The relation among achievement goals and academic achievement in statistics: the mediating role of statistics anxiety and statistics self-efficacy

AbstractIn order to predict student's academic achievement in statistics in terms of achievement goals, statistics anxiety and statistics selfefficacy, 323 participants from Fars Peyame Noor Universities were selected via multi- stage cluster sampling and then were asked to fill in a set of questionnaires, consisted of achievement goals, statistics anxiety and statistics self-efficacy scales. Results of path analysis generally showed that achievement goals indirectly and through statistics anxiety and statistics self-efficacy affect students’ achievement in statistics. Moreover, results showed that unlike avoidance-performance goals, the indirect effect of mastery goals on statistical achievement is positive

Assessing the quality of sardine based on biogenic amines using a fuzzy logic model

There is an increasing concern about the quality and quality assessment procedures of seafood. In the present study, a model to assess fish quality based on biogenic amine contents using fuzzy logic model (FLM) is proposed. The fish used was sardine (Sardinella sp.) where the production of eight biogenic amines was monitored over fifteen days of storage at 0, 3 and 10°C. Based on the results, histamine, putrescine and cadaverine were selected as input variables and twelve quality grades were considered for quality of fish as output variables for the FLM. Input data were processed by rules established in the model and were then defuzzified according to defined output variables. Finally, the quality of fish was evaluated using the designed model and Pearson correlation between storage times with quality of fish showed r=0.97, 0.95 and 1 for fish stored at 0, 3 and 10°C, respectively

The SALSAC Approach: Comparing the reactivity of solventdispersed nanoparticles with nanoparticulate surfaces

We demonstrate that the 'surface-as-ligand, surface-as-complex' (SALSAC) approach that we have established for annealed nanoparticulate TiO2 surfaces can be successfully applied to nanoparticles (NPs) dispersed in solution. Commercial TiO2 NPs have been activated by initial treatment with aqueous HNO3 followed by dispersion in water and heating under microwave conditions. We have functionalized the activated NPs with anchoring ligands 1-4; 1-3 contain one or two phosphonic acid anchoring groups and 4 has two carboxylic acid anchors; ligands 1, 2 and 4 contain 6,6'-dimethyl-2,2'-bipyridine (Me2bpy) metal binding domains and 3 contains a 2,2':6',2"-terpyridine (tpy) unit. Ligand functionalization of the activated NPs has been validated using infrared and 1H NMR spectroscopies, and thermogravimetric analysis. NPs functionalized with 1, 2 and 4 react with [Cu(MeCN)4][PF6] and those with 3 react with FeCl2 .4H2O; metal binding has been investigated using solid-state absorption spectroscopy and scanning electron microscopy (SEM). Competitive binding of ligands 1-4 to TiO2 NPs has been investigated and shows preferential binding of phosphonic acid over carboxylic acid anchors. For the phosphonic acids, the binding orders are 3 > 1 > 2 which is rationalized in terms of relative pKa values (phosphonic acid and [HMe2bpy]+ or [Htpy]+) and the number of anchoring groups in the ligands. Ligand exchange between ligandfunctionalized NPs and homoleptic metal complexes gives NPs functionalized with heteroleptic copper(I) or iron(II) complexe

Changes in urocanic acid, histamine, putrescine and cadaverine levels in Indian mackerel (Rastrelliger kanagurta) during storage at different temperatures

Histamine, putrescine cadaverine and cis-urocanic acid (UCA) have all been implicated or suggested in scombroid fish poisoning. However, there is little information on UCA especially during storage. Changes in their contents during storage of whole Indian mackerel at 0, 3 ± 1, 10 ± 1 for up to 15 days and 23 ± 2 °C for up to 2 days were monitored. Fresh muscles contained 14.83 mg/kg trans-UCA, 2.23 mg/kg cis-UCA and 1.86 mg/kg cadaverine. Histamine and putrescine were not detected. After 15 days at 0 and 3 °C, trans-UCA content increased to 52.83 and 189.51 mg/kg, respectively, and decreased to <2 mg/kg at the other two temperatures. Storage at 10 °C also resulted in an increase in trans-UCA after 3 days, only to decrease after 6 days. The concentration of cis-UCA increased nearly 13-fold after 15 days at 0 and 3 °C, decreased at 10 °C and remained unchanged at 23 °C. Histamine, putrescine and cadaverine levels increased significantly (P value < 0.05) at all temperatures especially at 23 °C

Bioinformatics prioritization of SNPs perturbing microRNA regulation of hematological malignancy-implicated genes.

