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1.
Rev Neurosci ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38738975

RESUMEN

Overweight (OW) and obesity (OB) have become prevalent issues in the global public health arena. Serving as a prominent risk factor for various chronic diseases, overweight/obesity not only poses serious threats to people's physical and mental health but also imposes significant medical and economic burdens on society as a whole. In recent years, there has been a growing focus on basic scientific research dedicated to seeking the neural evidence underlying overweight/obesity, aiming to elucidate its causes and effects by revealing functional alterations in brain networks. Among them, dysfunction in the reward network (RN) and executive control network (ECN) during both resting state and task conditions is considered pivotal in neuroscience research on overweight/obesity. Their aberrations contribute to explaining why persons with overweight/obesity exhibit heightened sensitivity to food rewards and eating disinhibition. This review centers on the reward and executive control network by analyzing and organizing the resting-state and task-based fMRI studies of functional brain network alterations in overweight/obesity. Building upon this foundation, the authors further summarize a reward-inhibition dual-system model, with a view to establishing a theoretical framework for future exploration in this field.

2.
Brain Sci ; 14(3)2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38539610

RESUMEN

BACKGROUND: Unhealthy food compensation following exercise contributes to the failure of exercise for weight loss. Autonomous exercise motivation is a protective factor against exercise-induced unhealthy foods licensing (EUFL). However, the neural mechanism of exercise-specific autonomous motivation and how these neural correlates link to EUFL remain uncertain. METHODS: This study explored the resting-state brain activity (i.e., amplitude or fractional amplitude of low-frequency fluctuations (ALFF/fALFF) and regional homogeneity (ReHo)) and seed-based functional connectivity (rsFC) of autonomous exercise motivation among 223 (72.3% female) healthy young adults. Autonomous exercise motivation and EUFL were measured by self-report measurements. RESULTS: Results across resting-state indices and rsFC analysis show that autonomous exercise motivation was robustly associated with activity and connectivity within the cerebellum posterior lobe (PCB), middle frontal gyrus (MFG), and middle occipital gyrus (MOG). Specifically, the PCB acted as a hub, connecting the frontal and occipital lobes. Moreover, higher autonomous exercise motivation indirectly predicts reduced EUFL through enhanced activity in the MFG and connectivity of PCB-MOG. CONCLUSIONS: Neural substrate for enhanced conflict awareness and motor control may explain the protective effect of autonomous exercise motivation on post-exercise unhealthy eating. Enhancement of these functions could help regulate post-exercise eating and improve the effectiveness of exercise for weight loss.

3.
J Am Chem Soc ; 146(11): 7605-7615, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38467427

RESUMEN

Cu-SSZ-13 has been commercialized for selective catalytic reduction with ammonia (NH3-SCR) to remove NOx from diesel exhaust. As its synthesis usually requires toxic and costly organic templates, the discovery of alternative Cu-based zeolite catalysts with organotemplate-free synthesis and comparable or even superior NH3-SCR activity to that of Cu-SSZ-13 is of great academic and industrial significance. Herein, we demonstrated that Cu-T with an intergrowth structure of offretite (OFF) and erionite (ERI) synthesized by an organotemplate-free method showed better catalytic performance than Cu-ERI and Cu-OFF as well as Cu-SSZ-13. Structure characterizations and density functional theory calculations indicated that the intergrowth structure promoted more isolated Cu2+ located at the 6MR of the intergrowth interface, resulting in a better hydrothermal stability of Cu-T than Cu-ERI and Cu-OFF. Strikingly, the low-temperature activity of Cu-T significantly increased after hydrothermal aging, while that of Cu-ERI and Cu-OFF substantially decreased. Based on in situ diffuse reflectance infrared Fourier transform spectra analysis and density functional theory calculations, the reason can be attributed to the fact that NH4NO3 formed on the CuxOy species within ERI polymorph of Cu-T underwent a fast SCR reaction pathway with the assistance of Brønsted acid sites at the intergrowth interfaces under standard SCR reaction conditions. Significantly, Cu-T exhibited a wider temperature window at a catalytic activity of over 90% than Cu-SSZ-13 (175-550 vs 175-500 °C for fresh and 225-500 vs 250-400 °C for hydrothermal treatment). This work provides a new direction for the design of high-performance NH3-SCR catalysts in terms of the interplay of the intergrowth structure of zeolites.

