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1.
Eur Geriatr Med ; 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39294507

RESUMEN

BACKGROUND: Diabetes mellitus (DM) and sarcopenia are bidirectionally linked and commonly co-occur among middle-aged and elderly individuals. This study aims to examine the combined effect of DM and sarcopenia on depressive symptoms and cognitive function. METHODS: This was a nationwide cohort study using data from the China Health and Retirement Longitudinal Study. The definition of DM was self-reported and based on hemoglobin A1c (HbA1c) ≥ 6.5% or fasting blood glucose (FBG) ≥ 126 mg/dL. The diagnosis of sarcopenia was based on the Asian Working Group for Sarcopenia 2019 algorithm. The outcomes included depressive symptoms assessed using the 10-item Center for Epidemiologic Studies Depression Scale (CES-D-10) and cognitive function. Multi-adjusted linear and logistic regression models were conducted to evaluate the combined effect of DM and sarcopenia on depression and cognitive performance. RESULTS: 9148 participants were included in the longitudinal analysis, with 45.5% being men and an average age of 57.4 years. 6987 (76.4%) participants had neither DM nor sarcopenia, 1076 (11.8%) had DM only, 983 (10.8%) had sarcopenia only, and 102 (1.1%) had both DM and sarcopenia. In the cross-sectional analysis, the DM (+)/Sarcopenia (+) group exhibited the highest CES-D-10 score (ß: 2.23, 95% confidence interval (CI): 1.26, 3.19) and the lowest cognitive score (ß: - 1.02, 95% CI - 1.79, - 0.26) (P for trend < 0.05). In the longitudinal analysis, individuals in the DM (+)/Sarcopenia ( +) group had higher risks of moderate-to-severe depression (odds ratio (OR): 2.09, 95% CI 1.18, 3.71) and cognitive decline (OR: 1.87, 95% CI 1.19, 2.95) compared to the DM (-)/Sarcopenia (-) group. The population attributable fractions of DM and sarcopenia were 42.2% (95% CI 6.3, 90.4) for moderate-to-severe depression and 23.0% (95% CI 8.6, 39.3) for cognitive decline. CONCLUSION: DM and sarcopenia additively increase the risk of moderate-to-severe depression and cognitive impairment, highlighting the importance of vigilant monitoring and management of these conditions to preserve mental health in middle-aged and elderly individuals.

2.
Plant Biotechnol J ; 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39283921

RESUMEN

The cotton genus comprises both diploid and allotetraploid species, and the diversity in petal colour within this genus offers valuable targets for studying orthologous gene function differentiation and evolution. However, the genetic basis for this diversity in petal colour remains largely unknown. The red petal colour primarily comes from C, G, K, and D genome species, and it is likely that the common ancestor of cotton had red petals. Here, by employing a clone mapping strategy, we mapped the red petal trait to a specific region on chromosome A07 in upland cotton. Genomic comparisons and phylogenetic analyses revealed that the red petal phenotype introgressed from G. bickii. Transcriptome analysis indicated that GhRPRS1, which encodes a glutathione S-transferase, was the causative gene for the red petal colour. Knocking out GhRPRS1 resulted in white petals and the absence of red spots, while overexpression of both genotypes of GhRPRS1 led to red petals. Further analysis suggested that GhRPRS1 played a role in transporting pelargonidin-3-O-glucoside and cyanidin-3-O-glucoside. Promoter activity analysis indicated that variations in the promoter, but not in the gene body of GhRPRS1, have led to different petal colours within the genus. Our findings provide new insights into orthologous gene evolution as well as new strategies for modifying promoters in cotton breeding.

