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1.
Org Biomol Chem ; 22(31): 6352-6361, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39044718

RESUMEN

Mechanisms for the Csp-H silylation between prop-2-yn-1-ylcyclohexane and triethylsilane, catalyzed by MOH/MH (M = Na or K), were investigated at the M06-L-D3/ma-def2-TZVP level. The SMD model was applied to simulate the solvent effect of 1,2-dimethoxyethane (DME). Computational results suggested that the Csp-H activation of prop-2-yn-1-ylcyclohexane could be achieved by MOH to generate R-CC-M compounds, which continued to react with triethylsilane to yield the final product: (3-cyclohexylprop-1-yn-1-yl) triethylsilane. Moreover, analysis of the Gibbs free energy surface of the three reactions suggested that a path with the participation of LiOH had the highest energy barrier, which was consistent with experimental results showing that only a small amount of product had been formed. The obtained KH could interact readily with the H2O molecule with a much lower energy barrier (0.6 kcal mol-1) than that using the path with prop-2-yn-1-ylcyclohexane. Furthermore, compared to MOH, MH could catalyze the reaction with lower energy barriers, and the reactions became exothermic, thereby benefiting the reaction. Finally, the mechanism for obtaining the byproduct (prop-1-yn-1-ylcyclohexane) was posited: it had a higher energy barrier than the path to yield the main product. Frontier orbital, noncovalent interactions (NCI), Fukui function and dual descriptor analyses could be used to analyze the structure and reveal the reaction substances.

2.
Chemosphere ; 364: 142973, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39084305

RESUMEN

Phosphate discharge in sewage can result in water eutrophication, posing a threat to aquatic ecosystems. Membrane capacitive deionization (MCDI) has demonstrated outstanding performance and significant potential for salt removal and nutrient recovery. In this study, a nitrogen-doped activated carbon electrode material (NAC) was synthesized through one-step pyrolysis to selectively remove phosphate from MCDI. At a voltage of 1.2V, a flow rate of 20 mL/min, and a pH of 6.51, the phosphate adsorption capacity of the NAC electrode was determined to be 1.60 mg/g. The study revealed that NAC pHpzc increased from 4.14 to 6.44, effectively broadening the pH range for phosphate removal. In the presence of competing ions (NO3-, Cl-, and SO42-) at a concentration of 0.5 M, the electroadsorption capacity of phosphate decreased to 1.21 mg/g, 1.14 mg/g, and 1.02 mg/g, respectively. The kinetic parameters of adsorption indicated that NAC electroadsorbed phosphate through physical adsorption, with the maximum adsorption capacity achieved at 303K. Data from the Freundlich isothermal model suggested that phosphate adsorption by the NAC electrode involves a multilayer adsorption process. A carbon structure model of density functional theory (DFT), incorporating doped nitrogen, was constructed based on XPS analysis. Following nitrogen doping, the electrostatic potential (ESP) of unsaturated carbon atoms became more positive, enhancing the ability of nitrogen-doped activated carbon to adsorb phosphate. This study provides compelling evidence that nitrogen doping facilitates the adsorption of phosphate by carbon materials.

3.
Rev Cardiovasc Med ; 25(1): 22, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39077667

RESUMEN

Advances in cancer treatment have increased patient survival rates, shifting clinical focus towards minimizing treatment-related morbidity, including cardiovascular issues. Since echocardiography allows for a comprehensive non-invasive assessment at all cancer stages, it is well suited to monitor cardiovascular disease secondary to oncology treatment. This has earned it significant attention in the study of cardiac tumors and treatment-induced cardiac alterations. Ultrasound methods-ranging from transthoracic and transesophageal echocardiography to ultrasound diagnostic techniques including myocardial strain imaging, myocardial work indices, three-dimensional cardiac imaging-offer a holistic view of both the tumor and its treatment impact cardiac function. Stress echocardiography, myocardial contrast echocardiography, and myocardial acoustic angiography further augment this capability. Together, these echocardiographic techniques provide clinicians with early detection opportunities for cardiac damage, enabling timely interventions. As such, echocardiography continues to be instrumental in monitoring and managing the cardiovascular health of oncology patients, complementing efforts to optimize their overall treatment and survival outcomes.

