Search Results (69)

To explore the effects of different plant combinations in ecological floating beds on water quality purification and phytoplankton community structure in shallow eutrophic lakes, we conducted a survey of phytoplankton communities within ecological floating beds featuring distinct plant combinations in Meiliang Bay, Lake Taihu, during June and August 2021. The study focuses on two combinations: EA (Canna indica + Acorus calamus + Phragmites australis) and ES (Canna indica + Oenanthe javanica + Sagittaria sagittifolia). Results indicated that ecological floating beds significantly improved water quality, with the strongest restoration effects observed in the EA area. Specifically, turbidity was reduced by 47–89%, while chlorophyll a (Chl-a) concentration inhibition rates reached 82% in June and 54% in August. The comprehensive trophic state index (TLI) remained stable at levels indicating slight eutrophication (≤58.6). Phytoplankton community structure shifted from dominance by eutrophic functional groups (primarily FG M) toward greater diversity. In the EA area, the number of dominant functional groups increased from five (control) to six, and the abundance of the key cyanobacteria group (FG M) declined from 18.29% (control) to 7.86%. Redundancy analysis (RDA) revealed temporal changes in driving factors: nutrients were primary in June (explanation rate: 64.7%), while physical factors dominated in August (explanation rate: 51.2%). This study demonstrates that installing ecological floating beds with diverse plant combinations in shallow eutrophic lakes can effectively alter phytoplankton community structure and enhance in situ water restoration. Among the tested combinations, EA (Canna indica + Acorus calamus + Phragmites australis) exhibited the optimal restoration effect. These findings provide a scientific basis for water environment protection and aquatic biological resource restoration in shallow eutrophic lakes. Full article

Background/Objectives: Limited data exist on the organization and operation of Level II/III Neonatal Intensive Care Units (NICUs) in Greece; this retrospective cross-sectional survey explored their structure and functioning in 2004 and 2022. Methods: A structured questionnaire was utilized, along with demographic and perinatal data obtained from the Hellenic Statistical Authority. Results: Between 2004 and 2022, live births decreased by 28%, while the prematurity rate rose from 6.96% to 11.87% (p < 0.001). Significant regional differences were observed in the number of NICUs (p = 0.033), live births (p < 0.001), and NICUs per 10,000 live births (p = 0.025). In this survey, data from 20 Level III NICUs in 2004 and 22 NICUs (one Level II) in 2022 were analyzed. NICU admissions increased by 16.1% (p = 0.389), while the rate of admitted neonates/1000 live births increased from 13.5 to 21.8 (p < 0.001). In 2022, premature infants constituted 40.2% of NICU admissions. The number of board-certified neonatologists increased by 21.8% between 2004 and 2022 (p = 0.795), along with a rise in the ratio of neonatologists per 10,000 live births (from 14.8 to 25, respectively, p < 0.001). Conversely, there was a significant 17.2% reduction in the nursing staff by 2022 (p = 0.034). The number of available NICU beds also increased during the study period. The ratio of ventilators to intensive care beds significantly improved (p < 0.001). In 2022, new treatment modalities, like therapeutic hypothermia, were introduced, and most NICUs reported offering long-term follow-up programs. Conclusions: This survey highlights significant advancements in Level II/III NICU infrastructure and care capabilities, while emphasizing demographic changes and a critical shortage of neonatal nursing staff. These factors should be carefully considered by health authorities in the development of future neonatal care strategic planning in the country. Full article

