Bidirectional Effects Research Articles

Altered effective connectivity between reward and inhibitory control networks in people with binge eating episodes: A spectral dynamic causal modeling study

BackgroundConverging evidence points to the crucial role of brain connectivity involved in aberrant behavioral control and reward reactivity in the onset and maintenance of binge eating. However, the directional interaction pattern between brain's reward and inhibitory control systems in people with binge eating episodes is largely unknown. MethodsResting-state fMRI data were collected from 36 adults with binge eating episodes (age: 19.05 ± 0.90) and 36 well-matched controls (age: 18.88 ± 0.78). We applied spectral dynamic causal modeling approach to estimate effective connectivity of the executive control network (ECN) and reward network (RN) with 15 predefined regions of interest, and investigate the between-group differences in directional connectivity. ResultsCompared with controls, the positive connections within the ECN were significantly strengthened in individuals with binge eating episodes, while the negative connections from the ECN to RN and from the RN to ECN were significantly weakened. In adults with binge eating episodes, the RN→ECN connectivity was positively related to binge frequency even controlling for age, sex, and body mass index. ConclusionThis study represents an important first step in addressing the role of directional integration between reward and inhibitory control networks in binge eating, and provides novel evidence that the ability of people with binge eating episodes to maintain a balance between inhibitory control and reward reactivity is decreased, as reflected by diminished bidirectional negative effects of prefrontal-subcortical circuitry at rest.

Observational and Genetic Evidence for Bidirectional Effects Between Red Blood Cell Traits and Diastolic Blood Pressure.

Previous studies have found associations of red blood cell (RBC) traits (hemoglobin and RBC count) with blood pressure; whether these associations are causal is unknown. We performed cross-sectional analyses in the Lifelines Cohort Study (n = 167,785). Additionally, we performed bidirectional 2 sample Mendelian randomization (MR) analyses to explore the causal effect of the 2 traits on systolic (SBP) and diastolic blood pressure (DBP), using genetic instrumental variables regarding hemoglobin and RBC identified in UK Biobank (n = 350,475) and International Consortium of Blood Pressure studies for SBP and DBP (n = 757,601). In cross-sectional analyses, we observed positive associations with hypertension and blood pressure for both hemoglobin (odds ratio [OR] = 1.18, 95% confidence interval [CI]: 1.16-1.20 for hypertension; B = 0.11, 95% CI: 0.11-0.12 for SBP; B = 0.11, 95% CI: 0.10-0.11 for DBP, all per SD) and RBC (OR = 1.14, 95% CI: 1.12-1.16 for hypertension; B = 0.11, 95% CI: 0.10-0.12 for SBP; B = 0.08, 95% CI: 0.08-0.09 for DBP, all per SD). MR analyses suggested that higher hemoglobin and RBC cause higher DBP (inverse-variance weighted B = 0.11, 95% CI: 0.07-0.16 for hemoglobin; B = 0.07, 95% CI: 0.04-0.10 for RBC, all per SD). Reverse MR analyses (all per SD) suggested causal effects of DBP on both hemoglobin (B = 0.06, 95% CI: 0.03-0.09) and RBC (B = 0.08, 95% CI: 0.04-0.11). No significant effects on SBP were found. Our results suggest bidirectional causal relationships of hemoglobin and RBC with DBP, but not with SBP.

The potential role of cholesterol in Parkinson's disease neuropathology: perpetrator or victim.

Parkinson's disease (PD) is a neurodegenerative disease characterized by deposition of α-synuclein and aggregation of Lewy bodies. Cholesterol is involved with PD neuropathology in bidirectional ways that could be protective or harmful. Thus, the objective of the present review was to verify the potential role of cholesterol in PD neuropathology. Deregulation of ion channels and receptors induced by cholesterol alteration suggests a possible mechanism for the neuroprotective effects of cholesterol against PD development. However, high serum cholesterol level increases PD risk indirectly by 27-hydroxycholesterol which induces oxidative stress, inflammation, and apoptosis. Besides, hypercholesterolemia triggers the accumulation of cholesterol in macrophages and immune cells leading to the release of pro-inflammatory cytokines with progression of neuroinflammation subsequently. Additionally, cholesterol increases aggregation of α-synuclein and induces degeneration of dopaminergic neurons (DN) in the substantia nigra (SN). Hypercholesterolemia may lead to cellular Ca2+ overload causing synaptic and the development of neurodegeneration. In conclusion, cholesterol has bidirectional effects on PD neuropathology and might be protective or harmful.

