Evolutionary multi-objective optimal control of combined sewer overflows

This paper presents a novel multi-objective evolutionary optimization approach for the active control of intermittent unsatisfactory discharges from combined sewer systems. The procedure proposed considers the unsteady flows and water quality in the sewers together with the wastewater treatment costs. The distinction between the portion of wastewater that receives full secondary treatment and the overall capacity of the wastewater treatment works (including storm overflow tanks) is addressed. Temporal and spatial variations in the concentrations of the primary contaminants are incorporated also. The formulation is different from previous approaches in the literature in that in addition to the wastewater treatment cost we consider at once the relative polluting effects of the various primary contaminants in wastewater. This is achieved by incorporating a measure of the overall pollution called the effluent quality index. The differences between two diametrically opposed control objectives are illustrated, i.e. the minimization of the pollution of the receiving water or, alternatively, the minimization of the wastewater treatment cost. Results are included for a realistic interceptor sewer system that show that the combination of a multi-objective genetic algorithm and a stormwater management model is effective. The genetic algorithm achieved consistently the frontier optimal control settings that, in turn, revealed the trade-offs between the wastewater treatment cost and pollution of the receiving water

Effect of serviceability limits on optimal design of steel portal frames

The design of hot-rolled steel portal frames can be sensitive to serviceability deflection limits. In such cases, in order to reduce frame deflections, practitioners increase the size of the eaves haunch and / or the sizes of the steel sections used for the column and rafter members of the frame. This paper investigates the effect of such deflection limits using a real-coded niching genetic algorithm (RC-NGA) that optimizes frame weight, taking into account both ultimate as well as serviceability limit states. The results show that the proposed GA is efficient and reliable. Two different sets of serviceability deflection limits are then considered: deflection limits recommended by the Steel Construction Institute (SCI), which is based on control of differential deflections, and other deflection limits based on suggestions by industry. Parametric studies are carried out on frames with spans ranging between 15 m to 50 m and column heights between 5 m to 10 m. It is demonstrated that for a 50 m span frame, use of the SCI recommended deflection limits can lead to frame weights that are around twice as heavy as compared to designs without these limits

Pressure-dependent EPANET extension

In water distribution systems (WDSs), the available flow at a demand node is dependent on the pressure at that node. When a network is lacking in pressure, not all consumer demands will be met in full. In this context, the assumption that all demands are fully satisfied regardless of the pressure in the system becomes unreasonable and represents the main limitation of the conventional demand driven analysis (DDA) approach to WDS modelling. A realistic depiction of the network performance can only be attained by considering demands to be pressure dependent. This paper presents an extension of the renowned DDA based hydraulic simulator EPANET 2 to incorporate pressure-dependent demands. This extension is termed “EPANET-PDX” (pressure-dependent extension) herein. The utilization of a continuous nodal pressure-flow function coupled with a line search and backtracking procedure greatly enhance the algorithm’s convergence rate and robustness. Simulations of real life networks consisting of multiple sources, pipes, valves and pumps were successfully executed and results are presented herein. Excellent modelling performance was achieved for analysing both normal and pressure deficient conditions of the WDSs. Detailed computational efficiency results of EPANET-PDX with reference to EPANET 2 are included as well

