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2.
PLoS One ; 19(5): e0301204, 2024.
Article En | MEDLINE | ID: mdl-38728281

Tidal bore impact can be strong and destructive, placing estuarine infrastructures under great threat. However, there is a lack of research focusing on accurately estimating the impact pressure exerted by tidal bores. Herein new experiments were conducted to investigate the pressure of tidal bore fronts in a glass flume. Through analysis of instantaneous pressure of three forms of tidal bore, it was observed that the pressure fluctuation of weak and strong breaking bore fronts is characterized by impact pressure. The vertical distribution and maximum impact pressure of tidal bore were studied.The maximum impact pressure of breaking bore fronts appeared around 0.46 times height of it. The relationship between relative impact pressure and height of the tidal bore fronts was found to closely follow a normal probability density function. Through nonlinear regression analysis, an empirical equation was derived to calculate impact pressure, which was validated using observation data from the Qiantang River in China. This equation can be utilized to predict the impact pressure of tidal bore fronts and provide valuable support for estuarine engineering design.


Pressure , China , Tidal Waves , Rivers , Estuaries , Models, Theoretical
3.
Int J Mol Sci ; 25(9)2024 Apr 24.
Article En | MEDLINE | ID: mdl-38731845

Moringa oleifera leaves are rich sources of bioactive compounds with potential health benefits, including antioxidants and anti-inflammatory agents. Pressurized liquid extraction (PLE) stands out as a promising technique for effectively extracting valuable compounds from natural sources. In this study, we aimed to optimize PLE parameters, such as temperature, extraction duration, and pressure, to maximize bioactive compound (polyphenols, flavonoids, and ascorbic acid) yield from M. oleifera leaves and evaluate their antioxidant and anti-inflammatory activities. According to the outcomes of this research, the maximum achieved total polyphenol content was 24.10 mg gallic acid equivalents (GAE)/g of dry weight (dw), and the total flavonoid content was increased up to 19.89 mg rutin equivalents (RtE)/g dw. Moreover, after HPLC-DAD analysis, neochlorogenic and chlorogenic acids, catechin and epicatechin, rutin, and narirutin were identified and quantified. As far as the optimum ascorbic acid content is concerned, it was found to be 4.77 mg/g dw. The antioxidant activity was evaluated by three different methods: ferric reducing antioxidant power (FRAP), the DPPH method, and the anti-hydrogen peroxide activity (AHPA) method, resulting in 124.29 µmol ascorbic acid equivalent (AAE)/g dw, 131.28 µmol AAE/g dw, and 229.38 µmol AAE/g dw values, respectively. Lastly, the albumin denaturation inhibition was found to be 37.54%. These findings underscore the potential of PLE as an efficient extraction method for preparing extracts from M. oleifera leaves with the maximum content of bioactive compounds.


Antioxidants , Moringa oleifera , Plant Extracts , Plant Leaves , Moringa oleifera/chemistry , Plant Leaves/chemistry , Antioxidants/pharmacology , Antioxidants/chemistry , Antioxidants/isolation & purification , Plant Extracts/pharmacology , Plant Extracts/chemistry , Flavonoids/isolation & purification , Flavonoids/analysis , Flavonoids/chemistry , Flavonoids/pharmacology , Polyphenols/isolation & purification , Polyphenols/pharmacology , Polyphenols/analysis , Polyphenols/chemistry , Ascorbic Acid/pharmacology , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/isolation & purification , Chromatography, High Pressure Liquid/methods , Pressure , Liquid-Liquid Extraction/methods , Phytochemicals/chemistry , Phytochemicals/pharmacology , Phytochemicals/isolation & purification
4.
PLoS One ; 19(5): e0300241, 2024.
Article En | MEDLINE | ID: mdl-38696384

