Applications of the DNA-based material for lasing and dynamic holography

We present results of possible applications of a modified DNA-dye system for lasing and dynamic optical information recording. The system consisted of bio-polymeric matrix made of deoxyribonucleic acid (DNA) substituted with cationic surfactant molecule cetyltrimethyl-ammonium chloride (CTMA) and doped with a photochromic (Disperse Red 1) or fluorescent (Rhodamine 6G) molecules. Results of optical information recording were obtained in a typical degenerate two wave mixing experiment. For sample excitation we used a linearly polarized light of λ = 514.5 nm delivered by an argon ion (Ar+) laser. For amplified spontaneous emission measurements we used 6 ns pulses of 532 nm wavelength delivered by Nd:YAG laser doubled in frequency

Automatic measurement of short-term variability of repolarization to indicate ventricular arrhythmias in a porcine model of cardiac ischaemia

AIMS: An automated method for determination of short-term variability (STV) of repolarization on intracardiac electrograms (STV-ARIauto) has previously been developed for arrhythmic risk monitoring by cardiac implantable devices, and has proved effective in predicting ventricular arrhythmias (VA) and guiding preventive high-rate pacing (HRP) in a canine model. Current study aimed to assess (i) STV-ARIauto in relation to VA occurrence and secondarily (ii-a) to confirm the predictive capacity of STV from the QT interval and (ii-b) explore the effect of HRP on arrhythmic outcomes in a porcine model of acute myocardial infarction (MI). METHODS AND RESULTS: Myocardial infarction was induced in 15 pigs. In 7/15 pigs, STV-QT was assessed at baseline, occlusion, 1 min before VA, and just before VA. Eight of the 15 pigs were additionally monitored with an electrogram catheter in the right ventricle, underwent echocardiography at baseline and reperfusion, and were randomized to paced or control group. Paced group received atrial pacing at 20 beats per min faster than sinus rhythm 1 min after occlusion. Short-term variability increased prior to VA in both STV modalities. The percentage change in STV from baseline to successive timepoints correlated well between STV-QT and STV-ARIauto. High-rate pacing did not improve arrhythmic outcomes and was accompanied by a stronger decrease in ejection fraction. CONCLUSION: STV-ARIauto values increase before VA onset, alike STV-QT in a porcine model of MI, indicating imminent arrhythmias. This highlights the potential of automatic monitoring of arrhythmic risk by cardiac devices through STV-ARIauto and subsequently initiates preventive strategies. Continuous HRP during onset of acute MI did not improve arrhythmic outcomes

Elektrolityczne oczyszczanie sciekow modelowych

Bezpośrednio porównano parametry oraz efekty elektrolitycznego oczyszczania ścieków modelowych w warunkach chronopotencjometrycznych (CHRp), tj. przy stałym natężeniu prądu (I = const) oraz chronoamperometrycznych (CHRa), tj. przy stałym napięciu (U = const). Elektrokoagulację na elektrodach żelaznych, przy zmianie kierunku prądu na elektrodach co 256 s, prowadzono w systemie ciągłej recyrkulacji ścieków pomiędzy zbiornikiem i elektrolizerem. Średnie napięcie, obliczone z kilkunastu tysięcy zarejestrowanych wartości, potrzebne do utrzymania I = const w CHRp zastosowano następnie jako U = const w elektrokoagulacji CHRa wyznaczając z kolei odpowiednie średnie natężenie prądu. Uzyskana w tych warunkach równoważność obu procesów (CHRp i CHRa) umożliwiła bezpośrednie zestawienie rezultatów oczyszczania badanych ścieków, z którego wynika, że elektrokoagulację należy prowadzić w warunkach chronopotencjometrycznych, tzn. przy stałym natężeniu prądu.Parameters and results of electrolytic treatment of the model wastewater under chronopotentiometric (CHRp) conditions, i.e. at constant current (I = const), and under chronoamperometric (CHRa) conditions, i.e. at constant voltage (U = const), were compared in the study. Electrocoagulation was carried out in a system of constant recirculation between the tank and electrolyzer, on iron electrodes where the current direction was changed every 256 s. Mean voltage, calculated on the basis of a few dozen thousand values recorded in the study, and required to maintain I = const during CHRp electrocoagulation, was then applied as U = const during CHRa electrocoagulation, determining mean current intensity. This enabled to ensure equivalence of both processes (CHRp and CHRa) and to compare the results of wastewater treatment, which indicate that electrocoagulation should be performed under chronopotentiometric conditions, i.e. at constant current intensity

