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Unveiling the roles personality plays during childhood and adolescence necessitates its accurate measurement, commonly using traditional Likert-type (LK) scales. However, this format is susceptible to various response biases, which can be particularly prevalent in children and adolescents, thus likely undermining measurement accuracy. Forced-choice (FC) scales appear to be a promising alternative because they are largely free from these biases by design. However, some argue that the FC format may not perform satisfactorily in children and adolescents due to its complexity. Little empirical evidence exists regarding the suitability of the FC format for children and adolescents. As such, the current study examined the psychometric performance of an FC measure of the Big Five personality factors in three children and adolescent samples: 5th to 6th graders (N = 428), 7th to 8th graders (N = 449), and 10th to 11th graders (N = 555). Across the three age groups, the FC scale demonstrated a better fit to the Big Five model and better discriminant validity in comparison to the LK counterpart. Personality scores from the FC scale also converged well with those from the LK scale and demonstrated high reliability as well as sizable criterion-related validity. Furthermore, the FC scale had more invariant statements than its LK counterpart across age groups. Overall, we found good evidence showing that FC measurement of personality is suitable for children and adolescents.
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The body-brain axis is emerging as a principal conductor of organismal physiology. It senses and controls organ function1,2, metabolism3 and nutritional state4-6. Here we show that a peripheral immune insult strongly activates the body-brain axis to regulate immune responses. We demonstrate that pro-inflammatory and anti-inflammatory cytokines communicate with distinct populations of vagal neurons to inform the brain of an emerging inflammatory response. In turn, the brain tightly modulates the course of the peripheral immune response. Genetic silencing of this body-brain circuit produced unregulated and out-of-control inflammatory responses. By contrast, activating, rather than silencing, this circuit affords neural control of immune responses. We used single-cell RNA sequencing, combined with functional imaging, to identify the circuit components of this neuroimmune axis, and showed that its selective manipulation can effectively suppress the pro-inflammatory response while enhancing an anti-inflammatory state. The brain-evoked transformation of the course of an immune response offers new possibilities in the modulation of a wide range of immune disorders, from autoimmune diseases to cytokine storm and shock.
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Encéphale , Cytokines , Inflammation , Neuro-immunomodulation , Animaux , Femelle , Mâle , Souris , Encéphale/cytologie , Encéphale/immunologie , Encéphale/métabolisme , Cytokines/immunologie , Cytokines/métabolisme , Inflammation/immunologie , Inflammation/métabolisme , Souris de lignée C57BL , Neuro-immunomodulation/immunologie , Neuro-immunomodulation/physiologie , Neurones/physiologie , Nerf vague/cytologie , Nerf vague/physiologie , Analyse de l'expression du gène de la cellule uniqueRÉSUMÉ
We advance the trait approach to leadership by leveraging a large multinational database on leader emergence (k = 120 samples, N = 32,579) and leader effectiveness (k = 116, N = 42,487) to extend Judge et al.'s (2002) classic meta-analysis of Big Five personality and leadership. By testing novel hypotheses rooted in culturally endorsed implicit leadership theory and socioanalytic theory, we offer three unique insights. First, in collectivist societies (cultures that value interdependence with one's group), the five factor model traits-and leader Extraversion and Agreeableness in particular-are stronger predictors of leader effectiveness, consistent with the theorized need for enhanced social coordination in such cultures. Second, a theoretical model is proposed to specify that leader Big Five trait effects are mediated by leader behavior (confirming that Consideration mediates Extraversion and Agreeableness, whereas Initiating Structure mediates Conscientiousness, Extraversion, and Openness). Third, trait Honesty-Humility robustly predicts leader effectiveness beyond the Big Five traits, expanding the trait approach. New implications for understanding when and why personality traits predict leadership are discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
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Objective: This study aimed to reveal associations between metabolic hormones in cerebral spinal fluid (CSF) and cigarette smoking-induced weight gain and to explore the underlying mechanism. Methods: A total of 156 adult men were included, comprising active smokers and nonsmokers. In addition to demographic information and body mass index (BMI), plasma levels of ApoA1 and ApoB, high-density lipoprotein, low-density lipoprotein, cholesterol, triglyceride, alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transferase in the participants were measured. Moreover, the metabolic hormones adiponectin, fibroblast growth factor 21 (FGF21), ghrelin, leptin, and orexin A, as well as the trace elements iron and zinc in CSF, were assessed. Results: Compared to nonsmokers, active smokers showed higher BMI, and elevated CSF levels of FGF21, Zn, and Fe, but decreased levels of metabolic hormones adiponectin, ghrelin, leptin, and orexin A. Negative correlations existed between CSF FGF21 and ghrelin, between CSF Zn and ghrelin, as well as between CSF Fe and orexin A in active smokers. Furthermore, elevated CSF FGF21 and Zn predicted ghrelin level decrease in the smokers. Conclusion: These data relate smoking-induced weight gain to its neurotoxic effect on the neurons that synthesize metabolic hormones such as adiponectin, ghrelin, leptin, or orexin A in the brain, by disrupting mitochondrial function and causing oxidative stress in the neurons.