4.
Child Neuropsychol ; : 1-18, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38375872

RESUMEN

Preserving a normal body mass index (BMI) is crucial for the healthy growth and development of children. As a core aspect of executive functions, inhibitory control plays a pivotal role in maintaining a normal BMI, which is key to preventing issues of childhood obesity. By studying individual variations in inhibitory control performance and its associated connectivity-based neuromarker in a sample of primary school students (N = 64; 9-12 yr), we aimed to unravel the pathway through which inhibitory control impacts children's BMI. Utilizing resting-state functional MRI scans and a connectivity-based psychometric prediction framework, we found that enhanced inhibitory control abilities were primarily associated with increased functional connectivity in brain structures vital to executive functions, such as the superior frontal lobule, superior parietal lobule, and posterior cingulate cortex. Conversely, inhibitory control abilities displayed a negative relationship with functional connectivity originating from reward-related brain structures, such as the orbital frontal and ventral medial prefrontal lobes. Furthermore, we revealed that both inhibitory control and its corresponding neuromarker can moderate the association between food-related delayed gratification and BMI in children. However, only the neuromarker of inhibitory control maintained its moderating effect on children's future BMI, as determined in the follow-up after one year. Overall, our findings shed light on the potential mechanisms of how inhibitory control in children impacts BMI, highlighting the utility of the connectivity-based neuromarker of inhibitory control in the context of childhood obesity.

5.
Obesity (Silver Spring) ; 32(2): 291-303, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38269472

RESUMEN

OBJECTIVE: Overweight and obesity, as commonly indicated by a higher BMI, are associated with functional alterations in the brain, which may potentially result in cognitive decline and emotional illness. However, the manner in which these detrimental impacts manifest in the brain's dynamic characteristics remains largely unknown. METHODS: Based on two independent resting-state functional magnetic resonance imaging data sets (Behavioral-Brain Research Project of Chinese Personality, n = 1923; Human Connectome Project, n = 998), the current study employed a Hidden Markov model to identify the spatiotemporal features of brain activity states. Subsequently, the study examined the changes in brain-state dynamics and the corresponding functional outcomes that arise with an increase in BMI. RESULTS: Elevated BMI tends to shift the brain's activity states toward a greater emphasis on a specific set of states, i.e., the metastate, that are relevant to the joint activities of sensorimotor systems, making it harder to transfer to the metastate of transmodal systems. These findings were reconfirmed in a longitudinal sample (Behavioral-Brain Research Project of Chinese Personality, n = 34) that exhibited a significant increase in BMI at follow-up. Importantly, the alternation of brain-state dynamics specifically mediated the relationships between BMI and adverse functional outcomes, including cognitive decline and symptoms of mental illness. CONCLUSIONS: The altered brain-state dynamics within the sensorimotor-to-transmodal hierarchy provide new insights into obesity-related brain dysfunctions and mental health issues.


Asunto(s)
Encéfalo , Emociones , Humanos , Índice de Masa Corporal , Encéfalo/diagnóstico por imagen , Obesidad
6.
Environ Sci Technol ; 57(48): 19956-19964, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-37948508

