bluuebunny/crossref_metadata_2025 huggingface dataset:
GC content of plant genes is linked to past gene duplications
Authors: Bowers John E. , Tang Haibao , Burke John M. , Paterson Andrew H.
Published: January 2022

The frequency of G and C nucleotides in genomes varies from species to species, and sometimes even between different genes in the same genome. The monocot grasses have a bimodal distribution of genic GC content absent in dicots. We categorized plant genes from 5 dicots and 4 monocot grasses by synteny to related species and determined that syntenic genes have significantly higher GC content than non-syntenic genes at their 5`-end in the third position within codons for all 9 species. Lower GC content is correlated with gene duplication, as lack of synteny to distantly related genomes is associated with past interspersed gene duplications. Two mutation types can account for biased GC content, mutation of methylated C to T and gene conversion from A to G. Gene conversion involves non-reciprocal exchanges between homologous alleles and is not detectable when the alleles are identical or heterozygous for presence-absence variation, both likely situations for genes duplicated to new loci. Gene duplication can cause production of siRNA which can induce targeted methylation, elevating mC→T mutations. Recently duplicated plant genes are more frequently methylated and less likely to undergo gene conversion, each of these factors synergistically creating a mutational environment favoring AT nucleotides. The syntenic genes with high GC content in the grasses compose a subset that have undergone few duplications, or for which duplicate copies were purged by selection. We propose a “biased gene duplication / biased mutation” (BDBM) model that may explain the origin and trajectory of the observed link between duplication and genic GC bias. The BDBM model is supported by empirical data based on joint analyses of 9 angiosperm species with their genes categorized by duplication status, GC content, methylation levels and functional classes.
Respiratory tract infections and gut microbiome modifications: A systematic review
Authors: Woodall Claire A. , McGeoch Luke J. , Hay Alastair D. , Hammond Ashley
Published: January 2022

Respiratory tract infections (RTIs) are extremely common and can cause gastrointestinal tract symptoms and changes to the gut microbiota, yet these effects are poorly understood. We conducted a systematic review to evaluate the reported evidence of gut microbiome alterations in patients with a RTI compared to healthy controls (PROSPERO: CRD42019138853). We systematically searched Medline, Embase, Web of Science, Cochrane and the Clinical Trial Database for studies published between January 2015 and June 2021. Studies were eligible for inclusion if they were human cohorts describing the gut microbiome in patients with an RTI compared to healthy controls and the infection was caused by a viral or bacterial pathogen. Dual data screening and extraction with narrative synthesis was performed. We identified 1,593 articles and assessed 11 full texts for inclusion. Included studies (some nested) reported gut microbiome changes in the context of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) (n = 5), influenza (H1N1 and H7N9) (n = 2), Tuberculosis (TB) (n = 4), Community-Acquired Pneumonia CAP (n = 2) and recurrent RTIs (rRTI) (n = 1) infections. We found studies of patients with an RTI compared to controls reported a decrease in gut microbiome diversity (Shannon) of 1.45 units (95% CI, 0.15–2.50 [p, <0.0001]) and a lower abundance of taxa (p, 0.0086). Meta-analysis of the Shannon value showed considerable heterogeneity between studies (I2, 94.42). Unbiased analysis displayed as a funnel plot revealed a depletion of Lachnospiraceae, Ruminococcaceae and Ruminococcus and enrichment of Enterococcus. There was an important absence in the lack of cohort studies reporting gut microbiome changes and high heterogeneity between studies may be explained by variations in microbiome methods and confounder effects. Further human cohort studies are needed to understand RTI-induced gut microbiome changes to better understand interplay between microbes and respiratory health.
Critical factors that affect the functioning of a research and evaluation capacity building partnership: A causal loop diagram
Authors: Tobin Rochelle , Crawford Gemma , Hallett Jonathan , Maycock Bruce Richard , Lobo Roanna
Published: January 2022

Introduction

Public health policy and practice is strengthened by the application of quality evidence to decision making. However, there is limited understanding of how initiatives that support the generation and use of evidence in public health are operationalised. This study examines factors that support the internal functioning of a partnership, the Western Australian Sexual Health and Blood-borne Virus Applied Research and Evaluation Network (SiREN). SiREN aims to build research and evaluation capacity and increase evidence-informed decision making in a public health context.

Methods

This study was informed by systems concepts. It developed a causal loop diagram, a type of qualitative system model that illustrated the factors that influence the internal operation of SiREN. The causal loop diagram was developed through an iterative and participatory process with SiREN staff and management (n = 9) via in-depth semi-structured interviews (n = 4), workshops (n = 2), and meetings (n = 6).

Results

Findings identified critical factors that affected the functioning of SiREN. Central to SiREN’s ability to meet its aims was its capacity to adapt within a dynamic system. Adaptation was facilitated by the flow of knowledge between SiREN and system stakeholders and the expertise of the team. SiREN demonstrated credibility and capability, supporting development of new, and strengthening existing, partnerships. This improved SiREN’s ability to be awarded new funding and enhanced its sustainability and growth. SiREN actively balanced divergent stakeholder interests to increase sustainability.

