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A series of laboratory experiments was performed to investigate the hydraulic performance of stormwater inlets. The results indicate that at the transition regime and for the maximum street slope, the addition of the second inlet increased the inlet discharge by 52% and 72% for cross-slopes of 2% and 4%, respectively. The normalized inlet discharge decreased non-linearly with the approaching water head in the weir flow regime while it linearly increased in the orifice flow regime. The effect of street slope was more pronounced in the orifice flow regime and prediction models were proposed to estimate inlet discharge for different road grades and cross-slopes. The boundary between weir and orifice flow regimes was identified for each stormwater inlet design and it was found that the cross-slope shifted the boundary more towards the orifice flow regime. It was observed that the peak efficiency decreased with increasing road grade. [ABSTRACT FROM AUTHOR]

In recent years, climate change and urbanization have become major concerns for developing countries, and this will continue to exacerbate in the future. It has triggered abundant challenges, among which urban flooding is becoming one of the most important. In this study, the impact of extreme rainfall on urban drainage systems is analyzed through a case study of Rohtak City in Haryana, India. For the study, a MIKE+ one-dimensional hydrodynamic and rainfall-runoff model was adopted. The monsoon rainfall data, from June to September 2022, was retrieved from India-WRIS and incorporated into MIKE+ as a time series for the simulation of rainfall-runoff. The main objectives of the study were to assess urban flood vulnerability zones and to identify individual hotspot nodes of existing drainage networks. Flooding from extreme rainfall and future rainfall increased due to climate change by 10% (Rainfall; R1), 20% (Rainfall; R2) and 50% (Rainfall; R3) because of the monsoon rainfall. Along with extreme event analysis, predictive analysis was also made. The hydraulic parameter for water level in nodes and pipes was used to determine the hydraulic capacity of the drainage system. The simulation results indicated that the city's drainage system became hydraulically inefficient in dealing with the extreme rainfall event in 2022 that caused urban flooding. For the studied drainage system, 52 overflooding nodes, 57 pressurized links, and 07 critical catchments were found to be vulnerable, which is 9.13% of the total catchment area. Validation of the extreme rainfall event simulated in MIKE+ was done by obtaining a flood extent map using Google Earth Engine with the help of SENTINEL-1 SAR imagery data. The accuracy of the MIKE+ model is analyzed using two parameters, i.e., percentage flooded areas and pixel percentage flooded. The MIKE+ model performed significantly well in determining percentage flooded areas with an accuracy of 79.66%. When using predictive analysis, the MIKE+ model provides a great insight into R3 time series rainfall showing 22.38% of the total sub-catchment area to be flooded when a rainfall intensity of R3 occurs. Remedies to this drainage failure could be either redesigning the drainage system or designing sustainable detention ponds. [ABSTRACT FROM AUTHOR]

To improve productivity, extensive agricultural areas in the Midwest United States require drainage systems consisting of subsurface drainage (tile) and open ditches. Transport of sediment, pathogens, pesticides, and nutrients from runoff and drainage from crop fields contributes to eutrophication and degradation of surface waters. Solutions are needed to improve environmental quality and reduce the negative impacts from runoff and agricultural drainage systems. This study assessed the effect of low-grade weirs on discharge and nitrate-nitrogen concentration and loss from a pair of experimental drainage ditches. One control (without weirs) and one treatment (with weirs) ditch were studied from 2017 through 2023 at the University of Minnesota, Southwest Research and Outreach Center near Lamberton, MN, United States. This study was the first evaluation of agricultural ditches, with and without low-grade weirs, and their potential to mitigate discharge and nitrogen loss in a cold climate. Stage-discharge data were collected using a data logger and bubble level sensor. Water samples were collected for water quality analysis daily using automated samplers. Analysis of the data was conducted using paired t-tests and a paired analysis approach. Analysis of covariance and linear regression of the treatment ditch against the control ditch were highly significant for nitrate-nitrogen concentration and load. The ditch with the low-grade weir was found to significantly decrease nitrate-nitrogen concentration and load. More specifically, the treatment ditch reduced discharge, nitrate-nitrogen concentration and load by 51%, 22% and 58%, respectively. The greatest discharge from the ditches occurred in March while most nitrogen losses occurred between May and June. This study provides evidence and highlights the potential of ditches equipped with low-grade weirs to reduce nitrate-nitrogen losses when compared to ditches without low-grade weirs in a cold climate. In addition, the study also emphasizes the importance of climate as a driver of nitrate-nitrogen loss from crop lands and ditches which is amplified by monthly precipitation variability. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to investigate the effects of different practices regarding tourniquet release timing and drain usage in primary total knee arthroplasty (TKA) on intraoperative and post-operative blood loss, operative time, and post-operative complications. Methods: A retrospective review was conducted on the records of patients who underwent TKA by one of four authors (E.Ö., S.Y., F.E.M., S.A.A.) from 01.09.2023 to 01.11.2024. Patients were divided into three groups: group A, early tourniquet release without drain use (E.Ö.); group B, early tourniquet release with drain use (F.E.M.); group C, late tourniquet release with drain use (S.A.A. and S.Y.). Patients with revision TKAs or use of constrained prosthesis, or removal of hardware were excluded. A total of 102 patients were identified. Demographic, blood loss, and operative time data were collected. The groups were compared regarding changes in preand post-operative hemoglobin (Hb) levels, operative times, and post-operative complications. Results: No significant differences in age, gender distribution, or pre-operative and post-operative Hb levels were observed between the groups (p>0.05). All groups showed a significant decrease in post-operative Hb levels compared with pre-operative values (p<0.05), but the Hb change was not statistically different between groups (p>0.05). The operative time was significantly longer in group B (122.0±18.6 minutes) than in groups A (101.0±14.3 minutes) and C (97.6±21.5 minutes) (p<0.05). Wound complications included prolonged wound drainage in group A, acute infection in group B, and superficial infection in group C, with no significant differences in complication rates between groups (p>0.05). Conclusion: Our results showed that different tourniquet release timings and drain use did not significantly impact perioperative blood loss but may affect the operative time. Specifically, drain use and early tourniquet release were associated with longer operation times. These findings suggest that late tourniquet release minimizes the operative time while maintaining comparable blood loss. This approach may be particularly beneficial in busy surgical settings where reducing operative time is a priority, without compromising patient safety or clinical outcomes. [ABSTRACT FROM AUTHOR]

