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1.
OTO Open ; 8(3): e160, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38974179

RESUMEN

Objective: Tragal pumping (TP) is a practice of pushing on the tragus to raise pressure within the external auditory canal and is a commonly recommended adjunctive maneuver believed to facilitate the introduction of ototopical medications into the middle ear cavity via a tympanostomy tube. To investigate the efficacy of TP in the penetration of eardrops into the middle ear cavity via tympanostomy tube, we established the novel tympanostomy tube-rat model. We investigated the histology of the middle ear to determine the efficacy in moving fluid into the middle ear. Study Design: Prospective controlled animal study. Setting: Animal laboratory in a university hospital. Methods: Ten rats were recruited, and a tympanostomy tube insertion and green dye eardrops into outer ears were performed on bilateral ears. TP was performed only on 1 ear and was not applied on the other ear in each rat. Green dye in a middle ear cavity in hematoxylin and eosin-stained temporal bone sections was evaluated by blinded experts in microscopic anatomy (staining grade) and by using Image J software (staining level). The results of these 2 methods were statistically validated. Results: The staining grade (P < .001) and the staining level (P < .001) were significantly higher in the ears which we applied TP than in the control ears. The results of 2 methods were significantly and positively correlated (r = .898, P < .001). Conclusion: Our results showed that the TP accelerate the penetration of eardrops into the middle ear cavity in the tympanostomy tube-rat model.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38980487

RESUMEN

Research on the migration behaviors of contaminants in the aquitard has been deficient for an extended period. Clay is commonly employed as an impermeable layer or barrier to stop the migration of contaminants. However, under certain conditions, the clay layer may exhibit permeability to water, thereby allowing contaminants to infiltrate and potentially contaminate adjacent aquifers. Consequently, it holds immense importance to scrutinize and investigate the migration characteristics of light non-aqueous phase liquid (LNAPL) within the aquitard for the purposes of groundwater pollution control and remediation. To evaluate the environmental risk posed by organic contaminants in the aquitard, an experimental model was formulated and devised to monitor the LNAPL concentration in the aquitard under pumping conditions. The correlation between pumping rate and LNAPL concentration was investigated. A self-developed plexiglass sandbox model was used to simulate the migration characteristics of LNAPL in the aquitard under pumping conditions. Four experimental scenarios were designed, varying pumping rates, aquitard thicknesses, and groundwater level changes. The LNAPL concentration curve was derived by systematically tracking and analyzing LNAPL levels at various locations within the aquitard. The results indicated that higher pumping rates corresponded to increased migration of LNAPL, resulting in greater LNAPL ingress into the pumping well during extraction. A thicker aquitard demonstrated a more pronounced inhibitory effect on LNAPL, leading to an extended penetration time of LNAPL within the aquitard. The drawdown within the aquitard exerted a discernible influence on LNAPL migration, with the LNAPL concentration continuing to decrease in tandem with declining water levels during pumping. These research findings can establish a scientific foundation for the control and remediation of contaminants within aquitards.

3.
Adv Healthc Mater ; : e2400993, 2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38850126

RESUMEN

Ideal hemostatic materials for the emergency rescue of war and traffic accident sufferers are essential to significantly control hemorrhage, reduce patient discomfort, and improve the survival ratio. However, most hemostats absorb blood quickly in contact with the wound; and then, adhere to blood clots, resulting in breaking scabs and tearing the wound when the materials are removed. Herein, an effective Janus amphipathic hemostatic dressing (Fiber@Gel/Ca2+/KL) with a fiber layer (polylactic acid/carboxymethyl chitosan) and a hydrogel layer (polyvinyl alcohol, carboxymethyl chitosan, Ca2+, and kaolin) is reported. Such a composite dressing unidirectionally drains the excessive serum from its hydrophobic side (fiber layer) to its hydrophilic side (hydrogel layer), so-called self-pumping, thereby further concentrating coagulated factors (including red blood cells and platelets). Further, Ca2+ diffused from the hydrogel layer subsequently activates platelets and coagulation cascade. Besides, the Fiber@Gel/Ca2+/KL exhibits specific blood-clot anti-adhesion property on the fiber layer, making the dressing easily and safely peel off from the wound. It is believed that this novel hemostatic dressing with good hemostatic performance, easy clots removal, and excellent biocompatibility is expected to be used as a safe and efficient hemostatic dressing in clinical applications.

