A comparative study on contamination profiles of liquid crystal monomers (LCMs) between outdoor and indoor dusts, and the assessment of health risk of human exposure.

Liquid crystal monomers (LCMs) are ubiquitous in various environmental samples, which has led to increasing concerns regarding their potential health risks to humans and wildlife. However, the comparison of the contamination patterns of LCMs between indoor and outdoor environments has rarely been studied. In this study, 35 LCMs were investigated in n = 55 dust samples collected from indoor (n = 20) and outdoor (n = 35) spaces in Yulin, Northwest China. The LCMs were widely detected in indoor and outdoor dusts; the total concentrations of LCMs ranged from 48.6 to 396 ng/g (median: 153 ng/g), and from not detectable to 388 ng/g (median: 56.4 ng/g) in indoor and outdoor dusts, respectively. The concentration levels of ΣLCMs in indoor dusts were significantly higher than those in outdoor dusts (p < 0.05). For each microenvironment, the ranking order of LCM concentrations was dormitory (mean: 202 ng/g) > teaching building (182 ng/g) > campus road (150 ng/g) > urban road (107 ng/g) > laboratory building (91.0 ng/g) > pedestrian street (20.1 ng/g). The mean estimated daily intake values of Σ35LCMs for adults were 2.48 × 10-2 and 1.37 × 10-3 ng/g BW/day in indoor and outdoor dusts, respectively. The hazard quotients of individual LCMs and hazard indices of all analytes were considerably less than one, indicating little health risk for humans via dust ingestion.

Neural predictors of fear depend on the situation.

The extent to which neural representations of fear experience depend on or generalize across the situational context has remained unclear. We systematically manipulated variation within and across three distinct fear-evocative situations including fear of heights, spiders, and social threats. Participants (n=21, 10 females and 11 males) viewed ∼20 second clips depicting spiders, heights, or social encounters, and rated fear after each video. Searchlight multivoxel pattern analysis (MVPA) was used to identify whether and which brain regions carry information that predicts fear experience, and the degree to which the fear-predictive neural codes in these areas depend upon or generalize across the situations. The overwhelming majority of brain regions carrying information about fear did so in a situation dependent manner. These findings suggest that local neural representations of fear experience are unlikely to involve a singular pattern, but rather a collection of multiple heterogeneous brain states.Significance Statement Much of the debate on the nature of emotion concerns the uniformity or heterogeneity of representation for particular emotion categories. Here we provide evidence that widely distributed activation patterns characteristic of recent neural signatures of fear reflect an amalgam of functionally heterogeneous brain states. Participants completed a novel fMRI task that parametrically examined subjective fear within and across three content-rich and naturalistic situations: fear of heights, spiders, and social threats. Using searchlight analysis and machine learning methods, we show that the overwhelming majority of brain regions that predict fear only do so for certain situations. These findings carry implications for the generalization of findings on fear across species, translational models of fear and anxiety, and developing neural signatures of fear.

Alterations of the microbiome across body sites in systemic lupus erythematosus: A systematic review and meta-analysis.

BACKGROUND: Systemic lupus erythematosus (SLE) is a complex autoimmune disease with unclear etiology. Growing evidence suggests the microbiome plays a role in SLE pathogenesis. However, findings are inconsistent across studies due to factors like small sample sizes and geographical variations. A comprehensive meta-analysis is needed to elucidate microbiome alterations in SLE. OBJECTIVE: This study aimed to provide a systematic overview of microbiota dysbiosis across body sites in SLE through a meta-analysis of alpha diversity indices, beta diversity indices, and abundance taxa of microbiome. METHODS: A literature search was conducted across four databases to identify relevant studies comparing SLE patients and healthy controls. Extracted data encompassed alpha and beta diversity metrics, as well as bacterial, fungal, and viral abundance across gut, oral, skin, and other microbiota. Study quality was assessed using the Newcastle-Ottawa Scale. Standardized mean differences and pooled effect sizes were calculated through meta-analytical methods. RESULTS: The analysis showed reduced alpha diversity and distinct beta diversity in SLE, particularly in the gut microbiota. Taxonomic analysis revealed compositional variations in bacteria from the gut and oral cavity. However, results for fungi, viruses, and bacteria from other sites were inconsistent due to limited studies. CONCLUSIONS: This meta-analysis offers a comprehensive perspective on microbiome dysbiosis in SLE patients across diverse body sites and taxa. The observed variations underscore the microbiome's potential role in SLE pathogenesis. Future research should address geographical variations, employ longitudinal designs, and integrate multi-omics approaches.