Conclusion

The collaborative development of the diagram facilitated a shared understanding of SiREN. Adaptability was central to SiREN achieving its aims. Monitoring the ability of public health programs to adapt to the needs of the systems in which they work is important to evaluate effectiveness. The detailed analysis of the structure of SiREN and how this affects its operation provide practical insights for those interested in establishing a similar project.
Imputation by feature importance (IBFI): A methodology to envelop machine learning method for imputing missing patterns in time series data
Authors: Mir Adil Aslam , Kearfott Kimberlee Jane , Çelebi Fatih Vehbi , Rafique Muhammad
Published: January 2022

A new methodology, imputation by feature importance (IBFI), is studied that can be applied to any machine learning method to efficiently fill in any missing or irregularly sampled data. It applies to data missing completely at random (MCAR), missing not at random (MNAR), and missing at random (MAR). IBFI utilizes the feature importance and iteratively imputes missing values using any base learning algorithm. For this work, IBFI is tested onsoil radon gas concentration (SRGC)data. XGBoost is used as the learning algorithm and missing data are simulated using R for different missingness scenarios. IBFI is based on the physically meaningful assumption that SRGC depends upon environmental parameters such as temperature and relative humidity. This assumption leads to a model obtained from the complete multivariate series where the controls are available by taking the attribute of interest as a response variable. IBFI is tested against other frequently used imputation methods, namely mean, median, mode, predictive mean matching (PMM), and hot-deck procedures. The performance of the different imputation methods was assessed using root mean squared error (RMSE), mean squared log error (MSLE), mean absolute percentage error (MAPE), percent bias (PB), and mean squared error (MSE) statistics. The imputation process requires more attention when multiple variables are missing in different samples, resulting in challenges to machine learning methods because some controls are missing. IBFI appears to have an advantage in such circumstances. For testing IBFI, Radon Time Series Data (RTS) has been used and data was collected from1stMarch 2017to the11thof May 2018, including4seismic activities that have taken place during the data collection time.
Phytoremediation of nickel by quinoa: Morphological and physiological response
Authors: Haseeb Muhammad , Iqbal Shahid , Hafeez Muhammad Bilal , Saddiq Muhammad Sohail , Zahra Noreen , Raza Ali , lbrahim Muhammad Usman , Iqbal Javaid , Kamran Muhammad , Ali Qasim , Javed Talha , Ali Hayssam M. , Siddiqui Manzer H.
Published: January 2022

The amount of soil contaminated with heavy metal increases due to urbanization, industrialization, and anthropogenic activities. Quinoa is considered a useful candidate in the remediation of such soil. In this pot experiment, the phytoextraction capacity of quinoa lines (A1, A2, A7, and A9) against different nickel (Ni) concentrations (0, 50, and 100 mg kg-1) were investigated. Required Ni concentrations were developed in polythene bags filled with sandy loam soil using nickel nitrate salt prior to two months of sowing and kept sealed up to sowing. Results showed that translocation of Ni increased from roots to shoots with an increase in soil Ni concentration in all lines. A2 line accumulated high Ni in leaf compared to the root as depicted by translocation factor 3.09 and 3.21 when grown at soil having 50 and 100 Ni mg kg-1, respectively. While, in the case of root, A7 accumulated high Ni followed by A9, A1, and A2, respectively. There was a 5–7% increased seed yield by 50 mg kg-1 Ni in all except A1 compared to control. However, growth and yield declined with a further increase in Ni level. The maximum reduction in yield was noticed in A9, which was strongly linked with poor physiological performance, e.g., chlorophyll a, b, and phenolic contents. Ni concentrations in the seed of all lines were within the permissible value set (67 ppm) by FAO/WHO. The result of the present study suggests that quinoa is a better accumulator of Ni. This species can provide the scope of decontamination of heavy metal polluted soil. The screened line can be used for future quinoa breeding programs for bioremediation and phytoextraction purpose.
Effect of dietary supplementation of lauric acid on growth performance, antioxidative capacity, intestinal development and gut microbiota on black sea bream (Acanthopagrus schlegelii)
Authors: Ullah Sami , Zhang Jinzhi , Xu Bingying , Tegomo Arnaud Fabrice , Sagada Gladstone , Zheng Lu , Wang Lei , Shao Qingjun
Published: January 2022

A feeding trial of eight weeks was conducted to examine the influence of food supplementation with lauric acid (LA) onAcanthopagrus schlegelii(juvenile black sea bream). A 24 percent fish meal baseline diet was created, while the other two diets were generated with dietary supplementation of graded points of LA at 0.1 percent and 0.8 percent, respectively. Each diet was given a triplicate tank with 20 fish weighing 6.22 ± 0.19 g. In comparison with the control group, the weight gain rate, growth rate, as well as feed efficiency of fish fed of 0.1 percent diet of LA were considerably (P < 0.05) greater. The total body and dorsal muscle proximate compositions did not change significantly between groups (P > 0.05). Triglyceride (TG) content was considerably (P < 0.05) greater in the LA-supplemented meals eating group in comparison with the control group. In the group eating LA-supplemented meals, the height of villus and the number of goblet cells/villus were considerably (P < 0.05) larger. The microbial makeup of the gut was also studied. The differences in phyla, class, and family level were not statistically significant (P > 0.05). Firmicutes in the phylum, Betaproteobacteri, Gammaproteobacteria, and Clostridia in the class, and Clostridiaceae in the family were all substantially increased with higher levels of LA supplementation (P < 0.05). According to the findings of this study, an LA-supplemented diet improves fish development, antioxidative capability, gut microbiota and intestinal health.
Delays in the presentation and diagnosis of women with breast cancer in Yogyakarta, Indonesia: A retrospective observational study
Authors: Hutajulu Susanna Hilda , Prabandari Yayi Suryo , Bintoro Bagas Suryo , Wiranata Juan Adrian , Widiastuti Mentari , Suryani Norma Dewi , Saptari Rorenz Geraldi , Taroeno-Hariadi Kartika Widayati , Kurnianda Johan , Purwanto Ibnu , Hardianti Mardiah Suci , Allsop Matthew John
Published: January 2022