4.
Midwifery ; 136: 104039, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38909553

RESUMEN

PROBLEM: Breast pumping practices have scope for improvement. BACKGROUND: Breast milk weight measurement can be used to evaluate milk flow pattern dynamics during breast pumping. AIM: To determine inter-individual differences in milk flow patterns and their practical implications based on high milk flow rate period (HFP) data among Japanese women expressing breast milk using an electric pump. METHODS: This cross-sectional, observational study analysed data from 19 women (33.0 ± 3.9 years) nursing 1-6-month-old infants and with previous breast milk expression experience. Breast milk was weighed continuously during a 15-min single-breast electric pumping session. The HFP features and flow rate time (≥0.1 g/s) were analysed to determine each individual's milk flow pattern. FINDINGS: The total expressed breast milk was 69.8 ± 42.5 g with a maximum individual flow rate of 0.5 ± 0.2 g/s. The breast milk yielded during the HFPs was 43.1 (34.4-81.3) g, accounting for 82.5 % (69.9-89.5 %) of the total expressed breast milk. HFP occurred 0-3 times during the 15-min session. Multiple discrete and continuous milk flow patterns were observed. Among those with discrete HFP, the HFP interval was 221 (68-371) s. Breast milk fat content changes and subjective residual milk measurements implied sufficient milk removal. A strong positive correlation was noted between HFP length and total breast milk expression volume. DISCUSSION: Individual differences in milk flow patterns were observed among the women using HFP. Milk flow patterns were consistent with previous reports. CONCLUSION: Milk flow pattern data can be used to guide individualised lactation support.

5.
Micromachines (Basel) ; 15(6)2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38930687

RESUMEN

A molecular pump is the core component of vacuum systems in portable mass spectrometers and other analytical instruments. The forms of the existing molecular pumps mainly are the combinations of vertical bleed and compression channel, which have the shortcomings of heavy mass and large volume, which seriously restricts the application and development of portable mass spectrometers. Aiming at the problems of low strength and insufficient pumping performance under the miniaturization constraints (mass of 1.8 kg; exhaust diameter of 25 mm) of molecular pumps, a compound pump consisting of a horizontal bleed channel and multi-stage spiral compression channel is proposed. The pumping principle of the compound molecular pump is analyzed to obtain its preliminary structural size parameters. The test particle Monte Carlo method is presented for establishing an aerodynamic model for a high-speed small compound molecular pump, which can be used to investigate the pumping performance of bleed blades and compression channels in a thin air environment. On the basis of the aerodynamic model, the NNIA multi-objective optimization algorithm is presented to optimize the structural parameters of the compound molecular pump. After structural parameter optimization, the maximum flow rate and compression ratio of the compound molecular pump are increased by 13.6% and 41.6%, respectively. The experimental results of the pumping performance show that the predicted data of the aerodynamic model are in good agreement with the experimental data, with an error of 12-27%. Namely, the established aerodynamic model has high accuracy and the optimized structural parameters of the compound molecular pump can provide basic conditions for the large-scale application and promotion of portable mass spectrometers.

