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1.
Nano Lett ; 24(10): 3036-3043, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38415595

ABSTRACT

Zinc-iodine batteries (ZIBs) are promising candidates for ecofriendly, safe, and low-cost energy storage systems, but polyiodide shuttling and the complex cathode fabrication procedures have severely hindered their broader commercial usage. Herein, a protocol is developed using phospholipid-like oleylamine molecules for scalable production of Langmuir-Blodgett films, which allows the facile preparation of ZIB cathodes in less than 1 min. The resulting inhomogeneous cathode allows for the continuous conversion of iodine. Moreover, the amine group of the oleylamine molecule at the cathode is capable of producing [OA*I+]I3- charge-transfer complexes with iodine, which facilitates the rapid migration of iodine and results in a highly reversible iodine conversion process. Consequently, the as-prepared ZIBs can deliver over 2000 cycles at 0.5 mA cm-2 with a capacity retention of 75.3%. This work presents a novel, straightforward, and efficient method for the rapid construction of ZIBs.

2.
Traffic ; 23(3): 140-157, 2022 03.
Article in English | MEDLINE | ID: mdl-34994051

ABSTRACT

The extremely dynamic life cycle of gap junction connections requires highly efficient intracellular trafficking system especially designed for gap junction proteins, but the underlying mechanisms are largely unknown. Here, we identified that the COPII-associated proteins ERGIC2 (ER-Golgi intermediate compartment) and ERGIC3 are specifically required for the efficient intracellular transport of gap junction proteins in both Caenorhabditis elegans and mice. In the absence of Ergic2 or Ergic3, gap junction proteins accumulate in the ER and Golgi apparatus and the size of endogenous gap junction plaques is reduced. Knocking out the Ergic2 or Ergic3 in mice results in heart enlargement and cardiac malfunction accompanied by reduced number and size of connexin 43 (Cx43) gap junctions. Invertebrates' gap junction protein innexins share no sequence similarity with vertebrates' connexins. However, ERGIC2 and ERGIC3 could bind to gap junction proteins in both worms and mice. Characterization of the highly specialized roles of ERGIC2 and ERGIC3 in metazoans reveals how the early secretory pathway could be adapted to facilitate the efficient transport for gap junction proteins in vivo.


Subject(s)
Connexins , Golgi Apparatus , Animals , Connexins/metabolism , Gap Junctions/metabolism , Golgi Apparatus/metabolism , Mice , Secretory Pathway , Vesicular Transport Proteins
3.
Small ; 20(1): e2305009, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37641184

ABSTRACT

As a high energy density power system, lithium-carbon dioxide (Li-CO2 ) batteries play an important role in addressing the fossil fuel crisis issues and alleviating the greenhouse effect. However, the sluggish transformation kinetic of CO2 and the difficult decomposition of discharge products impede the achievement of large capacity, small overpotential, and long life span of the batteries, which require exploring efficient catalysts to resolve these problems. In this review, the main focus is on the hot spot regulation strategies of the catalysts, which include the modulation of the active sites, the designing of microstructure, and the construction of composition. The recent progress of promising catalysis with hot spot regulated strategies is systematically addressed. Critical challenges are also presented and perspectives to provide useful guidance for the rational design of highly efficient catalysts for practical advanced Li-CO2 batteries are proposed.

4.
Small ; : e2311703, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38459649

ABSTRACT

High tap density electrodes play a vital role in developing rechargeable batteries with high volumetric capacities, however, developing advanced electrodes with satisfied capacity, excellent structural stability, and achieving the resulted batteries with a high initial Coulombic efficiency (ICE) and good rate capability with long lifespan simultaneously, are still an intractable challenge. Herein, an ultrahigh ICE of 94.1% and stable cycling of carbon-free iron selenides anode is enabled with a high tap density of 2.57 g cm-3 up to 4000 cycles at 5 A g-1 through strain-modulating by constructing a homologous heterostructure. Systematical characterization and theoretical calculation show that the self-adaptive homologous heterointerface alleviates the stress of the iron selenide anodes during cycling processes and subsequently improves the stability of the assembled batteries. Additionally, the well-formed homologous heterostructure also contributes to the rapid Na+ diffusion kinetic, increased charge transfer, and good reversibility of the transformation reactions, endowing the appealing rate capability of carbon-free iron selenides. The proposed design strategy provides new insight and inspiration to aid in the ongoing quest for advanced electrode materials with high tap densities and excellent stability.

