The dynamic behavior of a multiple dividing‐wall column pilot plant is evaluated by means of dynamic simulation. Three different control structures are developed or adapted from the literature, which ...are constrained by the actual design features of the pilot plant column. Since in the present case the design of the column was chosen such that very different mixtures can be separated, it cannot be optimally designed for each of these potential mixtures. Rather, the design focused on the flexibility of the plant. All three investigated control structures were tested on feed flow rate and feed composition disturbance and allowed a robust control of the pilot plant, whereby control structure 2 is slightly better than others in terms of steady‐state deviations and less pronounced fluctuations during the dynamic phase. The transferability of control structure 2 to other variants of multiple dividing‐wall columns is easily possible.
Multiple dividing‐wall columns offer high investment and energy cost savings in distillation. To ensure these savings during operation, robust control structures must be applied. Three basically simple and practical control structures were investigated for a simplified multiple dividing‐wall column. All three control structures allow a robust control of the laboratory column.
U ovom radu istražuju se mogućnosti vođenja kompleksne konfiguracije destilacijske kolone s razdjelnim stijenkama (KRS) za četiri proizvoda. Simulacijski su ispitane dvije izvedbe sustava za vođenje. ...Na temelju statičkog modela destilacijske kolone razvijene su dinamičke simulacije tih dviju izvedba, a njihov učinak testiran je uvođenjem poremećaja u sustav. Rezultati pokazuju da je za uspješno vođenje i postizanje zahtijevane kvalitete proizvoda potrebna vrlo čvrsta regulacija temperaturnih profila unutar kolone, ali i da je to moguće postići konvencionalnim metodama vođenja, odnosno primjenom regulacije PID.
Ovo djelo je dano na korištenje pod licencom Creative Commons Imenovanje 4.0 međunarodna .
Karst aquifers are globally important source of drinking water and harbor specific ecosystems that are vulnerable to anthropogenic contamination. This paper provides insights into the occurrence and ...ecotoxicological characterization of 21 emerging contaminants (ECs) detected in the karst catchment of Jadro and Žrnovnica springs (Dinarides, Croatia). Karst springs used for water supply, surface water, and groundwater were sampled during seven campaigns. The ECs concentration levels ranged from 0.3 ng/L (tramadol in Jadro spring) to 372 ng/L (1H-benzotriazole in Cetina River). DEET was the most frequently detected ECs with an average concentration of around 50 ng/L in both surface water and groundwater. To prioritise detected ECs, their persistence (P), bioaccumulation (B), mobility (M) and toxicity (T) were assessed based on in silico strategy for PBT assessment and recently developed REACH PMT guidelines. PBT scores ranging below the threshold of 0.5, indicated non-PBT compounds of expected low concern. However, only 4 out of 21 detected ECs were not assessed as PMT/vPvM. Concerningly, 20 ECs were categorised as very mobile. Karst springs exhibited larger proportions of ECs meeting PMT/vPvM criteria than surface water. To characterise the contamination extent and estimate the incidence of adverse effects of detected ECs, a preliminary environmental risk assessment (ERA) was conducted. Most ECs posed no environmental risk with RQ values predominantly below 0.01. The total risk quotient RQsite accentuated Cetina River as having the highest risk compared to other sampling sites. This is the first study on ECs in Croatian karst, contributing to a growing need to understand the impacts of emerging contaminants in karst aquifers, which are still largely unexplored.
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•Karst catchments harbor specific ecosystems vulnerable to artificial contamination.•Identification of 21 emerging contaminants at ng/L levels in karst catchment•Compounds were assessed as non-persistent-bioaccumulative-toxic (non-PBT).•Only 4 out of 21 compounds were not assessed as PMT/vPvM.•Caffeine posed the highest risk and Cetina River had a moderate site risk quotient.
Emerging organic contaminants (EOCs) are a vast group of often (very)persistent, (very)mobile and toxic (PMT/vPvM) substances that are continuously released worldwide, posing environmental and human ...health risks. Research on occurrence and behavior of EOCs in karst is in its infancy, thus policy measures and legislative control of these compounds in groundwater are still lacking. The Dinaric karst aquifers are an essential source of drinking water for almost half of Croatia's territory. Intense karstification, complex heterogeneous characteristics, and high fracture-cavernous porosity result in rapid, far-reaching groundwater flow and large karst springs, but also high intrinsic vulnerability due to low contaminant attenuation. To prioritize future monitoring and establish appropriate thresholds for EOCs detected in Croatian karst drinking water resources, in silico tools based on quantitative structure-activity relationships were used in PBT (persistence, bioaccumulation, and toxicity) and PMT/vPvM analyzes, while toxicological assessment helped identify potential threats to human health. In 33 samples collected during two sampling campaigns in 2019 at 16 karst springs and one lake used for water supply, we detected 65 compounds (EOCs and some legacy chemicals), of which 7 were classified as potentially PBT or vPvB compounds (PFOS, PFHxS, PFHpA, PFOA, PFNA, boscalid, and azoxystrobin), while only 2 compounds were assessed as not PMT/vPvM. This finding underlines that most of detected EOCs potentially endanger karst (ground)water ecosystems and important drinking water sources in Croatia. Comparison of maximum concentrations with existing or derived drinking water guideline values revealed how 2 of 65 detected compounds represent a potential risk to human health at lifelong exposure (sulfadiazine and hydrochlorothiazide), while 5 chemicals warrant additional human health impacts studies and groundwater monitoring. Although most compounds do not individually pose a significant risk to human health at current environmental levels, their potential synergistic and long-term effects remain unknown.
