using different values of parameters, which is the main part of every measure, called DGS measures. The major influence of this theory is to utilize the well-known and valuable theory of dice similarity measures (DSMs) (four different types of DSMs) under the assumption of the IHF set (IHFS), because the IHFS covers the membership grade (MG) and non-membership grade (NMG) in the form of a finite subset of [0, 1], with the rule that the sum of the supremum of the duplet is limited to [0, 1]. Furthermore, we pioneered the main theory of generalized DSMs (GDSMs) computed based on IHFS, called the IHF dice similarity measure, IHF weighted dice similarity measure, IHF GDS measure, and IHF weighted GDS measure, and computed their special cases with the help of parameters. Additionally, to evaluate the proficiency and capability of pioneered measures, we analyzed two different types of applications based on constructed measures, called medical diagnosis and pattern recognition problems, to determine the supremacy and consistency of the presented approaches. Finally, based on practical application, we enhanced the worth of the evaluated measures with the help of a comparative analysis of proposed and existing measures.
Complex Noise-Resistant Zeroing Neural Network for Computing Complex Time-Dependent Lyapunov Equation
Authors: Liao Bolin , Hua Cheng , Cao Xinwei , Katsikis Vasilios N. , Li Shuai
Published: August 2022

Complex time-dependent Lyapunov equation (CTDLE), as an important means of stability analysis of control systems, has been extensively employed in mathematics and engineering application fields. Recursive neural networks (RNNs) have been reported as an effective method for solving CTDLE. In the previous work, zeroing neural networks (ZNNs) have been established to find the accurate solution of time-dependent Lyapunov equation (TDLE) in the noise-free conditions. However, noises are inevitable in the actual implementation process. In order to suppress the interference of various noises in practical applications, in this paper, a complex noise-resistant ZNN (CNRZNN) model is proposed and employed for the CTDLE solution. Additionally, the convergence and robustness of the CNRZNN model are analyzed and proved theoretically. For verification and comparison, three experiments and the existing noise-tolerant ZNN (NTZNN) model are introduced to investigate the effectiveness, convergence and robustness of the CNRZNN model. Compared with the NTZNN model, the CNRZNN model has more generality and stronger robustness. Specifically, the NTZNN model is a special form of the CNRZNN model, and the residual error of CNRZNN can converge rapidly and stably to order 10−5 when solving CTDLE under complex linear noises, which is much lower than order 10−1 of the NTZNN model. Analogously, under complex quadratic noises, the residual error of the CNRZNN model can converge to 2∥A∥F/ζ3 quickly and stably, while the residual error of the NTZNN model is divergent.
Non-Relativistic Treatment of the 2D Electron System Interacting via Varshni–Shukla Potential Using the Asymptotic Iteration Method
Authors: Edet Collins Okon , Mahmoud Salman , Inyang Etido P. , Ali Norshamsuri , Aljunid Syed Alwee , Endut Rosdisham , Ikot Akpan Ndem , Asjad Muhammad
Published: August 2022

The nonrelativistic treatment of the Varshni–Shukla potential (V–SP) in the presence of magnetic and Aharanov–Bohm fields is carried out using the asymptotic iteration method (AIM). The energy equation and wave function are derived analytically. The energy levels are summed to obtain the partition function, which is employed to derive the expressions for the thermomagnetic properties of the V–SP. These properties are analyzed extensively using graphical representations. It is observed that in the various settings of the analysis, the system shows a diamagnetic characteristic, and the specific heat capacity behavior agrees with the recognized Dulong–Petit law, although some slight anomaly is observed. This irregular behavior could be attributed to a Schottky anomaly. Our findings will be valuable in a variety of fields of physics, including chemical, molecular and condensed matter physics, where our derived models could be applied to study other diatomic molecules and quantum dots, respectively.
Infections in Burn Patients: A Retrospective View over Seven Years
Authors: Tsolakidis Savas , Freytag David Lysander , Dovern Elisabeth , Alharbi Ziyad , Kim Bong-Sung , Houschyar Khosrow Siamak , Reumuth Georg , Schäfer Benedikt , Rennekampff Hans-Oliver , Pallua Norbert , Grieb Gerrit
Published: August 2022