3.
Brain Imaging Behav ; 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39269599

RESUMEN

Insomnia is a widespread health problem among adults, and it impairs cognitive control and emotional regulation functions. Stress and insomnia are positively correlated, and their vicious cycle has been widely reported. In this study, we explore the neural biomarkers of insomnia from the perspective of whole-brain functional connectivity and investigate the neural mechanisms underlying the association between stress and insomnia. The current study was conducted on a cross-sectional sample (N = 430). First, we investigated the correlation between perceived stress and insomnia. Second, we applied connectome-based predictive modeling (CPM) to determine the neuromarkers of insomnia. Finally, we explored the neural basis underlying the association between perceived stress and insomnia. A significant positive correlation was found between perceived stress and insomnia in the present research. Results of CPM revealed the following as the neural substrates supporting insomnia: the emotion regulation circuit involving repetitive negative thinking and the cognitive control circuit involving attention control. According to further results from mediation analysis, the frontoparietal network supporting cognitive emotion regulation is an important neural mechanism that maintains the correlation between stress and insomnia. The present study offers a profound insight into the alterations of brain activity related to insomnia, and it further investigates the neural underpinnings of the robust association between stress and insomnia. This study also opens new avenues for neural interventions to alleviate stress-related insomnia.

5.
BMJ Open ; 14(8): e087142, 2024 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-39181552

RESUMEN

INTRODUCTION: Osteoporotic fractures are a leading cause of disability and contribute significantly to medical care costs worldwide. Variations in bone mineral density and the risk of osteoporosis are notably influenced by altitude. This study aims to longitudinally examine individuals with osteoporosis and low bone mass at three different altitudes (low, high and very high) to understand the effects of high-altitude environments on bone density. METHODS AND ANALYSIS: This multicentre, prospective cohort study will involve 893 participants divided into three groups based on altitude: low (500-1500 m), high (2500-4500 m) and very high (4500-5500 m). Participants will undergo comprehensive diagnostic assessments, including demographic data collection, structured questionnaires, medical examinations and clinical laboratory tests. Follow-up visits will occur annually for a minimum of 5 years. The primary outcome will be changes in bone mineral density values. Secondary outcomes will include the incidence of osteoporosis and osteoporotic fractures. Cox proportional hazard models will be used to calculate the risk associated with osteoporotic events and related fractures. ETHICS AND DISSEMINATION: The study has been approved by the Institutional Review Board of the Hospital of Chengdu Office of People's Government of Tibetan Autonomous Region (No: 2024-70). The acquired insights will be disseminated via academic forums, scholarly articles and stakeholder engagement sessions. TRIAL REGISTRATIONNUMBER: ChiCTR2300078872.


Asunto(s)
Altitud , Densidad Ósea , Osteoporosis , Fracturas Osteoporóticas , Humanos , Osteoporosis/epidemiología , Estudios Prospectivos , Persona de Mediana Edad , Femenino , Anciano , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/etiología , Masculino , Estudios Multicéntricos como Asunto , China/epidemiología , Factores de Riesgo , Proyectos de Investigación
6.
Environ Technol ; : 1-15, 2024 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-39128838

RESUMEN

ABSTRACTDrought presents a major challenge to the management of rocky desertification and ecological restoration in the delicate karst ecosystems of Guangxi. In this study, the normalized difference vegetation index (NDVI), fractional vegetation cover (FVC) and net primary productivity (NPP) were selected as vegetation remote sensing parameters, and the spatial response characteristics of different types of vegetation in karst areas of Guangxi Province to light, moderate, severe and extreme drought were analyzed to provide scientific basis for the evaluation of the impact of drought on vegetation in karst areas. The results are as follows: (1) NDVI, FVC and NPP showed a fluctuating increasing trend from 2000 to 2022, and the increasing rates were 0.058, 6.90%, and 43.3gC.m-2 per decade respectively. During this period, the number of light, moderate and severe drought days showed a decreasing trend, but the number of extreme drought days tended to increase. (2) The negative correlation of NDVI, FVC and NPP and drought increased from moderate to extreme drought, and from light to extreme drought, the negative correlation between NDVI and FVC and drought decreased, while that of NPP increased. (3) Light and moderate droughts had obvious negative impact on Chinese fir and broad-leaved forest, whereas severe and extreme droughts had obvious negative effect on eucalyptus and bamboo forest.