Bottom vacuum preloading (BVP) is the method of applying vacuum pressure at the bottom zone of soils to generate pore-water pressure difference between the top and bottom boundaries, thereby achieving the consolidation drainage. This study conducted a large-size model test to explore the engineering feasibility of combining self-weight and BVP to treat construction waste slurry (CWS). Through the treatment of the measures of self-weight consolidation (0–26 d) and BVP with a water cover (26–78 d), the average water content of CWS declined from 255.6% to 115.9%, and the volume reduction ratio reached 0.476. However, since these two measures could properly treat only the bottom CWS, the measures of BVP with the mud cover (78–141 d) and the natural air-drying (141–434 d) were performed to further decrease the CWS water content near the upper zone. The latter two-stage measures reduced the average water content of CWS to 84.9% and increased the volume reduction ratio to 0.581. Moreover, the measurements suggested that the treated CWS largely exhibited a shear strength of 10 kPa or more. Overall, the proposed approach appeared some engineering feasibility to treat CWS, and the performed test study could act as a reference for the practical treatment of CWS. • Treatment mechanisms of CWS under self-weight and BVP were introduced in detail. • A first large-size model test for treating CWS under self-weight and BVP was conducted. • Total volume reduction ratio of CWS had reached 0.581 after the large-size model test. • Treatment method of combining self-weight and BVP exhibited some engineering feasibility. [ABSTRACT FROM AUTHOR]

This article from the Journal of Neurological Surgery. Part B. Skull Base showcases a video demonstrating the contralateral nasofrontal trephination (CNT) approach for treating a meningoencephalocele in the lateral recess of the sphenoid sinus. The procedure was performed on a 52-year-old female with a history of clear nasal drainage, resulting in excellent access to the lesion with minimal complications. The postoperative outcomes were positive, with no cerebrospinal fluid leaks and satisfactory cosmetic results. [Extracted from the article]

Drainage is a common practice in geotechnical engineering concerning dredged marine soils. Current drainage techniques, including surcharge preloading, vacuum preloading, and combined vacuum-surcharge preloading, have been proven to be effective in soft soil treatment, but are also criticized for their high energy consumption. This paper made a brief review on existing drainage techniques and proposed some prospects for the next-generation techniques in response to the public concern of sustainability. It is found that all conventional preloading techniques have been well studied from tests to modeling, and improved vacuum preloading tends to be used in combination with other techniques. Drainage techniques with lower energy consumption can be realized either by using renewable energy or designing biomimetic devices. The paper is expected to provide a comprehensive while concise report on recent advances in drainage techniques for dredged marine soils and in the meanwhile give an insight into the further development towards a more sustainable future. [ABSTRACT FROM AUTHOR]