Purpose

To investigate factors associated with delays in presentation and diagnosis of women with confirmed breast cancer (BC).

Methods

A cross-sectional study nested in an ongoing prospective cohort study of breast cancer patients at Dr Sardjito Hospital, Yogyakarta, Indonesia, was employed. Participants (n = 150) from the main study were recruited, with secondary information on demographic, clinical, and tumor variables collected from the study database. A questionnaire was used to gather data on other socioeconomic variables, herbal consumption, number of healthcare visits, knowledge-attitude-practice of BC, and open-ended questions relating to initial presentation. Presentation delay (time between initial symptom and first consultation) was defined as ≥3 months. Diagnosis delay was defined as ≥1 month between presentation and diagnosis confirmation. Impact on disease stage and determinants of both delays were examined. A Kruskal-Wallis test was used to assess the length and distribution of delays by disease stage. A multivariable logistic regression analysis was conducted to explore the association between delays, cancer stage and factors.

Results

Sixty-five (43.3%) patients had a ≥3-month presentation delay and 97 (64.7%) had a diagnosis confirmation by ≥1 month. Both presentation and diagnosis delays increased the risk of being diagnosed with cancer stage III-IV (odds ratio/OR 2.21, 95% CI 0.97–5.01, p = 0.059 and OR 3.03, 95% CI 1.28–7.19, p = 0.012). Visit to providers ≤3 times was significantly attributed to a reduced diagnosis delay (OR 0.15, 95% CI 0.06–0.37, p <0.001), while having a family history of cancer was significantly associated with increased diagnosis delay (OR 2.28, 95% CI 1.03–5.04, p = 0.042). The most frequent reasons for delaying presentation were lack of awareness of the cause of symptoms (41.5%), low perceived severity (27.7%) and fear of surgery intervention (26.2%).

Conclusions

Almost half of BC patients in our setting had a delay in presentation and 64.7% experienced a delay in diagnosis. These delays increased the likelihood of presentation with a more advanced stage of disease. Future research is required in Indonesia to explore the feasibility of evidence-based approaches to reducing delays at both levels, including educational interventions to increase awareness of BC symptoms and reducing existing complex and convoluted referral pathways for patients suspected of having cancer.
Efficient degradation of various emerging pollutants by wild type and evolved fungal DyP4 peroxidases
Authors: Athamneh Khawlah , Alneyadi Aysha , Alsadik Aya , Wong Tuck Seng , Ashraf Syed Salman
Published: January 2022

The accumulation of emerging pollutants in the environment remains a major concern as evidenced by the increasing number of reports citing their potential risk on environment and health. Hence, removal strategies of such pollutants remain an active area of investigation. One way through which emerging pollutants can be eliminated from the environment is by enzyme-mediated bioremediation. Enzyme-based degradation can be further enhanced via advanced protein engineering approaches. In the present study a sensitive and robust bioanalytical liquid chromatography-tandem mass spectrometry (LCMSMS)-based approach was used to investigate the ability of a fungal dye decolorizing peroxidase 4 (DyP4) and two of its evolved variants—that were previously shown to be H2O2 tolerant—to degrade a panel of 15 different emerging pollutants. Additionally, the role of a redox mediator was examined in these enzymatic degradation reactions. Our results show that three emerging pollutants (2-mercaptobenzothiazole (MBT), paracetamol, and furosemide) were efficiently degraded by DyP4. Addition of the redox mediator had a synergistic effect as it enabled complete degradation of three more emerging pollutants (methyl paraben, sulfamethoxazole and salicylic acid) and dramatically reduced the time needed for the complete degradation of MBT, paracetamol, and furosemide. Further investigation was carried out using pure MBT to study its degradation by DyP4. Five potential transformation products were generated during the enzymatic degradation of MBT, which were previously reported to be produced during different bioremediation approaches. The current study provides the first instance of the application of fungal DyP4 peroxidases in bioremediation of emerging pollutants.
The relationship between night-time light and socioeconomic factors in China and India
Authors: Han Guhuai , Zhou Tao , Sun Yuanheng , Zhu Shoujie
Published: January 2022

