High Load Research Articles

Experimental study on impact behaviour of normal strength mortar at cryogenic temperatures and after freeze-thaw cycles

Concrete structures employed for the storage of Liquefied Natural Gases (LNG) currently undergo temperature as low as −170 °C. These critical engineering structures may also experience dynamic loads such as impact or explosion during service life. Therefore, it is crucial to explore the mechanical response of concrete at intermediate to high strain rates together with low temperatures or cryogenic freeze-thaw (FT) cycles. This study presents experimental research into the combined effects of low temperatures and strain rate on normal strength mortar, providing a preliminary analysis of the dynamic performance of concrete at low and cryogenic temperatures. A Split Hopkinson Pressure Bar (SHPB) device was used to investigate the characteristics of dynamic compression (at strain rates of 40, 80, 120 and 160 s−1) and dynamic split tension (at strain rates of 20, 40, 60 and 80 s−1) of Normal Strength Mortar (NSM) at different low temperatures. In addition, the dynamic compression (at strain rates of 80, 130 and 180 s−1) after cryogenic FT cycles was also explored. The findings revealed that the failure pattern of NSM samples exposed to coupled low temperature or cryogenic FT cycles and high strain rate loading notably varied from that observed under room temperature condition. Both the dynamic compressive and split tensile strengths of NSM increased with the strain rates at all temperatures. At −160 °C, the dynamic compressive and splitting tensile strengths of NSM specimens were greater than those at room temperature (by 10.94 % and 28.29 %, respectively) and −70 °C (by 3.13 % and 4.12 %, respectively). Cryogenic freeze-thaw cycles evidently impacted the material static and dynamic performance. An empirical model was developed to predict the dynamic increase factors (DIFs) for both dynamic compression and splitting tensile strengths of NSM at low/cryogenic temperatures and after freeze-thaw cycles. Scanning electron microscopy (SEM) technique was performed to study and comprehend the microscopic processes and microstructural changes after FT cycles.

Hybrid Mn Atomic Clusters/Single-Dispersed Atoms with Dual Antioxidant Activities for a Chemiluminescent Immunoassay.

Single-dispersed atoms (SDAs) as catalysts have drawn extensive attention due to their ultimate atom utilization efficiency and desirable catalytic capability. Atomic clusters (ACs) with potential multiple enzyme-like activities also display great practicability in catalysis-based biosensing. In this work, hybrid Mn ACs/SDAs were implanted in the frameworks of defect-engineered MIL 101(Cr) modulated by excess acetic acid, with a high loading capability of 13.9 wt %. Distinctively, Mn SDAs display weak superoxide dismutase (SOD)-like activity for specifically eliminating superoxide anion (O2•-), while Mn ACs/SDAs display both catalase-like and SOD-like activities for remarkable elimination of total reactive oxygen species (ROS) due to the cooperative effect of the two atom-scale catalytic sites. Thus, Mn ACs/SDAs can efficiently inhibit the chemiluminescent (CL) emission of multiple ROS-mediated luminol systems with a superior quenching rate of 85.5%. To validate the practicability of Mn ACs/SDAs for a sensitive CL assay, an immunoassay method was established to detect acetamiprid by using Mn ACs/SDAs as signal quenchers, which displayed a quantification range of 10 pg mL-1-25 ng mL-1 and a detection limit of 3.3 pg mL-1. This study paves an avenue for developing ACs/SDAs with multiple antioxidant activities that are suitable for application in biosensing.

Modulation of alpha oscillations by attention is predicted by hemispheric asymmetry of subcortical regions.