Utjecaj klimatskih promjena na proizvodnju riže u Adamawi, Nigerija

This study analyzes the effect of climate change on rice production in Adamawa State, Nigeria. The study describes the trend in rice production and determines the factors affecting the output of rice in Adamawa. Secondary data from 1990-2015 was used. The analytical tools used were descriptive analysis, unit root and regression analysis. The result of the study reveals that there is variation in the trend of the climatic factors affecting rice production in Adamawa State. The findings reveal that rainfall and minimum temperature are the major climatic factors that affect the rice production; such that 1% increase in rainfall leads to 22.2% increase in rice production and 1% increase in minimum temperature leads to 3.7% reduction in rice production. Therefore rainfall is found to be positively significant to rice output, while minimum temperature is found to be negatively significant. The study therefore recommends that irrigation facilities should be built, especially in the north where drought threatens food production. Also breeders should develop rice varieties that have less gestation period and can survive high temperature.Ovaj se rad bavi utjecajem klimatskih promjena na proizvodnju riže u Adamawi, Nigerija. Opisuju se trendovi rasta i pada proizvodnje te određuju faktori koji utječu na količinu proizvedene riže. Istraživanje se temelji na sekundarnim podacima iz razdoblja od 1990. do 2015. Za analizu su korištene sljedeće metode: deskriptivna analiza, test jediničnog korijena i regresijska analiza. Rezultati dobiveni istraživanjem pokazuju da klimatski faktori utječu na proizvodnju riže u Adamawi, a kao glavni među njima ističu se količina padalina i minimalna temperatura: porast u količini padalina od 1 % rezultira porastom u proizvodnji riže od 22.2 %, a porast minimalne temperature od 1 % rezultira padom u proizvodnji riže od 3.7 %. Iz toga se može zaključiti da postoji pozitivna korelacija između količine padalina i količine proizvedene križe te negativna korelacija s obzirom na minimalnu temperaturu. S obzirom na dobivene rezultate preporučuje se izgradnja objekata za navodnjavanje, osobito na sjeveru gdje su sušna razdoblja prijetnja proizvodnji hrane. Također, uzgajivačima se preporuča razvoj vrsta riže koje imaju kraći gestacijski period te mogu preživjeti više temperature

Sex differences in chronic kidney disease prevalence in Asia: a systematic review and meta-analysis

Background Previous reports on the prevalence of chronic kidney disease (CKD) in Asia have suggested important sex disparities but have been inconsistent in nature. We sought to synthesize available sex-disaggregated CKD prevalence data in Asia to quantify sex disparities in the region. Methods We systematically searched MEDLINE and Embase for observational studies involving ≥500 adults who reported sex-disaggregated CKD prevalence data in any of the 26 countries in East, Southeast and South Asia. For each study we calculated the female:male prevalence ratio (PR), with a ratio >1 indicating a higher female prevalence. For each country, log-transformed PRs were pooled using random effects meta-analysis. These were then combined using a fixed effects model, weighting by population size, to estimate a pooled PR for each of East, Southeast and South Asia and Asia overall. Results Sex-disaggregated data were available from 171 cohorts, spanning 15 countries and comprising 2 550 169 females and 2 595 299 males. Most studies (75.4%) came from East Asia (China, Taiwan, Japan and South Korea). Across Asia, CKD prevalence was higher in females {pooled prevalence 13.0% [95% confidence interval (CI) 11.3–14.9]} compared with males [pooled prevalence 12.1% (95% CI 10.3–14.1)], with a pooled PR of 1.07 (95% CI 0.99–1.17). Substantial heterogeneity was observed between countries. The pooled PRs for East, Southeast and South Asia were 1.11 (95% CI 1.02–1.21), 1.09 (0.88–1.36) and 1.03 (0.87–1.22), respectively. Conclusions Current evidence suggests considerable between-country and -region heterogeneity in the female:male PR of CKD. However, there remains a large part of the region where data on sex-specific CKD prevalence are absent or limited. Country-level assessment of the differential burden of CKD in females and males is needed to define locally relevant policies that address the needs of both sexes

Small nucleoli are a cellular hallmark of longevity

Animal lifespan is regulated by conserved metabolic signalling pathways and specific transcription factors, but whether these pathways affect common downstream mechanisms remains largely elusive. Here we show that NCL-1/TRIM2/Brat tumour suppressor extends lifespan and limits nucleolar size in the major C. elegans longevity pathways, as part of a convergent mechanism focused on the nucleolus. Long-lived animals representing distinct longevity pathways exhibit small nucleoli, and decreased expression of rRNA, ribosomal proteins, and the nucleolar protein fibrillarin, dependent on NCL-1. Knockdown of fibrillarin also reduces nucleolar size and extends lifespan. Among wildtype C. elegans, individual nucleolar size varies, but is highly predictive for longevity. Long-lived dietary restricted fruit flies and insulin-like-peptide mutants exhibit small nucleoli and fibrillarin expression, as do long-lived dietary restricted and IRS1 knockout mice. Furthermore, human muscle biopsies from individuals who underwent modest dietary restriction coupled with exercise also display small nucleoli. We suggest that small nucleoli are a cellular hallmark of longevity and metabolic health conserved across taxa

Perturbation of adhesion molecule-mediated chondrocyte-matrix interactions by 4-hydroxynonenal binding: implication in osteoarthritis pathogenesis