Wplyw procesow anoksycznych na emisje siarkowodoru ze sciekow

W miesiącach letnich rejestrowano emisję siarkowodoru oraz wybrane parametry odpływu z oczyszczalni ścieków komunalnych w rejonie atrakcyjnym turystycznie. Porównano wykresy emisji H₂S w pomieszczeniu krat oczyszczalni, przed i po dozowaniu azotanu(V) wapnia oraz PIX-u do rurociągu doprowadzającego ścieki. Określono również wpływ zastosowanych preparatów na jakość odpływu z oczyszczalni. Stwierdzono, że oba badane preparaty, w mniejszym lub większym stopniu, eliminują septyczność ścieków dopływających do oczyszczalni objawiającą się stałą emisją H₂S, przy czym krótkookresowe emisje siarkowodoru towarzyszą zawsze wyładunkowi cystern dowożących ścieki z obszarów nieskanalizowanych. Zasugerowano rozwiązanie problemu bądź przez zmianę miejsca i technologii rozładunku cystern, bądź poprzez kosztowną hermetyzację zbiornika wstępnego z zastosowaniem np. biofiltru.Hydrogen sulfide emission and selected parameters of the effluent from a municipal sewage treatment plant located in a recreation area were recorded in the summer months. The curves of H₂S emission at the screenings-separation room were compared before and after adding calcium nitrate and PIX to the wastewater-supply pipeline. The effects of these chemicals on effluent quality were also determined. It was found that both, calcium nitrate and PIX eliminated, to a higher or lower degree, sewage inflow septicity that manifested itself by constant H₂S emission. However, short-term sulfur hydrogen emissions always accompany the unloading of tank trucks transporting wastewater from unsewered areas. In order to solve this problem, the site and method of truck unloading should be changed. Another alternative is an expensive airtightening of the preliminary treatment tank, using e.g. Biofilters

Non-cardiac chest pain: prognosis and secondary healthcare utilisation

Contains fulltext : 200273.pdf (publisher's version ) (Open Access)Objective: Presentations of non-cardiac chest pain (NCCP) to the emergency department (ED) are increasing. More knowledge of prognosis and healthcare utilisation of patients with NCCP is necessary to optimise their management. Methods: This study is a prospective, observational, prevalence-based cohort study conducted from September 2015 to February 2016 with 1-year follow-up including all patients 18 years and older referred to the ED with chest pain. Discharge diagnoses, mortality, major adverse cardiac events (MACE), re-presentations to the ED, hospitalisations, cardiac interventions and outpatient monitoring were assessed. Results: More than 60% of the 1239 patients presenting with chest pain were discharged with NCCP. The all-cause 1-year mortality rate of patients with NCCP was 2.3% compared with 7.2% in patients with cardiac chest pain (CCP) (p<0.001) and the occurrence of MACE was 5.1% vs 8.3%, respectively (p=0.026). Previous history of coronary artery disease (CAD) in patients with NCCP was identified as a predictive factor for MACE (OR 4.30 (95% CI 1.24 to 14.89), p=0.021). Patients with NCCP had more non-invasive interventions than patients with CCP (proportion of 0.225 vs 0.165 per patient, p<0.001) and 13.7% of patients with NCCP re-presented at the ED within 1 year. Conclusion: The majority of patients referred to the ED with chest pain are discharged with NCCP. The prognosis of patients with NCCP is better than patients with CCP; however, they are at risk for MACE due to a history of CAD. Patients with NCCP moreover use a substantial amount of medical resources, stressing the importance of good triage to minimise unnecessary healthcare utilisation while still preventing MACE

Non-cardiac chest pain : Prognosis and secondary healthcare utilisation

Objective Presentations of non-cardiac chest pain (NCCP) to the emergency department (ED) are increasing. More knowledge of prognosis and healthcare utilisation of patients with NCCP is necessary to optimise their management. Methods This study is a prospective, observational, prevalence-based cohort study conducted from September 2015 to February 2016 with 1-year follow-up including all patients 18 years and older referred to the ED with chest pain. Discharge diagnoses, mortality, major adverse cardiac events (MACE), re-presentations to the ED, hospitalisations, cardiac interventions and outpatient monitoring were assessed. Results More than 60% of the 1239 patients presenting with chest pain were discharged with NCCP. The all-cause 1-year mortality rate of patients with NCCP was 2.3% compared with 7.2% in patients with cardiac chest pain (CCP) (p<0.001) and the occurrence of MACE was 5.1% vs 8.3%, respectively (p=0.026). Previous history of coronary artery disease (CAD) in patients with NCCP was identified as a predictive factor for MACE (OR 4.30 (95% CI 1.24 to 14.89), p=0.021). Patients with NCCP had more non-invasive interventions than patients with CCP (proportion of 0.225 vs 0.165 per patient, p<0.001) and 13.7% of patients with NCCP re-presented at the ED within 1year. Conclusion The majority of patients referred to the ED with chest pain are discharged with NCCP. The prognosis of patients with NCCP is better than patients with CCP; however, they are at risk for MACE due to a history of CAD. Patients with NCCP moreover use a substantial amount of medical resources, stressing the importance of good triage to minimise unnecessary healthcare utilisation while still preventing MACE