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2.
Curr Med Sci ; 2024 Aug 03.
Article in English | MEDLINE | ID: mdl-39096478

ABSTRACT

OBJECTIVE: The metabolic reprogramming of acute myeloid leukemia (AML) cells is a compensatory adaptation to meet energy requirements for rapid proliferation. This study aimed to examine the synergistic effects of glutamine deprivation and metformin exposure on AML cells. METHODS: SKM-1 cells (an AML cell line) were subjected to glutamine deprivation and/or treatment with metformin or bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl) ethyl sulfide (BPTES, a glutaminase inhibitor) or cytarabine. Cell viability was detected by Cell Counting Kit-8 (CCK-8) assay, and cell apoptosis and reactive oxygen species (ROS) by flow cytometry. Western blotting was conducted to examine the levels of apoptotic proteins, including cleaved caspase-3 and poly(ADP-ribose) polymerase (PARP). Moreover, the human long noncoding RNA (lncRNA) microarray was used to analyze gene expression after glutamine deprivation, and results were confirmed with quantitative RT-PCR (qRT-PCR). The expression of metallothionein 2A (MT2A) was suppressed using siRNA. Cell growth and apoptosis were further detected by CCK-8 assay and flow cytometry, respectively, in cells with MT2A knockdown. RESULTS: Glutamine deprivation or treatment with BPTES inhibited cell growth and induced apoptosis in SKM-1 cells. The lncRNA microarray result showed that the expression of MT family genes was significantly upregulated after glutamine deprivation. MT2A knockdown increased apoptosis, while proliferation was not affected in SKM-1 cells. In addition, metformin inhibited cell growth and induced apoptosis in SKM-1 cells. Both glutamine deprivation and metformin enhanced the sensitivity of SKM-1 cells to cytarabine. Furthermore, the combination of glutamine deprivation with metformin exhibited synergistic antileukemia effects on SKM-1 cells. CONCLUSION: Targeting glutamine metabolism in combination with metformin is a promising new therapeutic strategy for AML.

3.
Antonie Van Leeuwenhoek ; 117(1): 111, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-39103503

ABSTRACT

The strain designated NCCP-602T was isolated from tannery effluent, and displayed aerobic, gram-positive, rod-shaped cells that were characterized by oxidase negative, catalase positive, and non-motile features. The most favourable growth conditions were observed at a temperature of 30°C, pH 7.0, and NaCl concentration of 1% (w/v). It tolerated heavy metals at high concentrations of chromium (3600 ppm), copper (3300 ppm), cadmium (3000 ppm), arsenic (1200 ppm) and lead (1500 ppm). The results of phylogenetic analysis, derived from sequences of the 16S rRNA gene, indicated the position of strain NCCP-602T within genus Brevibacterium and showed that it was closely related to Brevibacterium ammoniilyticum JCM 17537T. Strain NCCP-602 T formed a robust branch that was clearly separate from closely related taxa. A comparison of 16S rRNA gene sequence similarity and dDDH values between the closely related type strains and strain NCCP-602T provided additional evidence supporting the classification of strain NCCP-602T as a distinct novel genospecies. The polar lipid profile included diphosphatidylglycerol, glycolipid, phospholipids and amino lipids. MK-7 and MK-8 were found as the respiratory quinones, while anteiso-C15:0, iso-C15:0, iso-C16:0, iso-C17:0, and anteiso-C17:0 were identified as the predominant cellular fatty acids (> 10%). Considering the convergence of phylogenetic, phenotypic, chemotaxonomic, and genotypic traits, it is suggested that strain NCCP-602 T be classified as a distinct species Brevibacterium metallidurans sp. nov. within genus Brevibacterium with type strain NCCP-602T (JCM 18882T = CGMCC1.62055T).


