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1.
Physiol Rep ; 12(19): e70068, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39358859

RESUMO

We sought to determine the repeatability of EFL in healthy adults during incremental cycle exercise. We hypothesized that the repeatability of EFL would be "strong" when assessed as a binary variable (i.e., absent or present) but "poor" when assessed as a continuous variable (i.e., % tidal volume overlap). Thirty-two healthy adults performed spirometry and an incremental cycle exercise test to exhaustion on two occasions. Standard cardiorespiratory variables were measured at rest and throughout exercise, and EFL was assessed by overlaying tidal expiratory flow-volume and maximal expiratory flow-volume curves. The repeatability of EFL was determined using Cohen's κ for binary assessments of EFL and intraclass correlation (ICC) for continuous measures of EFL. During exercise, n = 12 participants (38%) experienced EFL. At peak exercise, the repeatability of EFL was "minimal" (κ = 0.337, p = 0.145) when assessed as a binary variable and "poor" when measured as a continuous variable (ICC = 0.338, p = 0.025). At matched levels of minute ventilation during high-intensity exercise (i.e., >75% of peak oxygen uptake), the repeatability of EFL was "weak" when measured as a binary variable (κ = 0.474, p = 0.001) and "moderate" when measured as a continuous variable (ICC = 0.603, p < 0.001). Our results highlight the day-to-day variability associated with assessing EFL during exercise in healthy adults.


Assuntos
Teste de Esforço , Exercício Físico , Humanos , Masculino , Feminino , Adulto , Exercício Físico/fisiologia , Teste de Esforço/métodos , Teste de Esforço/normas , Reprodutibilidade dos Testes , Volume de Ventilação Pulmonar/fisiologia , Espirometria/métodos , Adulto Jovem , Consumo de Oxigênio/fisiologia
2.
Radiol Case Rep ; 19(12): 6068-6071, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39380829

RESUMO

Spinal schwannomas are benign lesions that most commonly appear in the lumbar and thoracic regions of the spine. Although computed tomography (CT) scans are often used to assess spinal conditions, they are ineffective at detecting soft tissue abnormalities. This case is for a 49-year-old female who experienced a gradual loss of sensation and strength in her lower extremities, along with increased urinary urgency, over six weeks. In addition, mid-back pain has been present for one year. Initially, a CT scan was done and did not show any significant findings, which suggested the absence of a spinal abnormality. However, magnetic resonance imaging (MRI) revealed an intradural extramedullary lesion causing spinal cord compression. The patient successfully underwent surgery to remove the tumor, and histological analysis confirmed it as spinal schwannoma. This case underlines the diagnostic limitations of CT imaging for spinal lesions and illustrates the superior accuracy of MRI. Thus, a negative CT should not halt further diagnostic evaluation when symptoms persist.

3.
Proc Natl Acad Sci U S A ; 121(42): e2410736121, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39383003

RESUMO

Allometric scaling relations are widely used to link biological processes to body size in nature. Several studies have shown that such scaling laws hold also for natural ecosystems, including individual trees and forests, riverine metabolism, and river network organization. However, the derivation of scaling laws for catchment-scale water and carbon fluxes has not been achieved so far. Here, we focus on scaling relations of catchment green metabolism, defined as the set of ecohydrological and biogeochemical processes through which vegetation assemblages in catchments maintain their structure and react to the surrounding environment. By revising existing plant size-density relationships and integrating them across large-scale domains, we show that the ecohydrological fluxes occurring at the catchment scale are invariant with respect to the above-ground vegetation biomass per unit area of the basin, while they scale linearly with catchment size. We thus demonstrate that the sublinear scaling of plant metabolism results in an isometric scaling at catchment and regional scales. Deviations from such predictions are further shown to collapse onto a common distribution, thus incorporating natural fluctuations due to resource limitations into a generalized scaling theory. Results from scaling arguments are supported by hyperresolution ecohydrological simulations and remote sensing observations.

