Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 123
Filtrar
1.
Ecol Evol ; 14(5): e11465, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38783848

RESUMO

The occurrence of interspecific feeding events, involving non-obligate nest parasite species, is rare but has been documented in numerous avian species worldwide, particularly in Europe and North America. Our report presents an observation from southwest China, where we observed a Greater Necklaced Laughingthrush (Pterorhinus pectoralis) nest containing three laughingthrush nestlings and two nestlings of Chestnut-winged Cuckoos (Clamator coromandus). They were being fed by the adult laughingthrush and a male White-browed Shrike-Babbler (Pteruthius aeralatus). However, after the cuckoo nestling fledged, we did not observe the Shrike-Babbler feeding the laughingthrush nestlings remaining in the nest. Through a systematic examination of potential driving factors, we infer that the begging calls of the cuckoo nestlings likely played a crucial role in the misfeeding events observed in our study. However, it is essential to consider the potential influence of the male shrike-babbler's status, including mateless, brood loss or female incubation. We highlight the further observations using digital recordings (for both images and sounds) to document detailed information on interspecific feeding events.

2.
BMC Musculoskelet Disord ; 25(1): 309, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38649917

RESUMO

BACKGROUND: Sarcopenia and multimorbidity are common in older adults, and most of the available clinical studies have focused on the relationship between specialist disorders and sarcopenia, whereas fewer studies have been conducted on the relationship between sarcopenia and multimorbidity. We therefore wished to explore the relationship between the two. METHODS: The study subjects were older patients (aged ≥ 65 years) who were hospitalized at the Department of Geriatrics of the First Affiliated Hospital of Chongqing Medical University between March 2016 and September 2021. Their medical records were collected. Based on the diagnostic criteria of the Asian Sarcopenia Working Group in 2019, the relationship between sarcopenia and multimorbidity was elucidated. RESULTS: 1.A total of 651 older patients aged 65 years and above with 2 or more chronic diseases were investigated in this study, 46.4% were suffering from sarcopenia. 2. Analysis of the relationship between the number of chronic diseases and sarcopenia yielded that the risk of sarcopenia with 4-5 chronic diseases was 1.80 times higher than the risk of 2-3 chronic diseases (OR 1.80, 95%CI 0.29-2.50), and the risk of sarcopenia with ≥ 6 chronic diseases was 5.11 times higher than the risk of 2-3 chronic diseases (OR 5.11, 95% CI 2.97-9.08), which remained statistically significant, after adjusting for relevant factors. 3. The Charlson comorbidity index was associated with skeletal muscle mass index, handgrip strength, and 6-meter walking speed, with scores reaching 5 and above suggesting the possibility of sarcopenia. 4. After adjusting for some covariates among 14 common chronic diseases in older adults, diabetes (OR 3.20, 95% CI 2.01-5.09), cerebrovascular diseases (OR 2.07, 95% CI 1.33-3.22), bone and joint diseases (OR 2.04, 95% CI 1.32-3.14), and malignant tumors (OR 2.65, 95% CI 1.17-6.55) were among those that still a risk factor for the development of sarcopenia. CONCLUSION: In the hospitalized older adults, the more chronic diseases they have, the higher the prevalence of sarcopenia. When the CCI is 5, attention needs to be paid to the occurrence of sarcopenia in hospitalized older adults.


Assuntos
Multimorbidade , Sarcopenia , Humanos , Sarcopenia/epidemiologia , Sarcopenia/diagnóstico , Idoso , Masculino , Feminino , Idoso de 80 Anos ou mais , Doença Crônica/epidemiologia , Pacientes Internados/estatística & dados numéricos , Fatores de Risco , Hospitalização/estatística & dados numéricos , Avaliação Geriátrica/métodos , China/epidemiologia , Estudos Retrospectivos
3.
Food Chem ; 450: 139324, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38615527