This paper re-examines the relationships between night-time light (NTL) and gross domestic product (GDP), population, road networks, and carbon emissions in China and India. Two treatments are carried out to those factors and NTL, which include simple summation in each administrative region (total data), and summation normalized by region area (density data). A series of univariate regression and multiple regression experiments are conducted in different countries and at different scales, in order to find the changes in the relationship between NTL and every parameter in different situations. Several statistical metrics, such as R2, Mean Relative Error (MRE), multiple regression weight coefficient, and Pearson’s correlation coefficient are given special attention. We found that GDP, as a comprehensive indicator, is more representative of NTL when the administrative region is relatively comprehensive or highly developed. However, when these regions are unbalanced or undeveloped, the representation of GDP becomes weak and other factors can have a more important influence on the multiple regression. Differences in the relationship between NTL and GDP in China and India can also be reflected in some other factors. In many cases, regression after normalization with the administrative area has a higher R2 value than the total regression. But it is highly influenced by a few highly developed regions like Beijing in China or Chandigarh in India. After the scale of the administrative region becomes fragmented, it is necessary to adjust the model to make the regression more meaningful. The relationship between NTL and carbon emissions shows obvious difference between China and India, and among provinces and counties in China, which may be caused by the different electric power generation and transmission in China and India. From these results, we can know how the NTL is reflected by GDP and other factors in different situations, and then we can make some adjustments.
Proteomics-based screening and antibiotic resistance assessment of clinical and sub-clinical Brucella species: An evolution of brucellosis infection control
Authors: Elbehiry Ayman , Aldubaib Musaad , Al Rugaie Osamah , Marzouk Eman , Abaalkhail Marwan , Moussa Ihab , El-Husseiny Mohamed H. , Abalkhail Adil , Rawway Mohammed
Published: January 2022

Brucellae are intracellular sneaky bacteria and they can elude the host’s defensive mechanisms, resulting in therapeutic failure. Therefore, the goal of this investigation was to rapid identification of Brucella species collected from animals and humans in Saudi Arabia, as well as to evaluate their resistance to antibiotics. On selective media, 364 animal samples as well as 70 human blood samples were cultured. Serological and biochemical approaches were initially used to identify a total of 25 probable cultured isolates. The proteomics of Brucella species were identified using the MALDI Biotyper (MBT) system, which was subsequently verified using real-time polymerase chain reaction (real-time PCR) and microfluidic electrophoresis assays. Both Brucella melitensis (B. melitensis) and Brucella abortus (B. abortus) were tested for antimicrobial susceptibility using Kirby Bauer method and the E-test. In total, 25 samples were positive for Brucella and included 11 B. melitensis and 14 B. abortus isolates. Twenty-two out of 25 (88%) and 24/25 (96%) of Brucella strains were recognized through the Vitek 2 Compact system. While MBT was magnificently identified 100% of the strains at the species level with a score value more than or equal to 2.00. Trimethoprim-sulfamethoxazole, rifampin, ampicillin-sulbactam, and ampicillin resistance in B. melitensis was 36.36%, 31.82%, 27.27%, and 22.70%, respectively. Rifampin, trimethoprim-sulfamethoxazole, ampicillin, and ampicillin-sulbactam resistance was found in 35.71%, 32.14%, 32.14%, and 28.57% of B. abortus isolates, correspondingly. MBT confirmed by microfluidic electrophoresis is a successful approach for identifying Brucella species at the species level. The resistance of B. melitensis and B. abortus to various antibiotics should be investigated in future studies.
Quantification of pulsed electric field for the rupture of giant vesicles with various surface charges, cholesterols and osmotic pressures
Authors: Ahamed Md. Kabir , Ahmed Marzuk , Karal Mohammad Abu Sayem
Published: January 2022

Electropermeabilization is a promising phenomenon that occurs when pulsed electric field with high frequency is applied to cells/vesicles. We quantify the required values of pulsed electric fields for the rupture of cell-sized giant unilamellar vesicles (GUVs) which are prepared under various surface charges, cholesterol contents and osmotic pressures. The probability of rupture and the average time of rupture are evaluated under these conditions. The electric field changes from 500 to 410 Vcm-1by varying the anionic lipid mole fraction from 0 to 0.60 for getting the maximum probability of rupture (i.e., 1.0). In contrast, the same probability of rupture is obtained for changing the electric field from 410 to 630 Vcm-1by varying the cholesterol mole fraction in the membranes from 0 to 0.40. These results suggest that the required electric field for the rupture decreases with the increase of surface charge density but increases with the increase of cholesterol. We also quantify the electric field for the rupture of GUVs containing anionic mole fraction of 0.40 under various osmotic pressures. In the absence of osmotic pressure, the electric field for the rupture is obtained 430 Vcm-1, whereas the field is 300 Vcm-1in the presence of 17 mOsmL-1, indicating the instability of GUVs at higher osmotic pressures. These investigations open an avenue of possibilities for finding the electric field dependent rupture of cell-like vesicles along with the insight of biophysical and biochemical processes.
Thermal stress affects proliferation and differentiation of turkey satellite cells through the mTOR/S6K pathway in a growth-dependent manner
Authors: Xu Jiahui , Strasburg Gale M. , Reed Kent M. , Velleman Sandra G.
Published: January 2022