This study examined the hepatoprotective and anti-inflammatory effects of anthocyanins from Vaccinim myrtillus (bilberry) fruit extract on the acute liver failure caused by carbon tetrachloride-CCl4 ...(3 mL/kg, i.p.). The preventive treatment of the bilberry extract (200 mg anthocyanins/kg, orally, 7 days) prior to the exposure to the CCl4 resulted in an evident decrease in markers of liver damage (glutamate dehydrogenase, sorbitol dehydrogenase, malate dehydrogenase), and reduced pro-oxidative (conjugated dienes, lipid hydroperoxide, thiobarbituric acid reactive substances, advanced oxidation protein products, NADPH oxidase, hydrogen peroxide, oxidized glutathione), and pro-inflammatory markers (tumor necrosis factor-alpha, interleukin-6, nitrite, myeloperoxidase, inducible nitric oxide synthase, cyclooxygenase-2, CD68, lipocalin-2), and also caused a significant decrease in the dissipation of the liver antioxidative defence capacities (reduced glutathione, glutathione S-transferase, and quinone reductase) in comparison to the results detected in the animals treated with CCl4 exclusively. The administration of the anthocyanins prevented the arginine metabolism’s diversion towards the citrulline, decreased the catabolism of polyamines (the activity of putrescine oxidase and spermine oxidase), and significantly reduced the excessive activation and hyperplasia of the Kupffer cells. There was also an absence of necrosis, in regard to the toxic effect of CCl4 alone. The hepatoprotective mechanisms of bilberry extract are based on the inhibition of pro-oxidative mediators, strong anti-inflammatory properties, inducing of hepatic phase II antioxidant enzymes (glutathione S-transferase, quinone reductase) and reduced glutathione, hypoplasia of Kupffer cells, and a decrease in the catabolism of polyamines.
Karst catchments are valuable drinking water sources and fragile habitats to many endemic species. This dataset presents initial insights into the occurrence and ecotoxicological risk of 21 emerging ...contaminants (ECs) (including 11 pharmaceuticals, 4 lifestyle products, 2 personal care products, 3 agricultural and 1 industrial compound) detected in Dinaric karst catchment of Jadro and Žrnovnica springs in Croatia. Contaminants concentrations were determined with UHD Q-TOF LC/MS and UHP LC/MS in samples from two springs (Jadro and Žrnovnica), one river (Cetina), and a deep borehole (Gizdavac). Persistence (P), bioaccumulation (B), mobility (M) and toxicity (T) of detected ECs were assessed based on in silico strategy for PBT assessment and recently developed REACH PMT/vPvM guidelines. Risk quotients were calculated from PNEC values and measured contaminants’ concentrations. In addition, physicochemical properties (estimated and existing experimental values of solubility in water, log KOW, log KOC, and pKa) of detected substances and water (measured values of temperature and electrolytic conductivity) are provided. This dataset could be useful for setting up the regular monitoring and improvement of existing water-related legislative, water safety plans, for modelling contaminant transport and identification of potential sources, and lastly for comparison with other studies conducted in karst aquifers.
The present dataset was interpreted and discussed in the article entitled “Ecotoxicological aspects related to the occurrence of emerging contaminants in the Dinaric karst aquifer of Jadro and Žrnovnica springs” by Selak et al. (2022).
Holistic methods, such as biocrystallization and capillary dynamolysis, can be used to confirm differences in chemical composition between organic and conventionally produced milk. The utilization of ...such methods is complementary to other quality assurance methods and demonstrates a complex aspect of food quality. In this study, biocrystallization was used as a method for distinguishing between organic and conventionally produced pasteurized milk, demonstrating how the differences in the dairy cow feeding regime can affect milk properties. The biocrystallization was performed by means of copper (II) chloride dihydrate (CuCl2*2H2O). The biocrystallization patterns obtained from the conventional and organic milk samples were readily distinguished. A significant indication of differences was the emergence of degradation features in the biocrystallization patterns. While degradation features do not appear in organic milk, conventional milk showed clear indications of degradation, although the compound analysis of the two milks indicated no differences. From the morphological perspective, the biocrystallization patterns of organic milk have fared better according to all criteria. The results of the fatty acid analysis in milk from conventional and certified organic farms showed a greater content of beneficial fatty acids in organic milk: oleic (P<0.05), linoleic and linolenic (P<0.01). The analysis of animal feed indicated a higher content of cellulose, i.e. acid detergent fibers (ADF), and a lower content of neutral detergent fibers (NDF) in the organic animal feed. It was concluded that the method of copper chloride biocrystallization can determine the differences between pasteurized conventional and organic milk, which is greatly important in assuring the consumers of the milk origin, since the organic chain implies the increased quality control of soil, animal feed, animals and final dairy products with added value.