Subject(s)
Brevibacterium , Fatty Acids , Metals, Heavy , Phylogeny , RNA, Ribosomal, 16S , Brevibacterium/genetics , Brevibacterium/classification , Brevibacterium/isolation & purification , Brevibacterium/metabolism , Brevibacterium/physiology , RNA, Ribosomal, 16S/genetics , Metals, Heavy/metabolism , Pakistan , Fatty Acids/analysis , DNA, Bacterial/genetics , Bacterial Typing Techniques , Base Composition , Sequence Analysis, DNA , Phospholipids/analysis , Tanning , Genomics
4.
Psychiatry Investig ; 21(7): 772-781, 2024 Jul.
Article in English | MEDLINE | ID: mdl-39089703

ABSTRACT

OBJECTIVE: Patients with late life depression sometimes refuse to receive electroconvulsive therapy (ECT) owing to its adverse reactions. To alleviate patient's resistance, a novel ECT stimulation strategy named mixed-strategy ECT (msECT) was designed in which patients are administered conventional ECT during the first three sessions, followed by low energy stimulation during the subsequent sessions. However, whether low energy electrical stimulation in the subsequent stage of therapy affect its efficacy and reduce adverse reactions in patients with late life depression remains unknown. To explore differences between msECT and regular ECT(RECT) with respect to clinical efficacy and side effects. METHODS: This randomized, controlled trial was conducted from 2019 to 2021 on 60 patients with late life depression who were randomly assigned to two groups: RECT or msECT. A generalized estimating equation (GEE) was used to compare the two stimulation strategies regarding their efficacy and side effects on cognition. Chi-squared test was used to compare side effects in the two strategies. RESULTS: In the intent-to-treat group, the GEE model suggested no differences between-group difference in Hamilton Depression Rating Scale-17 score over time (Wald χ2=7.275, p=0.064), whereas the comparison of side effects in the two strategies favored msECT (Wald χ2=8.463, p=0.015) as fewer patients had adverse events during the second phase of treatment with msECT (χ2 =13.467, p=0.004). CONCLUSION: msECT presents its similar efficacy to RECT. msECT may have milder side effects on cognition.

5.
Endocr Connect ; 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39140811

ABSTRACT

Prenatal stress can lead to the programming of the neuroendocrine system in male offspring, disrupting the hypothalamic testicular axis and adversely affecting the reproductive health of male offspring. This study aimed to determine the long-term effects of prenatal stress on the KISS1 system in male offspring and the effects on reproductive function in male offspring. Sixteen pregnant females were divided into a prenatal control group (PC,n=8) and a prenatal stress group (PS,n=8). The PS group was modeled with chronic unpredictable mild stress (CUMS) from day 1 of gestation to full-term delivery. Differences between the two groups in various maternal parameters, including glucocorticoid secretion, litter size, and the effects of male offspring birth weight, the KISS1 system, and reproductive function, were determined. Male offspring of PS dams had lower birth weights compared to prenatal controls.KISS1 gene expression is reduced at birth and in adult PS offspring, and its receptor KISS1-R protein is similarly reduced in PS offspring at birth and adulthood. In adulthood, PS male offspring show significantly reduced sex hormone production, altered testicular morphology, reduced maturation of their supporting cells, and decreased expression of connexin 43 (CX43), leading to an altered sperm microenvironment and reduced sperm quality. In conclusion, prenatal stress leads to adverse changes in the KISS1 system in male offspring and decreased reproductive function.

6.
ACS Omega ; 9(31): 33833-33844, 2024 Aug 06.
Article in English | MEDLINE | ID: mdl-39130542

ABSTRACT

Liposome-based drug delivery systems have been widely used in drug and gene delivery. However, issues such as instability, immune clearance, and poor targeting have significantly limited their clinical utility. Consequently, there is an urgent need for innovative strategies to improve liposome performance. In this study, we explore the interaction mechanisms of hyaluronic acid (HA), a linear anionic polysaccharide composed of repeating disaccharide units of d-glucuronic acid and N-acetyl-d-glucosamine connected by alternating ß-1,3 and ß-1,4 glycosidic linkages, and its octanoylated derivates (OHA) with liposomes using extensive coarse-grained molecular dynamics simulations. The octyl moieties of OHA spontaneously inserted into the phospholipid bilayer of liposomes, leading to their effective coating onto the surface of liposome and enhancing their structural stability. Furthermore, encapsulating liposome with OHA neutralized their surface potential, interfering with the formation of a protein corona known to contribute to liposomal immune clearance. Importantly, the encapsulated OHA maintained its selectivity and therefore targeting ability for CD44, which is often overexpressed in tumor cells. These molecular-scale findings shed light on the interaction mechanisms between HA and liposomes and will be useful for the development of next-generation liposome-based drug delivery systems.