OBJECTIVE: Technical ex-vivo comparison of commercial nebulizer nozzles used for Pressurized Intraperitoneal Aerosol Chemotherapy (PIPAC). METHODS: The performance of four different commercial nebulizer nozzles (Nebulizer; HurriChemTM; MCR-4 TOPOL®; QuattroJet) was analysed concerning: i) technical design and principle of operation, ii) operational pressure as function of the liquid flow rate, iii) droplet size distribution via laser diffraction spectrometry, iv) spray cone angle, spray cone form as well as horizontal drug deposition by image-metric analyses and v) chemical resistance via exposing to a cytostatic solution and chemical composition by means of spark optical emission spectral analysis. RESULTS: The Nebulizer shows quasi an identical technical design and thus also a similar performance (e.g., mass median droplet size of 29 µm) as the original PIPAC nozzles (MIP/ CapnoPen). All other nozzles show more or less a performance deviation to the original PIPAC nozzles. The HurriChemTM has a similar design and principle of operation as the Nebulizer, but provides a finer aerosol (22 µm). The principle of operation of MCR-4 TOPOL® and QuattroJet differ significantly from that of the original PIPAC nozzle technology. The MCR-4 TOPOL® offers a hollow spray cone with significantly larger droplets (50 µm) than the original PIPAC nozzles. The QuattroJet generates an aerosol (22 µm) similar to that of the HurriChemTM but with improved spatial drug distribution. CONCLUSION: The availability of new PIPAC nozzles is encouraging but can also have a negative impact if their performance and efficacy is unknown. It is recommended that PIPAC nozzles that deviate from the current standard should be subject to bioequivalence testing and implementation in accordance with the IDEAL-D framework prior to routine clinical use.


Aerosols , Nebulizers and Vaporizers , Humans , Antineoplastic Agents/administration & dosage , Pressure , Particle Size , Equipment Design
5.
Sci Rep ; 14(1): 11084, 2024 05 15.
Article En | MEDLINE | ID: mdl-38744916

In order to solve the difficult portability problem of traditional non-invasive sleeping posture recognition algorithms arising from the production cost and computational cost, this paper proposes a sleeping posture recognition model focusing on human body structural feature extraction and integration of feature space and algorithms based on a specific air-spring mattress structure, called SPR-DE (SPR-DE is the Sleep Posture Recognition-Data Ensemble acronym form). The model combines SMR (SMR stands for Principle of Spearman Maximal Relevance) with horizontal and vertical division based on the barometric pressure signals in the human body's backbone region to reconstruct the raw pressure data into strongly correlated non-image features of the sleep postures in different parts and directions and construct the feature set. Finally, the recognit-ion of the two sleep postures is accomplished using the AdaBoost-SVM integrated classifier. SPR-DE is compared with the base and integrated classifiers to verify its performance. The experimental results show that the amount of significant features helps the algorithm to classify different sleeping patterns more accurately, and the f1 score of the SPR-DE model determined by the comparison experiments is 0.998, and the accuracy can reach 99.9%. Compared with other models, the accuracy is improved by 2.9% ~ 7.7%, and the f1-score is improved by 0.029 ~ 0.076. Therefore, it is concluded that the SMR feature extraction strategy in the SPR-DE model and the AdaBoost-SVM can achieve high accuracy and strong robustness in the task of sleep posture recognition in a small area, low-density air-pressure mattress, taking into account the comfort of the mattress structural design and the sleep posture recognition, integrated with the mattress adaptive adjustment system.


Algorithms , Beds , Posture , Sleep , Humans , Posture/physiology , Sleep/physiology , Pressure , Male , Adult
6.
J Med Internet Res ; 26: e44948, 2024 May 08.
Article En | MEDLINE | ID: mdl-38718385

