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1.
Sci Rep ; 14(1): 21422, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39271715

RESUMEN

A large-scale, high-speed, long-runout landslide occurred in Xinmo Village, Maoxian, Sichuan Province, China, on June 24, 2017. It was characterized by fast sliding speed, rapid volume growth, and large impact area. The dynamic process of such landslides and the influence of erosion on the dynamic process are studied by field investigation, numerical inversion and simulation. The results showed that entrainment erosion was a major factor of landslide volumetric change and a salient feature of the landslide process. An exponential equation relating the erosion rate and the deposition volume was established. Moreover, the study found that a slight change of the erosion rate (1e-4) also had a significant impact on the lateral spreading, longitudinal runout, and vertical erosion. As the erosion rate increased, the lateral spreading, longitudinal runout, and vertical erosion of this type of landslide became more obvious. By using the coefficient of variation method, it was obtained that the erosion rate had a greater influence on the vertical erosion than on the lateral spreading and longitudinal runout. In the study of the velocity of the rock avalanche under different erosion conditions, it was found that the erosion amount and the landslide velocity were not strictly linearly related. This study has important significance for understanding the dynamic process and erosion effect of rock avalanche, and provides useful references and insights for future research in related fields.

2.
BMC Oral Health ; 24(1): 1082, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39272108

RESUMEN

BACKGROUND: Erosive tooth wear is an increasingly common pathology in the youth population. It refers to the chronic, localized, painless loss of dental hard tissues caused by non-bacterial acids, often originating from external sources like acidic beverages. Energy drink consumption is on the rise, frequently preceding physical exercise to enhance perceived energy levels. However, there are other types of beverages that also provide energy, such as pre-workout drinks, classified as sports drinks. The main objective of this research study has been conducted with the purpose of analyzing the pH of energy drinks and pre-workout beverages, and studying the frequency of consumption of such beverages in amateur athletes who practice sports. METHODS: A total of 67 beverages were examined, comprising 43 energy drinks and 24 sports supplementation beverages, also known as pre-workout or pre-training beverages. The participants were given a survey to complete. They were asked to respond whether they consumed any type of pre-workout or energy drink, and they were also asked about the timing of consumption. RESULTS: The findings indicated an average pH of 3.3 among the studied beverages, indicating a pH below the critical threshold. Out of the 113 participants, 51% reported taking some form of supplementation. CONCLUSIONS: Consequently, it was concluded that most of the analyzed beverages recorded pH values low enough to classify them as erosive, posing a threat to enamel surface. When analyzing the frequency of consumption of energy drinks and pre-workout beverages in amateur athletes, we observed that most participants aged 29 years or younger took supplements 3 to 5 times a week, while the older age groups more frequently took supplements 1 to 2 times a week.


Asunto(s)
Bebidas Energéticas , Humanos , Concentración de Iones de Hidrógeno , Bebidas Energéticas/estadística & datos numéricos , Estudios Transversales , Masculino , Femenino , Adulto Joven , Adulto , Bebidas , Adolescente , Erosión de los Dientes/etiología
3.
Sci Total Environ ; 953: 176162, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39260505

RESUMEN

Climate factors and changes in landscape patterns are often recognized as the primary drivers of soil conservation services. The influence mechanism of climate factors and landscape patterns on soil conservation service is scale-dependent and spatial heterogeneous. However, it is not clear whether small watershed scale is more conducive to soil erosion control than large scale such as county scale and township scale. For the purpose of creating land use development plans that take local conditions into account, it is crucial to clarify the effects of climate and landscape pattern factors on soil conservation change. Wujiang River basin (WRB), a typical karst basin located in the catchment of the largest first-level tributary on the upper Yangtze River in China, was used as the study area in this research. Soil conservation services provided by water erosion control (SPC) in WRB from 2005 to 2020 were evaluated using the RUSLE model based on the modified rock exposure rate. By using stepwise regression model and multi-scale geographically weighted regression model (MGWR), the spatial heterogeneity of the influence of different driving factors on soil conservation service was comprehensively studied at the scale of district, township and small watershed. The results show that the SPC fluctuates obviously, but the trend is not significant. Climate factor is the dominant factor affecting SPC. With the change of scale from large to small, the adjusted R2 of the regression model gradually increases, especially the factors related to landscape pattern, and more driving factors can be revealed more comprehensively and effectively. Therefore, the small watershed scale is the best control unit to improve the SPC when formulating the regional management landscape plan. The findings of this research also have benchmark significance for other ecological fragile areas, and can provide more comprehensive suggestions for local ecosystem management and landscape planning.

4.
Materials (Basel) ; 17(17)2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39274569

RESUMEN

Laser beam remelting is a relatively simple and highly effective technique for the physical modification of surfaces to improve resistance to cavitation erosion. In this study, we investigated the effect of laser remelting on the surface of cast stainless steel with 0.40% C, 25% Cr, 20% Ni, and 1.5% Si on cavitation erosion behavior in tap water. The investigation was conducted using a piezoceramic crystal vibrator apparatus. Base laser beam parameters were carefully selected to result in a defect-free surface (no porosity, material burn, cracks) with hardness capable of generating better resistance to cavitation erosion. The experimental results were compared with those of the reference material. Surface morphology and microstructure evolution after cavitation tests were analyzed using an optical metallographic microscope (OM), scanning electron microscope (SEM), and hardness tests to explore the mechanism of improving surface degradation resistance. The conducted research demonstrated that surfaces modified by laser remelting exhibit a 4.8-5.1 times greater increase in cavitation erosion resistance due to the homogenization of chemical composition and refinement of the microstructure, while maintaining the properties of the base material.

5.
Materials (Basel) ; 17(17)2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39274668

RESUMEN

The erosion of surface pipelines induced by proppant flowback during shale gas production is significant. The surface pipelines in a shale gas field in the Sichuan Basin experienced perforation failures after only five months of service. To investigate the erosion features of L360N, coatings, and ceramics and optimize the selection of two protective materials, a gas-solid two-phase flow jet erosion experimental device was used to explore the erosion resistance of L360N, coatings, and ceramics under different impact velocities (15 m/s, 20 m/s, and 30 m/s). An energy dispersive spectroscope, a scanning electron microscope, and a laser confocal microscope were employed to analyze erosion morphologies. With the increase in flow velocity, the erosion depth and erosion rate of L360N, coating, and ceramic increased and peaked under an impact velocity of 30 m/s. The maximum erosion rate and maximum erosion depth of L360N were, respectively, 0.0350 mg/g and 37.5365 µm. Its primary material removal mechanism was the plowing of solid particles, and microcracks were distributed on the material surface under high flow velocities. The maximum erosion rate and maximum erosion depth of the coating were, respectively, 0.0217 mg/g and 18.9964 µm. The detachment of matrix caused by plowing is the main material removal mechanism. The maximum erosion rate and maximum erosion depth of ceramics were, respectively, 0.0108 mg/g and 12.4856 µm. The erosion mechanisms were micro-cutting and plowing. Under different particle impact velocities, different erosion morphologies were observed, but the primary erosion mechanism was the same. The erosion resistance of the ceramics was higher than that of the coatings. Therefore, ceramic lining materials could be used to protect the easily eroded parts, such as pipeline bends and tees, and reduce the failure rate by more than 93%. The study provided the data and theoretical basis for the theoretical study on oil and gas pipeline erosion and pipeline material selection.

6.
Materials (Basel) ; 17(17)2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39274786

RESUMEN

The erosion process of a 4 µm monolayer CrN coating deposited on 316L stainless steel due to cavitation was investigated using finite element analysis (FEA). To estimate load parameters from cavitation pit geometry resulting from high impact velocity and high strain rate, the explicit dynamic solver was employed. Water microjet impacts at velocities of 100, 200 and 500 m/s were simulated to recreate different cavitation erosion intensities observed in the experiment. The resulting damage characteristics were compared to previous studies on uncoated 316L steel. The relationship between impact velocity and postimpact geometry was examined. Simulations revealed that only impact at 500 m/s can exceed the maximum yield stress of the substrate without penetrating the coating. Subsequent impacts on the same zone deepen the impact pit and penetrate the coating, leading to direct substrate degradation. The influence of impact velocity on the coating degradation process is discussed.

7.
J Environ Manage ; 370: 122540, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39303588

RESUMEN

Effective regulation of land-use activities in steepland areas is crucial to protect downstream ecologies and human life as intense rainfall disturbances become more frequent globally. In Aotearoa New Zealand extensive synchronous clear-cutting of Pinus radiata monocultures on steep convergent landforms, and associated earthworks, causes ongoing accelerated erosion, excessive sedimentation, and debris-laden landslides after adverse weather events. This study examines the implementation of national forestry regulations established in 2018, which also enable regional councils to create more stringent rules to protect aquatic ecosystems. All sixteen councils were surveyed in 2021 and 2022 for stringency in planning provisions; and four regions seriously affected by Cyclone Gabrielle in 2023 were resurveyed in 2024. The cyclone caused loss of human life and calamitous damage to housing, infrastructure, and productive land uses from floods exacerbated by clearcut logging debris. All councils had administratively adopted the national regulations into their existing freshwater and coastal resource management plans. Twelve councils retained existing rules that conflicted with the regulations, but these rules do not protect all regionally significant aquatic ecosystems nor minimise landslide risks. No council, except Gisborne, had instigated the expensive and lengthy statutory resource management plan change process, nor taken a 'strategic and principled' approach to develop more stringent regulations, such as tougher restrictions on clear-cutting, earthworks, and replanting on steep erosion-prone convergent landforms to protect aquatic ecosystems and vulnerable communities. The government did tighten the management of logging debris after the cyclone, but the national regulations remain ineffective in addressing clear-cut practices maladaptive to intense rainfall and continue to permit replanting on convergent landforms. The regulations need urgent amendment to require councils to develop and implement a strategic and principled approach to stringency to better protect aquatic ecosystems, human life, economic livelihoods, and public infrastructure. Water quality monitoring is also currently inadequate, as no council systematically monitors the effects of forestry activities on sedimentation rates, which inhibits the ability to compare across and between regions. Foresters are not required to monitor water quality, which also stymies assessments of compliance and policy effectiveness. Councils regularly monitor rivers, lakes, and estuaries, but rarely the effects of individual land uses. This means that sediment or other contaminants cannot be parsed to different land use activities, undermining attempts to set catchment limits. It can also take decades at current monitoring levels to defensibly show any water quality improvements after changes to land use regulations. The current environmental limits approach of setting individual water quality attribute targets is highly unlikely to drive changes to maladaptive and ecologically degrading land uses. A new environmental management approach is needed that prohibits or effectively constrains hazardous and adverse activities.

8.
Heliyon ; 10(17): e37448, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39296146

RESUMEN

Bank erosion is a key feature of channel evolution in alluvial rivers, and will occur under the combined effect of hydraulic erosion and frost heave/freeze-thaw process of rivers in seasonal frozen regions. However, most research on bank erosion modeling has seldom considered the impact of the frost heave/freeze-thaw process. Therefore, the variation in the mechanical characteristics of riverbank soil under the freeze-thaw cycle was investigated firstly in the current research and then used in the modeling of bank erosion processes at typical sections of the Songhua River. Additionally, a sensitivity analysis of riverbank stability was conducted using orthogonal experiments. The results indicate that after 7 freeze-thaw cycles, the soil cohesion and internal friction angle of bank soil decreased by about 10%-47 % and 9%-19 %, respectively. Unlike lowland rivers, bank erosion of rivers in seasonal frozen regions is more likely to occur during the rising water period. The frost heaving/freeze-thaw process will make the bank stability safety coefficient Fs more quickly decrease to the unstable critical value. As compared with the case without considering the frost heaving/freeze-thaw process, the mass failure occurred in advance when the frost heaving/freeze-thaw process was considered, and the calculated bank erosion volume was increased by 11%-51 %, agreeing better with the measured value. The sensitivity ranking of the four influencing factors on riverbank stability under freezing-thawing conditions is as follows: river stage > groundwater level > cohesion > internal friction angle. The current study can provide a reference for research on bank erosion and channel evolution of rivers in seasonal frozen regions.

9.
Cureus ; 16(8): e67367, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39310649

RESUMEN

Background Endotracheal tube (ETT) cuff pressure changes during general anesthesia. Endotracheal cuff pressure ideally should be maintained between 20 and 30 cm of H2O. Cuff pressure of less than 25 cm of H2O increases the chances of aspiration while pressure of more than 40 cm of H2O causes tracheal mucosa damage. The study aimed to monitor and compare variations of endotracheal cuff pressure during general anesthesia with oxygen-air or oxygen-nitrous oxide. Methods This prospective, randomized, double-blinded, observational study was conducted on 40 patients. After approval from the institutional ethics subcommittee, 40 patients of either gender, aged 18-60 years, belonging to ASA grades I and II, who were undergoing elective surgery under general anesthesia, were enrolled in this study. The patients were randomly divided into two groups, with 20 in each group. In Group A, oxygen-air and Group N, oxygen-nitrous oxide was used as a gaseous mixture in general anesthesia with ETT. The ETT cuff pressure was recorded with the help of a cuff manometer at intervals of five, 10, 20, 30, 40, 50, 60, 70, 80, and 90 minutes after intubation. If pressure was more than 40 cm of H2O, it was reduced to 25-30 cm of H2O. Data were collected and analyzed using methods described in Primer of Biostatistics by Stanton A. Glantz. Quantitative data were analyzed using the Student's t-test. Qualitative data were analyzed using the chi-square test. Results An increase in cuff pressure was noted more in Group N as compared to Group A. The pressure in the endotracheal cuff started to gradually increase after 30-40 minutes in Group N after intubation, while in Group A, there was no significant increase. The average number of times the cuff deflated was 0.2 ± 0.41 in Group A and 1.55 ± 0.51 in Group N, which was highly significant. Conclusion Changes in endotracheal cuff pressure were observed when using different gas mixtures for inflation. Specifically, cuff pressure increased with oxygen and nitrous oxide compared to oxygen with air. This suggests that anesthetic gas composition can impact cuff pressure, potentially affecting tracheal mucosal perfusion and patient safety. Therefore, regular monitoring and adjustment of cuff pressure is crucial, especially when using nitrous oxide, to prevent complications and ensure optimal patient care.

10.
Artículo en Inglés | MEDLINE | ID: mdl-39298030

RESUMEN

Soil erosion poses significant ecological and socioeconomic challenges, driven by factors such as inappropriate land use, extreme rainfall events, deforestation, farming methods, and climate change. This study focuses on the Kozhikode district in Kerala, South India, which has seen increased vulnerability to soil erosion due to its unique geographical characteristics, increase in extreme events, and recent land use trends. The research employs RUSLE (Revised Universal Soil Loss Equation), considering multiple contributing factors such as rainfall erosivity (R), slope length and steepness (LS), cover management (C), conservation practices (P), and soil erodibility (K). The study is unique and novel, since it integrates extensive field data collected from agricultural plots across Kozhikode with the RUSLE model predictions, providing a more accurate and context-specific understanding of soil erosion processes and also suggesting management strategies based on risk priority. The study found that Kozhikode experiences an average annual soil loss of 28.7 tons per hectare. A spatial analysis revealed varying erosion risk levels across the district. 52.0% of the area experiences very slight erosion, 10.31% has slight erosion, 6.18% undergoes moderate erosion, 3.88% is moderately severe, 7.34% is at severe erosion risk, 5.6% has very severe erosion, and 14.65% faces extremely severe erosion. Field data collected from agricultural plots across Kozhikode were compared with RUSLE-predicted values, revealing a low root mean square error, indicating a strong correlation between observed and simulated data. Based on these findings, the district was categorized into low, medium, and high-priority regions, with tailored recommendations proposed for each. Implementing these measures could mitigate erosion, preserve soil fertility, and support the long-term sustainability of natural and agricultural ecosystems in Kozhikode. Given the practical challenges in estimating RUSLE factors in Southern India, where data scarcity is a common issue, this preliminary study underscores the need for expanded, long-term field observations to enhance understanding of soil erosion processes at the watershed level.

11.
Sci Rep ; 14(1): 21955, 2024 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-39304695

RESUMEN

Lishu County, which is located in the black soil region of Northeast China, represents a key site for the analysis of soil erosion intensity. This study offers a scientific foundation for the development of targeted soil and water conservation strategies within the region. The Revised Universal Soil Loss Equation (RUSLE) was employed to compute the soil erosion modulus in Lishu County, with the objective of conducting a quantitative analysis of the temporal and spatial distribution patterns of soil erosion. Additionally, the changing characteristics of soil erosion were examined from the perspectives of land use types and slope variations. The Generalized Connectivity Causality Model (GCCM) was utilized to identify the causal relationship between soil erosion and land use types through the reconstruction of state space and cross-mapping predictions. (1) Soil erosion in Lishu County between 2000 and 2020 predominantly exhibited mild to moderate levels, characterized by patchy and sporadic erosion, with relatively severe occurrences in the northern and central regions. (2) Soil erosion was correlated with land use and slope variations, with more than 90% of erosion incidents transpiring in cultivated land areas. The 3°-5° slope range in Lishu County emerged as a focal point for erosion, necessitating targeted prevention and control measures. (3) The GCCM model illustrated a discernible causal relationship between soil erosion and land use, revealing mutual influences between the two factors. Between 2000 and 2020, both the area and intensity of soil erosion in Lishu County exhibited an initial increase, followed by a subsequent decrease. This suggests an overall trend of amelioration in soil erosion conditions. However, notable spatial disparities persist in the erosion distribution across the region.

12.
Heliyon ; 10(16): e35813, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39220909

RESUMEN

Microbial-induced calcite precipitation (MICP) is an environmentally friendly process that can be used to enhance soil surface stability against wind erosion. In this study, the performance of the MICP process on soil surface improvement was investigated using Staphylococcus warneri IR-103 bacteria. The biostabilizer, containing S. warneri suspension and a cementation solution consisting of 0.5 mM CaCl2 and 1.5 mM urea, was sprayed on fine-grain soil to induce a surface MICP reaction. Soil surface strength was measured using a penetrometer test, and wind tunnel tests were conducted to evaluate the soil surface's resistance to wind erosion. Scanning electron microscopy (SEM) analysis of the treated soils was conducted to visualize carbonate crystal formations within and on the soil particles. Additionally, X-ray diffraction (XRD) was used to confirm the presence and identify the crystal structures. The ecotoxicological assessment of the biostabilizer was carried out by performing phytotoxicity and oral/dermal/ocular in vivo acute toxicity experiments due to a few case reports of S. warneri's harmfulness and virulence of coagulase-negative staphylococci, highlighting the need for safety measures for workers and end-users. Mixing cementation solution with bacterial suspension in yeast-ammonium chloride medium increased soil strength and durability. The biostabilizer did not harm the seed germination of Agropyron desertorum, and the soil surface remained resistant to wind erosion. Rat oral/dermal acute toxicity tests revealed no adverse effects during the 14-day observation period. The LD50 (median lethal dose) cut-off value of the biostabilizer in oral and dermal administrations was 5000 and 1000 mg/kg body weight, respectively. Ocular administration of a 0.1 mL drop did not induce eye irritation in rabbits. In conclusion, the use of the biostabilizer for wind erosion control appears to be technically and environmentally feasible and justifiable.

13.
Ying Yong Sheng Tai Xue Bao ; 35(7): 1815-1824, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39233410

RESUMEN

Exploring the physical fractions of organic carbon and influencing mechanisms in grassland, forest, and farmland soils in wind erosion area can provide scientific basis for carbon sequestration, land utilization, wind prevention measure making, and fertility restoration of sloping farmland in the region. We examined the differentiation of aggregate organic carbon and density fractionation organic carbon in 0-15 cm soil layer across grassland, forest, and sloping farmland with 350 m long and 5° slope gradient in the wind erosion area of Meilisi District, Qiqihar, Heilongjiang, as well as the sloping farmland in the downhill section, middle section, and uphill section with every 100 m apart from the bottom to the top. The results showed that soil aggregates >2 mm were all destroyed across grassland, forest, and farmland soils, while the percentage of aggregates <0.053 mm was significantly higher than that of other sizes. The percentage of various soil aggregates, organic carbon content from density fractionations, and the proportion of organic carbon in the heavy fraction aggregates in farmland were significantly lower than that in grassland and forest soils. Soil aggregates in the uphill section of farmland were completely destroyed, and organic carbon content in various size aggregates and density fractionations gradually decreased with increasing slope. The proportion of organic carbon in the heavy fraction aggregates decreased, but that in light fraction aggregates increased gradually. Soil organic carbon and available potassium were key factors affecting aggregate stability, aggregate organic carbon content, and organic carbon content in density fractionations, while the loss of organic carbon in aggregate led to a decrease in aggregate stability. In summary, compared with grassland and forest soils, the stability of soil aggregates, the aggregate organic carbon content, the organic carbon content in density fractionations, and the proportion of organic carbon in heavy fraction aggregates in farmland all decreased in the wind erosion area of Northeast China. With the increases of slope, the aggregate organic carbon content, the organic carbon content in density fractionations, and the proportion of organic carbon in the heavy fraction aggregates in sloping farmland all decreased. Planting trees, conserving and expanding grassland area, and increasing the application of organic materials in sloping farmland in wind erosion area are effective approaches to stabilize and increase carbon storage, improve soil structure, and enhance soil quality.


Asunto(s)
Carbono , Compuestos Orgánicos , Suelo , Viento , China , Carbono/análisis , Carbono/química , Suelo/química , Compuestos Orgánicos/análisis , Productos Agrícolas/crecimiento & desarrollo , Pradera , Erosión del Suelo , Bosques , Árboles/crecimiento & desarrollo , Poaceae/crecimiento & desarrollo , Conservación de los Recursos Naturales , Ecosistema
14.
Data Brief ; 55: 110685, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39234062

RESUMEN

This dataset quantifies storm intensity of approximately 130 unique historical storms along the New Jersey coastline from 1980 to 2014 for three separate sea level conditions. Namely, (1) as observed in the historical record; (2) detrended to 1997 mean sea level and (3) adjusted to the 2050 and 2100 sea level rise scenarios presented in the International Panel on Climate Change's (IPCC) Sixth Assessment Report (AR6). Projected sea level scenarios are adjusted to include local vertical land movement. Storm intensity is quantified in terms of erosion potential, considering the combination of total water level, wave heights, and storm duration. The observational dataset includes both tropical and extratropical storms and quantifies both the cumulative (duration) and peak (single hour) storm intensity for each storm and sea level rise (SLR) condition. Additionally, hourly time series of wave characteristics and water levels are provided at 13 locations along the New Jersey coast, facilitating hydrodynamic forcing of nearshore models. The dataset provides the means and methods to directly compare historical storms under future SLR conditions.

15.
Sci Total Environ ; 954: 176259, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39276994

RESUMEN

The Laptev Sea (LS) and Western East Siberian Sea (W-ESS) are paradigmatic examples of seas dominated by terrestrial organic matter, attributed to substantial Siberian River discharges and coastal erosion. The influx of terrestrial organic matter significantly alters the biochemical composition of particulate organic matter (POM) in these Arctic coastal regions, potentially reducing the nutritional quality available to higher trophic levels. This study investigated the origin and qualitative characteristics of POM in the LS and W-ESS during the late summer of 2018 by analyzing elemental ratios (C/N ratio), stable carbon isotopes (δ13C), and biochemical compositions (biomolecular and amino acid (AA) compositions). The conspicuously depleted δ13C values (mean ± standard deviation (SD) = -30.2 ± 0.5 ‰) and alongside elevated molar C/N ratios (mean ± SD = 18.1 ± 6.2) suggest that terrestrial organic matter is the predominant source of POM in the study area. Although carbohydrates (CHO) were the dominant biomolecules, their prevalence was higher in the river-influenced W-ESS region (67.7 ± 6.6 %) than in the LS region (58.6 ± 13.9 %; p < 0.05). Furthermore, the CHO composition was closely associated with freshwater content and river fraction, suggesting that the heightened contribution of CHO may stem from terrestrial organic matter delivered by river inputs. Lower concentrations of particulate hydrolyzable AA (PAA) and carbon and nitrogen normalized yields of AAs (AA-POC% and AA-PON%) along with reduced contribution of glycine suggested a substantial contribution of terrestrial POM to both LS and W-ESS POM. Overall, this study provides valuable insights into the terrestrial influence on POM composition in Arctic marine ecosystems, emphasizing the need for continued monitoring of the consequences of terrestrial carbon inputs in the changing Arctic environment.