ABSTRACT: INTRODUCTION: Objectives were to investigate whether interactions between human osteoarthritic chondrocytes and 4-hydroxynonenal (HNE)-modified type II collagen (Col II) affect cell phenotype and functions and to determine the protective role of carnosine (CAR) treatment in preventing these effects. METHODS: Human Col II was treated with HNE at different molar ratios (MR) (1:20 to 1:200; Col II:HNE). Articular chondrocytes were seeded in HNE/Col II adduct-coated plates and incubated for 48 hours. Cell morphology was studied by phase-contrast and confocal microscopy. Adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) and alpha1beta1 integrin at protein and mRNA levels were quantified by Western blotting, flow cytometry and real-time reverse transcription-polymerase chain reaction. Cell death, caspases activity, prostaglandin E2 (PGE2), metalloproteinase-13 (MMP-13), mitogen-activated protein kinases (MAPKs) and nuclear factor-kappa B (NF-kappaB) were assessed by commercial kits. Col II, cyclooxygenase-2 (COX-2), MAPK, NF-kappaB-p65 levels were analyzed by Western blotting. The formation of alpha1beta1 integrin-focal adhesion kinase (FAK) complex was revealed by immunoprecipitation. RESULTS: Col II modification by HNE at MR approximately 1:20, strongly induced ICAM-1, alpha1beta1 integrin and MMP-13 expression as well as extracellular signal-regulated kinases 1 and 2 (ERK1/2) and NF-kappaB-p65 phosphorylation without impacting cell adhesion and viability or Col II expression. However, Col II modification with HNE at MR approximately 1:200, altered chondrocyte adhesion by evoking cell death and caspase-3 activity. It inhibited alpha1beta1 integrin and Col II expression as well as ERK1/2 and NF-kappaB-p65 phosphorylation, but, in contrast, markedly elicited PGE2 release, COX-2 expression and p38 MAPK phosphorylation. Immunoprecipitation assay revealed the involvement of FAK in cell-matrix interactions through the formation of alpha1beta1 integrin-FAK complex. Moreover, the modification of Col II by HNE at a 1:20 or approximately 1:200 MR affects parameters of the cell shape. All these effects were prevented by CAR, an HNE-trapping drug. CONCLUSIONS: Our novel findings indicate that HNE-binding to Col II results in multiple abnormalities of chondrocyte phenotype and function, suggesting its contribution in osteoarthritis development. CAR was shown to be an efficient HNE-snaring agent capable of counteracting these outcomes

Prolonged Application of High Fluid Shear to Chondrocytes Recapitulates Gene Expression Profiles Associated with Osteoarthritis

BACKGROUND: Excessive mechanical loading of articular cartilage producing hydrostatic stress, tensile strain and fluid flow leads to irreversible cartilage erosion and osteoarthritic (OA) disease. Since application of high fluid shear to chondrocytes recapitulates some of the earmarks of OA, we aimed to screen the gene expression profiles of shear-activated chondrocytes and assess potential similarities with OA chondrocytes. METHODOLOGY/PRINCIPAL FINDINGS: Using a cDNA microarray technology, we screened the differentially-regulated genes in human T/C-28a2 chondrocytes subjected to high fluid shear (20 dyn/cm(2)) for 48 h and 72 h relative to static controls. Confirmation of the expression patterns of select genes was obtained by qRT-PCR. Using significance analysis of microarrays with a 5% false discovery rate, 71 and 60 non-redundant transcripts were identified to be ≥2-fold up-regulated and ≤0.6-fold down-regulated, respectively, in sheared chondrocytes. Published data sets indicate that 42 of these genes, which are related to extracellular matrix/degradation, cell proliferation/differentiation, inflammation and cell survival/death, are differentially-regulated in OA chondrocytes. In view of the pivotal role of cyclooxygenase-2 (COX-2) in the pathogenesis and/or progression of OA in vivo and regulation of shear-induced inflammation and apoptosis in vitro, we identified a collection of genes that are either up- or down-regulated by shear-induced COX-2. COX-2 and L-prostaglandin D synthase (L-PGDS) induce reactive oxygen species production, and negatively regulate genes of the histone and cell cycle families, which may play a critical role in chondrocyte death. CONCLUSIONS/SIGNIFICANCE: Prolonged application of high fluid shear stress to chondrocytes recapitulates gene expression profiles associated with osteoarthritis. Our data suggest a potential link between exposure of chondrocytes/cartilage to abnormal mechanical loading and the pathogenesis/progression of OA