4.
Campbell Syst Rev ; 20(2): e1416, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38882932

RESUMEN

This is the protocol for an updated Campbell systematic review. The objectives are as follows: To evaluate the effect of behavioral interventions on smoking cessation among homeless individuals.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38935470

RESUMEN

Ubiquitous sensing from wearable devices in the wild holds promise for enhancing human well-being, from diagnosing clinical conditions and measuring stress to building adaptive health promoting scaffolds. But the large volumes of data therein across heterogeneous contexts pose challenges for conventional supervised learning approaches. Representation Learning from biological signals is an emerging realm catalyzed by the recent advances in computational modeling and the abundance of publicly shared databases. The electrocardiogram (ECG) is the primary researched modality in this context, with applications in health monitoring, stress and affect estimation. Yet, most studies are limited by small-scale controlled data collection and over-parameterized architecture choices. We introduce WildECG, a pre-trained state-space model for representation learning from ECG signals. We train this model in a self-supervised manner with 275 000 10 s ECG recordings collected in the wild and evaluate it on a range of downstream tasks. The proposed model is a robust backbone for ECG analysis, providing competitive performance on most of the tasks considered, while demonstrating efficacy in low-resource regimes.

6.
Biomacromolecules ; 25(6): 3671-3684, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38720431

RESUMEN

Reactive oxygen species (ROS) have emerged as a promising treatment option for antibacterial and biofilm eradication. However, their therapeutic efficacy is significantly hampered by the unique microenvironments of diabetic wounds. In this study, we designed and synthesized porphyrin-based Fe covalent organic frameworks (Fe-COF) through a Schiff base condensation reaction. Subsequently, Fe-COF were encapsulated with hyaluronic acid (HA) through electrostatic adsorption, resulting in a novel formulation named HA-Fe-COF for diabetic wound healing. HA-Fe-COF were engineered to respond to hyaluronidase in the infected wound, leading to the controlled release of Fe-COF. Those released Fe-COF served a dual role as photosensitizers, generating singlet oxygen and localized heating when exposed to dual light sources. Additionally, they acted as peroxidase-like nanozymes, facilitating the production of ROS through enzymatic reactions. This innovative approach enabled a synergistic therapeutic effect combining photodynamic, photothermal, and chemodynamic modalities. Furthermore, the sustained release of HA from HA-Fe-COF promoted angiogenesis, collagen deposition, and re-epithelialization during the diabetic wound healing process. This "all-in-one" strategy offers a novel approach for the development of antimicrobial and biofilm eradication strategies that minimize damage to healthy tissues in vivo.


Asunto(s)
Ácido Hialurónico , Estructuras Metalorgánicas , Porfirinas , Cicatrización de Heridas , Cicatrización de Heridas/efectos de los fármacos , Animales , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Porfirinas/química , Porfirinas/farmacología , Ratones , Especies Reactivas de Oxígeno/metabolismo , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/administración & dosificación , Fármacos Fotosensibilizantes/síntesis química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/administración & dosificación , Piel/efectos de los fármacos , Humanos , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/microbiología , Hierro/química , Fotoquimioterapia/métodos , Hialuronoglucosaminidasa
7.
J Environ Manage ; 360: 121101, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38761619

RESUMEN

Although our knowledge of national carbon emission trading system and green certificate trading system are powerful incentive instruments that can deliver on increasingly ambitious climate targets in China, there remains an uncertainty of systems' structural reforms. This study builds on and extends a well-established dynamic computable general equilibrium (CGE) model to incorporate carbon trading system and green certificate trading system into the modeling framework, simulating a diverse of system development pathways further allows an exploration of the many possible policy effect. Then, using total factor productivity as a comprehensive indicator to asses policy effectiveness, the evolutionary trend of comprehensive effects under different paths are separately evaluated to discover the reforms' optimal range. Our work offers main results: First, these instruments provide a price signal. The introduction of a carbon allowance auction drive up carbon prices, while the implementation of a green certificate punishment and the expansion of the trading scope promote an increase in green certificate prices. Second, all policy scenarios that help reduce carbon emission intensity and optimize the power supply structure. However, in achieving the net-zero goal, the green certificate policy incurs more economic costs than the carbon trading policy. Indeed, the combination of multiple policy tools alleviates the decline of social welfare levels. Third, synergism design among policy tools: the focus should be on carbon trading policy from 2021 to 2030, green certificate trading policy from 2030 to 2050, and strengthened policy from 2050 to 2060. Reform measures within policies may need to be introduced in a timely manner. This study offers specific insights and tailored policy proposals to support policymakers in balancing environmental goals with economic and social needs in light of the aforementioned findings.