RESUMO

The abuse of tetracycline can lead to its residue in animal derived foods, posing many potential hazards to human health. Therefore, rapid and accurate detection of tetracycline is an important means to ensure food safety. Nitrogen doped and phosphorus doped silicon quantum dots (N-SiQDs, P-SiQDs) with remarkable optical stability were fabricated via a one-pot hydrothermal procedure in this study. Upon the excitation at 346 nm, N-SiQDs and P-SiQDs emitted fluorescence at 431 nm and 505 nm, respectively. Two SiQDs had the potential to serve as a probe for detecting low concentrations of tetracycline (TC), employing a mechanism of the static quenching effect. The calibration curves of N-SiQDs and P-SiQDs were linear within the range of 0-0.8 µM and 0-0.4 µM, the limits of detection were low as 5.35 × 10-4 µmol/L and 6.90 × 10-3 µmol/L, respectively. This method could be used successfully to detect TC in honey samples. Moreover, the remarkable antibacterial efficacy of two SiQDs could be attributed to the generation of a large number of intracellular reactive oxygen species. The SEM images showed that the structure of bacterial cell was disrupted and the surface became irregular when treated with both SiQDs. These properties enabled potential usage of SiQDs as excellent antibacterial material for different biomedical applications.


Assuntos
Antibacterianos , Contaminação de Alimentos , Mel , Pontos Quânticos , Silício , Tetraciclina , Pontos Quânticos/química , Mel/análise , Silício/química , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/análise , Tetraciclina/análise , Tetraciclina/farmacologia , Tetraciclina/química , Contaminação de Alimentos/análise , Fósforo/química , Nitrogênio/química
4.
Environ Sci Technol ; 58(13): 6007-6018, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38513264

RESUMO

Knowledge gaps in mercury (Hg) biomagnification in forest birds, especially in the most species-rich tropical and subtropical forests, limit our understanding of the ecological risks of Hg deposition to forest birds. This study aimed to quantify Hg bioaccumulation and transfer in the food chains of forest birds in a subtropical montane forest using a bird diet recorded by video and stable Hg isotope signals of biological and environmental samples. Results show that inorganic mercury (IHg) does not biomagnify along food chains, whereas methylmercury (MeHg) has trophic magnification factors of 7.4-8.1 for the basal resource-invertebrate-bird food chain. The video observations and MeHg mass balance model suggest that Niltava (Niltava sundara) nestlings ingest 78% of their MeHg from forest floor invertebrates, while Flycatcher (Eumyias thalassinus) nestlings ingest 59% from emergent aquatic invertebrates (which fly onto the canopy) and 40% from canopy invertebrates. The diet of Niltava nestlings contains 40% more MeHg than that of Flycatcher nestlings, resulting in a 60% higher MeHg concentration in their feather. Hg isotopic model shows that atmospheric Hg0 is the main Hg source in the forest bird food chains and contributes >68% in most organisms. However, three categories of canopy invertebrates receive ∼50% Hg from atmospheric Hg2+. Overall, we highlight the ecological risk of MeHg exposure for understory insectivorous birds caused by atmospheric Hg0 deposition and methylation on the forest floor.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Poluentes Químicos da Água , Animais , Mercúrio/análise , Cadeia Alimentar , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Florestas , Invertebrados , Aves , Isótopos , Isótopos de Mercúrio/análise
5.
Zookeys ; 1195: 139-155, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525353

RESUMO

Himalayan shrews of the genus Soriculus (Soricidae, Eulipotyphla), currently represented by four nominal species, are endemic to the Himalayas and the Gaoligong Mountains. In April 2022 and April 2023, a total of 10 specimens of Soriculus were collected from Beibeng and Damu, Medog County, Tibet, China. The morphology of the specimens was compared with the four recognised species of the genus Soriculus. Additionally, two mitochondrial (Cyt b and 12S) and three nuclear (APOB, BRCAI and RAG2) genes were sequenced to test the phylogenetic relationships of these specimens with the other species. Our results indicate that these specimens represent a distinct species, Soriculusbeibengensissp. nov., which is formally described here. The new species is distinguished from the other Soriculus species by the combination of darker pelages, smaller size, the relatively stubby nasal and the widened posterior processes of incisors. Phylogenetic analyses revealed the new species is sister to S.minor. The p-distance of Cyt b gene between S.beibengensis sp. nov. and other nominal Soriculus species ranges from 9.1-16.3%. This new species has a known distribution at an elevation of 1,500-2,125 m in Medog County, Tibet, China. The discovery of this new species from Medog County has important implications for interpreting small mammal biogeographic patterns in the eastern Himalaya and the mountain chains of south-west China.