6.
Anticancer Res ; 44(7): 3185-3191, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38925808

RESUMEN

BACKGROUND/AIM: The porous glass membrane pumping emulsification device enhances local therapeutic effects of transarterial chemoembolization for hepatocellular carcinoma (HCC); however, limited clinical outcomes have been reported. This study aimed to investigate the efficacy and safety of transarterial chemoembolization using the glass membrane pumping emulsification device for HCC. PATIENTS AND METHODS: Between 2019 and 2023, 58 patients (median age=73 years) with unresectable HCC underwent 73 transarterial chemoembolizations using the glass membrane pumping emulsification device at the Nagoya University Hospital. Treatment effects were assessed using contrast-enhanced computed tomography 1-3 months after therapy and every 2-3 months thereafter. RESULTS: The median size of treated tumors was 25.5 mm (45 solitary nodules). The median dosage of ethiodized oil mixed with the epirubicin solution was 3 ml. Complete and partial response were observed in 73% and 11% of patients, respectively. Local control rates at 6 and 12 months were 82.8% and 59.8%, respectively. The median time to recurrence after treatment was 581 days. No major treatment-related complications occurred. The number of tumors and therapeutic effects of the initial transarterial chemoembolization were significantly associated with better local control. CONCLUSION: The glass membrane pumping emulsification device facilitated the accumulation of more concentrated ethiodized oil within the tumor and effective local control.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Vidrio , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/patología , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patología , Quimioembolización Terapéutica/métodos , Quimioembolización Terapéutica/instrumentación , Masculino , Femenino , Anciano , Persona de Mediana Edad , Resultado del Tratamiento , Anciano de 80 o más Años , Porosidad , Epirrubicina/administración & dosificación , Emulsiones , Aceite Etiodizado/administración & dosificación , Adulto
7.
Ecology ; : e4376, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38934351
8.
J Math Biol ; 89(1): 13, 2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38879850

RESUMEN

In this paper, we introduce the numerical strategy for mixed uncertainty propagation based on probability and Dempster-Shafer theories, and apply it to the computational model of peristalsis in a heart-pumping system. Specifically, the stochastic uncertainty in the system is represented with random variables while epistemic uncertainty is represented using non-probabilistic uncertain variables with belief functions. The mixed uncertainty is propagated through the system, resulting in the uncertainty in the chosen quantities of interest (QoI, such as flow volume, cost of transport and work). With the introduced numerical method, the uncertainty in the statistics of QoIs will be represented using belief functions. With three representative probability distributions consistent with the belief structure, global sensitivity analysis has also been implemented to identify important uncertain factors and the results have been compared between different peristalsis models. To reduce the computational cost, physics constrained generalized polynomial chaos method is adopted to construct cheaper surrogates as approximations for the full simulation.


Asunto(s)
Simulación por Computador , Modelos Cardiovasculares , Peristaltismo , Procesos Estocásticos , Peristaltismo/fisiología , Incertidumbre , Humanos , Conceptos Matemáticos , Animales , Corazón/fisiología , Modelos Biológicos , Dinámicas no Lineales
9.
Angew Chem Int Ed Engl ; : e202406551, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38822492

RESUMEN

It has recently been shown that a bolus of hyperpolarized nuclear spins can yield stimulated emission signals similar in nature to maser signals, potentially enabling new ways of sensing hyperpolarized contrast media, including most notably [1-13C]pyruvate that is under evaluation in over 50 clinical trials for metabolic imaging of cancer. The stimulated NMR signal emissions lasting for minutes do not require radio-frequency excitation, offering unprecedented advantages compared to conventional MR sensing. However, creating nuclear spin maser emission is challenging in practice due to stringent fundamental requirements, making practical in vivo applications hardly possible using conventional passive MR detectors. Here, we demonstrate the utility of a wireless NMR maser detector, the quality factor of which was enhanced 22-fold (to 1,670) via parametric pumping. This active-feedback technique breaks the intrinsic fundamental limit of NMR detector circuit quality factor. We show the use of parametric pumping to reduce the threshold requirement for inducing nuclear spin masing at 300 MHz resonance frequency in a preclinical MRI scanner. Indeed, stimulated emission from hyperpolarized protons was obtained under highly unfavorable conditions of low magnetic field homogeneity (T2* of 3 ms). Greater gains of the quality factor of the MR detector (up to 1 million) were also demonstrated.

