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As two of the most abundant and destructive salts in nature, sodium and magnesium sulfates can affect the physico-mechanical characteristics of stones and, thus, their durability. In this paper, the effects of these salts are compared on some physico-mechanical characteristics of travertine, including point load index (PLI), Brazilian tensile strength (BTS), P-wave velocity (Vp), and porosity (n). For this purpose, a travertine sample was obtained from the Abasabad quarry in Mahallat (central Iran) and transferred to the laboratory. Next, salt crystallization tests in sodium and magnesium sulfate solutions were carried out for up to 30 cycles. Afterward, PLI, BTS, Vp, and n of the sample were measured after every 5 cycles of the salt crystallization test. The decay constant (λ), half-time (N1/2), and the rate of loss (RL) were used to compare the effects of sodium and magnesium sulfates on the PLI, BTS, Vp, and n of the sample. Here, λ and N1/2 were obtained from regression curves developed between the measured PLI, BTS, Vp, and n with cycles of salt crystallization tests. The RL and N1/2 of the PLI, BTS, Vp, and n show that the durability of the sample subjected to the salt crystallization tests in sodium and magnesium sulfates was different. The results indicate that the effect of sodium sulfate on the PLI, BTS, Vp, and n of the sample was more severe than that of magnesium sulfate. Generally, PLI, BTS, Vp, and n not only indicate visible changes occurring in the sample due to salt crystallization action (e.g., mass loss, powdering, pitting, and detachments) but also show its inner microstructural modifications due to pores development. In addition, the PLI, BTS, Vp, and n can be good indicators for preventive and monitoring purposes and suitable tools for uncovering the initial stages of building stones' deterioration subjected to salt crystallization action. These parameters are vital when it is not possible to detect the changes in the inner structure of building stones with the naked eye. [ABSTRACT FROM AUTHOR]

Background: Foeniculum vulgare, F. vulgare, commonly known as fennel, is believed to be one of the world's oldest medicinal herbs and has been exploited by people for centuries as a nutritional aid for digestive disorders. In many southeast Asian countries, it is ingested as an after-meal snack, mukhvas, due to its breath-freshening and digestive aid properties. F. vulgare is used in some countries, such as Iran, as a complementary and alternative treatment for inflammatory bowel disease (IBD). Methods: This study investigated the effects of fennel seed extract on intestinal epithelium barrier function and the Signal Transducer and Activator of Transcription (STAT) pathway. This pathway is active in inflammatory bowel disease. To study the protective effects of fennel seed extract in vitro, monolayers derived from the T84 colonic cell line were challenged with interferon-gamma (IFN-γ) and monitored with and without fennel seed extract. To complement our in vitro studies, the dextran sodium sulfate induced murine colitis model was employed to ascertain whether the protective effect of fennel seed extract can be recapitulated in vivo. Results: Fennel seed extract was shown to exert a protective effect on transepithelial electrical resistance (TEER) in both T84 and murine models and showed increases in tight junction-associated mRNA in T84 cell monolayers. Both models demonstrated significant decreases in phosphorylated STAT1 (pSTAT1), indicating reduced activation of the STAT pathway. Additionally, mice treated with fennel seed showed significantly lower ulcer indices than control mice. Conclusions: We conclude barrier function of the gastrointestinal tract is improved by fennel seed extract, suggesting the potential utility of this agent as an alternative or adjunctive therapy in IBD. [ABSTRACT FROM AUTHOR]

Formaldehyde is a colorless and highly irritating substance that is used as a preservative and chemical fixative in tissue processing in pathological laboratories. Formaldehyde is mutagenic and is classified by the IARC as the definitive carcinogen (A1 group). This cross-sectional descriptive-analytical study was performed to determine the respiratory exposure of 60 employees of pathology labs with formaldehyde and to estimate carcinogenic and non-carcinogenic risk in Iran in 2018–2019. Occupational exposure to formaldehyde was assessed in summer season using the NIOSH 3500 method and a personal sampler with flow of 1 l/min connected to two Glass Midget Impingers containing 20 ml of 1% sodium bisulfate solution. The respiratory symptoms questionnaire provided by the American Thoracic Society was used to assess the health effects of formaldehyde exposure. The carcinogenic and non-carcinogenic risk assessment of inhaled exposure to formaldehyde was also performed using the USA Environmental Protection Agency (OEHHA) method. The mean respiratory exposure of employees to formaldehyde was 0.64 mg/m3 (range: 0.1474 to 1.3757). Occupational exposure in 28.3% (n = 17) of employees was above the OSHA recommended range. Wheezing (24%), burning eyes (25%), and cough (21.7%) were the most prevalent health problems. The mean ± SD of the carcinogenic risk among the employees was 3.45 × 10−4 ± 2.27 × 10−4. The highest mean of carcinogenic risk was found in lab workers (4.44 × 10−4). Given the high level of carcinogenic and non-carcinogenic risk of respiratory exposure to formaldehyde in pathological employees, especially lab worker, the use of management controls, engineering controls, and respiratory protection equipment to reduce exposure levels of all workers to less than the allowed exposure limits seems necessary. [ABSTRACT FROM AUTHOR]

