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1.
Lancet Reg Health West Pac ; 45: 101055, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38590780

RESUMO

Background: Perceived delays in cancer drug approvals have been a major concern for policymakers in China. Policies have been implemented to accelerate the launch of new cancer drugs and indications. This study aimed to assess similarities and differences between China and the United States in the approvals, timing, and clinical benefit evidence of cancer drug indications between 2001 and 2020. Methods: This study retrospectively identified all cancer drugs and indications approved in both China and the United States from January 1st, 2001 to December 31, 2020, and described differences in approval times as well as in submission and review times. Information on the availability of overall survival benefit evidence by December 31, 2020, was collected. Univariate and multiple logistic regression analyses were used to assess whether evidence of benefit and other factors affected the propensity and timing of approvals of cancer drug indications in China. Findings: Between 2001 and 2020, 229 indications corresponding to 145 cancer drugs approved in the United States were identified. Of those, 80 indications (34.9%) were also approved in China by the end of 2020. Cancer drug indications were approved in China at a median of 1273.5 days after approval in the United States. The median submission and review time differences for cancer drug indications in China were 1198.0 days and 180.0 days respectively. Submission time differences accounted for most of the approval time differences (p < 0.001). Indications supported by overall survival benefit evidence had shorter median review time differences (145.0 days) than those without such evidence (235.0 days, p = 0.008). Indications with overall survival benefit evidence were 3.94 times more likely to be approved in China compared to those without such evidence (p = 0.001), controlling for approval year, cancer type, and the prevalence of cancer by site. Interpretation: FDA-approved cancer drug indications demonstrating a survival benefit were more likely to receive approvals in China with shorter regulatory review times compared to indications without such evidence. Given that manufacturer submission times were the main driver of cancer drug approval times in China, factors influencing submission timing should be explored. Funding: No funding.

2.
Nat Commun ; 15(1): 3058, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594271

RESUMO

Versatile printing of polymers, metals, and composites always calls for simple, economic approaches. Here we present an approach to three-dimensional (3D) printing of polymeric, metallic, and composite materials at room conditions, based on the polymeric vapor-induced phase separation (VIPS) process. During VIPS 3D printing (VIPS-3DP), a dissolved polymer-based ink is deposited in an environment where nebulized non-solvent is present, inducing the low-volatility solvent to be extracted from the filament in a controllable manner due to its higher chemical affinity with the non-solvent used. The polymeric phase is hardened in situ as a result of the induced phase separation process. The low volatility of the solvent enables its reclamation after the printing process, significantly reducing its environmental footprint. We first demonstrate the use of VIPS-3DP for polymer printing, showcasing its potential in printing intricate structures. We further extend VIPS-3DP to the deposition of polymer-based metallic inks or composite powder-laden polymeric inks, which become metallic parts or composites after a thermal cycle is applied. Furthermore, spatially tunable porous structures and functionally graded parts are printed by using the printing path to set the inter-filament porosity as well as an inorganic space-holder as an intra-filament porogen.

