Explicit Mechanism Research Articles

Contesting Caste: Institutionalized Oppression and Circumventive Legal Resistance

Abstract Across the globe, people who mobilize to protect their rights in highly oppressive contexts may have to navigate government institutions that not only fail to implement protections but also engage in discriminatory practices. This article introduces the term “circumventive legal resistance” to describe practices of making legally grounded claims but facilitating relief through processes of expression and negotiation that are distinct from explicit mechanisms of legal enforcement. Based upon a study of twenty-seven rural, semi-rural, and urban areas across the north and north-west regions of India, this article documents how Dalit women—from the most marginalized groups at the base of the caste pyramid—mobilize to protect their rights in contexts where local institutions do not enforce laws prohibiting caste discrimination and instead perpetrate caste-based forced labor practices. In particular, I focus on a campaign to end manual scavenging—a form of caste-based forced labor that is one of the worst surviving symbols of untouchability. With local channels to legal relief largely foreclosed, Dalit women who leave manual scavenging engage in circumventive legal resistance: they draw on law to make claims but win relief through avenues distinct from those envisioned within the parameters of the law.

Land covers associated with forest expansion hot spots in the Nepal Himalaya

Abstract Many regions of the Himalaya are experiencing forest expansion, signifying a widespread forest transition across this fragile mountain system. In the Nepal Himalaya, forest expansion is increasingly attributed to the narrative of cropland abandonment driven by rural outmigration. Understanding forest change dynamics as consequences of land use changes is critical in the context of rural mountain societies such as Nepal, which exhibit complex interactions between forest, agriculture, and livelihoods. We analysed forest gain in Nepal from 2000–2019 to inquire where and when forests have expanded and what land covers transitioned into forests. We integrated spatiotemporal analysis of national land cover maps and photointerpretation of very high resolution (VHR) imagery to improve analytical estimates. The Middle Mountain physiographic region experienced the strongest hot spots of forest gains relative to the high mountains or lowlands. Visual interpretation of VHR showed that 68.8% of forest gains since 2000 occurred on shrubland, and 26.5% on cropland. The dominance of shrubland-forest transitions implied that shrubland is an intermediate stage in a multi-decadal succession process, or a semi-permanent state such as arrested succession. Notably however, we also detected cropland-forest transitions occurring as fast as 6–10 years, indicating the potential for rapid forest succession if biophysical conditions permit. Thus, variations in land cover transitions to forests in the hills implicated multiple pathways of forest regeneration, reflecting a variety of spatiotemporally explicit drivers. Our results differ from previous studies because VHR image analysis accounted for land cover classification errors and improved land cover quantification. Further research on spatially explicit mechanisms and drivers of forest gain are needed to understand the synergies of forest, agriculture, and livelihoods to inform land use land cover policies that could be leveraged to enhance rural mountain livelihoods.

Energetics explain predator occurrence and movement in pyrodiverse landscapes

ContextFire-adapted species have evolved to exploit resources in heterogenous landscapes that presumably maximize energy acquisition and minimize energetic expenditure. However, limited empirical work exists demonstrating the explicit energetic mechanisms that drive such adaptive responses to fire across diverse landscapes.ObjectivesThe California spotted owl (Strix occidentalis occidentalis) appears to benefit from landscape heterogeneity and preferentially uses smaller patches of severely burned forest, a behavior that has been hypothesized as adaptive. Here, we investigate empirical support for this hypothesis.MethodsWe leveraged high-resolution GPS tracking and nest video monitoring to examine the hunting success, movement, and nest provisioning of 34 spotted owls in the Sierra Nevada and San Bernardino Mountains, California across burned and unburned landscapes.ResultsRegardless of time since fire, individuals avoided foraging directly within moderately or severely burned patches. 1 to 2 years post-fire, individuals had more success capturing prey in unburned forest, and the energy individuals spent moving increased with the proportion of high-severity fire and decreased with the proportion unburned forest. Multiple years after a fire, individuals had more success capturing prey, spent less energy moving, and provisioned more energy to nests in landscapes with more low-severity fire.ConclusionsThese results support the hypothesis that spotted owls are adapted to fire-prone landscapes and that disturbance events within this region’s natural range of variation can ultimately promote hunting and provisioning. As fires deviate from regional norms across the globe, the negative impacts of fire may become more extreme and long-term benefits of fire may degrade for animals in fire-prone landscapes. Examining the mechanistic impacts of disturbance can allow us to better understand animal responses to rapidly changing landscapes.