BACKGROUND: Monitoring of gait patterns by insoles is popular to study behavior and activity in the daily life of people and throughout the rehabilitation process of patients. Live data analyses may improve personalized prevention and treatment regimens, as well as rehabilitation. The M-shaped plantar pressure curve during the stance phase is mainly defined by the loading and unloading slope, 2 maxima, 1 minimum, as well as the force during defined periods. When monitoring gait continuously, walking uphill or downhill could affect this curve in characteristic ways. OBJECTIVE: For walking on a slope, typical changes in the stance phase curve measured by insoles were hypothesized. METHODS: In total, 40 healthy participants of both sexes were fitted with individually calibrated insoles with 16 pressure sensors each and a recording frequency of 100 Hz. Participants walked on a treadmill at 4 km/h for 1 minute in each of the following slopes: -20%, -15%, -10%, -5%, 0%, 5%, 10%, 15%, and 20%. Raw data were exported for analyses. A custom-developed data platform was used for data processing and parameter calculation, including step detection, data transformation, and normalization for time by natural cubic spline interpolation and force (proportion of body weight). To identify the time-axis positions of the desired maxima and minimum among the available extremum candidates in each step, a Gaussian filter was applied (σ=3, kernel size 7). Inconclusive extremum candidates were further processed by screening for time plausibility, maximum or minimum pool filtering, and monotony. Several parameters that describe the curve trajectory were computed for each step. The normal distribution of data was tested by the Kolmogorov-Smirnov and Shapiro-Wilk tests. RESULTS: Data were normally distributed. An analysis of variance with the gait parameters as dependent and slope as independent variables revealed significant changes related to the slope for the following parameters of the stance phase curve: the mean force during loading and unloading, the 2 maxima and the minimum, as well as the loading and unloading slope (all P<.001). A simultaneous increase in the loading slope, the first maximum and the mean loading force combined with a decrease in the mean unloading force, the second maximum, and the unloading slope is characteristic for downhill walking. The opposite represents uphill walking. The minimum had its peak at horizontal walking and values dropped when walking uphill and downhill alike. It is therefore not a suitable parameter to distinguish between uphill and downhill walking. CONCLUSIONS: While patient-related factors, such as anthropometrics, injury, or disease shape the stance phase curve on a longer-term scale, walking on slopes leads to temporary and characteristic short-term changes in the curve trajectory.


Foot , Gait , Pressure , Walking , Humans , Male , Female , Cross-Sectional Studies , Walking/physiology , Adult , Foot/physiology , Gait/physiology , Young Adult , Biomechanical Phenomena
7.
Scand Cardiovasc J ; 58(1): 2347295, 2024 Dec.
Article En | MEDLINE | ID: mdl-38706409

Objectives. This study investigated the influence of higher pressure protection with a small diameter balloon of side branch (SB) on bifurcation lesions. Background. Of the different coronary stent implantation techniques, the modified jailed balloon technique has become a viable option for bifurcation lesions. However, there was no detailed study on the relationship between the balloon inflation pressure of the main vessel (MV) and SB. Methods. In this study, we collected information of patients who underwent percutaneous coronary intervention (PCI) for bifurcated lesions between March 2019 and December 2022. They were divided into two groups according to the operation way: active jailed balloon technique (A-JBT) group and jailed wire technique (JWT) group. Results. A total of 216 patients were enrolled. The A-JBT group had a larger SB stenosis diameter (1.53 ± 0.69 vs. 0.95 ± 0.52, p < .001), the lower degree of stenosis (44.34 ± 18.30 vs. 63.69 ± 17.34, p < .001) compared to the JWT group. However, the JWT group had a higher incidence of SB occlusion (18.0% vs. 1.9%, p < .001) compared to the A-JBT group. Nevertheless, the success rate for both groups was 100%. Conclusions. This novel high inflation pressure and small diameter balloon approach we propose has significant advantages. There is a lower rate of SB occlusion and SB dissection, which is more cost-effective and provides better clinical outcomes for the patient. This method should be considered in the future for treating bifurcation lesions.


