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1.
Polymers (Basel) ; 16(9)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38732751

RESUMO

Cellulose is used widely in antimicrobial packaging due to its abundance in nature, biodegradability, renewability, non-toxicity, and low cost. However, how efficiently and rapidly it imparts high antimicrobial activity to cellulose-based packaging materials remains a challenge. In this work, Ag NPs were deposited on the surface of carboxymethyl cellulose/starch/N'N Methylenebisacrylamide film using ultrasonic radiation. Morphology and structure analysis of as-prepared films were conducted, and the antibacterial effects under different ultrasonic times and reductant contents were investigated. These results showed that Ag NPs were distributed uniformly on the film surface under an ultrasonic time of 45 min. The size of Ag NPs changes as the reducing agent content decreases. The composite film demonstrated a slightly better antibacterial effect against E. coli than against S. aureus. Therefore, this work can provide valuable insights for the research on antimicrobial packaging.

2.
Aging Cell ; : e14181, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689463

RESUMO

Postmenopausal osteoporosis is a prevalent metabolic bone disorder characterized by a decrease in bone mineral density and deterioration of bone microstructure. Despite the high prevalence of this disease, no effective treatment for osteoporosis has been developed. Exercise has long been considered a potent anabolic factor that promotes bone mass via upregulation of myokines secreted by skeletal muscle, exerting long-term osteoprotective effects and few side effects. Irisin was recently identified as a novel myokine that is significantly upregulated by exercise and could increase bone mass. However, the mechanisms underlying exercise-induced muscle-bone crosstalk remain unclear. Here, we identified that polyunsaturated fatty acids (arachidonic acid and docosahexaenoic acid) are increased in skeletal muscles following a 10-week treadmill exercise programme, which then promotes the expression and release of FNDC5/irisin. In osteoblasts, irisin binds directly to Cav1, which recruits and interacts with AMP-activated protein kinase α (AMPKα) to activate the AMPK pathway. Nrf2 is the downstream target of the AMPK pathway and increases the transcription of HMOX1 and Fpn. HMOX1 is involved in regulating the cell cycle and promotes the proliferation of osteoblasts. Moreover, upregulation of Fpn in osteoblasts enhanced iron removal, thereby suppressing ferroptosis in osteoblasts. Additionally, we confirmed that myotube-derived exosomes are involved in the transportation of irisin and enter osteoblasts through caveolae-mediated endocytosis. In conclusion, our findings highlight the crucial role of irisin, present in myotube-derived exosomes, as a crucial regulator of exercise-induced protective effects on bone, which provides novel insights into the mechanisms underlying exercise-dependent treatment of osteoporosis.

3.
Biomed Pharmacother ; 175: 116615, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38663101

RESUMO

Estrogens play a critical role in the initiation and progression of breast cancer. Estrogen receptor (ER)α, ERß, and G protein-coupled estrogen receptor are the primary receptors for estrogen in breast cancer. These receptors are mainly activated by binding with estrogens. The crosstalk between ERs and membrane growth factor receptors creates additional pathways that amplify the effects of their ligands and promote tumor growth. This crosstalk may cause endocrine therapy resistance in ERα-positive breast cancer. Furthermore, this may explain the resistance to anti-human epidermal growth factor receptor-2 (HER2) treatment in ERα-/HER2-positive breast cancer and chemotherapy resistance in triple-negative breast cancer. Accordingly, it is necessary to understand the complex crosstalk between ERs and growth factor receptors. In this review, we delineate the crosstalk between ERs and membrane growth factor receptors in breast cancer. Moreover, this review highlights the current progress in clinical treatment and discusses how pharmaceuticals target the crosstalk. Lastly, we discuss the current challenges and propose potential solutions regarding the implications of targeting crosstalk via pharmacological inhibition. Overall, the present review provides a landscape of the crosstalk between ERs and membrane growth factor receptors in breast cancer, along with valuable insights for future studies and clinical treatments using a chemotherapy-sparing regimen to improve patient quality of life.

