The temperature dependence and specificity of transfer of membrane constituents from donor transitional endoplasmic reticulum to the cis Golgi apparatus were investigated using a cell-free system from rat liver. The radiolabelled transitional endoplasmic reticulum donors were prepared from slices of rat liver prelabelled with [14C]leucine. The acceptor Golgi apparatus elements were unlabelled and immobilized on nitrocellulose. When Golgi apparatus stacks were separated by preparative free-flow electrophoresis into subfractions enriched in cisternae derived from the cis, medial and trans portions of the stack respectively, efficient specific transfer was observed only to cis elements. Trans elements were devoid of specific acceptor capacity. Similarly, when transfer was determined as a function of temperature, a transition was observed in transfer activity between 12 degrees C and 18 degrees C similar to that seen in vivo for formation of the so-called 16 degrees C cis Golgi-located membrane compartment. Transfer at temperatures below 16 degrees C and transfer to trans Golgi apparatus compartments at temperatures either above or below 16 degrees C was similar and unspecific. The unspecific transfer at low temperature was pH independent, whereas specific transfer was greatest at the physiological pH of 7, and was reduced to 10% and 18% of that occurring at pH 8 and pH 5.5 respectively. These findings show that the cell-free system derived from rat liver exhibits a high degree of fidelity to transfer in vivo, an efficiency approaching that observed in vivo, and a nearly absolute acceptor specificity for cis Golgi apparatus. The acceptor-, temperature- and pH-specificity of the cell-free transfer, as well as the saturation kinetics exhibited with respect to acceptor Golgi apparatus, support the concept of transition-vesicle-specific docking sites of finite number associated with cis Golgi apparatus cisternae.

The oxidative degradation of aliphatic, aromatic, and secondary polyurethanes was investigated over a range of temperatures of 440–1000°C as a function of time and oxygen concentration. The degradation was studied with special emphasis on HCN‐evolution; its rate constants and Arrhenius equations were determined. In some of the temperature ranges reactions were diffusion controlled. At relatively low temperatures the oxidative rate constant was a linear function of oxygen concentration, whereas at higher temperatures oxidation of the evolved HCN took place in passage through the hot zone of the furnace; in addition, at these higher temperatures thermal degradation of the polymers and thermal decomposition of HCN in the hot zone occurred simultaneously with oxidation to an appreciable extent. The kinetics and mechanism proposed and quantitatively evaluated account well for the experimental results.

SynopsisHCN evolution from thermal and oxidative degradation of poly(dipheny1 methane pyromellitimide) has been investigated over a range of temperatures from 500 to 1000°C; rate constants and Arrhenius emuations have .been determined. Kinetics and mechanisms have been proposed and quantitatively evaluated. They account well for the experimental results. The rate determining steps are C-N scission for thermal degradation and H abstraction from the methylene bridge by 0 2 for oxidative degradation, respectively. At high temperatures, oxidation and thermal decomposition of the evolved HCN take place on its passage through the hot zone of the furnace in the highest range of temperatures (800-1000"C). Additional HCN is produced (>80O0C) from the char obtained during thermal and oxidative degradation. m01.3.5

Objectives: The coronavirus disease 2019 (COVID-19) pandemic globally impacted healthcare due to surges in infected patients and respiratory failure. The pandemic escalated nursing burnout syndrome (NBS) across the workforce, especially in critical care environments, potentially leading to long-term negative impact on nurse retention and patient care. To compare self-reported burnout scores of frontline nurses caring for COVID-19 infected patients with burnout scores captured before the pandemic and in non-COVID-19 units from two prior studies.Methods: The descriptive study was conducted using frontline nurses working in eight critical care units based on exposure to COVID-19 infected patients. Nurses were surveyed in 2019 and in 2020 using Maslach Burnout Inventory (MBI), Well Being Instrument, and Stress-Arousal Adjective Checklist (SACL) instruments.Researchers explored relationships between survey scores and working in COVID-19 units.Results: Nurses working in COVID-19 units experienced more emotional exhaustion (EE) and depersonalization (DP) than nurses working in non-COVID units (p= .0001).Pre-COVID nurse burnout scores across six critical care units (EE mean = 15.41; p= .59) were lower than burnout scores in the COVID-19 intensive care units (EE mean = 10.29; p= .74). Clinical significance (p= .08) was noted by an EE subscale increase from low prepandemic to moderate during the pandemic. Conclusion:Pinpointing associations between COVID-19 infection and nurse burnout may lead to innovative strategies to mitigate burnout in those caring for the most critically ill individuals during future pandemics. Further research is required to establish causal relationships between sociodemographic and work-related psychological predictors of NBS.

SynopsisThe evolution of HCN from the oxidation of nylon 66 has been studied in three apparatuses of different design (all based on stream flow) over a temperature range from 390 to 700°C. Although the numerical values for rate constants (diffusion controlled) and energies of activation differ, the same mechanism is deduced from the results of the three designs. It is concluded that a simple horizontal tube in a furnace is the most efficient apparatus as far as sweeping out volatile products is concerned. The mechanism of thermal oxidative degradation has been evaluated in detail. It is shown that mechanisms where the first reaction step is not the slowest or the slowest one of f i t or second order all fit the experimental results. However, it is concluded that the mechanism where the f i t step is first order and the slowest one is the most likely one. The respective parameters have been evaluated for the results obtained from the horizontal tube apparatus.