Urban pluvial floods are characterised by a number of features such as the high spatial and temporal resolution needed to capture their dynamics, the complexity of dual drainage systems and the lack of sewer data availability, which make them very different from other types of floods, like coastal or fluvial floods, and which increase the difficulty of modelling them. As a consequence, most flood management plans do not include a rigorous evaluation of urban pluvial flood risk. In this paper, we give a comprehensive view of the current state of urban pluvial flood modelling, not restricted to a mere description of the mathematical approaches, but also including the most relevant features that should be considered in their modelling, the validation studies that have been performed to date and our vision on the modelling challenges that should be addressed in the near future. [ABSTRACT FROM AUTHOR]

We investigated the impact of water table (WT), monthly temperature, and precipitation of current and previous growing seasons on annual diameter growth of Scots pine in boreal drained peatlands. The data were collected from six sites across Finland. WT was monitored during 5–8 growing seasons depending on site during 2007–2014. The sites contained altogether 19 sample plots, where diameter growth from 339 trees was measured, resulting in 1599 growth observations. Tree-level diameter growth was analysed using mixed linear models, including variables describing tree size, competition, and environment. The higher precipitation in June of the previous year and May of the current year increased diameter growth, whereas the higher temperature in July of the current year and the deeper WT in August of the previous year decreased growth. The results suggest that Scots pine grows better at shallow than deep WT in drained peatlands. This contradicts earlier findings that a deep WT is needed to support tree growth in drained peatlands. We suggest that the development of a mor layer on the peat is changing nutrient cycling and hydrology. The results encourage the avoidance of intensive drainage in forested peatlands, which may also diminish the adverse environmental impacts of peatland forestry. [ABSTRACT FROM AUTHOR]

This paper conducts a small-scale hydraulic experiment and uses numerical simulation to jointly investigate the relationship between kitchen pipe design parameters and Fat, oil and grease (FOG) deposits when using food waste disposers (FWDs). In the experiment, the amount of pipe deposition is measured to evaluate the impact of different slopes and U-bend and 90° bend. The deposition rates and positions are assessed for four slopes and elbows in the simulation. At a flow rate of 1.0 L/s and a slope of 1.20%, the adhesion amount of FOG deposits is maximum. U-bend has the greatest effect on the adhesion of the deposits while 90° bend is minimal. The deposition rate will rise with higher slope and flow rate. New design parameters are proposed, including that the most effective slope is 0.40% within the range of 0.40%-4.80%, the appropriate use of 90° bend and P-bend, and the optimum cleaning time. [ABSTRACT FROM AUTHOR]

The South American Transcontinental Drainage Divide (TDD) is roughly oriented NE-SW from its Atlantic termination in SE Brazil to its NW termination in the limits between the southwestern edges of the Amazon Craton and the Andean Foreland. Based on a weak spatial coincidence with 90 − 70 Ma igneous intrusions, the origin and stability of the TDD have been attributed to intraplate magmatic activity. Using geomorphic analysis of drainage divides, we infer an overall southward migration of the TDD, even in areas with constrained uplift associated with intrusions. Most of the TDD is also the main drainage divide of the Paraná River Basin (PRB). Our analysis of the PRB divides reveals wholesale basin shrinkage, consistent with the southward migration of the TDD. We infer that the basalts of the Serra Geral Group induce topographic inversion of the PRB. Additionally, the PRB's thicker continental crust contributes to its higher elevation. Non-uniform dynamic subsidence rates since 50 Ma likely lowered relief in the basin headwaters near the TDD and enhanced across-divide relief asymmetry. Together, these internal and external factors keep the PRB elevated, with low relief, and make it topographically vulnerable to long-term drainage area loss. These base-level controls explain the position and mobility of the TDD. [ABSTRACT FROM AUTHOR]

Drainage pipelines face significant threats to underground safety due to external defects. Ground Penetrating Radar (GPR) is a primary tool for detecting such defects from within the pipeline. However, existing methods are limited to single or multiple axial scan lines, which cannot provide the precise spatial coordinates of the defects. To address this limitation, this study introduces a novel GPR-based drainage pipeline inspection robot system integrated with multiple sensors. The system incorporates MEMS-IMU, encoder modules, and ultrasonic ranging modules to control the GPR antenna for axial and circumferential scanning. A novel Cross-Line Fusion of GPR (CLF-GPR) method is introduced to integrate axial and circumferential scan data for the precise localization of external pipeline defects. Laboratory simulations were performed to assess the effectiveness of the proposed technology and method, while its practical applicability was further validated through real-world drainage pipeline inspections. The results demonstrate that the proposed approach achieves axial positioning errors of less than 2.0 cm, spatial angular positioning errors below 2°, and depth coordinate errors within 2.3 cm. These findings indicate that the proposed approach is reliable and has the potential to support the transparency and digitalization of urban underground drainage networks. [ABSTRACT FROM AUTHOR]