Evidence suggests that subcortical structures play a role in high-level cognitive functions such as the allocation of spatial attention. While there is abundant evidence in humans for posterior alpha band oscillations being modulated by spatial attention, little is known about how subcortical regions contribute to these oscillatory modulations, particularly under varying conditions of cognitive challenge. In this study, we combined MEG and structural MRI data to investigate the role of subcortical structures in controlling the allocation of attentional resources by employing a cued spatial attention paradigm with varying levels of perceptual load. We asked whether hemispheric lateralization of volumetric measures of the thalamus and basal ganglia predicted the hemispheric modulation of alpha-band power. Lateral asymmetry of the globus pallidus, caudate nucleus, and thalamus predicted attention-related modulations of posterior alpha oscillations. When the perceptual load was applied to the target and the distractor was salient caudate nucleus asymmetry predicted alpha-band modulations. Globus pallidus was predictive of alpha-band modulations when either the target had a high load, or the distractor was salient, but not both. Finally, the asymmetry of the thalamus predicted alpha band modulation when neither component of the task was perceptually demanding. In addition to delivering new insight into the subcortical circuity controlling alpha oscillations with spatial attention, our finding might also have clinical applications. We provide a framework that could be followed for detecting how structural changes in subcortical regions that are associated with neurological disorders can be reflected in the modulation of oscillatory brain activity.

Cultivation of a naturally resilient Chlorella sp.: A bioenergetic strategy for valorization of cheese whey for high nutritional biomass production

This study investigated Chlorella's capacity to treat cheese whey (CW) effluent and produce a high-nutritional value biomass, by using a systematic sequential experimental design. Physicochemical analysis of CW revealed its high pollution load, characterized by elevated levels of lactose, phosphorus, and nitrogen, as well as high turbidity due to the presence of whey solids. Screening experiments demonstrated that trace mineral addition and continuous air supply are essential factors for Chlorella biomass production in CW (>800 mg·mL−1). Furthermore, whey solids did not hinder Chlorella growth, with notable biomass production observed even in undiluted CW, demonstrating this microalga's ability to adapt metabolically to the complex environment. Laboratory-scale photobioreactor experiments confirmed Chlorella's ability to produce biomass in CW, outperforming controls (>800 mg·mL−1). Bioremediation potential assessment exhibited significant reductions in organic pollutants (>14 g·L−1 COD), nitrogen (>400 mg·L−1), phosphorus (>140 mg·L−1) and sodium (>650 mg·L−1). CW solids were also removed with Chlorella harvesting (>99 %). Harvested algal biomass was enriched with proteins (>40 g·100 g−1), polyunsaturated fatty acids (>9 % TFA) and pigments, offering potential applications in nutraceutical and pharmaceutical industries. Overall, this study highlights Chlorella's efficacy in CW treatment and biomass valorization, offering a sustainable solution for dairy wastewater management while producing valuable resources.

An Electrolyte Engineered Homonuclear Copper Complex as Homogeneous Catalyst for Lithium-Sulfur Batteries.

Lithium-sulfur (Li-S) batteries suffer from severe polysulfide shuttle, retarded sulfur conversion kinetics and notorious lithium dendrites, which has curtailed the discharge capacity, cycling lifespan and safety. Engineered catalysts act as a feasible strategy to synchronously manipulate the evolution behaviors of sulfur and lithium species. Herein, a chlorine bridge-enabled binuclear copper complex (Cu-2-T) is in situ synthesized in electrolyte as homogeneous catalyst for rationalizing the Li-S redox reactions. The well-designed Cu-2-T provides completely active sites and sufficient contact for homogeneously guiding the Li2S nucleation/decomposition reactions, and stabilizing the lithium working interface according to the synchrotron radiation X-ray 3D nano-computed tomography, small angle neutron scattering and COMSOL results. Moreover, Cu-2-T with the content of 0.25wt% approaching saturated concentration in electrolyte further boosts the homogeneous optimization function in really operated Li-S batteries. Accordingly, the capacity retention of the Li-S battery is elevated from 51.4% to 86.3% at 0.2 C, and reaches 77.0% at 1.0 C over 400 cycles. Furthermore, the sulfur cathode with the assistance of Cu-2-T realizes the stable cycling under the practical scenarios of soft-packaged pouch cell and high sulfur loading (6.5mg cm-2 with the electrolyte usage of 4.5µL mgS -1).