RESUMEN

Pd/SSZ-13 has been proposed as a passive NOx adsorber (PNA) for low-temperature NOx adsorption. However, it remains challenging for Pd/SSZ-13 to work efficiently when suffering from phosphorus poisoning. Herein, we report a simple and efficient strategy to regenerate the phosphorus-poisoned Pd/SSZ-13 based on the cooperation between hydrothermal aging treatment and Na cocations. It was found that hydrothermal aging treatment enabled the redispersion of Pd and P-containing species in phosphorus-poisoned Pd/SSZ-13. Meanwhile, the presence of Na cocations significantly reduced the formation of AlPO4 and retained more paired Al sites for highly dispersed Pd2+ ions, which was of great importance for the recovery of adsorption performance. To our satisfaction, the restoration ratio of the adsorption capacity of poisoned Pd/SSZ-13 was >90% after regeneration. Strikingly, the NOx adsorption activities of phosphorus-poisoned Pd/SSZ-13 with phosphorus loadings of 0.2 and 0.4 mmol g-1 almost completely recovered upon regeneration. This study demonstrates the promoting effect of Na cocations on the regeneration of phosphorus-poisoned Pd/SSZ-13 by hydrothermal aging treatment, which provides useful guidance for the design of PNA materials with excellent durability for cold-start application.


Asunto(s)
Fósforo , Venenos , Adsorción , Iones
8.
Front Neurosci ; 17: 1182728, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37397442

RESUMEN

Introduction: Chronic stress is a long-term condition that negatively affects cognitive ability and mental health. Individuals who experience chronic stress show poor attentional control. Transcranial direct current stimulation (tDCS) to the dorsolateral prefrontal cortex (DLPFC) modulates executive function domains. Therefore, it is beneficial to investigate whether tDCS of the DLPFC could improve attentional control and relieve stress in chronically stressed individuals. Methods: We assess the event-related potentials (ERPs) associated with attentional control in individuals with chronic stress after the tDCS intervention. Forty individuals were randomly assigned to either the anodal tDCS group, which received 5 sessions of the 20 min tDCS over the DLPFC (2 mA; n = 20), or the sham tDCS (n = 20). Participants' stress levels, anxiety, depressive symptoms, and state affects were assessed and compared before and after the intervention. The ERP was collected through electroencephalography (EEG) technology during an attentional network test. Results: After the anodal tDCS, we found a significant decrease in the perceived stress scale (PSS) scores (from an average score of 35.05 to 27.75), p = 0.01 as well as the State-Trait Anxiety Inventory (STAI) scores, p = 0.002. Better performance in the attentional network test, a significant reduction in the N2 amplitudes, and an enhancement in the P3 amplitudes (both cues and targets) were also found in the anodal tDCS group. Discussion: Our study findings suggest that tDCS to the left DLPFC could effectively relieve chronic stress, potentially reflected by increased attentional control.

9.
Angew Chem Int Ed Engl ; 62(32): e202306174, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37190928

RESUMEN

Cu-exchanged low-silica CHA zeolites (Si/Al≤4) synthesized without organic templates are promising candidate catalysts for ammonia selective catalytic reduction of nitrogen oxides (NH3 -SCR), but their practical application is restricted due to the low hydrothermal stability. Here, inspired by the transcription from duplex DNA to RNA, we synthesized Al pairs enriched low-silica CHA zeolite (CHA-SPAEI, Si/Al=3.7) by using silicoaluminophosphate (SAPO) featured by strict alternation of -Al-O-P(Si)-O-Al-O- tetrahedra as seed. The proportion of Al pairs in CHA-SPAEI is 78 %, which is much higher than that in the conventional low-silica CHA (CHA-LS, 52 %). After hydrothermal ageing at 800 °C for 6 h, Cu-exchanged CHA-SPAEI shows NO conversion above 90 % within 225-500 °C under a gas hourly space velocity of 200,000 h-1 , which is much better than that of Cu-exchanged CHA-LS. The spatial close proximity of Al pairs in CHA-SPAEI is confirmed by the 27 Al double-quantum single-quantum two-dimensional NMR analyses. The strict -P(Si)-O-Al-O-P(Si)-O- sequence in the fragments from the dissolution of SAPO seed promotes the Al pairs with the -Al-O-Si-O-Al-O- sequence via a transcription process. The utilization of aluminophosphate-based zeolites as seeds opens up a new avenue for the regulation of the Al distribution in zeolites.