Backgroundand objectives: Burn patients represent a challenging cohort because the injuries entail a vulnerability to colonisation by microorganisms. The ensuing infections can lead to serious complications and, in many cases, to the death of the burn patient. Surgical intervention and wound dressings, as well as antibiotic treatment, are crucial for optimising the treatment of the patient. Materialand Methods: In this retrospective analysis, we analysed the treatment course, antibiotic therapy, and general complications of 252 burn patients with second- or third-degree burns over a time span of 7 years. Results: Patients who developed infections tended to have, on average, a higher total body surface area (TBSA), higher abbreviated burn severity index (ABSI) scores, and longer hospital stays. Patients who were admitted to the burn unit after 2006 had significantly shorter stays in the burn unit. TBSA and ABSI scores were lower in the patient cohort admitted after 2006. Patients exhibiting a TBSA greater than 30% had significantly longer hospital stays and antibiotic treatment periods. TBSA and ABSI scores were significantly higher in patients who died. The results of binary logistic regression indicate that a higher ABSI score increases the odds ratio of developing an infection. Bacteria number had no significant effect on the odds of patient death but positively influenced the odds ratio of developing an infection. TBSA was negatively associated with the risk of developing an infection and was an insignificant predictor of mortality. Conclusions: To gauge the optimal treatment for a burn patient, it is crucial for practitioners to correctly select, dose, and time antibiotics for the patient. Monitoring bacterial colonisation is vital to nip rising infection in the bud and ensure the correct antibiotic selection. This will help prevent the development of multi-resistant bacteria.
A Retrospective Narrative Mini-Review Regarding the Seminal Microbiota in Infertile Male
Authors: Doroftei Bogdan , Ilie Ovidiu-Dumitru , Dabuleanu Ana-Maria , Hutanu Delia , Vaduva Constantin-Cristian
Published: August 2022

Background: Infertility is a global burden that affects both sexes with the male component remaining as an explored yet crucial research field that might offer novel evidence. Material and Methods: The present narrative mini-review aims to summarize all existing literature regarding the composition of the seminal microflora in infertile men. We performed searches in PubMed/Medline, ISI Web of Knowledge, Scopus, and ScienceDirect between 2018 and 2022 using a combination of keywords. Results: A total of n = 33 studies met the eligibility criteria and were further considered. From this, n = 14 were conducted on human patients, n = 3 on zebrafish (Danio rerio), n = 5 on rats, and n = 11 on mice. In twenty-five out of thirty-three papers, the authors sequenced the 16S rRNA; situations occurred where researchers focused on standard laboratory protocols. Lactobacillus and Bifidobacterium are widely recognized as putative beneficial lactic bacteria. These two entities are capable of restoring the host’s eubiosis to some extent, blocking pathogens’ proliferation and endotoxins, and even alleviating specific patterns encountered in disease(s) (e.g., obesity, type 1 diabetes) due to prolonged exposure to toxicants in adults or from a developmental stage. Over the years, distinct approaches have been perfected, such as the transfer of feces between two species or conventional rudimentary products with proven efficiency. Conclusions: The seminal microflora is decisive and able to modulate psychological and physiological responses. Each individual possesses a personalized microbial profile further shaped by exogenous factors, regardless of sex and species.
A Global Survey on Diagnostic, Therapeutic and Preventive Strategies in Intensive Care Unit—Acquired Weakness
Authors: Klawitter Felix , Oppitz Marie-Christine , Goettel Nicolai , Berger Mette M. , Hodgson Carol , Weber-Carstens Steffen , Schaller Stefan J. , Ehler Johannes
Published: August 2022

Background and Objectives: Intensive care unit-acquired weakness (ICU-AW) is one of the most frequent neuromuscular complications in critically ill patients. We conducted a global survey to evaluate the current practices of diagnostics, treatment and prevention in patients with ICU-AW. Materials and Methods: A pre-survey was created with international experts. After revision, the final survey was endorsed by the European Society of Intensive Care Medicine (ESICM) using the online platform SurveyMonkey®. In 27 items, we addressed strategies of diagnostics, therapy and prevention. An invitation link was sent by email to all ESICM members. Furthermore, the survey was available on the ESICM homepage. Results: A total of 154 healthcare professionals from 39 countries participated in the survey. An ICU-AW screening protocol was used by 20% (28/140) of participants. Forty-four percent (62/141) of all participants reported performing routine screening for ICU-AW, using clinical examination as the method of choice (124/141, 87.9%). Almost 63% (84/134) of the participants reported using current treatment strategies for patients with ICU-AW. The use of treatment and prevention strategies differed between intensivists and non-intensivists regarding the reduction in sedatives (80.0% vs. 52.6%, p = 0.002), neuromuscular blocking agents (76.4% vs. 50%, p = 0.004), corticosteroids (69.1% vs. 37.2%, p < 0.001) and glycemic control regimes (50.9% vs. 23.1%, p = 0.002). Mobilization and physical activity are the most frequently reported treatment strategies for ICU-AW (111/134, 82.9%). The availability of physiotherapists (92/134, 68.7%) and the lack of knowledge about ICU-AW within the medical team (83/134, 61.9%) were the main obstacles to the implementation of the strategies. The necessity to develop guidelines for the screening, diagnosing, treatment and prevention of ICU-AW was recognized by 95% (127/133) of participants. Conclusions: A great heterogeneity regarding diagnostics, treatment and prevention of ICU-AW was reported internationally. Comprehensive guidelines with evidence-based recommendations for ICU-AW management are needed.
Microstructural Evolution and Stability of Coarse-Grained S31254 Super Austenitic Stainless Steel during Hot Deformation
Authors: Xing Jia , Liu Chengzhi , Li Aimin , Wang Shouming , Zhang Xinjie , Shi Yongxin
Published: August 2022

