bluuebunny/crossref_metadata_2025 huggingface dataset:
Shrink and Eliminate: A Study of Post-Training Quantization and Repeated Operations Elimination in RNN Models
Authors: Rezk Nesma M. , Nordström Tomas , Ul-Abdin Zain
Published: April 2022

Recurrent neural networks (RNNs) are neural networks (NN) designed for time-series applications. There is a growing interest in running RNNs to support these applications on edge devices. However, RNNs have large memory and computational demands that make them challenging to implement on edge devices. Quantization is used to shrink the size and the computational needs of such models by decreasing weights and activation precision. Further, the delta networks method increases the sparsity in activation vectors by relying on the temporal relationship between successive input sequences to eliminate repeated computations and memory accesses. In this paper, we study the effect of quantization on LSTM-, GRU-, LiGRU-, and SRU-based RNN models for speech recognition on the TIMIT dataset. We show how to apply post-training quantization on these models with a minimal increase in the error by skipping quantization of selected paths. In addition, we show that the quantization of activation vectors in RNNs to integer precision leads to considerable sparsity if the delta networks method is applied. Then, we propose a method for increasing the sparsity in the activation vectors while minimizing the error and maximizing the percentage of eliminated computations. The proposed quantization method managed to compress the four models more than 85%, with an error increase of 0.6, 0, 2.1, and 0.2 percentage points, respectively. By applying the delta networks method to the quantized models, more than 50% of the operations can be eliminated, in most cases with only a minor increase in the error. Comparing the four models to each other under the quantization and delta networks method, we found that compressed LSTM-based models are the most-optimum solutions at low-error-rates constraints. The compressed SRU-based models are the smallest in size, suitable when higher error rates are acceptable, and the compressed LiGRU-based models have the highest number of eliminated operations.
Study of Transformed ηζ Networks via Zagreb Connection Indices
Authors: Hussain Muhammad , Rehman Atiq ur , Shekhovtsov Andrii , Asif Muhammad , Sałabun Wojciech
Published: April 2022

A graph is a tool for designing a system’s required interconnection network. The topology of such networks determines their compatibility. For the first time, in this work we construct subdivided ηζ network S(ηζΓ) and discussed their topology. In graph theory, there are a variety of invariants to study the topology of a network, but topological indices are designed in such a way that these may transform the graph into a numeric value. In this work, we study S(ηζΓ) via Zagreb connection indices. Due to their predictive potential for enthalpy, entropy, and acentric factor, these indices gain value in the field of chemical graph theory in a very short time. ηζΓ formed by ζ time repeated process which consists ηζ copies of graph Γ along with η2|V(Γ)|ζηζ−1 edges which used to join these ηζ copies of Γ. The free hand to choose the initial graph Γ for desired network S(ηζΓ) and its relation with chemical networks along with the repute of Zagreb connection indices enhance the worth of this study. These computations are theoretically innovative and aid topological characterization of S(ηζΓ).
Mapping Women’s and Men’s Pathways into Thailand’s Prisons for Homicide and Sex Offences: Utilising a Feminist Pathways Approach
Authors: Jeffries Samantha , Russell Tristan , Thipphayamongkoludom Yodsawadi , Rao Prarthana , Chuenurah Chontit , Phyu Swe Zin Linn , Zeren Iraz Rana
Published: April 2022

In feminist criminology, there is a growing body of research exploring pathways to prison, but few studies have specifically sought to map women’s journeys into the criminal justice system for crimes of physical violence and sex offending. Gender comparative research is sparse, and, to date, we know little about women and men imprisoned in Thailand for these types of crimes. Subsequently, in this paper, we report findings from a gender comparative feminist pathways study conducted in Thailand, with a specific focus on violence and sex offending; namely, homicide, sexual assault, human trafficking, and sex work-related offences. We utilise a qualitative analysis of life-history interviews to centre and value these women’s and men’s voices, establish their backstories, and thematically map their imprisonment trajectories. Three pathways to prison emerged: (1) lifestyles of contravention, (2) harmed and harming, and (3) destructive masculinity. Utilising the participants’ descriptions, we highlight similarities and variance by gender within and between these pathways.
Probing the Reaction Mechanisms of 3,5-Difluoro-2,4,6-Trinitroanisole (DFTNAN) through a Comparative Study with Trinitroanisole (TNAN)
Authors: Jiao Qingjie , Li Tianqi , Ou Yapeng , Jing Suming , Wang Fang
Published: April 2022

To probe the thermal decomposition mechanisms of a novel fluorinated low-melting-point explosive 3,5-difluoro-2,4,6-trinitroanisole (DFTNAN), a comparative study with trinitroanisole (TNAN) was performed under different heating conditions. The thermal decomposition processes and initial reactions were monitored by DSC-TG-FTIR-MS and T-jump-PyGC-MS coupling analyses, respectively. The results show that fluorine decreased the thermal stability of the molecular structure, and the trigger bond was transferred from the ortho-nitro group of the ether to the para-nitro group. The possible reaction pathway of DFTNAN after the initial bond breakage is the rupture of the dissociative nitro group with massive heat release, which induces the ring opening of benzene. Major side reactions include the generation of polycyclic compounds and fluorine atom migration. Fluorine affects the thermal stability and changes the reaction pathway, and fluorinated products appear in the form of fluorocarbons due to the high stability of the C-F bond.
Switching Diagram of Core-Shell FePt/Fe Nanocomposites for Bit Patterned Media
Authors: Wang Yuhui , Zheng Ying , Zhong Ziyi , Wang Zijun , Liang Yongfeng , Wu Pingping
Published: April 2022