Satellite cells (SCs) are stem cells responsible for post-hatch muscle growth through hypertrophy and in birds are sensitive to thermal stress during the first week after hatch. The mechanistic target of rapamycin (mTOR) signaling pathway, which is highly responsive to thermal stress in differentiating turkey pectoralis major (p. major) muscle SCs, regulates protein synthesis and the activities of SCs through a downstream effector, S6 kinase (S6K). The objectives of this study were: 1) to determine the effect of heat (43°C) and cold (33°C) stress on activity of the mTOR/S6K pathway in SCs isolated from the p. major muscle of one-week-old faster-growing modern commercial (NC) turkeys compared to those from slower-growing Randombred Control Line 2 (RBC2) turkeys, and 2) to assess the effect of mTOR knockdown on the proliferation, differentiation, and expression of myogenic regulatory factors of the SCs. Heat stress increased phosphorylation of both mTOR and S6K in both turkey lines, with greater increases observed in the RBC2 line. With cold stress, greater reductions in mTOR and S6K phosphorylation were observed in the NC line. Early knockdown of mTOR decreased proliferation, differentiation, and expression of myoblast determination protein 1 and myogenin in both lines independent of temperature, with the RBC2 line showing greater reductions in proliferation and differentiation than the NC line at 38° and 43°C. Proliferating SCs are more dependent on mTOR/S6K-mediated regulation than differentiating SCs. Thus, thermal stress can affect breast muscle hypertrophic potential by changing satellite cell proliferation and differentiation, in part, through the mTOR/S6K pathway in a growth-dependent manner. These changes may result in irreversible effects on the development and growth of the turkey p. major muscle.
Schistosoma mansoni α-N-acetylgalactosaminidase (SmNAGAL) regulates coordinated parasite movement and egg production
Authors: Hulme Benjamin J. , Geyer Kathrin K. , Forde-Thomas Josephine E. , Padalino Gilda , Phillips Dylan W. , Ittiprasert Wannaporn , Karinshak Shannon E. , Mann Victoria H. , Chalmers Iain W. , Brindley Paul J. , Hokke Cornelis H. , Hoffmann Karl F.
Published: January 2022

α-galactosidase (α-GAL) and α-N-acetylgalactosaminidase (α-NAGAL) are two glycosyl hydrolases responsible for maintaining cellular homeostasis by regulating glycan substrates on proteins and lipids. Mutations in the human genes encoding either enzyme lead to neurological and neuromuscular impairments seen in both Fabry- and Schindler/Kanzaki- diseases. Here, we investigate whether the parasitic blood fluke Schistosoma mansoni, responsible for the neglected tropical disease schistosomiasis, also contains functionally important α-GAL and α-NAGAL proteins. As infection, parasite maturation and host interactions are all governed by carefully-regulated glycosylation processes, inhibiting S. mansoni’s α-GAL and α-NAGAL activities could lead to the development of novel chemotherapeutics. Sequence and phylogenetic analyses of putative α-GAL/α-NAGAL protein types showed Smp_089290 to be the only S. mansoni protein to contain the functional amino acid residues necessary for α-GAL/α-NAGAL substrate cleavage. Both α-GAL and α-NAGAL enzymatic activities were higher in females compared to males (p<0.05; α-NAGAL > α-GAL), which was consistent with smp_089290’s female biased expression. Spatial localisation of smp_089290 revealed accumulation in parenchymal cells, neuronal cells, and the vitellaria and mature vitellocytes of the adult schistosome. siRNA-mediated knockdown (>90%) of smp_089290 in adult worms significantly inhibited α-NAGAL activity when compared to control worms (siLuc treated males, p<0.01; siLuc treated females, p<0.05). No significant reductions in α-GAL activities were observed in the same extracts. Despite this, decreases in α-NAGAL activities correlated with a significant inhibition in adult worm motility as well as in egg production. Programmed CRISPR/Cas9 editing of smp_089290 in adult worms confirmed the egg reduction phenotype. Based on these results, Smp_089290 was determined to act predominantly as an α-NAGAL (hereafter termed SmNAGAL) in schistosome parasites where it participates in coordinating movement and oviposition processes. Further characterisation of SmNAGAL and other functionally important glycosyl hydrolases may lead to the development of a novel anthelmintic class of compounds.
Advances and gaps in SARS-CoV-2 infection models
Authors: Muñoz-Fontela César , Widerspick Lina , Albrecht Randy A. , Beer Martin , Carroll Miles W. , de Wit Emmie , Diamond Michael S. , Dowling William E. , Funnell Simon G. P. , García-Sastre Adolfo , Gerhards Nora M. , de Jong Rineke , Munster Vincent J. , Neyts Johan , Perlman Stanley , Reed Douglas S. , Richt Juergen A. , Riveros-Balta Ximena , Roy Chad J. , Salguero Francisco J. , Schotsaert Michael , Schwartz Lauren M. , Seder Robert A. , Segalés Joaquim , Vasan Seshadri S. , Henao-Restrepo Ana María , Barouch Dan H.
Published: January 2022