From childhood adversity to latent stress vulnerability in adulthood: the mediating roles of sleep disturbances and HPA axis dysfunction.

Childhood adversity is a prominent predisposing risk factor for latent stress vulnerability, expressed as an elevated likelihood of developing stress-related psychopathology upon subsequent exposure to trauma in adulthood. Sleep disturbances have emerged as one of the most pronounced maladaptive behavioral outcomes of childhood adversity and are also a highly prevalent core feature of stress-related psychopathology, including post-traumatic stress disorder (PTSD). After reviewing the extensive literature supporting these claims, the current review addresses the notion that childhood adversity-induced sleep disturbances may play a causal role in elevating individuals' stress vulnerability in adulthood. Corroborating this, sleep disturbances that predate adult trauma exposure have been associated with an increased likelihood of developing stress-related psychopathology post-exposure. Furthermore, novel empirical evidence suggests that sleep disturbances, including irregularity of the sleep-wake cycle, mediate the link between childhood adversity and stress vulnerability in adulthood. We also discuss cognitive and behavioral mechanisms through which such a cascade may evolve, highlighting the putative role of impaired memory consolidation and fear extinction. Next, we present evidence to support the contribution of the hypothalamic-pituitary-adrenal (HPA) axis to these associations, stemming from its critical role in stress and sleep regulatory pathways. Childhood adversity may yield bi-directional effects within the HPA stress and sleep axes in which sleep disturbances and HPA axis dysfunction reinforce each other, leading to elevated stress vulnerability. To conclude, we postulate a conceptual path model from childhood adversity to latent stress vulnerability in adulthood and discuss the potential clinical implications of these notions, while highlighting directions for future research.

The role of EBV-encoded miRNA in EBV-associated gastric cancer.

Epstein-Barr virus (human herpesvirus 4, EBV) is a linear double-stranded DNA virus that infects over 90% of the population worldwide. However, our understanding of EBV's contribution to tumorigenesis of EBV-associated GC (EBVaGC) remains incomplete. Recent advancements in EBVaGC research have highlighted that EBV-encoded microRNAs (miRNAs) play prominent roles in critical cellular processes such as migration, cell cycle, apoptosis, cell proliferation, immune response, and autophagy. Notably, the largest group of EBV-encoded miRNAs, known as BamHI-A rightward transcripts (BARTs), exhibit bidirectional effects in EBVaGC. For instance, they present both anti-apoptotic and pro-apoptotic functions and enhance chemosensitivity while also conferring resistance to 5-fluorouracil. Despite these findings, the comprehensive mechanisms through which miRNAs contribute to EBVaGC are yet to be fully elucidated. In this work, we summarize the current evidence of the roles of miRNA in EBVaGC, particularly with the application of multi-omic techniques. Additionally, we discuss the application of miRNA in EBVaGC in retrospective analyses and provide novel perspectives on the use of miRNA in EBVaGC in translational medicine.

Longitudinal and bidirectional associations between posttraumatic stress disorder and emotional support among disaster-affected men and women.

Research has demonstrated a negative association between social support and symptoms of posttraumatic stress disorder (PTSD). This has been interpreted as a protective influence of social support against the development of posttraumatic stress symptoms (PTSS). Research on the opposite association is more limited, but findings suggest that PTSS have a negative impact on social support. There is conflicting evidence that these effects are moderated by gender. Few studies have assessed both associations and gender moderation in a postdisaster context. We examined the longitudinal and bidirectional effects of emotional support and PTSS and whether gender moderates these effects among U.S. survivors of the 2017-2018 season. Participants (N = 1,347) were assessed at four time points over 1 year. Bidirectional effects were assessed using cross-lagged, autoregressive analyses with the combined sample (Model 1) and grouped by gender (Model 2) to assess gender moderation. The results supported small bidirectional negative effects of social support and PTSS on one another from one assessment point (e.g. Wave 1) to the subsequent point (e.g., Wave 2) for all waves, βs = -.07-.15, p < .001-p = .040. Multigroup analyses suggested the effects were not significantly different by gender. Overall, the results suggest that social support and PTSS may mutually diminish one another. Such effects may result in a positive or negative cascade wherein high PTSS may lead to lower social support and, therefore, even higher PTSS and vice versa. These findings support the importance of including social support in interventions to promote PTSS prevention and recovery.

