This review summarizes the recent development and studies of anaerobic membrane bioreactor (AnMBR) to control fouling issues. AnMBR is an emerging waste water treatment technology mainly because of ...its low sludge residual, high volumetric organic removal rate, complete liquid-solid separation, better effluent quality, efficient resource recovery and the small footprint. This paper surveys the fundamental aspects of AnMBRs, including its applications, membrane configurations, and recent progress for enhanced reactor performance. Furthermore, the membrane fouling, a major restriction in the practical application of AnMBR, its mechanism and antifouling strategies like membrane cleaning, quorum quenching, ultrasonic treatment, membrane modifications, and antifouling agents are briefly discussed. Based on the review, the key issues that require urgent attention to facilitate large scale and integrated application of AnMBR technology are identified and future research perspectives relating to the prevalent issues are proposed.
•Recent advancements in anaerobic membrane bioreactors (AnMBR) are concisely reviewed.•The fouling mechanism and the advanced antifouling strategies are summarized.•Costs incurred in different operational steps of AnMBR are compared.•Future research is needed for techno-economic analysis of large scale applications.
An investigation into the effect of stepwise saline introduction (3–20 g·L−1 NaCl) on the anaerobic ammonium oxidation (anammox) process in a lab-scale sequencing batch reactor was carried out for ...252 days by evaluating the changes in influent and effluent nitrogen concentrations, conductivity, microbial extracellular polymeric substances' (EPS) ionic content, as well as stresses due to salinity, via microbial ATP analysis. It was observed that, effluent nitrogen concentrations remained stable at low saline levels of 3 g·L−1 to 10 g·L−1. Nonetheless, midway through 10 g·L−1 and the preliminary phase of 15 g·L−1 salinity presented a very unstable, highly fluctuating as well as deteriorating effluent nitrogen concentrations. A more satisfactory nitrogen removal efficiency of 83.7 ± 5.9% was obtained at higher saline concentrations implying that, the adaptation mechanism to tolerate increasing salinity was taking place. Saline induced stress, which measures the variation in viable anammox bacteria, was correlative to the formation of EPS and changes in its cationic contents along the increasing salinity. Although the specific anammox activity (SAA) dropped by approximately 15% from the beginning of the process to the midpoint, the drop in SAA after the midpoint was not as drastic as the initial phase. A change in microbial aggregation and dominance proved the existence of new saline-dependent species that can withstand high saline stresses. Recovery from abrupt high saline shocks in batch experiment was seen to be almost impossible.
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•Saline induced stress correlates uniquely to the saline adaptation of anammox.•Improvement in N-removal efficiency is observed at higher saline concentrations.•Granules formation and bacteria aggregation tailored the saline input profile.•MAB dominated the granules in the reactor by the latter end of 10 g·L−1 salinity.
Rhizobacteria contain various plant-beneficial traits and their inoculation can sustainably increase crop yield and productivity. The present study describes the growth-promoting potential of ...Brevundimonas spp. isolated from rhizospheric soil of potato from Sahiwal, Pakistan. Four different putative strains TN37, TN39, TN40, and TN44 were isolated by enrichment on nitrogen-free malate medium and identified as Brevundimonas spp. based on their morphology, 16S rRNA gene sequence, and phylogenetic analyses. All strains contained nifH gene except TN39 and exhibited nitrogen fixation potential through acetylene reduction assay (ARA) except TN40. Among all, the Brevundimonas sp. TN37 showed maximum ARA and phosphate solubilization potential but none of them exhibited the ability to produce indole acetic acid. Root colonization studies using transmission electron microscopy and confocal laser scanning microscopy showed that Brevundimonas sp. TN37 was resident over the root surface of potato; forming sheets in the grooves in the rhizoplane. TN37, being the best among all was further evaluated in pot experiment using potato cultivar Kuroda in sterilized sand. Results showed that Brevundimonas sp. TN37 increased growth parameters and nitrogen uptake as compared to non-inoculated controls. Based on the results obtained in this study, it can be suggested that Brevundimonas spp. (especially TN37) possess the potential to improve potato growth and stimulate nitrogen uptake. This study is the first report of Brevundimonas spp. as an effective PGPR in potato.
