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•The recent advances achieved in photoanodes/cathodes for PEC water splitting are reviewed.•Key challenges in the fabrication of highly efficient and stable photoelectrodes are ...explicated.•Deliberations are also given on emerging photoelectrode materials for PEC water splitting.•Strategies and outlooks for the future improvement of solar-driven PEC devices are highlighted.
The development of alternative clean and renewable fuels has become the need of the hour due to the decreasing supply of fossil fuels. Solar hydrogen produced from water is a sustainable, green substitute for fossil fuels for a variety of applications (e.g., transport, power generation, and industrial energy). However, cost-effective, efficient, and stable production of hydrogen fuel from water is a challenge for real-world applications. In pursuit of cost-effective and large-scale commercialization (e.g., photoproduction) of hydrogen from water, attempts were made to describe an up-to-date knowledge on photoelectrochemical (PEC) water splitting processes. In this respect, solar hydrogen production based on semiconductor photoelectrodes (PEs) is regarded as a highly effective option. In this review, we summarize the development of the PEC-based water splitting processes with respect to the efficiency and stability of the PEs. This study is thus expected to help open new paths for the establishment of a sustainable, renewable, and clean energy economy.
This study evaluates the efficacy of the calcaneo-stop (C-Stop) procedure's effectiveness in treating symptomatic flexible flatfoot (FFF) in children.
A systematic review and meta-analysis were ...conducted using PubMed, Embase, and Cochrane databases to identify studies until 2023 on the outcomes of the C-Stop procedure in children with FFF. The risk of bias was assessed using MINORS criteria.
Of 85 studies screened, 20 involving 2394 feet from 1415 patients (mean age 11.2 ± 1.3 years) were included. Post-procedure, significant improvements were noted in pain reduction (93.5%), heel alignment (95.21%), and radiological measures, including reductions in Kite (7.32º), Meary (11.65º), Costa-Bartani angles (17.11º), talar declination (12.63º) and increase in Calcaneal Pitch Angle (5.92º). AOFAS scores increased by 22.32 points on average, with 94.83% reporting high satisfaction. Complication rate was low (7.8%).
The C-Stop procedure is effective for treating FFF in children, offering significant clinical, radiological, and functional improvements with high patient satisfaction and a low complication rate.
Level IV, Systematic review of Level-IV studies
Introduction: Foot is a complex segmented structure formed by the articulation of 26 different bones which are held together by multiple ligaments, extrinsic tendons and the intrinsic muscles of the ...feet. The assessment of median longitudinal arch serves as an important reference in determining the degree of pes planus or pes cavus. This study aims to find the prevalence of pes planus among the undergraduate medical students of a medical college.
Methods: A descriptive cross-sectional study was carried out in the first- and second-year undergraduate medical students of a teaching hospital after taking ethical approval from Institutional Review Committee. The study was conducted from 15th November 2019 to 14th November 2020. Eighty-seven participants were involved in study using the random sampling technique. Foot prints were collected from the participants in the A4 size paper after applying ink over plantar surface of the foot. Measurements were done using the Autodesk Autocad software. Statistical Package for the Social Sciences was used. Point estimate at 95% Confidence Interval was calculated along with frequency and proportion for binary data.
Results: Out of the total subjects, 14 (8.04%) (5.14-10.94 at 95% Confidence Interval) presented with flat foot. Similarly, high arched foot was seen in 29 (16.67%) of subjects whereas normal arched foot was seen in 131 (75.29%) subjects.
Conclusions: From the current study we conclude that the prevalence of pes planus was slightly higher than that compared with the similar studies.
Payment for ecosystem services (PES) is an important policy aiming to promote environmental protection. However, existing studies only focus on the historical PES and ignore their predictions, which ...leads to the mismatch and inefficient use in funds for supporting PES (PES funds). This paper takes the regions of Zhejiang-Jiangsu-Shanghai in China as the study area, and develops a systematic method integrating land-use change, CA-Markov model and ecosystem service value (ESV) model to predict the PES standards and optimizes PES funds allocation from 2025 to 2040. The results show that farmland and forest will be largely transformed into construction land. ESV will increase and its distribution will involve significant spatial differences caused by the increase in wetland, water, and forest, and the equivalent factor. The PES funds obtained by this region are obviously underestimated; Taking ecological gain as the basis for optimizing PES fund allocation, Zhejiang, Jiangsu and Shanghai obtained 274 million USD, 168 million USD and 150 million USD from 2025 to 2040, respectively. This study can provide a reference for governments of developing countries to manage these funds, improve their use efficiency and alleviate regional contradictions.