Bidirectional Mediation Effects between Intratumoral Microbiome and Host DNA Methylation Changes Contribute to Stomach Adenocarcinoma.

The induction of aberrant DNA methylation is the major pathway by which Helicobacter pylori infection induces stomach adenocarcinoma (STAD). The involvement of the non-H. pylori gastric microbiota in this mechanism remains to be examined. RNA sequencing data, clinical information, and DNA methylation data were obtained from The Cancer Genome Atlas (TCGA) STAD project. The Kraken 2 pipeline was employed to explore the microbiome profiles. The microbiome was associated with occurrence, distal metastasis, and prognosis, and differential methylation changes related to distal metastasis and prognosis were analyzed. Bi-directional mediation effects of the intratumoral microbiome and host DNA methylation changes on the metastasis and prognosis of STAD were identified by mediation analysis. The expression of the ZNF215 gene was verified by real-time quantitative PCR (RT-qPCR). A cell counting kit 8 (CCK8) cell proliferation experiment and a cell clone formation experiment were used to evaluate the proliferation and invasion abilities of gastric cells. Our analysis revealed that H. pylori and other cancer-related microorganisms were related to the occurrence, progression, or prognosis of STAD. The related methylated genes were particularly enriched in related cancer pathways. Kytococcus sedentarius and Actinomyces oris, which interacted strongly with methylation changes in immune genes, were associated with prognosis. Cell experiments verified that Staphylococcus saccharolyticus could promote the proliferation and cloning of gastric cells by regulating the gene expression level of the ZNF215 gene. Our study suggested that the bi-directional mediation effect between intratumoral microorganisms and host epigenetics was key to the distal metastasis of cancer cells and survival deterioration in the tumor microenvironment of stomach tissues of patients with STAD. IMPORTANCE The burgeoning field of oncobiome research declared that members of the intratumoral microbiome besides Helicobacter pylori existed in tumor tissues and participated in the occurrence and development of gastric cancer, and the methylation of host DNA may be a potential target of microbes and their metabolites. Current research focuses mostly on species composition, but the functional genes of the members of the microbiota are also key to their interaction with the host. Therefore, we focused on characterizing the species composition and functional gene composition of microbes in gastric cancer, and we suggest that microbes may further participate in the occurrence and development of cancer by influencing abnormal epigenetic changes in the host. Some key bioinformatics analysis results were verified by in vitro experiments. Thus, we consider that the tumor microbiota-host epigenetic axis of gastric cancer microorganisms and the host explains the mechanism of the microbiota participating in cancer occurrence and development, and we make some verifiable experimental predictions.

Asymmetrical facilitation ameliorates environmental conditions through positive feedback in partner traits

AbstractPositive species interactions, including facilitation and mutualism, are important in shaping ecological communities through the amelioration of stressful conditions. Facilitation results from traits (e.g., plant growth form) that create benefits for one or more interacting partners. The outcomes of facilitation depend on positive or negative feedbacks between partners, which can determine the stability of interactions over time. We can expand our understanding of these dynamics through a bidirectional approach that identifies the specific mechanisms creating benefits for the associated species, the traits related to those benefits, and the potential for feedbacks to affect amelioration by modifying traits. We characterized an association between the salt marsh plant Limonium carolinianum and mussel Geukensia sp. in the northern Gulf of Mexico. We used a field survey and three field experiments to establish the bidirectional effects of the association, the underlying mechanisms, and the relevant traits for each partner species. Mussels benefitted from Limonium canopies, which ameliorated high temperatures and predation for mussels, increasing survival and recruitment. These positive effects were particularly evident under larger canopies. Mussels enriched sediment organic matter and thus over time are expected to alleviate nutrient limitation for Limonium. Changes in functional traits of both species contributed to facilitation. Limonium both benefitted from and promoted higher mussel density, and mussels both allowed Limonium to grow or retain more leaves and benefitted from stress amelioration under larger canopies. The benefits of the association appear asymmetrical: mussels consistently benefitted in both experiments, but we found only modest positive effects on Limonium, and only over the longer term. These differences likely reflect variation in the seasonality and/or timescale of the facilitative mechanisms. The bidirectional and mechanistic design of our study revealed positive feedbacks that reinforced the traits conferring benefits to each partner, potentially stabilizing this positive interaction. Understanding how feedbacks influence the outcomes of facilitation is increasingly important as anthropogenic stressors increase globally.