Soluble c-erbB-2 oncoprotein has been proven as a useful marker in the management of breast cancer patients, but its value in diagnostics and follow-up of colorectal cancer patients remains ...controversial. The aim of this study was to evaluate the usefulness of serum c-erbB-2 monitoring in diagnostics and prediction of disease outcome in rectal cancer patients.
Serum samples from 88 patients with rectal adenocarcinoma before surgery and from 41 healthy controls were tested for the presence of c-erbB-2 oncoprotein by ELISA, and the patients were followed up for at least 5 years after the surgery.
Preoperative serum c-erbB-2 levels were significantly higher in stage IV patients than in healthy controls (P<0.001) and did not show correlation with preoperative CEA levels. Elevated preoperative serum c-erbB-2 levels showed relatively high specificity (88%) and low sensitivity (44%) in the diagnosis of rectal cancer. Elevated preoperative oncoprotein levels were predictive neither for overall survival nor for development of local recurrence/distant metastases.
Although preoperative serum c-erbB-2 levels were significantly higher in rectal cancer patients than in healthy controls, the soluble c-erbB-2 does not seem to be useful in the diagnosis of rectal cancer due to its low sensitivity. Preoperative serum levels of this oncoprotein were predictive neither for overall survival nor for local recurrence/distant metastases in rectal cancer patients.
Background/Aim. Infantile hypertrophic pyloric stenosis (IHPS) is the most common cause of surgery in newborns and young infants. Conservative treatment of IHPS is of great importance because it ...spares the newborn from stress caused by surgery and general anesthesia. The aim of this study was to evaluate the impact of various oral administration regimens of atropine on its efficacy in treating IHPS. Methods. The study included 45 patients with IHPS, conservatively treated by atropine sulfate in the period from 2006 to 2016. Clinical examination, laboratory analysis, and ultrasonography were performed on all patients on admission. The efficacy of treatment with different oral dosage regimens was analyzed and potential predictive factors of the negative outcome were defined. The evaluation of the success of the treatment was statistically analyzed by the method of the multivariate logistic regression model. Results. Out of 45 patients, 36 (80%) were successfully cured (p = 0.0008, without the need for surgery and without any complications. Gender prevalence, age, birth weight, body weight on admission, duration of symptoms, pyloric muscle thickness, and length had no statistically significant individual effect on the success of the atropine treatment. Patients who received a progressively increased dose of atropine had an 18 times higher risk of surgery, patients with hypochloremic alkalosis (HCA) had a 15 times higher risk, while others, with more than 5 vomitings within the first three days of the therapy, were 9 times more likely to be surgically treated. Conclusion. High success rate and no side effects represent an orally administered atropine treatment as a valid alternative choice for non-operative management of IHPS. Administration of initially high doses was shown to be more effective in relation to gradually increased oral doses of atropine sulfate. HCA and continued vomiting are considered as potential predictive factors of negative outcomes of the atropine treatment.
The aim of this study was to estimate the total lifetime milk production and non additive genetic effects (recombination and heterosis) of cows with different proportions of Holstein-Friesian genes, ...obtained from the Serbian Fleckvieh (SF) and the Holstein-Friesian (HF) crossbreeding program in Vojvodina. Upgrading of local breeds with the Holstein-Friesian breed in Vojvodina started in 1971 and continued 2008. Six genotypes of cows (F1, R1, R2, R3, R4, R5) were obtained with increasing percentage of Holstein genes, in order to attain purebred Holstein cows. Of all obtained genotypes, cows of genotype R4 with a proportion of Holstein genes from 96.87 % had the highest lifetime milk production (20000 kg), followed by cows R3 with 19950 kg (93.75 % HF genes) and cows R5 with 19850 kg (98.44 % HF genes). Finally the process of upgrading resulted in pure Holsteins with 19780 kg of milk. The total lifetime production of milk fat did not show statistically significant difference (P>0.05) among the genotypes R1 - R5 which ranged from 675 to 690 kg. The pure Holstein obtained after sixth intermediate generations had the average lifetime milk fat production of 690 kg. With the increase in the proportion of Holstein-Friesian genes percentage of milk fat was decreased, so that the cows of genotypes R3, R4, R5 and pure Holsteins, had less than 3.5 % milk fat. In relation to the total milk yield, the highest realized heterosis effect was observed in the cows of F1 generation (hRF1=594 kg), while the lowest was observed in generation R2 (hRR2=72 kg), where negative effect of recombination was also found (hIR2=-77 kg). Positive values of the actual and relative of heterosis effect of the milk fat yield was observed in all genotypes, whereas the negative heterosis effect of the milk fat percentage was observed also in all genotypes, with the exception of R1 and R2 cows, in which the typical consequence of the positive recombination in the early crossed Holstein-generations was manifested.
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