6.
Int Orthop ; 48(6): 1489-1499, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38443716

RESUMO

PURPOSE: To compare the outcomes of type II pediatric phalangeal neck fractures (PPNFs) treated with closed reduction and cast immobilization (CRCI) versus closed reduction percutaneous pinning (CRPP), and evaluated the clinical efficacy of conservative versus surgical treatment of type II PPNFs via meta-analysis. METHODS: Patients aged ≤ 14 years with type II PPNFs were divided into conservative (CRCI) and operative (CRPP) groups. Radiographs measured angulation and translation; hand function was assessed with total active range of motion (TAM) and Quick-DASH. Complication rates were also compared between the groups. A meta-analysis of conservative versus operative treatment confirmed the clinical results. Statistical analysis was performed using SPSS 26.0 and R studio 3.0 with two-tailed, chi-squared, and Mann-Whitney U or t-tests, P < 0.05. Meta-analysis used fixed or random effects models, calculating mean differences and odds ratios for outcomes, and assessing heterogeneity with I2 and Q tests. RESULTS: Final angulation (3.4° ± 3.7° and 4.9° ± 5.4° vs. 3.6° ± 3.7° and 4.2° ± 4.3°) and displacement (6.3% ± 5.8% and 5.7% ± 4.7% vs. 5.8% ± 5.5% and 3.2% ± 4.2%) in the coronal and sagittal planes were not different statistically between the conservative and surgical groups (P > 0.05), but improved significantly compared to preoperative values (P < 0.05). Although Quick-DASH scores were comparable in both groups (P = 0.105), conservatively treated patients had a significantly better TAM at the last follow-up visit (P = 0.005). The complication rates were 24.2% and 41.7% in the surgical and conservatively treated groups respectively (P = 0.162). However, the latter primarily experienced imaging-related complications, whereas the former experienced functional complications (P = 0.046). Our meta-analysis (n = 181 patients) also showed comparable functional (P = 0.49) and radiographic (P = 0.59) outcomes and complication rates (P = 0.21) between the surgical (94 patients) and conservative (87 patients) groups. CONCLUSIONS: Conservative and surgical treatments are both reliable and safe approaches for managing type II PPNF in children. However, conservatively treated patients generally experience similar radiographic outcomes, lower complication rates, and better functional outcomes than surgically treated ones.


Assuntos
Fios Ortopédicos , Moldes Cirúrgicos , Falanges dos Dedos da Mão , Humanos , Criança , Falanges dos Dedos da Mão/lesões , Falanges dos Dedos da Mão/cirurgia , Masculino , Feminino , Adolescente , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/efeitos adversos , Resultado do Tratamento , Fraturas Ósseas/cirurgia , Amplitude de Movimento Articular , Pré-Escolar
7.
J Hazard Mater ; 468: 133783, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38367440

RESUMO

To elucidate the sources and transfer of mercury (Hg) in terrestrial food chains, particularly in heavily Hg-contaminated rice paddy ecosystems, we collected rice leaves, invertebrates, and Russet Sparrow nestlings from a clear food chain and analyzed the dietary compositions and potential Hg sources using stable Hg isotopes coupled with a Bayesian isotope mixing model (BIMM). Our findings indicated that MeHg exposure is dominant through the dietary route, with caterpillars, grasshoppers, and katydids being the main prey items, while the less provisioned spiders, dragonflies, and mantises contributed the most of the Hg to nestlings. We found minimal MIF but certain MDF in this terrestrial food chain and identified two distinct MeHg sources of dietary exposure and maternal transfer. We firstly found that the dietary route contributed substantially (almost tenfold) more MeHg to the nestlings than maternal transfer. These findings offer new insights into the integration of Hg from the dietary route and maternal transfers, enhancing our understanding of fluctuating Hg exposure risk during the nestling stage. Our study suggested that Hg isotopes combined with BIMM is an effective approach for tracing Hg sources in birds and for gaining in-depth insight into the trophic transfers and biomagnification of MeHg in food chains.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Odonatos , Oryza , Aves Canoras , Poluentes Químicos da Água , Animais , Isótopos de Mercúrio/análise , Cadeia Alimentar , Ecossistema , Bioacumulação , Teorema de Bayes , Mercúrio/análise , Isótopos , Monitoramento Ambiental , Poluentes Químicos da Água/análise
8.
J Hazard Mater ; 465: 133090, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38039814

