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Impact of liquid viscosity on simplex spray drying atomizer performance
No full textSpray drying, a process which is widely used in the food industry, involves the atomizations of a liquid slurry into a drying chamber to produce a powder of desired properties. Although liquid viscosity strongly influences process efficiency, few studies have examined its effect on spray characteristics for specific system designs, where previous work has been hindered by experimental/numerical challenges or focus on non-food systems. Therefore, this study experimentally quantifies the influence of liquid viscosity and atomizer geometry on the discharge coefficient, global Sauter mean diameter (SMD), and spray cone angle for multiple Delavan SDX V spray drying atomizer geometries under industrially relevant conditions. Performing measurements using water/glycerol mixtures enabled the use of advanced optical diagnostic techniques on mixtures with viscosities within the food-industry-relevant range (1–35 mPa s). Overall, we see that increasing viscosity, raises discharge rate and SMDs while reduces spray cone angle, regardless of pressure or atomizer geometry. We then perform a dimensional analysis over a large measured dataset in order to derive empirical equations linking design parameters to resulting sprays characteristics. We show that these equations are able to reliably predict (R2 > 0.97) the discharge coeficient, SMD and cone angle solely from liquid properties, operating conditions, and nozzle geometry. Alongside an extensive set of measurements, the derived correlations significantly expand predictive capabilities in the medium-to-low viscosity regimes relevant to spray drying in the food industry. These results can be directly applied in process simulations and design workflows, enhancing the precision and efficiency of industrial spray drying optimization
Depth of Anaesthesia Measured by Patient State Index (PSi) Does Not Correlate With Increased Seizure Duration During Electroconvulsive Therapy
No full textBACKGROUND: Seizure duration during electroconvulsive therapy (ECT) correlates with treatment efficacy and may be influenced by depth of anaesthesia. The Patient State Index (PSi), derived from processed EEG, offers a potential method to monitor depth of anaesthesia during ECT. This study examined the correlation between pre-ictal PSi and EEG-seizure duration.METHODS: In this prospective observational study, adult patients undergoing routine ECT at a Swedish university hospital were monitored using the SedLine pEEG system. Anaesthetic care followed standard protocols and the clinical team was blinded to PSi values. Pre-ictal PSi was defined as the final value prior to the ECT stimulus. EEG-seizure duration and relevant clinical variables were extracted from health records. The primary outcome was the association between pre-ictal PSi and EEG-seizure duration, analysed using a linear mixed-effects model adjusting for age and use of benzodiazepines or anticonvulsants. Secondary analyses explored sex and age effects on PSi over time and differences between baseline and pre-ictal PSi.RESULTS: Eighty-seven ECT sessions in 37 patients were analysed. Median baseline PSi was 94 (IQR 4) and pre-ictal PSi was 38 (IQR 31; p < 0.001). No correlation was found between pre-ictal PSi and EEG-seizure duration. There were no significant effects of age or sex on pre-ictal PSi while there was a significant difference between sexes on baseline PSi. Artefact and EMG activity in the EEG signal were minimal.CONCLUSION: Pre-ictal PSi was not associated with EEG-seizure duration.EDITORIAL COMMENT: This study found no evidence to support a correlation between pre-ictal Patient State index and seizure duration, thereby challenging any clinical utility for guiding ECT administration
Analysis of high flux membranes for desalination in waste-heat driven vacuum membrane distillation plants : Experimental validation and techno-economic analysis
No full textVacuum membrane distillation is a promising technology for seawater desalination, as it enables high recovery ratios, with reasonable thermal and minimal electric consumption. Ceramic membranes can offer notable advantages over polymeric membranes, mainly due to their robust thermal and mechanical stability, yet they have limited representation in the literature. Accordingly, this work investigates ceramic membranes and their techno-economic performance for large scale desalination plants, with target recovery ratios above 85 %. First, a one-dimensional model for multilayered membranes was developed in MATLAB, validated against experimental data of water fluxes with different membrane materials, including ceramic ones, specifically collected within this work. This also enabled the fitting of the membrane characteristic parameters with the collected experimental data. With the aim of reducing the thermal consumption, a full-scale plant layout was defined with various stages in cascade and a sensible waste heat source at 90 °C. Results demonstrate that thermal consumption level in the 180–250 kWh/m3 range is possible, with average water fluxes around 20 kg/(m2·h). With reasonable assumptions on capital costs and plant availability, the levelized cost of water was found to be between 3 and $8/m3