5.
J Am Chem Soc ; 145(39): 21387-21396, 2023 Oct 04.
Article in English | MEDLINE | ID: mdl-37728869

ABSTRACT

The electrocatalytic nitrate (NO3-) reduction reaction (eNITRR) is a promising method for ammonia synthesis. However, its efficacy is currently limited due to poor selectivity, largely caused by the inherent complexity of the multiple-electron processes involved. To address these issues, oxygen-vacancy-rich LaFe0.9M0.1O3-δ (M = Co, Ni, and Cu) perovskite submicrofibers have been designed from the starting material LaFeO3-δ (LF) by a B-site substitution strategy and used as the eNITRR electrocatalyst. Consequently, the LaFe0.9Cu0.1O3-δ (LF0.9Cu0.1) submicrofibers with a stronger Fe-O hybridization, more oxygen vacancies, and more positive surface potential exhibit a higher ammonia yield rate of 349 ± 15 µg h-1 mg-1cat. and a Faradaic efficiency of 48 ± 2% than LF submicrofibers. The COMSOL Multiphysics simulations demonstrate that the more positive surface of LF0.9Cu0.1 submicrofibers can induce NO3- enrichment and suppress the competing hydrogen evolution reaction. By combining a variety of in situ characterizations and density functional theory calculations, the eNITRR mechanism is revealed, where the first proton-electron coupling step (*NO3 + H+ + e- → *HNO3) is the rate-determining step with a reduced energy barrier of 1.83 eV. This work highlights the positive effect of cation substitution in promoting eNITRR properties of perovskites and provides new insights into the studies of perovskite-type electrocatalytic ammonia synthesis catalysts.

6.
PLoS Genet ; 16(9): e1008704, 2020 09.
Article in English | MEDLINE | ID: mdl-32986702

ABSTRACT

ER stress occurs in many physiological and pathological conditions. However, how chronic ER stress is alleviated in specific cells in an intact organism is an outstanding question. Here, overexpressing the gap junction protein UNC-9 (Uncoordinated) in C. elegans neurons triggers the Ire1-Xbp1-mediated stress response in an age-dependent and cell-autonomous manner. The p38 MAPK PMK-3 regulates the chronic stress through IRE-1 phosphorylation. Overexpressing gap junction protein also activates autophagy. The insulin pathway functions through autophagy, but not the transcription of genes encoding ER chaperones, to counteract the p38-Ire1-Xbp1-mediated stress response. Together, these results reveal an intricate cellular regulatory network in response to chronic stress in a subset of cells in multicellular organism.


Subject(s)
Autophagy/physiology , Caenorhabditis elegans Proteins/metabolism , Caenorhabditis elegans/cytology , Endoplasmic Reticulum Stress/physiology , Insulin/metabolism , Neurons/metabolism , Animals , Animals, Genetically Modified , Caenorhabditis elegans/metabolism , Caenorhabditis elegans Proteins/genetics , Carrier Proteins/genetics , Carrier Proteins/metabolism , Green Fluorescent Proteins/genetics , Heat-Shock Proteins/genetics , Heat-Shock Proteins/metabolism , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mitogen-Activated Protein Kinases/genetics , Mitogen-Activated Protein Kinases/metabolism , Mutation , Phosphorylation , Protein Serine-Threonine Kinases/genetics , Protein Serine-Threonine Kinases/metabolism , Receptor, Insulin/genetics , Receptor, Insulin/metabolism , Stress, Physiological , Unfolded Protein Response/physiology
7.
Angew Chem Int Ed Engl ; 62(27): e202218122, 2023 Jul 03.
Article in English | MEDLINE | ID: mdl-37081751