Asunto(s)
Carbono , China
9.
Small ; 20(29): e2310247, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38368267

RESUMEN

Chemodynamic therapy (CDT) has emerged as a promising approach for treating infected diabetic wounds, while reliable imaging technology for simultaneous monitoring of ROS and therapeutic processes is still a formidable challenge. Herein, smart covalent organic framework (COF) nanoreactors (COF NRs) are constructed by hyaluronic acid (HA) packaged glucose oxidase (GOx) covalently linked Fe-COF for diabetic wound healing. Upon the breakdown of the HA protective layer, GOx consumes glucose to produce gluconic acid and hydrogen peroxide (H2O2), resulting in decreased local pH and H2O2 supplementation. Density functional theory (DFT) calculations show that Fe-COF has high catalytic activity towards H2O2, leading to in situ generation of hydroxyl radicals (·OH) for sterilization, and the localized downregulation of glucose effectively improved the microenvironment of diabetic wounds. Meanwhile, based on the near-infrared photothermal imaging of oxidized 3,3',5,5'-tetramethylbenzidine (oxTMB), the authors showed that TMB can be applied for the point-of-care testing of ·OH and glucose, and assessing the sterilization progress in vivo. More significantly, the facile photothermal signaling strategy can be extended to monitor various ROS-mediated therapeutic systems, enabling accurate prediction of treatment outcomes.


Asunto(s)
Especies Reactivas de Oxígeno , Cicatrización de Heridas , Cicatrización de Heridas/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Animales , Glucosa Oxidasa/metabolismo , Glucosa Oxidasa/química , Peróxido de Hidrógeno/química , Esterilización/métodos , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Ratones , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Glucosa
10.
Sci Data ; 10(1): 503, 2023 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-37516756

RESUMEN

We present data from the Heart Rate Variability and Emotion Regulation (HRV-ER) randomized clinical trial testing effects of HRV biofeedback. Younger (N = 121) and older (N = 72) participants completed baseline magnetic resonance imaging (MRI) including T1-weighted, resting and emotion regulation task functional MRI (fMRI), pulsed continuous arterial spin labeling (PCASL), and proton magnetic resonance spectroscopy (1H MRS). During fMRI scans, physiological measures (blood pressure, pulse, respiration, and end-tidal CO2) were continuously acquired. Participants were randomized to either increase heart rate oscillations or decrease heart rate oscillations during daily sessions. After 5 weeks of HRV biofeedback, they repeated the baseline measurements in addition to new measures (ultimatum game fMRI, training mimicking during blood oxygen level dependent (BOLD) and PCASL fMRI). Participants also wore a wristband sensor to estimate sleep time. Psychological assessment comprised three cognitive tests and ten questionnaires related to emotional well-being. A subset (N = 104) provided plasma samples pre- and post-intervention that were assayed for amyloid and tau. Data is publicly available via the OpenNeuro data sharing platform.


Asunto(s)
Biorretroalimentación Psicológica , Neuroimagen , Humanos , Bioensayo , Presión Sanguínea , Frecuencia Cardíaca , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
STAR Protoc ; 4(2): 102238, 2023 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-37083322

RESUMEN

Detection of radioactive iodide ions (I-) is important for protecting human beings from the hazards of radioactive pollution. Herein, we present a protocol for detecting I- using a zirconium(IV)-enhanced strategy. We describe steps for optimizing the I- detection approach, establishing standard curves, and finally applying the approach. The use of zirconium(IV) greatly improves the detection performance and endows this approach with an ultralow detection limit of 0.176 nM together with wide applicability in various aqueous environments. For complete details on the use and execution of this protocol, please refer to Feng et al. (2022).1.

12.
J Hazard Mater ; 445: 130620, 2023 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-37056004

RESUMEN

The highly effective utilization of uranium resources in global seawater is a viable method to satisfy the rising demands for fueling nuclear energy industry. Herein, inspired by the multi-mechanisms of the marine bacteria for uranium immobilization, CdS nanoparticles are deposited on the cell of marine bacterial strain Bacillus velezensis UUS-1 to create a photosensitized biohybrid system UUS-1/CdS. This system achieves high uranium extraction efficiency using a cascaded strategy, where the bacterial cells guarantee high extraction selectivity and the photosensitive CdS nanoparticles realize cascading photoreduction of high soluble U(VI) to low soluble U(IV) to enhance extraction capacity. As one of the fastest-acting adsorbents in natural seawater, a high extraction capacity for uranium of 7.03 mg g-1 is achieved with an ultrafast extraction speed of 4.69 mg g-1 d-1. The cascaded strategy promisingly improves uranium extraction performance and pioneers a new direction for the design of adsorbents to extract uranium from seawater.