4.
J Environ Manage ; 359: 120782, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38669884

RESUMO

Capturing CO2 using clamshell/eggshell-derived CaO adsorbent can not only reduce carbon emissions but also alleviate the impact of trash on the environment. However, organic acid was usually used, high-temperature calcination was often performed, and CO2 was inevitably released during preparing CaO adsorbents from shell wastes. In this work, CaO-based CO2 adsorbent was greenly prepared by calcium-induced hydrogenation of clamshell and eggshell wastes in one pot at room/moderate temperature. CO2 adsorption experiments were performed in a thermogravimetric analyzer (TGA). The adsorption performance of the adsorbents obtained from the mechanochemical reaction (BM-C/E-CaO) was superior to that of the adsorbents obtained from the thermochemical reaction (Cal-C/E-CaO). The CO2 adsorption capacity of BM-C-CaO at 650 °C is up to 36.82 wt%, but the adsorption decay rate of the sample after 20 carbonation/calcination cycles is only 30.17%. This study offers an alternative energy-saving method for greenly preparing CaO-based adsorbent from shell wastes.

5.
ACS Chem Biol ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38662199

RESUMO

Targeted protein degradation is becoming more and more important in the field of drug development. Compared with proteasomal-based degraders, lysosomal-based degraders have a broader target spectrum of targets, which have been demonstrated to have great potential, especially in degrading undruggable proteins. Recently, we developed a programmable and facile screening PROTAC development platform based on peptide self-assembly termed split-and-mix PROTAC (SM-PROTAC). In this study, we applied this technology for the development of lysosome-based degraders, named a split-and-mix chaperone-mediated autophagy-based degrader (SM-CMAD). We successfully demonstrated SM-CMAD as a universal platform by degrading several targets, including ERα, AR, MEK1/2, and BCR-ABL. Different from other lysosomal-based degraders, SM-CMAD was capable of facile screening with programmable ligand ratios. We believe that our work will promote the development of other multifunctional molecules and clinical translation for lysosomal-based degraders.

6.
Health Commun ; : 1-11, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38629476

RESUMO

The impact of celebrities on public awareness in health communication has been proved to be significant, making it a possible approach for risk communication during public health emergencies. In the early stages of COVID-19, some Chinese medical experts engaged with the public and became "celebrity scientists." It provides representative cases for studying celebrity-based risk communication approaches. With Dr. Wenhong Zhang as the primary case, this research investigates the construction process of celebrity scientists. Through semantic network analysis (SemNA) and other complementary methods, this study examines Dr. Zhang's articles (n1 = 45), relevant news reports (n2 = 360), and public tweets (n3 = 12,933), in order to identify the main agendas of media, public and expert during the construction process of celebrity scientists, as well as their similarities and differences. The results reveal three categories in the narratives around the celebrity scientist, highlighting unbalanced focuses and preferences. Notably, the agendas of celebrity scientists, media outlets and the general public are more alike than different, and tend to converge over time. The simultaneous resonance of the media and public is also crucial in the construction of celebrity scientists, as well as specific incidents or turning points. These findings shed light on the application of celebrity-based risk communication approach in emergencies, providing guidance and discussion points for health messaging strategies as well.

7.
Food Chem ; 451: 139477, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38678664

RESUMO

In this study, a combination of whey protein (hydrophilic coating) and polydopamine (crosslinking agent) was used to improve the stability and functionality of quercetin-loaded zein nanoparticles. There are two key benefits of the core-shell nanoparticles formed. First, the ability of the polydopamine to bind to both zein and whey protein facilitates the formation of a stable core-shell structure, thereby protecting quercetin from any pro-oxidants in the aqueous surroundings. Second, neutral and hydrophilic whey proteins were used for the surface coating of the nanoparticles to further enhance the sustained and slow release of quercetin, facilitating its sustained release into the body at a slow and steady rate. The results of this study will promote the innovative development of precise nutritional delivery systems for zein and provide a theoretical basis for the design and development of dietary supplements based on hydrophobic food nutrient molecules.

8.
Int J Biol Macromol ; 268(Pt 2): 131786, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38657927

RESUMO

This study investigated impact of high-density lipoprotein (HDL) on thermal aggregation and gelling behavior of myosin in relation to varied pHs. Results revealed that HDL modified myosin structure before and after heating, with distinct effects observed at varied pH. Under pH 5.0, both myosin and HDL-MS exhibited larger aggregates and altered microstructure; at pH 7.0 and 9.0, HDL inhibited myosin aggregation, resulting in enhanced solubility, reduced turbidity and particle size. Comparative analysis of surface hydrophobicity, free sulfhydryl groups and secondary structure highlighted distinct thermal aggregation behavior between MS and HDL-MS, with the latter showing inhibitory effects under neutral or alkaline conditions. Gelation behavior was enhanced at pH 7.0 with maximum strength, hardness, water-holding capacity and rheological properties. Under acidic pH, excessive protein aggregation resulted in increased whiteness and rough microstructure with granular aggregates. Under alkaline pH, gel network structure was weaker, possibly due to higher thermal stability of protein molecules. Scanning electron microscopy revealed expanded HDL protein particles at pH 7.0, accounting for decreased gel strength and altered rheological properties compared with myosin gel. Overall, the results indicated a positive role of HDL at varied pH in regulating thermal aggregation of myosin and further impacting heat-induced gel characteristics.