10.
PNAS Nexus ; 3(6): pgae195, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38827815

RESUMEN

The lymphatic system plays a vital role in maintaining fluid balance in living tissue and serves as a pathway for the transport of antigen, immune cells, and metastatic cancer cells. In this study, we investigate how the movement of cells through a contracting lymphatic vessel differs from steady flow, using a lattice Boltzmann-based computational model. Our model consists of cells carried by flow in a 2D vessel with regularly spaced, bi-leaflet valves that ensure net downstream flow as the vessel walls contract autonomously in response to calcium and nitric oxide levels regulated by stretch and shear stress levels. The orientation of the vessel with respect to gravity, which may oppose or assist fluid flow, significantly modulates cellular motion due to its effect on the contraction dynamics of the vessel, even when the cells themselves are neutrally buoyant. Additionally, our model shows that cells are carried along with the flow, but when the vessel is actively contracting, they move faster than the average fluid velocity. We also find that the fluid forces cause significant deformation of the compliant cells, especially in the vicinity of the valves. Our study highlights the importance of considering the complex, transient flows near the valves in understanding cellular motion in lymphatic vessels.

11.
Biofouling ; 40(3-4): 290-304, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38785127

RESUMEN

Thermal bubble-driven micro-pumps are an upcoming micro-actuator technology that can be directly integrated into micro/mesofluidic channels, have no moving parts, and leverage existing mass production fabrication approaches. These micro-pumps consist of a high-power micro-resistor that boils fluid in microseconds to create a high-pressure vapor bubble which performs mechanical work. As such, these micro-pumps hold great promise for micro/mesofluidic systems such as lab-on-a-chip technologies. However, to date, no current work has studied the interaction of these micro-pumps with biofluids such as blood and protein-rich fluids. In this study, the effects of organic fouling due to egg albumin and bovine whole blood are characterized using stroboscopic high-speed imaging and a custom deep learning neural network based on transfer learning of RESNET-18. It was found that the growth of a fouling film inhibited vapor bubble formation. A new metric to quantify the extent of fouling was proposed using the decrease in vapor bubble area as a function of the number of micro-pump firing events. Fouling due to egg albumin and bovine whole blood was found to significantly degrade pump performance as well as the lifetime of thermal bubble-driven micro-pumps to less than 104 firings, which may necessitate the use of protective thin film coatings to prevent the buildup of a fouling layer.


Asunto(s)
Incrustaciones Biológicas , Incrustaciones Biológicas/prevención & control , Animales , Bovinos , Albúminas , Dispositivos Laboratorio en un Chip , Albúmina Sérica Bovina/química
12.
Nano Lett ; 24(22): 6538-6544, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38771703

RESUMEN

With a seminal work of Raghu and Haldane in 2008, concepts of topology have been introduced into optical systems, where some of the most promising routes to an application are efficient and highly coherent topological lasers. While some attempts have been made to excite such structures electrically, the majority of published experiments use a form of laser excitation. In this paper, we use a lattice of vertical resonator polariton micropillars to form an exponentially localized topological Su-Schrieffer-Heeger defect. Upon electrical excitation, the system unequivocally shows polariton lasing from the topological defect using a carefully placed gold contact. Despite the presence of doping and electrical contacts, the polariton band structure clearly preserves its topological properties. At high excitation power the Mott density is exceeded, leading to highly efficient lasing in the weak coupling regime. This work is an important step toward applied topological lasers using vertical resonator microcavity structures.