Asunto(s)
Uranio , Agua de Mar
13.
Antioxidants (Basel) ; 12(3)2023 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-36978948

RESUMEN

The enzyme 1-acylglycerol-3-phosphate O-acyltransferase 2 (AGPAT2) is an intermediate enzyme in triglyceride synthesis. The aim was to study the regulatory mechanism of AGPAT2 on Nile tilapia, Oreochromis niloticus. In this study, antisense RNA technology was used to knock-down AGPAT2 in Nile tilapia. Compared with the control groups (transfected with ultrapure water or the blank expression vector), the AGPAT2 knock-down group showed a significantly higher weight gain rate, special growth rate, visceral somatic index, and hepatopancreas somatic index; and significantly increased the total cholesterol, triglycerides, glucose, low-density lipoprotein cholesterol, and insulin levels in serum. In addition, the contents of total cholesterol and triglycerides and the abundance of superoxide dismutase, catalase, and glutathione peroxidase in the liver significantly increased, while the malondialdehyde content significantly decreased. The liver cells became severely vacuolated and accumulated lipids in the AGPAT2 knock-down group. Comparative transcriptome analyses (AGPAT2 knock-down vs. control group) revealed 1789 differentially expressed genes (DEGs), including 472 upregulated genes and 1313 downregulated genes in the AGPAT2 knock-down group. Functional analysis showed that the main pathway of differentially expressed genes enrichment was lipid metabolism and oxidative stress, such as steroid biosynthesis, unsaturated fatty acid biosynthesis, the PPAR signaling pathway, and the P53 pathway. We used qRT-PCR to verify the mRNA expression changes of 13 downstream differential genes in related signaling pathways. These findings demonstrate that knock-down of AGPAT2 in tilapia leads to abnormal lipid metabolism and oxidative stress.

14.
J Colloid Interface Sci ; 636: 618-626, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-36669455

RESUMEN

Recent experimental analysis indicates WO3-based nanostructures exhibit poor hydrogen evolution reactivity, particularly in alkaline medium, arising from the low electron transfer rate. It is imperative to tune the composition and structure of WO3 to boost the cleavage of H-OH bond. Here, we construct Ru/WO3-W2N/N-doped carbon sheets (Ru/WO3-W2N/NC) using m-WO3 nanosheets as precursors with the aid of RuCl3, Tris (hydroxymethyl) aminomethane, and dopamine. Structural investigation reveals the formation of N-doped carbon sheets, Ru nanoparticles, and WO3-W2N. As a result, hydrogen evolution reactivity is greatly improved on Ru/WO3-W2N/N-doped carbon sheets with 64 mV at 10 mA/cm2 in 1 mol/L (M) KOH, outperforming most of WO3-based electrocatalysts in previous literatures. Meanwhile, it facilitates the generation of H2 in 0.5 M H2SO4 with the excellent activity of 110 mV at 10 mA/cm2. Our work provides an efficient strategy to tailor the electronic structure of WO3 to catalyze acidic and alkaline hydrogen evolution reaction.

15.
Cogn Affect Behav Neurosci ; 23(1): 66-83, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36109422

RESUMEN

Heart rate variability is a robust biomarker of emotional well-being, consistent with the shared brain networks regulating emotion regulation and heart rate. While high heart rate oscillatory activity clearly indicates healthy regulatory brain systems, can increasing this oscillatory activity also enhance brain function? To test this possibility, we randomly assigned 106 young adult participants to one of two 5-week interventions involving daily biofeedback that either increased heart rate oscillations (Osc+ condition) or had little effect on heart rate oscillations (Osc- condition) and examined effects on brain activity during rest and during regulating emotion. While there were no significant changes in the right amygdala-medial prefrontal cortex (MPFC) functional connectivity (our primary outcome), the Osc+ intervention increased left amygdala-MPFC functional connectivity and functional connectivity in emotion-related resting-state networks during rest. It also increased down-regulation of activity in somatosensory brain regions during an emotion regulation task. The Osc- intervention did not have these effects. In this healthy cohort, the two conditions did not differentially affect anxiety, depression, or mood. These findings indicate that modulating heart rate oscillatory activity changes emotion network coordination in the brain.