4.
Channels (Austin) ; 18(1): 2402749, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39383513

RESUMO

Kcv channels from plant viruses represent the autonomous pore module of potassium channels, devoid of any regulatory domains. These small proteins show very reproducible single-channel behavior in planar lipid bilayers. Thus, they are an optimum system for the study of the biophysics of ion transport and gating. Structural models based on homology modeling have been used successfully, but experimental structural data are currently not available. Here we determine the size of the cytosolic pore entrance by studying the blocker kinetics. Blocker binding and dissociation rate constants ranging from 0.01 to 1000 ms-1 were determined for different quaternary ammonium ions. We found that the cytosolic pore entrance of KcvNTS must be at least 11 Å wide. The results further indicate that the residues controlling a cytosolic gate in one of the Kcv isoforms influence blocker binding/dissociation as well as a second gate even when the cytosolic gate is in the open state. The voltage dependence of the rate constant of blocker release is used to test, which blockers bind to the same binding site.


Assuntos
Canais de Potássio , Compostos de Amônio Quaternário , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/metabolismo , Compostos de Amônio Quaternário/farmacologia , Cinética , Canais de Potássio/metabolismo , Canais de Potássio/química , Bloqueadores dos Canais de Potássio/farmacologia , Bloqueadores dos Canais de Potássio/química , Bloqueadores dos Canais de Potássio/metabolismo , Sítios de Ligação , Ativação do Canal Iônico , Proteínas Virais/metabolismo , Proteínas Virais/química
5.
Artigo em Inglês | MEDLINE | ID: mdl-39384675

RESUMO

Ecoenzymatic stoichiometry can reflect the ability of soil microorganisms to acquire energy and nutrients and to determine their response to environmental stresses. However, the drivers of metabolic limitation of the moss biocrust microbiome during the ecological restoration of coal mining areas are poorly understood. Therefore, in this study, enzymatic stoichiometry modeling and high-throughput sequencing were used to simultaneously determine moss biocrust microbial metabolic limitation and its relationship with moss biocrust nutrients and arbuscular mycorrhizal fungal (AMF) diversity in five arid and semi-arid revegetation types (Hippophae rhamnoides, Amorpha fruticosa, Cerasus humilis, Cerasus szechuanica, and Xanthoceras sorbifolium) and two microbial treatments (AMF-inoculated and uninoculated). The activities of moss biocrust carbon (C)-, nitrogen (N)-, and phosphorus (P)-acquiring enzymes and organic carbon fractions in the AMF-inoculated treatment were significantly higher than those in the uninoculated control. Moss biocrust microbial community C and P limitations were observed in the five revegetation types, with lower limitation in general in the AMF-inoculated treatment. Dinitrogen-fixing plants (Amorpha fruticosa and Hippophae rhamnoides) significantly mitigated moss biocrust microbiome C and P limitation, especially in the AMF-inoculated treatment. Furthermore, partial least squares path modeling (PLS-PM) shows that moss biocrust organic carbon fractions (- 0.73 and - 0.81 of the total effects, respectively) and AMF diversity (- 0.73 and - 0.81 of the total effects) had negative effect on microbial C and P limitation, suggesting that more efficient active nutrients and AMF diversity are important factors alleviating limitation of moss biocrust microbial metabolism. This indicates that moss biocrust microbial communities under N2-fixing species with AMF inoculation were more stable under environmental stress; thus, AMF inoculation and/or N2-fixing plants may be recommended as preferred options for the ecological restoration of arid mining areas.

7.
Artigo em Inglês | MEDLINE | ID: mdl-39360341

RESUMO

OBJECTIVE: The biomechanics of upper airway collapse in obstructive sleep apnea (OSA) remains poorly understood. The goal of this study is to compare the area-pressure relationship (tube law) of the velopharynx at peak inspiration and peak expiration. STUDY DESIGN: Cross-sectional. SETTING: Academic tertiary medical center. METHODS: The velopharyngeal tube law was quantified in a convenience sample of 20 OSA patients via step reductions in nasal mask pressure during drug induced sleep endoscopy (DISE). The velopharyngeal airspace cross-sectional area was estimated from endoscopy while luminal pressure was recorded with a catheter. The tube law was quantified for nasal mask pressures from 14 to 0 cmH2O at peak inspiration and at peak expiration in all patients. The tube law was also quantified during the breathing cycle at a constant nasal mask pressure of 4 cmH2O in 3 patients representing different phenotypes. RESULTS: Velopharyngeal compliance (the slope of the tube law) was not statistically different in the peak inspiration versus peak expiration tube laws. Three phenotypes were observed, namely inspiratory collapse (phenotype 1), expiratory collapse (phenotype 2 = palatal prolapse), and a mostly stable airway during inspiration and expiration that collapsed as CPAP was reduced (phenotype 3). CONCLUSION: Velopharyngeal compliance is not significantly different at peak inspiration and peak expiration, which suggests that muscle tone is low when luminal pressure is above the closing pressure. Additional studies are needed to investigate how different phenotypes of velopharyngeal collapse may affect therapeutic outcomes.