The global response to Coronavirus Disease 2019 (COVID-19) is now facing new challenges such as vaccine inequity and the emergence of SARS-CoV-2 variants of concern (VOCs). Preclinical models of disease, in particular animal models, are essential to investigate VOC pathogenesis, vaccine correlates of protection and postexposure therapies. Here, we provide an update from the World Health Organization (WHO) COVID-19 modeling expert group (WHO-COM) assembled by WHO, regarding advances in preclinical models. In particular, we discuss how animal model research is playing a key role to evaluate VOC virulence, transmission and immune escape, and how animal models are being refined to recapitulate COVID-19 demographic variables such as comorbidities and age.
Simulation of fault detection in photovoltaic arrays
Authors: Lipták Róbert , Bodnár István
Published: January 2022

In solar systems, faults in the module and inverter occur in proportion to increased operating time. The identification of fault types and their effects is important information not only for manufacturers but also for investors, solar operators and researchers. Monitoring and diagnosing the condition of photovoltaic (PV) systems is becoming essential to maximize electric power generation, increase the reliability and lifetime of PV power plants. Any faults in the PV modules cause negative economic and safety impacts, reducing the performance of the system and making unwanted electric connections that can be dangerous for the user. In this paper have been classified all possible faults that happen in the PV system, and is presented to detect common PV array faults, such as open-circuit fault, line-to-line fault, ground fault, shading condition, degradation fault and bypass diode fault. In this studies examines the equivalent circuits of PV arrays with different topological configurations and fault conditions to evaluate the effects of these faults on the performance of a solar system, taking into account the influence of temperature and solar radiation. This work presents the validation of a simulated solar network by measuring the output curves of a low-power photovoltaic array system under real outdoor conditions. This method can be useful in future solar systems.
Detection of efficiency of microwave-enhanced sludge treatments by
dielectric measurements
Authors: Haranghy Laura , Jákói Zoltán , Hodúr Cecilia , Beszédes Sándor
Published: January 2022

Microwave irradiation is a promising pre-treatment method for sludge
stabilisation, but there are few studies focusing its effect on organic
matter solubility and biodegradability of wastewater and sludge originated
from the food industry. In our research, microwave irradiation was applied
standalone and in combination with alkaline treatment to enhance the
solubilisation and biodegradation of organic matter content of meat
industry wastewater and municipal sludge, respectively. The energy
efficiency was investigated, as well. Dielectric measurement is a suitable
method to detect physicochemical changes, therefore our research work
covered the determination of dielectric properties of the investigated
materials. Our experimental results have revealed that the lower power and
energy intensity microwave-alkaline treatments were the most efficient
pre-treatment process from energetically aspects to increase the organic
matter solubility and biodegradability of wastewater and sludge.
Furthermore, a strong linear correlation was found between the dielectric
constant and the indicators of the solubility of organic matter (SCOD/TCOD)
and aerobic biodegradability (BOD/COD) in both treated materials,
respectively. Our results show that the dielectric measurements can be
applied for detection of physicochemical changes, predict the improvement
of biodegradability, and considered as a promising method to estimate the
efficiency of sludge pre-treatment methods.
Micropropagation and In Vitro Inflorescence of Pentas lanceolata
Authors: Bodhipadma Kitti , Noichinda Sompoch , Tangtivaporn Chutikarn , Phanomchai Saowaros , Leung David W. M.
Published: January 2022

In this study, different concentrations of 6-benzyladenine (BA) on in vitro shoot and inflorescence inductions of P. lanceolata were investigated. The in vivo and in vitro floral characteristics of this plant were also compared. Nodal explants of P. lanceolata were cultured vertically with the cut ends inserted into semi-solid Murashige and Skoog (MS) medium supplemented with 0, 0.5, 1, 2, 4, and 8 mg L–1 BA. The results showed that the explants formed the highest numbers of shoots even when cultured in MS basal medium without any addition of BA, while the shoots formed in the explants cultured in MS medium supplemented with 1 mg L–1 BA were the longest. No inflorescence was found in the shoots cultured in MS medium supplemented with 8 mg L–1 BA, while the highest percentage of inflorescence induction was found in the shoots cultured in the medium supplemented with 0.5 mg L–1 BA. The apperances of in vivo and in vitro flowers of P. lanceolata were the same in many aspects except that the number of flower/inflorescence formed was different. In addition, water accumulation was observed only inside the in vitro flowers. Water deposit in the long tubular structure of P. lanceolata flower could cause anther injury, suggesting that flowers developed in vitro may not always produce pollen.
ON THE LAW OF DISTRIBUTION OF THE RATE OF FATIGUE FRACTURE
Authors: Karpov G. N.
Published: January 2022

The article discusses the correction of the law of development of fatigue cracks based on the application of the Fokker–Planck–Kolmogorov equation. The coefficient of variation of the fatigue crack propagation rate was chosen as the correction criterion. Its decrease brings the descriptions of the fatigue fracture process closer to engineering. The latter is especially important for specialists dealing with the assessment of the fatigue strength of metal-consuming structures, where mass formation of fatigue cracks is inevitable.
NEW METHODS AND TECHNOLOGIES FOR PROCESSING CARBON FIBER-REINFORCED PLASTICS
Authors: Galinovskiy A. L. , Tszya Chzhen’yuan’ , Tsypysheva S. N. , Ternovskih K. A. , Ryabenkova S. A. , Erokhin S. A.
Published: January 2022