Angioplasty, Balloon, Coronary , Cardiac Catheters , Coronary Artery Disease , Humans , Male , Female , Aged , Middle Aged , Treatment Outcome , Coronary Artery Disease/therapy , Coronary Artery Disease/diagnostic imaging , Angioplasty, Balloon, Coronary/instrumentation , Angioplasty, Balloon, Coronary/adverse effects , Retrospective Studies , Stents , Coronary Stenosis/diagnostic imaging , Coronary Stenosis/therapy , Coronary Stenosis/surgery , Risk Factors , Pressure , Time Factors , Percutaneous Coronary Intervention/adverse effects , Percutaneous Coronary Intervention/instrumentation
8.
Opt Lett ; 49(9): 2341-2344, 2024 May 01.
Article En | MEDLINE | ID: mdl-38691714

In the fields of biomedicine and microfluidics, the non-contact capture, manipulation, and spin of micro-particles hold great importance. In this study, we propose a programmable non-contact manipulation technique that utilizes photoacoustic effect to spin and transport living shrimp eggs. By directing a modulated pulsed laser toward a liquid-covered stainless-steel membrane, we can excite patterned Lamb waves within the membrane. These Lamb waves occur at the interface between the membrane and the liquid, enabling the manipulation of nearby particles. Experimental results demonstrate the successful capture, spin, and transport of shrimp eggs in diameter of 220 µm over a distance of about 5 mm. Calculations indicate that the acoustic radiation force and torque generated by our photoacoustic manipulation system are more than 299.5 nN and 41.0 nN·mm, respectively. The system surpasses traditional optical tweezers in terms of force and traditional acoustic tweezers in terms of flexibility. Consequently, this non-contact manipulation system significantly expands the possibilities for applications in various fields, including embryo screening, cell manipulation, and microfluidics.


Ovum , Photoacoustic Techniques , Animals , Photoacoustic Techniques/methods , Pressure , Optical Tweezers , Penaeidae
9.
Med Eng Phys ; 127: 104168, 2024 May.
Article En | MEDLINE | ID: mdl-38692764

Skin color observation provides a simple and non-invasive method to estimate the health status of patients. Capillary Refill Time (CRT) is widely used as an indicator of pathophysiological conditions, especially in emergency patients. While the measurement of CRT is easy to perform, its evaluation is highly subjective. This study proposes a method to aid quantified CRT measurement using an RGB camera. The procedure consists in applying finger compression to the forearm, and the CRT is calculated based on the skin color change after the pressure release. We estimate compression applied by a finger from its fingernail color change during compression. Our study shows a step towards camera-based quantitative CRT for untrained individuals.


Capillaries , Fingers , Fingers/blood supply , Fingers/physiology , Humans , Capillaries/physiology , Capillaries/diagnostic imaging , Time Factors , Pressure , Male , Adult , Mechanical Phenomena , Female
10.
Sensors (Basel) ; 24(9)2024 Apr 23.
Article En | MEDLINE | ID: mdl-38732781

INTRODUCTION: Diabetic foot ulcers (DFU) are a devastating complication of diabetes. There are numerous challenges with preventing diabetic foot complications and barriers to achieving the care processes suggested in established foot care guidelines. Multi-faceted digital health solutions, which combine multimodal sensing, patient-facing biofeedback, and remote patient monitoring (RPM), show promise in improving our ability to understand, prevent, and manage DFUs. METHODS: Patients with a history of diabetic plantar foot ulcers were enrolled in a prospective cohort study and equipped with custom sensory insoles to track plantar pressure, plantar temperature, step count, and adherence data. Sensory insole data enabled patient-facing biofeedback to cue active plantar offloading in response to sustained high plantar pressures, and RPM assessments in response to data trends of concern in plantar pressure, plantar temperature, or sensory insole adherence. Three non-consecutive case participants that ultimately presented with pre-ulcerative lesions (a callus and/or erythematous area on the plantar surface of the foot) during the study were selected for this case series. RESULTS: Across three illustrative patients, continuous plantar pressure monitoring demonstrated promise for empowering both the patient and provider with information for data-driven management of pressure offloading treatments. CONCLUSION: Multi-faceted digital health solutions can naturally enable and reinforce the integrative foot care guidelines. Multi-modal sensing across multiple physiologic domains supports the monitoring of foot health at various stages along the DFU pathogenesis pathway. Furthermore, digital health solutions equipped with remote patient monitoring unlock new opportunities for personalizing treatments, providing periodic self-care reinforcement, and encouraging patient engagement-key tools for improving patient adherence to their diabetic foot care plan.


