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1.
Sci Rep ; 14(1): 15765, 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38982222

ABSTRACT

Within the scope of sustainable development, integrating electric vehicles (EVs) and renewable energy sources (RESs) into power grids offers a number of benefits. These include reducing greenhouse gas emissions, diversifying energy sources, and promoting the use of green energy. Although the literature on hosting capacity (HC) models has grown, there is still a noticeable gap in the discussion of models that successfully handle transmission expansion planning (TEP), demand response (DR), and HC objectives simultaneously. Combining TEP, DR, and HC objectives in one model optimizes resource use, enhances grid stability, supports renewable and EV integration, and aligns with regulatory and market demands, resulting in a more efficient, reliable, and sustainable power system. This research presents an innovative two-layer HC model, including considerations for TEP and DR. The model determines the highest degree of load shifting appropriate for incorporation into power networks in the first layer. Meanwhile, the second layer focuses on augmenting the RES and EVs' hosting capability and modernizing the network infrastructure. System operators can choose the best scenario to increase the penetration level of EVs and RESs with the aid of the proposed model. The proposed model, which is formulated as a multi-objective mixed-integer nonlinear optimization problem, uses a hierarchical optimization technique to identify effective solutions by combining the particle swarm optimization algorithm and the crayfish optimizer. When compared to traditional methods, the results obtained from implementing the proposed hierarchical optimization algorithm on the Garver network and the IEEE 24-bus system indicated how effective it is at solving the presented HC model. The case studies demonstrated that integrating DR into the HC problem reduced peak load by 10.4-23.25%. The findings also highlighted that DR did not impact the total energy consumed by EVs throughout the day, but it did reshape the timing of EV charging, creating more opportunities for integration during periods of high demand. Implementing DR reduced the number of projects needed and, in some cases, led to cost savings of up to 12.3%.

2.
Heliyon ; 10(12): e33115, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38984303

ABSTRACT

The ride-sharing trend is booming because of modern technologies and plays a significant role in transitioning to sustainable transportation methods. This study utilizes a comprehensive dataset collected from an online survey administered to over 1300 individuals in Bangladesh in 2023. Its specific focus is to examine the usage patterns of ride-sharing applications, such as Pathao and Uber. It builds upon previous research to analyze the factors influencing the use of these services and current trends in shared transportation. Additionally, it investigates the challenges associated with utilizing shared transportation amenities and proposes potential improvements to make ride-sharing or pooling more attractive. The study diligently worked to establish an inclusive framework and terminology to enhance policies and gain a more detailed understanding of the transportation choices and requirements of communities. To bridge the gap between theory and practice, we adopted an implementation-oriented research approach and conducted a comprehensive quantitative and inferential analysis of the survey data. The inclination of an individual to opt for or perceive collective or merged services depends on several demographic, geographical, and built-environment factors. The findings highlight the necessity of enhanced security measures, increased public awareness of ride-sharing benefits, and the formulation of legislative measures to promote sustainable mobility. Two examples of potential measures we have found to improve and encourage the use of ride-sharing services include reducing uncertainty about shared rides and minimizing passenger discomfort. These measures can be implemented through operational adjustments, government regulations, and employer programs. An essential conclusion was reached regarding the importance of prioritizing improvements in ride-sharing operations, rather than relying solely on cash incentives to promote behavioral change. Furthermore, it was determined that regardless of the changes, policies, or programs implemented, it is imperative to enhance public awareness and education.