RESUMO

Kashin-Beck disease is an endemic joint disease characterized by deep chondrocyte necrosis, and T-2 toxin exposure has been confirmed its etiology. This study investigated mechanism of T-2 toxin inducing mitochondrial dysfunction of chondrocytes through p53-cyclophilin D (CypD) pathway. The p53 signaling pathway was significantly enriched in T-2 toxin response genes from GeneCards. We demonstrated the upregulation of the p53 protein and p53-CypD complex in rat articular cartilage and ATDC5 cells induced by T-2 toxin. Transmission electron microscopy showed the damaged mitochondrial structure of ATDC5 cells induced by T-2 toxin. Furthermore, it can lead to overopening of the mitochondrial permeability transition pore (mPTP), decreased mitochondrial membrane potential, and increased reactive oxygen species generation in ATDC5 cells. Pifithrin-α, the p53 inhibitor, alleviated the increased p53-CypD complex and mitochondrial dysfunction of chondrocytes induced by T-2 toxin, suggesting that p53 played an important role in T-2 toxin-induced mitochondrial dysfunction. Mechanistically, T-2 toxin can activate the p53 protein, which can be transferred to the mitochondrial membrane and form a complex with CypD. The increased binding of p53 and CypD mediated the excessive opening of mPTP, changed mitochondrial membrane permeability, and ultimately induced mitochondrial dysfunction and apoptosis of chondrocytes.


Assuntos
Doenças Mitocondriais , Toxina T-2 , Ratos , Animais , Condrócitos/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Poro de Transição de Permeabilidade Mitocondrial/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Peptidil-Prolil Isomerase F , Ciclofilinas/genética , Ciclofilinas/metabolismo
9.
Environ Sci Pollut Res Int ; 30(51): 110869-110887, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37794226

RESUMO

It is unidentified whether information communication technology (ICT) agglomeration can contribute to carbon reduction and to what extent it plays a role in energy conservation and emission reduction, and further exploration is urgently needed. Based on the panel data of 108 cities in the Yangtze River Economic Belt from 2008 to 2019, the spatial panel Durbin model and intermediary effect model are employed to explore the effect of ICT agglomeration on carbon emissions and its pathways. It can be indicated from the results as below. (1) The local ICT agglomeration can reduce carbon emissions, but an increase in the level of ICT agglomeration in surrounding cities will increase local carbon emissions. (2) ICT agglomeration can reduce carbon emissions through reducing energy intensity and capital mismatch. (3) The effect of ICT agglomeration on carbon emissions is heterogeneous. ICT agglomeration can suppress carbon emissions in the middle and lower reaches of the Yangtze River, while it will increase carbon emissions in the upper reaches. ICT agglomeration increases carbon emissions in old industrial cities, reduces carbon emissions in non-old industrial cities, and has a more significant emission reduction effect in non-resource-based cities. We suggest promoting the formation of a coordinated linkage mechanism for ICT industry development and carbon emission reduction policies among regions, and implement differentiated ICT development strategies according to different industrial structure types.