9.
Polymers (Basel) ; 16(8)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38674986

RESUMO

The recycling of plastic packaging wastes helps to alleviate the problems of white pollution and resource shortage. It is very necessary to develop high-value conversion technologies for plastic packaging wastes. To our knowledge, carbon materials with excellent properties have been widely used in energy storage, adsorption, water treatment, aerospace and functional packaging, and so on. Waste plastic packaging and biomass materials are excellent precursor materials of carbon materials due to their rich sources and high carbon content. Thus, the conversion from waste plastic packaging and biomass materials to carbon materials attracts much attention. However, closely related reviews are lacking up to now. In this work, the pyrolysis routes of the pyrolysis of plastic packaging wastes and biomass materials for conversion to high-value carbons and the influence factors were analyzed. Additionally, the applications of these obtained carbons were summarized. Furthermore, the limitations of the current pyrolysis technology are put forward and the research prospects are forecasted. Therefore, this review can provide a useful reference and guide for the research on the pyrolysis of plastic packaging wastes and biomass materials and the conversion to high-value carbon.

10.
Development ; 151(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38602507

RESUMO

CFAP58 is a testis-enriched gene that plays an important role in the sperm flagellogenesis of humans and mice. However, the effect of CFAP58 on bull semen quality and the underlying molecular mechanisms involved in spermatogenesis remain unknown. Here, we identified two single-nucleotide polymorphisms (rs110610797, A>G and rs133760846, G>T) and one indel (g.-1811_ g.-1810 ins147bp) in the promoter of CFAP58 that were significantly associated with semen quality of bulls, including sperm deformity rate and ejaculate volume. Moreover, by generating gene knockout mice, we found for the first time that the loss of Cfap58 not only causes severe defects in the sperm tail, but also affects the manchette structure, resulting in abnormal sperm head shaping. Cfap58 deficiency causes an increase in spermatozoa apoptosis. Further experiments confirmed that CFAP58 interacts with IFT88 and CCDC42. Moreover, it may be a transported cargo protein that plays a role in stabilizing other cargo proteins, such as CCDC42, in the intra-manchette transport/intra-flagellar transport pathway. Collectively, our findings reveal that CFAP58 is required for spermatogenesis and provide genetic markers for evaluating semen quality in cattle.


Assuntos
Análise do Sêmen , Sêmen , Humanos , Bovinos , Masculino , Animais , Camundongos , Cabeça do Espermatozoide , Espermatozoides , Camundongos Knockout
11.
Food Chem ; 449: 139232, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38581794

RESUMO

To effectively inhibit the retrogradation of staple foods, the effects of maltotetraose-forming amylase(G4-amylase) on the short and long-term retrogradation of different staple starches such as rice starch (RS), wheat starch (WS), potato starch (PS) were studied. The results indicated that G4-amylase decreased the content of amylose. Amylose contents (21.09%) of WSG4 were higher than that (14.82%) of RSG4 and (13.13%) of PSG4. WS had the most obvious change in the chain length distribution of amylopectin. A chains decreased by 18.99% and the B1 chains decreased by 12.08% after G4-amylase treatment. Compared to RS (662 cP) and WS (693 cP), the setback viscosity of RSG4 (338 cP) and WSG4 (385 cP) decreased. Compared to RS (0.41), WS (0.45), and PS (0.51), the long-term retrogradation rate of RSG4 (0.33), WSG4 (0.31), and PSG4 (0.38) significantly reduced. It indicated that G4-amylase significantly inhibited the long-term retrogradation of WS, followed by RS and PS.


Assuntos
Amilases , Maltose/análogos & derivados , Oryza , Solanum tuberosum , Amido , Triticum , Amido/química , Amilases/química , Amilases/metabolismo , Triticum/química , Viscosidade , Solanum tuberosum/química , Oryza/química , Amilose/química , Amilose/análise , Maltose/química , Biocatálise
12.
Am J Clin Nutr ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38677523

RESUMO

BACKGROUND: It is unclear whether salivary iodine concentration (SIC) can assess iodine status in females from different water iodine regions. OBJECTIVES: Through a cross-sectional study, we explored the feasibility of SIC as a biomarker to assess iodine status in females and develop optimal cutoff values. METHODS: A total of 1991 females were analyzed in this cross-sectional study from the coastal iodine-deficient areas (CIDAs), inland iodine-deficient areas (IIDAs), iodine-adequate areas (IAAs), iodine-excess areas (IEAs), and iodine extra-high areas (IEHAs). SIC, spot urine iodine concentration (SUIC), and daily total iodine intake (TII) were assessed, and ultrasonography was performed in all subjects. RESULTS: There was a positive correlation between SIC and SUIC (r = 0.67; 95% CI: 0.64, 0.69; P < 0.001), and TII (r = 0.47; 95% CI: 0.43, 0.50; P < 0.001). The prevalence of thyroid nodules (TN) showed an upward trend with SIC increasing (Z = -2.83; P-trend = 0.005). The area under the receiver-operating characteristic (ROC) curve for SIC to assess iodine deficiency was 0.62 (95% CI: 0.60, 0.65; P < 0.001) and 0.75 (95% CI: 0.73, 0.77; P < 0.001) for iodine excess. The cutoff values were as follows: SIC < 93.32 µg/L, iodine deficiency; 93.32-224.60 µg/L, iodine adequacy; and >224.60 µg/L, iodine excess. When SIC > 224.60 µg/L, the odds ratio (OR) for UIC > 300 µg/L, excessive TII, and the prevalence of TN were 6.44, 3.68, and 1.27 (95% CI: 4.98, 8.31; 2.83, 4.79; and 1.02, 1.56, respectively; P < 0.05); when SIC < 93.32 µg/L, the OR for UIC < 100 µg/L and insufficient TII were 2.34 and 1.94 (95% CI: 1.73, 3.14 and 1.33, 2.83, respectively; P < 0.05). CONCLUSIONS: Using SIC as a biomarker, females in CIDA exhibited mild iodine deficiency, those in IIDA and IAA demonstrated moderate iodine deficiency, and those in IEA and IEHA exhibited an excess of iodine, consistent with SUIC to assess iodine status. SIC can be used as a good biomarker to evaluate the iodine status in population.

13.
Oncogene ; 43(18): 1386-1396, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38467852

RESUMO

Clear cell renal cell carcinoma (ccRCC) presents a unique profile characterized by high levels of angiogenesis and robust vascularization. Understanding the underlying mechanisms driving this heterogeneity is essential for developing effective therapeutic strategies. This study revealed that ubiquitin B (UBB) is downregulated in ccRCC, which adversely affects the survival of ccRCC patients. UBB exerts regulatory control over vascular endothelial growth factor A (VEGFA) by directly interacting with specificity protein 1 (SP1), consequently exerting significant influence on angiogenic processes. Subsequently, we validated that DNA methyltransferase 3 alpha (DNMT3A) is located in the promoter of UBB to epigenetically inhibit UBB transcription. Additionally, we found that an unharmonious UBB/VEGFA ratio mediates pazopanib resistance in ccRCC. These findings underscore the critical involvement of UBB in antiangiogenic therapy and unveil a novel therapeutic strategy for ccRCC.


Assuntos
Carcinoma de Células Renais , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais , Neovascularização Patológica , Fator de Transcrição Sp1 , Fator A de Crescimento do Endotélio Vascular , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/irrigação sanguínea , Carcinoma de Células Renais/tratamento farmacológico , Humanos , Neoplasias Renais/patologia , Neoplasias Renais/genética , Neoplasias Renais/irrigação sanguínea , Neoplasias Renais/metabolismo , Neoplasias Renais/tratamento farmacológico , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp1/genética , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Linhagem Celular Tumoral , Animais , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Indazóis/farmacologia , Indazóis/uso terapêutico , DNA Metiltransferase 3A/metabolismo , Sulfonamidas/farmacologia , Camundongos , Ubiquitina/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regiões Promotoras Genéticas , Feminino , Masculino , Angiogênese
14.
J Colloid Interface Sci ; 663: 947-960, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38447408

RESUMO

Regulating product selectivity in photocatalytic CO2 reduction to enhance the yield of valuable hydrocarbons remains a formidable challenge because of the diversity of reduction products and the competitive reduction of H2O. Herein, ultrathin Bi2O3/ Co-doped SrBi4Ti4O15 S-scheme photocatalysts (Co-BS) were synthesized using a hydrothermal method. The Bi2O3/Co-doped SrBi4Ti4O15 photocatalyst exhibited significantly higher selectivity for CH4 (62.3 µmolg-1) and CH3OH (54.1 µmolg-1) in CO2 reduction compared with pure SrBi4Ti4O15 (27.2 and 0.8 µmolg-1) and the Bi2O3/SrBi4Ti4O15 S-scheme without Co (30.2 and 0 µmolg-1). The experimental results demonstrated that the inclusion of Co into SrBi4Ti4O15 expanded the range of light absorption and generated an internal electric field between Co-doped SrBi4Ti4O15 and Bi2O3. Density functional theory calculations and other experimental findings confirmed the formation of a new doping energy level in the Bi2O3/SrBi4Ti4O15 S-scheme heterojunction after Co doping. The valence band electrons of Bi2O3/SrBi4Ti4O15 transitioned to the Co-doped level because of the interconversion between Co3+ and Co2+ under the action of the internal electric field. Furthermore, the corresponding characterizations revealed that the adsorption and electron transfer rates of the surface active sites were accelerated after Co doping, enhancing electron involvement in the photocatalytic reaction process. This study presented a metal-doped S-scheme heterojunction approach for CO2 reduction to produce high-value products, enhancing the conversion of solar energy into energy resources.

15.
Front Cell Dev Biol ; 12: 1338448, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38476263

RESUMO

Triple-negative breast cancer (TNBC) is a biologically and clinically heterogeneous disease. The G protein-coupled estrogen receptor (GPER) plays a crucial role in mediating the effect of estrogen and estrogen-like compounds in TNBC cells. Compared with other subtypes, GPER has a higher expression in TNBC. The GPER mechanisms have been thoroughly characterized and analyzed in estrogen receptor α (ERα) positive breast cancer, but not in TNBC. Our previous work revealed that a higher expression of GPER mRNA indicates a better prognosis for ERα-positive breast cancer; however, its effects in TNBC differ. Whether GPER could serve as a predictive prognostic marker or therapeutic target for TNBC remains unclear. In this review, we provide a detailed introduction to the subcellular localization of GPER, the different effects of various ligands, and the interactions between GPER and closely associated factors in TNBC. We focused on the internal molecular mechanisms specific to TNBC and thoroughly explored the role of GPER in promoting tumor development. We also discussed the interaction of GPER with specific cytokines and chemokines, and the relationship between GPER and immune evasion. Additionally, we discussed the feasibility of using GPER as a therapeutic target in the context of existing studies. This comprehensive review highlights the effects of GPER on TNBC, providing a framework and directions for future research.

16.
J Craniofac Surg ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38451102

RESUMO

The treatment of complex intracranial aneurysms has always been a great challenge in neurosurgery. Craniotomy has a high risk of clipping, there is a risk of rupture at any time, endovascular embolization is relatively low risk, but expensive and easy to relapse, the best treatment needs to be further discussed. Cavernous sinus aneurysms with pituitary adenomas are rare. This case reports a case of complex intracranial aneurysms. Chief complaints are: (1) blepharoptosis with blurred vision for 1 year, (2) headache for 3 days, and (3) digital subtraction angiography showed right internal carotid artery cavernous sinus aneurysm. Combined with the patient's condition and family condition, the external carotid artery-radial artery-middle cerebral artery bypass was selected. After surgical treatment, the symptoms of the patients were improved, the postoperative recovery was good, and the condition was stable. After follow-up, the patient's brain computed tomography showed intra-aneurysm thrombosis.

17.
Food Chem ; 447: 138979, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38518617

RESUMO

Traditional Beijing roast duck often suffers from uneven color and high sugar content after roasting. Water-in-oil (W/O) nanoemulsion is a promising alternative to replace high concentration of sugar solution used in sugaring process according to similarity-intermiscibility theory. Herein, 3% of xylose was embedded in the aqueous phase of W/O emulsion to replace 15% maltose solution. W/O emulsions with different ratios of lecithin (LEC) and polyglycerol polyricinoleate (PGPR) were constructed by high-speed homogenization and high-pressure homogenization. Distribution and penetration extent of solutions and emulsions through the duck skin, as well as the color uniformity of Beijing roast duck were analyzed. Emulsions with LEC:PGPR ratios of 1:3 and 2:2 had better stability. Stable interfacial film and spatial structure were important factors influencing emulsion stabilization. The stable W/O emulsions could more uniformly distribute onto the surface of duck skin and longitudinally penetrate through the skin than solutions.


