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A global outlook of the desalination industry and state-of-the-art technologies for brine valorisation
Full text linkDesalination is increasingly recognized not only as a solution to water scarcity but also as a potential source of valuable resources through brine valorisation. This review presents a comprehensive assessment of the global desalination landscape, focusing on the feasibility of resource recovery within circular economy frameworks. Using the DesalData database, the study maps the distribution and capacity of desalination plants, revealing the dominance of seawater reverse osmosis (SWRO) and the substantial volume of brine produced globally. A quantitative analysis shows that SWRO brine could meet or exceed current production levels for several commodities. Over 30 technologies are evaluated across membrane-based, thermal, and electrochemical categories, with varying maturity and salinity tolerance. While some, such as thermal brine concentrators and crystallizers, are commercially deployed, others like bipolar membrane electrodialysis (BMED), membrane distillation crystallization (MDC), and forward osmosis (FO) remain at pilot or laboratory scale. The review highlights the potential to recover freshwater, salts, critical raw materials, chemicals, and energy, in brine valorisation and identifies more specifically the key challenges to recover such resources of the analyzed technologies including energy consumption, material durability, and economic viability. Industrial case studies demonstrate that large-scale brine mining currently focuses on water and NaCl recovery, while multi-resource recovery remains limited to pilot-scale implementations. Overall, brine valorisation emerges as a promising strategy to transform desalination from a waste-generating process into a circular and resource-efficient solution, though further technological development and scale-up are essential to realize its full potential
Robust Correlated Equilibrium:Definition and computation
No full textWe study N-player finite games with costs perturbed due to time-varying disturbances in the underlying system and to that end, we propose the concept of Robust Correlated Equilibrium that generalizes the definition of Correlated Equilibrium. Conditions under which the Robust Correlated Equilibrium exists are specified, and a decentralized algorithm for learning strategies that are optimal in the sense of Robust Correlated Equilibrium is proposed. The primary contribution of the paper is the convergence analysis of the algorithm and to that end, we propose a modification of the celebrated Blackwell's Approachability theorem to games with costs that are not just time-average, as in the original Blackwell's Approachability Theorem, but also include the time-average of previous algorithm iterates. The designed algorithm is applied to a practical water distribution network with pumps being the controllers and their costs being perturbed by uncertain consumption due to the consumers. Simulation results show that each controller achieves no regret, and empirical distributions converge to the Robust Correlated Equilibrium.</p
Detailed assessment of dynamic startup, shutdown, and flexibility of the adiabatic, gas-and water-cooled methanol fixed bed reactor: Comparison for power to methanol application
No full textIntegration of intermittent renewable energy with methanol synthesis requires that the reactor and separation system be flexible and tolerant to frequent stop–start operation. In this paper, the dynamic load flexibility, start-up, and shutdown characteristics of the water-cooled, gas-cooled, and adiabatic fixed bed reactor are investigated under hot and cold start modes. Parameters such as the flow rates, compositions, reactor temperature evolution with start-up and shutdown, start-up and shutdown time, and the heat transfer characteristics of the reactor are assessed. Different standby and heat management strategies are discussed. It is shown that the load flexibility range of 20–110 % is attainable in the adiabatic and water-cooled reactor systems applied for mildly exothermic methanol synthesis. The gas-cooled reactor system can tolerate a load range of 40–110 %. The gas-cooled reactor has a shorter start-up (21 min) and shutdown time (6 min) followed by the water-cooled and thereafter adiabatic reactor when nitrogen is used for hot standby management. Using H2 during hot standby shortens the start-up time of the reactors up to 15, 30, and 36 min for the gas-cooled, water-cooled, and adiabatic reactors, respectively. While to reduce cost and alleviate safety concerns during long-duration cold standby, the use of N2 is recommended. Cold start-up can take several hours and depends on thermal transients of the catalysts and reactors. Reactors can tolerate fast ramp rates up to 2.22 %/min for load change range (up and down to 20–110 %), up to 2.7–16.67 %/min for start-up, and 0.067–16.67 %/h for shutdown. Fast ramp rates reduce the CO2 emissions during the start-up. Reactors can operate safely with no load/ramp-induced wrong-way behavior and violation of path constraints