Dual Polarization of Ni Sites at VOx-Ni3N Interface Boosts Ethanol Oxidation Reaction.

Substituting thermodynamically favorable ethanol oxidation reaction (EOR) for oxygen evolution reaction (OER) engenders high-efficiency hydrogen production and generates high value-added products as well. However, the main obstacles have been the low activity and the absence of an explicit catalytic mechanism. Herein, a heterostructure composed of amorphous vanadium oxide and crystalline nickel nitride (VOx-Ni3N) is developed. The heterostructure immensely boosts the EOR process, achieving the current density of 50mA cm-2 at the low potential of 1.38V versus reversible hydrogen electrode (RHE), far surpassing the sluggish OER (1.65V vs RHE). Electrochemical impedance spectroscopy indicates that the as-fabricated heterostructure can promote the adsorption of OH- and the generation of the reactive species (O*). Theoretical calculations further outline the dual polarization of the Ni site at the interface, specifically the asymmetric charge redistribution (interfacial polarization) and in-plane polarization. Consequently, the dual polarization modulates the d-band center, which in turn regulates the adsorption/desorption strength of key reaction intermediates, thereby facilitating the entire EOR process. Moreover, a VOx-Ni3N-based electrolyzer, coupling hydrogen evolution reaction (HER) and EOR, attains 50mA cm-2 at a low cell voltage of ≈1.5V. This work thus paves the way for creating dual polarization through interface engineering toward broad catalysis.

Femoral version and its clinical relevance in adult hip preservation surgery for developmental dysplasia of the hip.

Femoral version (FV) is more widely adopted with the definition as the angle between the long axis of the femoral neck and the tangent line of the posterior femoral condyles on the axial plane, and the normal range between 5 and 20°. FV can be measured by imaging and functional tests. Cross-sectional CT including both the hip and the knee is the typically used imaging technique, yet variation exists according to the different landmarks used. As MRI investigations are routinely performed preoperatively, and protocols can be easily adopted to include version measurement, they are frequently used as an alternative to CT and offers several advantages. Abnormal FV has adverse effects on the biomechanics and musculoskeletal health of the whole lower limb. It affects the lever arm of muscles and the forces that the hip and patellofemoral joints suffer, and can lead to disorders such as osteoarthritis and impingement. In adult hip preservation surgery for developmental dysplasia of the hip (DDH), abnormal FV is sometimes accompanied by other morphological abnormities of the hip, a more severe DDH, and can help predict postoperative range of motion (ROM), and postoperative impingement. Currently, the most frequently used surgical technique for abnormal FV is femoral derotational osteotomy. Many controversies are left to be solved, including the specific origin of FV, the indication for femoral derotational osteotomy, especially in patients with combined DDH and abnormal FV, and the explicit compensation mechanism of abnormal FV by tibial torsion.

Functional determinants of lysophospholipid- and voltage-dependent regulation of TRPC5 channel

Lysophosphatidylcholine (LPC) is a bioactive lipid present at high concentrations in inflamed and injured tissues where it contributes to the initiation and maintenance of pain. One of its important molecular effectors is the transient receptor potential canonical 5 (TRPC5), but the explicit mechanism of the activation is unknown. Using electrophysiology, mutagenesis and molecular dynamics simulations, we show that LPC-induced activation of TRPC5 is modulated by xanthine ligands and depolarizing voltage, and involves conserved residues within the lateral fenestration of the pore domain. Replacement of W577 with alanine (W577A) rendered the channel insensitive to strong depolarizing voltage, but LPC still activated this mutant at highly depolarizing potentials. Substitution of G606 located directly opposite position 577 with tryptophan rescued the sensitivity of W577A to depolarization. Molecular simulations showed that depolarization widens the lower gate of the channel and this conformational change is prevented by the W577A mutation or removal of resident lipids. We propose a gating scheme in which depolarizing voltage and lipid-pore helix interactions act together to promote TRPC5 channel opening.