The correlation between single and mixed trace elements exposure in systemic lupus erythematosus: A case-control study.

BACKGROUND: Recent studies have shown an association between trace elements and systemic lupus erythematosus (SLE), but the relationship between trace elements and SLE is still unclear. This study aims to determine the distribution of plasma trace elements in newly diagnosed SLE patients and the association between these essential and toxic element mixtures and SLE. METHODS: In total, 110 SLE patients and 110 healthy controls were included. Blood samples were collected. 15 plasma trace elements were quantified using an inductively coupled plasma mass spectrometer (ICP-MS). Multivariate logistic regression, restricted cubic spline (RCS), weighted quantile sum (WQS) regression, quantile g-computation (qgcomp), and Bayesian kernel machine regression (BKMR) are used to analyze the association between single and mixed exposure of elements and SLE. RESULTS: The logistic regression model shows that, plasma lithium (Li) [OR (95 % CI): 1.963 (1.49-2.586)], vanadium (V) [OR (95 % CI): 2.617(1.645-4.166)] and lead (Pb) [OR (95 % CI): 1.603(1.197-2.145)] were positively correlated with SLE, while selenium (Se) [OR (95 % CI): 0.055(0.019-0.157)] and barium (Ba) [OR (95 % CI): 0.792(0.656-0.957)] had been identified as protective factors for SLE. RCS results showed a non-linear correlation between the elements Li, V, Ni, copper, Se, rubidium and SLE. In addition, WQS regression, qgcomp, and BKMR models consistently revealed significant positive effects of plasma Li and Pb on SLE, as well as significant negative effects of plasma Se. CONCLUSIONS: Exposure to heavy metals such as Li and Pb is significantly positively correlated with SLE, but Se may be protective factors for SLE. In addition, there is a nonlinear correlation between the elements Li and Se and SLE, and there are complex interactions between the elements. In the future, larger populations and prospective studies are needed to confirm these associations.

Synergism of salvianolic acid B and ginsenoside Rg1 magnifies the therapeutic potency against ischemic stroke.

Even though considerable progress has been made to reduce insult, ischemic stroke is still a significant cause of mortality and morbidity in the world, and new therapeutic strategies are urgently needed. In the present study, the magnesium salt of salvianolic acid B (SalB) and ginsenoside Rg1 (Rg1) combination as a multicomponent strategy against stroke was evaluated. The synergistic effect of Sa1B and Rg1 was evaluated by Bliss independence analysis on the middle cerebral artery occlusion model. The infarct volume, neuroethology, cerebral structure, and neurocyte number were evaluated by 3,5-triphenyltetrazolium chloride staining, Longa score, Garcia score, hematoxylin-eosin staining, and Nissl staining, respectively. Metabolomics was used to search for potential biomarkers and explore the mechanism of Sa1B/Rg1. First, the superior effects of SalB/Rg1 than SalB or Rg1 at the same dose were evaluated. Compared with SalB ( P  < 0.001) or Rg1 ( P  < 0.01), SalB/Rg1 significantly decreased infarct volume through 3,5-triphenyltetrazolium chloride staining and protected the structural integrity of cortex and striatum. The superior effect of SalB/Rg1 on neurological behavior was also detected compared with SalB or Rg1 significantly. Accompanying behavioral improvement, a considerable increase of SalB/Rg1 on neurons detected by Nissl staining was found on the cortex compared with SalB ( P  < 0.05) or Rg1 ( P  < 0.01). Second, the synergistic effect between SalB and Rg1 was strictly verified by Bliss independence analysis ( P  < 0.01) based on infarct volume. Finally, alleviation of cerebral metabolic disorders may be the possible mechanism of SalB/Rg1. Our study provided a multicomponent strategy against ischemic stroke, with not only dose reduction but also improved efficacy relative to single agents.