ABSTRACT

Competition from hydrogen/oxygen evolution reactions and low solubility of N2 in aqueous systems limited the selectivity and activity on nitrogen fixation reaction. Herein, we design an aerobic-hydrophobic Janus structure by introducing fluorinated modification on porous carbon nanofibers embedded with partially carbonized iron heterojunctions (Fe3 C/Fe@PCNF-F). The simulations prove that the Janus structure can keep the internal Fe3 C/Fe@PCNF-F away from water infiltration and endow a N2 molecular-concentrating effect, suppressing the competing reactions and overcoming the mass-transfer limitations to build a robust "quasi-solid-gas" state micro-domain around the catalyst surface. In this proof-of-concept system, the Fe3 C/Fe@PCNF-F exhibits excellent electrocatalytic performance for nitrogen fixation (NH3 yield rate up to 29.2 µg h-1 mg-1 cat. and Faraday efficiency (FE) up to 27.8 % in nitrogen reduction reaction; NO3 - yield rate up to 15.7 µg h-1 mg-1 cat. and FE up to 3.4 % in nitrogen oxidation reaction).

8.
Small ; 18(28): e2202582, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35708216

ABSTRACT

The exploitation of effective strategies to accelerate the Na+ diffusion kinetics and improve the structural stability in the electrode is extremely important for the development of high efficientcy sodium-ion batteries. Herein, Se vacancies and heterostructure engineering are utilized to improve the Na+ -storage performance of transition metal selenides anode prepared through a facile two-in-one route. The experimental results coupled with theoretical calculations reveal that the successful construction of the Se vacancies and heterostructure interfaces can effectively lower the Na+ diffusion barrier, accelerate the charge transfer efficiency, improve Na+ adsorption ability, and provide an abundance of active sites. Consequently, the batteries based on the constructed ZnSe/CoSe2 -CN anode manifest a high initial Coulombic efficiency (97.7%), remarkable specific capacities (547.1 mAh g-1 at 0.5 A g-1 ), superb rate capability (362.1 mAh g-1 at 20 A g-1 ), as well as ultrastable long-term stability (1000 cycles) with a satisfied specific capacity (535.6 mAh g-1 ) at 1 A g-1 . This work facilitates an in-depth understanding of the synergistic effect of vacancies and heterojunctions in improving the Na+ reaction kinetics, providing an effective strategy to the rational design of key materials for high efficiency rechargeable batteries.

9.
Ren Fail ; 44(1): 2056-2065, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36420656

ABSTRACT

BACKGROUND: In recent years, peroxisome proliferator-activated receptor γ (PPARγ) has been found to be closely associated with hypoxia renal disease. The aim of this study was to investigate the relationship between rosiglitazone and mitochondrial apoptosis in renal tissue and its associated mechanisms. METHODS: Twenty-four male Sprague-Dawley rats were randomly divided into three groups (n = 8 in each): normal control group, hypoxia injury group (equal volume of 0.9% saline), and PPARγ agonist group (Rosiglitazone, 10 mg/kg · d, intraperitoneally). The hypoxia injury group and PPARγ agonist group were placed in a hypoxia chamber and the simulated altitude was set at 7,000 m for 7 days. Blood and kidney samples were collected after 7 days. The quantitative real-time polymerase chain reaction and Western blot methods were used to determine the expression of PPARγ, nuclear factor kappa-B (NF-κB), B-cell lymphoma-2 (Bcl-2), and Bax. RESULTS: The results showed that compared with the normal control group, the renal tissue of rats after hypoxia was severely damaged, as shown by massive renal tubular epithelial cell degeneration and detachment, and renal tubular dilation. The NF-κB protein expression significantly increased, the Bcl-2 protein and mRNA expression significantly decreased, and Bax protein and mRNA expression significantly increased (p < .05 for all). Renal injury was much less severe in the PPARγ agonist group compared to the hypoxia injury group. CONCLUSIONS: Rosiglitazone can alleviate hypoxia renal injury, with the possible mechanism involving attenuation of apoptosis by inhibiting the activation of the NF-κB signaling pathway in a PPARγ-dependent manner and increasing Bcl-2 and decreasing Bax expression.