8.
Artigo em Inglês | MEDLINE | ID: mdl-39361123

RESUMO

OBJECTIVE: We test the Racial Context Hypothesis by examining the association between racial context of origin and five physical health outcomes (self-rated health, activity limitation, functional activity limitation, lifetime hypertension, and lifetime cancer) among U.S.-born Black Americans and Black immigrants in the United States. DESIGN: This cross-sectional study used 2000 through 2018 waves of the National Health Interview Survey (NHIS). Our subsample was limited to adults 18 years of age or older who self-identified as Black and selected a distinct global region of birth if not U.S. born (N = 212,269). We employed zero-order logistic regression models to estimate the relationships between each measure of health and racial context by region of birth. RESULTS: Supporting the Racial Context Hypothesis, we found Black immigrants from racially mixed (Mexico, Central America, the Caribbean, South America) and majority-Black contexts (Africa) had lower odds of being in fair or poor self-rated health [aOR 0.786; 0.616; 0.611], reporting any activity limitation [aOR = 0.537; 0.369; 0.678], reporting functional activity limitation [aOR 0.619; 0.425; 0.678], reporting lifetime hypertension diagnosis [aOR 0.596; 0.543; 0.618], and reporting lifetime cancer diagnosis [aOR 0.771; 0.326; 0.641] compared to U.S.-born Black Americans. After controlling for sociodemographic and socioeconomic covariates, Black immigrants from majority-White contexts (Europe) did not significantly differ from U.S.-born Black Americans on these five physical health measures. CONCLUSION: This study expands our understanding of the "Black immigrant advantage" by showing that Black immigrants from predominantly Black and racially mixed regions rated their health status as poor or fair less often, experienced less activity or functional activity limitations, and had a lower risk of lifetime hypertension and cancer compared to U.S.-born Black Americans. The significant associations persisted even after controlling for sociodemographic and socioeconomic characteristics. Black immigrant health is not homogenous, and the racial context of origin Black immigrants come from has an association with their health outcomes.

9.
Chemosphere ; : 143496, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39374674

RESUMO

Plants require nutrients for growth, which they obtain from the soil via the root system. Fertilizers offer the essential nutrients (nitrogen, phosphorus, and potassium, as well as critical secondary elements) required by plants. Soil productivity falls with each crop until nutrients are provided. A wide range of so-called fertilizer products, such as organic fertilizers, argon mineral fertilizers, and mineral fertilizers, can assist farmers in adjusting fertilization methods based on the environment and agricultural conditions (inhibitors, restricted materials, growth mediums, plant bio-stimulants, etc.). Agricultural land is reduced by erosion, pollution, careless irrigation, and fertilization. On the other hand, more agricultural production is needed to meet the demands of expanding industries and the nutritional needs of a growing population. Nano fertilizers have recently started to be manufactured to obtain the highest yield and its quality per unit area. Previous researchers found that nano fertilizers could improve plant nutrient uptake efficiency, lower soil toxicity, mitigate the potential negative effects of excessive chemical fertilizer use, and reduce the frequency of fertilization. To maximize crop yields and optimize nutrient use while reducing the overuse of chemical fertilizers, nano fertilizersNFs are crucial in agriculture. The key component of these fertilizers is that they contain one or more macro- and micronutrients that can be applied regularly in minute doses while not damaging the environment. However, they have a minimal effect on plant growth and agricultural yields when employed in high numbers, like synthetic fertilizers. This article explains the features, relevance and classification of nano-fertilizers, their use in plant development, their advantages and disadvantages, and the results achieved in this field.