Enhancement of zein-based films for mango preservation using high-intensity ultrasound and castor oil plasticization.

Zein-based films exhibit high efficiency in ethylene adsorption. However, its brittleness limits the practical applications. To address this issue, this study synergizes the plasticizing effects of high-intensity ultrasound (HIU) and castor oil (CO) to reduce the brittleness of zein-based films. The plasticizing mechanism was demonstrated through the formation of new intermolecular hydrogen bonds and electrostatic interactions, as evidenced by fourier transform infrared spectroscopy (FTIR) and zeta potential measurements. The tensile strength of 6 % CO-zein film increased eightfold. Additionally, the freshness of mangoes stored with 6 % CO-zein film significantly improved, extending their shelf life from 5 days to 15 days. Therefore, this study investigated the synergistic plasticization of zein-based films through the addition of CO, based on HIU. It also provides a theoretical basis for fruit packaging.

Citrus polymethoxyflavones degrade estrogen receptor-alpha (ERα) and combine with tamoxifen for the treatment of estrogen receptor-positive breast cancer.

Estrogen receptor-positive (ER+) breast cancer seriously endangers the women's physical and mental health worldwide and ER targeting therapy is vital. Here, we found that a citrus polymethoxyflavones (PMFs)-rich hydrolysate (C-H) and its major components (nobiletin and 3-methoxynobiletin) potently degrade ERα protein via the ubiquitin-proteasome pathway, thereby impairing the proliferation of ER+ breast cancer cells. Moreover, our study exhibited that C-H combined with tamoxifen (TAM) inhibited the cell proliferation of ER+ breast cancer in vitro. It was further confirmed that C-H decreased tumor growth of ER+ breast cancer in tumor-bearing 129 mice in vivo and improved the efficacy of tamoxifen. Our study revealed that the citrus PMFs have potential applications as pharmaceutical and healthcare products in breast cancer treatment by targeting ERα protein degradation.

Carbon emission assessment of lithium iron phosphate batteries throughout lifecycle under communication base station in China.

The demand for lithium-ion batteries has been rapidly increasing with the development of new energy vehicles. The cascaded utilization of lithium iron phosphate (LFP) batteries in communication base stations can help avoid the severe safety and environmental risks associated with battery retirement. This study conducts a comparative assessment of the environmental impact of new and cascaded LFP batteries applied in communication base stations using a life cycle assessment method. It analyzes the influence of battery costs and power structure on carbon emissions reduction. Results indicate: When consuming the same amount of electricity in a cascaded battery system (CBS), LFP batteries with a retirement state of health (SOH) range between 76.5 % and 90.0 % can reduce 30.3 % of the global warming potential (GWP) compared to new batteries. From the perspective of battery costs, when the price ratio of new to old batteries is greater than 31.0 %, the GWP of batteries retired at 70.0 % SOH is higher than that of new batteries. As the proportion of renewable energy sources in the power structure increases, the GWP of new batteries in 2035 is 15.0 % lower than in 2020. For batteries retired at 80.0 % SOH, their GWP decreases by 12.3 % compared to 2020. This study offers a new approach to determining the retirement point for LFP batteries from an environmental perspective, promoting carbon emission reduction throughout the entire battery life cycle and the sustainable development of the transportation sector.

Comprehensive evaluation of the efficacy and safety of a new multi-component anti-aging topical eye cream.