Comorbidities and mortality in subgroups of adults with diabetes with up to 14 years follow-up : a prospective cohort study in Sweden
No full textBackground: Subgroups of adult-onset diabetes, namely severe autoimmune diabetes (SAID), severe insulin-deficient diabetes (SIDD), severe insulin-resistant diabetes (SIRD), and mild obesity-related diabetes (MOD) or mild age-related (MARD) diabetes, have been defined with clinical variables and a machine-learning approach. Our aim was to describe their long-term outcomes and mortality. Methods: In this prospective cohort study in Sweden, we used data from two subsets of the All New Diabetics in Scania (ANDIS) project cohort of individuals diagnosed with diabetes at regional care centres and enrolled within 1 year of diagnosis. Included participants were 18 years or older, did not have pancreatitis, and had complete data for cluster variables. We used GAD antibodies, Homeostasis Model Assessment 2 β cell and insulin resistance indices, BMI, HbA1c, and age at the diagnosis of diabetes to group individuals, and logistic and Fine–Gray proportional hazards regression to study prevalent and incident comorbidities, using the MARD group as comparator. Findings: Between Jan 1, 2008, and Nov 3, 2016, for ANDIS1 and Nov 4, 2016, and April 6, 2022, for ANDIS2, a total of 25 590 were screened for eligibility, resulting in 19 076 participants being included in the analysis (9057 from ANDIS1 and 10 019 from ANDIS2; 11 171 men and 7905 women). The median follow-up time was 9·63 years (IQR 4·05) in ANDIS1 and 2·83 years (2·76) in ANDIS2. The SAID and SIDD subgroups had the highest HbA1c values at diagnosis and over time, and the highest age-adjusted and sex-adjusted risk of retinopathy (SAID adjusted hazard ratio [HR] 1·35 [95% CI 1·08–1·70]; SIDD 2·11 [1·82–2·44]) and neuropathy (2·58 [1·87–3·56]; 2·13 [1·69–2·70]). At the diagnosis of diabetes, SIRD had the highest prevalence of hypertension (2336 [69·8%] of 3348) and dyslipidaemia (1484 [44·4%]), and kidney (366 [10·9%]), cardiovascular (1026 [30·6%]), and steatotic liver disease (38 [1·1%]). Despite large differences in HbA1c, both SIDD and SIRD had an increased risk of incident kidney disease, including kidney failure (SIDD adjusted HR 2·94 [1·69–5·09]; SIRD 3·41 [2·06–5·64]), and myocardial infarction (1·44 [1·13–1·82]; 1·51 [1·22–1·87]). SIRD and MOD had the highest risk of atrial fibrillation (adjusted HR 1·32 [1·13–1·54]; 1·58 [1·26–1·98]). The risk of stroke was only increased in SIDD (adjusted HR 1·32 [1·07–1·62]), and steatotic liver disease (3·29 [2·32–4·66]) and heart failure (1·55 [1·34–1·79]) in SIRD. SIDD, SIRD, and MOD had the highest risk of total mortality (adjusted HRs 1·44–1·52) even after adjustment for established risk factors (age, sex, BMI, hypertension, LDL, and smoking), largely driven by cardiovascular mortality. Interpretation: Diabetes subgroups could inform on outcomes, as well as guide treatment and follow-up needed for newly diagnosed individuals with diabetes. SIRD stands out as a high-risk subgroup that is not identified by conventional glycaemia-based risk factors, but bears risk of early onset end-organ damage and would benefit from identification and treatment before the diagnosis of diabetes. Funding: Swedish Research Council, Avtal om Läkarutbildning och Forskning Swedish government grants, Diabetes Wellness Sweden, the Swedish Heart and Lung Foundation, the Crafoord Foundation, the Swedish Diabetes Foundation, the Novo Nordisk Foundation, the Bo and Kerstin Hjelt Foundation, the Albert Påhlsson Research Foundation, Vinnova, and AstraZeneca
Theoretical kinetic study of the reactions between pyridyl radicals and O2
No full textReactions of the primary pyridine radicals, ortho-, meta-, and para-pyridyls with oxygen control the overall rate of pyridine oxidation. In the present work, the potential energy surfaces of o-, m-, and p-pyridyls + O2 previously developed by the authors have been employed for a systematic theoretical kinetic study of the rate constants of these reactions. The geometries of reactants, products, intermediates, and transition states of the reactions of pyridyl radicals with O2 were optimized at the level of density functional theory using the ωB97XD functional with the 6-311G** basis set. The temperature- and pressure-dependent rate constants of 31 reactions were evaluated within the framework of the Rice-Ramsperger-Kassel-Marcus (RRKM) theory combined with the Master Equation approach (RRKM–ME) in the temperature range from 300 to 3000 K, covering pressures from 0.01 to 100 atm. For several reactions previously investigated in the literature, good agreement was demonstrated, indicating consistency and correctness of the present theoretical calculations. Moreover, thermodynamic data for all important reactants, products, and intermediates have been revisited and calculated at the G4 theoretical level. The calculated rate constants and thermodynamic data provide a backbone for the development of detailed kinetic models for pyridine combustion