Subject(s)
PPAR gamma , Thiazolidinediones , Male , Rats , Animals , Rosiglitazone/pharmacology , PPAR gamma/metabolism , NF-kappa B/metabolism , bcl-2-Associated X Protein/metabolism , Thiazolidinediones/pharmacology , Thiazolidinediones/metabolism , Rats, Sprague-Dawley , Signal Transduction , Apoptosis , Epithelial Cells/metabolism , Hypoxia/complications , Hypoxia/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism , Hypoglycemic Agents , Kidney/metabolism , RNA, Messenger/metabolism
10.
Am J Drug Alcohol Abuse ; 47(5): 638-648, 2021 09 03.
Article in English | MEDLINE | ID: mdl-34325579

ABSTRACT

Background: Mind-body exercise is used for the rehabilitation of individuals with methamphetamine use disorder (MUD). Attention bias to substances is an important index of MUD. However, whether a mind-body exercise intervention can decrease attention bias is unclear.Objective: This study aimed to test the effect of a four-week Tai Chi (a Chinese traditional mind-body exercise) exercise program on the attention bias of individuals with MUD.Methods: Thirty-two men with MUD and without Tai Chi practice experience were recruited and randomly assigned to either a Tai Chi exercise group or a control group. The Tai Chi group received four-week Tai Chi training, while the control group engaged in daily exercise (including radio gymnastics and Jianxincao, two kinds of free-hand exercises). During a drug-related Stroop task, participants were instructed to respond to the color of the word ignoring the word type (drug-related or neutral words). The reaction time and d' (the index of sensitivity) were measured.Results: The participants showed attention bias to substance cues; the reaction time was slower for drug-related words than for neutral words (p < .05). After the Tai Chi intervention, the Tai Chi group showed a faster reaction time (ps < .05) and a smaller d' (ps < .05) than the baseline across all the word types. In contrast, the control group showed no differences (ps > .05).Conclusion: Four-week Tai Chi intervention reduced sensitivity and attentional bias to drug-related cues in individuals with MUD, suggesting that mind-body exercise might enhance recovery from MUD via attention control.


Subject(s)
Amphetamine-Related Disorders/therapy , Exercise Therapy/psychology , Tai Ji/psychology , Adult , Attentional Bias , Craving , Cues , Humans , Male , Methamphetamine , Middle Aged , Reaction Time , Stroop Test
11.
J Sci Food Agric ; 99(2): 703-710, 2019 Jan 30.
Article in English | MEDLINE | ID: mdl-29971802

ABSTRACT

BACKGROUND: Medicinal mushrooms contain biologically active substances that can be used as an immune-modulating agent in poultry. The present study aimed to investigate the effects of Flammulina velutipes mushroom waste (FVW) on performance, immune response and serum immunity in growing layer hens. RESULTS: No significant differences (P > 0.05) were observed with respect to average daily feed intake, body weight gain and feed conversion ratio among the experimental groups during the entire study period (1-70 days). Antibody titers against Newcastle disease and infectious bronchitis were higher (P < 0.05) in the FVW fed groups than in the control and antibiotic groups. On day 28, serum immunoglobulin (Ig)A and IgG were higher (P < 0.05) in the 6% FVW group than in the control and antibiotic fed groups. On day 70, serum IgA was higher (P < 0.05) in FVW fed groups than in the control group; IgG was higher (P < 0.05) in the FVW groups than in the control and antibiotic groups. However, IgM was higher (P < 0.05) in both the 4% and 6% FVW groups than in the control and antibiotic groups for both experimental periods. Serum cytokine interleukin (IL)-2 and tumor necrosis factor-α concentrations were significantly higher (P < 0.05) in both the 4% and 6% FVW grousp than in the control and antibiotic groups; IL-4 was significantly higher (P < 0.05) in the FVW groups than in the control group; and IL-6 was significantly higher (P < 0.05) in the 6% FVW group than in the control and antibiotic groups. CONCLUSION: FVW at the 6% level can be used as a potential phytogenic feed stuff in growing layer hen rations with respect to improving the immune response without affecting normal weight gain. © 2018 Society of Chemical Industry.


