Water Load Research Articles

Hydrological Changes and Sediment Dynamics in the Inner Mongolia Section of the Yellow River: Implications for Reservoir Management

The Inner Mongolia section of the Yellow River is a primary alluvial segment of the main channel. The variations in water and sediment not only alter the cross-sectional morphology and flow capacity of the river but also impact the scheduling of upstream cascade reservoirs. Based on runoff and sediment load data and topographic information from typical hydrological stations, the characteristics of runoff and sediment load variations and the evolutionary pattern of siltation in the Inner Mongolia River section were analyzed via trend analysis methods, Mann–Kendall test methods, the sediment load transport rate method, and the water level–flow relationship. The results showed that the water and sediment loads at the hydrological stations in the Inner Mongolia River section significantly changed from the 1960s to after 2000, with runoff decreasing by approximately 22% to 32% and the sediment load decreasing by approximately 65% to 73%. Sedimentation in the river section generally increased, and the average annual siltation amount reached 0.144 billion t. The joint utilization of the Longyangxia and Liujiaxia reservoirs in 1987 was the main reason for the rapid increase in siltation, and siltation in the Inner Mongolia River section was slightly reduced after 2005. In addition, the critical sediment load coefficients of the Bayangaole–Sanhuhekou and Sanhuhekou–Toudaoguai River sections were 0.0073 and 0.0051 kg·s/m6, respectively, from 1952 to 1968, and 0.0053 and 0.0037 kg·s/m6, respectively, from 1969 to 2020. This study could provide technical support for river flood control and reservoir water sediment regulation in Inner Mongolia.

Development of masked silica tanning system for sustainable leather production.

Amid mounting pressure on the long-term recyclability of chromium in tanned leather and the associated environmental hazards, the quest for an alternative, cleaner tanning system has gained tremendous momentum. In this context, our study explores the remarkable potential of silicates as a versatile platform for skin/hide tanning, circumventing the inherent risks and ecological threats posed by chromium exposure and leaching. We present an alternative approach of using a silica-based tanning system, employing a Taguchi model, to optimize a masked silica (MaSil) tanning product/process for achieving effective collagen stabilization. Our results demonstrate the significant advancements made in hydrothermal denaturation temperature, reaching an impressive 79 °C through precise Taguchi parameters-5% SiO2, masked with 0.3 mole of citrate salt, and a tanning process fixation pH of 4.5. Notably, the mechanical strength analysis reveals compliance with the stringent upper leather recommendation standards, validating the practicality and quality of MaSil crust leather. Moreover, our research highlights the unprecedented environmental benefits of the first reported application of Taguchi's approach to the MaSil tanning system. The developed tanning system remarkably reduces total dissolved solids (TDS), biological oxygen demand (BOD), chemical oxygen demand (COD), and overall water load by 68.4%, 25.4%, 59.5%, and 33.7%, respectively, heralding a promising era of water and environmental sustainability in the leather sector. This study holds the potential to transform leather production, wherein the envisioned future on the use of the Taguchi model and optimized MaSil tanning system could find a place in shaping a cleaner, greener, and more sustainable leather industry.

Effect of dynamic neuromuscular stabilization training using the inertial load of water on functional movement and postural sway in middle-aged women: a randomized controlled trial

