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Mixed matrix membranes (MMMs) were formed by using seven polymeric matrices with a wide range of permeabilities. All of the polymeric matrices have been polyimides, namely: P84, Pi-DAPOH, Pi-DAROH, Matrimid, Pi-HABAc, PI-DAM, and PIM-1 in the order of increasing O 2 permeability. A fixed (10%) concentration of a microporous organic polymer (TFAP-Trp), formed by the combination of trifluoroacetophenone and triptycene, was added as a porous filler. The material properties as well as their separation performances for multiple pure gases, specifically the permeabilities of He, N 2 , O 2 , CH 4 , and CO 2 , were measured. The correlation between the relative increase in permeability in MMMs and that of the matrix polymeric membrane has been quantitatively analyzed. This study proves that the increased permeability of MMMs is largely linked to the contribution of the high permeability of the filler. The addition of the TFAP-Trp porous filler proves to be especially beneficial for matrices with low to moderate permeabilities, significantly enhancing the matrix permeability overall. The fitted relationship is approximately linear in accordance with the existing models to predict permeability in dual-phase systems for low proportions of the dispersed phase. An extrapolation allows the evaluation of the permeability of the pure microporous organic polymer, which agrees with the previous values described by the group for different filler contents and in other polymeric matrices. In all cases, the selectivity remains approximately constant while the permeability increases. The addition of TFAP-Trp to all the polymeric matrices led to a moderate improvement of the MMM separation performances, mainly centered on their permeabilities., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Objective: To evaluate agreement between risk-assessment models for venous thromboembolism (VTE) in patients hospitalized for medical conditions and to analyze variables associated with the decision to prescribe pharmacological thromboprophylaxis in hospital emergency departments (EDs). Conclusions., Methods: Prospective observational multicenter cohort study. We included adults attended in 15 hospital EDs who were hospitalized for medical conditions, calculating VTE risk according to the International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) score, the Padua Prediction Score (PPS), and the National Institute for Health and Care Excellence (NICE) score. In addition to assessing interscore concordance, we analyzed variables associated with the prescription of thromboprophylaxis in the ED., Results: A total of 1203 patients were included. The PADUA, IMPROVE, and NICE scales assigned high risk scores for 68.7%, 47.4%, and 69.5% of the patients, respectively. The κ statistic for agreement between the PADUA and NICE scores was 0.80 (95% CI, 0.76-0.84); 102 patients (8.5%) had discordant scores. The κ statistics for agreement between the IMPROVE score and the PADUA and NICE classifications were 0.47 (95% CI, 0.43-0.52) and 0.37 (95% CI, 0.33-0.42), respectively; 322 (26.8%) and 384 patients (31.9%), respectively, had discordant scores. Variables associated with starting thromboprophylaxis in the ED were a diagnosis of acute myocardial infarction or stroke (adjusted odds ratio [aOR], 4.26), immobility in the last 2 months (aOR, 2.19), chronic obstructive pulmonary disease (aOR, 1.97), ischemic heart disease (aOR, 1.51), reduced mobility of 3 days or longer (aOR, 1.14), body mass index (aOR, 1.04), age (aOR, 1.02), recent trauma or surgery (aOR, 0.40), and risk for bleeding (aOR, 0.56)., Conclusions: There is disagreement among the recommended models for predicting risk for VTE in patients hospitalized for medical conditions. The basis for emergency physicians' clinical judgment regarding thromboprophylaxis extends beyond risk scales to include multiple risk factors for VTE and bleeding.