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Biochar could promote humification in composting, nevertheless, its mechanism has not been fully explored from the perspective of the overall bacterial community and its metabolism. This study investigated the effects of bamboo charcoal (BC) and wheat straw biochar (WSB) on the humic acid (HA) and fulvic acid (FA) contents during pig manure composting. The results showed that BC enhanced humification more than WSB, and significantly increased the HA content and HA/FA ratio. The bacterial community structure under BC differed from those under the other treatments, and BC increased the abundance of bacteria associated with the transformation of organic matter compared with the other treatments. Furthermore, biochar enhanced the metabolism of carbohydrates and amino acids in the thermophilic and cooling phases, especially BC. Through Mantel tests and network analysis, we found that HA was mainly related to carbon source metabolism and the bacterial community, and BC might change the interaction patterns among carbohydrates, amino acid metabolism, Bacillales, Clostridiales, and Lactobacillales with HA and FA to improve the humification process during composting. These results are important for understanding the mechanisms associated with the effects of biochar on humification during composting.
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Charbon de bois , Compostage , Animaux , Suidae , Charbon de bois/composition chimique , Fumier/microbiologie , Sol/composition chimique , Substances humiques , Glucides , BactériesRÉSUMÉ
Understanding the sound power characteristics of parametric array loudspeakers (PALs) poses a unique challenge due to the nonlinear process involved. This work addresses this issue by employing the spherical convolution directivity model to obtain the far field intensity, which is then used to calculate the sound power radiated by a PAL. The results reveal that the audio sound power is approximately proportional to the square of the audio frequency and the aperture size, while inversely proportional to the ultrasound frequency. Additionally, the conversion efficiency from ultrasound to audio sound is found to be generally below 0.15% for typical configurations.
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OBJECTIVE: To summarise and critically appraise systematic review (SR) evidence on the effects of timing of complementary feeding (CF) on the occurrence of allergic sensitisation and disease. DESIGN: Overview of SRs. AMSTAR-2 and ROBIS were used to assess methodological quality and risk of bias (RoB) of SRs. RoB 2 Tool was used to assess RoB of primary randomised controlled trials (RCTs) (or extracted). The certainty of evidence (CoE) was assessed using GRADE. Findings were synthesised narratively. DATA SOURCES: MEDLINE (via PubMed and Ovid), the Cochrane Library and Web of Science Core Collection (2010 to 27 February 2023). ELIGIBILITY CRITERIA: SRs investigating the effects of timing of CF in infants or young children (0-3 years) on risk of developing food allergy (FA), allergic sensitisation, asthma, allergic rhinitis, atopic eczema and adverse events based on RCT evidence. RESULTS: Eleven SRs were included. Only two SRs had low RoB; common issues were failure to report on funding of primary studies and failure to provide a list of excluded trials. Common limitations of included trials were lack of blinding of outcome assessment or detailed trial preregistration, and inadequate handling of high loss to follow up. Primary study overlap was very high for specific FA and slight to moderate for FA in general and other primary outcomes. Introducing specific foods (peanut, cooked egg) early probably reduces the risk of specific FA. Evidence for other allergic outcomes was mostly very uncertain and based on few primary studies. Trials varied regarding timing of CF, nature of complementary foods and population risk, which limited comparability between SRs. CONCLUSIONS: For developing guidelines to support decision-making on the timing of CF as a preventive strategy, early introduction of specific foods (i.e. egg and peanut) seems promising and safe, whereas more extensive research is required regarding other allergic outcomes and potential adverse events.