13.
BMC Pregnancy Childbirth ; 24(1): 367, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38750490

RESUMEN

BACKGROUND: In the U.S., employees often return to work within 8-12 weeks of giving birth, therefore, it is critical that workplaces provide support for employees combining breastfeeding and work. The Affordable Care Act requires any organization with more than 50 employees to provide a space other than a restroom to express breastmilk and a reasonable amount of time during the workday to do so. States and worksites differ in the implementation of ACA requirements and may or may not provide additional support for employees combining breastfeeding and work. The purpose of this study was to conduct an analysis of the policies and resources available at 26 institutions within a state university system to support breastfeeding when employees return to work after giving birth. METHODS: Survey data was collected from Well-being Liaisons in the human resources departments at each institution. In addition, we conducted a document review of policies and online materials at each institution. We used univariate statistics to summarize survey results and an inductive and deductive thematic analysis to analyze institutional resources available on websites and in policies provided by the liaisons. RESULTS: A total of 18 (65.3%) liaisons participated in the study and revealed an overall lack of familiarity with the policies in place and inconsistencies in the resources offered to breastfeeding employees across the university system. Only half of the participating liaisons reported a formal breastfeeding policy was in place on their campus. From the document review, six major themes were identified: placing the burden on employees, describing pregnancy or postpartum as a "disability," having a university-specific policy, inclusion of break times for breastfeeding, supervisor responsibility, and information on lactation policies. CONCLUSION: The review of each institution's online resources confirmed the survey findings and highlighted the burden placed on employees to discover the available resources and advocate for their needs. This paper provides insight into how institutions support breastfeeding employees and provides implications on strategies to develop policies at universities to improve breastfeeding access for working parents.


Asunto(s)
Lactancia Materna , Política Organizacional , Reinserción al Trabajo , Lugar de Trabajo , Humanos , Lactancia Materna/estadística & datos numéricos , Femenino , Universidades , Encuestas y Cuestionarios , Estados Unidos , Lactancia , Patient Protection and Affordable Care Act , Adulto
14.
Int J Biol Macromol ; 267(Pt 2): 131563, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38626837

RESUMEN

Excessive exudation from the wound site and the difficulty of determining the state of wound healing can make medical management more difficult and, in extreme cases, lead to wound deterioration. In this study, we fabricated a pH-sensitive colorimetric chronic wound dressing with self-pumping function using electrostatic spinning technology. It consisted of three layers: a polylactic acid-curcumin (PCPLLA) hydrophobic layer, a hydrolyzed polyacrylonitrile (HPAN) transfer layer, and a polyacrylonitrile-purple kale anthocyanin (PAN-PCA) hydrophilic layer. The results showed that the preparation of porous PLLA fiber membrane loaded with 0.2 % Cur was achieved by adjusting the spinning-related parameters, which could ensure that the composite dressing had sufficient anti-inflammatory, antibacterial and antioxidant properties. The HPAN membrane treated with alkali for 30 min had significantly enhanced liquid wetting ability, and the unidirectional transport of liquid could be achieved by simple combination with the 20 um PCPLLA fiber membrane. In addition, the 4 % loaded PCA showed more obvious color difference than the colorimetric membrane. In vivo and ex vivo experiments have demonstrated the potential of multifunctional dressings for the treatment of chronic wounds.


Asunto(s)
Vendajes , Curcumina , Poliésteres , Cicatrización de Heridas , Concentración de Iones de Hidrógeno , Poliésteres/química , Porosidad , Animales , Cicatrización de Heridas/efectos de los fármacos , Curcumina/química , Curcumina/farmacología , Resinas Acrílicas/química , Antocianinas/química , Antocianinas/farmacología , Interacciones Hidrofóbicas e Hidrofílicas , Ratas , Antibacterianos/farmacología , Antibacterianos/química , Masculino , Antioxidantes/farmacología , Antioxidantes/química , Brassica/química
15.
Adv Sci (Weinh) ; 11(25): e2400967, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38626379