10.
Adv Mater ; : e2302912, 2023 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-37177904

RESUMEN

Core-shell catalysts with functional shells can increase the activity and stability of the catalysts in selective catalytic reduction of NOx with ammoniax . However, the conventional approaches based on multistep fabrication for core-shell structures encounter persistent restrictions regarding strict synthesis conditions and limited design flexibility. Herein, a facile coaxial 3D printing strategy is for the first time developed to construct zeolite-based core-shell monolithic catalysts with interconnected honeycomb structures, in which the hydrophilic noncompact silica serves as shell and Cu-SSZ-13 zeolite acts as core. Compared to a Cu-SSZ-13 monolith which suffers from the interfacial diffusion, the SiO2 shell layer can increase the accessibility of active sites over Cu-SSZ-13@SiO2 , resulting in a 10-20% higher NO conversion at200-550 °C under 300 000 cm3 g-1 h-1 . Meanwhile, a thicker SiO2 shell enhances the hydrothermal stability of the aged catalyst by inhibiting the dealumination and the formation of CuOx . Other representative monolithic catalysts with different topological zeolites as shell and diverse metal oxides as the core can be also realized by this coaxial 3D printing. This strategy allows multiple porous materials to be directly integrated, which allows for flexible design and fabrication of various core-shell monolithic catalysts with customized functionalities.

11.
Angew Chem Int Ed Engl ; 62(23): e202219313, 2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37021740

RESUMEN

N-Type thermoelectrics typically consist of small molecule dopant+polymer host. Only a few polymer dopant+polymer host systems have been reported, and these have lower thermoelectric parameters. N-type polymers with high crystallinity and order are generally used for high-conductivity ( σ ${\sigma }$ ) organic conductors. Few n-type polymers with only short-range lamellar stacking for high-conductivity materials have been reported. Here, we describe an n-type short-range lamellar-stacked all-polymer thermoelectric system with highest σ ${\sigma }$ of 78 S-1 , power factor (PF) of 163 µW m-1 K-2 , and maximum Figure of merit (ZT) of 0.53 at room temperature with a dopant/host ratio of 75 wt%. The minor effect of polymer dopant on the molecular arrangement of conjugated polymer PDPIN at high ratios, high doping capability, high Seebeck coefficient (S) absolute values relative to σ ${\sigma }$ , and atypical decreased thermal conductivity ( κ ${\kappa }$ ) with increased doping ratio contribute to the promising performance.

12.
Neuroscience ; 517: 1-17, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36764599

RESUMEN

This study aimed to explore the neural mechanisms underlying food decision making in unsuccessful restrained eaters (US-REs) and successful restrained eaters (S-REs). During a functional magnetic resonance imaging scan, participants were required to choose between pairs of high- and low-calorie foods under the following conditions: the congruent condition (choose between high- and low-calorie foods with the same level of tastiness) and incongruent condition (choose between high-calorie foods tastier than the corresponding low-calorie foods). Subsequently, the participants' diets were monitored for one week. The behavioral results showed that US-REs (n = 28) chose more high-calorie foods than S-REs (n = 26); in contrast, S-REs spent more time in choosing for the incongruent than the congruent condition. The fMRI results found that US-REs exhibited more activity in reward regions (caudate and thalamus) than S-REs in the congruent condition. In the incongruent condition, S-REs showed stronger functional connectivity between the conflict-monitoring region (anterior cingulate cortex) and inhibitory-control regions (inferior frontal gyrus [IFG] and medial frontal gyrus) than US-REs. In both the conditions, increased activation of the insula, putamen, middle frontal gyrus, and IFG could predict increased food intake among US-REs in the following week. Furthermore, in both the conditions, increased IFG activation could predict decreased food cravings among S-REs during the following week. Our results suggest that US-REs have a strong reward response to food. Compared to US-REs, S-REs are more guided more by the goal of weight control, and exhibit strong functional connections between the conflict-monitoring and inhibitory-control regions. Therefore, eating enjoyment and weight-control goals influence restrained eating in daily life.