BACKGROUND: The delicate periorbital region is susceptible to skin dehydration, wrinkles, and loss of elasticity. Thus, targeted and effective anti-aging interventions are necessary for the periorbital area. AIM: To evaluate the efficacy and safety of a new anti-aging eye cream formulated with the active complex (Yeast/rice fermentation filtrate, N-acetylneuraminic acid, palmityl tripeptide-1, and palmitoyl tetrapeptide-7). METHODS: The cell viability and expressions of key extracellular matrix (ECM) components of the active complex were evaluated using a human skin fibroblast model. In the 12-week clinical trial, skin hydration, elasticity, facial photographs, and collagen density following eye cream application were assessed using Corneometer, Cutometer, VISIA, and ultrasound device, respectively. Dermatologists and participants evaluated clinical efficacy and safety at baseline, and after 4, 8, and 12 weeks. RESULTS: PCR and immunofluorescent analyses revealed that the active complex significantly stimulated fibroblast proliferation (p < 0.05) and markedly promote the synthesis of collagen and elastin. Clinical findings exhibited a substantial enhancement in skin hydration (28.12%), elasticity (18.81%), and collagen production (54.99%) following 12 weeks of eye cream application. Dermatological evaluations and participants' assessments reported a significant improvement in skin moisture, roughness, elasticity, as well as fine lines and wrinkles by week 8. CONCLUSION: The new anti-aging eye cream, enriched with the active complex, demonstrates comprehensive rejuvenating effects, effectively addressing aging concerns in the periorbital area, coupled with a high safety profile.

Dark triad and knowledge hiding in firms: Mediating role of perceived organizational politics.

Negative behaviors at the workplace always disturb the management of the firms. This research investigates the link between the dark triad and various types of Knowledge hiding (Evasive hiding, Playing dumb, and Rationalized hiding) in firms. In addition, this study explores perceived organizational politics as a mediator. The design of this study is quantitative and positivist. The data were collected in three waves (45 days gap) with a random sampling approach from 383 personnel/staff working in Chinese commercial banking firms. The data were analyzed using the partial least squares structural equation modeling (PLS-SEM) technique and Smartpls-4 software. This study confirms that dark-triad has a positive relation with knowledge hiding, except psychopathy and Machiavellianism, which have no significant correlation with playing dumb and evasive hiding, respectively. Perceived organizational politics significantly mediate the association between dark triad personality traits and the types of knowledge hiding. Employees with political skills and a trust-based culture can counter the dark-triad personalities and discourage the knowledge-hiding culture. For effective management of knowledge-hiding issues in firms, codifying implicit and explicit Knowledge and developing knowledge repositories can discourage a knowledge-hiding culture.

A combination technique of strip free gingival grafts and xenogeneic collagen matrix in augmenting keratinized mucosa around dental implants: a single-arm clinical trial.

BACKGROUND: The aim of this study was to assess the outcomes of the combination technique of strip free gingival grafts (SFGG) and xenogeneic collagen matrix (XCM) in augmenting the width of keratinized mucosa (KMW) around dental implants, and compare its efficacy with the historical control group (FGG). METHODS: Thirteen patients with at least one site with KMW ≤ 2 mm after implant surgery were included and received SFGG in combination with XCM. Another thirteen patients with the same inclusion and exclusion criteria from the previous trial received FGG alone. The same outcomes as the previous trial were evaluated. KMW, thickness of keratinized mucosa (KMT), gingival index (GI) and probing depth (PD) were measured at baseline, 2 and 6 months. Postoperative pain, patient satisfaction and aesthetic outcomes were also assessed. RESULTS: At 6 months after surgery, the combination technique could attain 3.3 ± 1.6 mm of KMW. No significant change could be detected in GI or PD at 6 months compared to those at 2 months (p > 0.05). The postoperative pain and patient satisfaction in VAS were 2.6 ± 1.2 and 9.5 ± 1.2. The total score of aesthetic outcomes was 3.8 ± 1.2. In the historical FGG group, 4.6 ± 1.6 mm of KMW was reported at 6 months, and the total score of aesthetic outcomes was higher than the combination technique (4.8 ± 0.7 vs. 3.8 ± 1.2, p < 0.05). CONCLUSIONS: The combination technique of SFGG and XCM could increase KMW and maintain peri-implant health. However, this combination technique was associated with inferior augmentation and aesthetic outcomes compared with FGG alone. TRIAL REGISTRATION: This clinical trial was registered in the Chinese Clinical Trial Registry with registration number ChiCTR2200057670 on 15/03/2022.