7.
Rev Sci Instrum ; 95(8)2024 Aug 01.
Article in English | MEDLINE | ID: mdl-39120445

ABSTRACT

State-of-the-art optical cavities are pivotal in pushing the envelope of laser frequency stability below 10-16. This is often achieved by extending the cavity length or cooling the system to cryogenic temperatures to reduce the thermal noise floor. In our study, we present a 30-cm-long cavity that operates at room temperature and is outfitted with crystalline coatings. The system has a predicted ultralow thermal noise floor of 4.4 × 10-17, comparable to what is observed in cryogenic silicon cavities. A 1397-nm laser is stabilized in this advanced cavity, and the stable frequency is then transferred to the clock transition in strontium optical lattice clocks via a frequency-doubling process. We have meticulously minimized and assessed the technical noise contributions through comparisons with an ultrastable reference laser that is locked to a commercially available 30-cm cavity. The frequency instability of the system is rigorously evaluated using a three-cornered-hat method. The results demonstrate that the laser frequency instability remains below 2 × 10-16 for averaging times ranging from 1 to 50 s. These findings underscore the significant potential of room-temperature cavities with crystalline coatings in high-precision metrology and pave the way for further improvements in optical lattice clocks.

8.
Nanomaterials (Basel) ; 14(15)2024 Jul 29.
Article in English | MEDLINE | ID: mdl-39120374

ABSTRACT

High-energy-density Li-CO2 batteries are promising candidates for large-capacity energy storage systems. However, the development of Li-CO2 batteries has been hindered by low cycle life and high overpotential. In this study, we propose a CO2-based thermoplastic polyurethane (CO2-based TPU) with CO2 adsorption properties and excellent self-healing performance to replace traditional polyvinylidene fluoride (PVDF) as the cathode binder. The CO2-based TPU enhances the interfacial concentration of CO2 at the cathode/electrolyte interfaces, effectively increasing the discharge voltage and lowering the charge voltage of Li-CO2 batteries. Moreover, the CO2 fixed by urethane groups (-NH-COO-) in the CO2-based TPU are difficult to shuttle to and corrode the Li anode, minimizing CO2 side reactions with lithium metal and improving the cycling performance of Li-CO2 batteries. In this work, Li-CO2 batteries with CO2-based TPU as the multifunctional binders exhibit stable cycling performance for 52 cycles at a current density of 0.2 A g-1, with a distinctly lower polarization voltage than PVDF bound Li-CO2 batteries.

9.
Materials (Basel) ; 17(15)2024 Aug 03.
Article in English | MEDLINE | ID: mdl-39124519

ABSTRACT

To address the challenges posed by the narrow oxidation decomposition potential window and the characteristic of low ionic conductivity at room temperature of solid polymer electrolytes (SPEs), carbon dioxide (CO2), epichlorohydrin (PO), caprolactone (CL), and phthalic anhydride (PA) were employed in synthesizing di-block copolymer PCL-b-PPC and PCL-b-PPCP. The carbonate and ester bonds in PPC and PCL provide high electrochemical stability, while the polyether segments in PPC contribute to the high ion conductivity. To further improve the ion conductivity, we added succinonitrile as a plasticizer to the copolymer and used the copolymer to assemble lithium metal batteries (LMBs) with LiFePO4 as the cathode. The LiFePO4/SPE/Li battery assembled with PCL-b-PPC electrolyte exhibited an initial discharge-specific capacity of 155.5 mAh·g-1 at 0.5 C and 60 °C. After 270 cycles, the discharge-specific capacity was 140.8 mAh·g-1, with a capacity retention of 90.5% and an average coulombic efficiency of 99%, exhibiting excellent electrochemical performance. The study establishes the design strategies of di-block polymer electrolytes and provides a new strategy for the application of LMBs.