The article deals with the application of new methods and approaches for machining of carbon plastics on the basis of the analysis of foreign information sources with a search depth of five years. The complex problems of composite materials processing, in particular, carbon plastics, the solutions of which have not yet been found in full, are noted. Applying of new methods of hole formation, part milling, hydro-abrasive and laser processing allows to obtain new output quality indicators is pointed out. The implementation of considered methods, developed by foreign scientists, may supplement the tools arsenal and technologies of composite materials processing at domestic enterprise. The importance of quality assurance of composites` complex surfaces processing and formation in aircraft and aerospace engineering, where utilization level of this material is constantly increasing, is indicated.
ASSESSMENT OF THE ECONOMIC EFFECT OF INNOVATION AT THE STAGES OF THE AIRCRAFT LIFE CYCLE
Authors: Samarin A. V. , Gyazova M. M.
Published: January 2022

The article presents the concept of information-functional communication of technological innovations with a block of indicators of economic impact in the early stages of the aircraft life cycle, based on quantitative changes in technical indicators and operational perfection of aircraft systems.
ADDER
Authors: Brysin A. N. , Zhuravleva Yu. A. , Mikaeva A. S. , Mikaeva S. A.
Published: January 2022

The article describes an electronic multifunctional adder for electricity metering SEM-3. The authors give the technical characteristics, the device and the principle of its operation. The presented adder is designed to monitor and account for the consumption of electricity generation and power directly from consumers, as well as in automated centralized accounting and control systems, and is designed for round-the-clock operation. The adder can collect and transmit information over six independent serial interfaces. The adder with a builtin GSM module provides bidirectional information exchange via cellular modem communication with remote devices and the transfer of accumulated data to the upper level of the automated electricity metering system. It provides bidirectional exchange of information over a local network with a PC over the built-in 10/100 Base-T Ethernet interface.
METHOD OF CALCULATION THE STABILITY OF AN EXCAVATOR EQUIPPED WITH A CONE ROLLER
Authors: Tilloev K. Z. , Kondakov S. V.
Published: January 2022

The construction and method of calculating the stability of a crawler excavator equipped with a new working body (cone roller) are considered. The calculation is made on two working positions (longitudinal and transverse) of the excavator, provided that the excavator must apply the maximum force on the working body at an angle of 90°. The force applied by the excavator boom to the cone roller during the introduction depends on the physical and mechanical properties of the compacted soil. The calculation method differs in that during the compaction of the roadbed, the cone sinks into the ground, and the excavator tends to roll in the direction of the rear track support roller, in contrast to the traditional danger of tipping over the front support roller when working with a bucket.
FUNDAMENTALS OF THE LUMP CRUSHING THEORY. WORKING PROCESSES OF CRUSHING AND SCREENING EQUIPMENT. LECTURE 8
Authors: Nizhegorodov A. I.
Published: January 2022

The article presents materials of Lecture 8 in Theory of carrying and lifting, construction and road vehicles and equipment, which describes the following issues: the rock properties, the rock crushing degree, the basics of the lump crushing theory and types of crushing machines. The technological process of crushing with a roll crusher is described; the values of forces acting in roll crushers are calculated.Along with the process of crushing, the article deals with the processes of segregation and concentration, the basic of the screening (fractionation) theory and features of the hydraulic classification of nonmetallic materials.
AIR TRAFFIC CONTROL BASICS
Authors: Sukhova T. S. , Aleksashina O. V. , Grinyuk O. N.
Published: January 2022

The concept of flight safety is considered, the features and purpose of the air traffic control system, the air traffic control complex, the capabilities of the system that ensure flight safety are presented.
OPTIMIZATION OF THE LONGITUDINAL STABILITY OF AN UNDERGROUND PIPELINE BY THE METHOD OF DICHOTOMY
Authors: Murzakhanov G. Kh. , Dzhokhaev D. A.
Published: January 2022

Use such parameters as ground density and pipe depth to optimize the longitudinal stability of the pipeline. Optimization of two parameters of the target function by the method of dichotomy and boundary of condition of termination of iterations. Definition of the target function for the regulation of the calculation of the longitudinal stability of underground pipelines. Development of the program in the programming language Python 3.7. Results processing and testing of the program.
COMBINED EXTRUSION OF GLASSES WITH A CONICAL BOTTOM. MECHANICAL AND MATHEMATICAL ANALYSIS OF THE FOURTH AND FIFTH VARIANTS OF THE PROCESS
Authors: Vorontsov A. L. , Lebedeva D. A.
Published: January 2022

Using the general methods of A. L. Vorontsov, a mechanical and mathematical study of the fourth and fifth variants of the process of combined extrusion of glasses with a conical bottom was carried out. All necessary design schemes are presented. Calculation formulas have been obtained that make it possible to determine the deformation forces and the magnitude of the plastic deformation areas for each possible variant of the plastic flow of the workpiece metal. These formulas also make it possible to determine which variant of deformation will occur in a particular case, and are necessary for the successful design of this operation. The results of confirming experiments are presented.
COMBINED EXTRUSION OF GLASSES WITH A CONICAL BOTTOM. KINEMATIC AND STRESS STATES OF A CYLINDRICAL PLASTIC REGION LOCATED UNDER THE FORMING GLASS WALL
Authors: Vorontsov A. L. , Lebedeva D. A.
Published: January 2022