Restoration of Radiosensitivity by Soya Isoflavone Genistein is Accomplished by Facilitating DNA Damage Response in Radioresistant Cervical Cancer in vitro

ABSTRACT Context: Enhancing radiotherapeutic efficacy in tumor cells and sparing the normal tissues are major clinical concerns for the betterment of cancer therapy. Genistein (GEN) being a radiosensitizer ameliorates the effectiveness of radiation-induced cell killing by inducing DNA damage. This molecule is accountable for minimizing radiation-related toxicity and protecting healthy cells. However, the explicit mechanism of action of such molecules needs exploration. Aims: The objective of this study is to investigate the mechanistic action of GEN in cervical cancer cell radiosensitization. Settings and Design: Cervical squamous carcinoma cell SiHa and a radioresistant subline SiHa/RR (developed and isolated from SiHa) were taken for this study. The experiments were performed by pretreating the cells with IC30 dose of GEN, followed by acute irradiation to detect the impact of GEN in imparting radiosensitivity. Subjects and Methods: Optimal dose selection of GEN was performed by MTT assay, and radiosensitizing potency was determined by pretreating the cells with IC30 dose of GEN, followed by challenging with acute incremental doses of radiation. Mechanistic parameters were checked by clonogenic assay, cell cycle analysis, DNA damage estimation, apoptosis, and wound healing-sphere-forming assay. Statistical Analysis Used: Statistical analysis was performed in GraphPad software by performing the Student’s t-test. Results: Results depicted decreased numbers of colonies, increased frequency of DNA damage and apoptotic cells, and suppressed wound healing ability along with restrained sphere-forming ability upon the intervention of cells with GEN before radiation exposure. Such observations implied that GEN pretreatment renders improved radiosensitivity in cervical cancer by increased DNA damage-mediated G2/M arrest with subsequent apoptosis. Conclusions: GEN by inducing DNA damage stimulates radiation-induced cell killing in vitro.

The US-China BIT: Enhancing Dispute Settlement Mechanism

This article critically examines the inadequacies of the International Centre for Settlement of Investment Disputes (ICSID) and the intricacies surrounding the divergent strategies employed by the United States and China in managing investor-state disputes. Given the lack of an explicit dispute resolution mechanism in the envisioned US-China Bilateral Investment Treaty (BIT), the paper advocates for a comprehensive strategy for shaping future agreements. It proposes integrating UNCITRAL Arbitration Rules as an alternative to ICSID; the inclusion of ad hoc Arbitration Panels is recommended for tailored resolutions; and the incorporation of alternative dispute resolution (ADR) mechanisms as pre-arbitration procedures is emphasized. This multifaceted strategy aims to address the deficiencies of a singular arbitration mechanism and foster a more adaptable and effective dispute resolution framework tailored to the specific needs of China and the United States, providing a balanced means of addressing the complexities inherent in investor-state disputes.

A Multidimensional Neural Representation of Face Impressions.

From a glimpse of a face, people form trait impressions that operate as facial stereotypes, which are largely inaccurate yet nevertheless drive social behavior. Behavioral studies have long pointed to dimensions of trustworthiness and dominance that are thought to underlie face impressions due to their evolutionarily adaptive nature. Using human neuroimaging (N = 26, 19 female, 7 male), we identify a two-dimensional representation of faces' inferred traits in the middle temporal gyrus (MTG), a region involved in domain-general conceptual processing including the activation of social concepts. The similarity of neural-response patterns for any given pair of faces in the bilateral MTG was predicted by their proximity in trustworthiness-dominance space, an effect that could not be explained by mere visual similarity. This MTG trait-space representation occurred automatically, was relatively invariant across participants, and did not depend on the explicit endorsement of face impressions (i.e., beliefs that face impressions are valid and accurate). In contrast, regions involved in high-level social reasoning (the bilateral temporoparietal junction and posterior superior temporal sulcus; TPJ-pSTS) and entity-specific social knowledge (the left anterior temporal lobe; ATL) also exhibited this trait-space representation but only among participants who explicitly endorsed forming these impressions. Together, the findings identify a two-dimensional neural representation of face impressions and suggest that multiple implicit and explicit mechanisms give rise to biases based on facial appearance. While the MTG implicitly represents a multidimensional trait space for faces, the TPJ-pSTS and ATL are involved in the explicit application of this trait space for social evaluation and behavior.

Taking Photoacoustic Force into Account in Liquid-Phase Peak Force Infrared Microscopy.