3.
Front Pharmacol ; 15: 1292347, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38379900

RESUMO

Background: The clinical characteristics and risk factors of infusion reactions (IRs) are inadequately described in clinical practice due to underreported cases. In the present study, we reported the current status of IRs based on an in-hospital pharmacovigilance database of a tertiary care hospital. Methods: Our study conducted a retrospective analysis of drug-induced IRs recorded at an in-hospital pharmacovigilance center between January 2015 to December 2019. The descriptive statistical analysis encompassed main causative agents, clinical manifestations, organ/system involvement and outcome. The severity of IRs was assessed with reference to the CTCAE version 5.0 criteria and we investigated risk factors associated with severe IRs. Results: During the study period, a total of 505 cases of inpatient drug-induced IRs were detected, of which 79.2% (400 cases) were classified as general IRs and 20.8% (105 cases) were categorized as severe IRs. The primary drugs responsible for these reactions were antibiotics (23%, 116 cases), with piperacillin sodium-sulbactam sodium being the most prevalent, followed by antineoplastic agents (18.4%, 93 cases) and traditional Chinese medicine injections (TCMIs) (12.9%, 65 cases). The administration of cefoperazone - sulbactam, mannatide, Shenqi Fuzheng, elemene, and diterpene ginkgolides meglumine resulted in a higher incidence of critical IRs. Among all cases of IRs, 43.2%, 41.2%, and 23.4% showed signs and symptoms of circulation, skin mucosa, and respiratory organs/systems, respectively. 9.1% of cases experienced systemic damage, while 7.1% and 5.9% of cases reported neurological and gastrointestinal related adverse reactions, respectively. The multivariate analysis revealed that alcohol consumption (OR = 2.389%, 95% CI 1.141-5.002, p = 0.021), age over 65 (OR = 1.814%, 95% CI 1.052-3.127, p = 0.032) and the utilization of contrast media (OR = 4.072%, 95% CI 1.903-8.713, p < 0.001) were identified as risk factors for the development of severe IRs. Conclusion: Understanding the clinical characteristics of IRs helps to implement effective pharmaceutical monitoring and appropriate preventive measures for susceptible populations with risk factors.

4.
Sci Total Environ ; 913: 169407, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38123085

RESUMO

Soil organic carbon (SOC) plays a vital role in improving soil quality and alleviating global warming. Understanding the dynamic changes in SOC is crucial for its accumulation induced by compost application in agroecosystem. In this study, soil samples were collected from three treatments: high-rate bio-compost (BioMh), low-rate bio-compost (BioMl), and control (CK, no fertilization) during 2002-2020 in a wheat-maize double cropping system in North China. The soils were separated into three functional fractions, i.e., coarse particle organic matter (cPOM, >250 µm), microaggregates (µAgg, 53-250 µm) and mineral-associated organic matter (MAOM, < 53 µm), and the associated SOC contents were determined. During 1993-2002, SOC contents in bulk soil significantly increased with the duration in the BioMh and BioMl plots. However, there was no significant correlation between SOC content and duration during 2002-2020. These results suggested that compost application positively improved SOC sequestration, while the duration of SOC sequestration (i.e., the longevity of increased SOC with time) under compost inputs maintained only 9 years. Moreover, there was a significant increase in mean annual SOC contents in bulk soil with compost application rate during 2002-2020, indicating that carbon saturation did not occur. Additionally, the SOC contents in the cPOM fraction increased with time (p < 0.01), but the corresponding µAgg and MAOM associated SOC was insignificant (p > 0.05). The MAOM fraction exhibited no additional carbon accumulation with expanding compost application, confirming a hierarchical carbon saturation in these fractions. We concluded that soils under wheat-maize double cropping system in North China have greater potential to sequester C through additional compost inputs, despite showing hierarchical saturation behavior in the non-protected coarse particulate fraction.


Assuntos
Compostagem , Solo , Carbono/análise , Agricultura/métodos , Zea mays , Triticum , China , Sequestro de Carbono , Fertilizantes/análise
5.
BMC Cardiovasc Disord ; 23(1): 617, 2023 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-38097977

RESUMO

BACKGROUND: To analyze the association of serum Asprosin concentrations with heart failure (HF). METHODS: A total of 103 patients with HF were included in the HF group, and 103 patients with health checkups were included in the non-HF group. The serum Asprosin levels of the two groups were measured, and relevant clinical data were collected for statistical analysis. RESULTS: Compared with the non-HF group, the serum Asprosin concentration was significantly higher in the HF group, and the difference was statistically significant (P < 0.001). According to the serum Asprosin levels, we divided all the subjects into three quartiles. We found that the prevalence of HF increased with increasing serum Asprosin levels in the three groups (P < 0.001). Serum Asprosin levels were positively correlated with NT-ProBNP (P < 0.05) and negatively correlated with LVEF (P < 0.001). Dichotomous logistic regression analysis found Asprosin and age to be independent risk factors for HF (OR = 1.010, 95% CI: 1.003-1.018; OR = 1.058, 95% CI:1.004-1.665, respectively). Combining Asprosin and NT-proBNP indicators to draw ROC curves can improve the specificity and sensitivity of HF diagnosis. CONCLUSIONS: Serum Asprosin levels were significantly elevated in HF patients. The serum Asprosin level is an independent risk factor for HF, and the combined detection of Asprosin and NT-proBNP levels can improve the accuracy of HF diagnosis.


