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981.
982.
This paper presents the research results of the effect of using calcium oxide and potassium permanganate on the combustion of pellets from wheat bran and beet pulp. The measurements were performed in the technical laboratory of the Centre of Energy Utilization of Non-Traditional Energy Sources in Ostrava. The research examined the effect of the use of chemical substances on the amount of air pollutants from biomass thermal conversion in a low-power boiler and the process temperature. First, we performed technical and elementary analyses of agricultural waste. The raw material was then comminuted, mixed with a selected additive, pelletized, and finally burned in a low-power boiler. The additive was added in three proportions: 1:20, 1:10, and 1:6.67 (i.e., 15%) relative to the fuel weight. The combustion process efficiency was measured using a flue gas analyzer and three thermocouples attached to the data recorder. From the measurement results, we were able to determine the percentage reduction of pollutant emissions into the atmosphere (CO, NOx, and SO2) due to the use of additives. Because emission standards are becoming increasingly stringent and fuel and energy prices are rising, the results presented in this article may be useful to agri-food processing plants that want to manage these materials thermally.  相似文献   
983.
Cortical evoked potentials (EP) were investigated in a group of female smokers in separate smoking and non-smoking sessions. In a constant-fore-period S1-S2 reaction time paradigm, EPs were averaged separately to auditory warning (S1) stimuli and visual imperative (S2) stimuli under 4 conditions: (a) a single-choice S1-S2 sequence with no auditory distraction task; (b) a single-choice S1-S2 sequence with concomitant auditory distraction task; (c) a four-choice S1-S2 sequence with no auditory distraction task; (d) a four-choice S1-S2 sequence with concomitant auditory distraction task. Two individual EP peaks, N1 and P2 and one peak-to-peak measure, N1-P2, were involved in amplitude analysis of S1 and S2 stimuli. Tobacco significantly improved the decision time (DT) component of reaction time and increased N1 amplitudes to S1 stimuli. Tobacco also interacted with task complexity to reduce P2 amplitudes to S1. No significant tobacco effects were observed with EPs to S2. The results are discussed in relation to improved attention and information processing.  相似文献   
984.
C Knott  F Reynolds 《Placenta》1986,7(4):333-338
The fetal-to-maternal ratios of carbamazepine, antipyrine and phenytoin are principally determined by maternal protein binding, though greater lipid solubility may enhance the transfer of valproate compared to that of other drugs at high flows. Placental clearance of all anticonvulsants showed flow-dependent characteristics. This is in line with our findings for basic drugs.  相似文献   
985.
Comorbidity between depression and tobacco use may reflect self-medication of serotonergically mediated mood dysregulation, which has been associated with aberrant cortical activation and hemispheric asymmetry in patients with major depressive disorders (MDD). This randomized, double-blind study in 28 remitted MDD patients examined the moderating effects of acute nicotine and smoker vs. nonsmoker status on mood and EEG changes accompanying transient reductions in serotonin induced by acute tryptophan depletion (ATD). In smokers, who exhibited greater posterior high alpha power and increased left frontal low alpha power (signs of deactivation) compared to nonsmokers, ATD increased self-ratings of depressed mood and elevated left frontal and right parietal high alpha power (i.e. further cortical deactivation). Smokers were not affected by nicotine administration. In nonsmokers, ATD did not influence depression ratings, but it reduced vigor ratings and increased frontal and posterior theta power; both of which were blocked by acute nicotine. These findings indicate a role for nicotinic receptors in disordered mood.  相似文献   
986.
987.
988.
ObjectiveThe 2-week-wait (2ww) referral pathway is used in England to fast-track patients with suspected colorectal cancer (CRC). A two-stage triage pathway was used to prioritise lower gastrointestinal (LGI) endoscopy for suspected CRC during the COVID-19 pandemic.MethodAll patients referred for an LGI endoscopy via a 2ww referral pathway between March 2020 and July 2020 were assessed. The first stage triaged patients to high, standard or low risk of CRC based on symptoms and faecal immunochemical test (FIT), and offered CT scans to those at high risk. The second stage, endoscopy prioritisation (EP), incorporated the CT results, FIT and symptoms to triage into four groups, EP1–EP4; with EP1 being the most urgent and EP4 the least. The primary outcome measure was CRC detection.Results514 patients were included. The risk of CRC was triaged as high in 190/514 patients (37%), standard in 274/514 patients (53%) and low in 50/514 (10%) patients. 422/514 patients (82%) underwent endoscopy with triage to EP1 in 52/422 (12%), EP2 in 105/422 (25%), EP3 in 210/422 (50%) and EP4 in 55/422 (13%). CRC was detected in 23 patients (5.4%). CRC was significantly more frequent in the EP1 group (23.1%, relative risk (RR)=16.2) and EP2 group (6.7%, RR=4.7) compared with EP3 group (1.4%). All CRC lesions were identified by CT imaging when performed prior to LGI endoscopy.ConclusionThis triage pathway designated 83% of patients with CRC to either EP1 or EP2. During a period of limited endoscopy provision, this pathway effectively prioritises endoscopy for those at greatest risk of CRC.  相似文献   
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