BackgroundChronic stress and diseases occur more frequently in middle-aged compared to younger women and this is often the result of physical, psychological and socio-economic changes. These health consequences reduce lower body muscle mass and flexibility, leading to generalized impairments in functional movement and balance. Dynamic Neuromuscular Stabilization (DNS) training using the inertial load of water is known for its positive impact on functional strength improvement and muscle stabilization.ObjectiveThis study aimed to determine the effect of DNS training using inertial water loads on functional movement and postural sway in middle-aged women.MethodA sample of 24 middle-aged women participated in the study and were randomly divided into two groups: the experimental group, n = 12 (age: 58.33 ± 1.48 yrs, height: 162.16 ± 1.27 cm, weight: 61.77 ± 2.21 kg) and control group, n = 12 (age: 59.58 ± 1.13 yrs, height: 160.1 ± 1.13 cm, weight: 57.51 ± 1.12 kg). Center of Pressure (COP), moving distance, Root Mean Square (RMS), movement area and Functional Movement Screen (FMS) were conducted and analyzed pre- and post-examination. Participants engaged in the DNS training regimen, which utilized the inertial load of water, for 60 min each session, conducted twice weekly for 12 weeks.ResultsThere were significant differences in the COP distance (p < 0.001), RMS (p < 0.05), COP area and FMS test (p < 0.001) in the pre-post comparison of each group. And significant differences were found in COP distance (p < 0.05), RMS (p < 0.05), COP area (p < 0.05) and FMS test (p < 0.05) between groups. The DNS training improved the dynamic stability of single-leg standing, torso stability and functional movement in middle-aged women.ConclusionDNS training programs using the inertial load of water have been shown to be effective in movement improvement and posture retention ability, which is beneficial for functional movement, equilibrium strategy, and dynamic stability of middle-aged women. Furthermore, the DNS training method designed in this study can be useful for trainees who require posture correction in a safe and effective way regardless of their age and gender.

Sensitivity of GNSS‐Derived Estimates of Terrestrial Water Storage to Assumed Earth Structure

AbstractGeodetic methods can monitor changes in terrestrial water storage (TWS) across large regions in near real‐time. Here, we investigate the effect of assumed Earth structure on TWS estimates derived from Global Navigation Satellite System (GNSS) displacement time series. Through a series of synthetic tests, we systematically explore how the spatial wavelength of water load affects the error of TWS estimates. Large loads (e.g., &gt;1,000 km) are well recovered regardless of the assumed Earth model. For small loads (e.g., &lt;10 km), however, errors can exceed 75% when an incorrect model for the Earth is chosen. As a case study, we consider the sensitivity of seasonal TWS estimates within mountainous watersheds of the western U.S., finding estimates that differ by over 13% for a collection of common global and regional structural models. Errors in the recovered water load generally scale with the total weight of the load; thus, long‐term changes in storage can produce significant uplift (subsidence), enhancing errors. We demonstrate that regions experiencing systematic and large‐scale variations in water storage, such as the Greenland ice sheet, exhibit significant differences in predicted displacement (over 20 mm) depending on the choice of Earth model. Since the discrepancies exceed GNSS observational precision, an appropriate Earth model must be adopted when inverting GNSS observations for mass changes in these regions. Furthermore, regions with large‐scale mass changes that can be quantified using independent data (e.g., altimetry, gravity) present opportunities to use geodetic observations to refine structural properties of seismologically derived models for the Earth's interior structure.

Investigating the energy storage performance in optimal design of a solar hybrid multi‐generation system with distillatory

AbstractIn this study, a cogeneration system of heating, cooling and power used with the solar flat plate collectors (FPCs) and photovoltaic panels (PVs) integrates with a multi‐effect distillation through thermal vapor compression (MEE‐TVC), investigated as the first system to meet the loads of heating, cooling, electricity and fresh water. As an innovation, the combination of the first system with cooling and thermal storage tanks have been investigated. The systems are optimized with MATLAB and single‐objective genetic algorithm. The total annual cost considered as the objective function to compare the two systems and 36 and 61 design variables are obtained for the first and second systems, respectively. The design parameters considered for optimization included the capacity of the diesel engine as the prime mover, electrical chiller capacity, absorption chiller capacity, size of the boiler, partial loads of the diesel engine for each hour of the 2 days (1 day for hot months and 1 day for cold months), partial loads of the chillers for each hour of the first days (second day has no cooling load), number of FPCs and PVs, number of effects in the desalination unit, driving steam pressure, feed water flow rate, driving steam flow rate, and electric cooling ratio. The optimization aimed to fulfill the heating, cooling, electricity, and fresh water requirements of a residential town situated in Bandar Abbas, Hormozgan province, Iran. The second system's optimization results were compared with first system. The results have shown that the objective function for the first system was and the initial investment cost was , and for the second system the objective function was and the initial investment cost was . Therefore, by using energy storage, the objective function was reduced by 11.30%.