3.
Investig Clin Urol ; 65(4): 326-333, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38978212

ABSTRACT

PURPOSE: This study aimed to provide the basic data needed to estimate future urologist supply and demand by applying various statistical models related to healthcare utilization. MATERIALS AND METHODS: Data from multiple sources, including the Yearbook of Health and Welfare Statistics, Korean Hospital Association, Korean Medical Association, and the Korean Urological Association, were used for supply estimation. Demand estimation incorporated data on both clinical and non-clinical urologists, along with future population estimates. In-and-out moves and demographic methods were employed for supply estimation, while the Bureau of Health Professions model was utilized for demand estimation. Supply estimation assumptions included fixed resident quotas, age-specific death rates, migration rates, and retirement age considerations. Demand estimation assumptions included combining clinical and nonclinical urologist demands, adjusting population size for age-related healthcare usage variations. Urologist productivity was determined by adjusting productivity levels to 100%, 90%, and 80% of the base year based on actual clinical practice volumes. RESULTS: Estimations of both demand and supply consistently indicate an oversupply of urologists until 2025, followed by an expected shortage by 2035 owing to increased deaths and retirements attributed to the aging urologist population. This shortage becomes more pronounced when employing more reliable models, such as logit or ARIMA (autoregressive integrated moving average), underscoring the growing need for urologists in the future. CONCLUSIONS: All estimation models estimated an oversupply of urologists until 2025, transitioning to a deficit due to reduced supply thereafter. However, considering potential unaccounted factors, greater effort is needed for accurate predictions and corresponding measures.


Subject(s)
Health Services Needs and Demand , Urologists , Urology , Republic of Korea , Humans , Urologists/supply & distribution , Urologists/statistics & numerical data , Health Services Needs and Demand/trends , Health Services Needs and Demand/statistics & numerical data , Urology/trends , Urology/statistics & numerical data , Forecasting , Middle Aged , Male , Workforce/statistics & numerical data , Workforce/trends , Female
4.
J Health Popul Nutr ; 43(1): 102, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38970138

ABSTRACT

Balancing is an essential challenge in healthcare systems that requires effective strategies. This study aims to address this crucial issue by suggesting a practical approach. We show the potential of balancing a regional healthcare system to improve its utility. We consider a regional healthcare system comprising multiple hospitals with different sizes, capacities, quality of service, and accessibility. We define a utility function for the system based on the sectorization concept, which endeavors to form a balance between hospitals in terms of essential outputs such as waiting times and demands. The dynamic nature of the system means that this balance degrades over time, necessitating periodic sectorization, which is called resectorization. Our methodology stands out for incorporating resectorization as a dynamic strategy, enabling more flexible and responsive adaptations to continuously changing healthcare needs. Unlike previous studies, based on a system-oriented approach, our resectorization scenarios include the periodic closure of some hospitals. This enables us to enhance both the capacity and quality of healthcare facilities. Furthermore, in contrast to other studies, we investigate the states of diminishing demand throughout the resectorization process. To provide empirical insights, we conduct a simulation using data from a real-world case study. Our analysis spans multiple time periods, enabling us to dynamically quantify the utility of the healthcare system. The numerical findings demonstrate that substantial utility improvements are attainable through the defined scenarios. The study suggests a practical solution to the critical challenge of balancing issues in regional healthcare systems.


Subject(s)
Delivery of Health Care , Humans , Quality of Health Care , Health Services Accessibility , Hospitals , Health Services Needs and Demand
5.
Front Sociol ; 9: 1415852, 2024.
Article in English | MEDLINE | ID: mdl-38979114

ABSTRACT

This research examines food delivery couriers' preferred employment status and factors explaining their opinions. Previous studies have used qualitative research methods and are unable to explain couriers' general views on employment status. In this research, a survey of 1,539 Wolt couriers was carried out in Finland with logistic regression, cross-tabulation, and content analysis as analysis methods. The results show that 56% of the couriers wanted to work as self-employed and 25% as employed. The opinion was most strongly explained by valuing work-related freedom and flexibility, which were associated with the right to refuse delivery tasks offered and to choose the amount of work, working hours and delivery vehicle. The preference for self-employment was also increased by the duration of courier work, one's own choice to work as a courier, and age. Freedom and flexibility are dependent on the sufficient availability of delivery tasks, posing challenges when the demand is low.