Assuntos
Patos , Glicerol/análogos & derivados , Lecitinas , Ácidos Ricinoleicos , Animais , Lecitinas/química , Emulsões/química , Açúcares , Água/química , Pequim
18.
Artigo em Inglês | MEDLINE | ID: mdl-38337117

RESUMO

The Arctic is particularly vulnerable to the impacts of climate change, of which vessel-source black carbon aerosols serving as a prominent catalyst for these changes. This situation is poised to worsen as sea ice melts and shipping lanes change. Rapid action aimed at mitigating short-term climate forcing factors can yield almost immediate climate benefits in the Arctic. This article provides an overview of the legal framework governing black carbon in the Arctic, considering three distinct perspectives: the global, regional, and national dimensions. These perspectives encompass global forums represented by the International Maritime Organization (IMO) and the United Nations Framework Convention on Climate Change (UNFCCC), with a focus on recent developments concerning black carbon governance, notably the amendments to MARPOL Annex VI and Annex I. Regionally, forums represented by the Arctic Council and the European Union are examined. Black carbon emissions exhibit migratory characteristics, yet the primary legal responsibilities for emission reduction are concentrated within Arctic states. Therefore, this article also delves into the laws and practices of Arctic coastal states in their efforts to combat black carbon emissions, using Canada and Norway as examples. The analysis of institutional effectiveness in this article indicates that, at present, specialized legislation on black carbon is either vague or non-existent. The current Arctic ship-source black carbon governance system faces issues related to leadership ambiguity in its institutional structure, a limited scope of responsible entities, and a lack of diverse implementation measures. Simultaneously, the governance system is questioned for having weak or non-legally binding regulations at the level of legal enforcement. The article anticipates the introduction of more mandatory regulations while also encouraging the selection of non-coercive policy tools. Accordingly, this article argues that a coordinated governance system centered on IMO and the Arctic Council needs to be established. Such a framework should adopt a more inclusive approach to stimulate positive interactions between regulations, aiming to create a broader winning alliance based on the existing foundations.

19.
J Hazard Mater ; 467: 133751, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38341884

RESUMO

Regulation of peroxymonosulfate (PMS) activation from radical to non-radical pathways is an emerging focus of advanced oxidation processes (AOPs) due to its superiority of anti-interference to complex wastewater. However, the detailed correlation mechanism between the defect structure of the catalyst and the regulation of radicals/non-radicals remains unclear. Herein, natural chalcopyrite (CuFeS2) with different levels of S vacancies created by a simple NaBH4 reduction process was employed to explore the above-mentioned underlying mechanism for constructing high efficiency and low cost of catalyst towards AOPs. With the assistance of simulated solar light, S-deficient chalcopyrite (Sv-NCP) exhibited prominent performance for PMS activation. More interestingly, the different degrees of S vacancies regulated the active species from radicals to non-radical 1O2, thus showing excellent purification of complex wastewater as well as actual pharmaceutical wastewater. Mechanistic analysis reveals that PMS tends to loss electrons on S vacancies sites and is dissociated into 1O2 rather than ·OH/SO4·- due to electron deficiency. Meanwhile, the improved adsorption performance makes the degradation sites of pollutants change from solution to surface. Most importantly, Sv-NCP presented excellent detoxication for antibiotic wastewater due to the high selectivity of 1O2. This work provides novel insights into the regulation of active species in Fenton-like reactions via defect engineering for high efficiency of pollutant degradation.

20.
Heliyon ; 10(3): e24883, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38318032

RESUMO

Rights and interests concerning the continental shelf beyond 200 nautical miles (extended continental shelf, ECS) are related to important aspects of a nation's marine utilization such as marine resource development, marine technological innovation, and the construction of marine ecological civilization. China is a country with a long coastline and has the right to delineate large areas of ECS according to the United Nations Convention on the Law of the Sea (UNCLOS). However, the process of confirming China's ECS rights under international law is particularly complicated owing to the complex maritime delineation disputes between China and its neighboring countries. From the perspective of international law, this study uses the method of historical analysis and case analysis to retrospectively explore the evolution of the international legal frameworks governing ECS and analyze its current characteristics and trends in practice. On this basis, the paper evaluates the major challenges of China's national practice in ECS delineation and puts forward suggested countermeasures for safeguarding its legitimate rights and interests related to ECS.

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