Elastic deformation as a tool to investigate watershed storage connectivity

Storage-discharge relationships and dynamic changes in storage connectivity remain key unknowns in understanding and predicting watershed behavior. In this study, we use Global Positioning System measurements of load-induced Earth surface displacement as a proxy for total water storage change in four climatologically diverse mountain watersheds in the western United States. Comparing total water storage estimates with stream-connected storage derived from hydrograph analysis, we find that each of the investigated watersheds exhibits a characteristic seasonal pattern of connection and disconnection between total and stream-connected storage. We investigate how the degree and timing of watershed-scale connectivity is related to the timing of precipitation and seasonal changes in dominant hydrologic processes. Our results show that elastic deformation of the Earth due to water loading is a powerful new tool for elucidating dynamic storage connectivity and watershed discharge response across scales in space and time.

Inclusion of the radiative effect of deep convective clouds in the Eta model simulations

AbstractConvective clouds play an important role in the local energy budget by directly interacting with solar and terrestrial radiation. However, radiation parameterization schemes of atmospheric models generally consider clouds produced from microphysics schemes or some other grid saturation criteria. Deep convective parameterization schemes tend to rain out the convective cloud before the radiation scheme perceives its water load. This may be a source of the positive bias of the incoming solar radiation at the surface. The objective of this work is to include the effects of deep convective clouds in the radiation scheme of the regional Eta model and to evaluate the impacts on the net radiative energy and other meteorological variables. The radiation scheme is the Rapid Radiative Transfer Model. The work is developed in four stages. The positive bias in the incoming solar radiation was diagnosed in the first stage. In the second stage, the parameters of the convective parameterization scheme were modified to increase convective precipitation. In the third stage, the parameters of the microphysics scheme were modified to increase explicit clouds. In the fourth and last stage, in addition to the previous modifications, the condensates from the convective parameterization were input into the radiation scheme. The runs were performed for a period of one summer rainy month with intense convective activity over South America. Including deep convective cloud condensates into the radiation scheme improved the cloud cover, the diurnal cycle of the surface net radiation, and the 2‐m temperature. However, the reduction of the net radiation at the surface caused the reduction of the available energy for convective instability and, consequently, the precipitation reduction. The results show the importance of including cumulus cloud water load in the radiative scheme for bias reduction in the radiative energy components.

Patterns of glacio‐isostatic adjustment in mainland Scotland: new data from western central Scotland, proximal to the zone of maximum rebound

The results of geomorphological mapping and survey of Lateglacial and Holocene displaced shorelines in the Clyde estuary and around Loch Lomond, western central Scotland are described. On the basis of morphology, sedimentology, altitude and radiocarbon dating, four discrete shorelines are identified and are correlated with previously identified Scottish displaced shorelines. The shoreline formerly referred to as the Main Postglacial Shoreline is renamed the Menteith Shoreline. This body of data, combined with data on displaced shorelines for Scotland as a whole has been analysed using Gaussian quadratic trend surface analysis in order to determine the centre of glacio‐isostatic displacement for each shoreline. These Gaussian models of palaeo‐relative sea‐level suggest that the zone of greatest displacement lay NNW of Loch Lomond in the Lateglacial then moved SSE to the region of Loch Lomond during the Holocene and the Clyde in the Late Holocene. The factors responsible for the movement of the zone of greatest uplift are discussed, including temporal variations in the ice‐sheet thickness, variations in water load in the adjacent sea‐lochs and neotectonic processes. Comparison is made with glacial isostatic adjustment (GIA) models. A sensitivity analysis has been carried out on the use of Gaussian trend surface analysis glacio‐isostatic modelling and this is included in the research evaluation, and reported in full in the Supporting Information files, along with the raw data used throughout this study.