6.
Ecotoxicol Environ Saf ; 281: 116669, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38954908

ABSTRACT

In most of advanced oxidation processes (AOPs) used to destroy harmful organic chemicals in water/wastewater hydroxyl radical (•OH) reactions oxidize (increasing the oxygen/carbon ratio in the molecules) and mineralize (transforming them to inorganic molecules, H2O, CO2, etc.) these contaminants. In this paper, we used the radiolysis of water to produce •OH and characterised the rate of oxidation and mineralization by the dose dependences of the Chemical Oxygen Demand (COD) and Total Organic Carbon (TOC) content values. Analysis of the dose dependences for 34 harmful organic compounds showed large differences in the oxidation and mineralization rates and these parameters are characteristic to the given group of chemicals. E.g., the rate of oxidation is relatively low for fluoroquinolone antibiotics; it is high for ß-blocker medicines. Mineralization rates are low for both fluoroquinolones and ß-blockers. The one-electron-oxidant •OH in most cases induces two - four-electron-oxidations. Most of the degradation takes place gradually, through several stable molecule intermediates. However, based on the results it is likely, that some part of the oxidation and mineralization takes place parallel. The organic radicals formed in •OH reactions react with several O2 molecules and release several inorganic fragments during the radical life cycle.

7.
Midwifery ; 136: 104098, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38986390

ABSTRACT

BACKGROUND: The postpartum period is critical and challenging for women, implying emotional, physical, social and spiritual changes. For a positive postpartum experience, it is important to receive consistent information and support from health professionals. However, this is not always the case, as care is more focused on the newborn, forgetting the needs of the puerperal woman. AIM: The review aimed to map the published scientific knowledge about women's needs in the postpartum period. METHODS: A Scoping Review was carried out, according to the method proposed by The Joanna Briggs Institute, in the MEDLINE Complete, MedicLatina and CINAHL Complete databases, and were selected articles since 2017 that answered the research question "What is the available evidence on women's needs in the postpartum period?". For the selection of articles, the eligibility criteria were defined. RESULTS: A total of 6,647 articles were identified. After the exclusion of duplicate articles and the application of the eligibility criteria, at the end of the process, 27 articles were included in the review. The extracted data were grouped into four categories, which summarize the needs of women in the postpartum period: support, sharing, care and preparation for the postpartum period. CONCLUSION: In the articles analysed, women reveal that they do not feel prepared for the postpartum period and identify several unmet needs, so health education and parenting skills training during pregnancy are essential to improve the postpartum experience and the transition to parenthood.

8.
Int J Eat Disord ; 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38946135

ABSTRACT

OBJECTIVE: An unprecedented rise in eating disorder presentations has been documented in several countries during the COVID-19 pandemic. We explored this phenomenon by analyzing nationwide psychiatric admissions over 5 years, controlling for demographic variables. METHODS: We retrospectively analyzed all hospitalizations in New Zealand with a primary psychiatric diagnosis from 2017 to 2021, using Poisson regression to calculate admission rates by diagnosis, before and during the pandemic. Using Fisher's exact test and Poisson modeling, national data were validated against a manually collected sample of eating disorder admissions. RESULTS: Eating disorder admissions rose significantly during the pandemic (RR 1.48, p < 0.0001), while other diagnoses remained unchanged or decreased slightly. Anorexia nervosa in 10 to 19-year-old females drove increases, with persistent elevations noted in the 10-14 age group. Pandemic-associated increases were more striking for Maori (RR 2.55), the indigenous Polynesian population, compared with non-Maori (RR 1.43). CONCLUSIONS: Eating disorder hospital presentations increased during the COVID-19 pandemic, while other psychiatric presentations to hospital remained relatively unchanged. Possible drivers include disrupted routines, barriers to healthcare access, altered social networks, and increased social media use. Clinical services require additional resources to manage the increased disease burden, especially in vulnerable pediatric and indigenous populations. Ongoing monitoring will be required to establish the time-course of pandemic-related clinical demand.

9.
Clin Kidney J ; 17(7): sfae162, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38974818

ABSTRACT

Background: To estimate the projections of supply and demand for dialysis nurses (DNs) over 5 years in four European countries (France, Italy, Spain and the UK). Methods: This study modelled the nursing labour workforce across each jurisdiction by estimating the current nursing labour force, number of nursing graduates and the attrition rate. Results: France currently has the greatest demand for DNs (51 325 patients on dialysis), followed by Italy, the UK and Spain with 40 661, 30 301 and 28 007 patients on dialysis, respectively. The number of in-centre haemodialysis (HD) patients is expected to increase in the four countries, while the number of patients on home HD (HHD) or on peritoneal dialysis (PD) is expected to increase in the UK. Currently Italy has the greatest proportion of DNs (2.6%), followed by France (2.1%), Spain (1.7%) and the UK (1.5%). Estimation of the dialysis nursing staff growth rate over 5 years showed that the UK has the greatest estimated growth rate (6%), followed by Italy (2%), France (2%) and Spain (1%). Conclusions: Dialysis demand will increase in the coming years, which may exacerbate the DN shortage. Additionally, competencies and training requirements of DNs should be precisely defined. Finally, implementing and facilitating PD and HHD strategies would be helpful for patients, healthcare professionals and healthcare systems and can even help ease the DN shortage.