10.
3 Biotech ; 14(10): 254, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39350933

RESUMO

The effects of four initial culture pH values (3, 4, 5, and 6) and nitrogen limitation on growth, TAG accumulation, lipid production, fatty acid profile, and estimated biodiesel quality of Starmerella magnoliae X3 were investigated. TAG and lipid levels were measured by Nile Red fluorescence and sulfo-phospho-vanilin (SPV) techniques, respectively. The results showed that a combination of nitrogen limitation and acidic pH significantly (p < 0.05) increased TAG accumulation, total lipid contents, and lipid productivity in Starmerella magnoliae X3 compared to the control group. Under nitrogen limitation, the highest TAG accumulation was achieved at initial pHs of 3 and 5 after 72 h of cultivation, and the highest lipid productivity (0.306 g L-1 d-1) was observed after 48 h at pH 3; the major fatty acids at the four pH values were oleic acid (63.6%-64%), palmitoleic acid (11.3%-12.5%), stearic acid (9.7%-11.4%), and palmitic acid (9.4%-10%). In addition, both stresses were associated with lower iodine value and higher cetane number of the biodiesel compared to the control. These findings suggest that cultivation in a low-nitrogen medium at an initial pH of 3 or 5 holds promise in increasing TAG production in Starmerella magnoliae X3.

11.
Mol Ecol ; : e17540, 2024 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-39377248

RESUMO

Although patterns of population genomic variation are well-studied in animals, there remains room for studies that focus on non-model taxa with unique biologies. Here we characterise and attempt to explain such patterns in mygalomorph spiders, which are generally sedentary, often occur as spatially clustered demes and show remarkable longevity. Genome-wide single nucleotide polymorphism (SNP) data were collected for 500 individuals across a phylogenetically representative sample of taxa. We inferred genetic populations within focal taxa using a phylogenetically informed clustering approach, and characterised patterns of diversity and differentiation within- and among these genetic populations, respectively. Using phylogenetic comparative methods we asked whether geographical range sizes and ecomorphological variables (behavioural niche and body size) significantly explain patterns of diversity and differentiation. Specifically, we predicted higher genetic diversity in genetic populations with larger geographical ranges, and in small-bodied taxa. We also predicted greater genetic differentiation in small-bodied taxa, and in burrowing taxa. We recovered several significant predictors of genetic diversity, but not genetic differentiation. However, we found generally high differentiation across genetic populations for all focal taxa, and a consistent signal for isolation-by-distance irrespective of behavioural niche or body size. We hypothesise that high population genetic structuring, likely reflecting combined dispersal limitation and microhabitat specificity, is a shared trait for all mygalomorphs. Few studies have found ubiquitous genetic structuring for an entire ancient and species-rich animal clade.

12.
AoB Plants ; 16(5): plae045, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39363930

RESUMO

Increasingly frequent heat waves threaten the reproduction of flowering plants; compromising the future persistence, adaptive capacity, and dispersal of wild plant populations, and also the yield of fruit-bearing crop plants. Heat damages the development of sensitive floral organs and gametes, which inhibits pollen germination, pollen tube growth, and fertilization. However, the role of heat has not been integrated into the framework of pollen quantity and quality limitation and how heat influences the success of cross and self-pollination. We exposed developing flowers to either controlled temperature (25 °C:20 °C) or extreme heat (35 °C:20 °C) over 72 h. We then hand-pollinated them with either crossed or self-derived pollen from the same temperature treatment to determine the direct and interactive effects of simulated heatwaves on pollen tube growth and resulting seed set. We also collected anthers from virgin flowers to measure heat impacts on pollen production. Under cooler control temperatures pollen tube survival of self-derived pollen was approximately 27% lower than that of crossed pollen. Pollen tube survival in heat-treated cross-pollinated and heat-treated self-pollinated flowers were 71% and 77% lower compared to flowers cross-pollinated at control temperatures. These differences in pollen tube survival rate between heat-treated cross-pollinated and heat-treated self-pollinated flowers were insignificant. Furthermore, extreme heat reduced seed set by 87%, regardless of pollen origin, and also reduced pollen production during flower development by approximately 20%. Our results suggest flowers that develop during heatwaves are likely to experience exacerbated pollen quantity and quality limitation driven by changes in pollen production and pollen vigour. Heatwave-induced pollen limitation will likely reduce crop yields in agricultural systems, and depress mating and reproduction in wild plant species, the latter of which may hinder the adaptive capacity of plants to a rapidly changing world.