In the current work, a core-shell type exchange coupled composite structure was constructed by micromagnetic simulation with a phase FePt core and an iron shell. Four types of switching loops with magnetic domain structure evolution were demonstrated. Based on the simulation results, a switching type diagram was constructed, which displays various hysteresis loops as a function of core radius and shell thickness. Furthermore, the effects of switching type and composite structure on the coercivity and remanent magnetization were predicted and discussed. This finding indicates that core-shell type FePt/Fe composite structure film has a large advantage in designing exchange-coupled bit patterned media to realize high-density storage devices at the nanoscale.
Fucoxanthin Prevents Long-Term Administration l-DOPA-Induced Neurotoxicity through the ERK/JNK-c-Jun System in 6-OHDA-Lesioned Mice and PC12 Cells
Authors: Liu Jingwangwei , Lu Yujia , Tang Min , Shao Fanghao , Yang Dongzi , Chen Shuchang , Xu Ziyi , Zhai Leilei , Chen Juanjuan , Li Qian , Wu Wei , Chen Haimin
Published: April 2022

As the most abundant marine carotenoid extracted from seaweeds, fucoxanthin is considered to have neuroprotective activity via its excellent antioxidant properties. Oxidative stress is regarded as an important starting factor for neuronal cell loss and necrosis, is one of the causes of Parkinson’s disease (PD), and is considered to be the cause of adverse reactions caused by the current PD commonly used treatment drug levodopa (l-DA). Supplementation with antioxidants early in PD can effectively prevent neurodegeneration and inhibit apoptosis in dopaminergic neurons. At present, the effect of fucoxanthin in improving the adverse effects triggered by long-term l-DA administration in PD patients is unclear. In the present study, we found that fucoxanthin can reduce cytotoxicity and suppress the high concentration of l-DA (200 μM)-mediated cell apoptosis in the 6-OHDA-induced PC12 cells through improving the reduction in mitochondrial membrane potential, suppressing ROS over-expression, and inhibiting active of ERK/JNK-c-Jun system and expression of caspase-3 protein. These results were demonstrated by PD mice with long-term administration of l-DA showing enhanced motor ability after intervention with fucoxanthin. Our data indicate that fucoxanthin may prove useful in the treatment of PD patients with long-term l-DA administration.
Polypropylene Hollow-Fiber Membrane Made Using the Dissolution-Induced Pores Method
Authors: Qiu Zhongyong , He Chunju
Published: April 2022

The efficient preparation of hydrophilic polypropylene membranes has always been a problem. Here, a twin-screw extruder was used to melt-blend ethylene-vinyl alcohol copolymer and polypropylene; then, hollow fibers were extrusion-molded with a spinneret and taken by a winder; after this, dimethyl sulfoxide was used to dissolve the ethylene-vinyl alcohol copolymer of the fiber to obtain a polypropylene hollow-fiber membrane. This procedure was used to study the effects of different contents and segment structure of ethylene-vinyl alcohol copolymer on the structure and filtration performance of the membranes; furthermore, the embedded factor and blocked factor were used to evaluate the ethylene-vinyl alcohol copolymer embedded in the matrix without dissolving and or being completely blocked in the matrix, respectively. The results show that the increase in ethylene-vinyl alcohol copolymer could reduce the embedded factor and increase the blocked factor. The increase in the polyethylene segments of ethylene-vinyl alcohol copolymer could increase both the embedded factor and blocked factor. The water permeation of the membrane reached 1300 Lm−2·h−1·bar−1 with a 100% rejection of ink (141 nm) and the elongation at break reached 188%, while the strength reached 22 MPa. The dissolution-induced pores method provides a completely viable alternative route for the preparation of polypropylene membranes.
Fabrication, Characterization and Drainage Capacity of Single-Channel Porous Alumina Ceramic Membrane Tube
Authors: Du Jianzhou , Xiao Xin , Ai Duomei , Liu Jingjin , Qiu Long , Chen Yuansheng , Zhu Kongjun , Wang Luming
Published: April 2022

The single-channel Al2O3-based porous ceramic membrane tubes (PCMT) were prepared with different grain size of Al2O3 powders by extrusion molding process, combing the traditional solid-phase sintering method. The effects of raw grain size and sintering temperature on the microstructure, phase structure, density, and porosity were investigated. The results revealed that with further increase in sintering temperature, the density of porous ceramics increases, while the porosity decreases, and the pore size decreases slightly. The pore size and porosity of porous ceramics increase with the increase in raw grain size, while the density decreases. Future, in order to study the water filtration of PCMT, the effect of porosity on the pressure distribution and flow velocity different cross-sectional areas with constant feed mass flow was analyzed using Fluent 19.0. It was found that an increase in the porosity from 30% to 45% with constant feed mass flow influenced transmembrane pressure, that varied from 216.06 kPa to 42.28 kPa, while the velocity change at the outlet was not obvious. Besides, it was observed that the surface pressure is almost constant along the radial direction of the pipe, and the velocity of water in the PCMT is increasing with the decreasing of distance to the outlet. It was also verified that the porosity being 39.64%, caused transmembrane pressure reaching to 77.83 kPa and maximum velocity of 2.301 m/s. These simulation and experimental results showed that the PCMT have good potential for water filtration.
Cardiovascular/Stroke Risk Stratification in Parkinson’s Disease Patients Using Atherosclerosis Pathway and Artificial Intelligence Paradigm: A Systematic Review
Authors: Suri Jasjit S. , Paul Sudip , Maindarkar Maheshrao A. , Puvvula Anudeep , Saxena Sanjay , Saba Luca , Turk Monika , Laird John R. , Khanna Narendra N. , Viskovic Klaudija , Singh Inder M. , Kalra Mannudeep , Krishnan Padukode R. , Johri Amer , Paraskevas Kosmas I.
Published: April 2022