The microscopic structure of the material's solid-liquid interface significantly influences its physicochemical properties. Peak force infrared microscopy (PFIR) is a powerful technique for analyzing these interfaces at the nanoscale, revealing crucial structure-activity relationships. PFIR is recognized for its explicit photothermal signal generation mechanism but tends to overlook other photoinduced forces, which can disturb the obtained infrared spectra, thereby reducing spectral signal-to-noise ratio (SNR) and sensitivity. We have developed a multiphysics-coupled theoretical model to assess the magnitudes of various photoinduced forces in PFIR experiments and have found that the magnitude of the photoacoustic force is comparable to that of the photothermal expansion force in a liquid environment. Our calculations show that through simple modulation of the pulse waveform it is possible to effectively suppress the photoacoustic interference, thereby improving the SNR and sensitivity of PFIR. This work aims to alert researchers to the potential for strong photoacoustic interference in liquid-phase PFIR measurements and enhance the performance of PFIR by clarifying the photoinduced forces entangled in the signals.

Implicit and Explicit Sequence Learning in Adults With Developmental Language Disorder.

Developmental language disorder (DLD) is a neurodevelopmental disorder that impacts approximately 7% of the population and is characterized by unexplained deficits in expressive and/or receptive components of language. A common procedural learning task, serial reaction time (SRT), has been used to develop models of the basis of DLD. However, paradigms involve differing levels of implicit and explicit learning during this task, muddying interpretations of the data. Here, we tested adults with DLD on implicit and explicit SRT tasks to better understand implicit and explicit procedural learning in this population. We hypothesized that adults with DLD would demonstrate reduced learning on only the implicit SRT task, as alternate explicit neural mechanisms could lead to equivalent performance on the explicit task. Fifty participants (25 with DLD and 25 with typical language) completed implicit and explicit SRT tasks, measuring their ability to learn visually presented 10-element sequences. Group differences were evaluated on sequence learning, error rates, and explicit recall of the sequence after learning. Sequence learning was the same between the groups on both tasks. However, individuals with DLD showed increased errors and significantly worse recall of the explicitly learned sequence. Results suggest that sequence learning may be intact in this population, while aspects of explicit learning and motoric responses are impaired. Results are interpreted in light of a neurobiological model of DLD. https://doi.org/10.23641/asha.26210651.

Joint experimental-computational: Revealing the role of sodium poly(heptazineimide) in the selective separation of CO2 in PEBAX-based mixed matrix membranes

Mixed matrix membranes (MMMs) with the dual properties of porous materials and polymer matrix membranes have become one of the most optimal solutions to the gas separation problem. However, the adapted porous material and the explicit transport mechanism of gases within the mixed matrix membrane hinder its further commercialization. Thanks to their porous nature and tunable gas adsorption properties, heteroatom-doped porous materials, especially nitrogen-doped porous materials, are widely used to design and prepare advanced CO2 separation membranes. Herein, a layered two-dimensional nano-sheet with a nitrogen content of 44.7 % was successfully synthesized via thermal polymerization. And nano-sheets were homogeneously dispersed in a Pebax matrix to make a composite film. Since the CO2 affinity of the nitrogen functional site and the PEO flexible chain, realizing the synergistic improvement of CO2 permeability and selectivity. A comprehensive combined permeation experimental/simulation characterization reveals the CO2 transport pathway within the membrane, indicating the mechanism of action of nitrogen-doped porous packing on CO2 diffusion. Among these, the CO2 permeability of the mixed matrix film containing 5 wt% sodium poly(heptazine imide) (NaPHI) reached 153 Barrer at a feed gas pressure of 9 bar, nearly 149 % compared to the pure Pebax film. The selectivity of CO2/N2 was enhanced to 105, exhibiting a remarkable increase of 159 % and exceeding the 2019 Robeson limit. Importantly, the present work further reveals and demonstrates the gas separation mechanism of nitrogen-doped porous filler/polymer hybrid matrix membranes, which provides new ideas for the design and application of heteroatom-doped porous fillers in the field of gas separation.

Early childhood development strategy for the world's children with disabilities.

Early childhood is foundational for optimal and inclusive lifelong learning, health and well-being. Young children with disabilities face substantial risks of sub-optimal early childhood development (ECD), requiring targeted support to ensure equitable access to lifelong learning opportunities, especially in low- and middle-income countries. Although the Sustainable Development Goals, 2015-2030 (SDGs) emphasise inclusive education for children under 5 years with disabilities, there is no global strategy for achieving this goal since the launch of the SDGs. This paper explores a global ECD framework for children with disabilities based on a review of national ECD programmes from different world regions and relevant global ECD reports published since 2015. Available evidence suggests that any ECD strategy for young children with disabilities should consists of a twin-track approach, strong legislative support, guidelines for early intervention, family involvement, designated coordinating agencies, performance indicators, workforce recruitment and training, as well as explicit funding mechanisms and monitoring systems. This approach reinforces parental rights and liberty to choose appropriate support pathway for their children. We conclude that without a global disability-focussed ECD strategy that incorporates these key features under a dedicated global leadership, the SDGs vision and commitment for the world's children with disabilities are unlikely to be realised.