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Asthme , Eczéma atopique , Hypersensibilité alimentaire , Nourrisson , Enfant , Enfant d'âge préscolaire , Humains , Revues systématiques comme sujet , Hypersensibilité alimentaire/prévention et contrôle , Phénomènes physiologiques nutritionnels chez le nourrissonRÉSUMÉ
Vision enables both image-forming perception, driven by a contrast-based pathway, and unconscious non-image-forming circadian photoentrainment, driven by an irradiance-based pathway1,2. Although two distinct photoreceptor populations are specialized for each visual task3-6, image-forming photoreceptors can additionally contribute to photoentrainment of the circadian clock in different species7-15. However, it is unknown how the image-forming photoreceptor pathway can functionally implement the segregation of irradiance signals required for circadian photoentrainment from contrast signals required for image perception. Here we report that the Drosophila R8 photoreceptor separates image-forming and irradiance signals by co-transmitting two neurotransmitters, histamine and acetylcholine. This segregation is further established postsynaptically by histamine-receptor-expressing unicolumnar retinotopic neurons and acetylcholine-receptor-expressing multicolumnar integration neurons. The acetylcholine transmission from R8 photoreceptors is sustained by an autocrine negative feedback of the cotransmitted histamine during the light phase of light-dark cycles. At the behavioural level, elimination of histamine and acetylcholine transmission impairs R8-driven motion detection and circadian photoentrainment, respectively. Thus, a single type of photoreceptor can achieve the dichotomy of visual perception and circadian photoentrainment as early as the first visual synapses, revealing a simple yet robust mechanism to segregate and translate distinct sensory features into different animal behaviours.
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Rythme circadien , Drosophila melanogaster , Cellules photoréceptrices d'invertébré , Perception visuelle , Animaux , Acétylcholine/métabolisme , Horloges biologiques/physiologie , Horloges biologiques/effets des radiations , Rythme circadien/physiologie , Rythme circadien/effets des radiations , Drosophila melanogaster/cytologie , Drosophila melanogaster/physiologie , Drosophila melanogaster/effets des radiations , Rétrocontrôle physiologique , Histamine/métabolisme , Agents neuromédiateurs/métabolisme , Cellules photoréceptrices d'invertébré/métabolisme , Cellules photoréceptrices d'invertébré/effets des radiations , Récepteurs cholinergiques/métabolisme , Récepteurs histaminergiques/métabolisme , Perception visuelle/physiologie , Perception visuelle/effets des radiationsRÉSUMÉ
Fungal degradation of cellulose is a key step in the conversion of organic matter in composting. This study investigated the effects of adding 10% biochar (including, prepared from corn stalk and rape stalk corresponding to CSB and RSB) on organic matter transformation in composting and determined the role of cellulase and fungal communities in the conversion of organic matter. The results showed that biochar could enhance the conversion of organic matter, especially in RSB treatment. Biochar could increase cellulase activity, and RSB could enhance 33.78% and 30.70% the average activity of cellulase compared with the control and CSB treatments in the mesophilic to thermophilic phase, respectively. The results of high throughput sequencing demonstrated that Basidiomycota dominant in mesophilic phase, and Ascomycota dominant in other phases of composting. The redundancy analysis showed that Alternaria, Thermomycees, Aspergillus, Wallemia, and Melanocarpus might be the key fungi for the degradation of organic matter, and Fusarium, Penicillium, and Scopulariopsis may promote the conversion of organic matter. Network showed that the addition of RSB changed the interactions between fungal communities and organic matter transformation, and RSB treatment enriched members of Ascomycota related to organic matter transformation and cellulase activity. These results indicated that RSB improved organic matter conversion by enhancing the role of cellulase and fungal communities.