Parkinson’s disease (PD) is a severe, incurable, and costly condition leading to heart failure. The link between PD and cardiovascular disease (CVD) is not available, leading to controversies and poor prognosis. Artificial Intelligence (AI) has already shown promise for CVD/stroke risk stratification. However, due to a lack of sample size, comorbidity, insufficient validation, clinical examination, and a lack of big data configuration, there have been no well-explained bias-free AI investigations to establish the CVD/Stroke risk stratification in the PD framework. The study has two objectives: (i) to establish a solid link between PD and CVD/stroke; and (ii) to use the AI paradigm to examine a well-defined CVD/stroke risk stratification in the PD framework. The PRISMA search strategy selected 223 studies for CVD/stroke risk, of which 54 and 44 studies were related to the link between PD-CVD, and PD-stroke, respectively, 59 studies for joint PD-CVD-Stroke framework, and 66 studies were only for the early PD diagnosis without CVD/stroke link. Sequential biological links were used for establishing the hypothesis. For AI design, PD risk factors as covariates along with CVD/stroke as the gold standard were used for predicting the CVD/stroke risk. The most fundamental cause of CVD/stroke damage due to PD is cardiac autonomic dysfunction due to neurodegeneration that leads to heart failure and its edema, and this validated our hypothesis. Finally, we present the novel AI solutions for CVD/stroke risk prediction in the PD framework. The study also recommends strategies for removing the bias in AI for CVD/stroke risk prediction using the PD framework.
Heat Dissipation Characteristics of IGBT Module Based on Flow-Solid Coupling
Authors: Tan Lipeng , Liu Peisheng , She Chenhui , Xu Pengpeng , Yan Lei , Quan Hui
Published: April 2022

With the increase of power level and integration in electric vehicle controllers, the heat flux of the key silicon-based IGBT (Insulated Gate Bipolar Transistor) device has reached its physical limit. At present, third-generation semiconductor devices including SiC MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistor) are gradually replacing the dominant IGBT module. The hybrid IGBT module consists of both and can improve the performance and reduce the cost of controllers. Limits due to the installation space, location, and other conditions in the car make it difficult to meet the requirements of controllers with an air-cooled heatsink due to their large size and limited heat dissipation capacity. A smaller and more powerful water-cooled heatsink case is required to ensure the heat dissipation of the IGBT in the controller. Based on previous experience in finite element numerical simulation, hydrodynamics calculation, and heat transfer calculation, ANSYS Workbench finite element software was used to analyze the thermal resistance of each structure inside the module and the heatsink structure. The fluid characteristics and heat transfer performance of three different flow channel structures were analyzed, and the design of the cooling flow fin was improved to provide a reference for the heat dissipation of the hybrid IGBT module.
Simultaneous Recovery of Niobium and Sulfur from Carbonate Niobite Ore with Flotation
Authors: Liu Shuang , Yang Lang , Yi Hao , Song Shaoxian
Published: April 2022

Exploring new ways to acquire niobium resources is essential to resolve niobium supply risks, due to the fact that, at present, 99% of niobium is controlled by only two countries. In the present work, a flotation technique was applied to separate niobium from low-grade niobite ore. To maximize the utilization of the original ore resources, pre-flotation was conducted to recover sulfur and eliminate the adverse effects of sulfide on niobite flotation. The obtained sulfur grade and recovery were 33.74% and 92.04%, respectively, and its concentration ratio was 40x. As for the niobite flotation, a closed-circuit experiment with one rougher flotation, three cleaner flotations, and two scavenger flotations was carried out to achieve the maximum niobite recovery. To further improve the niobite recovery, a leaching process with diluted HCl was employed; the final obtained Nb2O5 grade and recovery were 30.19% and 65.04%, respectively, and the concentration ratio reached 242x. Moreover, the economic evaluation implies that the flotation process can attract great positive interest.
The Hypolipidemic and Antioxidant Activity of Wheat Germ and Wheat Germ Protein in High-Fat Diet-Induced Rats
Authors: Liu Cong , Sun Yi , Yang Lei , Chen Yuxian , Ji Rigala , Wang Hao , Shi Jinghong , Wang Jilite
Published: April 2022