Subject(s)
Animal Feed/analysis , Chickens/growth & development , Dietary Supplements/analysis , Flammulina/chemistry , Immunity, Humoral , Poultry Diseases/immunology , Waste Products/analysis , Animals , Antibodies, Viral/immunology , Chickens/immunology , Chickens/metabolism , Chickens/virology , Coronavirus Infections/immunology , Coronavirus Infections/physiopathology , Coronavirus Infections/veterinary , Coronavirus Infections/virology , Female , Flammulina/metabolism , Infectious bronchitis virus/immunology , Infectious bronchitis virus/physiology , Newcastle Disease/immunology , Newcastle Disease/physiopathology , Newcastle Disease/virology , Newcastle disease virus/immunology , Newcastle disease virus/physiology , Poultry Diseases/physiopathology , Poultry Diseases/virology
12.
Small ; 14(32): e1801562, 2018 Aug.
Article in English | MEDLINE | ID: mdl-30003678

ABSTRACT

The use of free-standing carbon-based hybrids plays a crucial role to help fulfil ever-increasing energy storage demands, but is greatly hindered by the limited number of active sites for fast charge adsorption/desorption processes. Herein, an efficient strategy is demonstrated for making defect-rich bismuth sulfides in combination with surface nitrogen-doped carbon nanofibers (dr-Bi2 S3 /S-NCNF) as flexible free-standing electrodes for asymmetric supercapacitors. The dr-Bi2 S3 /S-NCNF composite exhibits superior electrochemical performances with an enhanced specific capacitance of 466 F g-1 at a discharge current density of 1 A g-1 . The high performance of dr-Bi2 S3 /S-NCNF electrodes originates from its hierarchical structure of nitrogen-doped carbon nanofibers with well-anchored defect-rich bismuth sulfides nanostructures. As modeled by density functional theory calculation, the dr-Bi2 S3 /S-NCNF electrodes exhibit a reduced OH- adsorption energy of -3.15 eV, compared with that (-3.06 eV) of defect-free bismuth sulfides/surface nitrogen-doped carbon nanofiber (df-Bi2 S3 /S-NCNF). An asymmetric supercapacitor is further fabricated by utilizing dr-Bi2 S3 /S-NCNF hybrid as the negative electrode and S-NCNF as the positive electrode. This composite exhibits a high energy density of 22.2 Wh kg-1 at a power density of 677.3 W kg-1 . This work demonstrates a feasible strategy to construct advanced metal sulfide-based free-standing electrodes by incorporating defect-rich structures using surface engineering principles.

13.
Small ; 13(7)2017 02.
Article in English | MEDLINE | ID: mdl-27918646

ABSTRACT

Molybdenum diselenide (MoSe2 ) has emerged as a promising electrocatalyst for hydrogen evolution reaction (HER). However, its properties are still confined due to the limited active sites and poor conductivity. Thus, it remains a great challenge to synergistically achieve structural and electronic modulations for MoSe2 -based HER catalysts because of the contradictory relationship between these two characteristics. Herein, bacterial cellulose-derived carbon nanofibers are used to assist the uniform growth of few-layered MoSe2 nanosheets, which effectively increase the active sites of MoSe2 for hydrogen atom adsorption. Meanwhile, carbonized bacterial cellulose (CBC) nanofibers provide a 3D network for electrolyte penetration into the inner space and accelerate electron transfer as well, thus leading to the dramatically increased HER activity. In acidic media, the CBC/MoSe2 hybrid catalyst exhibits fast hydrogen evolution kinetics with onset overpotential of 91 mV and Tafel slope of 55 mV dec-1 , which is much more outstanding than both bulk MoSe2 aggregates and CBC nanofibers. Furthermore, the fast HER kinetics are well supported by theoretical calculations of density-functional-theory analysis with a low activation barrier of 0.08 eV for H2 generation. Hence, this work highlights an efficient solution to develop high-performance HER catalysts by incorporating biotemplate materials, to simultaneously achieve increased active sites and conductivity.