13.
Front Pharmacol ; 15: 1476228, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39364058

RESUMO

Photodynamic Therapy (PDT), as a minimally invasive treatment method, has demonstrated its distinct advantages in the management of skin malignant tumors. This article examines the current application status of PDT, assesses its successful cases and challenges in clinical treatment, and anticipates its future development trends. PDT utilizes photosensitizers to interact with light of specific wavelengths to generate reactive oxygen species that selectively eradicate cancer cells. Despite PDT's exceptional performance in enhancing patients' quality of life and prognosis, the limitation of treatment depth and the side effects of photosensitizers remain unresolved issues. With the advancement of novel photosensitizers and innovative treatment technology, the application prospects of PDT are increasingly expansive. This article delves into the mechanism of PDT, its application in various skin malignancies, its advantages and limitations, and envisions its future development. We believe that through continuous technological enhancements and integration with other treatment technologies, PDT has the potential to assume a more pivotal role in the treatment of skin malignancies.

14.
Respir Res ; 25(1): 357, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39358782

RESUMO

BACKGROUND: Expiratory flow limitation (EFL) can be detected using oscillometric reactance and is associated with a worse clinical presentation in chronic obstructive pulmonary disease (COPD). Reactance can show negative swings upon exhalation, which may develop at different rates between patients. We propose a new method to quantify the rate of EFL development; the EFL Development Index (ELDI). METHODS: A retrospective analysis of data from 124 COPD patients was performed. Data included lung function tests, Impulse Oscillometry (IOS), St Georges Respiratory Questionnaire (SGRQ), modified Medical Research Council (mMRC) scale and COPD Assessment Test (CAT) score. Fifty four patients had repeat data after 6 months. Twenty two patients had data recorded after 5 days of treatment with long acting bronchodilator therapy. EDLI was calculated as the mean expiratory reactance divided by the minimum expiratory reactance. RESULTS: The mean ELDI was used to categorise patients with rapid onset of EFL (> 0.63; n = 29) or gradual onset (≤ 0.63; n = 34). Those with rapid development had worse airflow obstruction, lower quality of life scores, and greater resting hyperinflation, compared to those with gradual development. In patients with EFL, ELDI correlated with symptoms scores, airflow obstruction, lung volumes and gas diffusion. Both EFL and ELDI were stable over 6 months. EFL and EDLI improved with bronchodilator treatment. CONCLUSIONS: COPD patients with rapid EFL development (determined by ELDI) had worse clinical characteristics than those with gradual EFL development. The rate of EFL development appears to be associated with clinical and physiological characteristics.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Mecânica Respiratória , Humanos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Masculino , Feminino , Estudos Retrospectivos , Idoso , Pessoa de Meia-Idade , Mecânica Respiratória/fisiologia , Testes de Função Respiratória/métodos , Broncodilatadores/uso terapêutico , Broncodilatadores/administração & dosagem , Oscilometria/métodos , Volume Expiratório Forçado/fisiologia
15.
Disabil Rehabil ; : 1-6, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225107

RESUMO

PURPOSE: To translate and cross-culturally adapt The Brachial Assessment Tool (BrAT) into Danish and assess its content validity and reproducibility in adults with traumatic brachial plexus injury (BPI). MATERIAL AND METHODS: Translation followed international guidelines. BrAT(DK) were cognitive tested with 19 adults with traumatic BPI to evaluate cross-cultural understanding, relevance, comprehensiveness and comprehensibility. Content validity and reproducibility were evaluated following the COnsensus-based Standards for the selection of health Measurement INstruments guideline. Participants were recruited from an outpatient hand clinic. Test-retest reliability was assessed using intra-class-correlation coefficient (ICC) and the smallest detectable change (SDC). Internal consistency was evaluated using Cronbach's alpha. RESULTS: Minor cultural differences were observed in the content validity analysis of BrAT(DK). Cognitive testing revealing no significant issues. All participants found the items relevant and important. 63 participants with traumatic BPI were recruited; 49 completed the retest. ICC values for the sub-scales and the total score ranged from 0.91 to 0.95 (95% CI 0.85 to 0.97). Internal consistency ranged from 0.87 to 0.98. SDC ranged from 4.16 to 9.63 for subscales and 16.01 for the total score. CONCLUSION: BrAT(DK) appeared to be content valid and reliabel as a measure of activity limitation in adults with traumatic BPI.