Background: So far, no articles have discussed the hypolipidemic effect of wheat germ protein in in vivo experiments. Objective: In this study, we investigated the effects of wheat germ protein (WGP, 300 mg/kg/day) and wheat germ (WG, 300 mg/kg/day) on cholesterol metabolism, antioxidant activities, and serum and hepatic lipids in rats fed a high-fat diet through gavage. Methodology: We used 4-week-old male Wistar 20 rats in our animal experiment. Biochemical indicators of fecal, serum and liver were tested by kits or chemical methods. We also conducted the cholesterol micellar solubility experiment in vitro. Results: After 28 days of treatment, our results showed that WGP significantly reduced the serum levels of total cholesterol (p < 0.05) and nonhigh-density lipoprotein cholesterol (p < 0.05), improved the enzymatic activities of cholesterol 7-α hydroxylase (p < 0.01) and low-density lipoprotein receptor (p < 0.01) and increased bile acid excretion in feces (p < 0.05). Conclusion: WG did not significantly increase bile acid excretion in feces or decrease serum levels of total cholesterol. Moreover, WGP and WG both presented significant antioxidant activity in vivo (p < 0.05) and caused a significant reduction in cholesterol micellar solubility in vitro (p < 0.001). Therefore, WGP may effectively prevent hyperlipidemia and its complications as WGP treatment enhanced antioxidant activity, decreased the concentration of serum lipids and improved the activity of enzymes involved in cholesterol metabolism.
Discovery of Novel Epoxyketone Peptides as Lipase Inhibitors
Authors: Almaliti Jehad , Alzweiri Muhammed , Alhindy Momen , Al-Helo Tamam , Daoud Ibrahim , Deknash Raghad , Naman C. Benjamin , Abu-Irmaileh Bashaer , Bustanji Yasser , Hamad Islam
Published: April 2022

Obesity is the most common nutritional disorder in the developed world and is associated with important comorbidities. Pancreatic lipase (PL) inhibitors play a key role in the metabolism of human fat. A series of novel epoxyketones peptide derivatives were investigated for their pancreatic lipase inhibitory activity. The epoxyketone moiety is a well-known reactive electrophile group that has been used as part of proteasome inhibitors in cancer therapy, and it is widely believed that these are very selective for targeting the proteasome active site. Here we investigated various peptide derivatives with an epoxide warhead for their anti-lipase activity. The assessment of these novel epoxyketones was performed by an in-house method that we developed for rapid screening and identification of lipase inhibitors using GC-FID. Herein, we present a novel anti-lipase pharmacophore based on epoxyketone peptide derivatives that showed potent anti-lipase activity. Many of these derivatives had comparable or more potent activity than the clinically used lipase inhibitors such as orlistat. In addition, the lipase appears to be inhibited by a wide range of epoxyketone analogues regardless of the configuration of the epoxide in the epoxyketone moiety. The presented data in this study shows the first example of the use of epoxyketone peptides as novel lipase inhibitors.
Identification and Quantification by NMR Spectroscopy of the 22R and 22S Epimers in Budesonide Pharmaceutical Forms
Authors: Kuz’mina Natalia E. , Moiseev Sergey V. , Severinova Elena Y. , Stepanov Evgenii A. , Bunyatyan Natalia D.
Published: April 2022

The authors developed four variants of the qNMR technique (1H or 13C nucleus, DMSO-d6 or CDCl3 solvent) for identification and quantification by NMR of 22R and 22S epimers in budesonide active pharmaceutical ingredient and budesonide drugs (sprays, capsules, tablets). The choice of the qNMR technique version depends on the drug excipients. The correlation of 1H and 13C spectra signals to molecules of different budesonide epimers was carried out on the basis of a comprehensive analysis of experimental spectral NMR data (1H-1H gCOSY, 1H-13C gHSQC, 1H-13C gHMBC, 1H-1H ROESY). This technique makes it possible to identify budesonide epimers and determine their weight ratio directly, without constructing a calibration curve and using any standards. The results of measuring the 22S epimer content by qNMR are comparable with the results of measurements using the reference HPLC method.
An Expeditious Approach towards the Synthesis and Application of Water-Soluble and Photostable Fluorogenic Chromones for DNA Detection
Authors: Vincent Steve , Mallick Suman , Barnoin Guillaume , Le Hoang-Ngoan , Michel Benoît Y. , Burger Alain
Published: April 2022

The intensive research for hybridization probes based on organic molecules with fluorogenic properties is currently attracting particular attention due to their potential to efficiently recognize different DNA conformations and the local environment. However, most established organic chromophores do not meet the requirements of this task, as they do not exhibit good brightness in aqueous buffer media, develop aggregation and/or are not easily conjugated to oligodeoxynucleotides (ODNs) while keeping their photophysics intact. Herein, an important modification strategy was employed for a well-known fluorophore, 2-(4-(diethylamino)phenyl)-3-hydroxychromone (dEAF). Although this push–pull dye absorbs intensively in the visible range and shows emission with large Stokes shifts in all organic solvents, it is strongly quenched in water. This Achilles’ heel prompted us to implement a new strategy to obtain a series of dyes that retain all the photophysical features of dEAF in water, conjugate readily with oligonucleotides, and furthermore demonstrate sensitivity to hydration, thus paving the way for a high-performance fluorogenic DNA hybridization probe.
Impact of Chitosan on the Mechanical Stability of Soils
Authors: Adamczuk Agnieszka , Jozefaciuk Grzegorz
Published: April 2022