The ingot of S31254 super austenitic stainless steel (SASS) was annealed at 1220 °C for 70 h to eliminate the segregation of Mo element, and the grain size grows to the level of millimeter. The stress–strain response and microstructural evolution of coarse-grained S31254 SASS were investigated by hot compression tests in the temperature range of 950–1250 °C and strain rate range of 0.001–10 s−1. The results showed that the energy required for plastic deformation improved with the increase of strain rate and the decrease of deformation temperature. The hot deformation activation energy was calculated to be 542.91 kJ·mol−1 through the regression analysis of hyperbolic-sine function, and the constitutive equation was established. Processing maps were constructed, and two optimal hot working parameters ranges were clarified. Due to the low fraction of grain boundaries, the main deformation mechanism of coarse-grained S31254 SASS was dynamic recovery. However, when the deformation temperature improved to 1250 °C, recrystallized grains began to nucleate and grow along with the band-like structure within the austenitic grains. When the deformation temperature is 950–1150 °C, the microstructural stability of S31254 SASS under tension stress was excellent. However, when the temperature and the strain rate were 1250 °C and 0.5 s−1 respectively, the microstructural stability deteriorated resulting from the formation of δ-ferrite phase and local melting of austenitic grain boundaries.
O-GlcNAc Modification and Its Role in Diabetic Retinopathy
Authors: Liu Chengzhi , Dong Wenkang , Li Jun , Kong Ying , Ren Xiang
Published: August 2022

Diabetic retinopathy (DR) is a leading complication in type 1 and type 2 diabetes and has emerged as a significant health problem. Currently, there are no effective therapeutic strategies owing to its inconspicuous early lesions and complex pathological mechanisms. Therefore, the mechanism of molecular pathogenesis requires further elucidation to identify potential targets that can aid in the prevention of DR. As a type of protein translational modification, O-linked β-N-acetylglucosamine (O-GlcNAc) modification is involved in many diseases, and increasing evidence suggests that dysregulated O-GlcNAc modification is associated with DR. The present review discusses O-GlcNAc modification and its molecular mechanisms involved in DR. O-GlcNAc modification might represent a novel alternative therapeutic target for DR in the future.
Blood and Urinary Biomarkers of Antipsychotic-Induced Metabolic Syndrome
Authors: Khasanova Aiperi K. , Dobrodeeva Vera S. , Shnayder Natalia A. , Petrova Marina M. , Pronina Elena A. , Bochanova Elena N. , Lareva Natalia V. , Garganeeva Natalia P. , Smirnova Daria A. , Nasyrova Regina F.
Published: August 2022

Metabolic syndrome (MetS) is a clustering of at least three of the following five medical conditions: abdominal obesity, high blood pressure, high blood sugar, high serum triglycerides, and low serum high-density lipoprotein (HDL). Antipsychotic (AP)-induced MetS (AIMetS) is the most common adverse drug reaction (ADR) of psychiatric pharmacotherapy. Herein, we review the results of studies of blood (serum and plasma) and urinary biomarkers as predictors of AIMetS in patients with schizophrenia (Sch). We reviewed 1440 studies examining 38 blood and 19 urinary metabolic biomarkers, including urinary indicators involved in the development of AIMetS. Among the results, only positive associations were revealed. However, at present, it should be recognized that there is no consensus on the role of any particular urinary biomarker of AIMetS. Evaluation of urinary biomarkers of the development of MetS and AIMetS, as one of the most common concomitant pathological conditions in the treatment of patients with psychiatric disorders, may provide a key to the development of strategies for personalized prevention and treatment of the condition, which is considered a complication of AP therapy for Sch in clinical practice.
Longitudinally Extensive Transverse Myelitis Associated with Cytomegalovirus Infection in an Immunocompetent Patient
Authors: Montalvo Raul , Sánchez Vidal María-Fernanda
Published: August 2022