Food‐borne polyphenols: A biocompatible anchor recuperating iron homeostasis

AbstractFood‐borne polyphenols have long contributed to human health via multifaceted mechanisms, while emerged studies especially those published in recent 10 years have witnessed the close relevance between the bioactivity of polyphenols with iron homeostasis. Polyphenols are involved in various physiological processes of iron and manifest with multidirectional regulative effects. The diversiform polyphenols–iron interactions have extended the cognition of various disorders and diseases. This review aims to present a comprehensive scope of polyphenols–iron interactions, and the structural property, biological effects, and molecular mechanism of polyphenols on iron homeostasis were systematically illustrated, categorized, exemplified, and discussed. Multiple related disorders and diseases were focused on, and the specific polyphenols–iron interactions were elucidated during the processes of pathogenesis, development, intervention, and treatment. Present shortages such as bidirectional effects, unclear mechanism, clinical challenges, and extraction efficiency of polyphenols were also analyzed, and some innovative techniques adopted for polyphenols–iron‐based systems or therapies explorations were discussed, inspiring future perspectives for the understandings, exploitations, and correlations of both iron homeostasis and polyphenols. This review brings the polyphenols–iron interactions on the stage, telling the full story of how polyphenols anchor iron to achieve beneficial bioactivities, enlightening ideas for polyphenols–iron interactions‐based understanding of diseases, and illumining strategies for polyphenols as dietary adjuvant or future therapeutic agents for iron‐related physiological abnormality.

Wave propagation, bi-directional reflectionless, and coherent perfect absorption-lasing in finite periodic PT-symmetric photonic systems

Abstract With consideration of parity-time (PT) symmetry, Lorentz reciprocity theorem, and real Bloch phase, we propose a generalized parametric space for any PT-symmetric unit cells that can comprehensively illustrate the PT phase transition, Bloch phase, and necessary conditions of exotic wave scattering in the general finite periodic PT photonic structures. We put forward rigorous and formal expressions of bi-directional reflectionless and coherent perfect absorption and lasing (CPAL) for the finite one-dimensional PT photonic structures. With a new concept of the parametric space, we demonstrate the necessary PT phases of general unit cells, which result in the abnormal bi-directional reflectionless and CPAL effects. Moreover, thanks to parametrization, analytical formulas for complex relative permittivities of the unit cells composed of subwavelength gain–loss heterostructure are derived to provide a guideline for manipulating different PT scattering events. We accordingly study several one-dimensional PT photonic systems to achieve exotic wave scattering enabled by PT-symmetry. We believe this work may offer a theoretical underpinning for studying extraordinary wave phenomena of PT-symmetric photonics and may open avenues for manipulation of light.

Is there evidence of a causal link between childhood maltreatment and attention deficit/hyperactivity disorder? Asystematic review of prospective longitudinal studies using the Bradford-Hill criteria.