This paper reports the results of a study on the significance of the inertization system configuration of a laboratory-scale fixed bed batch reactor with regard to the yield of pyrolysis oil and reactor conversion. Two typical reactor inertization systems were investigated depending on whether the carrier gas (nitrogen in this study) was added from the top or from the bottom of the reactor. Polypropylene (PP) packaging waste (100 g) was used as a model sample. A factorial experimental design was adopted for one categorical parameter, the arrangement of parts of the reactor inertization system. All experiments were conducted at 475 °C, with a carrier gas flow rate of 0.1 L/min and a reaction time of 90 min. Statistical analysis and processing of the results showed that the configuration of the inertization system had a remarkable impact on the pyrolysis oil and gas yield, while its impact on the overall reactor conversion was negligible. When applying the two observed methods of reactor inertization, the average yields of pyrolysis oil and gas differed by 1.7% and 1.8%, respectively. All of the applied statistical treatments had a significance level of 0.05, i.e., there was only a 5% chance of incorrectly rejecting the hypothesis of equality of arithmetic means of pyrolysis yields when the two different methods of reactor inertization were applied. The explanation of this behavior is attributed to the temperature change inside the reactor, which shows that this particular fixed bed reactor suffers from local overheating in its middle part. Local overheating of the middle part of the reactor is more pronounced in the case of inerting the reactor from the bottom, which leads to greater excessive cracking of volatile products compared to the mode of inerting the reactor from the top part and thus greater formation of non-condensable gases, i.e., a reduction in the yield of pyrolytic oil. Full article

River barrages ensure water availability for enhanced irrigation and human consumption. Of course, effective and sustainable management of existing barrages requires controlling riverbed erosion through appropriately designed stilling basins with their appurtenances. The present study assesses the stilling basin performance of the Taunsa Barrage, a vital water resources infrastructure built in 1958 in Punjab, Pakistan, and rehabilitated between 2004 and 2008 through the construction of a subsidiary weir (SW) downstream of the main weir. A physical modeling approach was employed, consisting of two distinct phases of laboratory experiments. Phase 1 replicated the Taunsa Barrage before rehabilitation, assessing the need for SW construction under different discharge rates and downstream bed elevations. Phase 2 reproduced the post-rehabilitation conditions, including varying discharge values, heights and positions of the SW, to evaluate the stilling basin design concerning the ability to dissipate flow energy. The results demonstrated (i) inadequate tailwater levels and oscillating hydraulic jump formation under increased discharges in pre-rehabilitation conditions (highlighting the poor performance of the original Taunsa Barrage stilling basin and the need for an SW to address these hydraulic deficiencies), and (ii) that the SW, under the design conditions, achieved optimal head loss for discharge values near the design discharge. However, the head loss efficiency was highly sensitive to variations in the distance and height of the SW due to hydraulic jump pulsations. Moreover, the head loss efficiency rapidly degraded for discharges greater than the design discharge. These findings indicate that the Taunsa barrage stilling basin may lack the capacity to accommodate higher discharges resulting from the interplay between climate change and land use alterations within the upstream Indus River basin. Future research should focus on developing a design that enhances energy dissipation robustness, reducing susceptibility to potential discharge increases. Full article

Most pier scour monitoring methods cannot be carried out during floods, and data cannot be recorded in real-time. Since scour holes are often refilled by sediment after floods, the maximum scour depth may not be accurately recorded, making it difficult to derive the equilibrium scour depth. This study proposes a novel approach using 16 proximity sensors (VCNL4200), which are low-cost (less than USD 3 each) and low-power (380 µA in standby current mode), to monitor and record the pier scour depth at eight different positions in a flume as it varies with water flow rate. Based on the regression relationship between PS data and distance, the scour trend related to the equilibrium scour depth can be derived. Through the results of 13 local live-bed sediment scour experiments, this PS module was able to record not only the scour depth, but also the development and geometry of the scour under different water flows. Additionally, based on PS data readings, changes in the topography of the scour hole throughout the entire scouring process can be observed and recorded. Since the maximum scour depth can be accurately recorded and the scour trend can be used to estimate the equilibrium scour depth, observations from the experimental results suggest that the critical velocity derived by Melville and Coleman (2000) may have been underestimated. The experimental results have verified that, beyond achieving centimeter-level accuracy, this method also leverages the Internet of Things (IoT) for the long-term real-time observation, measurement, and recording of the formation, changes, and size of scour pits. In addition to further exploring scouring behavior in laboratory studies, this method is feasible and highly promising for future applications in on-site scour monitoring due to its simplicity and low cost. In future on-site applications, it is believed that the safety of bridge piers can be assessed more economically, precisely, and effectively. Full article