Background: Endoscopic ultrasound-guided transmural drainage (EUS-TD) is widely performed to treat postoperative peripancreatic fluid collection (POPFC). Recent reports on EUS-TD lack a consensus on stent selection. This study aimed to assess the efficacy of EUS-TD for POPFC using an external drainage-based approach. Methods: We retrospectively examined the medical records of patients with POPFC treated with EUS-TD using external drainage from October 2016 to July 2024. Technical success was defined as successful placement of the external drainage. Clinical success was defined as the reduction in fluid collection, as evidenced by follow-up computed tomography 1 week post-procedure. Results: This study included 14 patients. The median duration from surgery to endoscopic treatment was 13 (range: 11–26) days. The median procedural time was 26 (range: 13–35) min. The technical success rate was 100%, and 6 Fr endoscopic nasocystic drainage was performed in all patients. The clinical success rate was 100%, and no adverse events were observed. One patient experienced self-removal and required repuncture. Conclusions: EUS-TD for POPFC with an external drainage-based approach is safe and effective, with a short procedure time. However, this was a retrospective study with a small sample size, suggesting that future prospective studies are warranted. [ABSTRACT FROM AUTHOR]

The development of a city results in increased urbanization. This development leads to changes in land use in urban areas, creating large areas covered by buildings and roads, which reduces infiltration and increases surface runoff. With high rainfall of 147.238 mm per month, Sunyaragi Village often experiences flooding during the rainy season, especially on St. Taman Pemuda. This study aims to determine the number of infiltration wells needed to reduce the risk of flooding in Sunyaragi Urban Village, Cirebon City. The research employs descriptive methods using Arc-GIS remote sensing and quantitative methods, including hydrological analysis to measure rainfall intensity, hydraulics analysis to assess drainage channel capacity, and infiltration well analysis to determine the required number of infiltration wells. Based on the analysis results, the maximum runoff discharge value in the 5-year return period on St. Taman Pemuda is 0.00562 m²/sec, indicating that eight infiltration wells are needed. These wells are planned to be cylindrical, with a diameter of 1 m and a depth of 3 m, achieving an efficiency value of 85.04% in reducing runoff discharge. [ABSTRACT FROM AUTHOR]

The impact of a droplet onto another liquid is already a complex problem in which many forces are involved, but the problem becomes even more complex when an additional liquid layer is introduced. In this study, we report our investigation of the impact of water droplet on a thin oil layer (∼ 1 mm) atop water pool. As expected, the oil layer acts as a damper to the impact kinetic energy of the droplet, and the damping is greater as the viscosity of oil increases. We find that the damped energy is associated with the drainage of oil outward from the thin oil layer at the point of impact, i.e., viscous dissipation. To rationalize this observation, we introduce an analytical model that approximates the amount of viscous dissipation based on the volume displacement of oil by impact, defined by the cavity growth rate. Here, we introduce a parameter called the oil layer volume conservation factor and validate the equation indirectly, as the calculated values of this factor fall within the range of experimental values. [ABSTRACT FROM AUTHOR]

Background/Aims: To date, only thinner-diameter metal stents have been evaluated for unresectable malignant distal biliary obstruction (UR-MDBO). This study investigated the outcomes and optimal cohorts for a 6-mm-diameter fully covered self-expandable metal stent (FCSEMS) compared with those for a 10-mm-diameter FCSEMS. Methods: This single-center retrospective cohort study included patients who underwent initial transpapillary metal stenting for UR-MDBO. Propensity score matching (1:1) analysis was performed. Results: Of 133/68 patients who underwent 6-mm/10-mm-diameter FCSEMS deployment, 59 in each group were selected. The median time to recurrent biliary obstruction was not significantly different between the groups (p=0.46). In contrast, use of the 6-mm-diameter FCSEMS resulted in a significantly reduced incidence of stent-related adverse events (AEs) (p=0.016), especially cholecystitis (p=0.032), and patients aged <70 years were particularly affected by this significant reduction. Among the patients in the end-stage cohort who were unable to continue chemotherapy after FCSEMS deployment, the free rate of stent-related events, including recurrent biliary obstruction and stent-related AEs, was significantly higher in the 6-mm group (p=0.027). Conclusions: For UR-MDBO, a 6-mm-diameter FCSEMS can be an optimal and safe option in the younger cohort with a relatively high risk of AEs and in the end-stage cohort requiring safer drainage without interference from stent-related events during times of poor prognosis. [ABSTRACT FROM AUTHOR]