The basic principle of Doolittle multivariate calibration algorithm (DMCA) was investigated and used for simultaneous quantitative determination of sodium tripolyphosphate (STPP), sodium sulfate (SS), and sodium carbonate (SC) in commercial washing powders with serious overlapping. The process of the Doolittle decomposition algorithm (DDA) is implemented by lower and upper (LU) triangular matrix decomposition which is robust and convenient. Then it was applied to overcome the problem of overlapping spectra of different components in the detergent washing powder. The root mean square error of prediction (RMSEP) for DMCA is 0.084 which confirms the improvement in accuracy, in comparison with K-Matrix (KM) (RMSEP=0.118). It was demonstrated that DDA can avoid matrix inverting, reduce the orders of matrices, and needs a little time for analysis. Therefore, it has bright prospects in chemometrics and it is feasible that the Doolittle algorithm could be applied to the practical determinations in real samples with spectral overlapping. [ABSTRACT FROM AUTHOR]

The chemical composition of the hydrodistilled essential oil of the air-dried aerial parts of Haplophyllum robustum growing wild in Iran was obtained by hydrodistillation and was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The species is poor in essential oil (yield = 0.5%). Thirty constituents representing 99.23% of total oil have been identified. The main constituents of the oil were found to be 1,8-cineole (38.1%), Myrcene (10.69 %), α-Pinene (8.46%), 4-Terpineol (6.96%) and Sabinene (6.15%). Other representative compounds were identified as Methyl geranat (4.69%), γ-terpinen (4.3%) and α-terpinene (3.43%). [ABSTRACT FROM AUTHOR]

The article focuses on the study which examines the level of organochlorine pesticides (OCP) contaminants in adipose tissues collected from humans in Tebriz, Iran from 1991-1992. The study involved 61 patients that underwent surgeries, from whom adipose tissues were collected. It conducted analysis with methods, such as gas chromatography (GC), anhydrous sodium sulphate and Mann-Whitney test. Results show that hexachlorobenzene (HCB) residues are the main contaminants for the subjects.

The essential oil of Pycnocycla nodiflora Decne. ex Boiss. growing wild in Iran was obtained by hydrodistallation and analyzed by GC and GC/MS technique. Seventy-two components representing 86.8% of the total oil were identified. The main components of the oil were β-eudesmol (34.3%), hexadecanoic acid (11.5%) and spathulenol (6.9%). [ABSTRACT FROM AUTHOR]

• A safflower-based biorefinery co-producing bioethanol and biodiesel was developed. • Ethanol production by Z. mobilis and S. cerevisiae was techno-economically compared. • Ethanol production using Z. mobilis was economically-justified for implementation. • Z. mobilis lowered both ethanol production cost and minimum ethanol selling price. Safflower plant is a promising energy crop, which is compatible with arid and semi-arid climate conditions. This study is set to perform a techno-economic assessment of an integrated biorefinery located in Iran, using safflower seed and safflower straw as feedstock for production of bioethanol as the main product, biodiesel as the most valuable byproduct while biogas, glycerol, solid residue, and sodium sulfate are the other valuable byproducts. In the first Scenario (A), glucose, xylose, and arabinose are fermented into ethanol by using Zymomonas mobilis produced in a seed train unit. While in the other Scenario (B), Saccharomyces cerevisiae is supplied externally by a yeast production facility and is used to ferment glucose into ethanol. Both scenarios are simulated using Aspen Plus software and a cash flow analysis is performed using well-known economic indices for the biofuel industry presented by the National Renewable Energy Laboratory. The profitability index is 1.14 for Scenario A, showing its cost-effectiveness. However, this index is found to be 0.81 for Scenario B, revealing the fact that this approach is not economically-justified for implementation. More specifically, the use of Z. mobilis instead of S. cerevisiae as fermenting microorganism enhances the profitability of the project by lowering ethanol production cost from 0.12 $/L to 0.09 $/L and minimum ethanol selling price from 0.67 $/L to 0.43 $/L. Moreover, in both scenarios, biodiesel production boosts the total annual sale values by 39% and 55% for scenario A and B, respectively. In general, 1.86 and 2.44 times improvements in this economic index are respectively obtained for scenario A and B because of byproduct credits. The outcomes of sensitivity analysis also shows that the discount factor and safflower seed price have large impacts on the profitability of the developed biorefineries. Overall, Z. mobilis appears to be a preferred biocatalyst for bioethanol fermentation through the biorefinery platform from the techno-economic viewpoint. [ABSTRACT FROM AUTHOR]

Hydrogeochemical investigation of groundwater in the Kaboudar Ahang, Hamedan, western Iran was carried out to assess chemical composition of groundwater having complex contamination sources. The chemical compositions of the groundwater are dominated by Na+, Cl- and SO2- 4 . The predominant water type of groundwater samples are the NaCl (59%) and NaSO4 (38%) facies. Both Na+ and Cl- +SO2- 4 account for 56 and 61% of the total cations and anions. Contamination of groundwater appeared to be affected by the solubility of mineral phases and discharge of sewage effluent, and agricultural activities. Anthropogenic inputs into the groundwater mainly include Na+, Cl- and SO2- 4 according to chemical compositions of sewage effluent. Continuous disposal of sewage effluent from power plant (which contains appreciable amounts of Na+ ions) through irrigation in closed systems poses a serious threat of soil and groundwater sodification. [ABSTRACT FROM AUTHOR]