14 research outputs found

    The Kinetics of Aquation of Amminepentaaquachromium(III) Ion. A Comparison with Unsaturated Amine Ligands

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    The aquation of amminepentaaquachromtwn(III) ion was studied as a function of acidity and temperature at ~t = 1.0 M (HCl04 + NaCl04). The rate law is of the form - dln [Cr(H20)s (NH3) 3+]/dt = k0 + k_1/[W]. The entha1py (kcal mol-1) and entropy (cal mo1-1 K-1) of activation for the acid-independent path are 27.8 and - 5.3, and for the acid-inverse path 34.8 and 7.0. The corresponding specific rates extrapolated to 25 °c are 1.8 x 10-9 s-1 and 7.0 X 10-12 M s-1• Cr(H20)5(NH3) 3+ aquates significantly faster than expected on the basis of the linear correlation between - log k 0 and pKa of the free ligands established for the analogous complexes with a series of substituted pyridine ligands. Implications of this observation are discussed

    Morbidity and mortality after anaesthesia in early life: results of the European prospective multicentre observational study, neonate and children audit of anaesthesia practice in Europe (NECTARINE)

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    BACKGROUND: Neonates and infants requiring anaesthesia are at risk of physiological instability and complications, but triggers for peri-anaesthetic interventions and associations with subsequent outcome are unknown. METHODS: This prospective, observational study recruited patients up to 60 weeks' postmenstrual age undergoing anaesthesia for surgical or diagnostic procedures from 165 centres in 31 European countries between March 2016 and January 2017. The primary aim was to identify thresholds of pre-determined physiological variables that triggered a medical intervention. The secondary aims were to evaluate morbidities, mortality at 30 and 90 days, or both, and associations with critical events. RESULTS: Infants (n=5609) born at mean (standard deviation [sd]) 36.2 (4.4) weeks postmenstrual age (35.7% preterm) underwent 6542 procedures within 63 (48) days of birth. Critical event(s) requiring intervention occurred in 35.2% of cases, mainly hypotension (>30% decrease in blood pressure) or reduced oxygenation (SpO2 <85%). Postmenstrual age influenced the incidence and thresholds for intervention. Risk of critical events was increased by prior neonatal medical conditions, congenital anomalies, or both (relative risk [RR]=1.16; 95% confidence interval [CI], 1.04–1.28) and in those requiring preoperative intensive support (RR=1.27; 95% CI, 1.15–1.41). Additional complications occurred in 16.3% of patients by 30 days, and overall 90-day mortality was 3.2% (95% CI, 2.7–3.7%). Co-occurrence of intraoperative hypotension, hypoxaemia, and anaemia was associated with increased risk of morbidity (RR=3.56; 95% CI, 1.64–7.71) and mortality (RR=19.80; 95% CI, 5.87–66.7). CONCLUSIONS: Variability in physiological thresholds that triggered an intervention, and the impact of poor tissue oxygenation on patient's outcome, highlight the need for more standardised perioperative management guidelines for neonates and infants

    Difficult tracheal intubation in neonates and infants. NEonate and Children audiT of Anaesthesia pRactice IN Europe (NECTARINE): a prospective European multicentre observational study