Advances in Mechanism of HIV-1 Immune Reconstitution Failure: Understanding Lymphocyte Subpopulations and Interventions for Immunological Nonresponders.

In individuals diagnosed with AIDS, the primary method of sustained suppression of HIV-1 replication is antiretroviral therapy, which systematically increases CD4+ T cell levels and restores immune function. However, there is still a subset of 10-40% of people living with HIV who not only fail to reach normal CD4+ T cell counts but also experience severe immune dysfunction. These individuals are referred to as immunological nonresponders (INRs). INRs have a higher susceptibility to opportunistic infections and non-AIDS-related illnesses, resulting in increased morbidity and mortality rates. Therefore, it is crucial to gain new insights into the primary mechanisms of immune reconstitution failure to enable early and effective treatment for individuals at risk. This review provides an overview of the dynamics of key lymphocyte subpopulations, the main molecular mechanisms of INRs, clinical diagnosis, and intervention strategies during immune reconstitution failure, primarily from a multiomics perspective.

Environmental triggers of autoimmunity: The association between bisphenol analogues and systemic lupus erythematosus.

The aim of this research was to examine the correlation between the exposure to bisphenol analogues (BPs), such as bisphenol A (BPA), bisphenol F (BPF), and bisphenol S (BPS), and the risk of developing systemic lupus erythematosus (SLE). Ultra performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) was utilized to measure the levels of BPA, BPF, and BPS in the urine of 168 female participants diagnosed with SLE and 175 female participants who were deemed healthy controls. Logistic regression models were utilized to assess the connections between levels of bisphenol and the risk of SLE. The findings indicated that levels of BPA and BPF in the urine of individuals with SLE were markedly elevated compared to those in the control group. Higher exposure to BPA and BPF exhibited positive dose-response relationships with increased SLE risk. No significant associations were identified between BPS and the risk of SLE. These findings suggest exposure to BPA and BPF may be implicated as novel environmental triggers in the development of autoimmunity such as SLE. The significantly increased levels of these bisphenol analogues detected in SLE patients versus healthy controls, along with the associations between higher exposures and elevated SLE risk, which offers crucial hints for comprehending how endocrine-disrupting substances contribute to the genesis of autoimmune illnesses. Further research using robust longitudinal assessments of bisphenol analogue exposures is warranted to corroborate these epidemiological findings. Overall, this study highlights potential environmental risk factors for SLE while calling for additional investigation into the impact of bisphenol exposures on autoimmunity development.

No causal association between pneumoconiosis and three inflammatory immune diseases: a Mendelian randomization study.

Objectives: To investigate the causal relationships between pneumoconiosis and rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and gout. Methods: The random-effects inverse variance weighted (IVW) approach was utilized to explore the causal effects of the instrumental variables (IVs). Sensitivity analyses using the MR-Egger and weighted median (WM) methods were did to investigate horizontal pleiotropy. A leave-one-out analysis was used to avoid the bias resulting from single-nucleotide polymorphisms (SNPs). Results: There was no causal association between pneumoconiosis and SLE, RA or gout in the European population [OR = 1.01, 95% CI: 0.94-1.10, p = 0.74; OR = 1.00, 95% CI: 0.999-1.000, p = 0.50; OR = 1.00, 95% CI: 1.000-1.001, p = 0.55]. Causal relationships were also not found in pneumoconiosis due to asbestos and other mineral fibers and SLE, RA and gout [OR = 1.01, 95% CI: 0.96-1.07, p = 0.66; OR = 1.00, 95% CI: 1.00-1.00, p = 0.68; OR = 1.00, 95% CI: 1.00-1.00, p = 0.20]. Conclusion: Our study suggests that pneumoconiosis may have no causal relationship with the three inflammatory immune diseases.

The effect of inherent and incidental constraints on bimanual force control in simulated Martian gravity.