7.
Molecules ; 29(16)2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39202927

RESUMEN

Aqueous zinc ion batteries (AZIBs) have received a lot of attention in electrochemical energy storage systems for their low cost, environmental compatibility, and good safety. However, cathode materials still face poor material stability and conductivity, which cause poor reversibility and poor rate performance in AZIBs. Herein, a heterogeneous structure combined with cation pre-intercalation strategies was used to prepare a novel CaV6O16·3H2O@Ni0.24V2O5·nH2O material (CaNiVO) for high-performance Zn storage. Excellent energy storage performance was achieved via the wide interlayer conductive network originating from the interlayer-embedded metal ions and heterointerfaces of the two-phase CaNiVO. Furthermore, this unique structure further showed excellent structural stability and led to fast electron/ion transport dynamics. Benefiting from the heterogeneous structure and cation pre-intercalation strategies, the CaNiVO electrodes showed an impressive specific capacity of 334.7 mAh g-1 at 0.1 A g-1 and a rate performance of 110.3 mAh g-1 at 2 A g-1. Therefore, this paper provides a feasible strategy for designing and optimizing cathode materials with superior Zn ion storage performance.

8.
Adv Mater ; : e2406856, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39177199

RESUMEN

Catalytic reactions mainly depend on the adsorption properties of reactants on the catalyst, which provides a perspective for the design of reversible lithium-carbon dioxide (Li-CO2) batteries including CO2 reduction (CO2RR) and CO2 evolution (CO2ER) reactions. However, due to the complex reaction process, the relationship between the adsorption configuration and CO2RR/CO2ER catalytic activity is still unclear in Li─CO2 batteries. Herein, taking Co3S4 as a model system, nickel (Ni substitution in the tetrahedral site to activate cobalt (Co) atom for forming multiatom catalytic domains in NiCo2S4 is utilized. Benefiting from the special geometric and electronic structures, NiCo2S4 exhibits an optimized adsorption configuration of lithium carbonate (Li2CO3), promoting its effective activation and decomposition. As a result, the Li-CO2 batteries with NiCo2S4 cathode exhibit remarkable electrochemical performance in terms of low potential gap of 0.42 V and high energy efficiency of 88.7%. This work provides a unique perspective for the development of highly efficient catalysts in Li-CO2 batteries.

9.
ACS Appl Mater Interfaces ; 16(31): 41684-41693, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39058923

RESUMEN

Very recently, the poor contact between the perovskite and carrier selective layer has been regarded as a critical issue for improving the performance and stability of perovskite solar cells (PSCs). In this study, the buried interface of regularly structured PSCs has been targeted. Glutathione-coated gold nanoparticles (GSH-AuNPs) are used as double-sided passivating agents to improve the quality of the perovskite films. It has been demonstrated that the GSH-AuNPs interact strongly with the SnO2 underlayer and the upper perovskite layer, significantly reducing the defect densities of this interface. Thus, the power conversion efficiency (PCE) of the PSCs can be increased from 20.46% (control, 19.38%, IPCE corrected) to 22.22% (GSH-AuNPs modified, 21.10%, IPCE corrected) with notable enhancement in Voc and FF. Moreover, the strong interaction between the C═O groups of GSH-AuNPs and the undercoordinated Pb2+ species of the perovskite films inhibits the formation of metallic Pb0. As a result, the unencapsulated GSH-AuNPs-modified devices retained 80% of their initial PCEs after 1000 h at ambient conditions, with a relative humidity (RH) of 60 ± 5%. UV-resistant PSCs have also been demonstrated after introducing GSH-AuNPs. Therefore, our findings demonstrate the bidirectional therapy strategy as a feasible approach for achieving efficient and UV-resistant PSCs.

10.
Sleep Med ; 121: 343-351, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39067150

RESUMEN

OBJECTIVE: To explore the association between insomnia symptoms and cognitive flexibility among undergraduates, along with its potential neural mechanisms. METHOD: A total of 102 participants were divided into insomnia (n = 55) and control (n = 47) groups based on sleep status. Cognitive flexibility was assessed using the Cognitive Flexibility Inventory (CFI) and the Number-Letter Task (N-L task). EEG data were recorded during the N-L task. RESULTS: The insomnia group exhibited lower CFI scores and higher switch costs in reaction time and accuracy compared to the control group. ERP analysis showed differences in P2, N2, and P3 component amplitudes between the two groups, with reduced N2 amplitude in the insomnia group under repeat trials. Time-frequency analysis revealed larger theta band event related synchronization in the frontal region and smaller theta band ERS in the parietal region under switch trials in the control group; the alpha band event-related desynchronization in the parietal region under repeat trials was significantly smaller in the control group compared to switch trials. CONCLUSION: Compared to undergraduates with normal sleep, those with insomnia symptoms exhibited reduced cognitive flexibility, which may be associated with some alterations in brain electrophysiological activities.