Objective: To estimate the prevalence of inappropriate use of prophylaxis to prevent venous thromboembolism (VTE) in patients with medical diseases admitted to hospital from the emergency department. To explore variables associated with inappropriate thromboprophylaxis., Methods: Prospective multicenter cohort study in 15 hospital emergency departments. We included patients admitted for a medical condition during 7 days in the first quarter of 2022. We assessed risk for VTE with the Padua Prediction Score (PPS). Inappropriate thromboprophylaxis was defined by failure to prescribe prophylaxis in patients with a high-risk PPS assessment unless there were absolute contraindications (active bleeding or severe thrombopenia) or, alternatively, the prescription of prophylaxis in patients with a low-risk PPS assessment or absolute contraindications. A logistic regression model was adjusted for risk level to identify variables associated with inappropriate use of thromboprophylaxis., Results: Of a total of 630 patients included, 450 (71.4%) had PPS scores indicating high risk for VTE; 180 patients were at low risk. Thromboprophylaxis was inappropriate in 248 patients (39.4%): 165 high-risk patients who received no prophylaxis, 82 low-risk patients who were nonetheless treated, and 1 patient who was treated in spite of severe thrombopenia. Odds ratios (ORs) revealed that the variables associated with inappropriate use of thromboprophylaxis were trauma or recent surgery (OR, 5.53; 95% CI, 1.58-19.34), presence of factors indicating risk for bleeding (OR, 2.61; 95% CI, 1.44-4.73), and hospital admission for either urinary tract infection (OR, 2.29; 95% CI, 1.07-4.87) or gastrointestinal disease (OR, 4.30; 95% CI, 1.71-10.85)., Conclusions: The inappropriate use of thromboprophylaxis in Spanish emergency departments is high and associated with certain clinical characteristics.

Objectives: To describe the management of superficial vein thrombosis (SVT) of the lower limbs in patients treated in Spanish hospital emergency departments (EDs). To evaluate the impact of ED management of venous thromboembolic complications on outcomes and to determine the characteristics of patients who develop complications., Material and Methods: The retrospective multicenter ALTAMIRA study (Spanish acronym for risk factors, complications, and assessment of Spanish ED management of SVT) used recorded data for consecutive patients with a diagnosis of isolated SVT treated in 18 EDs. We gathered data on symptomatic venous thromboembolic disease (deep vein thrombosis, pulmonary embolism, or the extension or recurrence of SVT), clinically significant bleeding, and 180-day mortality. Cox regression analysis was used to explore variables associated with complications., Results: A total of 703 patients were included. Anticoagulation was prescribed for 84.1% of the patients for a median of 30 days (interquartile range, 15-42 days); 81.3% were treated with low molecular weight heparin. A prophylactic dose was prescribed for 48% and an intermediate therapeutic dose for 52%. Sixty-four patients (9.2%) developed symptomatic thromboembolic disease within 180 days, 12 (1.7%) experienced clinically significant bleeding, and 4 (0.6%) died. Complications developed later in patients receiving anticoagulant therapy than in those not taking an anticoagulant (66 vs 11 days , P=.009), and 76.6% of those developing complications were not on anticoagulant when symptoms appeared. A history of thromboembolic disease was associated with developing complications (adjusted hazard ratio, 2.20; 95% confidence interval, 1.34-3.62)., Conclusion: ED treatment of SVT varies and is often suboptimal. The incidence of thromboembolic complications after SVT is high. Starting anticoagulation in the ED delays the development of complications. Patients with a history of thromboembolic disease are more at risk of complications.

Objectives: To describe the characteristics of patients with isolated lower-limb superficial vein thrombosis (SVT) treated in hospital emergency departments and to evaluate adherence to clinical practice guidelines on diagnosis (vein ultrasound imaging) and therapeutic management (start of anticoagulant therapy)., Material and Methods: Retrospective cohort study in 18 Spanish emergency departments. We included all patients with a final emergency department diagnosis of lower-limb SVT aged 18 years or older between January 2016 and May 2017. Backward stepwise multiple logistic regression analysis was used to evaluate adherence to clinical practice guidelines on ordering vein ultrasound imaging and starting anticoagulant therapy., Results: A total of 1166 patients were included. The mean patient age was 59.6 years, and 67.9% were women. About a quarter of the patients (24.4%) had a history of venous thromboembolic disease. Complications developed in 8.9% within 180 days: 4.6% experienced a recurrence and 3.6% progressed to SVT and 1.8% to deep vein thrombosis; pulmonary thromboembolism occurred in 0.9%. Hemorrhagic complications developed in 17 patients (1.5%). Sixteen patients (1.4%) died. Vein ultrasound imagine was ordered for 703 patients (60.3%). Anticoagulant agents were prescribed for 898 (77%) for a median period of 22 days. Variables associated with a decision to order anticoagulants were a history of venous thromboembolic disease (odds ratio [OR], 1.60; 95% CI, 1.12-2.30), varicose veins (OR, 1.40; 95% CI, 1.12-2.30); limb pain (OR, 1.44; 95% CI, 1.08-1.91); painful cord (OR, 1.30; 95% CI, 0.97-1.73); and availability of vein ultrasound images (OR, 1.60; 95% CI, 1.94-3.45)., Conclusion: Adherence to clinical practice guidelines for the diagnosis and treatment of isolated lower-limb SVT is low in Spanish emergency departments. Ultrasound imaging is not ordered for 1 out of every 2 to 3 patients, and anticoagulant treatment is not started in 1 out of 4 patients. There is great room for improvement.