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Cellulases , Compostage , Mycobiome , Animaux , Suidae , Sol , Fumier/microbiologie , Charbon de boisRÉSUMÉ
The bioavailability of phosphorus is a vital index for evaluating the quality of compost products. This study examined the effects of adding wheat straw biochar (WSB) and bamboo charcoal (BC) on the transformation of various phosphorus fractions during composting, as well as analyzing the roles of the phoD-harboring bacterial community in the transformation of phosphorus fractions. Adding WSB and BC reduced the available phosphorus content in the compost products by 35.2 % and 38.5 %, respectively. Redundancy analysis showed that the alkaline phosphatase content and pH were the most important factors that affected the transformation of phosphorus fractions. The addition of biochar resulted in changes in the composition and structures of the phoD-harboring bacteria communities during composting. In addition, the key bacterial genera that secreted alkaline phosphatase and decomposed different forms of phosphorus under WSB and BC were different compared with those under control. Network and correlation analysis demonstrated that the activities of phoD-harboring bacteria could have been enhanced by biochar to accelerate the consumption of available phosphorus, and the activities of key phosphorus-solubilizing bacteria (Lysobacter, Methylobacterium, and Saccharothrix) might be inhibited when the pH increased, thereby increasing the insoluble phosphorus content.
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Compostage , Suidae , Animaux , Fumier/microbiologie , Charbon de bois , Phosphore , Biodisponibilité , Phosphatase alcaline , Sol , Bactéries , TriticumRÉSUMÉ
Neuropsychological assessments are often surprisingly inaccurate in mapping clinically-reported attention-deficit hyperactivity disorder (ADHD) symptoms, presumably due to their low ecological validity. Virtual reality (VR) might offer a potential solution for this problem, given its capability to generate standardized and yet highly realistic virtual environments. As the first adaptation of existing virtual classroom scenarios to an adult population, we developed a Virtual Seminar Room (VSR) for multimodal characterization of ADHD symptoms. To test its feasibility, N = 35 healthy participants were immersed into the VSR via a head-mounted display and carried out a VR-embedded continuous performance task (CPT) under varying levels of distractions in two experimental blocks (24 min each). CPT performance, electroencephalography (EEG) measures, and head movements (actigraphy) were simultaneously recorded and analyzed offline. Although CPT performance remained constant throughout the task, head movements increased significantly from Block 1 to Block 2. In addition, EEG theta (4-7 Hz) and beta (13-30 Hz) power was higher during Block 1 than Block 2, and during distractor-present than distractor-absent phases. Moreover, P300 amplitudes were higher during Block 1 than Block 2, and P300 latencies were prolonged in distractor-absent compared with distractor-present phases. Although the paradigm awaits further improvements, this study confirms the general feasibility of the VSR and provides a first step toward a multimodal, ecologically valid, and reliable VR-based adult ADHD assessment.