10.
Med X ; 2(1): 9, 2024.
Article in English | MEDLINE | ID: mdl-38975024

ABSTRACT

Hydrogels with particulates, including proteins, drugs, nanoparticles, and cells, enable the development of new and innovative biomaterials. Precise control of the spatial distribution of these particulates is crucial to produce advanced biomaterials. Thus, there is a high demand for manufacturing methods for particle-laden hydrogels. In this context, 3D printing of hydrogels is emerging as a promising method to create numerous innovative biomaterials. Among the 3D printing methods, inkjet printing, so-called drop-on-demand (DOD) printing, stands out for its ability to construct biomaterials with superior spatial resolutions. However, its printing processes are still designed by trial and error due to a limited understanding of the ink behavior during the printing processes. This review discusses the current understanding of transport processes and hydrogel behaviors during inkjet printing for particulate-laden hydrogels. Specifically, we review the transport processes of water and particulates within hydrogel during ink formulation, jetting, and curing. Additionally, we examine current inkjet printing applications in fabricating engineered tissues, drug delivery devices, and advanced bioelectronics components. Finally, the challenges and opportunities for next-generation inkjet printing are also discussed.

11.
Sci Rep ; 14(1): 16034, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38992090

ABSTRACT

The original load control model of microgrid based on demand response lacks the factors of incentive demand response, the overall satisfaction of users is low, the degree of demand response is low, the Time Of Use (TOU) price of peak-valley filling capacity is weak, and the peak-valley difference of load curve is large. Regarding the limitations of the current microgrid demand response model, this study further optimizes the flexible load control strategy and proposes a two-objective optimization model based on price and incentive. Meanwhile, the model is solved using an improved chaotic particle group algorithm. Finally, the microgrid load data were selected for simulation analysis. The simulation results showed that the comprehensive demand response of flexible control model proposed increased the overall satisfaction of users by 9.51%, the overall operating cost of microgrid suppliers decreased by 12.975/ten thousand yuan, the peak valley difference decreased by 4.61%, and the user demand response increased by 27.24%. The model effectively improves the overall profit of the supply side of the microgrid, improves the user satisfaction, and maximizes the linkage benefits of the supply and demand of the micro grid. In addition, the model effectively reduces the phenomenon of distributed power supply in the microgrid, and realizes the supply and demand matching of the whole load in the microgrid.

12.
World Neurosurg ; 2024 Jun 29.
Article in English | MEDLINE | ID: mdl-38950648

ABSTRACT

BACKGROUND: Preoperative opioid use has been well-studied in elective spinal surgery and correlated with numerous postoperative complications including increases in immediate postoperative opioid demand (POD), continued opioid use postoperatively, prolonged length of stay (LOS), readmissions, and disability. There is a paucity of data available on the use of preoperative opioids in surgery for spine trauma, possibly because there are minimal options for opioid reduction prior to emergent spinal surgery. Nevertheless, patients with traumatic spinal injuries are at a high risk for adverse postoperative outcomes. This study investigated the effects of preoperative opioid use on POD and LOS in spine trauma patients. METHODS: 130 patients were grouped into two groups for primary comparison: Group 1 (Preoperative Opioid Use, N=16) and Group 2 (No Opioid Use, N=114). Two subgroups of Group 2 were used for secondary analysis against Group 1: Group 3 (No Substance Abuse, N=95) and Group 4 (Other Substance Abuse, N=19). Multivariable analysis was used to determine if there were significant differences in POD and LOS. RESULTS: Primary analysis demonstrated that preoperative opioid users required an estimated 97.5 mg/day more opioid medications compared to non-opioid users (p<0.001). Neither primary nor secondary analysis showed a difference in LOS in any of the comparisons. CONCLUSIONS: Preoperative opioid users had increased POD compared to non-opioid users and patients abusing other substances, but there was no difference in LOS. We theorize the lack of difference in LOS may be due to the enhanced perioperative recovery protocol used, which has been demonstrated to reduce LOS.