Assuntos
Insuficiência Cardíaca , Humanos , Insuficiência Cardíaca/diagnóstico , Curva ROC , Fatores de Risco , Peptídeo Natriurético Encefálico , Fragmentos de Peptídeos , Biomarcadores
6.
BMJ Glob Health ; 8(11)2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-38030227

RESUMO

BACKGROUND: China's National Reimbursement Drug List (NRDL) has become the primary route for drug reimbursement in China. More recently, the authority has made pharmacoeconomic evaluation an integral part of the application for NRDL inclusion. The underlying financial conflict of interests (FCOI) of pharmacoeconomic evaluations, however, has the potential to influence evidence generated and thus subsequent decision-making yet remains poorly understood. METHODS: We searched for studies published between January 2012 and January 2022 on the 174 drugs added to the 2017-2020 NRDLs after successful negotiation. We categorised the study's FCOI status into no funding, industry funding, non-profit funding and multiple fundings based on authors' disclosure and assessed the reporting quality of included studies using the Consolidated Health Economic Evaluation Reporting Standards 2022 checklist. We compiled descriptive statistics of funding types and study outcomes using t-tests and χ2 tests and conducted multivariate regression analysis. RESULTS: We identified 378 records and our final sample included 92 pharmacoeconomic evaluations, among which 69.6% were conducted with at least one funding source. More than half (57.6%) of the evaluations reached favourable conclusions towards the intervention drug and 12.6% reached a dominant result of the intervention drug over the comparison from model simulation. The reporting quality of included studies ranged from 19 to 25 (on a scale of 28), with an average of 22.3. The statistical tests indicated that industry-funded studies were significantly more likely to conclude that the intervention therapy was economical (p<0.01) and had a significantly higher proportion of resulting target drug economically dominated the comparison drug (p<0.05). CONCLUSION: The study revealed that FCOI bias is common in published pharmacoeconomic evaluations conducted in Chinese settings and could significantly influence the study's economical results and conclusions through various mechanisms. Multifaceted efforts are needed to improve transparency, comparability and reporting standardisation.


Assuntos
Farmacoeconomia , Negociação , Humanos , Custos de Medicamentos , Análise Custo-Benefício , China
7.
Enferm. infecc. microbiol. clín. (Ed. impr.) ; 41(9): 545-548, Nov. 2023. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-227270

RESUMO

Background: Psittacosis is a relatively uncommon cause of community-acquired pneumonia, often leading to diagnostic difficulty.Methods: A retrospective study was conducted on the clinical features of psittacosis patients in China. Forty-six cases of Chlamydophila psittaci infection with atypical pneumonia of varying severity in the last two years were described retrospectively.Results: Fever, relative bradycardia, and other systemic upsets were the main clinical presentation. The most common radiographic abnormality was segmental or lobar shadowing or consolidation. The total white cell counts were usually normal or slightly increased. The concentration of creatine kinase, C reactive protein, and lactic dehydrogenase increased, while albumin decreased remarkably. These cases exhibited good recovery after being treated with tetracycline or quinolone antibiotics.Conclusion: These features may help differentiate psittacosis from other traditional bacterial pneumonia. However, they do not provide a definitive diagnosis. Psittacosis diagnosis must perform the whole-genome sequencing for Chlamydophila psittaci in respiratory, blood, or sputum specimens. Increased awareness of psittacosis can shorten diagnostic delays and improve patient outcomes.(AU)