Chitosan is becoming increasingly applied in agriculture, mostly as a powder, however little is known about its effect on soil mechanical properties. Uniaxial compression test was performed for cylindrical soil aggregates prepared from four soils of various properties (very acidic Podzol, acidic Arenosol, neutral Fluvisol and alkaline Umbrisol) containing different proportions of two kinds of chitosan (CS1 of higher molecular mass and lower deacetylation degree, and CS2 of lower molecular mass and higher deacetylation degree), pretreated with 1 and 10 wetting–drying cycles. In most cases increasing chitosan rates successively decreased the mechanical stability of soils that was accompanied by a tendential increase in soil porosity. In one case (Fluvisol treated with CS2) the porosity decreased and mechanical stability increased with increasing chitosan dose. The behavior of acidic soils (Podzol and Arenosol) treated with CS2, differed from the other soils: after an initial decrease, the strength of aggregates increased with increasing chitosan amendment, despite the porosity consequently decreasing. After 10 wetting–drying cycles, the strength of the aggregates of acidic soils appeared to increase while it decreased for neutral and alkaline soils. Possible mechanisms of soil–chitosan interactions affecting mechanical strength are discussed and linked with soil water stability and wettability.
Phytotherapeutic Approaches to the Prevention of Age-Related Changes and the Extension of Active Longevity
Authors: Babich Olga , Larina Viktoria , Ivanova Svetlana , Tarasov Andrei , Povydysh Maria , Orlova Anastasiya , Strugar Jovana , Sukhikh Stanislav
Published: April 2022

Maintaining quality of life with an increase in life expectancy is considered one of the global problems of our time. This review explores the possibility of using natural plant compounds with antioxidant, anti-inflammatory, anti-glycation, and anti-neurodegenerative properties to slow down the onset of age-related changes. Age-related changes such as a decrease in mental abilities, the development of inflammatory processes, and increased risk of developing type 2 diabetes have a significant impact on maintaining quality of life. Herbal preparations can play an essential role in preventing and treating neurodegenerative diseases that accompany age-related changes, including Alzheimer’s and Parkinson’s diseases. Medicinal plants have known sedative, muscle relaxant, neuroprotective, nootropic, and antiparkinsonian properties. The secondary metabolites, mainly polyphenolic compounds, are valuable substances for the development of new anti-inflammatory and hypoglycemic agents. Understanding how mixtures of plants and their biologically active substances work together to achieve a specific biological effect can help develop targeted drugs to prevent diseases associated with aging and age-related changes. Understanding the mechanisms of the biological activity of plant complexes and mixtures determines the prospects for using metabolomic and biochemical methods to prolong active longevity.
Gating Mechanism of the Voltage-Gated Proton Channel Studied by Molecular Dynamics Simulations
Authors: Phan Thi Tuong Vy , Yi Myunggi
Published: April 2022

The voltage-gated proton channel Hv1 has important roles in proton extrusion, pH homeostasis, sperm motility, and cancer progression. The Hv1 channel has also been found to be highly expressed in cell lines and tissue samples from patients with breast cancer. A high-resolution closed-state structure has been reported for the mouse Hv1 chimera channel (mHv1cc), solved by X-ray crystallography, but the open-state structure of Hv1 has not been solved. Since Hv1 is a promising drug target, various groups have proposed open conformations by molecular modeling and simulation studies. However, the gating mechanism and the open-state conformation under the membrane potential are still debate. Here, we present a molecular dynamics study considering membrane potential and pH conditions. The closed-state structure of mHv1cc was used to run molecular dynamics (MD) simulations with respect to electric field and pH conditions in order to investigate the mechanism of proton transfer. We observed a continuous hydrogen bond chain of water molecules called a water-wire to be formed through the channel pore in the channel opening, triggered by downward displacement of the S2 helix and upward movement of the S4 helix relative to other helices. Due to the movement of the S2 and S4 helices, the internal salt bridge network was rearranged, and the hydrophobic gating layers were destroyed. In line with previous experimental and simulation observations, our simulation results led us to propose a new gating mechanism for the Hv1 proton channel, and may provide valuable information for novel drug discovery.
Development of Bicyclo[3.1.0]hexane-Based A3 Receptor Ligands: Closing the Gaps in the Structure–Affinity Relationships
Authors: Lemmerhirt Jan Phillip , Isaak Andreas , Liu Rongfang , Kock Max , Daniliuc Constantin G. , Jacobson Kenneth A. , Heitman Laura H. , Junker Anna
Published: April 2022

The adenosine A3 receptor is a promising target for treating and diagnosing inflammation and cancer. In this paper, a series of bicyclo[3.1.0]hexane-based nucleosides was synthesized and evaluated for their P1 receptor affinities in radioligand binding studies. The study focused on modifications at 1-, 2-, and 6-positions of the purine ring and variations of the 5′-position at the bicyclo[3.1.0]hexane moiety, closing existing gaps in the structure–affinity relationships. The most potent derivative 30 displayed moderate A3AR affinity (Ki of 0.38 μM) and high A3R selectivity. A subset of compounds varied at 5′-position was further evaluated in functional P2Y1R assays, displaying no off-target activity.
Evaluating Tannins and Flavonoids from Traditionally Used Medicinal Plants with Biofilm Inhibitory Effects against MRGN E. coli
Authors: Neumann Niclas , Honke Miriam , Povydysh Maria , Guenther Sebastian , Schulze Christian
Published: April 2022