Assuntos
Carbono , Rios , Carbono/análise , Cidades , Desenvolvimento Industrial , Desenvolvimento Econômico , Comunicação , China
10.
Nutr Rev ; 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37682265

RESUMO

CONTEXT: Coronavirus disease 2019 (COVID-19) could induce the "cytokine storm" due to overactivation of immune system and accompanied by acute respiratory distress syndrome as a serious complication. Vitamin C has been effective in improving lung function of patients by reducing inflammation. OBJECTIVE: The aim was to explore the therapeutic effects of high-dose vitamin C supplementation for patients with COVID-19 using meta-analysis. DATA SOURCES: Published studies were searched from PubMed, Cochrane Library, Web of Science, EMBASE, and China National Knowledge Infrastructure databases up to August 2022 using the terms "vitamin C" and "COVID-19". Data analyses were performed independently by 2 researchers using the PRISMA guidelines. DATA EXTRACTION: Heterogeneity between the included studies was assessed using I2 statistics. When I2 ≥50%, the random-effects model was used; otherwise, a fixed-effects model was applied. Stata 14.0 software was used to pool data by standardized mean differences (SMDs) with 95% CIs or odds ratios (ORs) with 95% CIs. DATA ANALYSIS: The 14 studies had a total of 751 patients and 1583 control participants in 7 randomized controlled trials and 7 retrospective studies. The vitamin C supplement significantly increased ferritin (SMD = 0.272; 95% CI: 0.059 to 0.485; P = 0.012) and lymphocyte count levels (SMD = 0.376; 95% CI: 0.153 to 0.599; P = 0.001) in patients with COVID-19. Patients administered vitamin C in the length of intensive care unit staying (SMD = 0.226; 95% CI: 0.073 to 0.379; P = 0.004). Intake of vitamin C prominently alleviate disease aggravation (OR = 0.344, 95%CI: 0.135 to 0.873, P = 0.025). CONCLUSIONS: High-dose vitamin C supplementation can alleviate inflammatory response and hinder the aggravation of COVID-19.

11.
PLoS One ; 18(9): e0291464, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37733717

RESUMO

It is important for China to break the "low-end lock" of the manufacturing value chain worldwide by revealing how digital trade promotes and reallocates the export technology complexity of the manufacturing industry. Panel data for 30 provinces in China from 2011 to 2020 were employed to measure the digital trade development and export technology complexity of the manufacturing industry. Benchmark regression, intermediary effect regression, panel threshold and other models were used to test the promotion and reallocation of digital trade on the export technology complexity of the manufacturing industry. The findings are as follows: (1) Digital trade promotes the export technology complexity of the manufacturing industry, with significant regional heterogeneity (eastern, central and western regions), and the most obvious promotion in technology-intensive manufacturing. (2) Technological innovation and human capital play a reallocation role in the process of digital trade, affecting the technological complexity of manufacturing exports, with mediating effects of 14.19% and 8.61%, respectively. (3) Digital trade promotes and reallocates the export technology complexity of the manufacturing industry through industrial structure upgrading, and a nonlinear relationship was found. These results provide empirical support and a decision-making basis for digital trade in promoting the export technology complexity of the manufacturing industry. The development of digital trade should be encouraged; the differential development of digital trade in the eastern, central, and western regions should be boosted; importance should be attached to the intermediary incentive role of technological innovation and human capital; and the upgrading of the industrial structure should be promoted scientifically.

12.
J Hazard Mater ; 459: 132263, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37573826

RESUMO

In order to comprehend the transfer of inorganic mercury (IHg) and methylmercury (MeHg) within food chains in terrestrial pine forests, we collected samples of Great Tit nestlings, common invertebrates, plants, and soil in a subtropical pine forest and used Bayesian isotope mixing model analysis, Hg daily intake, and stable Hg isotopes to elucidate the flow of MeHg and IHg in these food chains. Results indicate that caterpillars and cockroaches are the predominant prey items for nestlings, accounting for a combined contribution of 81.5%. Furthermore, caterpillars, cockroaches, and spiders were found to contribute the most (∼80%) of both IHg and MeHg that dietary accumulated in nestlings. The provisoned invertebrates tend to supply more IHg and diluting the proportion of MeHg as total Hg (MeHg%). Notably, nestling feathers displayed the highest Δ199Hg values but a relatively lower MeHg%, suggesting an imbalanced incorporation of Hg from maternal transfer and dietary accumulation during the nestling stage. This study highlights the efficacy of nestlings as indicators for identifying Hg sources and transfers in avian species and food chains. However, caution must be exercised when using Hg isotope compositions in growing feathers, and the contribution of maternally transferred Hg should not be ignored.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Aves Canoras , Poluentes Químicos da Água , Animais , Mercúrio/análise , Isótopos de Mercúrio/análise , Cadeia Alimentar , Teorema de Bayes , Compostos de Metilmercúrio/análise , Invertebrados/metabolismo , Florestas , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise
13.
Environ Sci Pollut Res Int ; 30(24): 65728-65745, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37093377