Antecedentes: La psitacosis es una causa relativamente poco común de neumonía adquirida en la comunidad, y a menudo conduce a dificultades diagnósticas.Métodos: Se realizó un estudio retrospectivo sobre las características clínicas de los pacientes con psitacosis en China, en el que se describen retrospectivamente 46 casos de infección por Chlamydia psittaci con neumonía atípica de gravedad variable en los últimos dos años.Resultados: La fiebre, la bradicardia relativa y otros trastornos sistémicos fueron la presentación clínica principal. La anomalía radiográfica más común fue el sombreado o consolidación segmentaria o lobular. Los recuentos totales de glóbulos blancos fueron generalmente normales o ligeramente aumentados. Las concentraciones de creatina quinasa, proteína C reactiva y deshidrogenasa láctica aumentaron, mientras que la albúmina disminuyó notablemente. Estos casos mostraron una buena recuperación después de ser tratados con antibióticos de tetraciclina o quinolona.Conclusión: Estas características pueden ayudar a diferenciar la psitacosis de otras neumonías bacterianas tradicionales. Sin embargo, no proporcionan un diagnóstico definitivo. El diagnóstico de psitacosis debe realizar la secuenciación del genoma completo de Chlamydia psittaci en muestras respiratorias, sanguíneas o de esputo. Una mayor conciencia de la psitacosis puede acortar los retrasos en el diagnóstico y mejorar los resultados de los pacientes.(AU)


Assuntos
Humanos , Masculino , Feminino , Psitacose/microbiologia , Pneumonia Associada a Assistência à Saúde , Chlamydophila psittaci , Bradicardia , Microbiologia , Doenças Transmissíveis , Psitacose/diagnóstico , China
8.
ACS Appl Mater Interfaces ; 15(26): 31502-31513, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37345282

RESUMO

The photoexcited charge separation efficiency of photocatalysts is generally considered as the key factor for enhancement of their photocatalytic activity, and sometimes, their photoabsorption capability and interfacial reaction kinetics play a key part, but the role of interfacial affinity of photocatalysts with substrates was rarely researched systematically. Herein, nitrogen vacancy-modified polymeric carbon nitride porous nanotubes (PCNpts) were simply synthesized, using tartaric acid as a crosslinking and corrosion agent, and exhibit a remarkable increment in surface area, wettability, photoabsorption and charge separation capability, and photocatalytic activity in water splitting to produce H2, but, interestingly, exhibit substrate-dependent variation of photoactivity in contaminant degradation, compared with bulk PCN. More interestingly, the interfacial affinity of PCNpts and PCN with contaminants and H2O, rather than photoabsorption and charge separation capability, is confirmed to dominate their photoactivity.

9.
Sci Total Environ ; 885: 163843, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37137362

RESUMO

Nitrogen (N) and phosphorus (P) are two crucial limiting mineral elements for terrestrial plants. Although the leaf N:P ratio is extensively used to indicate plant nutrient limitations, the critical N:P ratios cannot be universally applied. Some investigations have suggested that leaf nitrogen isotopes (δ15N) can provide another proxy for nutrient limitations along with the N:P ratio, but the negative relationships between N:P and δ15N were mainly limited to fertilization experiments. It will obviously benefit the study of the nature of nutrient limitations if the relationship could be explained more generally. We analyzed leaf δ15N, N, and P contents across a northeast-southwest transect in China. Leaf δ15N was weakly negatively correlated with leaf N:P ratios for all plants, while there was no correlation between them for various plant groups, including different growth forms, genera, and species across the entire N:P range. This suggests that the use of leaf δ15N in indicating the shift of nutrient limitations across the whole N:P range still requires more validated field investigations. Notably, negative relationships between δ15N and N:P hold for plants with N:P ratios between 10 and 20 but not for plants with N:P ratios lower than 10 or higher than 20. That is, changes in leaf δ15N along with the N:P ratio of plants that are co-limited by N and P can exhibit variations in plant nutrient limitations, whereas plants that are strictly limited by N and P cannot. Moreover, these relationships are not altered by vegetation type, soil type, MAP, or MAT, indicating that the use of leaf δ15N in reflecting shifts in nutrient limitations, depending on the plant nutrient limitation range, is general. We examined the relationships between leaf δ15N and the N:P ratio across an extensive transect, providing references for the widespread use of leaf δ15N in reflecting shifts in nutrient limitation.