In the search for alternative treatment options for infections with multi-resistant germs, traditionally used medicinal plants are currently being examined more intensively. In this study, the antimicrobial and anti-biofilm activities of 14 herbal drugs were investigated. Nine of the tested drugs were traditionally used in Europe for treatment of local infections. For comparison, another five drugs monographed in the European Pharmacopoeia were used. Additionally, the total tannin and flavonoid contents of all tested drugs were analyzed. HPLC fingerprints were recorded to obtain further insights into the components of the extracts. The aim of the study was to identify herbal drugs that might be useable for treatment of infectious diseases, even with multidrug resistant E. coli, and to correlate the antimicrobial activity with the total content of tannins and flavonoids. The agar diffusion test and anti-biofilm assay were used to evaluate the antimicrobial potential of different extracts from the plants. Colorimetric methods (from European Pharmacopeia) were used for determination of total tannins and flavonoids. The direct antimicrobial activity of most of the tested extracts was low to moderate. The anti-biofilm activity was found to be down to 10 µg mL−1 for some extracts. Tannin contents between 2.2% and 10.4% of dry weight and total flavonoid contents between 0.1% and 1.6% were found. Correlation analysis indicates that the antimicrobial and the anti-biofilm activity is significantly (p < 0.05) dependent on tannin content, but not on flavonoid content. The data analysis revealed that tannin-rich herbal drugs inhibit pathogens in different ways. Thus, some of the tested herbal drugs might be useable for local infections with multi-resistant biofilm-forming pathogens. For some of the tested drugs, this is the first report about anti-biofilm activity, as well as total tannin and flavonoid content.
A Review on Regenerating Materials from Spent Lithium-Ion Batteries
Authors: Xu Rui , Xu Wei , Wang Jinggang , Liu Fengmei , Sun Wei , Yang Yue
Published: April 2022

Recycling spent lithium-ion batteries (LIBs) have attracted increasing attention for their great significance in environmental protection and cyclic resources utilization. Numerous studies focus on developing technologies for the treatment of spent LIBs. Among them, the regeneration of functional materials from spent LIBs has received great attention due to its short process route and high value-added product. This paper briefly summarizes the current status of spent LIBs recycling and details the existing processes and technologies for preparing various materials from spent LIBs. In addition, the benefits of material preparation from spent LIBs, compared with metals recovery only, are analyzed from both environmental and economic aspects. Lastly, the existing challenges and suggestions for the regeneration process are proposed.
Anti-Influenza Virus Study of Composite Material with MIL-101(Fe)-Adsorbed Favipiravir
Authors: Xu Mengyuan , Li Xi , Zheng Huiying , Chen Jiehan , Ye Xiaohua , Liu Tiantian
Published: April 2022

Nanomaterial technology has attracted much attention because of its antibacterial and drug delivery properties, among other applications. Metal-organic frameworks (MOFs) have advantages, such as their pore structure, large specific surface area, open metal sites, and chemical stability, over other nanomaterials, enabling better drug encapsulation and adsorption. In two examples, we used the common pathogenic bacterium Staphylococcus aureus and highly infectious influenza A virus. A novel complex MIL-101(Fe)-T705 was formed by synthesizing MOF material MIL-101(Fe) with the drug favipiravir (T-705), and a hot solvent synthesis method was applied to investigate the in vitro antibacterial and antiviral activities. The results showed that MIL-101(Fe)-T705 combined the advantages of nanomaterials and drugs and could inhibit the growth of Staphylococcus aureus at a concentration of 0.0032 g/mL. Regarding the inhibition of influenza A virus, MIL-101(Fe)-T705 showed good biosafety at 12, 24, 48, and 72 h in addition to a good antiviral effect at concentrations of 0.1, 0.2, 0.4, 0.8, 1.6, and 3 μg/mL, which were higher than MIL-101(Fe) and T-705.
Characteristics of New England India Pale Ale Beer Produced with the Use of Norwegian KVEIK Yeast
Authors: Kawa-Rygielska Joanna , Adamenko Kinga , Pietrzak Witold , Paszkot Justyna , Głowacki Adam , Gasiński Alan
Published: April 2022

The aim of this research was to determine the potential of four unconventional Norwegian yeasts of the KVEIK type to produce NEIPA beer. The influence of yeast strains on fermentation process, physicochemical properties, antioxidant potential, volatile compounds, and sensory properties was investigated. The KVEIK-fermented beer did not differ in terms of physicochemical parameters from the beer produced with the commercial variants of US-05 yeast. The yeast strain influenced the sensory quality (taste and aroma) of the beers, with KVEIK-fermented beer rating significantly higher. The antioxidant activity of the tested beers also significantly depended on the yeast strain applied. The beers fermented with KVEIK had a significantly higher antioxidant potential (ABTS•+) than those fermented with US-05. The strongest antioxidant activity was found in the beer brewed with the Lida KVEIK yeast. The use of KVEIK to produce NEIPA beer allowed enrichment of the finished products with volatile compounds isobutanol, 2-pentanol, 3-methylobutanol, ethyl octanoate, and ethyl decanoate.
Microporous N-Doped Carbon Obtained from Salt Melt Pyrolysis of Chitosan toward Supercapacitor and Oxygen Reduction Catalysts
Authors: Rybarczyk Maria Krystyna , Cysewska Karolina , Yuksel Recep , Lieder Marek
Published: April 2022