INCENTIVE MECHANISMS OF AN EXPERIMENTAL RESOURCE-SHARING PLATFORM CONSIDERING REPUTATION EFFECTS FOR MEGAPROJECTS

Participating in megaproject experimental tasks would significantly improve the laboratories’ industry influence and future competitiveness. Thus, this paper introduces the long-term reputation effects of the incentive model of an experimental resource-sharing platform for megaprojects, which could motivate them to consider future benefits and improve their current efforts. The aim is to incentivize laboratories’ resource-sharing behavior more effectively and to increase the amount of resources shared by these laboratories on the platform, thus guaranteeing the long-term sustainability of the platform. It constructs the incentive model by combining dual implicit and explicit incentive mechanisms. It analyses the incentive mechanism of a reputation effect on laboratories compared with the pure explicit mechanism so that the primary conditions for reputation incentives can be obtained to achieve Pareto improvement. Finally, the proposed method is validated in combination with data simulation. The results show that although dual implicit and explicit incentive mechanisms could reduce the information asymmetry between the two sides and increase the efforts of laboratories and the benefits of the platform, the platform should not blindly increase the intensity of these incentives and need to consider the influence of the subsidies of these laboratories’ upfront inputs, the degree of sharing and their informatization capabilities.

Organismal trade-offs and the pace of planktonic life.

No one is perfect, and organisms that perform well in some habitat or with respect to some tasks, do so at the cost of performance in others: there are inescapable trade-offs. Organismal trade-offs govern the structure and function of ecosystems and attempts to demonstrate and quantify trade-offs have therefore been an important goal for ecologists. In addition, trade-offs are a key component in trait-based ecosystem models. Here, I synthesise evidence of trade-offs in plankton organisms, from bacteria to zooplankton, and show how a slow-fast gradient in life histories emerges. I focus on trade-offs related to the main components of an organism's Darwinian fitness, that is resource acquisition, survival, and propagation. All consumers need to balance the need to eat without being eaten, and diurnal vertical migration, where zooplankton hide at depth during the day to avoid visual predators but at the cost of missed feeding opportunities in the productive surface layer, is probably the best documented result of this trade-off. However, there are many other more subtle but equally important behaviours that similarly are the result of an optimisation of these trade-offs. Most plankton groups have also developed more explicit defence mechanisms, such as toxin production or evasive behaviours that are harnessed in the presence of their predators; the costs of these have often proved difficult to quantify or even demonstrate, partly because they only materialise under natural conditions. Finally, all multicellular organisms must allocate time and resources among growth, reproduction, and maintenance (e.g. protein turnover and DNA repair), and mate finding may compromise both survival and feeding. The combined effects of all these trade-offs is the emergence of a slow-fast gradient in the pace-of-life, likely the most fundamental principle for the organisation of organismal life histories. This crystallisation of trade-offs may offer a path to further simplification of trait-based models of marine ecosystems.

Dual roles of the inorganic aqueous phase on secondary organic aerosol growth from benzene and phenol