Assuntos
Nitrogênio , Fósforo , Folhas de Planta , Plantas , China , Ecossistema , Nitrogênio/análise , Isótopos de Nitrogênio , Fósforo/análise , Folhas de Planta/química , Solo
10.
Plants (Basel) ; 12(7)2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37050177

RESUMO

The carbon, nitrogen and water cycles of terrestrial ecosystems are important biogeochemical cycles. Addressing the relationship of leaf nitrogen (N) and carbon isotope discrimination (Δ) will enhance the understanding of the links between these three cycles in plant leaves because Δ can reflect time-integrated leaf-level water-use efficiency (WUE) over the period when the leaf material is produced. Previous studies have paid considerable attention to the relationship. However, these studies have not effectively eliminated the interference of environmental factors, inter-species, and inter-individual differences in this relationship, so new research is necessary. To minimize these interferences, the present work explored the relationship at the three levels of community, population, and plant individual. Three patterns of positive, negative and no relationship were observed across communities, populations, and individuals, which is dependent on environmental conditions, species, and plant individuals. The results strongly suggested that there is no general pattern for the relationship between leaf N and Δ. Furthermore, the results indicated that there is often no coupling between leaf-level long-term WUE and leaf N in the metabolic process of carbon, N and water in leaves. The main reason for the lack of this relationship is that most plants do not invest large amounts of nitrogen into photosynthesis. In addition, the present study also observed that, for most plant species, leaf N was not related to photosynthetic rate, and that variations in photosynthetic rates are mainly driven by stomatal conductance.

11.
BMC Plant Biol ; 23(1): 155, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36945024

RESUMO

BACKGROUND: Understanding the relationship between human evolution and environmental changes is the key to lifting the veil on human origin. The hypothesis that environmental changes triggered the divergence of humans from apes (ca. 9.3-6.5 million years ago, Ma) has been poorly tested because of limited continuous environmental data from fossil localities. Lufengpithecus (12.5-6.0 Ma) found on the southeastern margin of the Tibetan Plateau (SEMTP) across the ape-human split provides a good chance for testing this hypothesis. RESULTS: Here, we reconstructed the habitats of L. keiyuanensis (12.5-11.6 Ma) with comprehensive vegetation, climate, and potential food web data by palaeobotanical evidence, together with other multidisciplinary data and partly tested the environment-driven hypothesis by revealing the living conditions of Lufengpithecus. CONCLUSION: A detailed comparison of hominoids on different continents reveals their behaviour and fate divergence across the ape-human split against the background of global climate change, i.e., the stable living conditions of SEMTP not only provided a so-called 'refuge' for arboreal Lufengpithecus but also acted as a 'double-edged sword', preventing their further evolution while vegetation shifts in East Africa probably stimulated the emergence of human bipedalism, and the intense climatic changes in Europe possibly prevented those hominoids from surviving that time interval. Our findings provide interesting insight into the environmental impacts on the behavioural evolution of hominoids.


Assuntos
Hominidae , Condições Sociais , Animais , Humanos , Filogenia , Ásia Oriental , Fósseis , Evolução Biológica
12.
Plants (Basel) ; 12(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36840299

RESUMO

Understanding the water use efficiency (WUE) and adaptation strategies of plants in high-temperature and rainy areas is essential under global climate change. The leaf carbon content (LCC) and intrinsic WUE of 424 plant samples (from 312 plant species) on Hainan Island were measured to examine their relationship with geographical and climatic factors in herbs, trees, vines and ferns. The LCC ranged from 306.30 to 559.20 mg g-1, with an average of 418.85 mg g-1, and decreased with increasing mean annual temperature (MAT). The range of intrinsic WUE was 8.61 to 123.39 µmol mol-1 with an average value of 60.66 µmol mol-1. The intrinsic WUE decreased with increasing altitude and relative humidity (RH) and wind speed (WS), but increased with increasing latitude, MAT and rainy season temperature (RST), indicating that geographical and climatic factors affect the intrinsic WUE. Stepwise regression suggested that in tropical regions with high temperature and humidity, the change in plant intrinsic WUE was mainly driven by WS. In addition, the main factors affecting the intrinsic WUE of different plant functional types of plants are unique, implying that plants of different plant functional types have distinctive adaptive strategies to environmental change. The present study may provide an insight in water management in tropical rainforest.