Asunto(s)
Cognición , Electroencefalografía , Potenciales Evocados , Trastornos del Inicio y del Mantenimiento del Sueño , Estudiantes , Humanos , Trastornos del Inicio y del Mantenimiento del Sueño/psicología , Trastornos del Inicio y del Mantenimiento del Sueño/fisiopatología , Masculino , Femenino , Potenciales Evocados/fisiología , Adulto Joven , Cognición/fisiología , Estudiantes/psicología , Estudiantes/estadística & datos numéricos , Tiempo de Reacción/fisiología , Adulto , Universidades
11.
World J Clin Cases ; 12(20): 4191-4198, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39015906

RESUMEN

BACKGROUND: Tuberculosis (TB) is a chronic respiratory infectious disease that considerably jeopardizes human health, and there is no effective vaccine suitable for its prevention in the entire population. AIM: To investigate the promotion of medication adherence and disease cognition in patients with drug-resistant (DR-)TB using detailed nursing management. METHODS: In total, 114 patients with DR-TB who were diagnosed and treated at our hospital between January 2019 and January 2023 were included in this study. Patients in the control group (n = 57) were managed with conventional nursing care, while those in the observation group (n = 57) were managed with detailed nursing care. Medication adherence, disease awareness scores, medication safety, and nursing satisfaction were compared between the two groups after the intervention. RESULTS: The post-intervention medication compliance rate was 91.23% in the observation group and 75.44% in the control group, with the former being 15.79% higher than the latter (P < 0.05). There was no statistically significant difference in the disease awareness scores between the two groups before the intervention; the disease awareness scores of the observation group were significantly higher than those of the control group after the intervention (P < 0.05). The incidence of gastrointestinal reactions, joint swelling and pain, hearing loss, electrolyte disorders, and liver and kidney function abnormalities were lower in the observation group than those in the control group. The total nursing satisfaction of the observation group was higher than that of the control group (P < 0.05). CONCLUSION: Implementation of detailed nursing management for patients with DR-TB can effectively improve medication adherence, enhance awareness of the disease, ensure safety of medication, and improve satisfaction with nursing care.

12.
Allergol Immunopathol (Madr) ; 52(4): 84-90, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38970270

RESUMEN

PURPOSE: To investigate the effect of metformin on gut microbiota imbalance in patients with type 2 diabetes mellitus (T2DM), and the value of probiotic supplementation. METHODS: A total of 84 newly diagnosed T2DM patients were randomly divided into probiotics group, metformin group, and control group, with 28 patients in each group. The blood glucose control, islet function, gut microbiota, and inflammatory factors were compared between three groups. RESULTS: After 3 months of treatment, fasting plasma glucose (FPG), 2-h postprandial plasma glucose (2-h PG), and glycosylated hemoglobin A1c (HbA1c) were evidently decreased in both probiotics and metformin groups (P < 0.05) and were lower than that in the control group prior to treatment. Besides, FPG, 2-h PG, and HbA1c were lower in the metformin group than that in the control group. FPG, 2-h PG, and HbA1c were further lower in the probiotic group than in the metformin group (P < 0.05). Fasting insulin (FINS) and islet ß cell (HOMA-ß) -function were dramatically increased in the same group (P < 0.05), while insulin-resistant islet ß cells (HOMA-IR) were significantly lower in the same group (P < 0.05); FINS and HOMA-ß were significantly higher, while HOMA-IR was significantly lower (P < 0.05) in both groups than in the control group prior to treatment. HOMA-IR was also lower in the probiotic group than in the metformin group after treatment (P < 0.05); the number of lactobacilli and bifidobacteria increased (P < 0.05) in both probiotic and metformin groups than in the control group prior to treatment, and the number of Enterobacteriaceae and Enterococcus was lower in the control group prior to treatment (P < 0.05). In addition, the number of lactobacilli and bifidobacteria was higher and the number of enterobacteria and enterococci was lower in the probiotic group than that in the metformin group after treatment, and the differences were statistically significant (P < 0.05). Lipopolysaccharide (LPS), interleukin 6 (IL-6), and C-reactive protein (CRP) levels were lower in both probiotic and metformin groups (P < 0.05). The serum LPS, IL-6, and CRP levels were lower in both probiotic and metformin groups, compared to the control group prior to the treatment (P < 0.05). CONCLUSION: Metformin while treating T2DM assists in improving the imbalance of gut microbiota.