Asunto(s)
Conducta Alimentaria , Alimentos , Humanos , Conducta Alimentaria/fisiología , Motivación , Ansia , Dieta , Imagen por Resonancia Magnética , Ingestión de Alimentos
13.
ChemSusChem ; 16(6): e202201936, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36545829

RESUMEN

The valorization of non-grain biomass feedstocks to value-added chemicals, polymers and alternative fuels is a crucial route for the utilization of renewable resources. Inulin belongs to a type of fructans, which is a pivotal platform bridging upstream fructose-rich biomass feedstocks typically represented by Jerusalem artichoke and downstream platform molecules such as alcohols, aldehydes and acids. Fructose can be directly obtained from the inulin hydrolysis and further converted into various platform chemicals, which is a more environmentally economical route than the conventional catalytic upgrading of cellulose. Nevertheless, most perspectives over the last decade have focused on the valorization of cellulose-derived carbohydrates, without much emphasis on the practical importance of one-pot transformation of inulin. In this review, we aim to demonstrate an efficient one-pot tandem transformation system of the inulin as fructose-rich platform towards 5-hydroxymethylfurfural (HMF). Core concerns are placed on elucidating the contributing roles of acid sites and solvents in enhancing the overall catalytic performance. The perspectives presented in this review may contribute to the innovation in the catalytic refining of fructose-rich non-grain biomass and the development of a greener biomass-based energy system.

14.
Oxid Med Cell Longev ; 2022: 6659183, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36267816

RESUMEN

Sepsis remains a complicated and incompletely understood syndrome, and myocardial dysfunction is one of the main complications contributing to poor clinical outcomes. Accumulating evidence has revealed the critical involvement of the deregulated expression of specific microRNAs (miRNAs) in cardiac pathologies caused by sepsis. Intriguingly, miR-377 has been correlated with cardiomyocyte apoptosis, whereas its effect on myocardial hypertrophy remains to be illustrated. Thus, the current study sets out to explore the impact and underlying mechanism of miR-377 on myocardial hypertrophy induced by sepsis. The expression pattern of miR-377 was detected in myocardial tissues of septic mice induced by cecal ligation-perforation (CLP). We found that miR-377 was highly expressed in myocardial tissues of CLP-induced septic mice with cardiomyocyte hypertrophy. Besides, miR-377 inhibition could relieve cardiomyocyte hypertrophy and reduce inflammation in septic mice. Further, mechanistic studies found that miR-377 could target Rcan2 and then regulate calcineurin (CaN) activity via Ca2+/CaN signaling pathway. Collectively, our findings illuminate that miR-377 enhances myocardial hypertrophy caused by sepsis, by targeting Rcan2 and further regulating the Ca2+/CaN signaling pathway. This work highlights downregulation of miR-377 as a novel target for the management of sepsis-induced myocardial hypertrophy.


Asunto(s)
Calcineurina , Cardiomegalia , Péptidos y Proteínas de Señalización Intracelular , MicroARNs , Sepsis , Animales , Ratones , Calcineurina/metabolismo , Cardiomegalia/metabolismo , Cardiomegalia/patología , MicroARNs/genética , Miocardio/patología , Sepsis/complicaciones , Sepsis/genética , Péptidos y Proteínas de Señalización Intracelular/metabolismo
15.
Acc Chem Res ; 55(18): 2604-2615, 2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-36074952