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Trouble déficitaire de l'attention avec hyperactivité , Réalité de synthèse , Humains , Adulte , Trouble déficitaire de l'attention avec hyperactivité/diagnostic , Trouble déficitaire de l'attention avec hyperactivité/psychologie , Études de faisabilité , Volontaires sains , Tests neuropsychologiquesRÉSUMÉ
BACKGROUND: Virtual reality (VR) technologies are playing an increasingly important role in the diagnostics and treatment of mental disorders. OBJECTIVE: To systematically review the current evidence regarding the use of VR in the diagnostics and treatment of mental disorders. DATA SOURCE: Systematic literature searches via PubMed (last literature update: 9th of May 2022) were conducted for the following areas of psychopathology: Specific phobias, panic disorder and agoraphobia, social anxiety disorder, generalized anxiety disorder, posttraumatic stress disorder (PTSD), obsessive-compulsive disorder, eating disorders, dementia disorders, attention-deficit/hyperactivity disorder, depression, autism spectrum disorder, schizophrenia spectrum disorders, and addiction disorders. ELIGIBILITY CRITERIA: To be eligible, studies had to be published in English, to be peer-reviewed, to report original research data, to be VR-related, and to deal with one of the above-mentioned areas of psychopathology. STUDY EVALUATION: For each study included, various study characteristics (including interventions and conditions, comparators, major outcomes and study designs) were retrieved and a risk of bias score was calculated based on predefined study quality criteria. RESULTS: Across all areas of psychopathology, k = 9315 studies were inspected, of which k = 721 studies met the eligibility criteria. From these studies, 43.97% were considered assessment-related, 55.48% therapy-related, and 0.55% were mixed. The highest research activity was found for VR exposure therapy in anxiety disorders, PTSD and addiction disorders, where the most convincing evidence was found, as well as for cognitive trainings in dementia and social skill trainings in autism spectrum disorder. CONCLUSION: While VR exposure therapy will likely find its way successively into regular patient care, there are also many other promising approaches, but most are not yet mature enough for clinical application. REVIEW REGISTRATION: PROSPERO register CRD42020188436. FUNDING: The review was funded by budgets from the University of Bonn. No third party funding was involved.
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Trouble du spectre autistique , Démence , Troubles phobiques , Thérapie par réalité virtuelle , Réalité de synthèse , Humains , Trouble du spectre autistique/diagnostic , Trouble du spectre autistique/thérapie , Troubles phobiques/thérapie , Troubles anxieux/diagnostic , Troubles anxieux/thérapieRÉSUMÉ
The perception of fat evokes strong appetitive and consummatory responses1. Here we show that fat stimuli can induce behavioural attraction even in the absence of a functional taste system2,3. We demonstrate that fat acts after ingestion via the gut-brain axis to drive preference for fat. Using single-cell data, we identified the vagal neurons responding to intestinal delivery of fat, and showed that genetic silencing of this gut-to-brain circuit abolished the development of fat preference. Next, we compared the gut-to-brain pathways driving preference for fat versus sugar4, and uncovered two parallel systems, one functioning as a general sensor of essential nutrients, responding to intestinal stimulation with sugar, fat and amino acids, whereas the other is activated only by fat stimuli. Finally, we engineered mice lacking candidate receptors to detect the presence of intestinal fat, and validated their role as the mediators of gut-to-brain fat-evoked responses. Together, these findings reveal distinct cells and receptors that use the gut-brain axis as a fundamental conduit for the development of fat preference.
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Axe cerveau-intestin , Encéphale , Préférences alimentaires , Intestins , Neurones , Animaux , Souris , Acides aminés/métabolisme , Encéphale/cytologie , Encéphale/physiologie , Neurones/métabolisme , Sucres/métabolisme , Nerf vague/cytologie , Nerf vague/physiologie , Préférences alimentaires/physiologie , Analyse sur cellule unique , Axe cerveau-intestin/génétique , Axe cerveau-intestin/physiologie , Intestins/innervation , Intestins/métabolismeRÉSUMÉ
The master circadian clock generates 24-hour rhythms to orchestrate daily behavior, even running freely under constant conditions. Traditionally, the master clock is considered self-sufficient in sustaining free-running timekeeping via its cell-autonomous molecular clocks and interneuronal communications within the circadian neural network. Here, we find a set of bona fide ultradian oscillators in the Drosophila brain that support free-running timekeeping, despite being located outside the master clock circuit and lacking clock gene expression. These extra-clock electrical oscillators (xCEOs) generate cell-autonomous ultradian bursts, pacing widespread burst firing and promoting rhythmic resting membrane potentials in clock neurons via parallel monosynaptic connections. Silencing xCEOs disrupts daily electrical rhythms in clock neurons and impairs cycling of neuropeptide pigment dispersing factor, leading to the loss of free-running locomotor rhythms. Together, we conclude that the master clock is not self-sufficient to sustain free-running behavior rhythms but requires additional endogenous inputs to the clock from the extra-clock ultradian brain oscillators.