LSTM-based deformation forecasting for additional stress estimation of existing tunnel structure induced by adjacent shield tunneling

A redistribution of stress is caused by the excavation of a new tunnel within the soil surrounding the existing shield tunnel structure. This stress redistribution results in alterations to the soil and water loads around the existing tunnel structure, ultimately impacting its stress and deformation. The deformation response of existing tunnels is primarily focused on in most existing studies, with limited research conducted on the coupling system of new tunnel excavation, soil stress state, and deformation and stress of existing tunnels. This paper proposed an innovative methodology to predict deformation in existing tunnel structures and estimate additional stress during the excavation of a new shield tunnel. The reliability of the suggested calculation method was verified using measured internal force and convergence data of the structures. The results demonstrated that the Long Short-Term Memory (LSTM) model could more effectively establish the temporal correlation between the excavation parameters of new tunnels and the deformation of existing tunnels. Compared to the Recurrent Neural Network (RNN) model, the R2 of the LSTM model increased by 11.81% in the prediction of the tunnel waist and 9.38% in the prediction of the tunnel crown. The Light gradient boosting machine (LightGBM) algorithm was used to analyze the crucial factors of deformation of the existing tunnel structures during shield tunneling, and the results showed that the relative position and the average earth pressure were the essential factors. Furthermore, a calculation method for the additional stress of existing tunnel structures was proposed based on the load structure model. The method assumed that the additional load was distributed rectangularly at the top and bottom of the existing tunnel, and triangularly at the waist of the tunnel. The comparison between the calculated results and the measured results indicated that the phased characteristics of the internal force changes in the existing tunnel structure during the construction of a new tunnel could be accurately reflected by this method.

Dynamic compressive properties and self-similarity characteristics of deep coral reef limestone subjected to high loading rates

Coral reef limestone is a kind of porous anisotropic geo-material. Understanding its dynamic mechanical properties subjected to high loading rates is of great significance to the blasting excavation and military attack defense of the reef underground space. In this paper, the Split Hopkinson Pressure Bar tests were carried out on the specimens of deep coral reef limestone in the South China Sea, and the difference of dynamic response between deep reef limestone and shallow calcified coral skeleton was revealed. The results show that the pore structure affects the dynamic deformation response of coral reef limestone, which makes the strain rate of the specimen independent of other mechanical parameters. However, the high loading rate overcomes the influence of the primary pore structure on the strength, so that the dynamic compressive strength and the degree of breakage are linearly related to the stress rate. In addition, under high loading rate, the coral framework limestone is mainly damaged by tension, which is significantly different from the calcified coral skeleton along the coral growth line. At the same strain rate, the fractal dimension of the dry specimen is greater than that of the saturated one, and the self-similarity characteristics of the specimen fragments that reach the crushing level at higher strain rate are poor. The viscous effect of water hinders the propagation of cracks in the coral framework limestone, but free water reduces the surface energy of the crystal boundary. These two kinds of mechanisms compete with each other, and the key factors controlling the competition mechanism are water content and loading rate.

Mechanical Behavior Monitoring and Load Inversion Analysis of Large-Diameter Underwater Shield Tunnel during Construction.

The construction of large-diameter shield tunnels underwater involves complex variations in water and earth load outside the tunnel segment, as well as intricate mechanical responses. This study analyzes the variation laws of external loads, axial forces, and bending moments acting on the segment ring during the shield assembly and removal from the shield tail. It accomplishes this through the establishment of an on-site monitoring system based on the Internet of Things (IoT) and proposes a Bayesian-genetic algorithm model to estimate the water and earth pressure. The fluctuation section exhibits a peak load twice as high as that in the stable section. These variations are influenced by Jack thrust, shield shell force, and grouting pressure. The peak load observed in the fluctuation section is twice as high as the load observed in the stable section. During the shield tail removal process, the internal forces undergo significant fluctuations due to changes in both load and boundary conditions, and the peak value of the axial force during the fluctuation section is eight times higher than that during the stable section, while the peak value of the bending moment during the fluctuation section is five times higher than that during the stable section. The earth and water pressure calculated using the inversion analysis method, which relies on the measured internal forces, closely matches the actual measured values. The results demonstrate that the accuracy of the water and earth pressure obtained through inversion analysis is twice as high as that obtained using the full coverage pressure method. These results can serve as a valuable reference for similar projects.