Asunto(s)
Glucemia , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Hemoglobina Glucada , Hipoglucemiantes , Metformina , Probióticos , Humanos , Metformina/farmacología , Metformina/administración & dosificación , Probióticos/administración & dosificación , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/inmunología , Diabetes Mellitus Tipo 2/terapia , Diabetes Mellitus Tipo 2/microbiología , Microbioma Gastrointestinal/efectos de los fármacos , Microbioma Gastrointestinal/inmunología , Masculino , Femenino , Persona de Mediana Edad , Hipoglucemiantes/farmacología , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/uso terapéutico , Hemoglobina Glucada/metabolismo , Glucemia/efectos de los fármacos , Adulto , Suplementos Dietéticos , Insulina/sangre , Anciano
13.
Eur J Oncol Nurs ; 72: 102664, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-39059197

RESUMEN

PURPOSE: The incidence of breast cancer patients with negative body image has increased. However, research on interventions that explicitly reduce negative body image among breast cancer patients remains inadequate. The development of more pragmatic interventions is imperative. Therefore, we conducted this study to assess the effectiveness of a 6-week online Mindful Self-Compassion (MSC) intervention to reduce the negative body image in breast cancer patients. METHODS: We randomly assigned 64 female breast cancer patients to either the MSC group or the control group. The MSC group received a 6-week online Mindful Self-Compassion intervention, while the control group received no psychological training. Participants were surveyed by the Self-Compassion Scale-Short Form (SCS-SF), the Self-Acceptance Questionnaire (SAQ), the Chinese Perceived Stress Scale (CPSS), and the Body Image Scale (BIS) at baseline (T1), post-intervention (T2), and 1-month follow-up (T3). RESULTS: All outcome variables demonstrated significant time main effects and nonsignificant group main effects. The MSC and control groups had significant time × group interaction effects on self-compassion, self-acceptance, perceived stress, and negative body image. Simple main effects analysis revealed significant improvements in outcome variables at three-time points for the MSC group. CONCLUSION: A 6-week online Mindful Self-Compassion intervention can improve self-compassion and self-acceptance and reduce perceived stress and negative body image among the breast cancer patients in MSC group. Mindful Self-Compassion intervention shows promise as a viable way to maintain the mental well-being of breast cancer patients.

14.
Trials ; 25(1): 422, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38943177

RESUMEN

BACKGROUND: Bladder dysfunction, notably urinary retention, emerges as a significant complication for cervical cancer patients following radical hysterectomy, predominantly due to nerve damage, severely impacting their postoperative quality of life. The challenges to recovery include insufficient pelvic floor muscle training and the negative effects of prolonged postoperative indwelling urinary catheters. Intermittent catheterization represents the gold standard for neurogenic bladder management, facilitating bladder training, which is an important behavioral therapy aiming to enhance bladder function through the training of the external urethral sphincter and promoting the recovery of the micturition reflex. Nevertheless, gaps remain in current research regarding optimal timing for intermittent catheterization and the evaluation of subjective symptoms of bladder dysfunction. METHODS: Cervical cancer patients undergoing laparoscopic radical hysterectomy will be recruited to this randomized controlled trial. Participants will be randomly assigned to either early postoperative catheter removal combined with intermittent catheterization group or a control group receiving standard care with indwelling urinary catheters. All these patients will be followed for 3 months after surgery. The study's primary endpoint is the comparison of bladder function recovery rates (defined as achieving a Bladder Function Recovery Grade of II or higher) 2 weeks post-surgery. Secondary endpoints include the incidence of urinary tract infections, and changes in urodynamic parameters, and Mesure Du Handicap Urinaire scores within 1 month postoperatively. All analysis will adhere to the intention-to-treat principle. DISCUSSION: The findings from this trial are expected to refine clinical management strategies for enhancing postoperative recovery among cervical cancer patients undergoing radical hysterectomy. By providing robust evidence, this study aims to support patients and their families in informed decision-making regarding postoperative bladder management, potentially reducing the incidence of urinary complications and improving overall quality of life post-surgery. TRIAL REGISTRATION: ChiCTR2200064041, registered on 24th September, 2022.