Diabetic Foot , Humans , Diabetic Foot/therapy , Male , Female , Middle Aged , Aged , Prospective Studies , Pressure , Monitoring, Physiologic/methods , Digital Health
11.
Sensors (Basel) ; 24(9)2024 May 06.
Article En | MEDLINE | ID: mdl-38733050

Gait phase monitoring wearable sensors play a crucial role in assessing both health and athletic performance, offering valuable insights into an individual's gait pattern. In this study, we introduced a simple and cost-effective capacitive gait sensor manufacturing approach, utilizing a micropatterned polydimethylsiloxane dielectric layer placed between screen-printed silver electrodes. The sensor demonstrated inherent stretchability and durability, even when the electrode was bent at a 45-degree angle, it maintained an electrode resistance of approximately 3 Ω. This feature is particularly advantageous for gait monitoring applications. Furthermore, the fabricated flexible capacitive pressure sensor exhibited higher sensitivity and linearity at both low and high pressure and displayed very good stability. Notably, the sensors demonstrated rapid response and recovery times for both under low and high pressure. To further explore the capabilities of these new sensors, they were successfully tested as insole-type pressure sensors for real-time gait signal monitoring. The sensors displayed a well-balanced combination of sensitivity and response time, making them well-suited for gait analysis. Beyond gait analysis, the proposed sensor holds the potential for a wide range of applications within biomedical, sports, and commercial systems where soft and conformable sensors are preferred.


Gait , Pressure , Wearable Electronic Devices , Wireless Technology , Humans , Gait/physiology , Wireless Technology/instrumentation , Gait Analysis/methods , Gait Analysis/instrumentation , Electrodes , Shoes , Equipment Design
12.
Biomacromolecules ; 25(5): 3018-3032, 2024 May 13.
Article En | MEDLINE | ID: mdl-38648261

Different cellulose nanocrystal (CNC) forms (dried vs never-dried) can lead to different degrees of CNC reassembly, the formation of nanofibril-like structures, in nanocomposite latex-based pressure-sensitive adhesive (PSA) formulations. CNC reassembly is also affected by CNC sonication and loading as well as the protocol used for CNC addition to the polymerization. In this study, carboxylated CNCs (cCNCs) were incorporated into a seeded, semibatch, 2-ethylhexyl acrylate/methyl methacrylate/styrene emulsion polymerization and cast as pressure-sensitive adhesive (PSA) films. The addition of CNCs led to a simultaneous increase in tack strength, peel strength, and shear adhesion, avoiding the typical trade-off between the adhesive and cohesive strength. Increased CNC reassembly resulted from the use of dried, redispersed, and sonicated cCNCs, along with increased cCNC loading and addition of the cCNCs at the seed stage of the polymerization. The increased degree of CNC reassembly was shown to significantly increase the shear adhesion by enhancing the elastic modulus of the PSA films.


Adhesives , Cellulose , Latex , Nanoparticles , Cellulose/chemistry , Adhesives/chemistry , Nanoparticles/chemistry , Latex/chemistry , Polymerization , Nanocomposites/chemistry , Pressure
13.
J Colloid Interface Sci ; 668: 142-153, 2024 Aug 15.
Article En | MEDLINE | ID: mdl-38669992

Based on real-time detection of plantar pressure, gait recognition could provide important health information for rehabilitation administration, fatigue prevention, and sports training assessment. So far, such researches are extremely limited due to lacking of reliable, stable and comfortable plantar pressure sensors. Herein, a strategy for preparing high compression strength and resilience conductive iongels has been proposed by implanting physically entangled polymer chains with covalently cross-linked networks. The resulting iongels have excellent mechanical properties including nice compliance (young's modulus < 300 kPa), high compression strength (>10 MPa at a strain of 90 %), and good resilience (self-recovery within seconds). And capacitive pressure sensor composed by them possesses excellent sensitivity, good linear response even under very small stress (∼kPa), and long-term durability (cycles > 100,000) under high-stress conditions (133 kPa). Then, capacitive pressure sensor arrays have been prepared for high-precision detection of plantar pressure spatial distribution, which also exhibit excellent sensing performances and long-term stability. Further, an extremely sensitive and fast response plantar pressure monitoring system has been designed for monitoring plantar pressure of foot at different postures including upright, forward and backward. The system achieves real-time tracking and monitoring of changes of plantar pressure during different static and dynamic posture processes. And the characteristics of plantar pressure information can be digitally and photography displayed. Finally, we propose an intelligent framework for real-time detection of plantar pressure by combining electronic insoles with data analysis system, which presents excellent applications in sport trainings and safety precautions.