Oil-loaded Mesoporous Silica to Enhance the Lubrication of Polypropylene Resin Composite Materials

Polymer self-lubricating materials have advantages such as low friction coefficient, good wear resistance, and high work efficiency, giving them wide application potential in friction and wear. This work fabricated polymer-based self-lubricating materials by incorporating oil-loaded mesoporous silica nanoparticles (MSNs + YR1800) in the polypropylene resin (PP). The effectsof different content of MSNs + YR1800 on the tribological and mechanicalof the obtained self-lubricating composite materials were studied. The results indicate that the content of MSNs + YR1800 in composite materials significantly impacts their tribological properties.When the content of MSNs + YR1800is 10 wt%, the coefficientof friction reduced to 0.09,which was 84.5% lower than PP and 78.6% lower than composite materials containing 5wt% mesoporous silica nanoparticle (MSNs).Compared with pure PP, the wear rate decreases from 4.93 × 10-11 m3*Nm-1 to 4.43 × 10-13 m3*Nm-1, which can be reduced by two orders of magnitude.The excellent tribological properties of composite materials are attributed to the high specific surface area, large pore volume, strong adsorption capacity, and high oil loading capacity of mesoporous silica nanoparticle as nanofillers. The MSNs + YR1800 release lubricants to form a lubricating oil film during the friction process under load conditions, preventing direct contact between the friction pair and the surface of the composite material. Compared with polymer-silica hybrid oil-loaded microcapsules, MSNs + YR1800 can effectively reduce lubricant leakage, prolong operation life, improve lubrication efficiency, and ensure the continuous and stable existence of lubricating oil films.

Modeling the Structure of Ketoprofen-Poly(vinylpyrrolidone) Amorphous Solid Dispersions with Empirical Potential Structure Refinements of X-ray Scattering Data.

The metastability of amorphous formulations poses barriers to their safe and widespread commercialization. The propensity of amorphous solid dispersions (ASDs) to crystallize is directly linked to their molecular structure. Amorphous structures are inherently complex and thus difficult to fully characterize by experiments, which makes structural simulations an attractive route for investigating which structural characteristics correlate with ASD stability. In this study, we use empirical potential structure refinement (EPSR) to create molecular models of ketoprofen-poly(vinylpyrrolidone) (KTP/PVP) ASDs with 0-75 wt % drug loading. The EPSR technique uses X-ray total scattering measurements as constraints, yielding models that are consistent with the X-ray data. We perform several simulations to assess the sensitivity of the EPSR approach to input parameters such as intramolecular bond rotations, PVP molecule length, and PVP tacticity. Even at low drug loading (25 wt %), ∼40% of KTP molecules participate in KTP-KTP hydrogen bonding. The extent of KTP-PVP hydrogen bonding does not decrease significantly at higher drug loadings. However, the models' relative uncertainties are too large to conclude whether ASDs' lower stabilities at high drug loadings are due to changes in drug-excipient hydrogen bonding or a decrease in steric hindrance of KTP molecules. This study illustrates how EPSR, combined with total scattering measurements, can be a powerful tool for investigating structural characteristics in amorphous formulations and developing ASDs with improved stability.

Hierarchical Silica Composites for Enhanced Water Adsorption at Low Humidity.

To combat water scarcity in remote areas around the world, adsorption-based atmospheric water harvesting (AWH) has been proposed as a technology that can be used alongside existing water production capabilities. However, commonly used adsorbents either have low water adsorption loadings or are difficult to regenerate. In this work, we developed two novel hierarchical silica-salt composites that both exhibit high water adsorption loadings under dry and humid conditions. The total water vapor loading, kinetics, and heats of water adsorption for both silica-salt composites were investigated. As hierarchical silicas have tunable pores and large pore volumes, these materials serve as effective host matrixes for the hygroscopic salt LiCl. Our results suggest that hierarchical pores play a significant role in water adsorption: micropores and some smaller mesopores act as "storage" sites for hygroscopic salt, whereas larger mesopores and macropores increase the accessibility of water vapor into the silica. Using this mix of pores, we achieved greater than 0.4 g H2O/g composite at 10% RH and 27 °C. Additionally, we found that the salt-impregnated silica and bare silica had the same heat of adsorption: 80-90 kJ/mol. The results suggest that the H-bond interactions are similar for both systems and that the primary mechanism at play here is water cluster adsorption/desorption. Despite the similar energies, the LiCl-containing materials exhibited considerably slower kinetics than bare silica materials. Of equal importance to the adsorption capacity and kinetics of these composites is their mechanical stability. To assess their mechanical stability, high-energy ball milling of silica was conducted to create more uniform particle sizes. However, reduced particle sizes came at a cost─the BET surface areas and pore volumes were drastically decreased after more than 1 h of ball milling. Findings from this study suggest that short-term ball milling may be a viable large-scale option to reduce particle size in silica materials without sacrificing significant performance.

Elucidating the role of organic loading rate on the performance and microbial dynamics of a novel continuous-flow aerobic granular sludge reactor

Aerobic granular sludge technology operated in continuous-flow reactors enables the upgrading of existing conventional wastewater treatment plants. The viability of applying this technology at full-scale increases with the simplicity of the bioreactor design. Hence, in contrast to previous research carried out in complex configurations, this study is based on evaluating the capacity of a novel single-chamber continuous-flow bioreactor to operate at different loads found in domestic sewage, highlighting that this configuration combines and joins the advantages of activated sludge and granular sludge technologies. At organic loading rates ranging from 0.45 to 1.85 kg COD•m−3•d−1, the reactors achieved high performance, removing >80 % of the chemical oxygen demand, regardless influent characteristics. The trend of ammonium removal rates was risen over operational time. Moreover, the granular size and biomass concentration increased with the organic loading rate. Changes in the influent did not compromise the structure of the granules. Microbiota studies showed a high diversity in communities at lower organic loading rates, whereas a strong microbial competition was detected at high loading rates, linking with lower evenness. Phylotypes belonging to Hypocreales played a key role in mature granules.

Statistical analysis of water quality change by total maximum daily load policy stage

This study aimed to derive major pollutants for standard watersheds with relatively high pollution levels and identify their trends. Hence, the water quality index (WQI) and multivariate statistical techniques were used to analyze the water quality evaluation of standard watershed during the total maximum daily load (TMDL) policy period implemented since 2004. The WQI was calculated for 41 standard watersheds, divided into 14 main streams and 27 tributaries. Consequently, in the main stream, WQI decreased as it moved downstream after the MS5 site. In the tributary, WQI values were found to be low at TS11, TS15, TS16, and TS17 sites. However, the Mann–Kendall test results indicated that the overall WQI value was increasing, suggesting that the water quality of the study basin was improving as the TMDL policy phase progressed. Principal component analysis of the group with relatively low WQI among the standard watersheds revealed that water temperature, dissolved oxygen, total phosphorus, chemical oxygen demand, biochemical oxygen demand, and electrical conductivity were the main variables in the main stream cluster. In the tributary stream cluster, total phosphorus, dissolved oxygen, total suspended solids, total nitrogen, and electrical conductivity showed high loading values. This study proposed a series of methods to provide the basic data required for watershed management through detailed water quality assessment methods, statistical techniques for deriving major pollutants, and trend analysis of water quality evaluation.

Nanoencapsulated MgBu2@ZIF-67 to Construct High Loading Mg-Co@C Nanocomposites: Breaking Through the Barrier of Room Temperature Onset Dehydrogenation.

The synergies of nanoconfinement and catalysis is an effective strategy to improve the kinetic and thermodynamic properties of Mg-based materials. However, obtaining Mg-based materials with high loading, anti-aggregation, and containing nanocatalysts to achieve dehydrogenation at room temperature remains a huge challenge. Herein, a novel and universal preparation strategy for Mg-Co@C nanocomposites with 9.5nm Mg nanoparticles and 9.4nm Co nanocatalysts embedded in carbon scaffold is reported. The 9.3nm MgBu2 nanosheets precipitated by solvent displacement are encapsulated in ZIF-67 to prepare MgBu2@ZIF-67 precursors, then removing excess MgBu2 on the precursor surface and pyrolysis to obtain Mg-Co@C. It is worth noting that the Mg loading rate of Mg-Co@C is as high as rare 69.7%. Excitingly, the Mg-Co@C begins to dehydrogenate at room temperature with saturate capacity of 5.1wt.%. Meanwhile, its dehydrogenation activation energy (Ea(des) = 68.8kJ mol-1) and enthalpy (ΔH(des) = 61.6kJ mol-1) significantly decrease compared to bulk Mg. First principles calculations indicate that the hydrogen adsorption energy on the Mg2CoH5 surface is only -0.681eV. This work provides a universally applicable novel method for the preparation of nanoscale Mg-based materials with various nanocatalysts added, and provides new ideas for Mg-based materials to achieve room temperature hydrogen storage.

Investigation of the CO2 Activation and Regeneration of Reduced VOx/CeO2 Catalysts Using Multiple In Situ Spectroscopies

Ceria‐supported vanadium oxide (VOx/CeO2) is an important catalyst for various oxidation reactions. Recently, vanadia has emerged again as a less toxic alternative to CrOx‐based catalysts for the CO2‐assisted oxidative dehydrogenation (ODH) of alkanes. To establish a mechanistic understanding of catalyst regeneration during CO2 exposure, often described as the rate‐limiting step of these reactions, we investigated the regeneration of VOx/CeO2 catalysts with different vanadia loadings using multiple in situ spectroscopies, that is, multi‐wavelength Raman, UV‐Vis, IR and X‐ray photoelectron spectroscopy. Time‐dependent analysis reveals that ceria is only partially regenerated in the bulk but fully regenerated in the subsurface. At the surface, stable carbonates form at vacancies, which are able to regenerate the lattice and deactivate ceria surface oxygen. The VOx/CeO2 samples show a loading‐dependent behavior, with low‐loaded samples regenerating vanadia only partially, due to the high concentration of monomers, while at higher loadings, vanadia can be almost fully regenerated due to the higher nuclearities being thermodynamically more stable. Ceria is regenerated faster than vanadia, indicating that vanadia regenerates by oxygen spill‐over from the ceria lattice. Our results provide important mechanistic insight into CO2 activation over supported vanadia catalysts, which is of great relevance for CO2‐assisted ODH reactions.

Flash Joule Heating: A Promising Method for Preparing Heterostructure Catalysts to Inhibit Polysulfide Shuttling in Li-S Batteries.

The "shuttle effect" issue severely hinders the practical application of lithium-sulfur (Li-S) batteries, which is primarily caused by the significant accumulation of lithium polysulfides in the electrolyte. Designing effective catalysts is highly desired for enhancing polysulfide conversion to address the above issue. Here, the one-step flash-Joule-heating route is employed to synthesize a W-W2C heterostructure on the graphene substrate (W-W2C/G) as a catalytic interlayer for this purpose. Theoretical calculations reveal that the work function difference between W (5.08eV) and W2C (6.31eV) induces an internal electric field at the heterostructure interface, accelerating the movement of electrons and ions, thus promoting the sulfur reduction reaction (SRR) process. The high catalytic activity is also confirmed by the reduced activation energy and suppressed polysulfide shuttling by in situ Raman analyses. With the W-W2C/G interlayer, the Li-S batteries exhibit an outstanding rate performance (665 mAh g-1 at 5.0 C) and cycle steadily with a low decay rate of 0.06% over 1000 cycles at a high rate of 3.0 C. Moreover, a high areal capacity of 10.9 mAh cm-2 (1381.4 mAh g-1) is obtained with a high area sulfur loading of 7.9mg cm-2 but a low electrolyte/sulfur ratio of 9.0 µL mg-1.

Evaluation of a football fitness implementation initiative for an older adult population in a small-scale island society

BackgroundThe proportion of older people increases globally, which calls for sustainable interventions promoting healthy aging. Therefore, we aimed to evaluate the potential of Football Fitness as a sustainable model to promote quality of life, mental health, and physical function for older adult.MethodsThe study was conducted in collaboration with a municipality, a football club, and a university, and was designed as a randomized controlled trial. A total of 66 people (34 women, 32 men) older than 60 years were randomly assigned (60/40) to a Football Fitness (FOT) (n = 38, 20 women, 18 men) and a control group (CON) (n = 28, 14 women, 14 men). FOT participated in Football Fitness for 12 weeks. Quality of life (QoL) and mental wellbeing were determined pre-and post-intervention. Physical loading and Flow experience were measured in one representative training session. Blood pressure (BP), Yo–Yo Intermittent endurance test level 1 (Yo–Yo IE1), sprint performance, postural balance, and body composition were also performed pre-and post-intervention.ResultsAn improvement in mental wellbeing was observed for both groups from pre- to post-intervention (p values <0.001) with no between-group differences. Regarding QoL, the environment domain improved in FOT compared to CON (p = 0.02). Mean Flow (M = 5.69; SD = 1.07) and perceived importance (M = 4.20; SD = 1.42) and average experienced difficulty was M = 5.23 (SD = 2.67), perceived skill (M = 5.23; SD = 2.56), and perceived balance (M = 5.64; SD = 1.56). These levels of flow can be characterized as being high. A between-group effect (p = 0.02) existed for systolic BP, which decreased (p < 0.01) by −5% [−8; −1%] in CON and remained unchanged in FOT. Both groups improved the Yo–Yo IE1 to a similar extent, with 28% [11; 44%] (p = 0.001) in FOT and 27% [9; 46%] in CON (p = 0.005). Postural balance improved (p = 0.004) by 38% [13; 63%] in FOT only, resulting in a superior (p = 0.01) balance score in FOT compared to CON post-intervention (p = 0.004).ConclusionFootball Fitness improved the environmental quality of life domain and postural balance in older adults. Additionally, it appears to be a feasible group activity for older adults that promotes high flow and physical loading during training.

Research on identification of flight cadets’ cognitive load based on multi-source physiological data and CGAN-DBN model

Modern aircraft cockpit system is highly information-intensive. Pilots often need to receive a large amount of information and make correct judgments and decisions in a short time. However, cognitive load can affect their ability to perceive, judge and make decisions accurately. Furthermore, the excessive cognitive load will induce incorrect operations and even lead to flight accidents. Accordingly, the research on cognitive load is crucial to reduce errors and even accidents caused by human factors. By using physiological acquisition systems such as eye movement, ECG, and respiration, multi-source physiological signals of flight cadets performing different flight tasks during the flight simulation experiment are obtained. Based on the characteristic indexes extracted from multi-source physiological data, the CGAN-DBN model is established by combining the conditional generative adversarial networks (CGAN) model with the deep belief network (DBN) model to identify the flight cadets’ cognitive load. The research results show that the flight cadets’ cognitive load identification based on the CGAN-DBN model established has high accuracy. And it can effectively identify the cognitive load of flight cadets. The research paper has important practical significance to reduce the flight accidents caused by the high cognitive load of pilots.

Assessment of groundwater fluoride and human health effects in a hard rock province of south India: Implications from Pollution Index Model (PIM) and GeographicalInformationSystem (GIS) techniques.