RESUMO

Based on the perspective of ecological security constraints, this research takes panel data of 42 counties (cities) in the urban agglomeration around Poyang Lake in China from 2000 to 2020 and uses a spatial econometric model to investigate the impact of transportation accessibility on industrial investment. The findings herein present an obvious spatial relationship between industrial investment among cities under ecological security constraints and reveal how transportation accessibility has a significant spatial effect on industrial investment in this area. Transportation accessibility has promoted industrial investment in the local region but restrained industrial investment in the surrounding areas. A series of endogenous and robustness tests strengthen this conclusion. Lastly, the effect of transportation accessibility on industrial investment in the UAAPYL is influenced by the lake's circle structure and shows obvious heterogeneity.


Assuntos
Lagos , Transporte de Pacientes , China , Indústrias , Cidades , Desenvolvimento Econômico
14.
Heliyon ; 9(1): e12812, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36699279

RESUMO

In this paper, a direct numerical simulation (DNS) of dielectric fluid flow subjected to unipolar injection under an alternating current (AC) electric field is carried out. The effect of frequency f of pulsed direct current (PDC) and AC on the transient evolution of electroconvection and their subcritical bifurcations are investigated in details. Electroconvection under PDC or AC tends to exhibit oscillating flow due to the periodic boundary condition of charge density and potential compared to the direct current (DC) case. The results demonstrate that under the PDC field, the linear criterion T c decreases with increasing frequency, while the nonlinear stability criterion T f is hardly affected. Under the AC field, a critical frequency f c  = 0.0316 is found, which separates electroconvection into two typical flow regimes-periodic flow regime (f < f c ) and inhibited flow regime (f ≥ f c )-depending on whether free charges can reach the collector electrode before electric field inversion. AC-electrohydrodynamics (EHD) systems promote various flow patterns with relatively lower voltage regimes than DC-EHD systems. These mechanisms of electroconvection under the PDC/AC field offer unique possibilities for fluid flow control in biological EHD-driven flow and portable EHD applications.

15.
Rev Sci Instrum ; 93(10): 104706, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36319321

RESUMO

The gyromagnetic nonlinear transmission line (GNLTL) is a special kind of coaxial transmission line partially loaded with the ferrite material. A GNLTL system can modulate the input high-power pulses into wideband high-power microwaves without relying on the electron beam and confining magnetic field. The unique working mechanism gives the GNLTL system the potential to be a small portable wideband high-power microwave radiation source. In this study, a wideband high-power microwave radiation source based on a GNLTL system is designed and constructed. In order to effectively radiate the wideband microwaves into the air, a high-power wideband Vlasov antenna and a special absorption high-pass filter are developed. The designs of key subsystems and high-power radiation experiments have been introduced and discussed in detail. In the test experiments, a radiated pulse with a peak electric field strength of 23 kV/m was measured at 20 m away from the transmitting antenna and the effective potential of radiation is 460 kV/m. The pulse width of the radiation pulse is about 4 ns, the center frequency is about 2.25 GHz, and the highest repetition rate can reach 25 Hz.