Asunto(s)
Remoción de Dispositivos , Histerectomía , Cateterismo Uretral Intermitente , Laparoscopía , Ensayos Clínicos Controlados Aleatorios como Asunto , Recuperación de la Función , Vejiga Urinaria , Catéteres Urinarios , Neoplasias del Cuello Uterino , Humanos , Histerectomía/efectos adversos , Histerectomía/métodos , Femenino , Vejiga Urinaria/fisiopatología , Laparoscopía/efectos adversos , Neoplasias del Cuello Uterino/cirugía , Cateterismo Uretral Intermitente/efectos adversos , Factores de Tiempo , Remoción de Dispositivos/efectos adversos , Resultado del Tratamiento , Calidad de Vida , Urodinámica , Persona de Mediana Edad , Retención Urinaria/etiología , Retención Urinaria/terapia , Retención Urinaria/fisiopatología , Adulto , Cateterismo Urinario , Catéteres de Permanencia
15.
Int J Biol Macromol ; 273(Pt 1): 133041, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38857720

RESUMEN

The effects of soluble dietary fiber (SDF) from pomegranate peel obtained through enzyme (E-SDF) and alkali (A-SDF) extractions on the structural, physicochemical properties, and in vitro digestibility of sweet potato starch (SPS) were investigated. The expansion degree of SPS granules, pasting viscosity, gel strength and hardness were decreased after adding E-SDF. The setback was accelerated in the presence of A-SDF but E-SDF delayed this effect during the cooling of the starch paste. However, the addition of A-SDF significantly reduced the breakdown of SPS and improved the freeze-thaw stability of starch gels, even at low concentrations (0.1 %), while E-SDF showed the opposite result. The structural characterization of SDF-SPS mixtures showed that A-SDF can help SPS form an enhanced microstructure compared with E-SDF, while polar groups such as hydroxyl group in E-SDF may bind to leached amylose through hydrogen bonding, leading to a decrease in SPS viscoelasticity. In addition, the results of in vitro digestion analysis indicated that A-SDF and E-SDF could decreased the digestibility of SPS and increased the content of resistant starch, especially when 0.5 % E-SDF was added. This study provides a new perspective on the application of SDF from pomegranate peel in improving starch-based foods processing and nutritional characteristics.


Asunto(s)
Fibras de la Dieta , Ipomoea batatas , Granada (Fruta) , Solubilidad , Almidón , Ipomoea batatas/química , Granada (Fruta)/química , Almidón/química , Almidón/metabolismo , Viscosidad , Fenómenos Químicos , Digestión
16.
J Colloid Interface Sci ; 672: 338-349, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-38850861

RESUMEN

Phase change materials (PCMs) can store and release latent heat under the designed phased change temperature and have received substantial interest for energy conservation and thermal control purposes. The use of PCMs in the construction of constant temperature buildings can improve the comfortable environment and save more energy. However, the leakage of PCMs during phase change process limits the application of PCMs. In this paper, a series of PCMs microcapsules with controllable core numbers is synthesized with paraffin (37 ℃) as the core and cross-linked chitosan as the wall. The single-core phase-change microcapsules (S-PCM) and multicore phase-change microcapsules (M-PCM) were prepared by adjusting the preparation condition. The latent heat of S-PCM and M-PCM are 61.4 mJ mg-1 and 50.1 mJ mg-1, respectively. The S-PCM and M-PCM display good stability without paraffin leakage. In addition, the composite blocks of gypsum and S-PCM (GSCM) and M-PCM (GMCM) were prepared and the thermoregulatory effection was investigated, where the surface temperature of GSCM was 5-10 ℃ lower than that of pure gypsum block. PCMs may also have broad application space in electronics, cold chain, and other industries.