The Brachial Assessment Tool (BrAT) has been cross-cultural translated into DanishBrAT(DK) shows adequate content validity for activity limitation in adults with traumatic brachial plexus injuryBrAT(DK) is a reliable measure, with a smallest detectable change of 16.01 points for the total scaleWe recommend the use of BrAT(DK) in clinical practice to inform goal setting and future interventions and treatment evaluations.

16.
Physiother Res Int ; 29(4): e2127, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39234855

RESUMO

BACKGROUND AND PURPOSE: Diabetic polyneuropathy is a long-standing microvascular complication of diabetes that affects the postural control and functional mobility of patients. There are other microvascular complications, including pulmonary complications that reduce lung function. Multifactorial Inspiratory Muscle Training (IMT) can act as a home-based technique targeted to affect both these complications. This study aims to determine the effects of IMT on respiratory and functional parameters in diabetic polyneuropathy patients. METHODS: This is a Pre-Test Post-Test Randomized Controlled Trial (NCT#04947163) with 62 diabetic polyneuropathy patients. Each was randomly assigned to the IMT or sham-IMT group. Both the groups performed OTAGO exercises , with the sham-IMT group performing IMT at 15% of baseline maximal inspiratory pressure (MIP), whereas IMT were trained at 50% of baseline MIP as an initial intensity, which was increased as per the tolerance of patients. Both groups performed training for 12 weeks. The study investigated diaphragmatic strength, pulmonary function, functional capacity through 6MWT, 30s sit to stand test and anterior trunk muscle endurance tested through sit up test as outcome variables. Data was analysed on SPSS v26 at the significance level of 0.0.5. RESULTS: The IMT group significantly improved diaphragmatic strength, pulmonary function, 6MWT and anterior trunk muscle endurance when compared to the sham-IMT group. CONCLUSION: The study concluded that home-based IMT can improve pulmonary parameters including diaphragmatic strength and lung function as well as functional parameters including functional capacity in patients with diabetic polyneuropathy. The study was registered at ClinicalTrials.gov, NCT#04947163.


Assuntos
Exercícios Respiratórios , Neuropatias Diabéticas , Força Muscular , Músculos Respiratórios , Humanos , Masculino , Feminino , Neuropatias Diabéticas/reabilitação , Neuropatias Diabéticas/fisiopatologia , Pessoa de Meia-Idade , Força Muscular/fisiologia , Músculos Respiratórios/fisiopatologia , Testes de Função Respiratória , Diafragma/fisiopatologia , Idoso , Adulto
17.
Ying Yong Sheng Tai Xue Bao ; 35(6): 1501-1508, 2024 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-39235007

RESUMO

We conducted in a common garden experiment to explore the differences in soil enzyme activity, stoichiometry, and their influencing factors among a secondary Castanopsis carlesii forest, 10-year-old C. carlesii plantation, and Cunninghamia lanceolata plantation. The results showed that compared to the secondary forest, the soil organic carbon, total nitrogen, and dissolved organic carbon significantly decreased by 42.6%, 47.4%, and 60.9% in C. carlesii plantation, and by 42.9%, 36.7%, and 61.1% in C. lanceolata plantation. Soil microbial biomass C, microbial biomass N (MBN), and microbial biomass phosphorus decreased significantly by 40.6%, 35.5%, and 45.9% in C. carlesii plantation, and by 53.7%、56.4%, and 61.7% in C. lanceolata plantation. Compared to the secondary forest, soil enzymes activities in C. carlesii plantation did not change significantly, but in C. lanceolata plantation, the activities of ß-1,4-glucosidase and cellobiohydrolase significantly decreased by 51.2% and 59.8%, ß-N-acetyl glucosaminidase and acid phosphatase decreased significantly by 41.0% and 29.8%, and enzymatic C:N acquisition ratio and enzymatic C:P acquisition ratio significantly decreased by 11.3% and 7.7%, respectively. Results of redundancy analysis indicated that MBN and NO3--N were the primary factors influencing soil enzyme activity and enzymic stoichiometry. Collectively, there were significant differences in soil enzyme activity and microbial nutrient demands among different forest stands. Compared to secondary forests, the establishment of C. lanceolata plantations would intensify nutrient competition between plants and microbes, and exacerbate the N and P limitations for microbes.