16.
Artigo em Inglês | MEDLINE | ID: mdl-36429516

RESUMO

Ecological welfare performance contributes directly to human well-being and regional sustainable development. Improving the regional ecological welfare performance in the process of pursuing green and sustainable development demands theoretical innovation and empirical exploration. Based on the super-efficiency SBM model, this study evaluated the ecological welfare performance of 108 cities during the period of 2009 to 2019. The Dagum Gini coefficient decomposition and spatial convergence model were employed to analyze the differences in ecological welfare performance across and within the study area and explore the underlining causes of such spatial differentiation in the Yangtze River Economic Belt and the upper, middle and lower reaches. It can be seen from the results that: (1) the overall difference in the ecological welfare performance of the Yangtze River Economic Belt is associated with a fluctuating downward trend during the study period. Regional and inter-regional differences were revealed and hypervariable density was identified as the main source of the differences. (2) The ecological welfare performance of the Yangtze River Economic Belt has absolute and conditional ß convergence, and the ecological welfare performance of each city-region and surrounding urban areas has a positive impact on each other. (3) The difference in the spatial-temporal differentiation trend is manifested by the difference in the convergence rate. The cities in the middle reaches of the Yangtze River have the fastest convergence rate, followed by the cities in the upper reaches, and the cities in the lower reaches are the slowest. This geographic difference is mainly driven by the combined effects of industrial structure, urban characteristics, environmental regulation, foreign direct investment, and transportation accessibility. Finally, it is proposed that future policies should focus on the imbalanced regional development in the study area, and each region needs to explore ways to improve local ecological welfare performance according to local conditions, and ultimately promote the overall green, coordinated and high-quality development in the Yangtze River Economic Belt.


Assuntos
Investimentos em Saúde , Rios , Humanos , Cidades , Indústrias , Desenvolvimento Sustentável
17.
Environ Sci Technol ; 56(19): 14154-14165, 2022 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-36150175

RESUMO

Plant roots are responsible for transporting large quantities of nutrients in forest ecosystems and yet are frequently overlooked in global assessments of Hg cycling budgets. In this study, we systematically determined the distribution of total Hg mass and its stable isotopic signatures in a subtropical evergreen forest to elucidate sources of Hg in plant root tissues and the associated translocation mechanisms. Hg stored in roots and its isotopic signatures show significant correlations to those found in surrounding soil at various soil depths. The odd mass-independent fractionation (MIF) of root Hg at a shallow soil depth displays a -0.10‰ to -0.50‰ negative transition compared to the values in aboveground woody biomass. The evidence suggests that root Hg is predominantly derived from surrounding soil, rather than translocation of atmospheric uptake via aboveground tissues. The cortex has a more negative mass-dependent fractionation (MDF) of -0.10‰ to -1.20‰ compared to the soil samples, indicating a preferential uptake of lighter isotopes by roots. The similar MDF and odd-MIF signals found in root components imply limited Hg transport in roots. This work highlights that Hg stored in plant roots is not a significant sink of atmospheric Hg. The heterogeneous distribution of Hg mass in roots of various sizes represents a significant uncertainty of current estimates of Hg pool size in forest ecosystems.


Assuntos
Mercúrio , Ecossistema , Monitoramento Ambiental , Florestas , Isótopos , Mercúrio/análise , Isótopos de Mercúrio/análise , Solo
18.
Environ Res ; 215(Pt 2): 114373, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36165871

RESUMO

Despite growing concerns over mercury (Hg) accumulation in birds in recent decades, little is known about Hg exposure in nocturnal migratory birds. Here, total mercury (THg) and methylmercury (MeHg) were detected in the feathers of nocturnal migratory birds (n = 286, belonging to 46 species) passing through Mount Ailao in Southwest China. The stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) were also determined to clarify the effects of trophic position, foraging guild, and foraging behavior on Hg bioaccumulation. Our results show that the THg and MeHg concentrations varied by two orders of magnitude among all nocturnal migratory birds investigated, with the lowest values (THg: 0.056 mg kg-1; MeHg: 0.038 mg kg-1) in the Asian koel (Eudynamys scolopaceus) and the highest (THg: 12 mg kg-1; MeHg: 7.8 mg kg-1) in the hair-crested drongo (Dicrurus hottentottus). Waterbirds showed higher δ15N values and higher THg and MeHg concentrations than songbirds, and the Hg concentrations in piscivorous species were significantly higher than those in herbivores, omnivores, and insectivores. Significant effects of foraging guilds (Kruskal-Wallis one-way ANOVA, p < 0.001) and foraging behaviors (Kruskal-Wallis one-way ANOVA, p < 0.001) on the Hg concentrations in migratory bird feathers were detected. A risk assessment indicated that approximately 7.0% of individuals were at moderate (2.4-5.0 mg kg-1) to high (>5.0 mg kg-1) risk of Hg exposure, and were therefore vulnerable to adverse physiological and behavioral effects. A long-term monitoring campaign during the migratory period is highly recommended to better understand the bioaccumulation of Hg in these nocturnal migratory bird populations over time.