This research examines whetherthe groundwater in the Sivakasi Region of South India is suitable for consumption, and assesses the possible health hazards for various age demographics including infants, children, teenagers, and adults. A totalof 77 groundwater samples were gathered, covering a total area of 580km2 and analyzed for major and minor ions. The hydrogen ion concentration (pH) of the samples indicates neutral to marginally alkaline. The total dissolved solids (TDS) fluctuate from 255 to 2701mg/l and electrical conductivity varies from 364 to 3540µS/cm. A wide range of fluoride concentration was detected (0.1 to 3.2mg/l) with nearly 38% groundwater samples surpassing the proposed limit (1.5 mg/l) suggestedby the World Health Organization in 2017. Gibbs plot analysis suggested that most of thesamples were influenced by geogenic factors, primarily rock weathering in this region. Correlation analysis showed that most of the samples were impacted by both natural and human sources. The pollution index of groundwater (PIG) fluctuated from 0.67 to 2.60 with approximately 30% and 53% of samples falling into insignificant and low pollution categories, respectively. Furthermore, 10% and 5% of total samples were characterized as moderate and high pollution levels, and 2% asvery high pollution category. Spatial analysis using GIS revealed that 440.63km2 were within safe fluoride levels according to theWHO standards, while 139.32km2 were identified as risk zone. The principal component analysis (PCA1) showedstrong positive loadings on EC (0.994), TDS (0.905), Mg2+ (0.910), Cl- (0.903) and HCO3- (0.923) indicating rock water interaction. PCA2 accounts the high positive factor loading on HCO3- (0.864) indicating ion exchange and mineral leaching. The PCA1 and PCA2 indicated that variables such as mineral leaching and rock water interaction are themajor mechanisms contributing to the chemical signatures in groundwater, which may support for theelevated fluoride levels in certain areas. Risk assessments, including Hazard Quotient results showed that 71%, 61% 38%, and 34% of groundwater samples exceededthe permissible THI limit (THI > 1) for infants, children, teenagers, and adults, respectively. The study recommends implementing measures such as denitrification, defluorination, rainwater harvesting, and improved sanitation infrastructure to enhance the health conditions in the study region. Additionally, it suggests introducing educational programs in rural areas to create awarenessabout the health dangers due to consumptionof water with high fluoride levels.

Preliminary results on novel adjuvant combinations suggest enhanced immunogenicity of whole inactivated pandemic influenza vaccines

Due to the inherent risk of a further pandemic influenza outbreak, there is a need and growing interest in investigating combinations of prophylactic vaccines and novel adjuvants, particularly to achieve antigen dose sparing and improved immunogenicity. Influenza is a highly variable virus, where the specific vaccine target is constantly changing, representing a major challenge to influenza vaccine development. Currently, commercial inactivated influenza vaccines have a poor CD8+ T response, which impacts cross-reactivity and the duration of response. Adjuvanted influenza vaccines can increase immune responses, thereby achieving better protection and cross-reactivity to help contain the spread of the disease. An early exploration of a hybrid cholesterol-PLGA nanoparticle delivery system containing the saponin tomatine and a NOD2 (nucleotide-binding oligomerization domain 2) agonist called SG101 was conducted. This combination was preliminarily evaluated for its ability to induce cellular immunity when combined with whole inactivated virus (WIV) influenza vaccine. After the adjuvants were manufactured using a single emulsion process, two formulations with different drug loadings were selected and physico-chemically characterized, showing sizes between 224 ± 32 and 309 ± 45 nm and different morphologies. After ensuring the lack of in vitro toxicity and hemolytic activity, a pilot in vivo assay evaluated the hybrid nanoparticle formulation for its ability to induce humoral and cellular immunity when combined with whole inactivated virus (WIV) H5N1 influenza vaccine by intramuscular administration in mice. Hemagglutinin inhibition (HAI) titers for adjuvanted groups showed no significant difference compared to the group vaccinated with the antigen alone. It was similar for CD4+ and CD8+ T cell responses, although the high drug loading formulation induced higher titers of IFNγ-positive CD8+ T cells. These proof-of-concept results encourage further investigations to develop the hybrid formulation with increased or different loading ratios, to investigate manufacturing optimization, and to evaluate the role of the individual immunostimulatory compounds in immune responses.

High viral loads combined with inflammatory markers predict disease severity in hospitalized COVID-19 patients: Results from the NOR-Solidarity trial.

To investigate temporal changes in the association between SARS-CoV2 viral load (VL) and markers of inflammation during hospitalization, as well as the ability of these markers alone or in combination to predict severe outcomes. Serial oropharyngeal and blood samples were obtained from hospitalized COVID-19 patients (n=160). Levels of inflammatory markers and oropharyngeal VL were measured during hospitalization (admission, days 3-5, and days 7-10) and related to severe outcomes (respiratory failure/intensive care unit admission). Elevated admission levels of IL (interleukin)-6, IL-33, IL-8, monocyte chemoattractant protein-1 (MCP-1), interferon-γ-induced protein 10 (IP-10), IL-1β, and IL-1Ra were associated with severe outcomes during hospitalization. Although no inflammatory markers correlated with VL at baseline, there was a significant correlation between VL and levels of IP-10 and MCP-1 at days 3-5, accompanied by IL-8 and IL-6 at days 7-10. Finally, there was a seemingly additive effect of IP-10, MCP-1, and IL-6 in predicting severe outcomes when combined with high VL at baseline. An increasing number of inflammatory markers were associated with VL during the first 10 days of hospitalization, and several of these markers were associated with severe outcomes, in particular when combined with elevated VL. Future studies should assess the potential for combining antiviral and immunomodulatory treatment, preferably guided by viral and inflammatory biomarkers, for the selection of high-risk patients.