17.
Nanomicro Lett ; 16(1): 221, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38884840

RESUMEN

Considering the serious electromagnetic wave (EMW) pollution problems and complex application condition, there is a pressing need to amalgamate multiple functionalities within a single substance. However, the effective integration of diverse functions into designed EMW absorption materials still faces the huge challenges. Herein, reduced graphene oxide/carbon foams (RGO/CFs) with two-dimensional/three-dimensional (2D/3D) van der Waals (vdWs) heterostructures were meticulously engineered and synthesized utilizing an efficient methodology involving freeze-drying, immersing absorption, secondary freeze-drying, followed by carbonization treatment. Thanks to their excellent linkage effect of amplified dielectric loss and optimized impedance matching, the designed 2D/3D RGO/CFs vdWs heterostructures demonstrated commendable EMW absorption performances, achieving a broad absorption bandwidth of 6.2 GHz and a reflection loss of - 50.58 dB with the low matching thicknesses. Furthermore, the obtained 2D/3D RGO/CFs vdWs heterostructures also displayed the significant radar stealth properties, good corrosion resistance performances as well as outstanding thermal insulation capabilities, displaying the great potential in complex and variable environments. Accordingly, this work not only demonstrated a straightforward method for fabricating 2D/3D vdWs heterostructures, but also outlined a powerful mixed-dimensional assembly strategy for engineering multifunctional foams for electromagnetic protection, aerospace and other complex conditions.

18.
Sci Rep ; 14(1): 13167, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849513

RESUMEN

Exploring the spatial coupling relationship and interaction mechanism between green urbanization (GU) and tourism competitiveness (TC) is of great significance for promoting urban sustainable development. However, the lack of research on the interaction mechanism between GU and TC limits the formulation of effective environmental management policy and urban planning. Taking 734 counties in the Yellow River Basin (YRB) as the study area, this paper analyzes the spatial coupling relationship between GU and TC on the basis of comprehensive evaluation of GU and TC. Then, the interactive mechanism between GU and TC is systematically discussed, and the synergistic development strategy of the two is proposed. The results show that the GU level presents a multicore circle structure, with provincial capitals, prefecture-level urban districts and economically developed counties in east-central regions as high-value centers. The TC at county scale presents a multi-center spatial structure. Additionally, there is a significant positive spatial coupling between GU and TC in the YRB. The analysis further reveals that green urbanization level, social progress, population development, infrastructure construction, economic development quality, and eco-environmental protection has a observably influence on TC. Tourism competitiveness, service competitiveness, location competitiveness, resource competitiveness, market competitiveness, environmental influence, and talent competitiveness has a observably influence on GU. TC can promote GU, and the improvement of green urbanization level can support the development of tourism competitiveness. According to the spatial zoning method, 734 counties are divided into 6 categories, and the coordinated development strategy of GU and TC for each type of district is proposed.

19.
Anal Chem ; 96(21): 8416-8423, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38755966

RESUMEN

Nanogap-based plasmonic metal nanocrystals have been applied in surface-enhanced Raman scattering detection, while the closed and insufficient electromagnetic fields as well as the nonreproducible Raman signal of the substrate greatly restrict the actual application. Herein, a highly uniform Au/AgAu monolayer with abundant nanogaps and huge electromagnetic enhancement is prepared, which shows ultrasensitive and reproducible SERS detection. Au/AgAu with an inner nanogap is first prepared based on Au nanotriangles, and the nanogap is opened from the three tips via a subsequent etching process. The open-gap Au/AgAu displays much higher SERS efficiency than Au and Au/AgAu with an inner nanogap on detecting crystal violet due to the open-gap induced electromagnetic enhancement and improved molecular absorption. Furthermore, the open-gap Au/AgAu monolayer is prepared via interfacial self-assembly, which shows further improved SERS due to the dense and strong hotspots in the nanocavities induced by the electromagnetic coupling between adjacent open gaps. The monolayer possesses excellent signal stability, uniformity, and reproducibility. The analytic enhancement factor and relative standard deviation reach to 2.12 × 108 and 4.65% on detecting crystal violet, respectively. Moreover, the monolayer achieves efficient detection of thiram in apple juice, biphenyl-4-thiol, 4-mercaptobenzoic, melamine, and a mixed solution of four different molecules, showing great promise in practical detection.

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