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Understanding the colour preference in microgravity environments will enable better design of future spacecraft and extra-terrestrial environments. In this study, a space station's crew cabin was simulated and evaluated in 33 different colours by 55 participants using a standard body position change methodology in controlled conditions. Three body positions were tested, and included normal sitting position (SP), to reflect terrestrial conditions; −15° head-down (HD) bed rest, to simulate a microgravity state; and 9.6° head-up tilt (HU) bed rest, to simulate a lunar gravity state. VR devices were worn by participants to ensure an immersive environment in which to evaluate the different coloured environments across the three different body positions. The results show that in all colour environments, there was no significant difference in the colour preference between SP and HU, but there was a significant change in the colour preference in HD compared to SP and HU. In the three positions, the participants appeared to prefer lighter colours rather than darker ones, warmer colours in ST and HU, and cool colours in HD. In this short-term simulation study, no evidence of gender differences in colour preference by body position was found, but in each body position, men and women had different preference levels for basic hue and chroma brightness. • Colour preference during normal sitting, −15° head-down bed rest and 9.6° head-up tilt bed rest was assessed. • A significant change in colour preference during −15° head-down (HD) bed rest was found. • In the three positions, the participants appeared to prefer lighter colours rather than darker ones. • No gender differences in colour preference by body position were found in this short-term simulation study. [ABSTRACT FROM AUTHOR]

DOT1L mediates the methylation of histone H3 at lysine 79 and, in turn, the transcriptional activation or repression in a context-dependent manner, yet the regulatory mechanisms and functions of DOT1L/H3K79me remain to be fully explored. Following peptide affinity purification and proteomic analysis, we identified that DCAF1—a component of the E3 ligase complex involved in HIV regulation—is associated with H3K79me2 and DOT1L. Interestingly, blocking the expression or catalytic activity of DOT1L or repressing the expression of DCAF1 significantly enhances the tumor necrosis factor alpha (TNF-α)/nuclear factor κB (NF-κB)-induced reactivation of the latent HIV-1 genome. Mechanistically, upon TNF-α/NF-κB activation, DCAF1 is recruited to the HIV-1 long terminal repeat (LTR) by DOT1L and H3K79me2. Recruited DCAF1 subsequently induces the ubiquitination of NF-κB and restricts its accumulation at the HIV-1 LTR. Altogether, our findings reveal a feedback modulation of HIV reactivation by DOT1L-mediated histone modification regulation and highlight the potential of targeting the DOT1L/DCAF1 axis as a therapeutic strategy for HIV treatment. [Display omitted] • Peptide affinity purification identifies proteins recognizing methylated histone H3K79 • DCAF1 is associated with both H3K79me2 and DOT1L • DOT1L/H3K79me2 facilitates recruitment of DCAF1 to constrain HIV-1 reactivation • DCAF1 promotes ubiquitination of NF-κB and suppresses its level at HIV-1 LTR Liang et al. demonstrated that DOT1L/H3K79me2, in conjunction with DCAF1, establishes a negative feedback loop to restrict HIV-1 reactivation by inhibiting NF-κB binding at LTR. [ABSTRACT FROM AUTHOR]

This study investigated the effects of nine colour environments on visual tracking accuracy and visual strain during normal sitting (SP), −12° head-down bed (HD) and 9.6° head-up tilt bed (HU). In a standard posture change laboratory study, fifty-four participants performed visual tracking tasks in nine colour environments while in the three postures. Visual strain was measured by means of a questionnaire. The results showed that in all colour environments, the −12° head-down bed rest posture significantly affected visual tracking accuracy and visual strain. During the three postures, the participants' visual tracking accuracy in the cyan environment was significantly higher than that in other colour environments, and their visual strain was the lowest. Overall, the study adds to our understanding of how environmental and postural factors impact on visual tracking and visual strain. • The effects of nine colour environments on visual tracking and visual strain during normal sitting, −12° head-down bed rest and 9.6° head-up tilt bed rest were assessed. • The −12° head-down bed rest posture significantly affected visual tracking accuracy and visual strain. • In the three postures, visual tracking accuracy in the cyan environment was the best and visual strain was at the lowest level, while visual tracking accuracy was worst in the grey environment. In the red environment, visual strain increased significantly. [ABSTRACT FROM AUTHOR]

This study implemented a short-term virtual reality examination of the impacts of environmental colour and posture changes (to simulate microgravity and lunar gravity) on cognitive task performance and emotions. In a standard posture change laboratory study, sixty participants performed a simple cognitive task battery (finding A's test and number comparison test) and an emotional state questionnaire within nine different colour scenes while using three postures (normal sitting (SP), −12° head-down bed (HD) and 9.6° head-up tilt bed (HU)). The results showed that in all colour scenes, the HD posture significantly reduced the participants' task performance and level of positive emotions. There was also some variability in task performance and emotional reaction by scene colour. Overall, the study adds to our understanding of how environmental and postural factors impact on cognition and emotion. • Cognitive task performance and emotions were assessed while varying environmental colour and body posture (normal sitting, −12° head-down bed rest and 9.6° head-up tilt bed rest) within virtual reality. • The −12° head-down bed rest posture significantly reduced cognitive task performance and reported positive emotions. • Across postures, task performance in the cyan scene was the best and negative emotions were at the lowest level, while task performance in the grey scene was the worst. In the red scene, negative emotions increased significantly. • The effects of posture and colour did not interact for any of the outcome measures, posture had statistically equivalent impacts across the different colour scenes, and vice versa. [ABSTRACT FROM AUTHOR]

The adsorption mechanism of collectors on minerals is of fundamental importance in the research and development of flotation science and processing technology. To examine the effect of cationic dodecylamine hydrochloride (DDAH), anionic sodium oleate (NaOL) and mixed DDAH/NaOL surfactants with different molar ratios on the adsorption behavior on the muscovite (001) surface, the adsorption mechanism of DDAH, NaOL and their mixture on the muscovite (001) surface in neutral aqueous solution was investigated by molecular dynamics (MD) simulations. The results showed that the cationic DDAH molecules absorb on the muscovite (001) surface by electrostatic interactions and hydrogen bonding, whereas the anionic NaOL molecules cannot independently adsorb on the muscovite surface. Based on the analysis of the density distribution profile, radial distribution function (RDF) and interaction energy between surfactant molecules and muscovite surface, and the root mean square displacement (RMSD) of surfactants on water-muscovite interface, individual DDAH surfactant is a superior collector for the muscovite flotation. The molar ratio of DDAH/NaOL surfactants is found to be a key factor in the flotation response of muscovite. No significant adsorption of 1:2, 1:3 and 1:4 mixed DDAH/NaOL surfactants on the muscovite surface can be detected, while an effective adsorption was observed for the DDAH/NaOL mixture in molar ratios of 1:1, 2:1, 3:1 and 4:1. The cationic DDAH surfactant was determined to play a primary role in the adsorption of the mixed surfactants on the muscovite surface, while the anionic NaOL molecules co-adsorb with the DDAH molecules. The additional micro-flotation experiments under neutral aqueous conditions also showed that the flotation recovery of muscovite was the highest in the presence of DDAH surfactant, which was consistent with the findings derived from MD simulations. [Display omitted] • The adsorption mechanism of DDAH/NaOL on muscovite surface in neutral aqueous solution was investigated by MD simulations. • In all systems, the DDAH alone (D30) showed the best adsorption performance of muscovite under neutral aqueous conditions. • The mixed DDAH/NaOL surfactant in molar ratio of 1:1 has the best flotation performance of muscovite than other molar ratios. • The micro-flotation experiments results under neutral aqueous conditions were consistent with the MD simulations. [ABSTRACT FROM AUTHOR]

Abstract: A series of bending tests of thin-walled concrete-filled steel tubes (CFST) were presented in this study. A total of 4 specimens were tested, two square specimens and two rectangular specimens, with width to wall thickness ratio ranging from 50 to 100. The load–displacement curves, failure mode and ultimate capacity of test specimens were obtained. An analytical model was developed for the thin-walled CFSTs subjected to bending. Material properties of confined concrete, corner strength enhancement of cold-formed steel sections, residual stresses and plate local buckling were considered in the developed model. The proposed model was able to predict the behavior and strengths of test specimens with reasonable accuracy. In addition, the suitability of current AISC standard, Eurocode 4 and Han''s model for thin-walled CFSTs subjected to bending was also evaluated. [Copyright &y& Elsevier]

This paper aims to explore colour schemes to reduce stress response in the hygiene area of a space station. We conducted a two-stage exploratory Delphi-study with 30 international experts. It was found that the overall environment, stool-urine collection device, garbage collection interface and negative pressure package interface of the hygiene area most affected astronauts' experience. Remarkably, experts have highest visual requirements for the cleanliness of the overall environment and for stool and urine collection devices in the hygiene area. These tend to have low saturation and low blackness colours, while the garbage collection interface and negative pressure package interface have conspicuity and discernibility visual requirements. It was found that experts tend to choose high saturation and high brightness colours. • 30 international experts assessed the colour scheme to reduce the stress response in the hygiene area of a space station. • Low-saturation and low-blackness colours need to be applied to the overall environment, Stool and urine collection device. • The garbage collection and negative pressure packaging interface need to adopt high saturation and high brightness colours. [ABSTRACT FROM AUTHOR]

[Display omitted] Natural small molecules derived from plants have fascinated scientists for centuries due to their practical applications in various fields, especially in nanomedicine. Some of the natural molecules were found to show intrinsic optical features such as fluorescence emission and photosensitization, which could be beneficial to provide spatial temporal information and help tracking the drugs in biological systems. Much efforts have been devoted to the investigation of optical properties and practical applications of natural molecules. In this review, optical properties of natural small molecules and their applications in fluorescence imaging, and theranostics will be summarized. First, we will introduce natural small molecules with different fluorescence emission, ranging from blue to near infrared emission. Second, imaging applications in biological samples will be covered. Third, we will discuss the applications of theranostic nanomedicines or drug delivering systems containing fluorescent natural molecules acting as imaging agents or photosensitizers. Finally, future perspectives in this field will be discussed. [ABSTRACT FROM AUTHOR]

This paper aims to explore colour schemes to reduce stress response in the hygiene area of a space station. We conducted a two-stage exploratory Delphi-study with 30 international experts. It was found that the overall environment, stool-urine collection device, garbage collection interface and negative pressure package interface of the hygiene area most affected astronauts' experience. Remarkably, experts have highest visual requirements for the cleanliness of the overall environment and for stool and urine collection devices in the hygiene area. These tend to have low saturation and low blackness colours, while the garbage collection interface and negative pressure package interface have conspicuity and discernibility visual requirements. It was found that experts tend to choose high saturation and high brightness colours. [ABSTRACT FROM AUTHOR]

Objective Hydrogen sulfide has been recognized as an important neuroprotective agent in the nervous system. The present study aimed to study the effect and the underlying mechanisms of hydrogen sulfide on spinal cord ischemia-reperfusion injury (SCII). Methods The gene mRNA and protein expression were examined by RT-PCR and western blot, respectively. Spinal cord infarct zone was analyzed by Triphenyltetrazolium chloride staining. Cell apoptosis was detected by MTT assay. The relationship between miR-30c and CasC7 was analyzed by RNA immunoprecipitation (RIP) and RNA pull-down. Results We observed that SCII rat model have a bigger spinal cord infarct zone than the control rat, but NaSH preprocessing could reduce spinal cord infarct zone in SCII rat. OGD/R induced cell apoptosis, and NaSH preprocessing reduced the OGD/R-induced SH5Y-SY cells apoptosis. CasC7 was decreased in SCII rat and OGD/R-induced SH5Y-SY cells, while miR-30c expression was increased. NaSH preprocessing upregulated CasC7 and downregulated miR-30c in OGD/R-induced SH5Y-SY cells. In OGD/R induced SH5Y-SY cells with NaSH preprocessing, knockdown of CasC7 could upregulate miR-30c expression, promote cell apoptosis and downregulate miR-30c’s target gene expression. The RIP and RNA pull-down demonstrated that CasC7 functioned as a miR-30c decoy, and miR-30c inhibitor could reverse the effect of si-CasC7. Moreover, intrathecal injection of si-CasC7 upregulated miR-30c expression and increased spinal cord infarct zone in SCII rat with NaSH preprocessing. Conclusion Hydrogen sulfide protects spinal cord by upregulating CasC7 expression in SCII rat model. [ABSTRACT FROM AUTHOR]