Subject(s)
Electric Conductivity , Hydrogen/analysis , Imaging, Three-Dimensional , Molybdenum/chemistry , Nanofibers/chemistry , Selenium/chemistry , Bacteria/chemistry , Catalysis , Cellulose/chemistry , Electrons , Ions , Nanofibers/ultrastructure , Quantum Theory , X-Ray Diffraction
14.
Small ; 12(24): 3235-44, 2016 Jun.
Article in English | MEDLINE | ID: mdl-27135301

ABSTRACT

The development of biomass-based energy storage devices is an emerging trend to reduce the ever-increasing consumption of non-renewable resources. Here, nitrogen-doped carbonized bacterial cellulose (CBC-N) nanofibers are obtained by one-step carbonization of polyaniline coated bacterial cellulose (BC) nanofibers, which not only display excellent capacitive performance as the supercapacitor electrode, but also act as 3D bio-template for further deposition of ultrathin nickel-cobalt layered double hydroxide (Ni-Co LDH) nanosheets. The as-obtained CBC-N@LDH composite electrodes exhibit significantly enhanced specific capacitance (1949.5 F g(-1) at a discharge current density of 1 A g(-1) , based on active materials), high capacitance retention of 54.7% even at a high discharge current density of 10 A g(-1) and excellent cycling stability of 74.4% retention after 5000 cycles. Furthermore, asymmetric supercapacitors (ASCs) are constructed using CBC-N@LDH composites as positive electrode materials and CBC-N nanofibers as negative electrode materials. By virtue of the intrinsic pseudocapacitive characteristics of CBC-N@LDH composites and 3D nitrogen-doped carbon nanofiber networks, the developed ASC exhibits high energy density of 36.3 Wh kg(-1) at the power density of 800.2 W kg(-1) . Therefore, this work presents a novel protocol for the large-scale production of biomass-derived high-performance electrode materials in practical supercapacitor applications.


Subject(s)
Carbon/chemistry , Cobalt/chemistry , Hydroxides/chemistry , Nickel/chemistry , Nitrogen/chemistry , Biomass , Electrodes
15.
Chemistry ; 21(28): 10100-8, 2015 Jul 06.
Article in English | MEDLINE | ID: mdl-26061603

ABSTRACT

Increasing energy demands and worsening environmental issues have stimulated intense research on alternative energy storage and conversion systems including supercapacitors and fuel cells. Here, a rationally designed hierarchical structure of ZnCo2 O4 @NiCo2 O4 core-sheath nanowires synthesized through facile electrospinning combined with a simple co-precipitation method is proposed. The obtained core-sheath nanostructures consisting of mesoporous ZnCo2 O4 nanowires as the core and uniformly distributed ultrathin NiCo2 O4 nanosheets as the sheath, exhibit excellent electrochemical activity as bifunctional materials for supercapacitor electrodes and oxygen reduction reaction (ORR) catalysts. Compared with the single component of either ZnCo2 O4 nanowires or NiCo2 O4 nanosheets, the hierarchical ZnCo2 O4 @NiCo2 O4 core-sheath nanowires demonstrate higher specific capacitance of 1476 F g(-1) (1 A g(-1) ) and better rate capability of 942 F g(-1) (20 A g(-1) ), while maintaining 98.9 % capacity after 2000 cycles at 10 A g(-1) . Meanwhile, the ZnCo2 O4 @NiCo2 O4 core-sheath nanowires reveal comparable catalytic activity but superior stability and methanol tolerance over Pt/C as ORR catalyst. The impressive performance may originate from the unique hierarchical core-sheath structures that greatly facilitate enhanced reactivity, and faster ion and electron transfer.