Scaling, or inorganic fouling, is a major factor limiting the performance of membrane-based water treatment processes in long-term operation. Over the past few decades, extensive studies have been ...conducted to control the scale growth found in membrane processes and to develop sustainable and greener processes. This study details the role of CO2 in scale inhibition in membrane processes. The core concept of CO2 utilization is to reduce the influent pH and to minimize the risk of scale formation from magnesium or calcium salts. Three reverse osmosis (RO) units were operated with a control (U1), CO2 (U2), and a commercial antiscalant, MDC-220 (U3). The performances of all the units were compared in terms of change in transmembrane pressure (TMP). The overall efficiency trend was found as U1 > U3 > U2. The membrane surfaces were analyzed using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) for the morphological and elemental compositions, respectively. The surface analysis signified a significant increase in surface smoothness after scale deposition. The noticeable reduction in surface roughness can be described as a result of ionic deposition in the valley region. A sludge-like scale layer was found on the surface of the control membrane (U1) which could not be removed, even after an hour of chemical cleaning. After 20–30 min of cleaning, the U2 membrane was successfully restored to its original state. In brief, this study highlights the sustainable membrane process developed via CO2 utilization for scale inhibition, and the appropriate cleaning approaches.
Stroke is the fourth leading cause of mortality and is estimated to be one of the major reasons for long-lasting disability worldwide. There are limited studies that describe the application of ...physical therapy interventions to prevent disabilities in stroke survivors and promote recovery after a stroke. In this review, we have described a wide range of interventions based on impairments, activity limitations, and goals in recovery during different stages of a stroke. This article mainly focuses on stroke rehabilitation tactics, including those for sensory function impairments, motor learning programs, hemianopia and unilateral neglect, flexibility and joint integrity, strength training, hypertonicity, postural control, and gait training. We conclude that, aside from medicine, stroke rehabilitation must address specific functional limitations to allow for group activities and superior use of a hemiparetic extremity. Medical doctors are often surprised by the variety of physiotherapeutic techniques available; they are unfamiliar with the approaches of researchers such as Bobath, Coulter, and Brunnstrom, among others, as well as the scientific reasoning behind these techniques.
CO2 capture and utilization (CCU) is a promising approach in controlling the global discharge of greenhouse gases (GHG). This study details the experimental investigation of CO2 utilization in ...membrane-based water treatment systems for lowering the potential of ionic precipitation on membrane surface and subsequent scale development. The CO2 utilization in feed water reduces the water pH that enables the dissociation of salts in their respective ions, which leave the system as a concentrate. This study compares the efficiency of CO2 and other antifouling agents (CA-1, CA-2, and CA-3) for fouling control in four different membrane-based wastewater reclamation operations. These systems include Schemes 1, 2, 3, and 4, which were operated with CA-1, CA-2, CA-3, and CO2 as antiscalants, respectively. The flux profile and percent salt rejection achieved in Scheme 4 confirmed the higher efficiency of CO2 utilization compared with other antifouling agents. This proficient role of CO2 in fouling inhibition is further endorsed by the surface analysis of used membranes. The SEM, EDS, and XRD examination confirmed the higher suitability of CO2 utilization in controlling scale deposition compared with other antiscalants. The cost estimation also supported the CO2 utilization for environmental friendly and safe operation.