Hypokinesia triggers oxidative stress and accelerates the turnover of the glutathione system via the γ-glutamyl cycle. Our study aimed to identify the regulatory checkpoints controlling intracellular glutathione levels. We measured the intermediate substrates of the γ-glutamyl cycle in erythrocytes from 19 healthy young male volunteers before and during a 10-day experimental bed rest. Additionally, we tracked changes in glutathione levels and specific metabolite ratios up to 21 days of bed rest. Using gas chromatography-mass spectrometry and the internal standard technique, we observed a 9 ± 9% decrease in glutathione levels during the first 5 days of bed rest, followed by an 11 ± 9% increase from the 5th to the 10th day, nearly returning to baseline ambulatory levels. The cysteinyl-glycine-to-glutathione ratio, reflecting γ-glutamyl cyclotransferase activity (a key enzyme in glutathione breakdown), rose by 14 ± 22% in the first 5 days and then fell by 10 ± 14% over the subsequent 5 days, again approaching baseline levels. Additionally, the γ-glutamyl cysteine-to-cysteine ratio, indicative of γ-glutamyl cysteine synthetase activity (crucial for glutathione synthesis), increased by 12 ± 30% on day 5 and by 29 ± 41% on day 10 of bed rest. The results observed on day 21 of bed rest confirm those seen on day 10. By calculating the ratio of product concentration to precursor concentration, we assessed the efficiency of these key enzymes in glutathione turnover. These results were corroborated by directly measuring glutathione synthesis and degradation rates in vivo using stable isotope techniques. Our findings reveal significant changes in glutathione kinetics during the initial days of bed rest and identify potential therapeutic targets for maintaining glutathione levels. Full article

Changes in land usage, increasing climatic uncertainty, and dynamic development of the rate of natural population growth of the Eurasian beaver will lead to increasing benefits and disadvantages from beaver activity. During three growing seasons from 2020 to 2022, four cross-sections were marked on unused sub-irrigation systems with the periodic occurrence of beaver dams, located on organic soils in parts of the facility protected by the Habitats Directive (natural habitat 6510) in Central Poland. Periodic water table measurements in wells, the beds of adjacent ditches, and the riverbed were carried out. Identification of the states and structures of plant communities was done using the botanical-weight analysis of several samples with an area of 1 m². Beaver dams increased water levels in the river, ditches, and groundwater depth in over 78% of events in 2020–2022 years. A large impact of precipitation on the hydraulic conditions in the meadow was observed. In the studied area, since a moderately moist habitat (6510) is protected within the Natura 2000 network, phenomena increasing soil moisture, in the absence of mowing of meadows and the occurrence of expansive herbaceous vegetation that tolerates increased moisture, may lead to the disappearance of these habitats, especially in the zone near the riverbed. Full article

Seasonal changes, sea level rise, and global warming make flood events more frequent, which necessitates watershed management and efficient use of water resources. In this context, understanding the hydrodynamic behavior of basins is critical for the development of flood prevention strategies. The contributions of hydrological and hydraulic modeling techniques in this process are among the key determinants of sustainable water resources management. The Filyos Sub-Basin, located in the Western Black Sea Basin, stands out as one of the regions where flood risk assessment is a priority, as it has two important floodplains. This study aims to analyze the flood risk in the Filyos River Sub-Basin with hydraulic modeling methods, and to determine the Manning roughness coefficient. In the study, the parameters affecting the roughness of the river bed were analyzed using the Cowan method, and the effects of vegetation on river bed resistance were evaluated in the laboratory environment. Flood simulations were carried out for four different flow rates (Q₁₀₀₀, Q₅₀₀, Q₁₀₀ and Q₅₀) using the HEC-RAS model, and the performance of flood protection structures were analyzed. The findings show that a significant portion of the existing protection structures are unable to meet the potential flood flows, which can cause serious damage to residential and agricultural areas. In basins with limited historical discharge data, such as the Filyos River, these findings provide important contributions to sustainable water resources management and regional planning processes. The results of the study serve as a reference for flood risk assessment, not only for the Filyos River Basin, but also for other basins with similar hydrodynamic characteristics. It is envisaged that future research, supported by larger data sets, can improve the accuracy of flood simulations. Furthermore, the Cowan method and HEC-RAS model used in this study are expected to contribute to strategic planning and engineering solutions to minimize flood risk in other watershed management projects. In future studies, we plan to further develop methodological approaches for determining the roughness coefficient, and to address applications to increase the effectiveness of flood protection structures. Full article