16.
Angew Chem Int Ed Engl ; 53(20): 5054-8, 2014 May 12.
Article in English | MEDLINE | ID: mdl-24692329

ABSTRACT

Inspired by aphids, liquid marbles have been studied extensively and have found application as isolated microreactors, as micropumps, and in sensing. However, current liquid-marble-based sensing methodologies are limited to qualitative colorimetry-based detection. Herein we describe the fabrication of a plasmonic liquid marble as a substrate-less analytical platform which, when coupled with ultrasensitive SERS, enables simultaneous multiplex quantification and the identification of ultratrace analytes across separate phases. Our plasmonic liquid marble demonstrates excellent mechanical stability and is suitable for the quantitative examination of ultratrace analytes, with detection limits as low as 0.3 fmol, which corresponds to an analytical enhancement factor of 5×10(8). The results of our simultaneous detection scheme based on plasmonic liquid marbles and an aqueous-solid-organic interface quantitatively tally with those found for the individual detection of methylene blue and coumarin.


Subject(s)
Limit of Detection , Coumarins/analysis , Methylene Blue/analysis
17.
Front Pharmacol ; 15: 1405173, 2024.
Article in English | MEDLINE | ID: mdl-38939843

ABSTRACT

Background: Although caffeine generally offers benefits to human health, its impact on bone metabolism remains unclear. Aim and Methods: This study aimed to systematically evaluate the long-term effects of caffeine administration on osteoclasts, osteoblasts, and ovariectomy-induced postmenopausal osteoporosis (OP). Results: Our in vitro findings revealed that 3.125 and 12.5 µg/mL caffeine inhibited RANKL-mediated osteoclastogenesis in RAW 264.7 cells through the MAPK and NF-κB pathways, accompanied by the inactivation of nuclear translocation of nuclear factor NFATc1. Similarly, 3.125 and 12.5 µg/mL of caffeine modulated MC3T3-E1 osteogenesis via the AKT, MAPK, and NF-κB pathways. However, 50 µg/mL of caffeine promoted the phosphorylation of IκBα, P65, JNK, P38, and AKT, followed by the activation of NFATc1 and the inactivation of Runx2 and Osterix, ultimately disrupting the balance between osteoblastogenesis and osteoclastogenesis. In vivo studies showed that gavage with 55.44 mg/kg caffeine inhibited osteoclastogenesis, promoted osteogenesis, and ameliorated bone loss in ovariectomized mice. Conclusion: Conversely, long-term intake of high-dose caffeine (110.88 mg/kg) disrupted osteogenesis activity and promoted osteoclastogenesis, thereby disturbing bone homeostasis. Collectively, these findings suggest that a moderate caffeine intake (approximately 400 mg in humans) can regulate bone homeostasis by influencing both osteoclasts and osteoblasts. However, long-term high-dose caffeine consumption (approximately 800 mg in humans) could have detrimental effects on the skeletal system.