Pressure , Humans , Electric Conductivity , Foot/physiology , Monitoring, Physiologic/instrumentation , Gait/physiology , Surface Properties , Wearable Electronic Devices
14.
Medicina (Kaunas) ; 60(4)2024 Apr 03.
Article En | MEDLINE | ID: mdl-38674236

Background and Objectives: Current evidence confirms that the magnitude of the inter-rectus distance (IRD) is associated with the severity of abdominal pain. Furthermore, evidence exists in the literature about the impact abdominal muscles have on low back pain, lumbopelvic pain, breathing and lumbar abdominal strength; however, no studies analysing the level of association between abdominal diastasis and lumbar pain pressure threshold (PPT) exist. The aim of this study was to analyse the level of association between the rectus abdominis distance and pain pressure threshold in the lumbar spinous processes in women who have given birth between the ages of 30 and 45 years. Secondly, it was to study the level of association between the time elapsed since the last delivery and low back pain in women who have given birth between 30 and 45 years of age. Material and Methods: This was a pilot observational study in which 21 females participated. The abdominal diastasis was measured by ultrasound, the pain pressure threshold was assessed by an algometer and the pain perception by the Mc Gill questionnaire. Results: There was no significant relationship between increased abdominal distance and increased lumbopelvic pain in women who gave birth between the ages of 30 and 45 years. However, there was a correlation between the time that had elapsed since the last delivery and low back pain. Conclusions: there was a correlation between the time that had elapsed since the last delivery and low back pain. Further studies analysing factors that may perpetuate the chronicity of symptoms, such as lifestyle and intrinsic factors, are needed.


Low Back Pain , Humans , Female , Pilot Projects , Adult , Low Back Pain/physiopathology , Middle Aged , Pain Threshold/physiology , Rectus Abdominis/physiopathology , Pain Measurement/methods , Diastasis, Muscle/physiopathology , Diastasis, Muscle/complications , Pressure , Surveys and Questionnaires , Lumbosacral Region/physiopathology
15.
Water Sci Technol ; 89(7): 1787-1806, 2024 Apr.
Article En | MEDLINE | ID: mdl-38619903

The conventional building drainage system was constructed based on the theory of two-phase flow involving water and air. However, the drainage system contained a more intricate three-phase flow, encompassing water, air, and solids, which was relatively overlooked in research. This study addressed the impact of solids on pressure fluctuations, air flow rates, and hydraulic jump fullness within the drainage system, considering three factors: the mass factor, cross-section factor, and viscosity. The investigation was conducted within a single-stack system using both experimental methods and CFD simulations. The findings revealed a positive correlation between both positive and negative pressures and above three factors. The mass factor and the cross-section factor had a more significant impact on the negative pressure of the system. The maximum growth rates of negative pressure extremes under different mass and cross-section factors reached 7.72 and 16.52%, respectively. In contrast, the viscosity of fecal sludge had a slightly higher effect on the positive pressure fluctuation of the drainage system, with the maximum growth rate of positive pressure extremes at 3.41%.