RESUMEN

Photon upconversion, the process of converting low-energy photons into high-energy ones, has been widely applied for solar energy conversion, photoredox catalysis, and various biological applications such as background-free bioimaging, cancer therapy, and optogenetics. Upconversion materials that are based on triplet-triplet annihilation (TTA) are of particular interest due to their low excitation power requirements (e.g., ambient sunlight) and easily tunable excitation and emission wavelengths. Despite advances that have been made with respect to TTA upconversion (TTA-UC) in the past decade, several challenges remain for near-infrared light-activatable triplet-triplet annihilation upconversion (NIR TTA-UC). These challenges include low upconversion quantum yield, small anti-Stokes shift, and incompatibility with oxygen, the latter of which seriously limits the practical applications of NIR TTA-UC.This Account will summarize the recent research endeavors to address the above-mentioned challenges and the recent new applications. The first part of this Account highlights recent strategies of molecular design to modulate the excited states of photosensitizers and annihilators, two key factors to determine TTA-UC performance. Novel molecular engineering strategies such as the resonance energy transfer method, dimerization of dye units, and the helix twist molecular structure have been proposed to tune the excited states of photosensitizers. The obtained photosensitizers exhibited enhanced absorption of deep tissue penetrable near-infrared (NIR) light, produced a triplet excited state with elevated energy level and prolonged lifetime, and promoted intersystem crossing, leading to an upgraded TTA-UC system with significantly expanded anti-Stokes shift. With respect to the annihilator, the perylene derivatives were systematically explored, and their attached aromatic groups were found to be the key to adjusting the energy levels of both the triplet and singlet excited states. The resultant optimal TTA-UC system exhibits the highest recorded efficiency among NIR TTA-UC systems.Moreover, to resolve the oxygen-induced TTA-UC quenching, enzymatic reactions were recently introduced. More specifically, the glucose oxidase-catalyzed glucose oxidation reaction showed the ability to rapidly consume oxygen to turn on the TTA-UC luminescence in an aqueous solution. The resultant TTA-UC nanoparticle was able to detect glucose and an enzyme related to glucose metabolism in a highly specific, sensitive, and background-free manner. Further, the upconverted singlet excited state of the annihilator was directly utilized as the catalyst or the excited substrate. For example, the modification of annihilators and drug molecules with photolabile linkages can realize the long wavelength light-induced photolysis. Compared to direct short-wavelength-driven photolysis, this sensitized TTA photolysis (TTAP) exhibits superior reaction yield and lower photodamage, which are important in the release of drugs for tumor treatment in vivo. Moreover, the improved upconversion efficiency can enable the successful coupling of NIR TTA-UC with a visible light absorbing photocatalyst for NIR-driven photoredox catalysis. Compared to direct visible-light photocatalysis, TTA-UC mediated NIR photoredox catalysis showed superior product yield especially in large scale reaction systems owing to the deep penetration power of NIR light. More interestingly, among a few promising technology applications, three-dimensional (3D) printing based on photopolymerization can operate with faster speed and energy-input several orders of magnitude lower when the two-photon polymerization is replaced with TTA-UC mediated polymerization. We believe this Account will spur interest in the further development and application of TTA-UC in the areas of energy, chemistry, material science, and biology.


Asunto(s)
Perileno , Fármacos Fotosensibilizantes , Glucosa , Glucosa Oxidasa , Rayos Infrarrojos , Oxígeno/química , Fármacos Fotosensibilizantes/química
16.
Appetite ; 179: 106309, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36115512

RESUMEN

OBJECTIVES: This study aims to reveal the individual differences in Neuroticism and cognitive flexibility among successful restrained eaters (SREs), unsuccessful restrained eaters (UREs), and non-restrained eaters (NREs). Moreover, this study is dedicated to investigating whether certain personality traits and cognitive flexibility could concurrently influence disinhibited eating behaviors among restrained eaters and reveal the pathways through which they interact. METHODS: Female participants aged 17 and 24 years (NREs = 23; SREs = 24; UREs = 23) were assessed with body mass index (BMI) and appetite state measurement, the Dutch Eating Behavior Questionnaire (DEBQ), the NEO Five-Factor Inventory (NEO-FFI), and the Positive and Negative Affect Schedule. To measure behavioral and neural responses related to cognitive flexibility, participants were required to complete a food-related switching task, and their brain activities were recorded through the technique of electroencephalography (EEG). Here we analyzed two widely investigated components-the N2 and P3 components that separately relate to conflict monitoring and response inhibition. RESULTS: The behavioral performance of food-related task switching did not show significant between-group differences. However, in comparison to NREs and SREs, UREs elicited larger N2 and lower P3 amplitudes during task switching. In addition, UREs exhibited a lower level of Neuroticism than SREs and NREs. Furthermore, food-related task switching induced N2 amplitude fully mediated the association between Neuroticism and disinhibited eating behavior in restrained eaters controlled for BMI and negative affect. Importantly, when a parallel mediation model with N2 and P3 was built concurrently, N2 was still able to fully mediate the association. CONCLUSION: According to behavioral and neural evidence, increased N2 amplitude induced by food-related task switching totally mediated the negative association between Neuroticism and disinhibited eating in restrained eaters.


