STUDY AND APPLICATION ON REAL TIME OPTIMUM OPERATION FOR PLANT UNITS

ABSTRACT The optimum unit commitment is to determine an optimal scheme which can minimize the system operating cost during a period while the load demand, operation constrains of the individual unit are simultaneously satisfied. Since it is characterized as a nonlinear, large scale, discrete, mixed-integer combinatorial optimization problem with constrains, it is always hard to find out the theoretical optimal solution. In this paper, a method combining the priority-order with dynamic comparison is brought out to obtain an engineering optimal solution, and is validated in a power plant composed of three 200MW and two 300MW units. Through simulating the on-line running datum from the DCS system in the power plant, the operating cost curves are obtained in different units, startup/shut-down mode and load demand. According to these curves, an optimum unit commitment model is established based on equal-incremental rate pnnciple principle. Make target function be minimum gross coal consumption, the results show that compared with the duty-chief-mode that allocates the load based on operators' experience, the units' mean gross coal consumption rate is reduced about 0.5g/(kWoh) when operating by this unit commitment model, and its economic profit is far more than the load economic allocation model that doesn't considered the units' start-up/shut-down

Changes in foveal avascular zone area and retinal vein diameter in patients with retinal vein occlusion detected by fundus fluorescein angiography

PurposeTo investigate changes in foveal avascular area (FAZ) and retinal vein diameter in patients with retinal vein occlusion (RVO) after intravitreal ranibizumab, and to analyze the correlation between ranibizumab therapy and visual gain.MethodsThis retrospective study enrolled 95 eyes of 95 patients who had accepted three consecutive monthly ranibizumab injections, including 50 branch RVOs (BRVOs) and 45 central RVOs (CRVOs). BRVOs were divided into ischemia group (n = 32) and non-ischemia group (n = 18), and CRVOs also had ischemia group (n = 28) and non-ischemia group (n = 17). Comprehensive ophthalmic examinations were performed before the first injection and after 6, 12, and 24 months. The FAZ was manually circumscribed on early-phase images of fundus fluorescein angiography. Retinal vein diameters were measured on fundus photographs.ResultsAfter three injections, the FAZ area was significantly enlarged firstly and then reduced in all ischemic RVOs and the non-ischemic BRVOs (p < 0.05), while the retinal vein diameter was significantly reduced firstly and then increased in all groups except for unobstructed branch veins of non-ischemic BRVOs (p < 0.05). The correlation between the FAZ area and best corrected visual acuity was statistically significant in all CRVOs (non-ischemic, r = 0.372; ischemic, r = 0.286; p < 0.01) and ischemic BRVOs (r = 0.180, p < 0.05). Spearman’s correlation analysis revealed that the retinal vein diameter was significantly correlated to the larger FAZ area in obstructed branch veins of ischemic BRVOs (r = −0.31, p < 0.01), inferior temporal branch veins of non-ischemic CRVOs (r = −0.461, p < 0.01) and ischemia CRVO groups (superior temporal branch vein, r = −0.226, p < 0.05; inferior temporal branch vein, r = −0.259, p < 0.01).ConclusionAfter three consecutive monthly ranibizumab injections, the FAZ area was enlarged and retinal vein diameter reduced with gradual recovery to near baseline from 12 months. These results suggest that ranibizumab therapy can worsen macular ischemia and prevent visual gain in the short term. It has important significance for the treatment and prognosis of RVO, although the natural course of RVO may also affect ischemia and visual gain

Numerical simulation of co-incineration of sewage sludge and municipal solid waste in municipal solid waste incinerator

Incineration is widely used as an important method of sludge and garbage utilization and harmless treatment. The simulations of co-incineration of sludge and municipal solid waste are conducted by computational fluid dynamics method(CFD) in a MSW incinerator. The study focuses on the effect of mixing proportion, moisture content of sludge, excess air coefficient and primary and secondary air distribution ratio on the combustion progress. Simulation results indicate that the combustion temperature of furnace decreases rapidly with the increase of the mixing proportion and moisture content of sludge, which is mainly because the moisture content of sludge is higher than that of MSW as well as its low calorific value. As a result, it is recommended that the water content and mixing ratio of sludge would be controlled below 40% and 7% respectively. Therefore, the fresh sludge should be dried before entering the furnace