18.
Nanomicro Lett ; 16(1): 131, 2024 Feb 26.
Article in English | MEDLINE | ID: mdl-38409640

ABSTRACT

The demand for highly porous yet transparent aerogels with mechanical flexibility and solar-thermal dual-regulation for energy-saving windows is significant but challenging. Herein, a delaminated aerogel film (DAF) is fabricated through filtration-induced delaminated gelation and ambient drying. The delaminated gelation process involves the assembly of fluorinated cellulose nanofiber (FCNF) at the solid-liquid interface between the filter and the filtrate during filtration, resulting in the formation of lamellar FCNF hydrogels with strong intra-plane and weak interlayer hydrogen bonding. By exchanging the solvents from water to hexane, the hydrogen bonding in the FCNF hydrogel is further enhanced, enabling the formation of the DAF with intra-layer mesopores upon ambient drying. The resulting aerogel film is lightweight and ultra-flexible, which possesses desirable properties of high visible-light transmittance (91.0%), low thermal conductivity (33 mW m-1 K-1), and high atmospheric-window emissivity (90.1%). Furthermore, the DAF exhibits reduced surface energy and exceptional hydrophobicity due to the presence of fluorine-containing groups, enhancing its durability and UV resistance. Consequently, the DAF has demonstrated its potential as solar-thermal regulatory cooling window materials capable of simultaneously providing indoor lighting, thermal insulation, and daytime radiative cooling under direct sunlight. Significantly, the enclosed space protected by the DAF exhibits a temperature reduction of 2.6 °C compared to that shielded by conventional architectural glass.

19.
Adv Mater ; 36(26): e2400102, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38606728

ABSTRACT

Solar-thermal regulation concerning thermal insulation and solar modulation is pivotal for cooling textiles and smart buildings. Nevertheless, a contradiction arises in balancing the demand to prevent external heat infiltration with the efficient dissipation of excess heat from enclosed spaces. Here, a concentration-gradient polymerization strategy is presented for fabricating a gradient porous polymeric film comprising interconnected polymeric microspheres. This method involves establishing an electric field-driven gradient distribution of charged crosslinkers in the precursor solution, followed by subsequent polymerization and freeze-drying processes. The resulting porous film exhibits a significant porosity gradient along its thickness, leading to exceptional unidirectional thermal insulation capabilities with a thermal rectification factor of 21%. The gradient porous film, with its thermal rectification properties, effectively reconciles the conflicting demands of diverse thermal conductivity for cooling unheated and spontaneously heated enclosed spaces. Consequently, the gradient porous film demonstrates remarkable enhancements in solar-thermal management, achieving temperature reductions of 3.0 and 4.1 °C for unheated and spontaneously heated enclosed spaces, respectively, compared to uniform porous films. The developed gradient-structured porous film thus holds promise for the development of thermal-rectified materials tailored to regulate solar-thermal conditions within enclosed environments.

20.
ACS Omega ; 8(8): 7690-7698, 2023 Feb 28.
Article in English | MEDLINE | ID: mdl-36872994

ABSTRACT

Manganese dioxide and its derivatives are widely used as promising electrode materials for supercapacitors. To achieve the environmentally friendly, simple, and effective material synthesis requirements, the laser direct writing method is utilized to pyrolyze the MnCO3/carboxymethylcellulose (CMC) precursors to MnO2/carbonized CMC (LP-MnO2/CCMC) in a one-step and mask-free way successfully. Here, CMC is utilized as the combustion-supporting agent to promote the conversion of MnCO3 into MnO2. The selected materials have the following advantages: (1) MnCO3 is soluble and can be converted into MnO2 with the promotion of a combustion-supporting agent. (2) CMC is an eco-friendly and soluble carbonaceous material, which is widely used as the precursor and combustion-supporting agent; (3) the redundant part of the MnCO3/CMC precursor can be removed by deionized water, which is simple and convenient. The different mass ratios of MnCO3 and CMC-induced LP-MnO2/CCMC(R1) and LP-MnO2/CCMC(R1/5) composites are investigated in the electrochemical performance toward electrodes, respectively. The LP-MnO2/CCMC(R1/5)-based electrode showed the high specific capacitance of 74.2 F/g (at the current density of 0.1 A/g) and good electrical durability for 1000 times charging-discharging cycles. Simultaneously, the sandwich-like supercapacitor which was assembled by LP-MnO2/CCMC(R1/5) electrodes presents the maximum specific capacitance of 49.7 F/g at the current density of 0.1 A/g. Moreover, the LP-MnO2/CCMC(R1/5)-based energy supply system is used to light a light-emitting diode, which demonstrates the great potential of LP-MnO2/CCMC(R1/5)-based supercapacitors for power devices.

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