Recent advances in yeast and bacteria co-cultivation for bioprocess applications
No full textYeast and bacteria co-cultures can be found in nature and have multiple advantages that can be exploited, nowadays also in a controlled bioproduction environment. Various types of co-cultivation have been used for food applications such as production of flavor compounds in dairy products and alcoholic beverages. Co-cultures can broaden the substrate spectrum for microbial food and feed production, they can increase productivity and efficiency, and the nutritional value. Workflows have been developed from plate to bioreactor scale to increase reproducibility and optimize benefits of individual co-cultivation strategies. Nonetheless, certain limitations need to be overcome for industrial application. Many interactions of microbes, in particular in suspension cultures, are not sufficiently understood or even explored. While more possibilities arose from on-line monitoring of individual populations or even single cells, off-line measurement techniques are still typically applied in order to assess growth and product formation. Promising advances have been achieved, however, by methods for single-cell at-line and on-line analysis in co-cultures which are accounted for to emphasize the current opportunities and challenges in monitoring and controlling co-cultures. This review aims to summarize the recent advances with a particular focus on cultivation procedures and process analysis in bacteria, yeast and bacteria-yeast co-cultures. The implementation of suitable monitoring methods to enable (remote) control and contribute to quality assurance will accelerate the development and optimization of industrial co-culture bioprocesses. This will support transferability and process standardization across world regions adding to the advancement of bioproduction. The applicability of some relevant technology is, however, in its infancy.</p
A clinical guide for physiotherapists to assess and manage cervical musculoskeletal impairment and pain sensitivity in migraine patients
No full textINTRODUCTION: Migraine is a complex neurological disorder characterized by different signs and symptoms, often presenting with an altered pain sensitivity and cervical musculoskeletal impairments. Thus, the management of migraine patients should include the assessment and eventually a specific treatment of these characteristics.PURPOSE: Physiotherapists play a key role in identifying and managing cervical musculoskeletal impairments and altered pain sensitivity in migraine patients. This manuscript provides evidence-based guidance on assessment techniques and clinical reasoning strategies to help physiotherapists effectively evaluate and interpret these characteristics in clinical practice.IMPLICATION: This manuscript serves as a practical guide for physiotherapists by: Outlining physiotherapy assessment techniques for migraine patients.Providing reference cutoff values to identify increased pain sensitivity and cervical dysfunctions.Supporting individualized clinical reasoning to understand these characteristics within each patient's overall condition.Clarifying the rationale behind physiotherapy interventions and integrating hands-on and hands-off therapeutic approaches based on patient-specific needs.</p
Psychometric Properties of the Knee Osteoarthritis Pain Index
No full textOBJECTIVES: The current study sought to evaluate the psychometric properties of a newly developed Knee OsteoArthritis Pain Index (KOAPI), derived from the Brief Pain Inventory (BPI), among individuals with knee osteoarthritis (KOA).METHODS: This study consisted of secondary data analysis of two clinical trials. In study 1, 241 individuals with KOA were evaluated before total knee arthroplasty and six months post-surgery. In study 2, 37 individuals with KOA participated in a randomized, double-blind, placebo controlled, two-way crossover study in which they received either a COX-2 inhibitor followed by a placebo or a placebo followed by a COX-2 inhibitor. The KOAPI was derived from the BPI and included three BPI pain severity items (worst, average, current) and the BPI pain interference item related to pain when walking.RESULTS: The KOAPI showed excellent model fit (CFI = 0.99; TFI: 0.98-0.99; RMSEA: 0.08-0.001), good reliability (Cronbach's alpha: 0.84-0.87) and high convergent validity with the Western Ontario and McMaster Universities Osteoarthritis Index (r = 0.66; 95% CI: 0.44, 0.81) and the Pain Catastrophizing Scale (r = 0.50; 95% CI: 0.39, 0.60).CONCLUSIONS: Overall, the psychometric properties of the KOAPI were comparable or better than those produced by the original BPI pain severity subscale. The KOAPI may be a helpful screening and outcome measure for individuals with KOA that more closely captures symptoms which drive patients to seek clinical care.</p