Purpose: To analyze the clinical efficacy of superselective renal artery embolization and retroperitoneal laparoscopic partial nephrectomy for the treatment of ruptured hemorrhagic renal angiomyolipoma and to provide a reference for the selection of treatment methods for ruptured hemorrhagic renal angiomyolipoma. Methods: A retrospective analysis was conducted on the clinical data of 24 patients who were diagnosed with ruptured hemorrhagic renal angiomyolipoma at the Second Hospital of Tianjin Medical University between January 2019 and December 2021. Among them, 10 patients were treated with superselective arterial embolization (SAE), and 14 patients were treated with retroperitoneal laparoscopic part nephrectomy (RLPN). The differences between the two treatment methods in terms of hospital stay, hospital costs, anesthesia method, operation time, intraoperative blood loss, postoperative bed rest time, antibiotic dosage, postoperative complication rate, tumor diameter changes, creatinine value changes, hemoglobin value changes, tumor recurrence rate, and reoperation rate were compared. Results: All patients completed the treatment and were discharged. There were no significant differences in length of hospital stay, hospital costs, creatinine change values, or postoperative complication rates between the two groups (p > 0.05). However, there were statistically significant differences (p < 0.05) in surgical time (85.50 ± 19.94 min vs. 141.07 ± 76.33 min), intraoperative blood loss (21.50 ± 14.72 mL vs. 153.57 ± 97.00 mL), postoperative bed rest time (22.7 ± 1.56 h vs. 41.21 ± 3.57 h), preoperative hemoglobin levels (94.7 ± 23.62 g/L vs. 113.79 ± 17.83 g/L), and hemoglobin changes (−6.60 ± 10.36 g/L vs. −15.21 ± 8.79 g/L) between the two groups. Both groups of patients had an average follow-up period of 22 months, and patients in the SAE group had a mean reduction of 3.33 cm in tumor diameter within the follow-up period compared with the pre-embolization period (p < 0.05). None of the patients in the SAE group experienced rebleeding, and there was no tumor recurrence in either group. Conclusion: SAE and RLPN are effective treatments for ruptured renal angiomyolipoma with good outcomes. Furthermore, compared to RLPN, SAE offers advantages such as simplicity of operation, minimal trauma, shorter surgical time, minimal impact on hemoglobin levels, shorter bed rest time, faster postoperative recovery, and maximal preservation of renal units. Full article

Coastal backwater effects on low-gradient coastal plain rivers extend well upstream of the head of the estuary and propagate upstream as sea-level rises. Hydrological, geomorphological, and ecological indicators can serve as sentinels of the upriver encroachment. Analyzing the along-river spatial distribution of these indicators as a space-for-time substitution allows the prediction of sequential changes. Interpretation of results from 20 rivers in Virginia and the Carolinas shows that backwater effects at the leading edge result in higher river stages, increasing floodplain inundation, and raising water tables. Lower slopes and flow velocities reduce sediment transport, reducing river sediment input and floodplain deposition. This inhibits natural levee development, reducing bank heights. These factors combine to increase the frequency and duration of inundation, resulting in semi-permanently flooded wetlands. Anaerobic conditions limit organic decomposition, and ponding allows transported and suspended organic matter to settle, leading to organic muck and peat floodplain soils. This accumulation, coupled with general valley-filling, buries alluvial terrace remnants. Finally, vegetation changes driven by salinity increases occur, resulting in swamp conversions to brackish marsh. Backwater encroachment is strongly controlled by channel bed slope, with relatively steeper channels experiencing slower rates of tidal extension. With accelerating sea-level rise (SLR), the lowest-sloping channels could experience encroachment rates of >1 km yr⁻¹. Hydrological changes associated with SLR are most rapid at the leading, upriver end—averaging 71 km upstream of the head of the estuary in the study rivers at present—and at the lowermost, downstream end of the fluvial-estuarine transition zone. Full article