Assuntos
Mercúrio , Compostos de Metilmercúrio , Aves Canoras , Poluentes Químicos da Água , Animais , Carbono , China , Monitoramento Ambiental , Mercúrio/análise , Nitrogênio , Poluentes Químicos da Água/análise
19.
Antioxidants (Basel) ; 11(8)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35892660

RESUMO

The application of cosmetics is indispensable in our current society. In recent years, with an increasing awareness of the long-term health benefits of naturally sourced ingredients, plant-based cosmetic products have gained increasing attention. Lilium belongs to the Liliaceae family, which is one of the main plant families used in cosmetics for skin care treatment. A large number of studies have shown that Lilium plants are rich in components such as phenolic acids, flavonoids, and polysaccharides, with high potential for cosmetic applications. However, the application of lilies in cosmetics has not been systematically reported. This knowledge gap can easily lead to the neglect of its application in cosmetics because lilies are most familiar as ornamental plants. Integrating academic papers and patent publications, we analyzed the potential cosmetic application ingredients in lily, as well as their applications in cosmetics and related efficacy. Patent analysis showed that applications for lily-related cosmetic patents are mainly concentrated in East Asia, including China, Korea, and Japan. The application of lilies involves all aspects of cosmetics, such as sunscreens, facial cleansers, facial masks, conditioners, and so on. Its functions are also rich and diverse, including antiaging, radiation protective, whitening, moisturizing, freckle removal, acne treatment, and hair regeneration promotion. In addition, lilies are compatible with the application of other herbs. Moreover, with a change in people's consumption concepts and the consideration of long-term health benefits, lily-based food and medicine innovation with health care and beautification effects may be a promising direction.

20.
Int J Pharm ; 624: 121981, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-35792228

RESUMO

Flavonoids have many positive pharmacological properties, such as antioxidant, antitumor, and anti-inflammatory activities. However, factors such as low water solubility and low dissolution rate limit their use. To overcome their poor solubility, carrier-free apigenin (API) microparticles and nanoparticles were prepared using three types of antisolvent precipitation technologies: supercritical antisolvent (SCF) technology, ultrasonic-assisted liquid antisolvent (UAL) technology, and high-pressure homogenization (HPH) technology. All three technologies can produce uniform tiny particles. However, the API particles obtained using these different techniques show subtle differences in terms of physical and chemical properties and biological activity. The preparation, characterization, and potential use of API microparticles and nanoparticles to improve in vitro release were studied. The resulting API particles were investigated and compared using Fourier-transform infrared spectroscopy, differential scanning calorimetry, X-ray powder diffraction, and scanning electron microscopy. We determined the optimum conditions for SCF, UAL, and HPH technologies to produce API microparticles and nanoparticles. The antioxidant and antitumor properties of the API particles were also investigated. The results demonstrated that the reduced particle size of the APIs prepared via SCF, UAL, and HPH technologies contributed to the enhanced dissolution rate, which in turn enhanced API bioactivity.


Assuntos
Apigenina , Nanopartículas , Antioxidantes , Apigenina/química , Varredura Diferencial de Calorimetria , Cristalização/métodos , Microscopia Eletrônica de Varredura , Nanopartículas/química , Tamanho da Partícula , Solubilidade , Solventes/química , Tecnologia , Ultrassom
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA