Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
Mais filtros












Base de dados
Intervalo de ano de publicação
1.
3D Print Addit Manuf ; 11(3): e1235-e1245, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-39359606

RESUMO

Structural hierarchy is the key to manufacturing multiscale particle-based composite materials. A novel manufacturing method was developed to generate scalable hierarchical structures in concrete. The new method used 3D-printed microscaffolds to interact with the multiscale particle packing in concrete, resulting in a structured lightweight composite material. The size of internal members can vary by more than two orders of magnitude, to adapt to different applications. Based on compression tests and microstructural investigation by optical microscope and quantitative nanomechanical mapping, we found that the new material is 63.93% more efficient in energy absorption capacity compared with traditional lightweight concrete. Our experimental trials also showed that introducing structural hierarchy can reduce the consumption of cementitious material in the system by up to 14% and significantly reduce the use of scaffolds. The method could be applied to a board spectrum of multiscale particle-based materials, such as dental cement and bone implant materials, to improve material performance and efficiency in medical and construction applications.

2.
Water Res ; 266: 122398, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39244865

RESUMO

Chemical moderate preoxidation for algae-laden water is an economical and prospective strategy for controlling algae and exogenous pollutants, whereas it is constrained by a lack of effective on-line evaluation and quick-response feedback method. Herein, excitation-emission matrix parallel factor analysis (EEM-PARAFAC) was used to identify cyanobacteria fluorophores after preoxidation of sodium hypochlorite (NaClO) at Excitation/Emission wavelength of 260(360)/450 nm, based on which the algal cell integrity and intracellular organic matter (IOM) release were quantitatively assessed. Machine learning modeling of fluorescence spectral data for prediction of moderate preoxidation using NaClO was established. The optimal NaClO dosage for moderate preoxidation depended on algal density, growth phases, and organic matter concentrations in source water matrices. Low doses of NaClO (<0.5 mg/L) led to short-term desorption of surface-adsorbed organic matter (S-AOM) without compromising algal cell integrity, whereas high doses of NaClO (≥0.5 mg/L) quickly caused cell damage. The optimal NaClO dosage increased from 0.2-0.3 mg/L to 0.9-1.2 mg/L, corresponding to the source water with algal densities from 0.1 × 106 to 2.0 × 106 cells/mL. Different growth stages required varying NaClO doses: stationary phase cells needed 0.3-0.5 mg/L, log phase cells 0.6-0.8 mg/L, and decaying cells 2.0-2.5 mg/L. The presence of natural organic matter and S-AOM increased the NaClO dosage limit with higher dissolved organic carbon (DOC) concentrations (1.00 mg/L DOC required 0.8-1.0 mg/L NaClO, while 2.20 mg/L DOC required 1.5-2.0 mg/L). Compared to other predictive models, the machine learning model (Gaussian process regression-Matern (0.5)) performed best, achieving R2 values of 1.000 and 0.976 in training and testing sets. Optimal preoxidation followed by coagulation effectively removed algal contaminants, achieving 91%, 92%, and 92% removal for algal cells, turbidity, and chlorophyll-a, respectively, thereby demonstrating the effectiveness of moderate preoxidation. This study introduces a novel approach to dynamically adjust NaClO dosage by monitoring source water qualities and tracking post-preoxidation fluorophores, enhancing moderate preoxidation technology application in algae-laden water treatment.

3.
J Glaucoma ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39283689

RESUMO

PRCIS: This research presents the burden and clinical characteristics of NVG in Zhongshan Ophthalmic Center, employing the most extensive sample size and the longest uninterrupted temporal duration so far, which may provide a theoretical reference for the effective prevention and diagnosis of NVG. PURPOSE: To summarize the burden and clinical characteristics of neovascular glaucoma (NVG) in a major tertiary care center in China. METHODS: The clinical data of NVG patients in Zhongshan Ophthalmic Center (ZOC) between 2012 and 2021 were collected retrospectively, including their age, sex, affected eye, best-corrected visual acuity (BCVA), intraocular pressure (IOP), clinical stage and aetiology. RESULTS: In this study, we included 1877 eyes of 1749 patients who developed NVG, with 2.01:1 ratio of male to female. Their mean age was 53.14±16.69 years and those aged 41-70 years (65.2%) were most affected. Monocular patients were more predominant in most of them (92.7%), while 7.3% were binocular and 1667 eyes (88.8%) were at the angle­closure stage. The BCVA and IOP were 2.42±0.70 logMAR and 38.6±12.2 mmHg, respectively. Over the decade, the number of NVG patients and the proportion of NVG patients among glaucoma patients showed an increasing trend, with annual percentage changes (APCs) of 9.1% (95% CI: 5.0-13.3%, P=0.001) and 4.8% (95% CI: 2.2-7.4%, P=0.003), respectively. The top three primary conditions were diabetic retinopathy (DR), retinal vein occlusion (RVO), and retinal detachment (RD). Moreover, the APCs for the constituent ratio of DR and RVO were 4.4% (95% CI: 0.5-8.4%, P=0.031) and ï¹£4.6% (95% CI: ï¹£8.4% to ï¹£0.7%, P=0.028), respectively. However, the first and second causes of NVG in minors (<18 years old) were Coat's disease and ocular tumours, followed by RD and RVO in third place. The top cause of NVG in patients aged 65 years and older was RVO. CONCLUSIONS: The burden of NVG is increasing, emphasizing the need to improve preventive strategies focusing on primary diseases such as DR, RVO, and RD, particularly the increasing proportion of DR cases and the previously underemphasized RD patients, while also highlighting the differences in primary diseases across different age groups.

4.
Water Res ; 266: 122432, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39298900

RESUMO

Evaporation has been one of the most classic desalination processes on the Earth. When we try to use the power of water flow itself, the evaporation process can perform even better. Here, we report a hydrodynamic solar-driven interfacial evaporation process which water evaporation rate can achieve 6.58 kg·m-2·h-1 (over 100 times higher than natural evaporation). A waterwheel-structure solar interfacial evaporator was designed and assembled by printed filter papers. The evaporator can both rapidly distribute solution on the evaporation interface and be hydraulically driven to rotate continuously to improve the evaporation rate by water flow. The hydrodynamic solar-driven interfacial evaporation process successfully overcomes the problem of slow diffusion of water vapor, but also realizes the day-and-night operation of process and the self-cleaning of salt fouling. Apart from the application in solar desalination, the developed evaporator has great potentials in vapor production and salt recovery for industrial use.

5.
PLoS One ; 19(9): e0309989, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39302933

RESUMO

Considering the peculiar socio-cultural background and developmental obstacles encountered by rural youth in China, the study examines the necessity of adopting an integrated strategy that brings together social work, psychology, and education to promote positive youth development. This research intends to fill the gap by explaining the impact of these factors on community engagement and youth development in China. Targeted programs were also suggested according to the needs of rural youth in China. The respondents of the study comprised 350 young people, whose age ranged from 15 to 24 years, living in different rural areas of the country. The structured questionnaire was designed to collect the data using a convenience sampling technique. Structural Equation Modeling (SEM) was applied as the analysis tool using IBM SPSS AMOS software. The results show that social work and education have a significant impact on community engagement and positive youth development. The findings also reveal that psychology positively influences community engagement. Community engagement was seen to mediate the relationships between social work, psychology, education, and positive youth development. The policymakers and practitioners can fully use the interrelationships between social work, psychology, and education to create a more comprehensive approach that considers the specific characteristics of rural youth in China. Additionally, highlighting community engagement as a mediator also explores the opportunity for bottom-up initiatives and community efforts to instigate favorable youth outcomes in the countryside.


Assuntos
População Rural , Serviço Social , Humanos , Adolescente , Masculino , Feminino , China , Adulto Jovem , Inquéritos e Questionários , Psicologia , Adulto , Desenvolvimento do Adolescente
6.
Materials (Basel) ; 17(16)2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39203246

RESUMO

A novel stress suppression design for flexible RF MEMS switches has been presented and demonstrated through theoretical and experimental research to isolate the stress caused by substrate bending. An RF MEMS switch with an S-shaped microspring structure was fabricated by the two-step etching process as a developmental step toward miniaturization and high reliability. The RF MEMS switches with an S-shaped microspring exhibited superior microwave performance and stable driving voltage under different substrate curvatures compared to the conventional non-microspring switches, demonstrating that the bending stress is successfully suppressed by the S-shaped microspring and the island structure. Furthermore, this innovative design could be easily extended to other flexible devices.

7.
Artigo em Inglês | MEDLINE | ID: mdl-39190516

RESUMO

Image- and video-based 3D human recovery (i.e., pose and shape estimation) have achieved substantial progress. However, due to the prohibitive cost of motion capture, existing datasets are often limited in scale and diversity. In this work, we obtain massive human sequences by playing the video game with automatically annotated 3D ground truths. Specifically, we contribute GTA-Human, a large-scale 3D human dataset generated with the GTA-V game engine, featuring a highly diverse set of subjects, actions, and scenarios. More importantly, we study the use of game-playing data and obtain five major insights. First, game-playing data is surprisingly effective. A simple frame-based baseline trained on GTA-Human outperforms more sophisticated methods by a large margin. For videobased methods, GTA-Human is even on par with the in-domain training set. Second, we discover that synthetic data provides critical complements to the real data that is typically collected indoor. We highlight that our investigation into domain gap provides explanations for our data mixture strategies that are simple yet useful, which offers new insights to the research community. Third, the scale of the dataset matters. The performance boost is closely related to the additional data available. A systematic study on multiple key factors (such as camera angle and body pose) reveals that the model performance is sensitive to data density. Fourth, the effectiveness of GTA-Human is also attributed to the rich collection of strong supervision labels (SMPL parameters), which are otherwise expensive to acquire in real datasets. Fifth, the benefits of synthetic data extend to larger models such as deeper convolutional neural networks (CNNs) and Transformers, for which a significant impact is also observed. We hope our work could pave the way for scaling up 3D human recovery to the real world. Homepage: https://caizhongang.github.io/projects/GTA-Human/.

8.
J Acoust Soc Am ; 156(1): 299-313, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38984811

RESUMO

Underwater acoustic target recognition based on passive sonar faces numerous challenges in practical maritime applications. One of the main challenges lies in the susceptibility of signal characteristics to diverse environmental conditions and data acquisition configurations, which can lead to instability in recognition systems. While significant efforts have been dedicated to addressing these influential factors in other domains of underwater acoustics, they are often neglected in the field of underwater acoustic target recognition. To overcome this limitation, this study designs auxiliary tasks that model influential factors (e.g., source range, water column depth, or wind speed) based on available annotations and adopts a multi-task framework to connect these factors to the recognition task. Furthermore, we integrate an adversarial learning mechanism into the multi-task framework to prompt the model to extract representations that are robust against influential factors. Through extensive experiments and analyses on the ShipsEar dataset, our proposed adversarial multi-task model demonstrates its capacity to effectively model the influential factors and achieve state-of-the-art performance on the 12-class recognition task.

9.
J Acoust Soc Am ; 156(1): 244-255, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38980097

RESUMO

Underwater acoustic target recognition has emerged as a prominent research area within the field of underwater acoustics. However, the current availability of authentic underwater acoustic signal recordings remains limited, which hinders data-driven acoustic recognition models from learning robust patterns of targets from a limited set of intricate underwater signals, thereby compromising their stability in practical applications. To overcome these limitations, this study proposes a recognition framework called M3 (multitask, multi-gate, multi-expert) to enhance the model's ability to capture robust patterns by making it aware of the inherent properties of targets. In this framework, an auxiliary task that focuses on target properties, such as estimating target size, is designed. The auxiliary task then shares parameters with the recognition task to realize multitask learning. This paradigm allows the model to concentrate on shared information across tasks and identify robust patterns of targets in a regularized manner, thus, enhancing the model's generalization ability. Moreover, M3 incorporates multi-expert and multi-gate mechanisms, allowing for the allocation of distinct parameter spaces to various underwater signals. This enables the model to process intricate signal patterns in a fine-grained and differentiated manner. To evaluate the effectiveness of M3, extensive experiments were implemented on the ShipsEar underwater ship-radiated noise dataset. The results substantiate that M3 has the ability to outperform the most advanced single-task recognition models, thereby achieving the state-of-the-art performance.

10.
Appl Opt ; 63(12): 3108-3116, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856454

RESUMO

In general, visible light communication (VLC) uses LEDs as transmitters. However, LEDs can serve as receivers to construct a simple duplex VLC system that uses only two LEDs instead of one LED and one photo-diode (PD). There is a lack of effective equivalent analysis models for characterizing and evaluating the inherent behavioral characteristics of LEDs used as receivers. This paper presents an equivalent analysis model for GaN LEDs as receivers. First, based on the proposed receiving equivalent circuit model, a third-order signal transmission mathematical analysis model is established, revealing the transmission relationship between the photocurrent and output voltage. Further research is conducted on the impact of parameter changes on the bandwidth, and the model can be simplified into a first-order low-pass mathematical analysis model under specific conditions, providing theoretical support for improving the bandwidth of LED receiving applications. The experimental results also confirm the theoretical predictions. This research result holds significant importance for revealing the intrinsic mechanisms and the improved optical communication performance of LEDs for effective reception.

11.
Adv Sci (Weinh) ; 11(26): e2401322, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38704683

RESUMO

Recent advances in solar-driven interfacial evaporation (SDIE) have led to high evaporation rates that open promising avenues for practical utilization in freshwater production and industrial application for pollutant and nutrient concentration, and resource recovery. Breakthroughs in overcoming the theoretical limitation of 2D interfacial evaporation have allowed for developing systems with high evaporation rates. This study presents a comprehensive review of various evaporator designs that have achieved pure evaporation rates beyond 4 kg m-2 h-1, including structural and material designs allowing for rapid evaporation, passive 3D designs, and systems coupled with alternative energy sources of wind and joule heating. The operational mechanisms for each design are outlined together with discussion on the current benefits and areas for improvement. The overarching challenges encountered by SDIE concerning the feasibility of direct integration into contemporary practical settings are assessed, and issues relating to sustaining elevated evaporation rates under diverse environmental conditions are addressed.

12.
Front Bioeng Biotechnol ; 12: 1303670, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38390364

RESUMO

Antibiotics are an important pharmaceutical class excessively used by humans. Its presence in the soil can impact plant growth and induce antibiotic resistance. This research studies the effect of sulfamethoxazole (SMX) on plant growth, rhizosphere bacteria composition, and resistance genes. Two sets of vegetables (basil, cilantro, and spinach) were treated separately with water and SMX solution. The plant growth data and soil samples were collected and analyzed. The results revealed that SMX increased spinach leaf length (34.0%) while having no significant impacts on basil and cilantro. On the other hand, SMX improved the bacterial diversity in all samples. The shifts in the abundance of plant growth-promoting bacteria could indirectly affect vegetable stem and leaf length. SMX also significantly increased the abundance of resistance genes Sul1 and Sul2. A further study into the correlation between bacteria highlights the importance of Shingomonas and Alfipia for inhibiting the spread of key resistance gene hosts, namely, Pseudomonas, Stenotrophomonas, and Agrobacterium. This research provides insight into SMX's impact on vegetable growth and microbial diversity. It also points out important microbial interactions that could potentially be utilized to mitigate ARG proliferation.

13.
BMC Surg ; 24(1): 41, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38297255

RESUMO

OBJECTIVE: Sciatic scoliosis can be seen in patients with lumbar disc herniation. Percutaneous endoscopic lumbar discectomy (PELD) is a common surgical method for the treatment of lumbar disc herniation. The difference between single-segment lumbar disc herniation and double-segment lumbar disc herniation with Sciatic Scoliosis in adults after PELD needs further study. The aim of this study was to compare the imaging features of single-segment and double-segment lumbar disc herniation with Sciatic Scoliosis in adults and to further explore the clinical outcomes of functional improvement and scoliosis imaging parameters of the two groups after PELD. METHODS: Adult patients with lumbar disc herniation with sciatic scoliosis who received PELD from January 2019 to June 2022 were analyzed retrospectively. According to the number of operative segments, the patients were divided into a single-segment group and a double-segment group. Perioperative parameters were observed and compared between the two groups. The Visual Analogue Scale (VAS) score, Oswestry dysfunction index (ODI), Japanese Orthopaedic Association scores (JOA) and imaging parameters of the two groups were recorded and compared before the operation and during the follow-up. RESULTS: A total of 53 patients with single segments and 21 patients with double segments were included in this study. During the follow-up, the VAS score, ODI index and JOA score of the two groups were significantly improved as compared with those before the operation(P < 0. 05). Ninety-two point five percent of single-segment patients and 90.5% of double segment patients returned to normal scoliosis within 12 months after the operation. The operation time, number of intraoperative fluoroscopy times and the amount of intraoperative blood loss in single-segment patients were better than those in double-segment group(P < 0. 05). At the last follow-up, the AVT, CBD and SVA in the double-segment group were 5.2 ± 2.3, 5.1 ± 1.0 and 12.2 ± 3.0 mm, respectively, which were higher than those in the single-segment group (1.9 ± 0.4, 1.1 ± 1.6 and 3.9 ± 2.1 mm) (P < 0. 05). CONCLUSION: PELD is an effective treatment for single-segment and double-segment lumbar disc herniation with Sciatic scoliosis. Double-segment patients can enjoy similar clinical efficacy to single-segment patients, avoiding complications caused by decompression, fusion, and internal fixation. Scoliosis was corrected spontaneously within 12 months after operation, and the sagittal curve was significantly improved in both groups. The improvement of coronal and sagittal balance in double -segment patients may take longer.


Assuntos
Discotomia Percutânea , Deslocamento do Disco Intervertebral , Escoliose , Adulto , Humanos , Deslocamento do Disco Intervertebral/complicações , Deslocamento do Disco Intervertebral/cirurgia , Estudos Retrospectivos , Discotomia Percutânea/métodos , Escoliose/complicações , Escoliose/cirurgia , Endoscopia/métodos , Vértebras Lombares/cirurgia , Discotomia/métodos , Resultado do Tratamento
14.
Sci Rep ; 13(1): 16027, 2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37749178

RESUMO

This study aimed to develop a physiologically-based pharmacokinetic (PBPK) model to predict the maximum plasma concentration (Cmax) and trough concentration (Ctrough) at steady-state of olaparib (OLA) in Caucasian, Japanese and Chinese. Furthermore, the PBPK model was combined with mean and 95% confidence interval to predict optimal dosing regimens of OLA when co-administered with CYP3A4 modulators and administered to patients with hepatic/renal impairment. The dosing regimens were determined based on safety and efficacy PK threshold Cmax (< 12,500 ng/mL) and Ctrough (772-2500 ng/mL). The population PBPK model for OLA was successfully developed and validated, demonstrating good consistency with clinically observed data. The ratios of predicted to observed values for Cmax and Ctrough fell within the range of 0.5 to 2.0. When OLA was co-administered with a strong or moderate CYP3A4 inhibitor, the recommended dosing regimens should be reduced to 100 mg BID and 150 mg BID, respectively. Additionally, the PBPK model also suggested that OLA could be not recommended with a strong or moderate CYP3A4 inducer. For patients with moderate hepatic and renal impairment, the dosing regimens of OLA were recommended to be reduced to 200 mg BID and 150 mg BID, respectively. In cases of severe hepatic and renal impairment, the PBPK model suggested a dosing regimen of 100 mg BID for OLA. Overall, this present PBPK model can determine the optimal dosing regimens for various clinical scenarios involving OLA.


Assuntos
Hepatopatias , Insuficiência Renal , Humanos , Citocromo P-450 CYP3A , Rim
15.
Heart Lung ; 61: 127-135, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37263145

RESUMO

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a common disease in intensive critical care(ICU), and the use of positive end-expiratory pressure(PEEP) during mechanical ventilation can increase the right heart afterload and eventually cause right heart dysfunction. For these factors causing acute cor pulmonale(ACP), especially inappropriate mechanical ventilation settings, it is important to explore the effect of PEEP on right heart function. OBJECTIVE: To investigate the effects of three titration methods on right heart function and prognosis in patients with ARDS. METHODS: Observational, prospective study in which ARDS patients were enrolled into three distinct PEEP-titration strategies groups: guide, transpulmonary pressure-oriented and driving pressure-oriented. Prognostic indicators, right heart systolic and diastolic echocardiographic function indices, ventilatory parameters, blood gas analysis results, and respiratory mechanics Monitoring indices were collated and analyzed statistically by STATA 15 software. RESULTS: A total of 62 ARDS patients were enrolled into guide (G) group (n=40) for whom titrated PEEP values were 9±2cm H2O, driving pressure-oriented (DPO) group (n=12) with titrated PEEP values of 10±2cm H2O and transpulmonary pressure-oriented (TPO) group (n=10) with titrated PEEP values of 12±3cm H2O. Values were significantly higher for TPO than for G (p=0.616) or DPO (p=0.011). Compliance was significantly increased after 72 h in the TPO and DPO groups compared with the G group (p<0.001). Mean airway pressure at end-inspiratory obstruction (p=0.047), tricuspid annular plane systolic excursion (TAPSE, p<0.001) and right ventricular area change fraction (RVFAC, p=0.049) were all higher in the TPO and DPO groups than in the G group. E/A indices were significantly better in the TPO group than in the G or DPO groups (p=0.046). No significant differences in 28 day mortality were found among the three groups. Multivariate logistic regression analysis revealed that lung compliance and transpulmonary pressure-oriented PEEP titration method was negatively correlated to the increase in right ventricular systolic dysfunction. CONCLUSION: Transpulmonary pressure-oriented PEEP titration improves oxygenation and pulmonary function and causes less right heart strain when compared to other PEEP-titration methods during mechanical ventilation of ARDS patients.


Assuntos
Síndrome do Desconforto Respiratório , Humanos , Estudos Prospectivos , Síndrome do Desconforto Respiratório/terapia , Pulmão , Respiração com Pressão Positiva/métodos , Prognóstico
16.
Environ Technol ; : 1-13, 2023 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-37337954

RESUMO

Natural organic matter (NOM) can impede the removal of organic micro-pollutants (OMPs) through several mechanisms, including inner filter effect, competition with the target OMP, and radical scavenging, during synchronous adsorption/photocatalysis of multi-functional composites. In this study, the fate and inhibitory mechanisms of sulfamerazine (SMZ, a model OMP) that occurred in presence of seven different NOM samples (i.e. three standard NOM surrogates, a river water sample, a carbon filter effluent and two different sand filter effluents) during the adsorption/photocatalysis by a composite of Bi2O3-TiO2 supported on powdered activated carbon (Bi2O3-TiO2/PAC, abbreviated as BTP) when exposed to visible light irradiation were revealed. The results indicated that adsorption played a greater attribution than photocatalysis on SMZ removal. The primary impediment to the adsorption and photocatalytic degradation of SMZ was attributed to the presence of terrestrial-derived, humic-like NOM fractions with high aromaticity. The adsorption efficacy of SMZ was weakened by the absorption of NOM and its degradation products onto the BTP surface. The inner filter effect, competition between NOM and SMZ, and radical scavenging were responsible for the reduced photocatalysis of SMZ. In the cases of real water matrices, the presence of inorganic anion and co-existed NOM reduced the removal of SMZ. In summary, the findings of this work offer a comprehensive comprehension of the impact of NOM fractions on photocatalysis, emphasizing the necessity to examine the interplay between NOM and background inorganic constituents in the degradation of OMP via adsorption/photocatalysis.

17.
Sci Total Environ ; 883: 163732, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37116799

RESUMO

The hyporheic zone, i.e. the groundwater-surface water interface within riverine/riparian ecosystems, plays a key role in water transport, energy flow and biogeochemical cycling at watershed scales. Water and heat exchange are fundamental processes regulating biogeochemical cycles in the hyporheic zones. To improve the understanding of hyporheic flow and heat transport in meandering streams, high-resolution measurements of water level and temperature, combined with a 3-D coupled model of flow and heat transport in the hyporheic zone of a meandering bend, were carried out during a summer flood season. Results show the distinct spatio-temporal variations of hyporheic water and heat exchange. Flooding events (the incoming flood water generated by the upstream rainfall) and local rainstorm events (the storm or rainfall occurring over the local study area) are major drivers for the coupled processes. Incoming flooding from the upper stream increases the hyporheic water and heat exchange in the riverbed and inner bank leading to the longer intra-meander residence times, and warms the riverbed and riverbanks due to the post-rainfall thermal recovery. Local rainstorm event increases hyporheic water and heat exchange flux both laterally and vertically and cools down the riverbed and riverbanks. The water exchange and thermal regimes in the intra-meander seems more driven by the local exchange flows, while the counterparts in the outer bank are dominated by the regional groundwater flow. The temperatures in the inner banks are 1 to 3 °C higher than those in the outer banks, indicating the better hydrological connectivity between river water and groundwater in the intra-meander. The meander apex is a hot spot for hyporheic water and heat exchange. The results highlight the close coupling among river morphology, hyporheic flow, and thermal heterogeneity in a meander system.