Studies report an elevated risk of maltreatment in children with attention deficit/hyperactivity disorder (ADHD), and elevated levels of ADHD in people who suffered childhood maltreatment (CM). However, the direction(s) of causality between CM and ADHD remain unclear-does ADHD create a context for CM, does CM cause ADHD, or both? This study systematically reviews and qualitatively synthesizes the research evidence relating to this question using Bradford-Hill criteria for establishing causality-strength, temporality, dose-response and plausibility. We conducted a systematic review, following PRISMA guidelines, of prospective longitudinal studies examining both CM and ADHD. We then used Bradford-Hill criteria to assess the quality of evidence for a causal link between CM and ADHD. All 11 included studies demonstrated an association between CM and ADHD. Seven included evidence for temporality: five suggesting that CM precedes ADHD in the lifespan; two suggesting ADHD precedes CM. Four studies demonstrated a dose response relationship in which greater CM exposure was associated with elevated risk of ADHD. Studies presented a range of plausible mechanisms, including CM causing ADHD through biological programming, versus ADHD causing CM through parental stress. The high quality prospective longitudinal studies reviewed confirm the association between ADHD and CM, but present conflicting evidence about the direction of causality and mechanisms underpinning this association. To better understand the complex interplay between CM and ADHD, more studies using new research designs will be required that can partition effects by type of CM and account for bidirectional effects and other complexities.

Quiet Quitting: Building a Comprehensive Theoretical Framework

In this study, we aimed to introduce the recently popular concept of quiet quitting to the organizational behavior literature. Although we have met a handful of studies on the concept, we realized that the relevant studies do not address the concept comprehensively based on any theoretical background but only one. Therefore, we conducted this study, which is still in its infancy, for further researchers to conduct it empirically within the scope of cause-and-effect relationships in the organizational behavior literature. First, we grounded the term on Social Exchange Theory, Conservation of Resources Theory, and Theory of Generations. Second, we briefly defined the term. Third, we discussed possible antecedents, expected outcomes, issues having bi-directional effects, and the ways how to deal with these issues in organizations. Finally, we proposed a conceptual model including all possible cause-and-effect hypotheses.

Employee and customer perspectives in discovering the antecedent and output relationships for hotel branding development

PurposeThe purpose of this study is to propose and develop an antecedent model from star hotel employee viewpoint and a consequence model for star hotel customers’ evaluation of the brand equity development process.Design/methodology/approachIn terms of the study setting, structural equation modelling was conducted. Study 1 used the views of 323 star hotels’ employees on the mutual relationships among employee-based brand equity, and Study 2 used 516 star hotels’ customer perspectives concerning the mutual relationships among customer-based brand equity.FindingsIn the antecedent model of Study 1 from an employee viewpoint, service quality is a foundational attribute of the indirect influences of brand equity development through brand promise, values and message. A moderating role of brand identity is also found. In the consequence model of Study 2 from the perspective of customers’ evaluation, mutual relationships of brand equity are identified, and social interactions are established that enhance the positive relationships among the different critical attributes of brand equity.Originality/valueAlthough numerous hotel branding studies have identified the consequences of hotels for employees, few have simultaneously considered employees and customer feedback in terms of star hotel branding. This research considers the bidirectional effects of such a comprehensive perspective.

The road to integrate climate change projections with regional land‐use–biodiversity models

Abstract Current approaches to project spatial biodiversity responses to climate change mainly focus on the direct effects of climate on species while regarding land use and land cover as constant or prescribed by global land‐use scenarios. However, local land‐use decisions are often affected by climate change and biodiversity on top of socioeconomic and policy drivers. To realistically understand and predict climate impacts on biodiversity, it is, therefore, necessary to integrate both direct and indirect effects (via climate‐driven land‐use change) of climate change on biodiversity. In this perspective paper, we outline how biodiversity models could be better integrated with regional, climate‐driven land‐use models. We initially provide a short, non‐exhaustive review of empirical and modelling approaches to land‐use and land‐cover change (LU) and biodiversity (BD) change at regional scales, which forms the base for our perspective about improved integration of LU and BD models. We consider a diversity of approaches, with a special emphasis on mechanistic models. We also look at current levels of integration and at model properties, such as scales, inputs and outputs, to further identify integration challenges and opportunities. We find that LU integration in BD models is more frequent than the other way around and has been achieved at different levels: from overlapping predictions to simultaneously coupled simulations (i.e. bidirectional effects). Of the integrated LU‐BD socio‐ecological models, some studies included climate change effects on LU, but the relative contribution of direct vs. indirect effects of climate change on BD remains a key research challenge. Important research avenues include concerted efforts in harmonizing spatial and temporal resolution, disentangling direct and indirect effects of climate change on biodiversity, explicitly accounting for bidirectional feedbacks, and ultimately feeding socio‐ecological systems back into climate predictions. These avenues can be navigated by matching models, plugins for format and resolution conversion, and increasing the land‐use forecast horizon with adequate uncertainty. Recent developments of coupled models show that such integration is achievable and can lead to novel insights into climate–land use–biodiversity relations. Read the free Plain Language Summary for this article on the Journal blog.