13.
Clin Oral Investig ; 28(7): 410, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38954100

ABSTRACT

OBJECTIVES: Studies exploring variations in peripheral muscle oxygenation and pressure pain thresholds (PPT) of masticatory muscles in individuals with Temporomandibular Disorders (TMDs) are limited. The purpose of this study was to compare variations in peripheral oxygenation of the masseter muscle; PPT of the masseter and temporal muscles and correlate peripheral muscle oxygenation and PPT of the masseter muscle in individuals with different types of TMDs. MATERIALS AND METHODS: Cross-sectional study involving 116 participants classified into three groups: muscle group (MG, n = 32), joint group (JG, n = 30) and muscle-joint group (MJG, n = 54). Individuals aged 26.97 ± 6.93, 68.97% female, 31,03% males were included. All participants were evaluated using the Diagnostic Criteria for Temporomandibular Disorders, Near-infrared spectroscopy (NIRS) for peripheral muscle oxygenation and pressure algometer for PPT. RESULTS: There was no difference in masseter muscle oxygenation among groups. In the masseter muscle, a weakly positive correlation was observed between PPT and variation in tissue saturation index in the MG (rho = 0.365) and JG (rho = 0.317). In addition, the MJG expressed lower PPT (p = 0.004) than JG, demonstrating that MJG had more pain in this muscle. CONCLUSIONS: MJG have lower PPT in the masseter muscle. Although the PPT is dependent on the type of TMDs, the correlation between PPT and oxygenation is weak. All TMDs groups evaluated (MG, JG, MJG) showed hemodynamic similarities of the masseter muscle. CLINICAL RELEVANCE: Understanding pain thresholds and the hemodynamic behavior of the masticatory muscles contributes to a more assertive physiotherapeutic assessment in TMDs, serving as a basis for careful and individualized interventions.


Subject(s)
Masseter Muscle , Pain Measurement , Pain Threshold , Spectroscopy, Near-Infrared , Temporomandibular Joint Disorders , Humans , Male , Temporomandibular Joint Disorders/physiopathology , Female , Cross-Sectional Studies , Adult , Pain Threshold/physiology , Masseter Muscle/physiopathology , Facial Pain/physiopathology , Oxygen/metabolism , Temporal Muscle/physiopathology
14.
Article in English | MEDLINE | ID: mdl-38954332

ABSTRACT

In the context of China's green development and "dual carbon" goal, urbanization, as a way to achieve Chinese modernization, has a particularly important effect on green and low-carbon economic development. Firstly, this paper empirically analyzed the influence of urbanization on per capita carbon emissions using Chinese city data and a panel fixed-effects model. Then, the impact mechanisms of urbanization on carbon emissions were examined from both the demand and supply sides. Finally, we analyzed the differences in the transmission mechanisms of urbanization affecting carbon emissions in the eastern, central, and western regions. The results show that (1) urbanization increases per capita carbon emissions. However, this effect shows inter-regional differences, with more significant promotion effects in the eastern and central regions; (2) on the demand side, the residents' consumption intensity can drive carbon emissions, while the rise of human capital agglomeration suppresses carbon emissions; on the supply side, industrial structure can drive carbon emissions, while the increase of green technological innovation suppresses carbon emissions; (3) the consumption effect and the industry effect play a major role in the eastern and central regions, while the intermediary effect is not obvious in the western region. This study can provide important insights for synergizing urbanization and achieving carbon reduction commitments.