Optimization of Double Hole Composite Plate on the Floater Compartment of Amphibious Aircraft Using Taguchi Method

A floater or pontoon is one of the most important components of amphibious aircraft to assist the take-off and landing operation. The inner structure of the floater consists of compartments to carry some payload and to reinforce the structural strength due to water and aerodynamic load that occurred during the aircraft operation. The composite material is chosen instead of metal to reduce the weight of the floater. One of the problems on the composite panel is the existence of some holes due to joint with another part or also to minimize its weight. In this study, the optimization of the composite plate with the existence of a double hole is done using the Taguchi Method. The objective of this optimization is to minimize the stress that happens due to the tensile load. The Finite Element Method is used to calculate the maximum stress and stress distribution on the plate. Tsai-Hill failure criterion is used to make sure that the optimum design does not fail. This optimization considers open hole configuration, the ratio between diameter, and hole distance, as well as the fiber orientation as the control factors. The Taguchi L9 Orthogonal Array is used to make 9 design variations from 3 control factors and 3 levels. This process also considers the thickness of the lamina and material strength as noise factors. The optimization process results in the optimum composite design as follows: 1st double hole configuration (in line with the load direction), the ratio between diameter and hole distance is 0.5, and the fiber direction is [0/90/45/-45]s. The maximum in-plane stress of the optimum design is 39.56 MPa with the Tsai-Hill value is 0.23, so the design does not fail. This optimum configuration of the composite plate can be used to make design considerations for an amphibious aircraft floater compartment.

Anisotropic Deformation in a Polymer Slab Subjected to Fluid Adsorption.

Nanoporous adsorbents can mechanically swell or shrink once upon the accumulation of guest fluid molecules at their internal surfaces or in their cavities. Existing theories in this field attribute such sorption-induced swelling to a tensile force, while shrinkage is always associated with a contractive force. In this study, however, we propose that the sorption-induced deformation of a porous architecture is not solely dictated by the stress conditions but can also be largely influenced by its mechanical anisotropy. In more detail, the sorption-induced deformation of a polymeric slab is investigated using a hybrid molecular dynamics and Monte Carlo algorithm. When subjected to water loading, the slab is found to swell along its normal direction and display an overall positive volumetric strain. Moreover, the surface roughness is enhanced as a response to the surface energy decrease induced by the water covering the slab external surface. Unexpectedly, the in-plane deformation of the slab material seems to be highly constrained, so that it is far below its normal counterpart. This anisotropy is enhanced when the slab thickness decreases. With a thickness of around 1.35 nm, an in-plane shrinkage is observed throughout the entire hygroscopic range. A theoretical analysis based on a poromechanical model suggests that the anisotropic mechanical properties, which are common for a slab material, are the essence of the constrained in-plane swelling or even shrinkage under the isotropic sorption-induced tensile forces. This study, unveiling overlooked mechanisms of sorption-induced shrinkage in mechanically anisotropic materials, provides new insights into this field.

Flexural isostatic response of continental-scale deltas to climatically driven sea level changes

Abstract. The interplay between climate-forced sea level change, erosional and depositional processes, and flexural isostasy in deep time on passive margin deltas remains poorly understood. We performed a series of conceptual simulations to investigate flexural isostatic responses to high-frequency fluctuations in water and sediment load associated with climatically driven sea level changes. We model a large drainage basin that discharges to a continental margin and produces a large deltaic depocenter, then prescribe synthetic and climatic-driven sea level curves of different frequencies to assess flexural response. Results show that flexural isostatic responses are bidirectional over 100–1000 kyr timescales and are in sync with the magnitude, frequency, and direction of sea level fluctuations and that isostatic adjustments play an important role in driving along-strike and cross-shelf river mouth migration and sediment accumulation. Our findings demonstrate that climate-forced sea level changes produce a feedback mechanism that results in self-sustaining creation of accommodation into which sediment is deposited and plays a major role in delta morphology and stratigraphic architecture.

Mechanical Characterization of Dissolving Microneedles: Factors Affecting Physical Strength of Needles.