Outpatient versus inpatient surgery for ankle fractures:A randomized controlled non-inferiority trial
No full textBACKGROUND: Growing evidence supports a shift from inpatient to outpatient surgical treatment for ankle fractures. The primary aim of this study was to investigate the effect of inpatient versus outpatient surgery of ankle fractures on patient-reported outcome utilizing the Foot and Ankle Outcome Score (FAOS) at 12 weeks following surgery. Secondary aims were to report patients' satisfaction, adverse events, pain, physical function, and bone healing between inpatient and outpatient treatment.PATIENTS AND METHODS: The study design was a non-inferiority randomized controlled, non-blinded trial with a two-groups. Patients were randomized 1:1 to outpatient or inpatient surgical treatment. The primary outcome was the FAOS at 12 weeks. Secondary outcomes included patients' satisfaction, health-related quality of life, intensity of pain, bone union, and adverse events.RESULTS: A total of 44 patients were randomized to inpatient surgery and 42 patients to outpatient surgery. The final follow-up at 12 weeks following surgery was completed by 69 patients (80 %). The mean age of patients was 49.2 (SD 16.9), ranging from 18 to 80. Female sex represented 44 % of patients. The primary analysis revealed no statistically significant difference in FAOS subscale scores between inpatient and outpatient surgery at the 12-week follow-up Adjusted mean difference: Pain: -0.8 (95 % CI -10.7-9.0); Symptoms: 2.7 (95 % CI -6.9-12.5); ADL: -4.7 (95 % CI -13.6-4.3); Sport/Rec: 2.9 (95 % CI -15.2-9.3); and QOL: -0.7 (95 % CI -11.8-10.3). Comparable results were observed for secondary outcomes.CONCLUSION: This study showed no statistical nor clinically significant difference in FAOS subscale scores between inpatient and outpatient surgery for ankle fractures 12 weeks following surgery. Furthermore, patients' satisfaction and adverse events were comparable between inpatient and outpatient surgery 12 weeks following treatment. Results indicated that outpatient surgery for ankle fractures is highly feasible for selected patients and may be considered as routine for clinical practice.</p
Centralized vs. Decentralized Monitors for Hyperproperties
Full text linkThis article focuses on the runtime verification of hyperproperties expressed in Hyper-recHML, an expressive yet simple logic for describing properties of sets of traces. To this end, we consider a simple language of monitors that observe sets of system executions and report verdicts w.r.t. a given Hyper-recHML formula. We first employ a unique omniscient monitor that centrally observes all system traces. Since centralized monitors are not ideal for distributed settings, we also provide a language for decentralized monitors, where each trace has a dedicated monitor; these monitors yield a unique verdict by communicating their observations to one another. For both the centralized and the decentralized settings, we provide a synthesis procedure that, given a formula, yields a monitor that is correct (i.e., sound and violation complete). A key step in proving the correctness of the synthesis for decentralized monitors is a result showing that, for each formula, the synthesized centralized monitor and its corresponding decentralized one are weakly bisimilar for a suitable notion of weak bisimulation.</p
Negative outcomes occur early among geriatric patients with early signs of dysphagia in an acute care setting
No full textObjectives: This study aimed to investigate the clinical outcomes associated with early signs of dysphagia (SD) in geriatric patients in an acute care setting. Methods: In this prospective observational study with 18 mo follow-up, geriatric patients were screened for early signs of dysphagia in an acute care setting. Included patients were grouped based on swallowing function—SD or normal swallowing (NS). Follow-up data were retrieved from medical records on 332 patients with complete screening from baseline to 18 mo after admission. Results: Among participants, 52.0% were male, median age was 79 (25th percentile 73.0; 75th percentile 85.0) y and median BMI was 26.1 (22.4;29.8) kg/m 2. Patients with early SD had higher mortality (41.3%) compared with NS (23.3%) (P < 0.001). Both mortality and readmissions occurred within the first 90 d after screening compared with after 90 d. Using multiple hazard regression analyses, risk factors for mortality were identified as increasing age, SD, nutritional risk, low performance status, increasing number of comorbidities, and inflammation markers (P < 0.05). Furthermore, low performance status, a high number of comorbidities, and low hemoglobin were risk factors for readmissions within the 18 mo follow-up period (P < 0.05). Conclusions: Early SD were associated with mortality after 18 mo, but readmissions were mostly pronounced within 90 d. Early dysphagia screening in older patients in general is relevant in the acute care setting as part of nursing care activities.</p