A new generation of porous polymer networks has been obtained in quantitative yield by reacting two rigid trifunctional aromatic monomers (1,3,5-triphenylbenzene and triptycene) with two ketones having electron-withdrawing groups (trifluoroacetophenone and isatin) in superacidic media. The resulting amorphous networks are microporous materials, with moderate Brunauer-Emmett-Teller surface areas (from 580 to 790 m 2 g -1 ), and have high thermal stability. In particular, isatin yields networks with a very high narrow microporosity contribution, 82% for triptycene and 64% for 1,3,5-triphenylbenzene. The existence of favorable interactions between lactams and CO 2 molecules has been stated. The materials show excellent CO 2 uptakes (up to 207 mg g -1 at 0 °C/1 bar) and can be regenerated by vacuum, without heating. Under postcombustion conditions, their CO 2 /N 2 selectivities are comparable to those of other organic porous networks. Because of the easily scalable synthetic method and their favorable characteristics, these materials are very promising as industrial adsorbents.

In this paper we describe a variable stepsize integration method for the Hamiltonian dynamics of point vortices based on the explicit symplectic Zhang and Qin scheme. The adapted method is also explicit and preserves the reversible structure of the flow. In order to check the behavior of this adaptive method a numerical study of the exchange-scattering phenomenon in the three-vortex problem is made. The symmetry of the orbit and the energy evolution are discussed for the exchange-scattering model. A long-term integration of this and other models composed also of three vortices indicates that the adaptive Zhang-Qin method has good properties of efficiency and preservation of the first integrals associated with point vortex systems.

The accumulation of Cd(II), Cu(II), Pb(II) and Zn(II) at mg L(-1) concentration levels by inactive freeze-dried biomass of Pseudomonas Putida has been investigated. These metals could be efficiently removed from diluted aqueous solutions. A contact time of 10 min was sufficient to reach equilibrium. The pH has a strong effect on metal biosorption and the optimal pH values were 6.0, 5.0-6.0, 6.0-6.5 and 7.0-7.5 for Cd(II), Cu(II), Pb(II) and Zn(II) respectively. Under these conditions there was 80% removal for all metals studied. The process of biosorption can be described by a Langmuir-type adsorption model. This model accounts for 98% of the data variance. The K(A) and q(max) parameters for each metal are strongly correlated (at confidence levels greater than 98%) with the metal acidity, quantified by the constant of the corresponding M(OH)(+) complex, thus confirming previous assertions by other authors.

Pineal melatonin secretion exhibits a rhythm which is identified as a circadian cycle with a period of between 20 and 28 h in most animals. The melatonin rhythm has an acrophase of about -30 degrees. The aim of this study was determine the effect of lithium on the melatonin rhythm since lithium is usually used as a therapeutic agent in manic-depressive disease. Lithium induced a delay of the melatonin acrophase which reached a value of about -45 degrees; lithium also produced another peak which had an acrophase at about +60 degrees. We speculate that lithium influences either inositol phosphate turnover or it merely changes the profile of the melatonin rhythm.