The direct carbonization of low-cost and abundant chitosan biopolymer in the presence of salt eutectics leads to highly microporous, N-doped nanostructures. The microporous structure is easily manufactured using eutectic mixture (ZnCl2-KCl) and chitosan. Potassium ions here can act as an intercalating agent, leading to the formation of lamellar carbon sheets, whereas zinc chloride generates significant porosity. Here, we present an efficient synthetic way for microporous carbon nanostructures production with a total nitrogen content of 8.7%. Preliminary studies were performed to show the possibility of the use of such material as a catalyst for supercapacitor and ORR. The textural properties enhanced capacitance, which stem from improved accessibility of previously blocked or inactive pores in the carbon structure, leading to the conclusion that porogen salts and molten salt strategies produce materials with tailor-made morphologies. The synergistic effect of the eutectic salt is seen in controlled porous structures and pore size, and the micropores boosting adsorption ability.
Changes in Number and Antibacterial Activity of Silver Nanoparticles on the Surface of Suture Materials during Cyclic Freezing
Authors: Basov Alexander , Dzhimak Stepan , Sokolov Mikhail , Malyshko Vadim , Moiseev Arkadii , Butina Elena , Elkina Anna , Baryshev Mikhail
Published: April 2022

This article presents the results of the 10-fold cyclic freezing (−37.0 °C) and thawing (0.0 °C) effect on the number and size range of silver nanoparticles (AgNPs). AgNPs were obtained by the cavitation-diffusion photochemical reduction method and their sorption on the fiber surface of various suture materials, perlon, silk, and catgut, was studied. The distribution of nanoparticles of different diameters before and after the application of the cyclic freezing/thawing processes for each type of fibers studied was determined using electron microscopy. In general, the present study demonstrates the effectiveness of using the technique of 10-fold cyclic freezing. It is applicable to increase the absolute amount of AgNPs on the surface of the suture material with a simultaneous decrease in the size dispersion. It was also found that the application of the developed technique leads to the overwhelming predominance of nanoparticles with 1 to 15 nm diameter on all the investigated fibers. In addition, it was shown that after the application of the freeze/thaw method, the antibacterial activity of silk and catgut suture materials with AgNPs was significantly higher than before their treatment by cyclic freezing.
The Effect of Acute Caffeine Ingestion on Tactical Performance of Professional Soccer Players
Authors: de Almeida Rodrigo Freire , da Costa Israel Teoldo , Machado Guilherme , Rinaldi Natalia Madalena , Aquino Rodrigo , Tallis Jason , Clarke Neil David , Guimaraes-Ferreira Lucas
Published: April 2022

In soccer, physical, tactical, and decision-making processes are highly important facets of successful performance. Caffeine has well established effects for promoting both physical and cognitive performance, but the translation of such benefits specifically for soccer match play is not well established. This study examined the effects of acute caffeine ingestion on tactical performance during small-sided games (SSG) in professional soccer players. Nineteen soccer players (22 ± 4 years) underwent a randomized, counterbalanced, crossover, double-blind placebo-controlled trial. The protocol consisted of 5 bouts of 5-min SSG with 3 players plus a goalkeeper in each team (3 + GK × 3 + GK) with each SSG separated by 1 min rest intervals. Tactical performance was assessed using the system of tactical assessment in soccer (FUT-SAT). Prior to each experimental trial, participants ingested caffeine (5 mg·kg−1) or a placebo 60 min before the protocol. Overall, caffeine ingestion resulted in an increased ball possession time when compared to the placebo. When the offensive and defensive core principles were analyzed, the results were equivocal. Caffeine resulted in positive effects on some tactical decisions during the protocol, but it was deleterious or promoted no observed effect on other of the core tactical principles. Caffeine ingestion resulted in less offensive (during SSG3) and defensive (SSG 2, SSG3, and SSG4) errors. Caffeine ingestion also resulted in higher total offensive success during SSG 1 and SSG2, but it was detrimental during SSG3. Additionally, total defensive success was lower for the caffeine conditions during SSG 2 and SSG5 when compared to the placebo. In conclusion, caffeine influenced aspects of tactical decisions in soccer, resulting in fewer offensive and defensive errors, although it may be deleterious considering other tactical parameters. Future studies may clarify the effects of caffeine ingestion on specific decision-making parameters in soccer.
Food Contamination: An Unexplored Possible Link between Dietary Habits and Parkinson’s Disease
Authors: Caioni Giulia , Cimini Annamaria , Benedetti Elisabetta
Published: April 2022

Importance of a healthy lifestyle in maintaining the population’s well-being and health, especially in terms of balanced nutrition, is well known. Food choice of and dieting habits could impact disease management, which is especially true for Parkinson’s disease (PD). However, nowadays, it is not that simple to maintain a balance in nutrition, and the idea of a healthy diet tends to fade as the consequence of a western lifestyle. This should not only be dealt with in the context of food choice, but also from an environmental point of view. What we put into our bodies is strictly related to the quality of ecosystems we live in. For these reasons, attention should be directed to all the pollutants, which in many cases, we unknowingly ingest. It will be necessary to explore the interaction between food and environment, since human activity also influences the raw materials destined for consumption. This awareness can be achieved by means of an innovative scientific approach, which involves the use of new models, in order to overcome the traditional scientific investigations included in the study of Parkinson’s disease.
Dual-Labelling Strategies for Nuclear and Fluorescence Molecular Imaging: Current Status and Future Perspectives
Authors: Kubeil Manja , Martínez Irma , Bachmann Michael , Kopka Klaus , Tuck Kellie , Stephan Holger
Published: April 2022