Analyzing Key Factors on Training Days within a Standard Microcycle for Young Sub-Elite Football Players: A Principal Component Approach

Utilizing techniques for reducing multivariate data is essential for comprehensively understanding the variations and relationships within both biomechanical and physiological datasets in the context of youth football training. Therefore, the objective of this study was to identify the primary factors influencing training sessions within a standard microcycle among young sub-elite football players. A total of 60 male Portuguese youth sub-elite footballers (15.19 ± 1.75 years) were continuous monitored across six weeks during the 2019–2020 in-season, comprising the training days from match day minus (MD-) 3, MD-2, and MD-1. The weekly training load was collected by an 18 Hz global positioning system (GPS), 1 Hz heart rate (HR) monitors, the perceived exertion (RPE) and the total quality recovery (TQR). A principal component approach (PCA) coupled with a Monte Carlo parallel analysis was applied to the training datasets. The training datasets were condensed into three to five principal components, explaining between 37.0% and 83.5% of the explained variance (proportion and cumulative) according to the training day (p < 0.001). Notably, the eigenvalue for this study ranged from 1.20% to 5.21% within the overall training data. The PCA analysis of the standard microcycle in youth sub-elite football identified that, across MD-3, MD-2, and MD-1, the first was dominated by the covered distances and sprinting variables, while the second component focused on HR measures and training impulse (TRIMP). For the weekly microcycle, the first component continued to emphasize distance and intensity variables, with the ACC and DEC being particularly influential, whereas the second and subsequent components included HR measures and perceived exertion. On the three training days analyzed, the first component primarily consisted of variables related to the distance covered, running speed, high metabolic load, sprinting, dynamic stress load, accelerations, and decelerations. The high intensity demands have a high relative weight throughout the standard microcycle, which means that the training load needs to be carefully monitored and managed.

Protozoan communities serve as a strong indicator of water quality in the Nile River

The relationship between the protozoan communities and environmental variables was studied in the Nile River to evaluate their potential as water quality indicators. Protozoans were sampled monthly at six sampling sites in the Nile's Damietta Branch across a spatial gradient of environmental conditions during a 1-year cycle (February 2016–January 2017). The Protozoa community was comprised of 54 species belonging to six main heterotrophic Protozoa phyla. The abundance (average, 1089 ± 576.18 individuals L−1) and biomass (average, 86.60 ± 106.13 μg L−1) were comparable between sites. Ciliates comprised the majority of protozoan species richness (30 species), abundance (79.72%), and biomass (82.90%). Cluster analysis resulted in the distribution of protozoan species into three groups, with the most dominant species being the omnivorous ciliate Paradileptus elephantinus. Aluminium, fluoride, and turbidity negatively affected abundance and biomass, while dissolved oxygen and potassium positively impacted biomass. Of the dominant species recorded over the study area, the amoebozoa Centropyxis aculeata was associated with runoff variables, while the bacterivorous ciliates Colpidium colpoda, Glaucoma scintillans, and Vorticella convallaria were related to the abundance of heterotrophic bacteria, phytoplankton biomass, and total organic carbon. Total dissolved salts, PO4, NH3, NO2, dissolved oxygen, and total organic carbon were the strongest causative factors for protozoa distribution. The α-Mesosaprobic environment at site VI confirmed a high load of agricultural runoffs compared to other sites. This study demonstrates that protozoans can be a potential bioindicator of water quality status in this subtropical freshwater river system.