18.
Ophthalmol Ther ; 12(3): 1723-1735, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37027100

RESUMO

INTRODUCTION: Bleb scarring is the most important complication of trabeculectomy. Changing the application position of mitomycin C (MMC) during trabeculectomy might affect the surgery outcome. Our aim is to compare the effectiveness and safety of intraocular pressure (IOP) lowering in two different application sites of mitomycin in trabeculectomy. METHODS: This retrospective trial compared the surgical outcomes of 177 eyes that underwent trabeculectomy with adjunctive mitomycin C. In 70 eyes, an MMC-soaked sponge was applied under the scleral flap without touching Tenon's capsule. In 107 eyes, an MMC-soaked sponge was applied under the scleral flap covered by Tenon's capsule. Outcome measures were the IOP, best-corrected visual acuity (BCVA), success rates, and incidence of complications. RESULTS: Within both groups, a highly significant IOP reduction was seen during follow-up. The effectiveness in reducing IOP and the change in best-corrected visual acuity (BCVA) were similar between the two groups. Thin-walled blebs and postoperative hypotony were seen more often when MMC-soaked sponges were applied under the scleral flap covered by Tenon's capsule (P = 0.008 and P = 0.012, respectively). There was no significant difference in BCVA or other complications in either group. CONCLUSION: Since the effectiveness of IOP reduction was similar between both groups and with a low incidence of thin-walled blebs and hypotony, the subscleral application without touching Tenon's capsule seems to be the safer application site of MMC during trabeculectomy.

19.
Shanghai Kou Qiang Yi Xue ; 32(1): 97-100, 2023 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-36973852

RESUMO

PURPOSE: To investigate the application value of nitrous oxide/oxygen inhalation comfort technique during tooth extraction in elderly patients with hypertension under electrocardiographic(ECG) monitoring. METHODS: According to the inclusion and exclusion criteria, sixty elderly patients (over 65 years old) with hypertension for tooth extraction were randomly divided into 2 groups: the experimental group(nitrous oxide/oxygen inhalation combined with ECG monitoring group, n=30) and the control group (routine ECG monitoring group, n=30). Mean arterial pressure (MAP) and heart rate (HR) at T0 (baseline values before surgery), T1 (on local anesthesia), T2 (during operation) and T3(5 minutes after operation) were recorded. SPSS 25.0 software package was used for statistical analysis. RESULTS: There was no significant difference in MAP and HR at each time point in the experimental group(P>0.05). There was no significant difference in MAP and HR at T0 and T3 time points in the control group(P>0.05). At other time points, MAP and HR were significantly different (P<0.05). There was no significant differences in MAP and HR between the two groups at T0 and T3(P>0.05). MAP and HR at T1 and T2 in the experimental group were significantly less than those in the control group(P<0.05). CONCLUSIONS: Nitrous oxide/oxygen inhalation comfort technology can stabilize patients' emotions and maintain stable blood pressure and heart rate in elderly patients with hypertension during tooth extraction, thus improving the safety of tooth extraction.


Assuntos
Hipertensão , Óxido Nitroso , Humanos , Idoso , Óxido Nitroso/efeitos adversos , Oxigênio , Extração Dentária/efeitos adversos , Assistência Odontológica
20.
J Hazard Mater ; 449: 131065, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36840988

RESUMO

The physicochemical properties of powdered activated carbon (PAC) are important factors affecting its adsorption performance, which is also related to the characteristics of target organic pollutants. In this study, the key indicators affecting the adsorption performance of PAC were identified, and the physicochemical properties of PACs were modified by hydrogen peroxide and/or ultrasound in a targeted manner to improve the adsorption performance. The results indicated the adsorption properties of printing and dyeing secondary effluent organic matter (EfOM) in terms of CODcr and UV absorbance at 254 nm (UV254) positively correlated with mesoporous volume, average pore size and acid group content of PAC. After modification, the mesoporous volume and average pore size of PAC increased, and the number of acidic groups increased, thus enhancing the adsorption efficiency. EfOM removal characteristics showed that PAC preferentially adsorbed unsaturated bonds or aromatic compounds, tryptophan-like proteins, soluble microbial metabolites and low molecular weight fractions below 1 kDa. In addition, the relative contents of specific surface area, pore volume and oxygen-containing functional groups (O-CO, C-OH, CO/O-C-O) of PAC decreased after adsorption, indicating that EfOM adsorption was a physical and chemical process, including pore filling, hydrophobic interaction and chemical bond force interaction. In general, PACs with larger mesoporous volume, average pore size and abundant acid groups possessed good adsorption performance towards EfOM.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...