Walterzhou8554
In line with experiments, the reactivity of isocyanates toward nucleobases decreases in the order cytosine > adenine > guanine, and we rationalize this order of reactivity by the fall of their basicity and destabilization of the imine forms. Activation barriers of the alternative concerted pathways are higher than that of the preferred stepwise mechanism, and the match to experiment is poor. The kinetic effect of adding electron-withdrawing or electron-donating groups to the aryl group of aryl isocyanate is minute, which suggests that mutagenicity of isocyanates is determined exclusively by the reactivity of the -N═C═O group and as such cannot be removed by structural alterations of the adjacent aryl.China's coal-fired power industry urgently needs deep decarbonization to meet the challenge of climate change. Regional air quality improvement and the health benefits can motivate efforts to achieve low-carbon goals. However, the health cobenefit per amount of carbon reduction may vary drastically across power plant units. The strategy of targeting more health cobenefits has been considered in designing an efficient carbon mitigation pathway, whereas this issue has not been analyzed at the unit level. In this study, an indicator called health benefit by carbon reduction (H/C) was constructed for each power unit to assess the relative potential of obtaining health cobenefits. The results reveal that the distribution of H/C values among units is extremely uneven the first 1, 5, and 20% of the total carbon emission contributed to nearly 20, 40, and 70%, respectively, of the total health effects. The additional health benefits from H/C optimization were evaluated, and the decommissioning pathway of China's coal-fired power industry for achieving more health benefits was explored.Polycyclic aromatic hydrocarbons (PAHs) are routinely screened for in soils, where quantitation of structural isomers is critical due to varying toxicity within PAH isomer classes. While chromatographic methods provide isomer resolution, such strategies are cost and time intensive. To address these challenges, we present condensed phase membrane introduction mass spectrometry using liquid electron ionization/chemical ionization (CP-MIMS-LEI/CI) as a direct mass spectrometry technique that provides rapid, quantitative results for PAH isomer measurements in soil samples. read more A methanol acceptor phase is flowed through a probe-mounted polydimethylsiloxane hollow fiber membrane directly immersed into a dichloromethane/soil slurry. PAHs and dichloromethane co-permeate the membrane into the acceptor solvent, whereas particulates and charged matrix components remain in the sample. A nanoflow of the membrane permeate is then directly infused into a LEI/CI interfaced triple quadrupole mass spectrometer. Diagnostic PAH adduct ions were formed at either M + 45 ([M + CH2Cl + CH3OH-HCl]+) or M + 47 ([M + CHCl2-HCl]+). This allowed the development of specific MS/MS transitions for individual PAH isomers. These transitions were subsequently used for the direct analyses of PAHs in real soils where CP-MIMS-LEI/CI was shown to be rapid (15 soil samples/h) and sensitive (ng/g level detection limits). CP-MIMS-LEI/CI results compared well to those obtained using GC-MS (average percent difference of -9% across 9 PAHs in 8 soil samples), presenting a compelling argument for direct, quantitative screening of PAHs in soils by CP-MIMS-LEI/CI, particularly given the simple workflow and short analytical duty cycle.The phenomenon of local sleep, a concept that has come into somnology relatively recently, has been attracting more and more attention of researchers. Under this name, two groups of phenomena are considered. The first is the appearance in different parts of the cerebral cortex of different EEG patterns during general sleep. The second is the disconnection of certain cortical areas from the processing of extero- or proprioceptive signals and their transition to spiking and slow wave electrical activity, which is typical for sleep, while awake. The authors believe that it is the second phenomenon that can be called real local sleep. The appearance of local cortical sleep is inseparably linked with the occurrence of local wakefulness. It can be expected that the occurrence of local sleep will have detrimental consequences for behavior in urgent and complicated situations, while local wakefulness can adversely affect the visceral health of the body. A possible way of early detection of the local sleep development is proposed. In conclusion, some methodological problems on the way of electrophysiological studies of the local aspects of sleep and wakefulness are considered.Sleep disordered breathing is a frequent comorbidity (50-75%) in patients with chronic heart failure, but it is usually underestimated. This review analyzes sleep disordered breathing in patients with chronic heart failure, demonstrates pathogenetic relationships and the prognostic role of sleep apnea. The authors present modern treatment options for sleep apnea in this cohort (from non-invasive ventilation to implantable devices), highlight the role of drug therapy and outline perspectives of different treatment approaches. This clinical problem is designated as multidisciplinary, which requires a dialogue between researchers and doctors of various specialties to organize comprehensive effective care for this cohort of patients.
To evaluate the features of structural organization of sleep in men 35-55 years of age with varying degrees of severity and duration of clinical manifestations of obstructive sleep apnea syndrome (OSAS) from the perspective of modern pathophysiology.
The study included 49 male patients, aged 35-55 years (average age was 43.4±9.2 years), with a body mass index (BMI) of 33.64±1.2 kg/m
with complaints of snoring of varying degrees of intensity, daytime sleepiness, arrest of breathing during sleep (according to others). The control group consisted of 15 healthy men who did not have complaints of sleep disorders and clinical manifestations of OSAS. The Pittsburgh sleep quality index (PSQI) questionnaire and polysomnographic monitoring study (PSG) were used. According to the results of the polysomnographic study, all patients were divided into 2 subgroups 12 men of group 1with moderate OSAS (duration of clinical manifestations 4.5±1.0 years) and 37 men of group 2 with severe OSAS (duration 1.5±1.5 years).
A decrease in the sleep quality was detected in 61.