10.
Cardiovasc Toxicol ; 2024 Aug 13.
Article in English | MEDLINE | ID: mdl-39136863

ABSTRACT

Previous studies have found a possible association between nickel and metabolic syndrome (MetS), but with conflicting results. No studies have determined whether nickel exposure increases the prevalence of MetS in the general U.S. population. Therefore, we used data from the National Health and Nutrition Examination Survey (NHANES) to assess the association between urinary nickel and MetS. Since urinary nickel levels were presented as a skewed distribution, they were normalized using a logarithmic transformation. Weighted multivariate logistic models, restricted cubic spline, threshold effect analysis, and subgroup analyses were used to examine the association between urinary nickel concentration and the risk of MetS and its components. Based on data from 1577 participants, individuals in the second, third, and fourth quartiles of urinary nickel had an adjusted OR for MetS of 1.42 (95% CI: 0.88, 2.28), 2.00 (95% CI: 1.22, 3.28), and 1.68 (95% CI: 1.05, 2.70), respectively, representing an inverted "L"-shaped nonlinear dose-response relationship with an inflection point at 0.2141 ng/L. Patients over the age of 40, males, less educated, and smokers are more susceptible to nickel exposure. In addition, there were significant associations between nickel and most components of the MetS, with the strongest to weakest correlations being high fasting glucose, reduced high-density lipoprotein, abdominal obesity, and elevated blood pressure; however, there was no significant correlation between nickel and hyperlipidemia. In conclusion, environmental nickel exposure increases the prevalence of MetS in U.S. adults, particularly in males over 40 years of age, those with less education, and smokers.

11.
Front Cell Dev Biol ; 12: 1406830, 2024.
Article in English | MEDLINE | ID: mdl-38946798

ABSTRACT

Background: Osteoarthritis (OA) knee patients have limited ability in physical function, or difficulties with physical tasks and activities may develop disability. This study aimed to observe the predictors of self-reported and performance-based physical function in patients with knee OA by analyzing the impacts of demographic, pathological, and muscle impairment factors. Methods: 135 knee OA patients participated in this study to complete self-reported questionnaires using Knee Injury and Osteoarthritis Outcome Score (KOOS). When measuring performance-based physical function, a 6-meter gait speed (6MGS) test was measured to evaluate their mobility, and a 5-time Sit-to-Stand test (5STS) was assessed to evaluate their balance. Pain intensity, knee extensor and flexor muscle strength, age, body mass index (BMI), durations of symptoms, and radiographic severity were also collected. Spearman correlation and stepwise multiple linear regression were used to explore the association and predictors in self-reported and performance-based physical function. Results: BMI and durations of symptoms did not indicate any significant correlation with either self-reported or performance-based physical function. Age is significantly negatively associated with 6MGS (r 2 = -0.383, p < 0.01), while knee extensor muscle strength has a moderate correlation with 5STS (r 2 = -0.528, p < 0.01). In the stepwise multiple linear regression models, pain intensity (ß = 0.712, p < 0.001), knee flexor muscle strength (ß = 0.112, p = 0.042) were significantly associated with self-reported physical function in daily activities and contributed to 55.0% of the variance in KOOS-PF score. Knee muscle strength, including knee extensor (5STS: ß = -0.428, p < 0.001) and flexor muscle strength (6MGS: ß = 0.367, p < 0.001), were the main predictors with performance-based physical function. Conclusion: Pain intensity was the leading risk factor of self-reported physical function, and knee flexor muscle strength contributed as well. The severity of knee OA, durations of symptoms and BMI did not contribute to physical function. However, knee extensor and flexor muscle strength were the main predictors of performance-based performance. Our results show that strengthening of weak knee muscles in both quadriceps and hamstring muscle strength should be considered a priory consideration in knee OA no matter if people are in the early or end-stage of knee OA.