Longitudinally extensive transverse myelitis (LETM) associated with cytomegalovirus infection is extremely rare and is, mainly observed in immunocompetent people. A 55-year-old woman with no evidence of immunosuppression was admitted with paresthesia in the lower limbs for 15 days, difficulty walking, fecal incontinence, and acute urinary retention. Magnetic resonance imaging (MRI) in the T2 sequence showed signs of hyperintensity in the cervical and thoracic cord. The serological study showed IgM antibodies to cytomegalovirus, and the result of the FilmArray meningitis/encephalitis panel showed the presence of cytomegalovirus. She received treatment with methylprednisolone and ganciclovir with a favorable outcome. This case highlights the importance of investigating treatable causes in patients with longitudinally extensive transverse myelitis with acute presentation.
The Rare Actinobacterium Crossiella sp. Is a Potential Source of New Bioactive Compounds with Activity against Bacteria and Fungi
Authors: Gonzalez-Pimentel Jose Luis , Dominguez-Moñino Irene , Jurado Valme , Laiz Leonila , Caldeira Ana Teresa , Saiz-Jimenez Cesareo
Published: August 2022

Antimicrobial resistance has become a global problem in recent decades. A gradual reduction in drug discoveries has led to the current antimicrobial resistance crisis. Caves and other subsurface environments are underexplored thus far, and they represent indispensable ecological niches that could offer new molecules of interest to medicine and biotechnology. We explored Spanish show caves to test the bioactivity of the bacteria dwelling in the walls and ceilings, as well as airborne bacteria. We reported the isolation of two strains of the genus Crossiella, likely representing a new species, isolated from Altamira Cave, Spain. In vitro and in silico analyses showed the inhibition of pathogenic Gram-positive and Gram-negative bacteria, and fungi, as well as the taxonomical distance of both strains from their closest relative, Crossiella cryophila. The presence of an exclusive combination of gene clusters involved in the synthesis of lanthipeptides, lasso peptides, nonribosomal peptides and polyketides indicates that species of this genus could represent a source of new compounds. Overall, there is promising evidence for antimicrobial discovery in subterranean environments, which increases the possibility of identifying new bioactive molecules.
Detoxification Response of Pseudomonas fluorescens MFAF76a to Gaseous Pollutants NO2 and NO
Authors: Chautrand Thibault , Depayras Ségolène , Souak Djouhar , Bouteiller Mathilde , Kondakova Tatiana , Barreau Magalie , Ben Mlouka Mohamed Amine , Hardouin Julie , Konto-Ghiorghi Yoan , Chevalier Sylvie , Merieau Annabelle , Orange Nicole , Duclairoir-Poc Cécile
Published: August 2022

Bacteria are often exposed to nitrosative stress from their environment, from atmospheric pollution or from the defense mechanisms of other organisms. Reactive nitrogen species (RNS), which mediate nitrosative stress, are notably involved in the mammalian immune response through the production of nitric oxide (NO) by the inducible NO synthase iNOS. RNS are highly reactive and can alter various biomolecules such as lipids, proteins and DNA, making them toxic for biological organisms. Resistance to RNS is therefore important for the survival of bacteria in various environments, and notably to successfully infect their host. The fuel combustion processes used in industries and transports are responsible for the emission of important quantities of two major RNS, NO and the more toxic nitrogen dioxide (NO2). Human exposure to NO2 is notably linked to increases in lung infections. While the response of bacteria to NO in liquid medium is well-studied, few data are available on their exposure to gaseous NO and NO2. This study showed that NO2 is much more toxic than NO at similar concentrations for the airborne bacterial strain Pseudomonas fluorescens MFAF76a. The response to NO2 involves a wide array of effectors, while the response to NO seemingly focuses on the Hmp flavohemoprotein. Results showed that NO2 induces the production of other RNS, unlike NO, which could explain the differences between the effects of these two molecules.
Yellow Fever: Roles of Animal Models and Arthropod Vector Studies in Understanding Epidemic Emergence
Authors: Shinde Divya P. , Plante Jessica A. , Plante Kenneth S. , Weaver Scott C.
Published: August 2022