Sewage , Water , Air Pressure , Pressure , Viscosity
16.
Sensors (Basel) ; 24(8)2024 Apr 10.
Article En | MEDLINE | ID: mdl-38676030

Reducing high mechanical stress is imperative to heal diabetes-related foot ulcers. We explored the association of cumulative plantar tissue stress (CPTS) and plantar foot ulcer healing, and the feasibility of measuring CPTS, in two prospective cohort studies (Australia (AU) and The Netherlands (NL)). Both studies used multiple sensors to measure factors to determine CPTS: plantar pressures, weight-bearing activities, and adherence to offloading treatments, with thermal stress response also measured to estimate shear stress in the AU-study. The primary outcome was ulcer healing at 12 weeks. Twenty-five participants were recruited: 13 in the AU-study and 12 in the NL-study. CPTS data were complete for five participants (38%) at baseline and one (8%) during follow-up in the AU-study, and one (8%) at baseline and zero (0%) during follow-up in the NL-study. Reasons for low completion at baseline were technical issues (AU-study: 31%, NL-study: 50%), non-adherent participants (15% and 8%) or combinations (15% and 33%); and at follow-up refusal of participants (62% and 25%). These underpowered findings showed that CPTS was non-significantly lower in people who healed compared with non-healed people (457 [117; 727], 679 [312; 1327] MPa·s/day). Current feasibility of CPTS seems low, given technical challenges and non-adherence, which may reflect the burden of treating diabetes-related foot ulcers.


Diabetic Foot , Stress, Mechanical , Humans , Diabetic Foot/physiopathology , Female , Middle Aged , Male , Prospective Studies , Biomechanical Phenomena , Aged , Feasibility Studies , Foot/physiopathology , Wound Healing/physiology , Pressure
17.
Mar Pollut Bull ; 202: 116275, 2024 May.
Article En | MEDLINE | ID: mdl-38564821

Mesopelagic water from the deep Eastern Mediterranean Sea (EMS) was collected under disrupted (REPRESS) or undisturbed (HP) pressure conditions and was acclimated to oil (OIL) or dispersed-oil (DISPOIL) under in situ pressure and temperature (10 MPa, 14 °C). Decompression resulted in oil-acclimatised microbial communities of lower diversity despite the restoration of in situ pressure conditions during the 1-week incubation. Further biodiversity loss was observed when oil-acclimatised communities were transferred to ONR7 medium to facilitate the isolation of oil-degrading bacteria. Microbial diversity loss impacted the degradation of recalcitrant oil compounds, especially PAHs, as low-abundance taxa, linked with PAH degradation, were outcompeted in the enrichment process. Thalassomonas, Pseudoalteromonas, Halomonas and Alcanivorax were enriched in ONR7 under all experimental conditions. No effect of dispersant application on the microbial community structure was identified. A. venustensis was isolated under all tested conditions suggesting a potential key role of this species in hydrocarbons removal in the deep EMS.


Biodiversity , Microbiota , Petroleum , Mediterranean Sea , Microbiota/drug effects , Biodegradation, Environmental , Polycyclic Aromatic Hydrocarbons/analysis , Bacteria , Culture Media , Water Pollutants, Chemical , Seawater/microbiology , Seawater/chemistry , Pressure
18.
J R Soc Interface ; 21(213): 20230659, 2024 04.
Article En | MEDLINE | ID: mdl-38565158

The flow of cerebrospinal fluid (CSF) along perivascular spaces (PVSs) is an important part of the brain's system for clearing metabolic waste. Astrocyte endfeet bound the PVSs of penetrating arteries, separating them from brain extracellular space. Gaps between astrocyte endfeet might provide a low-resistance pathway for fluid transport across the wall. Recent studies suggest that the astrocyte endfeet function as valves that rectify the CSF flow, producing the net flow observed in pial PVSs by changing the size of the gaps in response to pressure changes. In this study, we quantify this rectification based on three features of the PVSs: the quasi-circular geometry, the deformable endfoot wall, and the pressure oscillation inside. We provide an analytical model, based on the thin-shell hoop-stress approximation, and predict a pumping efficiency of about 0.4, which would contribute significantly to the observed flow. When we add the flow resistance of the extracellular space (ECS) to the model, we find an increased net flow during sleep, due to the known increase in ECS porosity (decreased flow resistance) compared to that in the awake state. We corroborate our analytical model with three-dimensional fluid-solid interaction simulations.