15.
Article in English | MEDLINE | ID: mdl-38954346

ABSTRACT

In a hydrogen economy, the primary energy source for industry, transportation, and power production is hydrogen gas. Green hydrogen can be generated and utilized in an environmentally friendly and sustainable manner; it seeks to displace fossil fuels. Finding a clean alternative energy source is becoming more crucial due to the depletion of fossil fuels and the major environmental pollution issues they bring when utilized extensively. The paper's objective is to analyze the factors affecting the economy of green hydrogen production pathways for sustainable development to decarbonize the world and the associated challenges faced in terms of technological, social, infrastructure, and people's perceptions while adopting green hydrogen. To achieve this, the research looked at a variety of areas relevant to green hydrogen, such as production techniques, industry applications, benefits for society and the environment, and challenges that need to be overcome before the technology is widely used. The most recent methods of producing hydrogen from fossil fuels, such as steam methane, partial oxidation, autothermal, and plasma reforming, as well as renewable energy sources including biomass and thermochemical reactions and water splitting. Grey hydrogen is now the least expensive type of hydrogen, but, in the future, green hydrogen's levelized cost of hydrogen (LCOH) is expected to be less than $2 per kilogram of hydrogen.

16.
Environ Sci Technol ; 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38968232

ABSTRACT

The ongoing transition toward electric vehicles (EVs) is changing materials used for vehicle production, of which the consequences for the environmental performance of EVs are not well understood and managed. We demonstrate that electrification coupled with lightweighting of automobiles will lead to significant changes in the industry's demand not only for battery materials but also for other materials used throughout the entire vehicle. Given the automotive industry's substantial consumption of raw materials, changes in its material demands are expected to trigger volatilities in material prices, consequently impacting the material composition and attractiveness of EVs. In addition, the materials recovered during end-of-life recycling of EVs as the vehicle fleet turns over will impact recycled material supplies both positively and negatively, impacting material availabilities and the economic incentive to engage in recycling. These supply chain impacts will influence material usage and the associated environmental performance of not only the automotive sector but also other metal-heavy industries such as construction. In light of these challenges, we propose the need for new research to understand the dynamic materials impacts of the EV transition that encompasses its implications on EV adoption and fleet life cycle environmental performance. Effectively coordinating the coevolution of material supply chains is crucial for making the sustainable transition to EVs a reality.

17.
J Environ Manage ; 365: 121698, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38968890

ABSTRACT

In China, over 65% of human activities are concentrated in cities, resulting in a conflict between the supply and demand of ecosystem services (ESs). To alleviate this problem, many cities have adopted eco-friendly development modes, however, the effectiveness of these models in reducing ESs supply-demand conflicts has not been comprehensively reviewed, and the human and natural drivers behind these relationship shifts remain unclear. To bridge this gap, this study analyzed the shifts in the relationships between supply and demand of ESs across China from 2010 to 2020 at a city level, as well as identified the human and natural drivers behind them. Firstly, the InVEST models were integrated with socioeconomic data to evaluate the supply and demand distribution for three pivotal ESs: water yield (WY), habitat quality (HQ), and soil retention (SR). Then, a four-quadrant diagram approach was proposed to enhance the analysis of their spatiotemporal relationships. Furthermore, random forest models were employed to examine the drivers of the shifts in these relationships. The results showed that WY and SR services witnessed growth until 2015, and then receded, while HQ saw a modest decline from 2010 to 2020. Spatial synergies in the supply and demand of ESs were primarily observed in the southern cities, with a significant northward extension by 2020. From a temporal perspective, the percentage of cities achieving coordination in WY and SR services increased from 32.6% to 57.3%, respectively, in the 2010-2015 period to 42.4% and 63.3% between 2015 and 2020, meanwhile, HQ service conflicts diminished from 58.7% to 53.5%. The changes in socioeconomic and land use factors contributed to 64.3%, 36.1%, and 33.3% of the shifts in the supply-demand relationship for HQ, WY, and SR services, respectively. Our analysis highlights the potential of human-driven ecological management to enhance the balance of this relationship. It can support the design of city-specific policies that foster a balance between ecological processes and socio-economic development.