Yellow fever virus (YFV) is a mosquito-borne flavivirus circulating throughout the tropical and sub-tropical regions of Africa and South America. It is responsible for an estimated 30,000 deaths annually, and while there is a highly successful vaccine, coverage is incomplete, and there is no approved treatment for YFV infection. Despite advancements in the field, animal models for YFV infection remain scarce, and care must be taken to select an appropriate model for a given hypothesis. Small animal models require either adapted YFV strains or immunocompromised hosts. Non-human primates (NHPs) recapitulate human disease, but they require specialized facilities and training, are often in short supply and cost-prohibitive, and can present ethical concerns. The limitations in studying the mosquito vectors for YFV infection include inconsistency in the laboratory environment, the requirement for a high containment insectary, and difficulty in maintaining sylvatic mosquitoes. In this review, we discuss the roles of animal models and arthropod vector studies in understanding epidemic emergence.
Use of Whole-Genome Sequencing to Explore Mycobacterium tuberculosis Complex Circulating in a Hotspot Department in France
Authors: Billard-Pomares Typhaine , Marin Julie , Quagliaro Pauline , Méchaï Frédéric , Walewski Violaine , Dziri Samira , Carbonnelle Etienne
Published: August 2022

The Seine-Saint-Denis is the French metropolitan department with the highest incidence of tuberculosis (TB). Our aim was to explore epidemiological and phylogenetic characteristics of TB strains in this hotspot department. We performed WGS on 227 strains of Mycobacterium tuberculosis complex isolated from patients at the Avicenne Hospital from 2016 to 2021 and randomly selected to represent the clinical diversity of French TB localization. Clinical and demographic data were recorded for each TB patient. The mean age of patients was 36 years old. They came from Africa (44%), Asia (27%), Europe (26%) and America (3%). Strains isolated from extrapulmonary samples were associated with Asian patients, whereas strains isolated from pulmonary samples were associated with European patients. We observed a high level of lineage diversity in line with the known worldwide diversity. Interestingly, lineage 3 was associated with lymph node TB. Additionally, the sensitivity of WGS for predicting resistance was 100% for rifampicin, isoniazid and ethambutol and 66.7% for pyrazinamide. The global concordance with drug-susceptibility testing using the phenotypic approach was 97%. In microbiology laboratories, WGS turns out to be an essential tool for better understanding local TB epidemiology, with direct access to circulating lineage identification and to drug susceptibilities to first- and second-line anti-TB drugs.
Hydrocarbons Biodegradation by Rhodococcus: Assimilation of Hexadecane in Different Aggregate States
Authors: Thi Mo Luong , Irina Puntus , Natalia Suzina , Irina Nechaeva , Lenar Akhmetov , Andrey Filonov , Ekaterina Akatova , Sergey Alferov , Olga Ponamoreva
Published: August 2022

The aim of our study was to reveal the peculiarities of the adaptation of rhodococci to hydrophobic hydrocarbon degradation at low temperatures when the substrate was in solid states. The ability of actinobacteria Rhodococcus erythropolis (strains X5 and S67) to degrade hexadecane at 10 °C (solid hydrophobic substrate) and 26 °C (liquid hydrophobic substrate) is described. Despite the solid state of the hydrophobic substrate at 10 °C, bacteria demonstrate a high level of its degradation (30–40%) within 18 days. For the first time, we show that specialized cellular structures are formed during the degradation of solid hexadecane by Rhodococcus at low temperatures: intracellular multimembrane structures and surface vesicles connected to the cell by fibers. The formation of specialized cellular structures when Rhodococcus bacteria are grown on solid hexadecane is an important adaptive trait, thereby contributing to the enlargement of a contact area between membrane-bound enzymes and a hydrophobic substrate.
Identification and Characterization of Bacteria-Derived Antibiotics for the Biological Control of Pea Aphanomyces Root Rot
Authors: Lai Xiao , Niroula Dhirendra , Burrows Mary , Wu Xiaogang , Yan Qing
Published: August 2022

Antibiosis has been proposed to contribute to the beneficial bacteria-mediated biocontrol against pea Aphanomyces root rot caused by the oomycete pathogen Aphanomyces euteiches. However, the antibiotics required for disease suppression remain unknown. In this study, we found that the wild type strains of Pseudomonas protegens Pf-5 and Pseudomonas fluorescens 2P24, but not their mutants that lack 2,4-diacetylphloroglucinol, strongly inhibited A. euteiches on culture plates. Purified 2,4-diacetylphloroglucinol compound caused extensive hyphal branching and stunted hyphal growth of A. euteiches. Using a GFP-based transcriptional reporter assay, we found that expression of the 2,4-diacetylphloroglucinol biosynthesis gene phlAPf-5 is activated by germinating pea seeds. The 2,4-diacetylphloroglucinol producing Pf-5 derivative, but not its 2,4-diacetylphloroglucinol non-producing mutant, reduced disease severity caused by A. euteiches on pea plants in greenhouse conditions. This is the first report that 2,4-diacetylphloroglucinol produced by strains of Pseudomonas species plays an important role in the biocontrol of pea Aphanomyces root rot.
Achieving Antimicrobial Stewardship on the Global Scale: Challenges and Opportunities
Authors: Pinto Ferreira Jorge , Battaglia Daniela , Dorado García Alejandro , Tempelman KimAnh , Bullon Carmen , Motriuc Nelea , Caudell Mark , Cahill Sarah , Song Junxia , LeJeune Jeffrey
Published: August 2022