13.
Enferm Infecc Microbiol Clin (Engl Ed) ; 41(9): 545-548, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-36707280

RESUMO

BACKGROUND: Psittacosis is a relatively uncommon cause of community-acquired pneumonia, often leading to diagnostic difficulty. METHODS: A retrospective study was conducted on the clinical features of psittacosis patients in China. Forty-six cases of Chlamydophila psittaci infection with atypical pneumonia of varying severity in the last two years were described retrospectively. RESULTS: Fever, relative bradycardia, and other systemic upsets were the main clinical presentation. The most common radiographic abnormality was segmental or lobar shadowing or consolidation. The total white cell counts were usually normal or slightly increased. The concentration of creatine kinase, C reactive protein, and lactic dehydrogenase increased, while albumin decreased remarkably. These cases exhibited good recovery after being treated with tetracycline or quinolone antibiotics. CONCLUSION: These features may help differentiate psittacosis from other traditional bacterial pneumonia. However, they do not provide a definitive diagnosis. Psittacosis diagnosis must perform the whole-genome sequencing for Chlamydophila psittaci in respiratory, blood, or sputum specimens. Increased awareness of psittacosis can shorten diagnostic delays and improve patient outcomes.


Assuntos
Chlamydophila psittaci , Pneumonia Bacteriana , Psitacose , Humanos , Psitacose/diagnóstico , Psitacose/tratamento farmacológico , Estudos Retrospectivos , População do Leste Asiático , Pneumonia Bacteriana/microbiologia , Antibacterianos/uso terapêutico
14.
Environ Sci Pollut Res Int ; 30(4): 9022-9035, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35715679

RESUMO

Achieving the carbon neutrality in China has great impact on alleviating global warming. Compost application, an important measure to promote soil organic carbon (SOC) sequestration, has been practiced in China since 2015. However, it is still unclear how much carbon can be fixed by cropland soil under compost application in the whole China. China has pledged to strive for the goal of carbon neutrality by 2060, which brought two issues: whether compost application can consistently promote SOC sequestration until 2060, and how much contribution it can make to the carbon neutrality. In the present study, we analyzed the results from 93 literatures to determine the SOC sequestration under compost application in the different agricultural divisions of China. Results showed that there were regional differences in the effect of compost application on SOC sequestration. The annual SOC sequestration in Northern China (NC) and Gansu + Xinjiang (GX) was significantly high than other regions. In addition, the annual SOC sequestration was negatively related to the duration of the experiment, while the accumulative SOC sequestration during the experimental period increased with the increase of the duration. According to our results, the total SOC sequestration in topsoil of Chinese cropland was 85 Tg C year-1 under compost application, which will make a 4.4% contribution to carbon neutrality during 2021-2060. In conclusion, cropland soil in China can still sequester carbon for more than 35 years under compost application. Thus, abidingly promoting compost application in China is crucial to accomplishing the carbon neutrality goal.


Assuntos
Carbono , Compostagem , Agricultura/métodos , Carbono/análise , Sequestro de Carbono , China , Produtos Agrícolas , Solo
15.
ACS Appl Mater Interfaces ; 14(43): 49158-49170, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36269799