Assuntos
Carbono , Cunninghamia , Florestas , Nitrogênio , Microbiologia do Solo , Solo , Solo/química , Nitrogênio/análise , Nitrogênio/metabolismo , China , Cunninghamia/crescimento & desenvolvimento , Carbono/análise , Fósforo/análise , Fósforo/metabolismo , Clima Tropical , Fagaceae/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Ecossistema
18.
Sci Rep ; 14(1): 20499, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227377

RESUMO

Imaging the internal architecture of fast-vibrating structures at micrometer scale and kilohertz frequencies poses great challenges for numerous applications, including the study of biological oscillators, mechanical testing of materials, and process engineering. Over the past decade, X-ray microtomography with retrospective gating has shown very promising advances in meeting these challenges. However, breakthroughs are still expected in acquisition and reconstruction procedures to keep improving the spatiotemporal resolution, and study the mechanics of fast-vibrating multiscale structures. Thereby, this works aims to improve this imaging technique by minimising streaking and motion blur artefacts through the optimisation of experimental parameters. For that purpose, we have coupled a numerical approach relying on tomography simulation with vibrating particles with known and ideal 3D geometry (micro-spheres or fibres) with experimental campaigns. These were carried out on soft composites, imaged in synchrotron X-ray beamlines while oscillating up to 400 Hz, thanks to a custom-developed vibromechanical device. This approach yields homogeneous angular sampling of projections and gives reliable predictions of image quality degradation due to motion blur. By overcoming several technical and scientific barriers limiting the feasibility and reproducibility of such investigations, we provide guidelines to enhance gated-CT 4D imaging for the analysis of heterogeneous, high-frequency oscillating materials.

19.
Water Res ; 266: 122375, 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39260194

RESUMO

Frequent occurrence of trace antibiotics in reclaimed water is concerning, which inevitably causes aquifer contamination in the case of managed aquifer recharge (MAR). Global governments have formulated strict reclaimed water standards to ensure the safety of water reuse. Recent studies have found that improved antibiotics removal is intimately associated with high ammonia-oxidizing activity. However, the role of NH4+-N in the removal of residual antibiotics of reclaimed water during MAR remains unknown. NH4+-N removal and the effects of ammonia oxidation on antibiotics biodegradation in the aquifer are the most significant facts for solving the above collision. In this work, the effects of NH4+-N (0, 1 and 5 mg/L) in a model refractory antibiotic (oxacillin (OXA), 100 µg/L) attenuation were deciphered by employing three individual simulated MAR columns, which so called N0, N1 and N5. The results showed that 5 mg/L NH4+-N in influent upregulated the abundance of amo genes by 28.9 %-68.0 % in N5. And the enriched functional genes encoding key degradation enzymes enhanced the OXA removal by 18.7 % and alleviated the oxidative stress caused by antibiotics. Subsequently, antibiotic resistance genes (ARGs), mobile gene elements (MGEs) and human bacterial pathogens (HBPs) abundance were all significantly decreased. Moreover, the intimate association between ammonia-oxidizing microorganisms (AOM) and candidate OXA degraders based on microbial network analysis further supported the significance of AOM on OXA biodegradation. This study provides comprehensive evidence that appropriate amounts of NH4+-N are beneficial in antibiotics and antibiotic resistance risk reduction, providing compelling insights for refine NH4+-N recharge limitation.

20.
Can J Occup Ther ; : 84174241255472, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39285696

RESUMO

Background. Limited knowledge is available regarding the impact of oculopharyngeal muscular dystrophy (OPMD) impairments on participation in daily and social activities, which currently hinders occupational therapy practice in this population. Purpose. To describe social participation and explore influencing factors in individuals with OPMD. Methods. Thirty-four individuals were assessed with outcome measures of social participation restrictions, mobility, dysphagia, and fatigue. Spearman correlations and stepwise multiple regression analyses were used. Findings. Results show a negative impact of OPMD on the social participation level, which was more important in participants aged over 60 years. Walking speed was found to be the main factor influencing participation levels for daily and social activities, with faster walking associated with higher participation. Conclusions. This study emphasizes the impact of OPMD impairments and limitations on social participation level. While dysphagia is obviously an important impairment to consider, interventions for mobility limitations should also be considered during clinical follow-up.

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