Asunto(s)
Señales (Psicología) , Alimentos , Apetito , Cognición , Ingestión de Alimentos/psicología , Conducta Alimentaria/psicología , Femenino , Humanos
17.
J Am Chem Soc ; 144(28): 12816-12824, 2022 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-35802169

RESUMEN

The incorporation of secondary metal ions into Cu-exchanged SSZ-13 zeolites could improve their catalytic properties in selective catalytic reduction of NOx with ammonia (NH3-SCR), but their essential roles remain unclear at the molecular level. Herein, a series of Cu-Sm-SSZ-13 zeolites have been prepared by ion-exchanging Sm ions followed by Cu ions, which exhibit superior NH3-SCR performance. The NO conversion of Cu-Sm-SSZ-13 is nearly 10% higher than that of conventional Cu-SSZ-13 (175-250 °C) after hydrothermal ageing, showing an enhanced low-temperature activity. The Sm ions are found to occupy the six-membered rings (6MRs) of SSZ-13 by X-ray diffraction Rietveld refinement and aberration-corrected scanning transmission electron microscopy. The Sm ions at 6MRs can facilitate the formation of more active [ZCu2+(OH)]+ ions at 8MRs, as revealed by temperature-programmed reduction of hydrogen. X-ray photoelectron spectroscopy and density functional theory (DFT) calculations indicate that there exists electron transfer from Sm3+ to [ZCu2+(OH)]+ ions, which promotes the activity of [ZCu2+(OH)]+ ions by decreasing the activation energy of the formation of intermediates (NH4NO2 and H2NNO). Meanwhile, the electrostatic interaction between Sm3+ and [ZCu2+(OH)]+ results in a high-reaction energy barrier for transforming [ZCu2+(OH)]+ ions into inactive CuOx species, thus enhancing the stability of [ZCu2+(OH)]+ ions. The influence of the ion-exchanging sequence of Sm and Cu ions into SSZ-13 is further investigated by combining both experiments and theoretical calculations. This work provides a mechanistic insight of secondary ions in regulating the distribution, activity, and stability of Cu active sites, which is helpful for the design of high-performance Cu-SSZ-13 catalysts for the NH3-SCR reaction.

18.
BMC Ophthalmol ; 22(1): 322, 2022 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-35883160

RESUMEN

PURPOSE: To describe the genetic and clinical features of nineteen patients from eleven unrelated Chinese pedigrees with OPA1-related autosomal dominant optic atrophy (ADOA) and define the phenotype-genotype correlations. METHODS: Detailed ophthalmic examinations were performed. Targeted next-generation sequencing (NGS) was conducted in the eleven probands using a custom designed panel PS400. Sanger sequencing and cosegregation were used to verify the identified variants. The pathogenicity of gene variants was evaluated according to American College of Medical Genetics and Genomics (ACMG) guidelines. RESULTS: Nineteen patients from the eleven unrelated Chinese ADOA pedigrees had impaired vision and optic disc pallor. Optical coherence tomography showed significant thinning of the retinal nerve fiber layer. The visual field showed varying degrees of central or paracentral scotoma. The onset of symptoms occurred between 3 and 24 years of age (median age 6 years). Eleven variants in OPA1 were identified in the cohort, and nine novel variants were identified. Among the novel variants, two splicing variants c.984 + 1_984 + 2delGT, c.1194 + 2 T > C, two stop-gain variants c.1937C > G, c.2830G > T, and one frameshift variant c.2787_2794del8, were determined to be pathogenic based on ACMG. A novel splicing variant c.1316-10 T > G was determined to be likely pathogenic. In addition, a novel missense c.1283A > C (p.N428T) and two novel splicing variants c.2496G > A and c.1065 + 5G > C were of uncertain significance. CONCLUSIONS: Six novel pathogenic variants were identified. The findings will facilitate genetic counselling by expanding the pathogenic mutation spectrum of OPA1.