RESUMO

Hybrid materials based on transition metal carbide and nitride (MXene) nanosheets have great potential for electromagnetic interference (EMI) shielding due to their excellent electrical conductivity. However, the performance of final products depends not only on the properties of constituent components but also on the morphology of the assembly. Here, via the controlled diffusion of positively charged poly(allylamine hydrochloride) (PAH) chains into the negatively charged Ti3C2Tx MXene suspension, MXene/PAH hybrids in the forms of thin films, porous structures, and fibers with distinguished internal morphologies are obtained. Our results confirm that PAH chains could effectively enhance the oxidation stability and integrity of wet and dry MXene structures. The flexibility to tune the structures allows for a thorough discussion of the relations between the morphology, electrical conductivity, and EMI shielding mechanism of the hybrids in a wide range of electrical conductivity (2.5 to 3347 S·cm-1) and thickness (7.7 to 1900 µm) values. The analysis of thin films shows the direct impact of the polymer content on the alignment and compactness of MXene nanosheets regulating the films' electrical conductivity/EMI shielding effectiveness. The colloidal behavior of the initial MXene suspension determines the interconnection of MXene nanosheets in MXene/PAH porous assemblies and the final electrical properties. In addition to the internal morphology, examining the laminated MXene/PAH fibers with geometrically different arrangements demonstrates the role of conductive network configuration on EMI shielding performance. These findings provide insights into tuning the EMI shielding effectiveness via the charge-driven bottom-up assembly of electrically conductive MXene/polyelectrolyte hybrids.

16.
Sci Total Environ ; 851(Pt 1): 158145, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-35988622

RESUMO

How climate warming affected terrestrial ecosystems received considerable attention. Soil micronutrients play a vital role in regulating the growth of all living organisms and thus make a significant contribution to plant production. However, the responses of soil micronutrients to climate warming still remained unclear. While soil sampling along a temperature gradient could reveal the long-term influence of climate warming on soil nutrient dynamics, the variations of soil micronutrients with temperature might be interfered by the effect of precipitation due to the collinearity between temperature and precipitation. Moreover, changes in soil micronutrients over broad geographical scale could be affected by soil texture. Hence, this study conducted a soil investigation across a temperature transect along the 400 mm isohyet in northern China to examine the responses of soil micronutrients to changing temperature and soil texture when the effect of precipitation was minimized. We observed that soil copper (Cu), manganese (Mn) and zinc (Zn) contents all decreased along the temperature gradient. Soil Cu, Mn and Zn contents were positively correlated with soil clay and silt contents and negatively correlated with soil sand content. Temperature and soil texture together accounted for 72.0 % of the variations in soil micronutrient contents. Temperature and soil texture individually explained 10.4 % and 48.0 %, and their shared variation explained 13.6 % of the variations in soil micronutrient contents. Moreover, soil parent material also exerted an effect on soil micronutrient contents. Our results suggested that climate warming might cause a decrease in soil micronutrient contents.


Assuntos
Solo , Oligoelementos , China , Argila , Cobre , Ecossistema , Manganês , Micronutrientes , Areia , Temperatura , Zinco
17.
ACS Appl Mater Interfaces ; 14(11): 13419-13430, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35275489

RESUMO

Crystalline carbon nitride (CCN) with a poly(heptazine imide) structure is efficient in photocatalytic hydrogen evolution (PHE), but synthesis of CCN ultrathin nanosheets (CCNuns) and their use in PHE with selective organic oxidation are still rare. Herein, CCNuns with Na+ doping are prepared using NaCl as the ion-induction and templating agent and mesoporous melon as the feedstock, exhibiting efficient synchronous PHE and benzyl alcohol oxidation to benzaldehyde, with an apparent quantum yield of 10.5% at 420 nm and a visible light PHE rate that is 94.3 times that of bulk polymeric carbon nitride (PCN). The selectivity of benzaldehyde formation (90.5%) is also much higher than that of PCN (40.7%). Interestingly, this selectivity increases gradually with increasing light wavelengths. The high photoactivity of CCNuns originates from their ultrathinness and Na+ doping, which considerably enhance the photogenerated charge separation. This work opens up an avenue for the synthesis of CCNuns and extends their application.