Dissolving microneedles (MNs) are novel transdermal drug delivery systems that can be painlessly self-administered. This study investigated the effects of experimental conditions on the mechanical characterization of dissolving MNs for quality evaluation. Micromolding was used to fabricate polyvinyl alcohol (PVA)-based dissolving MN patches with eight different cone-shaped geometries. Axial force mechanical characterization test conditions, in terms of compression speed and the number of compression needles per test, significantly affected the needle fracture force of dissolving MNs. Characterization using selected test conditions clearly showed differences in the needle fracture force of dissolving MNs prepared under various conditions. PVA-based MNs were divided into two groups that showed buckling and unbuckling deformation, which occurred at aspect ratios (needle height/base diameter) of 2.8 and 1.8, respectively. The needle fracture force of PVA-based MNs was negatively correlated with an increase in the needle's aspect ratio. Higher residual water or higher loading of lidocaine hydrochloride significantly decreased the needle fracture force. Therefore, setting appropriate methods and parameters for characterizing the mechanical properties of dissolving MNs should contribute to the development and supply of appropriate products.

Oxygen exchange mechanisms in zeolite chabazite under steaming conditions

Under hydrothermal conditions, zeolite frameworks can readily incorporate oxygen from water, via reactive oxygen exchange. This indicates that zeolite frameworks are highly labile and reactive to water, even when stable against full hydrolytic dissolution. However, the routes by which oxygen is exchanged between water and framework have not been established. In this work, we identify the preferable oxygen exchange mechanisms in the zeolite chabazite (CHA) and compare them to hydrolysis and other framework healing mechanisms under the low water concentrations relevant for steaming conditions. We find that oxygen exchange occurs at defect sites that are created by the first hydrolysis step, both in Al–O and Si–O bonds and is competitive with subsequent hydrolysis and non-exchange framework healing processes. Furthermore, we determine the effect of increased water concentration, finding that for both Al–O and Si–O bonds, the second water can either moderately enhance or hinder both hydrolysis and O-exchange, depending on the geometry of the site. This implies that local water concentration is an important factor with varied effects on zeolite stability as a function of water loading. This work provides feasible routes of oxygen exchange in CHA, which together with hydrolytic pathways, govern the stability and mesoporosity of these important porous materials.

Formation of Ethanolamine-Mediated Surfactant-Free Microemulsions Using Hydrophobic Deep Eutectic Solvents.

Hydrophobic deep eutectic solvents (HDESs) are emerging as versatile, relatively benign, and inexpensive alternatives to conventional organic solvents in a diverse set of applications. In this context, the formation of microemulsions with HDES replacing the oil phase has become an area of active exploration. Because of recent reports on the undesirable toxicity of many common surfactants, efforts are under way to investigate the formation of surfactant-free microemulsions (SFMEs) using HDES as an oil phase. We present SFME formation using HDESs constituted of n-decanoic acid and five (5) structurally different terpenoids [thymol, l(-)-menthol, linalool, β-citronellol, and geraniol] at a 1:1 molar ratio as the oil phase and water as the hydrophilic phase. Ethanolamine (ETA) exhibited the best potential as a hydrotrope among several other similar small molecules. Results showed a drastic increase in water solubility within the HDESs in the presence of ETA. ETA exerted its hydrotropic action at different extent for each DES system via chemical interaction with the H-bond donor (HBD) constituent of the HDES. The optimum hydrotropic concentration (minimum hydrotrope and maximum water retention, XETAOPT) assigned for each DES/ETA/water system and water loading are reported, and the trends are discussed in detail. Ternary phase diagrams are constructed using visual observation and the dye staining method. The area under the single- and multiple-phase regions (assigned in ternary phase diagrams) was estimated. "Pre-Ouzo" enforced by ETA was investigated using dynamic light scattering (DLS) of the DES/ETA/water systems at XETAOPT. A systematic growth in nanoaggregates was observed with the subsequent addition of water in DES/ETA systems while continuously changing the existing microstructure. The presence of a core (oil)-shell (water)-like structure as indicated by the fluorescence response of Nile red in the "pre-Ouzo" region is speculated. We were able to prepare a homogeneous solution of [K3Fe(CN)6] salt in "pre-Ouzo" mixtures with no apparent deviation in the Beer-Lambert law.