The ecotoxicity of single-layer molybdenum disulfide nanosheets on freshwater microalgae Selenastrum capricornutum

Molybdenum disulfide (MoS2) nanomaterials have attracted considerable attention due to their unique physicochemical properties and promising applications, and subsequent risks to the environment and human health. However, the toxicological investigations of MoS2 nanosheets in aquatic environments are still limited. Herein, their aquatic toxic effects and involved mechanisms were explored using a freshwater green microalgae model, Selenastrum capricornutum. Several endpoints, including algal growth, photosynthetic pigment and macromolecular substances synthesis, were investigated after exposure to 0.02–50.0 mg/L MoS2 nanosheets. Furthermore, oxidative stress, membrane damage, lipid oxidation, and secretion of extracellular polymeric substances were elucidated as well. The results showed that single-layer MoS2 (SLMoS2) nanosheets at low concentrations (≤ 1.0 mg/L) stimulated the synthesis of chlorophyll and primary macromolecules, and they slightly promoted the growth of S. capricornutum. In contrast, higher concentrations of SLMoS2 (> 1.0 mg/L) inhibited algae growth through ROS-mediated membrane destruction and oxidative damage. Surprisingly, SLMoS2 accelerated extracellular polymeric substances (EPS) secretion and changed their fluorescent components, thus influencing algal growth. Taken together, MoS2 nanomaterials exerted bidirectional effects on S. capricornutum at the cellular, histological and organismal levels. These results provide considerable support regarding the adverse effects of MoS2 nanomaterials on freshwater microalgae.

Polystyrene microplastics trigger adiposity in mice by remodeling gut microbiota and boosting fatty acid synthesis

Microplastic (MP) pollution has become a global environmental problem, with particular concerns for its harmful effects on human health. Several studies have demonstrated that MP can penetrate animals and humans resulting in tissue dysfunction, but their influences on metabolism remain poorly understood. In this study, we investigated the impact of MP exposure on metabolism and the results showed that different treatment doses produce a bidirectional modulatory effects on mice. When exposed to high concentrations of MP, mice lost significant weight, while those in the lowest concentration treatment group showed little change, but those treated at relatively low concentrations became overweight. There was excessive lipid accumulation in these heavier mice, with a better appetite and lower activity level. Transcriptome sequencing revealed that MPs increased fatty acid synthesis in the liver. In addition, the gut microbiota composition of the MPs-induced obese mice was remodeled, which would enhance the nutrient absorption capacity of the intestine. Our results uncovered an MP dose-dependent lipid metabolism in mice and a non-unidirectional model of the physiological responses to different MP concentrations was proposed. These results provided new insights into the seemingly contradictory effects of MP on metabolism in the previous study.

Do Clean Energy and Financial Innovation Induce SME Performance? Clarifying the Nexus between Financial Innovation, Technological Innovation, Clean Energy, Environmental Degradation, and SMEs Performance in Bangladesh

The economic contribution of small and medium enterprises (SMEs) has been well appreciated and documented in the literature. On the other hand, another domain of studies has concentrated on discovering the key determinants of SMEs' growth and survival. The motivation of the study is to gauge the nexus between financial innovation, technological innovation, clean energy, environmental degradation, and SME performance in Bangladesh for the period 1991-2019. The study has implemented Autoregressive Distributed Lagged (ARDL), Nonlinear ARDL, and the Toda-Yamamoto causality test. Referring to output derived with ARDL, a study has exposed a positive and statistically significant link between explanatory variables, that is, financial innovation, technological innovation, and clean energy consumption and SMEs' contribution to GDP both in the long-run and short-run. At the same time, environmental degradation has been revealed to be adversely connected to SME performance. The results of the standard Wald test have established an asymmetric association between explained and explanatory variables in the long-run and short run. In terms of the directional causality test, the study disclosed bidirectional causal effects running between clean energy and SMEs performance [CEßàSME], foreign direct investment, and SMEs performance [FDIßàSME]. Based on the study findings, the policy suggestions have been introduced in light of future development in SMEs in Bangladesh.