The ripening characteristics after capping of honey are favourable for improving its quality. However, research on the variation and formation of aroma characteristics of honey in this process is lacking. Therefore, the present study was carried out with different stages of Rhus chinensis honeys (RCHs) after capping and identified 192 volatiles with varying levels of concentration. "Fruity" was the main aroma characteristic of RCHs at different stages after capping, mainly contributed by (E)- β -damascenone. Methyl salicylate might be a potential indicator for differentiating RCHs at different stages after capping. The metabolic pathway analyses revealed that the aroma compounds in RCHs undergo transformation at different stages after capping, which subsequently affects its aroma characteristics formation. This work is the first to study the dynamic changes in honey aroma characteristics after capping from multiple perspectives, and the results are of great significance for understanding the aroma characteristics after capping and quality control of honey. • "Fruity" aroma is the main aroma characteristic of RCHs, mainly contributed by (E)- β -damascenone. • A significant correlation (P <0.05) was found between acids and "fruity" and "herbaceous" aromas. • Methyl salicylate might be a potential marker for differentiating RCHs at different stages after capping. • Mutual transformation of aroma compounds might affect RCHs aroma characteristics. [ABSTRACT FROM AUTHOR]

Honey is a precious natural product with high nutritional and medicinal values, which both depend on its botanical origin. However, honey is susceptible to adulteration and false labeling claims of plant origin, its botanical origin certification has become a global challenge due to the complex nature of honey and the various types of adulteration. Therefore, it is crucial to establish accurate, rapid, and comprehensive methods for identifying the botanical origin of honey to ensure its quality. Foodomics, one of the most rapidly developing technologies in recent years, is a powerful tool for determining food components and nutrients at the molecular level. It is increasingly used in honey authentication due to its advantages, such as high throughput and wide applicability. This review provides an overview of the research progress made in authenticating the botanical origin of honey using omics techniques over the past decade (2013–2023). This paper describes the differences in the chemical composition and sensory characteristics of honey from different plant varieties. It is found that metabolomics has been widely used in honey plant origin identification studies, and current studies mainly apply various advanced instruments combined with different chemometrics to discover unique markers or establish classification models. It is strongly recommended to apply multiple omics analysis techniques jointly to increase the compound coverage, to explore the metabolic pathways and changes of metabolites from plants to honey, and then to its maturity throughout the process, to provide comprehensive information for future omics studies. [Display omitted] • The effects of plant sources on the sensory characteristics and chemical composition of honey are reviewed. • Omics technologies can comprehensively identify markers that reflect the plant source of honey. • Omics technologies can be combined with different chemometrics to achieve more accurate and efficient identification. • Metabolomics, proteomics and genomics approaches in honey plant source authentication are discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • The variation of volatile compounds during the ripening stages of DDHs was first studied. • The "fruity" aroma was the dominant aroma characteristic of DDHs and became richer with the increasing maturity. • The enantiomeric content and distribution of linalool oxide A enantiomers may be a potential indicator to identify the maturity of DDHs; • Only the enantiomer R -linalool (OAVs: 5.56–6.14) was found to be an important contributor to the aroma profiles of DDHs at different stages of maturity. Dendropanax dentiger honey (DDH) is a specialty herbal honey from China. Previous research on DDH has mostly focused on its composition and potential chemical markers, no studies have been conducted on the changes in aroma characteristics and chiral odorants during its maturation. Therefore, the present study aims to address the missing parts. The proportions and total concentrations of 185 volatile compounds identified in different classes varied with DDHs ripening. Fourteen common odor-active compounds were identified by odor activity values (OAVs) and GC-olfactometry (GC-O) analysis. The aroma profiles of DDHs were observed to vary at different ripening stages, although the dominant aroma characteristic was "fruity" aroma, which became more pronounced with increasing maturity. The enantiomeric contents and distributions of 7 volatile enantiomers were related to specific physicochemical indicators and the maturity of DDHs, among which the enantiomers of linalool oxide A may be a potential indicator to identify its maturity. Furthermore, precise quantification and OAVs calculation showed that the enantiomer (2 S , 5 S)-linalool oxide A presented the highest concentration (8.83–27.39 ng/mL) and only the enantiomer R -linalool (OAVs: 5.56–6.14) was an important contributor to the aroma profiles of DDHs at different stages of maturity. These results provided a new research idea for quality control and identification of DDHs at different maturity stages. [ABSTRACT FROM AUTHOR]