Asunto(s)
Atrofia Óptica Autosómica Dominante , GTP Fosfohidrolasas/genética , Estudios de Asociación Genética , Humanos , Mutación , Atrofia Óptica Autosómica Dominante/genética , Atrofia Óptica Autosómica Dominante/patología , Linaje
19.
Artículo en Inglés | MEDLINE | ID: mdl-35656812

RESUMEN

Reducing the dark current density and enhancing the overall performance of the device is the focal point in research for organic photodetectors. Two novel random terpolymers (P3 and P4) with different molecular weights are synthesized and evaluated as acceptors in bulk heterojunction (BHJ) polymer photodetectors. Compared with known acceptor materials, such as N2200 (P1) and F-N2200 (P2), polymer P4 has a lower lowest unoccupied molecular orbital (LUMO) energy level, favorable morphology, and good miscibility with a donor material J71, which leads to proper phase separation of the blend film and better dissociation of excitons and transport of carriers. Therefore, a considerably low dark current density (Jd) of 1.9 × 10-10 A/cm2 and a high specific detectivity (D*) of 1.8 × 1013 cm Hz1/2/W (also "Jones") at 580 nm under a -0.1 V bias are realized for the P4-based photodetector. More importantly, the device also exhibits a fast response speed (τr/τf = 1.24/1.87 µs) and a wide linear dynamic range (LDR) of 109.2 dB. This work demonstrates that high-performance all-polymer photodetectors with ideal morphology can be realized by random polymer acceptors with a fine-tuned molecular weight.

20.
J Trauma Acute Care Surg ; 92(6): 997-1004, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35609289

RESUMEN

BACKGROUND: Tourniquet use for extremity hemorrhage control has seen a recent increase in civilian usage. Previous retrospective studies demonstrated that tourniquets improve outcomes for major extremity trauma (MET). No prospective study has been conducted to date. The objective of this study was to evaluate outcomes in MET patients with prehospital tourniquet use. We hypothesized that prehospital tourniquet use in MET decreases the incidence of patients arriving to the trauma center in shock. METHODS: Data were collected prospectively for adult patients with MET at 26 Level I and 3 Level II trauma centers from 2015 to 2020. Limbs with tourniquets applied in the prehospital setting were included in the tourniquet group and limbs without prehospital tourniquets were enrolled in the control group. RESULTS: A total of 1,392 injured limbs were enrolled with 1,130 tourniquets, including 962 prehospital tourniquets. The control group consisted of 262 limbs without prehospital tourniquets and 88 with tourniquets placed upon hospital arrival. Prehospital improvised tourniquets were placed in 42 patients. Tourniquets effectively controlled bleeding in 87.7% of limbs. Tourniquet and control groups were similarly matched for demographics, Injury Severity Score, and prehospital vital signs (p > 0.05). Despite higher limb injury severity, patients in the tourniquet group were less likely to arrive in shock compared with the control group (13.0% vs. 17.4%, p = 0.04). The incidence of limb complications was not significantly higher in the tourniquet group (p > 0.05). CONCLUSION: This study is the first prospective analysis of prehospital tourniquet use for civilian extremity trauma. Prehospital tourniquet application was associated with decreased incidence of arrival in shock without increasing limb complications. We found widespread tourniquet use, high effectiveness, and a low number of improvised tourniquets. This study provides further evidence that tourniquets are being widely and safely adopted to improve outcomes in civilians with MET. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level IV.


Asunto(s)
Servicios Médicos de Urgencia , Extremidades/lesiones , Hemorragia/prevención & control , Torniquetes , Adulto , Hemorragia/etiología , Hemorragia/terapia , Humanos , Estudios Prospectivos , Estudios Retrospectivos , Choque/prevención & control , Torniquetes/efectos adversos , Centros Traumatológicos , Heridas y Lesiones/complicaciones
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