12.
Nat Prod Res ; : 1-6, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38949790

ABSTRACT

Chemical investigation of the wild mushroom Entoloma clypeatum led to the isolation of one new A-nor B-aromatic C28 steroid (1), along with eight known compounds (2-9) from this mushroom. As far as we know, compound 1 represents an unprecedented type of natural product. The structure of the new compound was elucidated based on extensive spectroscopic data analysis of HR-ESI-MS, 1D, and 2D NMR, while the relative configuration was confirmed by NOESY correlations. In addition, the anti-inflammatory activity of compound 1 was evaluated against LPS induced NO production in RAW 264.7 macrophages. Compound 1 exhibited a moderate anti-inflammatory activity with an IC50 value of 24.56 ± 1.72 µM.

13.
World J Clin Cases ; 12(18): 3360-3367, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38983425

ABSTRACT

BACKGROUND: Although chemotherapy is effective for treating advanced gastric carcinoma (aGC), it may lead to an adverse prognosis. Establishing a highly effective and low-toxicity chemotherapy regimen is necessary for improving efficacy and outcomes in aGC patients. AIM: To determine the efficacy and safety of cetuximab (CET) combined with the FOLFOX4 regimen (infusional fluorouracil, folinic acid, and oxaliplatin) as first-line therapy for patients with aGC, who received evidence-based care (EBC). METHODS: A total of 117 aGC patients who received EBC from March 2019 to March 2022 were enrolled. Of these, 60 in the research group (RG) received CET + FOLFOX4 as first-line therapy, whereas 57 in the control group (CG) received FOLFOX4. The efficacy [clinical response rate (RR) and disease control rate (DCR)], safety (liver and kidney dysfunction, leukopenia, thrombocytopenia, rash, and diarrhea), serum tumor marker expression [STMs; carbohydrate antigen (CA) 19-9, CA72-4, and carcinoembryonic antigen (CEA)], inflammatory indicators [interleukin (IL)-2 and IL-10], and quality of life (QOL) of the two groups were compared. RESULTS: A markedly higher RR and DCR were observed in the RG compared with the CG, with an equivalent safety profile between the two groups. RG exhibited notably reduced CA19-9, CA72-4, CEA, and IL-2 levels following treatment, which were lower than the pre-treatment levels and those in the CG. Post-treatment IL-10 was statistically increased in RG, higher than the pre-treatment level and the CG. Moreover, a significantly improved QOL was evident in the RG. CONCLUSION: The CET + FOLFOX4 regimen is highly effective as first-line treatment for aGC patients receiving EBC. It facilitates the suppression of STMs, ameliorates the serum inflammatory microenvironment, and enhances QOL, without increased adverse drug effects.

14.
World J Gastrointest Oncol ; 16(6): 2842-2861, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38994129

ABSTRACT

BACKGROUND: Gastrointestinal neoplasm (GN) significantly impact the global cancer burden and mortality, necessitating early detection and treatment. Understanding the evolution and current state of research in this field is vital. AIM: To conducts a comprehensive bibliometric analysis of publications from 1984 to 2022 to elucidate the trends and hotspots in the GN risk assessment research, focusing on key contributors, institutions, and thematic evolution. METHODS: This study conducted a bibliometric analysis of data from the Web of Science Core Collection database using the "bibliometrix" R package, VOSviewer, and CiteSpace. The analysis focused on the distribution of publications, contributions by institutions and countries, and trends in keywords. The methods included data synthesis, network analysis, and visualization of international collaboration networks. RESULTS: This analysis of 1371 articles on GN risk assessment revealed a notable evolution in terms of research focus and collaboration. It highlights the United States' critical role in advancing this field, with significant contributions from institutions such as Brigham and Women's Hospital and the National Cancer Institute. The last five years, substantial advancements have been made, representing nearly 45% of the examined literature. Publication rates have dramatically increased, from 20 articles in 2002 to 112 in 2022, reflecting intensified research efforts. This study underscores a growing trend toward interdisciplinary and international collaboration, with the Journal of Clinical Oncology standing out as a key publication outlet. This shift toward more comprehensive and collaborative research methods marks a significant step in addressing GN risks. CONCLUSION: This study underscores advancements in GN risk assessment through genetic analyses and machine learning and reveals significant geographical disparities in research emphasis. This calls for enhanced global collaboration and integration of artificial intelligence to improve cancer prevention and treatment accuracy, ultimately enhancing worldwide patient care.