Abstract. Benzene, emitted from automobile exhaust and biomass burning, is ubiquitous in ambient air. Benzene is a precursor hydrocarbon (HC) that forms secondary organic aerosol (SOA), but its SOA formation mechanism is not well studied. To accurately predict the formation of benzene SOA, it is important to understand the gas mechanisms of phenol, which is one of the major products formed from the atmospheric oxidation of benzene. Laboratory data presented herein highlight the impact of the aqueous phase on SOA generated through benzene and phenol oxidation. The roles of the aqueous phase consist of (1) suppression of the aging of hydrocarbon and (2) conventional acid-catalyzed reactions in the inorganic phase. To explain this unusual effect, it is hypothesized that a persistent phenoxy radical (PPR) effectively forms via a heterogeneous reaction of phenol and phenol-related products in the presence of wet inorganic aerosol. These PPR species are capable of catalytically consuming ozone during an NOx cycle and negatively influencing SOA growth. In this study, explicit gas mechanisms were derived to produce the oxygenated products from the atmospheric oxidation of phenol or benzene. Gas mechanisms include the existing Master Chemical Mechanism (MCM v3.3.1), the reaction path for peroxy radical adducts originating from the addition of an OH radical to phenols forming low-volatility products (e.g., multi-hydroxy aromatics), and the mechanisms to form heterogeneous production of PPR. The simulated gas products were classified into volatility- and reactivity-based lumped species and incorporated into the Unified Partitioning Aerosol Reaction (UNIPAR) model that predicts SOA formation via multiphase reactions of phenol or benzene. The predictability of the UNIPAR model was examined using chamber data, which were generated for the photooxidation of phenol or benzene under controlled experimental conditions (NOx levels, humidity, and inorganic seed types). The SOA formation from both phenol and benzene still increased in the presence of wet inorganic seed because of the oligomerization of reactive organic species in the aqueous phase. However, model simulations show a significant suppression of ozone, the oxidation of phenol or benzene, and SOA growth compared with those without PPR mechanisms. The production of PPR is accelerated in the presence of acidic aerosol and this weakens SOA growth. In benzene oxidation, up to 53 % of the oxidation pathway is connected to phenol formation in the reported gas mechanism. Thus, the contribution of PPR to gas mechanisms is less than that of phenol. Overall, SOA growth in phenol or benzene is negatively related to NOx levels in the high-NOx region (HC ppbC / NOx ppb < 5). However, the simulation indicates that the significance of PPR rises with decreasing NOx levels. Hence, the influence of NOx levels on SOA formation from phenol or benzene is complex under varying temperature and seed type conditions. Adding the comprehensive reaction of phenolic compounds will improve the prediction of SOA formation from aromatic HCs due to the missing mechanisms in the current air quality model.

ICAM-1 may promote the loss of dopaminergic neurons by regulating inflammation in MPTP-induced Parkinson’s disease mouse models

Parkinson’s disease (PD) is a chronic neurodegenerative disease with unclear pathogenesis that involves neuroinflammation and intestinal microbial dysbiosis. Intercellular adhesion molecule-1 (ICAM-1), an inflammatory marker, participates in neuroinflammation during dopaminergic neuronal damage. However, the explicit mechanisms of action of ICAM-1 in PD have not been elucidated. We established a subacute PD mouse model by the intraperitoneal injection of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and observed motor symptoms and gastrointestinal dysfunction in mice. Immunofluorescence was used to examine the survival of dopaminergic neurons, expression of microglial and astrocyte markers, and intestinal tight junction-associated proteins. Then, we use 16 S rRNA sequencing to identify alterations in the microbiota. Our findings revealed that ICAM-1-specific antibody (Ab) treatment relieved behavioural defects, gastrointestinal dysfunction, and dopaminergic neuronal death in MPTP-induced PD mice. Further mechanistic investigations indicated that ICAM-1Ab might suppress neuroinflammation by inhibiting the activation of astrocytes and microglia in the substantia nigra and relieving colon barrier impairment and intestinal inflammation. Furthermore, 16 S rRNA sequencing revealed that the relative abundances of bacterial Firmicutes, Clostridia, and Lachnospiraceae were elevated in the PD mice. However, ICAM-1Ab treatment ameliorated the MPTP-induced disorders in the intestinal microbiota. Collectively, we concluded that the suppressing ICAM-1 might lead to the a significant decrease of inflammation and restore the gut microbial community, thus ameliorating the damage of DA neurons.

Modeling the influence of carbon branching structure on secondary organic aerosol formation via multiphase reactions of alkanes