18.
Chem Sci ; 13(3): 754-762, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35173940

RESUMO

Expediting the oxygen evolution reaction (OER) is the key to achieving efficient photocatalytic overall water splitting. Herein, single-atom Co-OH modified polymeric carbon nitride (Co-PCN) was synthesized with single-atom loading increased by ∼37 times with the assistance of ball milling that formed ultrathin nanosheets. The single-atom Co-N4OH structure was confirmed experimentally and theoretically and was verified to enhance optical absorption and charge separation and work as the active site for the OER. Co-PCN exhibits the highest OER rate of 37.3 µmol h-1 under visible light irradiation, ∼28-fold higher than that of common PCN/CoO x , with the highest apparent quantum yields reaching 4.69, 2.06, and 0.46% at 400, 420, and 500 nm, respectively, and is among the best OER photocatalysts reported so far. This work provides an effective way to synthesize efficient OER photocatalysts.

19.
Front Mol Neurosci ; 15: 1026927, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36698778

RESUMO

Introduction: Chemokine-like factor (CKLF)-like MARVEL transmembrane domain containing 6 (CMTM6) is a protein localized to the cell membrane and is known for its ability to co-localize with PD-L1 on the plasma membrane, prevent PD-L1 degradation, and maintain PD-L1 expression on the cell membrane. CMTM6 is highly expressed and plays an important role in various tumors such as oral squamous cell carcinoma (OSCC) and colorectal cancer (CRC), however, its role in Glioblastoma multiforme (GBM) is unclear. Methods: In this paper, to investigate the role of CMTM6 in GBM, we analyzed the expression of CMTM6 in GBM, the interaction with CMTM6 and the associated genes by bioinformatics. Importantly, we analyzed the expression of CMTM6 in GBM in relation to tumor-infiltrating lymphocytes (TILs), immunoinhibitors, immunostimulators, chemokines and chemokine receptors. We further analyzed the function of CMTM6 and performed in vitro experiments to verify it. Finally, the sensitivity of CMTM6 to drugs was also analyzed and the relationship between CMTM6 and the anticancer drug Piperlonguminine (PL) was verified in vitro. Results: The results showed that CMTM6 was highly expressed in GBM and correlated with multiple genes. Furthermore, CMTM6 is closely related to the immune microenvironment and inflammatory response in GBM. Bioinformatic analysis of CMTM6 correlated with the function of GBM, and our experiments demonstrated that CMTM6 significantly promoted the migration of GBM cells and epithelial-mesenchymal transition (EMT), but had no significant effect on other functions. Interestingly, we found that in GBM, PL promotes the expression of CMTM6. Discussion: In this paper, we have performed a detailed analysis and validation of the role of CMTM6 in GBM using bioinformatics analysis and in vitro experiments to demonstrate that CMTM6 may be a potential target for glioma therapy.

20.
PLoS One ; 16(10): e0258927, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34679096

RESUMO

Global changes in precipitation and atmospheric N deposition affect the geochemical cycle of the element and its hydrological cycle in the ecosystem. It may also affect the relationship between plant water use efficiency (WUE) and nutrients, as well as the relationship between plant nutrients. Desert ecosystems are vulnerable to global changes. Haloxylon ammodendron is the dominant species in the Asian desert. Revealing the variations in these relationships in H. ammodendron with precipitation and N deposition will enhance our understanding of the responses of plants to global change in terms of trade-off strategies of nutrient absorption, water and element geochemical cycles in desert ecosystems. Thus, we conducted field experiments with different amounts of water and N. This study showed that WUE of H. ammodendron was not correlated with nitrogen content (N), phosphorus content (P), and potassium content (K) when water and N supply were varied (p > 0.05 for WUE vs. N, P, and K), suggesting lack of coupling between water use and nutrient economics. This result was associated with the lack of correlation between plant nutrients and gas exchang in H. ammodendron. However, water addition, N addition and the interaction between both of them all played a role in the correlation between plant N, P and K owing to their different responses to water and N supplies. This indicates that global changes in precipitation and N deposition will affect N, P and K geochemical cycles in the Asian deserts dominated by H. ammodendron, and drive changes in the relationships between plant nutrients, resulting in changes in the trade-off strategy of plant absorption of N, P, and K.


Assuntos
Chenopodiaceae/fisiologia , Clima Desértico , Ecossistema , Solo/química , Água , Nitrogênio/análise , Fósforo/análise , Potássio/análise
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