15.
Phys Rev Lett ; 132(26): 263801, 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38996306

ABSTRACT

Theoretical and experimental studies suggest that both Hermitian and non-Hermitian quasicrystals show localization due to the fractal spectrum and to the transition to diffusive bands via exceptional points, respectively. Here, we present an experimental study of a dodecagonal photonic quasicrystal based on electromagnetically induced transparency in a Rb vapor cell. First, we observe the suppression of the wave packet expansion in the Hermitian case. We then discover a new regime, where increasing the non-Hermiticity leads to delocalization, demonstrating that the behavior in non-Hermitian quasicrystals is richer than previously thought.

16.
Front Nephrol ; 4: 1406655, 2024.
Article in English | MEDLINE | ID: mdl-39006160

ABSTRACT

Anticoagulant related nephropathy (ARN) is the result of glomerular hemorrhage in patients on systemic anticoagulation therapy or underlying coagulopathy. Red blood cells (RBC) that passed through the glomerular filtration barrier form RBC casts in the tubules, increase oxidative stress and result in acute tubular necrosis (ATN). The mechanisms of ARN still not completely discovered. Plasminogen activator inhibitor-1 (PAI-1) plays a significant role in the maintenance of coagulation homeostasis. We developed an animal model to study ARN in 5/6 nephrectomy (5/6NE) rats. The aim of this study was to elucidate the role of PAI-1 in the ARN pathogenesis. 5/6NE rats were treated per os with warfarin (0.75 mg/kg/day) or dabigatran (150 mg/kg/day) alone or in combination with PAI-1 antagonist TM5441 (2.5, 5.0 and 10 mg/kg/day). TM5441 in a dose dependent manner ameliorated anticoagulant-induced increase in serum creatinine in 5/6NE rats. Anticoagulant-associated increase in hematuria was no affected by TM5441. The levels of reactive oxygen species (ROS) in the kidneys were in a dose-dependent manner decreased in 5/6NE rats treated with an anticoagulant and TM5441. Our data demonstrates that PAI-1 may reduce ARN by decreasing ROS in the kidneys. Glomerular hemorrhage is not affected by anti-PAI-1 treatment. These findings indicate that while symptoms of ARN can be reduced by PAI-1 inhibition, the main pathogenesis of ARN - glomerular hemorrhage - cannot be prevented.

17.
Materials (Basel) ; 17(13)2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38998191

ABSTRACT

Fatigue cracking is one of the primary distresses of asphalt pavements, which significantly affects the asphalt pavement performance. The fatigue behavior of the asphalt mixture observed in the laboratory test can vary depending on the type of fatigue test and the dimension and shape of the test specimen. The variations can make it difficult to accurately evaluate the fatigue properties of the field asphalt concrete. Accordingly, this study proposed a reliable method to evaluate the fatigue behavior of the asphalt field cores based on discrete element modeling (DEM). The mesoscopic geometric model was built using discrete element software PFC (Particle Flow Code) and CT scan images of the asphalt field cores. The virtual fatigue test was simulated in accordance with the semi-circular bending (SCB) test. The mesoscopic parameters of the contacting model in the virtual test were determined through the uniaxial compression dynamic modulus test and SCB test. Based on the virtual SCB test, the displacement, contact forces, and crack growth were analyzed. The test results show that the fatigue life simulated in the virtual test was consistent with that of the SCB fatigue test. The fatigue cracks in the asphalt mixture were observed in three stages, i.e., crack initiation, crack propagation, and failure. It was found that the crack propagation stage consumes a significant portion of the fatigue life since the tensile contact forces mainly increase in this stage.