Asunto(s)
Encéfalo , Emociones , Adulto Joven , Humanos , Frecuencia Cardíaca/fisiología , Emociones/fisiología , Corteza Prefrontal/fisiología , Amígdala del Cerebelo/fisiología , Imagen por Resonancia Magnética , Vías Nerviosas/fisiología , Mapeo Encefálico
16.
Appl Psychophysiol Biofeedback ; 48(1): 35-48, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36030457

RESUMEN

Previous research suggests that higher heart rate variability (HRV) is associated with better cognitive function. However, since most previous findings on the relationship between HRV and cognitive function were correlational in nature, it is unclear whether individual differences in HRV play a causal role in cognitive performance. To investigate whether there are causal relationships, we used a simple breathing manipulation that increases HRV through a 5-week HRV biofeedback intervention and examined whether this manipulation improves cognitive performance in younger and older adults (N = 165). The 5-week HRV biofeedback intervention did not significantly improve inhibitory control, working memory and processing speed across age groups. However, improvement in the Flanker score (a measure of inhibition) was associated with the amplitude of heart rate oscillations during practice sessions in the younger and older intervention groups. Our results suggest that daily practice to increase heart rate oscillations may improve inhibitory control, but future studies using longer intervention periods are warranted to replicate the present finding.


Asunto(s)
Biorretroalimentación Psicológica , Cognición , Humanos , Anciano , Frecuencia Cardíaca/fisiología , Biorretroalimentación Psicológica/métodos , Respiración
18.
Sci Data ; 9(1): 536, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-36050329

RESUMEN

The TILES-2019 data set consists of behavioral and physiological data gathered from 57 medical residents (i.e., trainees) working in an intensive care unit (ICU) in the United States. The data set allows for the exploration of longitudinal changes in well-being, teamwork, and job performance in a demanding environment, as residents worked in the ICU for three weeks. Residents wore a Fitbit, a Bluetooth-based proximity sensor, and an audio-feature recorder. They completed daily surveys and interviews at the beginning and end of their rotation. In addition, we collected data from environmental sensors (i.e., Internet-of-Things Bluetooth data hubs) and obtained hospital records (e.g., patient census) and residents' job evaluations. This data set may be may be of interest to researchers interested in workplace stress, group dynamics, social support, the physical and psychological effects of witnessing patient deaths, predicting survey data from sensors, and privacy-aware and privacy-preserving machine learning. Notably, a small subset of the data was collected during the first wave of the COVID-19 pandemic.


Asunto(s)
Internado y Residencia , Estrés Laboral , COVID-19 , Humanos , Unidades de Cuidados Intensivos , Pandemias
19.
Chem Commun (Camb) ; 58(63): 8830-8833, 2022 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-35848845

RESUMEN

Highly crystalline Fe-COFs were constructed from the building blocks carrying pyridyl-aldehyde and triamine moieties in the presence of Fe(OTf)2 and acetic acid under ambient conditions via a subcomponent assembly strategy. The spectral results prove the coordination of atomically distributed Fe(II) ions with the nitrogen species of covalently formed iminopyridine linkages.

20.
Environ Sci Pollut Res Int ; 29(54): 81970-81992, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35737262

RESUMEN

In order to achieve the emission peak and carbon neutrality ("30·60" goals), personal carbon trading may be included in China's carbon trading market in the future, based on the corporate-level carbon trading that is already in place. It will be an effective solution to reduce carbon emissions from the consumption side and can be used as a supplement to the corporate carbon trading mechanism and carbon tax. This study constructs a personal carbon trading system based on the fundamental realities of China, which includes four attributes: carbon quota acquisition, trading partner selection, low-carbon behavior offset mechanism, and value preservation mode. Through questionnaire survey and choice experiment, the logit model is used to analyze the influence of the four attributes upon the individual willingness to participate in personal carbon trading and the heterogeneity of the public on personal carbon trading in the context of carbon neutrality policy. The study found that the influence of the attributes on the willingness to participate was ranked as follows: carbon quota acquisition > value preservation mode > low-carbon behavior offset mechanism > trading partner selection. The level of knowledge about carbon neutrality and salary will have a significant positive impact on the attribute-level preference of personal carbon trading. Finally, suggestions are made for designing, applying, and promoting personal carbon trading mechanisms to improve the public's willingness to participate in personal carbon trading and perfect the construction of carbon trading systems at the consumption side. The take-home message of the study is that a well-established personal carbon trading mechanism is an effective solution for reducing greenhouse gas emissions.


Asunto(s)
Gases de Efecto Invernadero , Carbono/análisis , Objetivos , China , Motivación
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