Antimicrobial resistance (AMR) has been clearly identified as a major global health challenge. It is a leading cause of human deaths and also has a toll on animals, plants, and the environment. Despite the considerable socio-economic impacts, the level of awareness of the problem remains woefully inadequate, and antimicrobials are not generally recognized as a global common good, one that everyone has a role and responsibility to conserve. It is imperative for antimicrobial stewardship to be more widely implemented to achieve better control of the AMR phenomenon. The Food and Agriculture Organization (FAO) of the United Nations plays an important role in promoting and facilitating antimicrobial stewardship. The specific needs to be addressed and barriers to be overcome, in particular, in low- and middle-income countries in order to implement antimicrobial stewardship practices in agrifood systems are being identified. As a global community, it is essential that we now move beyond discussing the AMR problem and focus on implementing solutions. Thus, FAO provides multi-pronged support for nations to improve antimicrobial stewardship through programs to strengthen governance, increase awareness, develop and enhance AMR surveillance, and implement best practices related to antimicrobial resistance in agrifood systems. For example, FAO is developing a platform to collect data on AMR in animals and antimicrobial use (AMU) in plants (InFARM), working on a campaign to reduce the need to use antimicrobials, studying the use of alternatives to the use of antimicrobials (especially those used for growth promotion) and actively promoting the implementation of the Codex Alimentarius AMR standards. Together, these will contribute to the control of AMR and also bring us closer to the achievement of multiple sustainable development goals.
Detection of Foodborne Pathogens in Acute Gastroenteritis Patient’s Stool Samples Using the BioFire® FilmArray® Gastrointestinal PCR Panel in the Republic of Trinidad and Tobago, West Indies
Authors: Lakhan Carelene , Badrie Neela , Ramsubhag Adash , Indar Lisa
Published: August 2022

In 2009, the burden of illness study for acute gastroenteritis in Trinidad and Tobago highlighted that ~10% of stool samples tested were positive for a foodborne pathogen. The study also noted that limited laboratory screening for pathogens contributed to a lack of etiology as public health hospitals only routinely tested for Salmonella and Shigella, and sometimes for Escherichia coli and Campylobacter. To better understand the foodborne pathogens responsible for acute gastroenteritis, enhanced testing using the BioFire® FilmArray® Gastrointestinal PCR panel was used to screen diarrheal stool samples for 22 pathogens from patients in 2018. The five general public health hospitals (San Fernando, Mt. Hope, Port of Spain, Sangre Grande, and Tobago) were notified of research activities and diarrheal stool samples were collected from all acute gastroenteritis patients. A total of 66 stools were screened and ~30% of samples tested positive for a foodborne pathogen. The current study showed that a much wider range of enteric pathogens were associated with acute gastroenteritis in Trinidad and Tobago than previously reported in 2009. These findings can be used by health officials to guide appropriate interventions, as well as to provide evidence for adoption of the PCR panel detection method at public health hospitals to benefit patient care.
Petrogenesis and Tectonic Implication of the Hongtaiping High-Mg Diorite in the Wangqing Area, NE China: Constraints from Geochronology, Geochemistry and Hf Isotopes
Authors: Lu Siyu , Ren Yunsheng , Yang Qun , Hao Yujie , Zhao Xuan
Published: August 2022