•A systematic framework for predicting future PES standard is provided.•Land use change is integrated into the research of PES prediction.•The future PES standards in the study area are seriously underestimated.•There is a mismatch between PES funds and ecological gains.
•C-PES/PES UF blend membrane as functionalized membrane.•PEI deposition reaction on blend UF membrane surface to make NF membrane.•Optimal C-PES/PES ratio was needed to obtain NF membrane with ...optimal performance.•High organic and slat rejection obtained with reaction deposition of PEI on functionalized UF membrane.
A positive surface thin-film composite membrane was prepared via evaporation deposition and the reaction of polyethyleneimine (PEI) with the carboxyl groups on the surface of a carboxylated polysulfone (C-PES)/PES UF blend membrane. UF blend membranes with different C-PES/PES ratios were prepared and PEI solution was deposited on them, with subsequent cross-linking using glutaraldehyde. The optimal C-PES/PES ratio was used on the supporting UF blend membrane, with optimal crosslinking time using glutaraldehyde to obtain a significant rejection of salt and organic molecules rejection, while retaining the water flux at a reasonable level. The preparation of a UF blend membrane with a negative surface charge based on the C-PES/PES ratio and its interaction with PEI solutions with different concentrations for deposition and reaction was the key point in obtaining a membrane with the appropriate rejection of divalent cation and organic solutes. The effects of the membrane surface charge on the rejection of different salts and organic solutes were evaluated at different pressures to understand the rejection mechanism of the prepared NF membranes.
In this study is presented the result obtained for the treatment of waste water from the medical sector using membrane filtration system. Polyethersulfone (PES) membranes were obtained using ...Dimethylformamide DMF like solvent, with different concentration to determine the rejection variation of different dyes. Membranes were obtained by the immersion precipitation method and permeation properties were determined by dead end technique. The results show that the membranes filtration method can by improved to reduce the cost of the water treatment from the medical sector. Using DMF solvent membranes with a smaller concentration of polymer have a good rejection results in comparison with other membranes obtained with different solvents.
This paper examines the level of payment for ecosystem services (PES) concept implementation in the financing of water-related forest ecosystem services (ES) in the Republic of Croatia, the ...Federation of Bosnia and Herzegovina (FB&H), the Republic of Slovenia, and the Republic of Serbia. The focus is on water-related forest ES recognised by the millennium ecosystem assessment (MEA). For the purpose of this paper, the term pure PES describes schemes that comply to all five conditions set by Wunder definition and term PES like for those schemes that miss some of those conditions. In the first step, the most important legislative documents related to forests, water, and environmental protection were selected. The second consists of a content analysis; focusing on the definition of ES; the definition of fees or payments; the establishment of ‘forest funds’, ‘water funds’, or ‘environmental funds’; and the way these funds were spent. Here we looked at the flow of funding into the forestry sector recognising forest management as the main water-related forest ES provider. Research revealed existence of well-established payments schemes in forestry in Croatia for almost 30 years and in FB&H for some 20 years which were assessed as closest to pure PES. In Serbia and Slovenia, there were no PES or PES like schemes in the forestry sector. In the water sector the well-established PES like payments schemes existing in all four countries. The environmental protection sector, however, rely more on the tax like rather than on the PES like schemes. Legislation in general recognised the link between forests and water, but this was much more evident in the forestry than in the water or environment sector. The role of the state is strongly pronounced in all countries studied, and was the main driving force behind all payments. However, this position of the state represents also the main obstacle for the development of pure PES schemes, together with underdeveloped private forestry and complex socio-economic conditions. Nevertheless, there is room for further development of pure PES and PES like schemes based on EU or global experiences.
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•PES/SPSf membrane was prepared via NIPS method using adipic acid as additive.•A sponge-like structure was formed due to the H-bonding between adipic acid & SPSf.•Hydration radius was ...estimated by MD simulations to reveal the rejection of dyes.•The membrane exhibited a higher dye rejection at low ionic strength.•High rejection of membrane for dyes was a synergy of size sieving and charge effect.