RESUMEN

Recently, the altermagnetic materials with spin splitting effect (SSE), have drawn significant attention due to their potential to the flexible control of the spin polarization by the Néel vector. Here, the direct and inverse altermagnetic SSE (ASSE) in the (101)-oriented RuO2 film with the tilted Néel vector are reported. First, the spin torque along the x-, y-, and z-axis is detected from the spin torque-induced ferromagnetic resonance (ST-FMR), and the z-spin torque emerges when the electric current is along the [010] direction, showing the anisotropic spin splitting of RuO2. Further, the current-induced modulation of damping is used to quantify the damping-like torque efficiency (ξDL) in RuO2/Py, and an anisotropic ξDL is obtained and maximized for the current along the [010] direction, which increases with the reduction of the temperature, indicating the present of ASSE. Next, by way of spin pumping measurement, the inverse altermagnetic spin splitting effect (IASSE) is studied, which also shows a crystal direction-dependent anisotropic behavior and temperature-dependent behavior. This work gives a comprehensive study of the direct and inverse ASSE effects in the altermagnetic RuO2, inspiring future altermagnetic materials and devices with flexible control of spin polarization.

16.
ACS Synth Biol ; 13(4): 1355-1364, 2024 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-38569139

RESUMEN

Adenosine triphosphate (ATP)-producing modules energized by light-driven proton pumps are powerful tools for the bottom-up assembly of artificial cell-like systems. However, the maximum efficiency of such modules is prohibited by the random orientation of the proton pumps during the reconstitution process into lipid-surrounded nanocontainers. Here, we overcome this limitation using a versatile approach to uniformly orient the light-driven proton pump proteorhodopsin (pR) in liposomes. pR is post-translationally either covalently or noncovalently coupled to a membrane-impermeable protein domain guiding orientation during insertion into preformed liposomes. In the second scenario, we developed a novel bifunctional linker, trisNTA-SpyTag, that allows for the reversible connection of any SpyCatcher-containing protein and a HisTag-carrying protein. The desired protein orientations are verified by monitoring vectorial proton pumping and membrane potential generation. In conjunction with ATP synthase, highly efficient ATP production is energized by the inwardly pumping population. In comparison to other light-driven ATP-producing modules, the uniform orientation allows for maximal rates at economical protein concentrations. The presented technology is highly customizable and not limited to light-driven proton pumps but applicable to many membrane proteins and offers a general approach to overcome orientation mismatch during membrane reconstitution, requiring little to no genetic modification of the protein of interest.


Asunto(s)
Adenosina Trifosfato , Liposomas , Liposomas/metabolismo , Adenosina Trifosfato/metabolismo , Luz , Bombas de Protones/metabolismo , Proteínas de la Membrana/metabolismo
17.
Data Brief ; 54: 110375, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38623543

RESUMEN

The Response Surface Methodology (RSM) was employed to examine the impact of the pumping system in a photovoltaic solar water pumping system, while operating under ideal conditions. The input parameters for optimizing the pump performance of the PV water pump include three parameters: Solar irradiance (550-950, W/m2), temperature (30-45, °C), and voltage (420-540, V). The experimental values of PV water pump efficiency showed that the efficiency of PV water pumps was in the range of 55.24-80.80% of the experiment. At a solar irradiance of 750 W/m2, a voltage of 480 V and a temperature of 37.5 °C shows the maximum efficiency of the solar PV water pump systems was 80.80% under optimal conditions. This work demonstrates the potential of solar water pumps as a reliable, cost-effective, and environmentally friendly solution to support agriculture in remote areas. In addition, the costs and economic parameters of solar photovoltaic water pumps and conventional systems were compared by the social return on investment (SROI) evaluation. This indicates that sales are profitable or create social value that benefits society and local stakeholders in remote areas. This work demonstrates the potential of solar water pumps as a reliable, cost-effective, and environmentally friendly solution to support agriculture in remote areas.