Enhancement the solar box cooker performance using steel fibers

AbstractThe use of fossil fuel and wood for cooking poses health, environmental, and economic challenges, especially with the growing population. This has led to an increase in the trend towards the use of clean and sustainable cooking sources, including solar cookers. This experimental study aims to contribute by enhancing the performance of a solar box cooker (SBC) according to the concept of porous media via adding steel fibers inside the box as a modified SBC and comparing it with a conventional SBC. The stagnation test to determine the first figure of merit and the load test to determine the second figure of merit, standard boiling time, and cooker optothermal ratio were conducted under the outdoor conditions of Baghdad city. Also, an energy and exergy efficiency analysis, and calculating the rate of heat loss by three water loads heating and cooling tests. The results revealed that the modified SBC has a higher thermal performance than the conventional SBC.

Self-reported musculoskeletal disorder symptoms and associated factors among water carrying women in Legambo district, Northeastern Ethiopia: a community-based cross-sectional study design.

Musculoskeletal disorders are the leading cause of illness, disability, and poor quality of life. Lack of access to potable water in the backyard forces women to take water from off-plot sources every day, which may expose them to various health risks. However, there has been little investigation on the musculoskeletal disorders' health effects on water-carrying women. This study aimed to assess musculoskeletal disorders symptoms and associated factors among water-carrying women in the Legambo district, Northeastern Ethiopia. A community-based cross-sectional study was done with 618 water-carrying women chosen using simple random and systematic random sampling techniques. The data were collected using face-to-face interviews with the standard Nordic Musculoskeletal Questionnaire. Data entry were carried out using Epi-data version 4.6 and exported to SPSS version 25.0 for analysis. A binary logistic regression was used to determine the factors associated with self-reported musculoskeletal disorder symptoms at a 95% confidence interval (CI). In the multivariate model, variables with a p-value ≤0.05 and a 95% CI were declared as factors of self-reported musculoskeletal disorder symptoms. The model's fitness was assessed using Hosmer and Lemeshow, and it was found to be fit. The prevalence of self-reported MSD symptoms was 72.5% during the previous 12 months. MSD symptoms were significantly elevated among women who carried water from a distance of 501-1,000 m [adjusted odds ratio (AOR) = 5.39, 95% CI = 3.64-9.69] and >1,000 m (5.93, 2.84-12.40), carried a water load of >15 kg during pregnancy (8.29, 2.97-23.09), and carried a water load of >15 kg when not pregnant (1.59, 1.44-2.68). Three-fourths of the participants had self-reported musculoskeletal disorder symptoms in the past 12 months. Distance of water sources from their house, carrying the same amount of water during pregnancy, and weight of the water load carrying were factors associated with the self-reported musculoskeletal disorder symptoms. Hence, health professionals should raise awareness of the association between carrying high water loads and the development of MSDs, especially during pregnancy. Improvement in water supply infrastructure and enhancing behavioral intervention should be done. Furthermore, Future researchers should assess MSDs using objective measurements and cohort studies should be implemented.

Testing solar cookers for cooking efficiency

Solar Cookers International (SCI) staff developed and implemented a calculation to measure the cooking efficiency of solar thermal cookers. The calculation complements and enhances SCI's existing performance evaluation process (PEP), which can now be used for determining both the standard cooking power and the cooking efficiency for solar thermal cookers. The standard cooking power value is a single measure of solar cooker performance taken when the temperature of the test water load is specifically 50 °C greater than ambient temperature. Cooking efficiency values extend the perspective of solar cooker performance, as they are applicable to a continuum of load temperature measurements made during a heating cycle. Cooking efficiency is the ratio of energy absorbed by the solar cooking load divided by the input solar energy intercepted by the device during a test interval. Examples of cooking efficiency calculations using water loads during three days of testing for an anonymous group of different types of solar cookers are: solar box oven (18.9 %), reflective-panel solar cooker (28.5 %), parabolic reflector (35.2 %), and evacuated-tube solar cooker (34.6 %).