This study presents new data from zircon U–Pb dating and Hf isotope analysis, as well as whole-rock major- and trace-element compositions of the Hongtaiping high-Mg diorite in the Wangqing area of Yanbian, NE China. Laser ablation inductively coupled plasma mass spectrometry (LA–ICP–MS) zircon U–Pb dating gives an eruption age of ca. 267 Ma for the high-Mg diorite. These samples have MgO contents of 13.30% to 16.58% and high transition metal element concentrations, classified as sanukite. Their rare earth element (REE) contents range from 45.2 to 68.4 ppm and are characterized by slightly positive Eu anomalies (Eu/Eu* = 1.08–1.17). They show enrichment in light REEs (LREEs) and depletion in heavy REEs (HREEs), with LREE/HREE ratios = 6.54–6.97 and (La/Yb)N values = 7.24–8.08. The Hongtaiping high-Mg diorite is enriched in Rb, U, K, and Sr, but depleted in Th, Nb, and Ta. High MgO contents, Mg# values, and transition metal element concentrations imply that the magma experienced insignificant crystallization fractionation and crustal contamination. Relatively homogenous positive Hf isotopic values indicate that the original magma was generated by the partial melting of a depleted mantle wedge that was metasomatized by subducting slab fluids. The magma was generated by the moderate degree partial melting (20%–30%) of a garnet lherzolite source. Combined with previous studies, this shows that the high-Mg diorite was formed by the northward subduction of the Paleo-Asian oceanic plate during the Middle Permian.
Interaction of Ge(Si) Self-Assembled Nanoislands with Different Modes of Two-Dimensional Photonic Crystal
Authors: Stepikhova Margarita , Dyakov Sergey , Peretokin Artem , Shaleev Mikhail , Rodyakina Ekaterina , Novikov Alexey
Published: August 2022

The interaction of Ge(Si)/SOI self-assembled nanoislands with modes of photonic crystal slabs (PCS) with a hexagonal lattice is studied in detail. Appropriate selection of the PCS parameters and conditions for collecting the photoluminescence (PL) signal allowed to distinguish the PCS modes of different physical nature, particularly the radiative modes and modes associated to the bound states in the continuum (BIC). It is shown that the radiative modes with relatively low Q-factors could provide a increase greater than an order of magnitude in the integrated PL intensity in the wavelength range of 1.3–1.55 µm compared to the area outside of PCS at room temperature. At the same time, the interaction of Ge(Si) islands emission with the BIC-related modes provides the peak PL intensity increase of more than two orders of magnitude. The experimentally measured Q-factor of the PL line associated with the symmetry-protected BIC mode reaches the value of 2600.
Monolithic Integration of O-Band InAs Quantum Dot Lasers with Engineered GaAs Virtual Substrate Based on Silicon
Authors: Xu Buqing , Wang Guilei , Du Yong , Miao Yuanhao , Li Ben , Zhao Xuewei , Lin Hongxiao , Yu Jiahan , Su Jiale , Dong Yan , Ye Tianchun , Radamson Henry H.
Published: August 2022

The realization of high-performance Si-based III-V quantum-dot (QD) lasers has long attracted extensive interest in optoelectronic circuits. This manuscript presents InAs/GaAs QD lasers integrated on an advanced GaAs virtual substrate. The GaAs layer was originally grown on Ge as another virtual substrate on Si wafer. No patterned substrate or sophisticated superlattice defect-filtering layer was involved. Thanks to the improved quality of the comprehensively modified GaAs crystal with low defect density, the room temperature emission wavelength of this laser was allocated at 1320 nm, with a threshold current density of 24.4 A/cm−2 per layer and a maximum single-facet output power reaching 153 mW at 10 °C. The maximum operation temperature reaches 80 °C. This work provides a feasible and promising proposal for the integration of an efficient O-band laser with a standard Si platform in the near future.
Alternative Controlling Agent of Theobroma grandiflorum Pests: Nanoscale Surface and Fractal Analysis of Gelatin/PCL Loaded Particles Containing Lippia origanoides Essential Oil
Authors: Rocha Ana Luisa Farias , de Aguiar Nunes Ronald Zico , Matos Robert Saraiva , da Fonseca Filho Henrique Duarte , de Araújo Bezerra Jaqueline , Lima Alessandra Ramos , Guimarães Francisco Eduardo Gontijo , Pamplona Ana Maria Santa Rosa , Majolo Cláudia , de Souza Maria Geralda , Campelo Pedro Henrique , Ţălu Ştefan , Bagnato Vanderlei Salvador , Inada Natalia Mayumi , Sanches Edgar Aparecido
Published: August 2022