18.
Materials (Basel) ; 17(8)2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38673115

RESUMEN

Buried depressed-cladding waveguides were fabricated in 0.7-at.% Nd:Ca3Li0.275Nb1.775Ga2.95O12 (Nd:CLNGG) and 7.28-at.% Yb:CLNGG disordered laser crystals grown by Czochralski method. Circular waveguides with 100 µm diameters were inscribed in both crystals with picosecond (ps) laser pulses at 532 nm of 0.15 µJ energy at 500 kHz repetition rate. A line-by-line writing technique at 1 mm/s scanning speed was used. Laser emission at 1.06 µm (with 0.35 mJ pulse energy) and at 1.03 µm (with 0.16 mJ pulse energy) was obtained from the waveguide inscribed in Nd:CLNGG and Yb:CLNGG, respectively, employing quasi-continuous wave pumping with fiber-coupled diode lasers. The waveguide realized in RE3+-doped CLNGG crystals using ps-laser pulses at high repetition rates could provide Q-switched or mode-locked miniaturized lasers for a large number of photonic applications.

19.
Heliyon ; 10(7): e29339, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38633634

RESUMEN

This study applies Jellyfish Search Algorithm and five other algorithms to minimize the electricity generation cost of two hybrid systems for one operating day. The first system comprises one pumped storage hydroelectric plant and two thermal power plants. The second system is expanded by integrating one wind and one solar photovoltaic power plant into the first system. For each system during one operating day, the pumped storage hydroelectric plant with only generation mode acts as a conventional hydroelectric plant in the first scenario. Still, it can run pumps to store water and produce electricity in the second scenario. As a result, JSA can reach smaller costs than all compared algorithms, from about 1 % to higher than 10 % for two scenarios in the two systems. The comparisons of generation cost indicate the second scenario with the pumped storage hydroelectric plant can reach a smaller cost than the first scenario with the conventional hydroelectric power plant by $53,359.7, corresponding to 7.4 % in the first system and $39,472.8, corresponding to 6.95 % in the second system. Therefore, the water storage function of the pumped storage hydroelectric plant is very effective in reducing the electricity generation costs for hybrid power systems.

20.
Environ Pollut ; 350: 124020, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38657891

RESUMEN

Groundwater exploitation in a riparian zone causes water infiltration from the river into the aquifer. Owing to adsorption and redox reactions along the flow path, the quality of water flowing from the river to groundwater wells is variably altered. The riverbed composition often involves spatiotemporal differences due to frequent changes in hydrological conditions. These changes create uncertainties in the transport and removal of solutes in the river water. In this study, the hydrodynamic field associated with riparian groundwater, changes in the structure of riverbed sediments caused by erosion and deposition, fluctuations in surface water and groundwater levels, and the removal efficiency of pollutants from groundwater through pumping were investigated. This involved in situ monitoring and sample testing of the composition of the river water, riverbed sediments, riverbed pore water, and groundwater during dry and wet seasons. Implementation of field in situ column experiments and molecular biology evidences were conducive to identifying the main biogeochemical processes occurring in the riverbed. The findings indicated that riparian groundwater exploitation alters the natural groundwater flow field, while fine sand deposition and microbial adsorption can reduce river recharge to aquifers by diminishing riverbed hydraulic conductivity. Shallow sediments within 1 m depth mainly involve NO3- reduction and E. coli adsorption. Reductive dissolution of Mn dominates in the deeper sediments. Additionally, reductive dissolution of Fe and dissimilatory nitrate reduction to ammonium (DNRA) drive high Fe2+ and NH4+ concentrations in groundwater. The findings can improve the management of riparian groundwater and aid in the optimization of a plan for its exploitation.


Asunto(s)
Monitoreo del Ambiente , Filtración , Agua Subterránea , Ríos , Contaminantes Químicos del Agua , Agua Subterránea/química , Contaminantes Químicos del Agua/análisis , Ríos/química , Monitoreo del Ambiente/métodos , Hidrología , Sedimentos Geológicos/química
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