Molecular imaging offers the possibility to investigate biological and biochemical processes non-invasively and to obtain information on both anatomy and dysfunctions. Based on the data obtained, a fundamental understanding of various disease processes can be derived and treatment strategies can be planned. In this context, methods that combine several modalities in one probe are increasingly being used. Due to the comparably high sensitivity and provided complementary information, the combination of nuclear and optical probes has taken on a special significance. In this review article, dual-labelled systems for bimodal nuclear and optical imaging based on both modular ligands and nanomaterials are discussed. Particular attention is paid to radiometal-labelled molecules for single-photon emission computed tomography (SPECT) and positron emission tomography (PET) and metal complexes combined with fluorescent dyes for optical imaging. The clinical potential of such probes, especially for fluorescence-guided surgery, is assessed.
Plectranthus zeylanicus: A Rich Source of Secondary Metabolites with Antimicrobial, Disinfectant and Anti-Inflammatory Activities
Authors: Napagoda Mayuri , Gerstmeier Jana , Butschek Hannah , Lorenz Sybille , De Soyza Sudhara , Qader Mallique , Nagahawatte Ajith , Wijayaratne Gaya Bandara , Schneider Bernd , Svatoš Aleš , Jayasinghe Lalith , Koeberle Andreas , Werz Oliver
Published: April 2022

Plectranthus zeylanicus Benth is used in Sri Lankan folk medicine as a remedy for inflammatory conditions and microbial infections. Our previous investigations revealed potent 5-lipoxygenase (5-LO) inhibitory activity in lipophilic extracts of this plant, supporting its anti-inflammatory potential. In-depth studies on the antimicrobial activity have not been conducted and the bioactive ingredients remained elusive. As a continuation of our previous work, the present investigation was undertaken to evaluate the antimicrobial activity of different extracts of P. zeylanicus and to isolate and characterize bioactive secondary metabolites. Different organic extracts of this plant were analyzed for their antibacterial activity, and the most active extract, i.e., dichloromethane extract, was subjected to bioactivity-guided fractionation, which led to the isolation of 7α-acetoxy-6β-hydroxyroyleanone. This compound displayed strong antibacterial activity against methicillin-resistant Staphylococcus aureus with a minimum inhibitory concentration of 62.5 µg/mL, and its disinfectant capacity was comparable to the potency of a commercial disinfectant. Moreover, 7α-acetoxy-6β-hydroxyroyleanone inhibits 5-LO with IC50 values of 1.3 and 5.1 µg/mL in cell-free and cell-based assays, respectively. These findings rationalize the ethnopharmacological use of P. zeylanicus as antimicrobial and anti-inflammatory remedy.
Large Scale Hydrodynamically Coupled Brownian Dynamics Simulations of Polymer Solutions Flowing through Porous Media
Authors: Ahuja Vishal Raju , van der Gucht Jasper , Briels Wim
Published: April 2022

Large scale simulations of polymer flow through porous media provide an important tool for solving problems in enhanced oil recovery, polymer processing and biological applications. In order to include the effects of a wide range of velocity and density fluctuations, we base our work on a coarse-grain particle-based model consisting of polymers following Brownian dynamics coupled to a background fluid flow through momentum conserving interactions. The polymers are represented as Finitely Extensible Non-Linear Elastic (FENE) dumbbells with interactions including slowly decaying transient forces to properly describe dynamic effects of the eliminated degrees of freedom. Model porous media are constructed from arrays of parallel solid beams with circular or square cross-sections, arranged periodically in the plane perpendicular to their axis. No-slip boundary conditions at the solid–fluid interfaces are imposed through interactions with artificial particles embedded within the solid part of the system. We compare the results of our simulations with those of standard Smoothed Particle Hydrodynamics simulations for Newtonian flow through the same porous media. We observe that in all cases the concentration of polymers at steady state is not uniform even though we start the simulations with a uniform polymer concentration, which is indicative of shear-induced cross-flow migration. Furthermore, we see the characteristic flattening of the velocity profile experimentally observed for shear-thinning polymer solutions flowing through channels as opposed to the parabolic Poiseuille flow profile for Newtonian fluids.
Study on Microwave Absorption Performance Enhancement of Metamaterial/Honeycomb Sandwich Composites in the Low Frequency Band
Authors: Li Songming , Huang Hao , Wu Sibao , Wang Jiafu , Lu Haijun , Xing Liying
Published: April 2022

With the rapid development of electronic technology and modern radar detection system, there is increasingly urgent demand for microwave absorbing composites working efficiently in the low frequency range (e.g., 1–2 GHz). In this work, a type of metamaterial/honeycomb sandwich composite (MHSC) was proposed and fabricated, which exhibited a light weight structure and excellent wave-absorbing performance in the low frequency band. The relationship between the wave-absorbing properties and the design parameters of the composite, such as the thickness of the wave-transmitting skin, the thickness and dielectric properties of the wave-absorbing honeycomb, was systematically investigated. The electromagnetic coupling interference between the honeycomb absorber and metamaterial resonator proved to be a crucial factor that affects synergistic wave-absorbing performance in the low-frequency band. Under the rational design, the incorporation of subwavelength-sized phase-gradient metamaterial units in the composite can significantly improve low-frequency wave-absorbing performance for greater than 5 dB (an increment larger than 100%); and the obtained MHSC exhibits averaged reflectivity (Ra) less than −10 dB in the low frequency band of 1–2 GHz as well as outstanding performance (Ra < −14.6 dB) over an extremely wide frequency range (1–18 GHz). The MHSC reported in this study could be a promising candidate for the key material in high-performance radar stealth and other related applications.