Spasticity is a common issue among children, especially those with bilateral spastic cerebral palsy (CP). Selective dorsal rhizotomy (SDR) is a surgical procedure that is often used to decrease lower ...limb rigidity, alongside other treatment options such as intrathecal medication, peripheral nerve surgery, and deep brain stimulation (DBS). The objective of these therapies is to improve the standard of living for young individuals. This article intends to explain the motor deficits observed in spastic diplegia and a rehabilitation program using physical therapy after SDR. The information can help with counseling parents about the prognosis and developing a clinical treatment plan. The article presents a case study of a 12-year-old girl who recently underwent L3, L4, and L5 nerve root rhizotomy in the physical therapy department. It highlights the importance of long-term physical therapy follow-up and orthotic usage in the management of spastic diplegia.
PurposeThe purpose of this systematic review is to summarize the possible organizational outcomes related to knowledge management capabilities (KMCs). It aims at offering the modern-day dynamic ...organizations a path, through which they can utilize KMC at hand for gaining competitive advantage and positive organizational outcomes. The review is based on previous studies in the field of knowledge management and explains how KMCs are associated with various organizational outcomes.Design/methodology/approachA systematic approach was utilized to collect, examine, interpret and synthesize researches regarding KMCs and their usefulness for various organizational outcomes. The meta-synthesis method was adopted to review 106 research papers after careful selection.FindingsIt was evident from this integrated review that KMCs help in promoting organizational effectiveness, innovative ability, organizational change, value creation, competitive advantage, organizational learning and performance. Furthermore, the current review suggests research avenues and knowledge gaps in current literature to provide future researchers unique research opportunities.Originality/valueThe review revealed a profound opinion that organizations have to develop an optimal mix of KMCs to achieve better organizational outcomes. The study identified how KMCs set a basis and build positive support to enhance the key organizational outcomes such as organizational effectiveness, innovative ability, organizational change, value creation, competitive advantage, organizational learning and performance. However, cooperation bias is one of the most considerable limitations in research studies included in this systematic literature review.
Exopolysaccharide (EPS) show remarkable properties in various food applications. In this review paper, EPS composition, structural characterization, biosynthesis pathways, and recent advancements in ...the context of application of EPS-producing Lactobacillus spp. in different food industries are discussed. Various chemical and physical properties of Lactobacillus EPS, such as the structural, rheological, and shelf-life enhancement of different food products, are mentioned. Moreover, EPSs play a characteristic role in starter culture techniques, yogurt production, immunomodulation, and potential prebiotics. It has been seen that the wastes of fermented and non-fermented products are used as biological food for EPS extraction. The main capabilities of probiotics are the use of EPS for technological properties such as texture and flavor enhancement, juiciness, and water holding capacities of specific food products. For these reasons, EPSs are used in functional and fermented food products to enhance the healthy activity of the human digestive system as well as for the benefit of the food industry to lower product damage and increase consumer demand. Additionally, some pseudocereals such as amaranth and quinoa that produce EPS also play an important role in improving the organoleptic properties of food-grade products. In conclusion, more attention should be given to sustainable extraction techniques of LAB EPS to enhance structural and functional use in the developmental process of food products to meet consumer preferences.
This study explores the nexus of industrialization, economic growth, and carbon dioxides (CO2) emission for Chinese economy along with trade openness and population density. It also evaluates the ...environmental Kuznets curve (EKC). The computed estimates reveal that population density, industry, and trade increase the Chinese CO2 emission, while per capita GDP deteriorates CO2 emissions in the long-run. It also found a bidirectional causal link between CO2 emission and industrialization and a uni-directional relationship between population density and trade openness structure, respectively. Variance decomposition impulse analysis spotlights the time-lag of CO2 emission, industrialization, and per capita GDP, respectively which are major predictors of Chinese CO2 emission. The present study likely to open debate about the literature since the course concludes with a discussion on the short-run and long-run implications for China while providing policy suggestions for the policymakers.
•U-shaped or inverted U-shaped EKC hypothesis tested using ARDL method in the long and short-run for China.•Fill the gap between income, industrialization, population density and trade openness in the literature.•The impact of population density, Industry, trade, and income on CO2 emissions is significant both positively and negatively.•In decomposition variance impulses, population density is positive, and other variables are negative.