Polyethersulphone (PES)/sulfonated polysulphone (SPSf) tight ultrafiltration (TUF) membrane was tailored for dye/salt selective separation via non-solvent induced phase separation (NIPS) method using adipic acid (AA) as a pore forming agent. Sucrose and PEG (200–1000 Da) as neutral model molecules and eight kinds of charged dye model molecules (269.3–960.8 Da) were employed to explore the roles of size sieving and charge effect during the membrane separation process. Results showed that the membrane obtained from the casting solution with the mass ratio of PES/SPSf = 84/16 and 11 wt% AA possessed a fully sponge-like structure with an average pore size of 1.8 nm and the molecular weight cut off (MWCO) of 7250 Da. The pure water permeance of the membrane was up to 72.2 L/m2 h bar and displayed a reasonable retention for the neutral molecules including PEG 1000 (46.0%), PEG 400 (19.7%) and sucrose (17.2%). Simultaneously, the membrane exhibited a higher rejection for dyes with the similar molecular weight (Mw) such as methyl orange (MO) (69.4%), acid blue 25 (AB25) (92.6%) and Evans blue (EB) (100%). The high rejection for these dyes was mainly attributed to the synergy between the size sieving and charge effect. Furthermore, the rejection of membrane for methyl red (MR), MO and AB25 was 50.1%, 69.4% and 92.6%, respectively. Molecular dynamics (MD) simulations revealed that the hydration radius of AB25 (1.04 nm) was bigger than that of MR (0.94 nm) and MO (0.99 nm), leading to higher rejection illustrating that size sieving played an important role in the rejection of dyes (Mw less than 696.7 Da) with the same charge. Specifically, the contribution rate of steric hindrance and charge effect to the dye rejection gradually decayed as an increase on the molecular weight of dyes (over 416.0 Da). In addition, the rejection of MR, MO, indigo carmine (IC) and acid fuchsin (AF) decreased with an increase in the ionic strength of feed solutions due to the shielding effect of space charge. In summary, our work provides a profound understanding of the membrane selective separation mechanism for dye wastewater treatment and reuse.
•Isotropic polyethersulfone (PES) membrane was successfully developed via the vapor-induced phase separation (VIPS) method.•The isotropic PES membrane demonstrated outstanding underwater ...superoleophobicity (OCA of crude oil, 145 ± 2.0) and oil-repellency properties.•The isotropic PES membrane has superior water permeability of 4721 L/h⋅m2⋅bar that is about 13.6 times higher than that recorded by anisotropic PES.•The isotropic PES membrane showed excellent oil-in-water emulsion separation efficiency (>98%) for different heavy oil concentrations.•The isotropic PES membrane showed durable oil-fouling repellency, which could be easily recycled with a flux a recovery ratio of 59.5% over three subsequent cycles.
Isotropic polyethersulfone (PES) membrane for separation of oil-in-water nanoemulsion was successfully developed using non-solvent vapor-induced phase separation (VIPS). The surface and structural properties of the fabricated PES membranes were thoroughly characterized using various techniques. The membrane separation performance was evaluated in terms of permeate flux, oil rejection, antifouling capability, and water flux recovery. Remarkably improved surface hydrophilicity for isotropic PES membrane (contact angle, CA = 39°) compared to anisotropic PES membrane (CA = 70°), resulting in superior pure water permeance, attaining 4721 L/h⋅m2⋅bar at operating pressure of 0.5 bar. The isotropic PES membrane achieved superior crude oil-in-water nanoemulsion separation (permeance of 713 L/h⋅m2⋅bar and 100% rejection) at oil concentration of 1 g/L. At extremely high oil concentration of 50 g/L, the PES membrane was not completely fouled and showed permeance of 65 L/h⋅m2⋅bar and 98.2% rejection. Moreover, the flux recovery of the fouled isotropic PES membrane exceeded 59.5% over three subsequent cycles of filtration and back-washing with water. Overall, this study might provide substantial guidance for large-scale manufacturing and application of isotropic PES membrane in treating practically challenging emulsified oil-in-water nanoemulsion under harsh conditions.
Biologically treated palm oil mill effluent (POME) still has a dark-brown color and contains residual organic matter. In this paper, a novel self-cleaning mixed matrix K-B-N triple doped-TiO2/PES ...nanofiltration membrane at three weight fractions (0.1, 0.5 and 1 wt%) was prepared by the phase inversion method. The performance of the prepared membranes was investigated in terms of permeability, fouling resistance and capability for post treatment of the biologically treated POME. The prepared membranes were characterized by contact angle measurement, scanning electron microscopy (SEM) and atomic force microscopy (AFM). The obtained results indicated that the pure water flux of the modified membranes improved significantly by addition of K-B-N-TiO2 nanoparticles up to 0.5 wt% which could be attributed to the hydrophilic nature of the nanoparticles and induced photocatalytic ability. Also, flux recovery ratio (FRR) of the optimized membrane was increased from 48 to 95.4% relative to unfilled membrane that confirmed antifouling and self-cleaning capability of the nanocomposite. This behavior was ascribed to the photocatalytic role of the nanoparticles resulting mineralization of organic matter from surface of the modified membrane that enhanced reusability of the prepared membranes. Maximum permeation flux, dye and COD removal efficiencies were obtained about 27 kg/m2 h, 98% and 90%, respectively for treating the biologically treated POME.
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