A new systematic structural study was performed using the Atomic Force Microscopy (AFM) reporting statistical parameters of polymeric particles based on gelatin and poly-ε-caprolactone (PCL) containing essential oil from Lippia origanoides. The developed biocides are efficient alternative controlling agents of Conotrachelus humeropictus and Moniliophtora perniciosa, the main pests of Theobroma grandiflorum. Our results showed that the particles morphology can be successfully controlled by advanced stereometric parameters, pointing to an appropriate concentration of encapsulated essential oil according to the particle surface characteristics. For this reason, the absolute concentration of 1000 µg·mL−1 (P1000 system) was encapsulated, resulting in the most suitable surface microtexture, allowing a faster and more efficient essential oil release. Loaded particles presented zeta potential around (–54.3 ± 2.3) mV at pH = 8, and particle size distribution ranging from 113 to 442 nm. The hydrodynamic diameter of 90% of the particle population was found to be up to (405 ± 31) nm in the P1000 system. The essential oil release was evaluated up to 80 h, with maximum release concentrations of 63% and 95% for P500 and P1000, respectively. The best fit for the release profiles was obtained using the Korsmeyer–Peppas mathematical model. Loaded particles resulted in 100% mortality of C. humeropictus up to 48 h. The antifungal tests against M. perniciosa resulted in a minimum inhibitory concentration of 250 µg·mL−1, and the P1000 system produced growth inhibition up to 7 days. The developed system has potential as alternative controlling agent, due to its physical stability, particle surface microtexture, as well as pronounced bioactivity of the encapsulated essential oil.
Gamma-Ray-Induced Structural Transformation of GQDs towards the Improvement of Their Optical Properties, Monitoring of Selected Toxic Compounds, and Photo-Induced Effects on Bacterial Strains
Authors: Dorontic Sladjana , Bonasera Aurelio , Scopelliti Michelangelo , Markovic Olivera , Bajuk Bogdanović Danica , Ciasca Gabriele , Romanò Sabrina , Dimkić Ivica , Budimir Milica , Marinković Dragana , Jovanovic Svetlana
Published: August 2022

Structural modification of different carbon-based nanomaterials is often necessary to improve their morphology and optical properties, particularly the incorporation of N-atoms in graphene quantum dots (GQDs). Here, a clean, simple, one-step, and eco-friendly method for N-doping of GQDs using gamma irradiation is reported. GQDs were irradiated in the presence of the different ethylenediamine (EDA) amounts (1 g, 5 g, and 10 g) and the highest % of N was detected in the presence of 10 g. N-doped GQDs emitted strong, blue photoluminescence (PL). Photoluminescence quantum yield was increased from 1.45, as obtained for non-irradiated dots, to 7.24% for those irradiated in the presence of 1 g of EDA. Modified GQDs were investigated as a PL probe for the detection of insecticide Carbofuran (2,2-Dimethyl-2,3-dihydro-1-benzofuran-7-yl methylcarbamate) and herbicide Amitrole (3-amino-1,2,4-triazole). The limit of detection was 5.4 μmol L−1 for Carbofuran. For the first time, Amitrole was detected by GQDs in a turn-off/turn-on mechanism using Pd(II) ions as a quenching agent. First, Pd(II) ions were quenched (turn-off) PL of GQDs, while after Amitrole addition, PL was recovered linearly with Amitrole concentration (turn-on). LOD was 2.03 μmol L−1. These results suggest that modified GQDs can be used as an efficient new material for Carbofuran and Amitrole detection. Furthermore, the phototoxicity of dots was investigated on both Gram-positive and Gram-negative bacterial strains. When bacterial cells were exposed to different GQD concentrations and illuminated with light of 470 nm wavelength, the toxic effects were not observed.
Photocatalytic Hydrogen Production from Aqueous Solutions of Glucose and Xylose over Layered Perovskite-like Oxides HCa2Nb3O10, H2La2Ti3O10 and Their Inorganic-Organic Derivatives
Authors: Kurnosenko Sergei , Voytovich Vladimir , Silyukov Oleg , Rodionov Ivan , Zvereva Irina
Published: August 2022

Nowadays, the efficient conversion of plant biomass components (alcohols, carbohydrates, etc.) into more energy-intensive fuels, such as hydrogen, is one of the urgent scientific and technological problems. The present study is the first one focused on the photoinduced hydrogen evolution from aqueous D-glucose and D-xylose using layered perovskite-like oxides HCa2Nb3O10, H2La2Ti3O10, and their organically modified derivatives that have previously proven themselves as highly active photocatalysts. The photocatalytic performance was investigated for the bare compounds and products of their surface modification with a 1 mass. % Pt cocatalyst. The photocatalytic experiments followed an innovative scheme including dark stages as well as the control of the reaction suspension’s pH and composition. The study has revealed that the inorganic−organic derivatives of the layered perovskite-like oxides can provide efficient conversion of carbohydrates into hydrogen fuel, being up to 8.3 times more active than the unmodified materials and reaching apparent quantum efficiency of 8.8%. Based on new and previously obtained data, it was shown that the oxides’ interlayer space functions as an additional reaction zone in the photocatalytic hydrogen production and the contribution of this zone to the overall activity is dependent on the steric characteristics of the sacrificial agent used.