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The effects of different yeast strains including Pichia kudriavzevii, Torulaspora delbrueckii, and Debaryomyces hansenii on the taste and odour profiles of reduced-salt dry sausages were explored. Inoculation of P. kudriavzevii and D. hansenii compensated for the lack of saltiness and umami tastes of reduced-salt sausages. Furthermore, inoculation of P. kudriavzevii and T. delbrueckii resulted in an odour profile in the reduced-salt dry sausages that was similar to traditional dry sausages. According to the volatile analysis, the contents of certain alcohols, acids, esters and terpenes were higher in the inoculated sausages. Finally, the sensory evaluation indicated that the inoculation of P. kudriavzevii and D. hansenii contributed positively to the aroma and saltiness of reduced-salt dry sausages. In conclusion, P. kudriavzevii and D. hansenii can be employed as effective starter cultures to compensate for the flavour deficiencies of reduced-salt dry sausages.
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Recently, there has been increasing interest in adopting the forced-choice (FC) test format in non-cognitive assessments, as it demonstrates faking resistance when well-designed. However, traditional or manual pairing approaches to FC test construction are time- and effort- intensive and often involve insufficient considerations. To address these issues, we developed the new open-source autoFC R package to facilitate automated and optimized item pairing strategies. The autoFC package is intended as a practical tool for FC test constructions. Users can easily obtain automatically optimized FC tests by simply inputting the item characteristics of interest. Customizations are also available for considerations on matching rules and the behaviors of the optimization process. The autoFC package should be of interest to researchers and practitioners constructing FC scales with potentially many metrics to match on and/or many items to pair, essentially exempting users from the burden of manual item pairing and reducing the computational costs and biases induced by simple ranking methods.
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Although prior studies have demonstrated the associations between parental socialization goals and parenting practices, as well as parenting practices and adolescent depressive symptoms, respectively, research examining the comprehensive developmental pathways among these constructs (i. e., the path from parental socialization goals to parenting practices to adolescent depressive symptoms) is scarce, especially in the Chinese context. Grounded in the integrative model of parenting, this study investigated the associations between parental socialization goals and adolescent depressive symptoms by examining the indirect pathways through parents' autonomy support and psychological control as well as the moderating effect of educational stage. In Study 1, 345 Chinese adolescents and their primary caregivers completed a measure on parental socialization goals. Adolescents also reported on their depressive symptoms. Results showed that children who reported more self-development parental goals showed fewer depressive symptoms. However, parents' reports of goals or child-parent perceptual discrepancies were not related to children's depressive symptoms. Drawing on this finding, 424 middle school and 301 high school Chinese adolescents completed measures regarding parental socialization goals, autonomy support, psychological control, and their own depressive symptoms in Study 2. Results showed that parental autonomy support linked the associations of self-development and achievement-oriented parental goals and children's depressive symptoms among middle school students, whereas parental psychological control linked such associations among high school students. Our findings provide a more holistic view on how parents' socialization goals are related to children's depressive symptoms via their parenting practices. We also discussed the practical implications for the clinical work regarding adolescent depressive symptoms.
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Biochar possesses a unique porous structure and abundant surface functional groups, which can potentially help mitigate greenhouse gas (GHG) emissions from compost. This review summarizes the properties and functions of biochar, and the effects of biochar on common GHGs (methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O)) and ammonia (NH3, an indirect GHG) during composting. Studies have shown that it is possible to improve the mitigation of GHG emissions during composting by adjusting the biochar amount, type of raw material, pyrolysis temperature, and particle size. Biochar produced from crop residues and woody biomass has a greater effect on mitigating CH4, N2O, and NH3 emissions during composting, and GHG emissions can be reduced significantly by adding about 10% (w/w) biochar. Biochar produced by high temperature pyrolysis (500-900 °C) has a greater effect on mitigating CH4 and N2O emissions, whereas biochar generated by low temperature pyrolysis (200-500 °C) is more effective at reducing NH3 emissions. Interestingly, adding granular biochar is more beneficial for mitigating CH4 emissions, whereas adding powdered biochar is better at reducing NH3 emissions. According to the current research status, developing new methods for producing and using biochar (e.g., modified or combined with other additives) should be the focus of future research into mitigating GHG emissions during composting. The findings summarized in this review may provide a reference to allow the establishment of standards for using biochar to mitigate GHG emissions from compost.