Livestock grazing can alter biodiversity and ecosystem functions. However, how long-term and continuous grazing intensity affect belowground biodiversity remains unclear, especially for soil microbial diversity. Here, through a well-controlled 5-year field experiment in a Tibetan alpine meadow, the responses of soil bacterial and fungal communities to yak grazing intensity were examined. Our results showed that grazing intensity significantly changed soil bacterial and fungal community compositions, rather than microbial α-diversity. The co-occurrence network analysis indicated that both soil bacterial and fungal network complexity gradually decreased with increasing grazing intensities. Meanwhile, soil C/N ratio, soil moisture, dissolved organic nitrogen (DON), NH 4 +-N, and aboveground biomass (AGB) were related to soil bacterial community, and AGB, NO 3 --N, NH 4 +-N, and DON and were associated with soil fungal community. Taken together, our manipulative experiment provides empirical evidence that grazing intensity-induced alterations of aboveground vegetation and nitrogen availability primarily trigger the shift of soil microbial community and structure. These results can support grassland management and ecological restoration in alpine ecosystems. • Yak grazing alters soil microbial community compositions, rather than α-diversity. • Microbial network complexity decreases with increasing yak grazing intensities. • Plant biomass and nitrogen availability jointly affect soil microbial community. [ABSTRACT FROM AUTHOR]

2-Methylfuran (MF), an environmental-friendly biofuel, has drawn extensive attention from fuel researchers. In this study, the particulate matter (PM) and unregulated emissions of diesel engine were investigated. All experiments were performed in a direct injection compression ignition (DICI) engine fueled with diesel–MF blends (10%, 20% and 30% mass fractions of MF were blended with diesel). The test conditions were a constant speed of 1800 rpm and load from 0.13 to 1.13 MPa brake mean effective pressure (BMEP). Among the tested fuels, the emissions of 1,3-butadiene, benzene and acetaldehyde are all decreased with the increase of engine load except benzene of M30 at 1.13 load. In addition, the diesel–MF blends promote acetaldehyde emissions, but reduce benzene and 1,3-butadiene emissions. At the engine load of 0.38 MPa BMEP, with the increase of MF fraction in blends, more particle numbers for both nucleation mode and accumulation mode are yielded than pure diesel. At 0.88 and 1.13 MPa BMEP, with the increment of MF ratio in blend fuels, the particle numbers rise at small diameter of particle (Dp) (5–10 nm) compared to pure diesel, but decline at large diameter of particle (Dp) (10–250 nm). The increment of MF blending ratio increases the particulate number concentration. Moreover, with the rise of MF mass fraction in the mixtures, the particulate mass concentration decreases gradually at above 0.63 MPa BMEP. However, particulate mass concentration of M30 is the highest at lower loads. [ABSTRACT FROM AUTHOR]

Currently, worldwide interest has been triggered in the potential of 2,5-dimethylfuran (DMF) due to the discovery of improved production methods. However, the combustion and emission properties of DMF have been rarely characterized. Here we studied how the fuel properties and loads affected the combustion and emission of diesel–DMF blends or pure diesel in a four-cylinder direct-injection compression-ignition (DICI) engine. The experimental conditions were load from 0.13 to 1.13 MPa brake mean effective pressure (BMEP) and constant speed at 1800 rpm. We find at 0.38 MPa BMEP, the maximum heat release rate (HRR) rises and the peak cylinder pressure decreases both significantly with the increase of DMF mass fraction in the blends. However, at 0.63 MPa BMEP, the peak cylinder pressure and HRR both increased with the rise of DMF mass fraction. For each tested fuel, the emissions of 1,3-butadiene, benzene and acetaldehyde all declined with the increment of load. In addition, the DMF and diesel blending increased the acetaldehyde emission and reduced the benzene and 1,3-butadiene emissions. The nucleation mode greatly dominated the particle size distribution within the entire load range. The DMF and diesel blending tended to reduce particulate mass concentration and number concentration under most operating conditions. At 1.13 MPa BMEP, however, the DMF and diesel blending tended to increase particulate number concentration. [ABSTRACT FROM AUTHOR]