18.
Materials (Basel) ; 17(13)2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38998236

ABSTRACT

The binder ratio in a commercial lithium-ion battery is very low, but it is one of the key materials affecting the battery's performance. In this paper, polycarbonate-based polymers with liner or chain extension structures are proposed as binders. Then, dry LiFePO4 (LFP) electrodes with these binders are prepared using the solvent-free method. Polycarbonate-based polymers have a high tensile strength and a satisfactory bonding strength, and the rich polar carbonate groups provide highly ionic conductivity as binders. The batteries with poly (propylene carbonate)-plus (PPC-P) as binders were shown to have a long cycle life (350 cycles under 1 C, 89% of capacity retention). The preparation of dry electrodes using polycarbonate-based polymers can avoid the use of solvents and shorten the process of preparing electrodes. It can also greatly reduce the manufacturing cost of batteries and effectively use industrial waste gas dioxide oxidation. Most importantly, a battery material with this kind of polycarbonate polymer as a binder is easily recycled by simply heating after the battery is discarded. This paper provides a new idea for the industrialization and development of a novel binder.

19.
Nanomaterials (Basel) ; 14(13)2024 Jun 29.
Article in English | MEDLINE | ID: mdl-38998725

ABSTRACT

Poly(propylene carbonate-co-phthalate) (PPC-P) is an amorphous copolymer of aliphatic polycarbonate and aromatic polyester; it possesses good biodegradability, superior mechanical performances, high thermal properties, and excellent affinity with CO2. Hence, we fabricate PPC-P foams in an autoclave by using subcritical CO2 as a physical blowing agent. Both saturation pressure and foaming temperature affect the foaming behaviors of PPC-P, including CO2 adsorption and desorption performance, foaming ratio, cell size, porosity, cell density, and nucleation density, which are investigated in this research. Moreover, the low-cost PPC-P/nano-CaCO3 and PPC-P/starch composites are prepared and foamed using the same procedure. The obtained PPC-P-based foams show ultra-high expansion ratio and refined microcellular structures simultaneously. Besides, nano-CaCO3 can effectively improve PPC-P's rheological properties and foamability. In addition, the introduction of starch into PPC-P can lead to a large number of open cells. Beyond all doubt, this work can certainly provide both a kind of new biodegradable PPC-P-based foam materials and an economic methodology to make biodegradable plastic foams. These foams are potentially applicable in the packaging, transportation, and food industry.

20.
ERJ Open Res ; 10(4)2024 Jul.
Article in English | MEDLINE | ID: mdl-38957167

ABSTRACT

Background: Few studies have compared the associations between long-term exposures to particulate matters (aerodynamic diameter ≤1, ≤2.5 and ≤10 µm: PM1, PM2.5 and PM10, respectively) and asthma and asthma-related respiratory symptoms. The objective of the present study was to compare the strength of the aforementioned associations in middle-aged and elderly adults. Methods: We calculated the mean 722-day personal exposure estimates of PM1, PM2.5 and PM10 at 1 km×1 km spatial resolution between 2013 and 2019 at individual levels from China High Air Pollutants (CHAP) datasets. Using logistic regression models, we presented the associations as odds ratios and 95% confidence intervals, for each interquartile range (IQR) increase in PM1/PM2.5/PM10 concentration. Asthma denoted a self-reported history of physician-diagnosed asthma or wheezing in the preceding 12 months. Results: We included 7371 participants in COPD surveillance from Guangdong, China. Each IQR increase in PM1, PM2.5 and PM10 was associated with a greater odds (OR (95% CI)) of asthma (PM1: 1.22 (1.02-1.45); PM2.5: 1.24 (1.04-1.48); PM10: 1.30 (1.07-1.57)), wheeze (PM1: 1.27 (1.11-1.44); PM2.5: 1.30 (1.14-1.48); PM10: 1.34 (1.17-1.55)), persistent cough (PM1: 1.33 (1.06-1.66); PM2.5: 1.36 (1.09-1.71); PM10: 1.31 (1.02-1.68)) and dyspnoea (PM1: 2.10 (1.84-2.41); PM2.5: 2.17 (1.90-2.48); PM10: 2.29 (1.96-2.66)). Sensitivity analysis results were robust after excluding individuals with a family history of allergy. Associations of PM1, PM2.5 and PM10 with asthma and asthma-related respiratory symptoms were slightly stronger in males. Conclusion: Long-term exposure to PM is associated with increased risks of asthma and asthma-related respiratory symptoms.

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