[Factors Affecting Nitrate Concentrations and Nitrogen and Oxygen Isotope Values of Effluents from Waste Water Treatment Plant].

Urban domestic sewage is one of the important nitrate (NO-3) sources for surface water; however, their NO-3 concentrations and nitrogen and oxygen isotope values (δ15N-NO-3 and δ18O-NO-3) remain unclear, and the factors affecting NO-3 concentrations and δ15N-NO-3 and δ18O-NO-3 values of effluents in the waste water treatment plant (WWTP) are still unknown. Water samples in the Jiaozuo WWTP were collected to illustrate this question. Influents, clarified water in the secondary sedimentation tank (SST), and effluents of the WWTP were sampled every 8 h. The ammonia (NH+4) concentrations, NO-3 concentrations, and δ15N-NO-3 and δ18O-NO-3 values were analyzed to elucidate the nitrogen transfers through different treatment sections and illustrate the factors affecting the effluent NO-3 concentrations and isotope ratios. The results indicated that ① the mean NH+4 concentration was (22.86±2.16) mg·L-1 in the influent and decreased to (3.78±1.98) mg·L-1 in the SST and continuously reduced to (2.70±1.98) mg·L-1 in the effluent of the WWTP. The median NO-3 concentration was 0.62 mg·L-1 in the influent, and the average NO-3 concentration increased to (33.48±3.10) mg·L-1 in the SST and gradually increased to (37.20±4.34) mg·L-1 in the effluent of the WWTP. ② The mean values of δ15N-NO-3 and δ18O-NO-3 were (17.1±10.7)‰ and (19.2±2.2)‰ in the influent of the WWTP, the median values of δ15N-NO-3 and δ18O-NO-3 were 11.9‰ and 6.4‰ in the SST, and the average values were (12.6±1.9)‰ and (5.7±0.8)‰ in the effluent of the WWTP. ③ The NH+4 concentrations of influent had significant differences compared to those in the SST and the effluent (P<0.05). The reduction of NH+4 concentrations in the SST was due to the above nitrification during the aerobic treatment process, which transferred NH+4 to NO-3. The NH+4 concentrations in the SST had no significant differences with that in the effluent of the WWTP (P>0.05). ④ The NO-3 concentrations in the influent had significant differences with those in the SST and the effluent (P<0.05), and minor NO-3 concentrations but relatively high δ15N-NO-3 and δ18O-NO-3 values in the influent were probably due to denitrification during the pipe sewage transportation. The obviously increased NO-3 concentrations (P<0.05) but decreased δ18O-NO-3 values (P<0.05) in the SST and the effluent resulted from water oxygen incorporation during the nitrification. The above results confirmed the impacts of aerobic and anaerobic treatment processes on NO-3 concentrations and isotope ratios of effluent from the WWTP and provided scientific basis for the identification of sewage contributions to surface water nitrate via average δ15N-NO-3 and δ18O-NO-3 values.

[Systematic Evaluation of Low-carbon Operation of Typical A2O Processes in Municipal Sewage Plant].

Under the "Carbon Peak, Carbon Neutral" goal, the systematic evaluation of the carbon emission equivalent (CO2eq) and its compositions of the typical A2O process has important guiding significance for the low-carbon operation of most municipal sewage plants in China. Based on the operational data on the first municipal sewage plant of Jiaozuo in 2020 and the methods presented in "2019 Refinement to the 2006 IPCC Guidelines for National Greenhouse Gas Inventories, " a systematic evaluation of the CO2eq of the typical A2O process was established, including direct emissions that were built on the Arrhenius model introducing the water temperature factor and indirect emissions from the three aspects of electricity consumption, agent addition, and sludge transportation. The results showed that the daily emission intensities of CH4 and N2O were (115±56) kg·d-1 and (30±18) kg·d-1, respectively. Additionally, indirect carbon emissions from electricity consumption and agent addition accounted for 48.4% and 51.3% in the biochemical treatment section, respectively. In 2020, CO2eq amounts of total research plant and per unit sewage were 2.17×104 t and (0.63±0.07) kg·m-3, respectively. The magnitude of the proportion of different carbon emission compositions was as follows:sewage electricity (36.5%)>sewage agent (26.6%)>N2O direct (15.4%)>sludge agent (9.6%)>sludge electricity (6.7%)>CH4 direct (4.9%)>sludge transportation (0.3%). System import/export fluxes of carbon and nitrogen elements were calculated, followed by the carbon to nitrogen mass ratio in the sewage plant. Direct carbon emission characteristics of CH4 and N2O and their influencing factors were discussed, respectively. Based on the balance theory of carbon and nitrogen elements in the system, it is proposed that the selective introduction of industrial wastewater may become an important reference measure for the low-carbon operation of municipal sewage plants in the future.

An alarm device for mechanical compression device displacement at femoral artery puncture sites.

OBJECTIVE: To develop an alarm device for the mechanical compression device displacement (MCD), and further evaluate its effectiveness in clinical use. MATERIAL AND METHODS: The alarm device is mainly composed of buzzer, indicator light, magnetic sheet. This is a prospective randomized and controlled study. Four hundred patients who met the inclusion/exclusion criteria were included and randomly assigned to two groups (MCD group vs alarm + MCD group). The primary outcome measures were the sensitivity and specificity of the alarm device to detect MCD displacement, time to hemostasis (TTH), time to ambulation (TTA), time to hospital discharge (TTHD), hospital costs (HC), complication rates, and patient satisfaction. RESULTS: The sensitivity and specificity of the alarm device in detecting MCD displacement were 94.44% and 88.46%, respectively. The study group achieved shorter TTH (p = .034), shorter TTA (p = .021), lower complication rates (p = .025), and better patients' satisfaction (p < .001) compared to the control group. However, no significant difference was observed in TTHD (p = .361) and HC (p = .583). CONCLUSION: The alarm device is highly sensitive in detecting MCD displacement, while achieving better clinical outcomes compared with artificial monitoring.