16.
Artículo en Inglés | MEDLINE | ID: mdl-39288322

RESUMEN

OBJECTIVES: To evaluate whether inhibition of Janus kinases (JAK) 1 could lead to erosion repair on high-resolution peripheral quantitative computer tomography (HR-pQCT) in patients with active rheumatoid arthritis (RA). METHODS: This was a prospective, non-randomized pilot study. We enrolled 20 adult patients with active RA with ≥1 bone erosion on HR-pQCT. They were given upadacitinib 15 mg once daily for 24 weeks. HR-pQCT of the metacarpophalangeal joint was performed at baseline and 24-week. The serum bone biomarkers level was evaluated before and after treatment. Twenty age-and-sex matched RA patients from another study treated with conventional synthetic disease modifying anti-rheumatic drugs (csDMARDs) were included as active controls. RESULTS: Nineteen patients in the upadacitinib group completed the study procedures. After 24 weeks, despite similar improvement in disease activity, a reversed trend in the mean erosion volume change on HR-pQCT was observed comparing the upadacitinib and active control group (upadacitinib group: -0.23 ± 3.26mm3 vs control group: 1.32 ± 6.05mm3, p= 0.131). A greater proportion of erosions in the upadacitinib group demonstrated regression (27% vs 12%, p= 0.085). Using general estimating equation (GEE), the use of upadacitinib was significantly associated with erosion regression (OR: 3.61, 95% CI: 1.00-13.00, p= 0.049) after adjusting for the difference in disease duration. The serum levels of bone resorption markers reduced after upadacitinib treatment. No new safety signal was noted. CONCLUSION: Despite a similar improvement in RA disease activity after upadacitinib compared with csDMARDs, a differential regression of erosion on HR-pQCT was observed in patients received upadacitinib. The potential role of JAK1 inhibition in erosion repair should be investigated.

17.
Sci Total Environ ; : 176257, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39288874

RESUMEN

Beach erosion is an adverse impact of climate change and human development activities. Effective beach management necessitates integrating natural and anthropogenic factors to address future erosion trends, while most current prediction models focus only on natural factors, which may provide an incomplete and potentially inaccurate representation of erosion dynamics. This study enhances prediction methods by integrating both natural and anthropogenic factors, thereby enhancing the accuracy and reliability of erosion projections. By extracting historical shorelines through CoastSat model from 1986 to 2020, we develop multivariable scenarios with Attention-LSTM model to predict the regional impacts of natural and anthropogenic factors on erosion to sandy beaches along the typical shoreline of Shenzhen in China. Results reveal that Shenzhen's beaches experienced erosion up to 12 m over the past 35 years. Here we project a decrease in the mean erosion rate of the beaches, identifying population growth (21.0 %) as the main controlling factor before the mid-century in a range of scenarios. We find that Attention-LSTM multi-model ensemble approach can provide overall improved accuracy and reliability over a wide range of beach erosion compared to scenario prediction model of Attention-LSTM and statistical model of Digital Shoreline Analysis System (DSAS), yielding an average uncertainty of 10.99 compared to 13.29. These insights reveal policies to safeguard beaches because of the rising demand for beaches due to human factors, coupled with decreased impervious surfaces through ecological conservation, lead to mitigation for beach erosion. Accurate forecasts empower policymakers to implement effective coastal management strategies, safeguard resources, and mitigate erosion's adverse effects. Our study offers finely-tuned predictions of coastal erosion, providing crucial insights for future coastal conservation efforts and climate change adaptation along the shoreline, and serving as a foundation for further research aimed at understanding the evolving environmental impacts of beach erosion in Shenzhen.