Silver ion assisted urea complexation for the enrichment of sciadonic acid from Torreya fargesii kernel oil

Sciadonic acid (SA), a unique polymethylene-interrupted polyunsaturated fatty acids from Torreya grandi, drew increasing attention due to its multi healthy function. The one-step preparation for high purity SA by using urea crystallization method assisted by silver ion was investigated. Silver(I) tied the triunsaturated SA to stay in solution, while urea crystallization drawn the saturated and monounsaturated oleic acid into its channel to form complexes, these bidirectional enrichment effects increased the purity of SA to 89.3 % from initial 9.95 % with SA recovery of 32 %. The 1:1 silver ion/SA molar ratio produced the optimal purification performances. Raman spectra analysis of various molar ratio silver complex with SA supported this finding. Optimization on inclusion parameters suggested that urea concentration of 40 %, the mass ratio of fatty acid ethyl ester to urea is 1:4, cool rate at 0.5 °C /min were fit. In addition, the recycling of silver ion, urea and ethanol was performed over four cycles, and the results showed that the purity and recovery of SA among cycles were stable, and the purification performances were acceptable. Therefore, the developed silver ion assisted urea complexation strategy for the preparation of high purity SA is simple, economic, effective and has the potential for application on scale.

GPR-160 Receptor Signaling in the Dorsal Vagal Complex of Male Rats Modulates Meal Microstructure and CART-Mediated Hypophagia.

The g-protein coupled receptor GPR-160, recently identified as a putative receptor for the cocaine and amphetamine-regulated transcript (CART) peptide, shows abundant expression in the energy-balance control nuclei, including the dorsal vagal complex (DVC). However, its physiological role in the control of food intake has yet to be fully explored. Here, we performed a virally mediated, targeted knockdown (KD) of Gpr160 in the DVC of male rats to evaluate its physiological role in control of feeding. Our results indicate that DVC Gpr160 KD affects meal microstructure. Specifically, DVC Gpr160 KD animals consumed more frequent, but shorter meals during the dark phase and showed decreased caloric intake and duration of meals during the light phase. Cumulatively, however, these bidirectional effects on feeding resulted in no difference in body weight gain. We next tested the role of DVC GPR-160 in mediating the anorexigenic effects of exogenous CART. Our results show that DVC Gpr160 KD partially attenuates CART's anorexigenic effects. To further characterize Gpr160+ cells in the DVC, we utilized single-nucleus RNA sequencing data to uncover abundant GPR-160 expression in DVC microglia and only minimal expression in neurons. Altogether, our results suggest that DVC CART signaling may be mediated by Gpr160+ microglia, which in turn may be modulating DVC neuronal activity to control food intake.

Fractional-order PID control of tipping in network congestion

Tracing the rapid progress of communication network, the control of dynamic evolution of network has become a central issue. There are a lot of tipping phenomena in network congestion systems. Therefore, tipping control principally centres on traditional control policies, and some advanced control approaches need to be supplemented. In this paper, a fractional-order proportional-integral-derivative (PID) controller is introduced to a network congestion model to ponder corresponding bifurcation-induced tipping regulation. First, a fractional-order congestion model with fractional-order PID controller is constructed. Then the onset of the tipping induced by Hopf bifurcation of the uncontrolled model is studied. By contrast, the tipping point can be delayed under the controller for the controlled model. Some conditions under which Hopf bifurcation occurs are given. The stable and unstable ranges of control parameters for the controlled model are also deduced. At last, some simulated examples are given to verify the theoretical results and demonstrate the superiority of the controller in tipping regulation. Moreover, the bidirectional effects of the controller are displayed by manipulating the control parameters.