Comparison of clinical efficacy and stability of Toric implantable collamer lens implantation in different orientations

AIM: To compare the clinical efficacy, vault, and rotational stability of horizontal, oblique, and vertical implantation of Toric implantable collamer lens(TICL).METHODS: Retrospective cohort study. A total of 92 cases(120 eyes)who underwent TICL implantation from July 2018 to March 2022 and had regular follow-up for at least 1 a postoperatively(1 d, 1 wk, 1, 3, 6 mo, and 1 a)at Wuhan Bright Eye Hospital were collected. The patients were divided into three groups, with 34 cases(45 eyes)in horizontal implantation group, 25 cases(29 eyes)in oblique implantation group(29 cases), and 33 cases(46 eyes)in vertical implantation group. Uncorrected distance visual acuity(UDVA), corrected distance visual acuity(CDVA), diopters, vault, and rotation angle(deviation of the actual axis of TICL from the expected axis).RESULTS: All surgeries were uneventful, and there were no complications such as infection, secondary glaucoma, or cataract opacity. Safety and efficacy of the surgery: the CDVA of the three groups of patients was better than or equal to the preoperative CDVA at 1 a postoperatively, and there was no statistically significant differences in postoperative UDVA and CDVA of the three groups(P>0.05). The safety index at 1a postoperatively was 1.34±0.21, 1.34±0.17, and 1.31±0.18 for the horizontal, oblique, and vertical groups, respectively. The efficacy index was 1.26±0.21, 1.33±0.18, and 1.27±0.16 for the three groups, respectively, both with no statistically significant differences(P>0.05). Vault: there was a significant difference in postoperative vault among the three groups(P=0.003), with the vertical group having the lowest vault, followed by the horizontal group and the oblique group. The vaults at different follow-up time points within each group showed significant differences(P<0.001), and all decreased over time. Residual astigmatism: there was no significant difference in residual astigmatism among the three groups(P=0.130), but there were differences at different follow-up time points within each group(P<0.001). Rotation angle: no significant differences in rotation angle were observed among the three groups(P=0.135), but there were differences at different follow-up time points within each group(P<0.001).CONCLUSION: The implantation of TICL in different orientations has good safety and efficacy, the postoperative rotational stability is good, and the appropriate angle can be selected to implant TICL according to the clinical situation

Nutrient intake and risk of multimorbidity: a prospective cohort study of 25,389 women

Abstract Background Multimorbidity is becoming an increasingly serious public health challenge in the aging population. The impact of nutrients on multimorbidity remains to be determined and was explored using data from a UK cohort study. Method Our research analysis is mainly based on the data collected by the United Kingdom Women’s Cohort Study (UKWCS), which recruited 35,372 women aged 35–69 years at baseline (1995 to 1998), aiming to explore potential associations between diet and chronic diseases. Daily intakes of energy and nutrients were estimated using a validated 217-item food frequency questionnaire at recruitment. Multimorbidity was assessed using the Charlson comorbidity index (CCI) through electronic linkages to Hospital Episode Statistics up to March 2019. Cox’s proportional hazards models were used to estimate associations between daily intakes of nutrients and risk of multimorbidity. Those associations were also analyzed in multinomial logistic regression as a sensitivity analysis. In addition, a stratified analysis was conducted with age 60 as the cutoff point. Results Among the 25,389 participants, 7,799 subjects (30.7%) were confirmed with multimorbidity over a median follow-up of 22 years. Compared with the lowest quintile, the highest quintile of daily intakes of energy and protein were associated with 8% and 12% increased risk of multimorbidity respectively (HR 1.08 (95% CI 1.01, 1.16), p-linearity = 0.022 for energy; 1.12 (1.04, 1.21), p-linearity = 0.003 for protein). Higher quintiles of daily intakes of vitamin C and iron had a slightly lowered risk of multimorbidity, compared to the lowest quintile. A significantly higher risk of multimorbidity was found to be linearly associated with higher intake quintiles of vitamin B12 and vitamin D (p-linearity = 0.001 and 0.002, respectively) in Cox models, which became insignificant in multinomial logistic regression. There was some evidence of effect modification by age in intakes of iron and vitamin B1 associated with the risk of multimorbidity (p-interaction = 0.006 and 0.025, respectively). Conclusions Our findings highlight a link between nutrient intake and multimorbidity risk. However, there is uncertainty in our results, and more research is needed before definite conclusions can be reached