Pattern recovery by SLOPE
No full textSLOPE is a popular method for dimensionality reduction in high-dimensional regression. Its estimated coefficients can be zero, yielding sparsity, or equal in absolute value, yielding clustering. As a result, SLOPE can eliminate irrelevant predictors and identify groups of predictors that have the same influence on the response. The concept of the SLOPE pattern allows us to formalize and study its sparsity and clustering properties. In particular, the SLOPE pattern of a coefficient vector captures the signs of its components (positive, negative, or zero), the clusters (groups of coefficients with the same absolute value), and the ranking of those clusters. This is the first paper to thoroughly investigate the consistency of the SLOPE pattern. We establish necessary and sufficient conditions for SLOPE pattern recovery, which in turn enable the derivation of an irrepresentability condition for SLOPE given a fixed design matrix X. These results lay the groundwork for a comprehensive asymptotic analysis of SLOPE pattern consistency
Cultural Landscape and Territorio : A Dialogical Analysis of Climate Change Geographies.
No full textThis article puts into dialogue the concept of cultural landscape originating in Anglophone human geography with the notion of territorio coming from Latin American critical human geography. Through a case study of mangrove restoration in the Colombian Caribbean, we examine how climate change politics and policies affect unequal contexts, reshaping environmental, social, and spatial relations. We argue for the need to analyze current climate change geographies and underscore the necessity of a conceptual dialogue between different academic traditions to address these complexities. By bringing together cultural landscape and territorio, we show that climate change is a historical and spatial process influenced by power dynamics, different actors, and historical contexts. By integrating both concepts, the article uncovers the mechanisms behind still-contested geographies. This dialogue aims to contribute to and enrich ongoing debates in human geography and political ecology by incorporating diverse perspectives, demonstrating how these concepts illuminate the material forms of culture, labor, and power relations, thereby providing a nuanced view of human–environment interactions amid climate change
Next generation multi-element monolithic Germanium detectors for spectroscopy : First integration at ESRF facility
No full textThe XAFS-DET work package of the European LEAPS-INNOV project is developing high-purity Germanium detectors for synchrotron applications requiring spectroscopic-grade response. The detectors integrate three key features: (1) newly designed monolithic Germanium sensors optimized to mitigate charge-sharing events, (2) an improved cooling and mechanical design structure supported by thermal simulations, and (3) complete electronic chain featuring a low-noise CMOS technology based preamplifier, enabling high X-ray count rate capability over a broad energy range (5–100 keV). This paper discusses the first integration and characterization of one of the two multi-element Ge detectors at the European Synchrotron Radiation Facility (ESRF). The integration phase included validating high-throughput front-end electronics, integrating them with the Ge sensor, and operating them at liquid nitrogen temperature, in addition to the experimental characterization, which consists of electronics noise study and spectroscopic performance evaluation
Estimating Aggregate Relationships in Panel Data via the LASSO
No full textThis article is concerned with the estimation of aggregate relationships among a potentially large number of panel data variables in the presence of unobserved heterogeneity in the form of interactive effects, an empirically very relevant scenario that has not been considered before. One of our findings is that if the regressors load on the same set of latent factors as the dependent variable, which seems a priori likely since many variables are co-moving, the aggregation automatically accounts for the unobserved heterogeneity. In order to also account for the many regressors, the aggregate model is estimated using a version of LASSO. It is shown that under suitable regulatory conditions, the estimator is oracle efficient and selection consistent, properties that are verified in small samples using Monte Carlo simulations. The empirical usefulness of the estimator is illustrated using as an example the gravity equation of trade