The ability to coordinate actions between the limbs is important for many operationally relevant tasks associated with space exploration. A future milestone in space exploration is sending humans to Mars. Therefore, an experiment was designed to examine the influence of inherent and incidental constraints on the stability characteristics associated with the bimanual control of force in simulated Martian gravity. A head-up tilt (HUT)/head-down tilt (HDT) paradigm was used to simulate gravity on Mars (22.3° HUT). Right limb dominant participants (N = 11) were required to rhythmically coordinate patterns of isometric forces in 1:1 in-phase and 1:2 multifrequency patterns by exerting force with their right and left limbs. Lissajous displays were provided to guide task performance. Participants performed 14 twenty-second practice trials at 90° HUT (Earth). Following a 30-min rest period, participants performed 2 test trials for each coordination pattern in both Earth and Mars conditions. Performance during the test trials were compared. Results indicated very effective temporal performance of the goal coordination tasks in both gravity conditions. However, results indicated differences associated with the production of force between Earth and Mars. In general, participants produced less force in simulated Martian gravity than in the Earth condition. In addition, force production was more harmonic in Martian gravity than Earth gravity for both limbs, indicating that less force distortions (adjustments, hesitations, and/or perturbations) occurred in the Mars condition than in the Earth condition. The force coherence analysis indicated significantly higher coherence in the 1:1 task than in the 1:2 task for all force frequency bands, with the highest level of coherence in the 1-4 Hz frequency band for both gravity conditions. High coherence in the 1-4 Hz frequency band is associated with a common neural drive that activates the two arms simultaneously and is consistent with the requirements of the two tasks. The results also support the notion that neural crosstalk stabilizes the performance of the 1:1 in-phase task. In addition, significantly higher coherence in the 8-12 Hz frequency bands were observed for the Earth condition than the Mars condition. Force coherence in the 8-12 Hz bands is associated with the processing of sensorimotor information, suggesting that participants were better at integrating visual, proprioceptive, and/or tactile feedback in Earth than for the Mars condition. Overall, the results indicate less neural interference in Martian gravity; however, participants appear to be more effective at using the Lissajous displays to guide performance under Earth's gravity.

Modulation of Motor Cortical Inhibition and Facilitation by Touch Sensation from the Glabrous Skin of the Human Hand.

Touch sensation from the glabrous skin of the hand is essential for precisely controlling dexterous movements, yet the neural mechanisms by which tactile inputs influence motor circuits remain largely unexplored. By pairing air-puff tactile stimulation on the hand's glabrous skin with transcranial magnetic stimulation (TMS) over the primary motor cortex (M1), we examined the effects of tactile stimuli from single or multiple fingers on corticospinal excitability and M1's intracortical circuits. Our results showed that when we targeted the hand's first dorsal interosseous (FDI) muscle with TMS, homotopic (index finger) tactile stimulation, regardless of its point (fingertip or base), reduced corticospinal excitability. Conversely, heterotopic (ring finger) tactile stimulation had no such effect. Notably, stimulating all five fingers simultaneously led to a more pronounced decrease in corticospinal excitability than stimulating individual fingers. Furthermore, tactile stimulation significantly increased intracortical facilitation (ICF) and decreased long-interval intracortical inhibition (LICI) but did not affect short-interval intracortical inhibition (SICI). Considering the significant role of the primary somatosensory cortex (S1) in tactile processing, we also examined the effects of downregulating S1 excitability via continuous theta burst stimulation (cTBS) on tactile-motor interactions. Following cTBS, the inhibitory influence of tactile inputs on corticospinal excitability was diminished. Our findings highlight the spatial specificity of tactile inputs in influencing corticospinal excitability. Moreover, we suggest that tactile inputs distinctly modulate M1's excitatory and inhibitory pathways, with S1 being crucial in facilitating tactile-motor integration.

Population Balance Equations for Reactive Separation in Polymer Upcycling.