Nel-like Molecule Type 1 Combined with Gold Nanoparticles Modulates Macrophage Polarization, Osteoclastogenesis, and Oral Microbiota in Periodontitis

The disruption of host–microbe homeostasis and uncontrolled inflammatory response have been considered as vital causes for developing periodontitis, subsequently leading to an imbalance between the bone and immune system and the collapse of bone homeostasis. Consequently, strategies to modulate the immune response and bone metabolization have become a promising approach to prevent and treat periodontitis. In this study, we investigated the cooperative effects of Nel-like molecule type 1 (Nell-1) and gold nanoparticles (AuNPs) on macrophage polarization, osteoclast differentiation, and the corresponding functions in an experimental model of periodontitis in rats. Nell-1-combined AuNPs in in vitro studies were found to reduce the production of inflammatory factors (TNF-α, p p = 0.0012), modulate the ratio of M2/M1 macrophages by inducing macrophage polarization into the M2 phenotype, and inhibit cell fusion, maturation, and activity of osteoclasts. Furthermore, the local application of Nell-1-combined AuNPs in in vivo studies resulted in alleviation of damages to the periodontal and bone tissues, modulation of macrophage polarization and the activity of osteoclasts, and alteration of the periodontal microbiota, in which the relative abundance of the probiotic Bifidobacterium increased (p < 0.05). These findings reveal that Nell-1-combined AuNPs could be a promising drug candidate for the prevention and treatment of periodontitis. However, Nell-1-combined AuNPs did not show organ toxicity or impair the integrity of intestinal epithelium but alter the gut microbiota, leading to the dysbiosis of gut microbiota. The adverse impact of changes in gut microbiota needs to be further investigated. Nonetheless, this study provides a novel perspective and direction for the biological safety assessment of biomaterials in oral clinical applications

Periodontitis salivary microbiota exacerbates colitis-induced anxiety-like behavior via gut microbiota

Abstract The gut–brain axis is a bidirectional communication system between the gut and central nervous system. Many host-related factors can affect gut microbiota, including oral bacteria, making the brain a vulnerable target via the gut–brain axis. Saliva contains a large number of oral bacteria, and periodontitis, a common oral disease, can change the composition of salivary microbiota. However, the role and mechanism of periodontitis salivary microbiota (PSM) on the gut–brain axis remain unclear. Herein, we investigated the nature and mechanisms of this relationship using the mice with dextran sulfate sodium salt (DSS)-induced anxiety-like behavior. Compared with healthy salivary microbiota, PSM worsened anxiety-like behavior; it significantly reduced the number of normal neurons and activated microglia in DSS mice. Antibiotic treatment eliminated the effect of PSM on anxiety-like behavior, and transplantation of fecal microbiota from PSM-gavaged mice exacerbated anxiety-like behavior. These observations indicated that the anxiety-exacerbating effect of PSM was dependent on the gut microbiota. Moreover, the PSM effect on anxiety-like behavior was not present in non-DSS mice, indicating that DSS treatment was a prerequisite for PSM to exacerbate anxiety. Mechanistically, PSM altered the histidine metabolism in both gut and brain metabolomics. Supplementation of histidine-related metabolites had a similar anxiety-exacerbating effect as that of PSM, suggesting that histidine metabolism may be a critical pathway in this process. Our results demonstrate that PSM can exacerbate colitis-induced anxiety-like behavior by directly affecting the host gut microbiota, emphasizing the importance of oral diseases in the gut–brain axis