18.
Sci Total Environ ; 954: 176211, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39277007

RESUMEN

Vegetation restoration is an effective and important measure for controlling soil erosion in arid and -arid regions. Both its aboveground and underground parts play a crucial role in controlling surface runoff and soil detachment on slopes. But how much the parts of vegetation contribute to the runoff and sediment reducing benefits of rill erosion on slopes is unclear. We used grassland slopes at four successional stages for simulated scouring experiments to observe how successional vegetation community structures, root characteristics, and soil structures contribute to erosion and sand production. Initial flow production time increased, and total runoff decreased. Under the scour intensities, the 11-year slope had the lowest flood peak and volume and the greatest runoff reduction benefit. The 25-year slope had the lowest sand peak and volume and the greatest sediment reduction benefit. As scour intensity increased, runoff reduction effect of vegetation at the successional stages decreased; the sediment reduction benefit remained high. PLS-PM analysis showed that the indirect effects of the aboveground and underground parts of vegetation on sand production were -0.364 and -0.439, respectively. Aboveground parts mainly embodied the regulation of runoff, in which stem count, humus mass, and biomass were the main factors affecting runoff and sand production. Underground parts mainly reflected their soil structure improvement, in which root volume density, root surface area density, and root mass density are the main explanatory variables. The direct effects of runoff and soil structure on slope rill erosion were 0.330 and -0.616, respectively, suggesting the stability of soil structure is the primary factor affecting the sand production, not erosion energy. The results provide a reference for scientific assessment of the key role of natural vegetation restoration in regional soil erosion control and the development of biological measures for soil and water conservation on the slopes of the Loess Plateau.

19.
Transl Androl Urol ; 13(8): 1717-1728, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39280683

RESUMEN

Iatrogenic stress urinary incontinence (SUI) is the most common complication of surgical treatment of prostate cancer, regardless of operative approach, and has a major impact on patients' quality of life. Although SUI can occur after surgical treatment of benign prostatic hyperplasia, specifically transurethral prostate resection, laser enucleation of the prostate, and simple open prostatectomy, these therapeutic modalities play a much less significant role in the etiology of SUI. Artificial urethral sphincter (AUS) implantation is considered the standard treatment modality providing high success rates, including durable efficacy, and optimal patient satisfaction for moderate to severe urinary incontinence resulting mainly from radical prostatectomy. However, although complication rates are generally acceptably low, revision and/or explantation may be required due to mechanical failure and non-mechanical problems, specifically urethral atrophy/cuff deficient occlusion, infection, and cuff erosion. Several risk factors for AUS failure associated with a fragile, compromised urethra have been identified and these play a critical role in device cuff erosion and subsequent removal of the device. Among others, apparently the most impacting factors are irradiation, urethral stent placement, a previous AUS placement, and importantly presence of urethral stricture or prior urethroplasty. Generally, any clinical situation leading to a diseased urethra or lack of urethral integrity is associated with impaired local blood perfusion, and consequently lower success rates. The present review aims to evaluate the impact of the presence of prior urethral strictures and urethroplasty on the outcomes of AUS implantation on one hand, and vice-versa, the influence of AUS placement on later urethral stricture surgery, particularly following cuff erosion.

20.
Am J Vet Res ; : 1-8, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39250933

RESUMEN

OBJECTIVE: To explain the relationship between cartilage erosion and medial patellar luxation (MPL) and to identify risk factors in dogs. METHODS: A retrospective review was conducted on 90 dogs (103 stifles) surgically treated for MPL between January 2006 and March 2024. Data collected included signalment, side of operated stifle, patellar luxation grade, symptom duration, and lameness score. Cartilage erosion was evaluated for extent and location on the patella and femoral trochlea. Statistical analyses were conducted to identify risk factors. RESULTS: The prevalence of cartilage erosion of the patella and femoral trochlea was 47.6% (49/103) and 54.4% (56/103), respectively, increasing with a higher grade of patellar luxation. Lesions were most prevalent in the distolateral patella and proximomedial trochlea, with generalized lesions more prevalent in grade IV. The extent of both lesions was significantly associated with age, patellar luxation grade, and symptom duration, while body weight significantly correlated only with the cartilage erosion of the patella. No significant correlation was observed with sex, side of operated stifle, or lameness score. CONCLUSIONS: Many patients with MPL exhibited cartilage erosion in the patellofemoral joint, likely due to biomechanical mechanisms. Surgery can be indicated for patients with MPL, as it may prevent cartilage erosion while improving patellofemoral alignment and gait. When selecting surgical candidates, it is important to consider risk factors, such as patellar luxation grade, body weight, age, and symptom duration. CLINICAL RELEVANCE: Early surgical treatment is recommended, especially for dogs with higher body weight and higher grade of MPL, to prevent cartilage erosion and secondary osteoarthritis.

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