For extrusion of glasses with a conical bottom using the method of plastic flow by A. L. Vorontsov, the kinematic and stress states of the extruded metal in the area of the plastic deformation center located under the formed wall of the glass and adjacent to the cylindrical section of the matrix were determined. The resulting formulas will be used to determine the stress state in the areas of the focus located under the punch end.
COMBINED EXTRUSION OF GLASSES WITH A CONICAL BOTTOM. KINEMATIC AND STRESS STATES OF THE PLASTIC REGION IN CONTACT WITH THE CONICAL SURFACE OF THE MATRIX
Authors: Vorontsov A. L. , Lebedeva D. A.
Published: January 2022

For the extrusion of glasses with a conical bottom using the method of plastic flow by A. L. Vorontsov, the kinematic and stress states of the extruded metal in the area of the plastic deformation zone in contact with the conical surface of the matrix were determined. The results are combined with the results obtained earlier for the cylindrical region located under the forming glass wall. The resulting formulas will be used to determine the stress state in the areas of the focus located under the end of the punch. The derived formula for the maximum pressure on the matrix wall is necessary for calculating the matrix strength and making an informed decision about the need for its banding.
A HYBRID ALGORITHM FOR FORMING THE SHORTEST TRAJECTORY BASED ON THE APPLICATION OF MULTI-AGENT LEARNING WITH REINFORCEMENT, THE SEARCH ALGORITHM A* AND EXCHANGE OF EXPERIENCE
Authors: Dubenko Yu. V. , Dyshkant E. E. , Timchenko N. N. , Rudeshko N. A.
Published: January 2022

The article presents a hybrid algorithm for the formation of the shortest trajectory for intelligent agents of a multi-agent system, based on the synthesis of methods of the reinforcement learning paradigm, the heuristic search algorithm A*, which has the functions of exchange of experience, as well as the automatic formation of subgroups of agents based on their visibility areas. The experimental evaluation of the developed algorithm was carried out by simulating the task of finding the target state in the maze in the Microsoft Unity environment. The results of the experiment showed that the use of the developed hybrid algorithm made it possible to reduce the time for solving the problem by an average of 12.7 % in comparison with analogs. The differences between the proposed new “hybrid algorithm for the formation of the shortest trajectory based on the use of multi-agent reinforcement learning, search algorithm A* and exchange of experience” from analogs are as follows: – application of the algorithm for the formation of subgroups of subordinate agents based on the “scope” of the leader agent for the implementation of a multi-level hierarchical system for managing a group of agents; – combining the principles of reinforcement learning and the search algorithm A*.
SERVERLESS COMPUTATIONS RESOURCE SCHEDULING BASED ON DATA DEPENDENCY
Authors: Kukushkin D. I. , Antonenko V. A.
Published: January 2022

The serverless computing model is becoming quite widespread. This model allows developers to create flexible and fault tolerant applications with an attractive billing model. The increasing complexity of serverless functions has led to the necessity to use serverless workflows – serverless functions invoking other serverless functions. However, such concept imposes certain requirements on the serverless functions that make distributed computations. The overhead of transferring data between serverless functions can significantly increase the execution time of a program using this approach. One way to reduce overhead is to improve serverless scheduling techniques. This paper discusses an approach to scheduling serverless computations based on data dependency analysis. We propose to divide the problem of planning of the computation of a composite serverless function into three stages. For each stage we provide a description by a mathematical model. We carried out a review of algorithms used to schedule resources by compilers and in parallel computing in multiprocessor systems to determine the best algorithm to implement in a prototype scheduler. For each algorithm, it was specified how it could be used for resource scheduling in serverless platforms. We provide a description of the developed prototype based on the Fission serverless platform. The prototype implements the critical path heuristic. It is shown that the improvements can significantly reduce the execution time up to two times for some types of serverless functions.
INFORMATION SYSTEMS PROACTIVE PROTECTION SUITE AGAINST NETWORK RECONNAISSANCE
Authors: Sokolovsky S. P.
Published: January 2022

The usage of known protection tools in information systems, including cryptographic ones, does not allow ensuring the confidentiality of information about its composition, structure and functioning algorithms, due to the fact that modern network technologies require addressable information in the service headers of the transmitted message packets. Strict dependence of information systems configurations on the quality requirements for the architecture, as well as established security policies set by regulators, causes them to have the properties of static, homogeneous and deterministic network parameters. This gives the adversary a number of indisputable advantages to non-compromising conduct network reconnaissance, high reliability of its results over a long period of time, as well as advance (planned) formation and application of the optimal set of tools to implement computer attacks. In this regard, there is a need to develop security technologies that replace static parameters of information systems with the dynamic ones. The analysis of existing technologies in the subject area under consideration showed a number of their inherent disadvantages, consisting in high resource intensity, insufficient performance and narrowness of the scope. In order to solve this problem, the author proposed a new technical solution that allows to level the disadvantages of known analogues and surpasses them by a number of criteria. The technical shape of the suite, consisting of three interconnected subsystems, that allows to mask information directions, the parameters of local area networks and manage the parameters of network connections with network reconnaissance tools, is presented and justified.