Glymphatic System , Glymphatic System/physiology , Brain/blood supply , Arteries/physiology , Pressure , Biological Transport , Cerebrospinal Fluid/metabolism
19.
Spectrochim Acta A Mol Biomol Spectrosc ; 316: 124352, 2024 Aug 05.
Article En | MEDLINE | ID: mdl-38678841

Mucin 1 is an essential tumor biomarker, and developing cost-effective and portable methods for mucin 1 detection is crucial in resource-limited settings. Herein, the pH-regulated dual-enzyme mimic activities of manganese dioxide nanosheets were demonstrated, which were integrated into an aptasensor for dual-mode detection of mucin 1. Under acidic conditions, manganese dioxide nanosheets with oxidase mimic activities catalyzed the oxidation of 3,3',5,5'-tetramethylbenzidine sulfate, producing visible multicolor signals; while under basic conditions, manganese dioxide nanosheets with catalase mimic activities were used as catalyst for the decomposition of hydrogen peroxide, generating gas pressure signals. The proposed method allows the naked eye detection of mucin 1 through multicolor signal readout and the quantitative detection of mucin 1 with a handheld pressure meter or a UV-vis spectrophotometer. The study demonstrates that manganese dioxide nanosheets with pH-regulated dual-enzyme mimic activities can facilitate multidimensional transducing signals. The use of manganese dioxide nanosheets for the transduction of different signals avoids extra labels and simplifies the operation procedures. Besides, the signal readout mode can be selected according to the available detection instruments. Therefore, the use of manganese dioxide nanosheets with pH-regulated dual-enzyme mimic activities for dual-signal readout provides a new way for mucin 1 detection.


Manganese Compounds , Mucin-1 , Nanostructures , Oxides , Manganese Compounds/chemistry , Hydrogen-Ion Concentration , Mucin-1/analysis , Oxides/chemistry , Nanostructures/chemistry , Humans , Colorimetry/methods , Benzidines/chemistry , Pressure , Biosensing Techniques/methods , Hydrogen Peroxide/analysis , Hydrogen Peroxide/chemistry , Aptamers, Nucleotide/chemistry
20.
Ger Med Sci ; 22: Doc02, 2024.
Article En | MEDLINE | ID: mdl-38651020

Background: During articulation the velopharynx needs to be opened and closed rapidly and a tight closure is needed. Based on the hypothesis that patients with cleft lip and palate (CLP) produce lower pressures in the velopharynx than healthy individuals, this study compared pressure profiles of the velopharyngeal closure during articulation of different sounds between healthy participants and patients with surgically closed unilateral CLP (UCLP) using high resolution manometry (HRM). Materials and methods: Ten healthy adult volunteers (group 1: 20-25.5 years) and ten patients with a non-syndromic surgically reconstructed UCLP (group 2: 19.1-26.9 years) were included in this study. Pressure profiles during the articulation of four sounds (/i:/, /s/, /ʃ/ and /n/) were measured by HRM. Maximum, minimum and average pressures, time intervals as well as detection of a previously described 3-phase-model were compared. Results: Both groups presented with similar pressure curves for each phoneme with regards to the phases described and pressure peaks, but differed in total pressures. An exception was noted for the sound /i:/, where a 3-phase-model could not be seen for most patients with UCLP. Differences in velopharynx pressures of 50% and more were found between the two groups. Maximum and average pressures in the production of the alveolar fricative reached statistical significance. Conclusions: It can be concluded that velopharyngeal pressures of patients with UCLP are not sufficient to eliminate nasal resonance or turbulence during articulation, especially for more complex sounds. These results support a general understanding of hypernasality during speech implying a (relative) velopharyngeal insufficiency.


Cleft Lip , Cleft Palate , Pressure , Humans , Cleft Palate/physiopathology , Cleft Palate/complications , Cleft Palate/surgery , Cleft Lip/physiopathology , Cleft Lip/complications , Cleft Lip/surgery , Male , Adult , Female , Young Adult , Manometry/methods , Phonetics , Velopharyngeal Insufficiency/physiopathology , Velopharyngeal Insufficiency/etiology , Pharynx/physiopathology , Case-Control Studies
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