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Compostage , Gaz à effet de serre , Dioxyde de carbone/analyse , Charbon de bois , Gaz à effet de serre/analyse , Méthane/analyse , Protoxyde d'azote/analyse , SolRÉSUMÉ
Ferredoxin reductase (FDXR), a mitochondrial membrane-associated flavoprotein, is essential for electron transfer and modulates p53-dependent apoptosis in cancer cells.FDXR may be implicated in epidermal and sebocytic differentiation, but its explicit function in sebocytes remains to be elucidated. In the present study, immunohistochemistry revealed that FDXR expression was increased in sebaceous cells of acne lesions. FDXR, PPARγ, LXRα/ß, SREBP1 and Sox9 expression was incremental during sebocyte differentiation. FDXR overexpression induced by Ad-GFP-FDXR infection enhanced differentiation, reactive oxygen species (ROS), lipogenesis and PPARγ expression, and consequnently inhibited proliferation in SZ95 sebocytes. Flow cytometry showed that FDXR overexpression induced significant blockade of G2/M phase but had no effect on sub-G1 (apoptotic) sebocytes. Insulin-like growth factor-1 (IGF-1)-induced FDXR and PPARγ expression and lipogenesis were abolished by pretreatment with PI3K inhibitor LY294002. These results suggest that FDXR overexpression might promote differentiation and lipogenesis via ROS production and suppress proliferation via G2/S blockade in SZ95 sebocytes. IGF-1 could facilitate differentiation and lipogenesis through PI3K/Akt/FDXR pathway. FDXR could serve as a potential marker of advanced sebaceous differentiation, and its overexpression may be involved in the development of acne lesions.
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Apoptose/effets des médicaments et des substances chimiques , Cycle cellulaire/effets des médicaments et des substances chimiques , Différenciation cellulaire/effets des médicaments et des substances chimiques , Ferrédoxines/pharmacologie , Lipogenèse/effets des médicaments et des substances chimiques , Respiration cellulaire/effets des médicaments et des substances chimiques , Cellules épithéliales/effets des médicaments et des substances chimiques , HumainsRÉSUMÉ
BACKGROUND: Pulmonary infections caused by non-diphtheriae corynebacteria are increasing. However, rapid identification of Corynebacterium species poses a challenge due to the low genetic variation within the genus. METHODS: Three reference strains and 99 clinical isolates were used in this study. A qPCR followed by high-resolution melting (HRM) targeting ssrA was performed to simultaneously identify C. striatum, C. propinquum and C. simulans. To further evaluate this assay's performance, 88 clinical sputum samples were tested by HRM and the detection results were compared with those of the traditional culture method and multiple cross-displacement amplification (MCDA) assay. RESULTS: The melting curve produced by a pair of universal primers generated species-specific HRM curve profiles and could distinguish the three target species from other related bacteria. The limit of detection of HRM assay for DNA from the three purified Corynebacterium species was 100 fg. Compared with the culture method, HRM detected 22 additional positive specimens, representing a 23.9% relative increase in detection rate. The HRM assay had 98.4% (95% confidence interval [CI], 90.5-99.9%) sensitivity and 100% (95% CI, 82.8-100%) specificity. Additionally, 95.5% concordance between HRM and MCDA (κ = 0.89 [95% CI, 0.79-0.99]) was noted. CONCLUSIONS: The HRM assay was a simple, rapid, sensitive, and specific diagnostic tool for detecting C. striatum, C. propinquum, and C. simulans, with the potential to contribute to early diagnosis, epidemiological surveillance, and rapid response to outbreak.