Three models/methods are given to understand the extreme international variation in available and occupied hospital bed numbers. These models/methods all rely on readily available data. In the first, occupied beds (rather than available beds) are used to measure the expressed demand for hospital beds. The expressed occupied bed demand for three countries was in the order Australia > England > USA. Next, the age-standardized mortality rate (ASMR) has dual functions. Less developed countries/regions have low access to healthcare, which results in high ASMR, or a negative slope between ASMR versus available/occupied beds. In the more developed countries, high ASMR can also be used to measure the ‘need’ for healthcare (including occupied beds), a positive slope among various social (wealth/lifestyle) groups, which will include Indigenous peoples. In England, a 100-unit increase in ASMR (European Standard population) leads to a 15.3–30.7 (feasible range) unit increase in occupied beds per 1000 deaths. Higher ASMR shows why the Australian states of the Northern Territory and Tasmania have an intrinsic higher bed demand. The USA has a high relative ASMR (for a developed/wealthy country) because healthcare is not universal in the widest sense. Lastly, a method for benchmarking the whole hospital’s average bed occupancy which enables them to run at optimum efficiency and safety. English hospitals operate at highly disruptive and unsafe levels of bed occupancy, manifesting as high ‘turn-away’. Turn-away implies bed unavailability for the next arriving patient. In the case of occupied beds, the slope of the relationship between occupied beds per 1000 deaths and deaths per 1000 population shows a power law function. Scatter around the trend line arising from year-to-year fluctuations in occupied beds per 1000 deaths, ASMR, deaths per 1000 population, changes in the number of persons hidden in the elective, outpatient and diagnostic waiting lists, and local area variation in births affecting maternity, neonatal, and pediatric bed demand. Additional variation will arise from differences in the level of local funding for social care, especially elderly care. The problems associated with crafting effective bed planning are illustrated using the English NHS as an example. Full article

The objective of this study was to assess the growth rates and general body condition of two common game fishes (largemouth bass Micropterus nigricans and bluegill Lepomis macrochirus) in a productive midwestern USA lake, Lake Winona, 20+ years after one of its two separate basins was partially dredged. We also used historical lake survey data spanning 19 years before and 15 years after dredging to assess the pre- and post-dredging growth of these species. Dredging was expected to improve the growth rates and conditions (relative weights) of both species due to post-dredging changes to lake habitats (more open water and reduced macrophyte beds) and the fish community structure in the dredged basin. Both species displayed significantly faster growth in the dredged basin, with the bluegill by age 3 and the bass by age 6. The mean relative weights of both species were significantly higher in the non-dredged basin (bass were in good condition: 106% versus 100%; bluegill were in fair condition: 84% versus 80%), although both bluegill and largemouth bass exhibited significant declines in relative weight with increasing lengths in the non-dredged basin. The growth rates for largemouth bass have declined from historical levels, especially in the non-dredged basin, whereas bluegill growth rates have remained stable or improved, especially in the dredged basin. Overall, largemouth bass and bluegill growth rates and relative weights are responding to differences in habitat and fish communities between dredged and non-dredged basins, indicating that the two lake basins are isolated enough from one another to allow for separate biological responses to occur in each. Full article