Many polymer upcycling efforts aim to convert plastic waste into high-value liquid hydrocarbons. However, the subsequent cleavage of middle distillates to light gases can be problematic. The reactor often contains a vapor phase (light gases and middle distillates) and a liquid phase (molten polymers and waxes with a suspended or dissolved catalyst). Because the catalyst resides in the liquid phase, middle distillates that partition into the vapor phase are protected against further cleavage into light gases. In this paper, we consider a simple reactive separation strategy, in which a gas outflow removes the volatile products as they form. We combine vapor-liquid equilibrium models and population balance equations (PBEs) to describe polymer upcycling in a two-phase semibatch reactor. The results suggest that the temperature, headspace volume, and flow rate of the reactor can be used to tune selectivity toward the middle distillates, in addition to the molecular mechanism of catalysis. We anticipate that two-phase reactor models will be important in many polymer upcycling processes and that reactive separation strategies will provide ways to boost the yield of the desired products in these cases.

Supported Platinum Nanoparticles Catalyzed Carbon-Carbon Bond Cleavage of Polyolefins: Role of the Oxide Support Acidity.

Supported platinum nanoparticle catalysts are known to convert polyolefins to high-quality liquid hydrocarbons using hydrogen under relatively mild conditions. To date, few studies using platinum grafted onto various metal oxide (MxOy) supports have been undertaken to understand the role of the acidity of the oxide support in the carbon-carbon bond cleavage of polyethylene under consistent catalytic conditions. Specifically, two Pt/MxOy catalysts (MxOy = SrTiO3 and SiO2-Al2O3; Al = 3.0 wt %, target Pt loading 2 wt % Pt ∼1.5 nm), under identical catalytic polyethylene hydrogenolysis conditions (T = 300 °C, P(H2) = 170 psi, t = 24 h; Mw = ∼3,800 g/mol, Mn = ∼1,100 g/mol, D = 3.45, Nbranch/100C = 1.0), yielded a narrow distribution of hydrocarbons with molecular weights in the range of lubricants (Mw = < 600 g/mol; Mn < 400 g/mol; D = 1.5). While Pt/SrTiO3 formed saturated hydrocarbons with negligible branching, Pt/SiO2-Al2O3 formed partially unsaturated hydrocarbons (<1 mol % alkenes and ∼4 mol % alkyl aromatics) with increased branch density (Nbranch/100C = 5.5). Further investigations suggest evidence for a competitive hydrocracking mechanism occurring alongside hydrogenolysis, stemming from the increased acidity of Pt/SiO2-Al2O3 compared to Pt/SrTiO3. Additionally, the products of these polymer deconstruction reactions were found to be independent of the polyethylene feedstock, allowing the potential to upcycle polyethylenes with various properties into a value-added product.

Memory consolidation of sequence learning and dynamic adaptation during wakefulness.

Motor learning involves acquiring new movement sequences and adapting motor commands to novel conditions. Labile motor memories, acquired through sequence learning and dynamic adaptation, undergo a consolidation process during wakefulness after initial training. This process stabilizes the new memories, leading to long-term memory formation. However, it remains unclear if the consolidation processes underlying sequence learning and dynamic adaptation are independent and if distinct neural regions underpin memory consolidation associated with sequence learning and dynamic adaptation. Here, we first demonstrated that the initially labile memories formed during sequence learning and dynamic adaptation were stabilized against interference through time-dependent consolidation processes occurring during wakefulness. Furthermore, we found that sequence learning memory was not disrupted when immediately followed by dynamic adaptation and vice versa, indicating distinct mechanisms for sequence learning and dynamic adaptation consolidation. Finally, by applying patterned transcranial magnetic stimulation to selectively disrupt the activity in the primary motor (M1) or sensory (S1) cortices immediately after sequence learning or dynamic adaptation, we found that sequence learning consolidation depended on M1 but not S1, while dynamic adaptation consolidation relied on S1 but not M1. For the first time in a single experimental framework, this study revealed distinct neural underpinnings for sequence learning and dynamic adaptation consolidation during wakefulness, with significant implications for motor skill enhancement and rehabilitation.