18.
J Environ Sci (China) ; 146: 127-139, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38969441

ABSTRACT

Water-level reduction frequently occurs in deep reservoirs, but its effect on dissolved oxygen concentration is not well understood. In this study we used a well-established water quality model to illustrate effects of water level dynamics on oxygen concentration in Rappbode Reservoir, Germany. We then systematically elucidated the potential of selective withdrawal to control hypoxia under changing water levels. Our results documented a gradual decrease of hypolimnetic oxygen concentration under decreasing water level, and hypoxia occurred when the initial level was lower than 410 m a.s.l (71 m relative to the reservoir bottom). We also suggested that changes of hypoxic region, under increasing hypolimnetic withdrawal discharge, followed a unimodal trajectory with the maximum hypoxic area projected under the discharge between 3 m3/sec and 4 m3/sec. Besides, our results illustrated the extent of hypoxia was most effectively inhibited if the withdrawal strategy was applied at the end of stratification with the outlet elevation at the deepest part of the reservoir. Moreover, hypoxia can be totally avoided under a hybrid elevation withdrawal strategy using surface withdrawal during early and mid stratification, and deep withdrawal at the end of stratification. We further confirmed the decisive role of thermal structure in the formation of hypoxia under water-level reduction and withdrawal strategies. We believe the conclusions from this study can be applied to many deep waters in the temperate zone, and the results should guide stakeholders to mitigate negative impacts of hypoxia on aquatic ecosystems.


Subject(s)
Drinking Water , Water Supply , Germany , Drinking Water/chemistry , Water Quality , Environmental Monitoring/methods , Oxygen/analysis
19.
J Voice ; 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38969542

ABSTRACT

BACKGROUND: The term vocal demand response refers to how speakers meet vocal demands. Vocal loading tasks with predetermined demand parameters (duration, pitch, loudness, etc) have been used in research to study the vocal demand response; these have historically consisted of loud sustained vowel and loud speech tasks. Tasks founded on laryngeal diadochokinesis (LDDK) may be viable alternatives, especially if demand parameters such as exercise-rest ratio and fluid back pressure are concurrently modulated. OBJECTIVES: To explore the effects of four fluid back pressure conditions (0, 5, 10, and 15 cm H2O) on several measures of subjective participant experience, feasibility, and tolerability during intervallic laryngeal diadochokinetic exercise. METHODS: Participants (n = 12) completed 15-minute trials of LDDK in 30-second rest and exercise intervals against four counterbalanced back pressure conditions: 0, 5, 10, and 15 cm H2O. The effects of back pressure on (1) ratings of perceived vocal exertion, (2) prevalence of adverse effects such as shortness of breath or lightheadedness, (3) subjective difficulty of sustaining LDDK, (4) number of exercise intervals completed, (5) rankings of participant-preferred back pressure levels, and (6) expert ratings of auditory-perceptual diadochokinetic strength were assessed descriptively. RESULTS: Perceived vocal exertion, lightheadedness, and subjective laryngeal diadochokinetic difficulty increased as back pressure increased. Number of intervals completed, auditory-perceptual diadochokinetic strength, and participant rankings of back pressure conditions, by contrast, decreased as back pressure increased. 0 and 5 cm H2O were the most preferred back pressure conditions overall. DISCUSSION: Fluid back pressure was feasible and broadly tolerated during 15-minute trials of vocal exercise. However, the transition from 5 → 10 cm H2O appeared to represent an inflection point in our results: a minority of participants did not tolerate exercise at 10 cm H2O, becoming a majority at 15 cm H2O. We conclude that fluid back pressure should be restricted to values between 0 and 10 cm H2O during LDDK.

20.
Sci Rep ; 14(1): 15294, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38961120

ABSTRACT

Reliability mapping of 5G low orbit constellation network slice is an important means to ensure link network communication. The problem of state space explosion is a typical problem. The deep reinforcement learning method is introduced. Under the 5G low orbit constellation integrated network architecture based on software definition network (SDN) and network function virtualization (NFV), the resource requirements and resource constraints of the virtual network function (VNF) are comprehensively considered to build the 5G low orbit constellation network slice reliability mapping model, and the reliability mapping model parameters are trained and learned by using deep reinforcement learning, solve the problem of state space explosion in the reliability mapping process of 5G low orbit constellation network slices. In addition, node backup and link backup strategies based on importance are adopted to solve the problem that VNF/link reliability is difficult to meet in the reliability mapping process of 5G low orbit constellation network slice. The experimental results show that this method improves the network throughput, packet loss rate and intra slice traffic of 5G low orbit constellation, and can completely repair network faults within 0.3 s; For different number of 5G low orbit constellation network slicing requests, the reliability of this method remains above 98%; For SFC with different lengths, the average network delay of this method is less than 0.15 s.

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