Monitoring of IAQ is one of the foundations of the preventative actions prompted by the worldwide recognition of COVID-19 transmission. The measurement of CO₂ has emerged as one of the most popular, dependable, and easy ways to indirectly evaluate the state of indoor air renewal. Reducing the risk of respiratory diseases transmitted by aerosols is attainable through implementing and validating prevention measures made possible by CO₂ control. Isolation centers are like health facilities in that they are linked to IAQ, and the presence of natural ventilation can significantly improve the circulation of fresh air, which speeds up the removal of contaminants. This is true even though healthcare facilities are among the environments with the highest rate of COVID-19 propagation. Our investigation revealed, however, that no substantial critical data on air quality in Tanzanian isolation centers is presently available. The process of metabolic CO₂ creation and accumulation within health isolation center cubicles was investigated in this study. Crucially, we suggest comparing settings under various conditions using the indicator ppm/patient. In this research, we experimentally assessed the value of changing a few HVAC system characteristics. We looked at the data to see how well the filtration system worked concerning the submicron particle concentration. Study recommendations for CO₂ detectors and ways to reduce infection risk in shared isolation center cubicles are provided. We also show the correlation between particle size and CO₂ concentration, the correlation between CO₂ concentration derivatives and air volume presented per patient in isolation cubicles, the correlation between patient occupancy and CO₂ concentration levels in isolation cubicles, and how to improve air quality by adjusting the patient’s bed position. The study also found that for exposure lengths of two to three hours, a typical hospital cubicle with fifty to one hundred people should have an average interior CO₂ value of less than 900 ppm. Carers’ length of stay in the hospital substantially impacted the permissible CO₂ concentration. By establishing a connection between indoor air monitoring and healthcare goals, this study will aid in determining the feasibility of establishing regulations for interior CO₂ content depending on occupancy settings, strengthening preventive efforts against COVID-19. In the post-pandemic era, it will be essential to find ways to make health facilities air cleaner so that infectious diseases cannot spread in the future. Full article

When there is vegetation on the beach or main channel bed, it will have a significant impact on the river channel. This study was based on physical model experiments to investigate the flow conditions of the Jinhu section of the Huaihe River estuary, revealing the influence of reed vegetation on water flow resistance. A new comprehensive roughness formula was proposed, and the predictive effectiveness of the formula was verified. The theoretical results indicate that under the condition of vegetation not being submerged, the comprehensive roughness is directly proportional to the square root of vegetation density in areas with vegetation coverage, the square root of water surface vegetation coverage, and the 2/3 power of the hydraulic radius. The bottom slope does not affect it. Under the condition of vegetation inundation, the comprehensive roughness is smaller than that under the condition of no inundation. The experimental prediction results of the influence of reeds on roughness indicate that the measured roughness values and theoretical roughness calculation values are in good agreement. Under the same operating conditions, the roughness gradually decreases with an increase in flow rate. Under the full-reed working condition, the calculated roughness value and the measured roughness value have the same trend of change, both decreasing with the increase in flow rate. The experimental prediction results of the influence of reeds on the relationship between water level and flow rate show that the roughness value of 0 increases with the increase in reed grass surface coverage rate K_i, and an increase in K_i can lead to an increase in comprehensive roughness. Full article

In this study, laboratory experiments were conducted to investigate the influence of changes in storm wave height and water level on beach response in a medium-scale wave flume. A schematic storm was simulated (rising, apex, and waning phases). A non-intrusive photogrammetric method was used to collect high-resolution and synchronous data regarding the free surface water elevation and bed level, from which shoreline location, sandbar position, cross-shore sediment transport rates, and nonlinear wave parameters were derived. The cross-shore sediment transport was in agreement with previous laboratory measurements, including the monotonous exchange from foreshore erosion to shoaling zone accretion in most stages of the storm simulation. The surf zone was the main region supplying sediment for beach morphology modification and sandbar generation. The degree of storm erosion was not completely determined by the largest wave height and water level or the cumulative wave power of the apex phase. The largest gradients of the wave parameter sequence change occurred in the rising phase, and this was the main factor generating efficient beachface erosion. It induced an increase in sandbar size, accompanied by the cross-shore motion of maximum velocity amplitude, more violent disturbances of wave nonlinearity, and increased surf zone erosion, with these factors increasing beach instability and leading to more severe storm erosion. The large wave height and water level resulted in shoreline retreat, with a more significant swash zone erosion under a higher runup. The offshore sediment transport turned toward the onshore direction as the original large sandbar deteriorated under the decreasing wave parameter sequence in the waning phase. Full article