Nurses' knowledge and attitudes on comfort nursing care for hospitalized patients.

To investigate the knowledge and attitudes of practicing nurses on comfort care for hospitalized patients, a survey was conducted in 311 registered nurses from a major teaching hospital. A total of 212 (68.1%) of the participants showed an adequate knowledge of comfort care. Participants who had 6 years or more working experience returned a higher mean scores on physiological and psychological aspects of comfort care (P < 0.05). The total scores were the highest among participants from intensive care unit and the lowest among participants from the oncology department. Although 282 (90.7%) participants were involved in comfort care, only 210 (67.5%) received formal hospital-based training in this practice. We conclude that there was a large difference in the knowledge between nurses from different departments on comfort care. Continuing education programmes are required to improve the knowledge and skills in comfort care.

Correlation between serum high-mobility group box-1 levels and high-sensitivity C-reactive protein and troponin I in patients with coronary artery disease.

The aim of this study was to evaluate the correlation between levels of serum high-mobility group box-1 (HMGB1) and high-sensitivity C-reactive protein (hs-CRP) and cardiac troponin I in patients with coronary artery disease. The levels of serum HMGB1, hs-CRP and cardiac troponin I were measured in 98 patients with coronary artery disease and in 30 healthy subjects. The correlation between serum HMGB1 levels and hs-CRP and cardiac troponin I levels was analyzed. Serum HMGB1 levels in patients with coronary artery disease were higher compared with those in healthy volunteers (63.5±15.29 vs. 21.98±4.33 µg/l; P<0.01). Serum HMGB1 levels in patients with acute myocardial infarction were higher compared with those in patients with unstable and stable angina pectoris (77.53±6.86 vs. 63.67±8.6 and 44.39±9.01 µg/l, respectively; both P<0.01). The levels of HMGB1 were positively correlated with hs-CRP and cardiac troponin I levels (r=0.657 and 0.554, respectively; both P<0.01) in patients with coronary artery disease. In conclusion, serum HMGB1 levels were elevated in patients with coronary artery disease, particularly in those with acute myocardial infarction. The levels of HMGB1 were correlated with the levels of hs-CRP and cardiac troponin I.

Prognostic values of serum tenascin-C in patients with ischaemic heart disease and heart failure.

OBJECTIVE: The aim of this study was to evaluate the prognostic values of serum tenascin-C in patients with heart failure and ischaemic heart disease. METHODS: Serum tenascin-C levels were assessed in 83 patients with heart failure and in 30 healthy subjects. The correlations between serum tenascin-C levels and left ventricular ejection fraction, serum B-type natriuretic peptide and procollagen III were analysed. Patients were followed up for 12 months, and the relations between the serum levels of tenascin-C and cardiac events (re-hospitalisation for worsening heart failure and mortality) were analysed. RESULTS: Serum tenascin-C levels in patients with heart failure were higher than in healthy volunteers (72.24 ± 11.02 vs. 22.78 ± 2.51 µg/L, p<0.01). Serum tenascin-C levels in patients of NYHA class IV were higher than in patients with NYHA class II (88.56 ± 3.73 vs. 64.88 ± 3.15 µg/L, p<0.01). The levels of tenascin-C were negatively correlated with the left ventricular ejection fraction (r=-0.636, p<0.01), but were positively correlated with serum B-type natriuretic peptide (r=0.553, p<0.01) or procollagen III levels (r=0.665, p<0.01). An increased level of tenascin-C was an independent predictor for combined re-hospitalisation and mortality (OR 1.22, 95% CI: 0.86-2.14). CONCLUSION: Serum tenascin-C levels were elevated in patients with heart failure. The levels of tenascin-C were associated with the severity of left ventricular dysfunction and 12-month major adverse cardiac events.

Antihypertensive effect of total flavonoid fraction of Astragalus complanatus in hypertensive rats.

The purpose of the present study was to quantify the antihypertensive effect of the total flavonoid (TF), extracted from the seed of Astragalus complanatus R. Brown, and to observe its effect on the renin-angiotensin system (RAS) in both renal hypertensive rats (RHR) and spontaneously hypertensive rats (SHR). RHR were created by the two-kidney one clip (2K1C) method. Systolic blood pressure was measured in conscious rats by the tail-cuff method. Plasma angiotensin II (AngII) and plasma renin activity (PRA) were measured with radioimmunoassay at 60 min after drug administration. The effects of TF on cardiac hemodynamics were also recorded in anesthetized RHR and SHR. TF was given by oral administration in low dose (100 mg/kg) and high dose (200 mg/kg) respectively. Compared to pre-administration control, TF induced an obvious decrease in systolic blood pressure in conscious normotensive Wistar rat, RHR and SHR. In the three groups the systolic blood pressure reached the lowest value at 60 min after TF. TF also induced a significant decrease in blood pressure in anesthetized RHR and SHR. At 60 min after treatment of TF, mean arterial pressure in high dose group (200 mg/kg) was decreased by 17% in RHR and by 17% in SHR respectively (P < 0.01). The depressor effect of TF lasted for at least 60 min. Cardiac output, heart rate and +/- dp/dtmax did not change. Conversely, total peripheral resistance was significantly decreased. The decrease in plasma AngII was found in both RHR and SHR. On the contrary, PRA increased at the same time. These findings suggested that TF is effective in reducing blood pressure in both RHR and SHR. The antihypertensive action of TF was attributed to a decrease in TPR secondary to a decrease in plasma concentration of AngII caused by TF.