Abstract. Branched alkanes represent a significant proportion of hydrocarbons emitted in urban environments. To accurately predict the secondary organic aerosol (SOA) budgets in urban environments, these branched alkanes should be considered as SOA precursors. However, the potential to form SOA from diverse branched alkanes under varying environmental conditions is currently not well understood. In this study, the Unified Partitioning Aerosol Phase Reaction (UNIPAR) model is extended to predict SOA formation via the multiphase reactions of various branched alkanes. Simulations with the UNIPAR model, which processes multiphase partitioning and aerosol-phase reactions to form SOA, require a product distribution predicted from an explicit gas kinetic mechanism, whose oxygenated products are applied to create a volatility- and reactivity-based αi species array. Due to a lack of practically applicable explicit gas mechanisms, the prediction of the product distributions of various branched alkanes was approached with an innovative method that considers carbon lengths and branching structures. The αi array of each branched alkane was primarily constructed using an existing αi array of the linear alkane with the nearest vapor pressure. Generally, the vapor pressures of branched alkanes and their oxidation products are lower than those of linear alkanes with the same carbon number. In addition, increasing the number of alkyl branches can also decrease the ability of alkanes to undergo autoxidation reactions that tend to form low-volatility products and significantly contribute to alkane SOA formation. To account for this, an autoxidation reduction factor, as a function of the degree and position of branching, was applied to the lumped groups that contain autoxidation products. The resulting product distributions were then applied to the UNIPAR model for predicting branched-alkane SOA formation. The simulated SOA mass was compared to SOA data generated under varying experimental conditions (i.e., NOx levels, seed conditions, and humidity) in an outdoor photochemical smog chamber. Branched-alkane SOA yields were significantly impacted by NOx levels but insignificantly impacted by seed conditions or humidity. The SOA formation from branched and linear alkanes in diesel fuel was simulated to understand the relative importance of branched and linear alkanes with a wide range of carbon numbers. Overall, branched alkanes accounted for a higher proportion of SOA mass than linear alkanes due to their higher contribution to diesel fuel.

High-Fat-High-Fructose Diet Elicits Brown Adipocyte Dysfunction through miRNA-103 Induced miRNA Biogenesis Pathway

Background: Obesity is a critical public health concern with its prevalence growing at an alarming rate worldwide. The Western diet that typically includes high-fat or high-fructose components is one of the leading contributing factors of obesity. Recent findings demonstrate the essential role of BAT in regulating whole-body metabolism. However, the explicit mechanism through which BAT maintains homeostasis is still unknown. Methods: Six-week-old C57BL/6 male mice were fed either a low-fat diet (LFD) or a high-fat high-fructose diet (HFHFD) for 4, 12, and 20 weeks. Results: We observed a significant increase in BAT weight under HFHFD along with BAT whitening in a time-dependent manner. This was also accompanied by a significant decrease in UCP1 and PGC1α protein, as well as a significant increase in the Bax/Bcl-2 ratio as early as 12 weeks, indicating increased apoptosis under HFHFD. Interestingly, miRNA-103 expression that holds a seed sequence within the miRNA biogenesis machinery, Dicer, was significantly upregulated after 12 and 20 weeks of HFHFD. Dicer and another biogenesis regulator, TRBP2, exhibited significant upregulation at 4 weeks of HFHFD. Conversely, those gene expressions were significantly downregulated at 12 and 20 weeks of HFHFD, followed by a significant decrease in the protein level at 12 weeks. To confirm the mechanistic connection, miRNA-103 knockdown in vitro significantly upregulated Dicer and the TRBP2 gene. However, only Dicer exhibited a significant increase at the translational level. Conclusion: Overall, we conclude that HFHFD may elicit BAT dysfunction by inhibiting Dicer via miRNA-103.

MST-GAT: A multi-perspective spatial-temporal graph attention network for multi-sensor equipment remaining useful life prediction

Graph neural networks (GNNs) have been applied as an emerging technique for remaining useful life (RUL) prediction due to their ability to effectively exploit the dependencies between multi-sensor data. Despite existing GNN-based RUL prediction methods have achieved promising results, they do not consider the spatial-temporal dependencies of multi-sensor data from different perspectives (global and local), making it difficult to fully utilize the useful information in multi-sensor data. Secondly, traditional point prediction method can only provide the possible future RUL prediction value, but cannot quantify the uncertainty of RUL prediction, making it difficult to provide more information for decision-making. To address the above challenges, we propose a multi-perspective spatial-temporal graph attention network (MST-GAT) for multi-sensor equipment RUL prediction. MST-GAT constructs a multi-perspective graph attention network (MP-GAT) and a temporal convolutional network (TCN) to capture complex spatial-temporal dependencies in multi-sensor data. Specifically, MP-GAT employs a multi-head self-attention mechanism and two multi-head explicit sparse self-attention mechanisms to explicitly model global and local spatial dependencies, and feeds multi-perspective spatial information into TCN to capture temporal dependencies. Furthermore, a joint optimization network is constructed for predicting RUL and its prediction interval to quantify uncertainty. Experiments on three benchmark datasets demonstrate that MST-GAT outperforms state-of-the-art baselines in RUL prediction and can accurately quantify uncertainty.