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    BACKGROUND: Neonates and infants are susceptible to hypoxaemia in the perioperative period. The aim of this study was to analyse interventions related to anaesthesia tracheal intubations in this European cohort and identify their clinical consequences. METHODS: We performed a secondary analysis of tracheal intubations of the European multicentre observational trial (NEonate and Children audiT of Anaesthesia pRactice IN Europe [NECTARINE]) in neonates and small infants with difficult tracheal intubation. The primary endpoint was the incidence of difficult intubation and the related complications. The secondary endpoints were the risk factors for severe hypoxaemia attributed to difficult airway management, and 30 and 90 day outcomes. RESULTS: Tracheal intubation was planned in 4683 procedures. Difficult tracheal intubation, defined as two failed attempts of direct laryngoscopy, occurred in 266 children (271 procedures) with an incidence (95% confidence interval [CI]) of 5.8% (95% CI, 5.1–6.5). Bradycardia occurred in 8% of the cases with difficult intubation, whereas a significant decrease in oxygen saturation (SpO2<90% for 60 s) was reported in 40%. No associated risk factors could be identified among co-morbidities, surgical, or anaesthesia management. Using propensity scoring to adjust for confounders, difficult anaesthesia tracheal intubation did not lead to an increase in 30 and 90 day morbidity or mortality. CONCLUSIONS: The results of the present study demonstrate a high incidence of difficult tracheal intubation in children less than 60 weeks post-conceptual age commonly resulting in severe hypoxaemia. Reassuringly, the morbidity and mortality at 30 and 90 days was not increased by the occurrence of a difficult intubation event

    Hydrogen Peroxide in the Troposphere

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    Uloga vodikova peroksida (H2O2) u atmosferskoj kemiji i njegov doprinos u nastanku slobodnih radikala počeli su se proučavati tek posljednjih nekoliko desetljeća. Fotokemijskim reakcijama s ozonom i H2O2 nastaju oksidansi (slobodni radikali) koji mogu oksidirati biomolekule unutar stanica te dovesti do smrti stanica i ozljeda tkiva. Zbog toga se slobodni radikali smatraju uzrokom više od sto bolesti. H2O2 smatra se boljim indikatorom za atmosferski oksidacijski kapacitet od ozona. U atmosferi može biti prisutan u plinovitoj i tekućoj fazi te pokazuje tipične dnevne i sezonske varijacije. Me|utim, zbog skupe i slo`ene opreme, mjerenja H2O2 su rijetka i ograničena na samo nekoliko mjesta u svijetu. Mjerenja u slojevima leda na Grenlandu pokazala su da koncentracije H2O2 rastu posljednjih 200 godina. Značajan porast primijećen je upravo posljednjih dvaju desetljeća, a procjene pokazuju da će i dalje rasti zbog smanjene emisije sumporova dioksida. Mjerenja H2O2 u Hrvatskoj do sada još nisu bila provedena te će uporedo s već postojećim dugogodišnjim rezultatima mjerenja ozona i dušikovih oksida dati uvid u stanje i utjecaj na oksidativni stres.The past few decades saw a rising interest in the role of hydrogen peroxide (H2O2) in atmospheric chemistry and its contribution to the formation of free radicals. Free radicals (oxidants) are formed by photochemical reactions between ozone and H2O2. Free radicals formed within cells can oxidise biomolecules, and this may lead to cell death and tissue injury. For this reason, free radicals are believed to cause more than 100 diseases. H2O2 has been suggested as a better indicator of atmospheric oxidation capacity than ozone. Atmospheric H2O2 can appear in the gas phase or in the aqueous phase. It shows typical diurnal and seasonal variations. However, measurements of H2O2 with expensive and sophisticated equipment are rare and limited to but a few sites in the world. Measurements in Greenland ice cores showed that H2O2 concentrations increased over the last 200 years and most of the increase has occurred over the last 20 years. Evaluations show that concentrations will still rise as a result of decreasing SO2 emission. H2O2 measurements have not been carried out in Croatia until now, and, accompanied by the existing longterm measurements of ozone and nitrogen oxides, they will provide an idea of the oxidative capacity of the atmosphere and its influence on oxidative stress

    Croatia

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    This paper investigates the legal framework for collective bargaining in the Re-public of Croatia. The first part of the paper gives an overview of the legal sources for collective bargaining and collective agreements together with a deep analysis of the role of collective agreements in the labour law system in Croatia. The second part focuses on the trade union density in Croatia and the process of social dialogue and collective bargaining. Then the paper deals with the national collective bargaining model and globalization of the economy, with special attention of the state of facts in the period of the economic crisis. In the final part the authors give their final thoughts with some de lege ferenda suggestions
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