The contribution of microRNAs (miRNAs) to cancer has been extensively investigated and it became obvious that a strict regulation of miRNA-mRNA regulatory network is crucial for safeguarding cell health. Apart from the direct impact of miRNA dysregulation in cancer pathogenesis, genetic variations in miRNAs are likely to disrupt miRNA-target interaction. Indeed, many evidences suggested that SNPs within miRNA regulome are associated with the development of different hematological malignancies. However, a full catalog of SNPs within miRNAs target sites of genes relevant to hematopoiesis and hematological malignancies is still lacking. Accordingly, we aimed to systematically identify and characterize such SNPs and provide a prioritized list of most potentially disrupting SNPs. Although in the present study we did not address the functional significance of these potential disturbing variants, we believe that our compiled results will be valuable for researchers interested in determining the role of target-SNPs in the development of hematological malignancies

Determination of trans- and cis-urocanic acid in relation to histamine, putrescine, and cadaverine contents in tuna (Auxis thazard) at different storage temperatures

Scombroid fish poisoning is usually associated with consumption of fish containing high levels of histamine. However, reports indicate that some cases have responded to antihistamine therapy while ingested histamine levels in these cases were low. Potentiation of histamine toxicity by some biogenic amines, and release of endogenous histamine by other compounds such as cis-urocanic acid (UCA) are some hypotheses that have been put forth to explain this anomaly. Very little is known about the effects of storage conditions on the production of both UCA isomers and biogenic amines in tuna. Thus, the production of trans- and cis-UCA, histamine, putrescine, and cadaverine in tuna during 15 d of storage at 0, 3, and 10 °C and 2 d storage at ambient temperature were monitored. The initial trans- and cis-UCA contents in fresh tuna were 2.90 and 1.47 mg/kg, respectively, whereas the levels of putrescine and cadaverine were less than 2 mg/kg, and histamine was not detected. The highest levels of trans- and cis-UCA were obtained during 15 d storage at 3 °C (23.74 and 21.79 mg/kg, respectively) while the highest concentrations of histamine (2796 mg/kg), putrescine (220.32 mg/kg) and cadaverine (1045.20 mg/kg) were obtained during storage at room temperature, 10 and 10 °C, respectively. Histamine content increased considerably during storage at 10 °C whereas trans- and cis-UCA contents changed slightly. The initial trans-UCA content decreased during storage at ambient temperature. Thus, unlike histamine, concentrations of trans- and cis-UCA did not result in elevated levels during storage of tuna

The relationship between mental workload and general health among welders of Tehran Heavy Structure Metal Company

Mental workload is one of the factors that influence individuals’ performance in the work environment as well as their efficiency and productivity. The present study aimed at examining the association between mental workload and general health among welders of Tehran Heavy Structuress Metal Company.This cross-sectional study was conducted in 2016. The sample included 100 welders who were working in Tehran Heavy Structures Metal Company. Sampling was done through conducting a census. A demographic questionnaire, General Health Questionnaire-28 (GHQ-28), and National Aeronautics and Space Administration Task Load Index (NASA-TLX) mental workload questionnaire were used to collect data. The obtained data were fed into SPSS (version 22) and analyzed through Chi-square, one-way ANOVA, Kruscal Wallis Test, Pearson product moment correlation, and Mann-Whitney U Test.The results showed that the participating welders had an average age of 36.16±7.81, an average work experience of 9.65±5.83, and a BMI of 25.95±3.39 kg/m2. The mean and standard deviation of the overall score of welders’ mental workload were 65.88±21.15. The cut-off scores for the total mental workload questionnaire and the subscales were respectively set at 23 and 6. The results demonstrated that 26% of the welders were suspected of mental disorder. Furthermore, the results of Pearson correlation indicated that there was no significant relationship between the overall score of NASA mental workload and that of general health (p-value&gt;0.05).Welders’ mental workload is relatively high. Therefore, further research should be conducted in order to identify main risk factors that lead to mental and health disorder. Future studies should also be performed to present some solutions for te purpose of decreasing or preventing these side effects among welders as much as possible.

The manner of urocanic acid accumulation in fish by tracking histidine ammonia lyase activity during storage of vacuum-packed, eviscerated, and whole fish

Accumulation of urocanic acid (UCA) in stored fish has been attributed to both endogenous and exogenous histidine ammonia lyase (HAL) activity. The level of HAL in Indian mackerel, tuna, and sardine were monitored at different temperatures. It was also evaluated during storage of eviscerated and whole fish under vacuum packaging. UCA production in sardine was also evaluated during storage. The highest and the lowest activity of HAL in fresh fish was observed in Indian mackerel and tuna (26.32 and 9.94 Unit/g, respectively). Endogenous HAL was the main agent of UCA accumulation at 0°C while it was not the only effective factor. The main agent of UCA accumulation in fish depended on the kind of fish which was important during long storage at low temperatures. Results also indicated that unlike evisceration, vacuum packaging was effective on decrease and control of HAL content during storage of fish

Disentangling Light- and Temperature-Induced Thermal Effects in Colloidal Au Nanoparticles

We present temperature-dependent (from room temperature to 80 \ub0C) absorption spectra of Au/SiO2 core-shell nanoparticles (NPs) (core diameter: 3c25 nm) in water in the range from 1.5 to 4.5 eV, which spans the localized surface plasmon resonance (LSPR) and the interband transitions. A decrease in absorption with temperature over the entire spectral range is observed, which is more prominent at the LSPR. These changes are well reproduced by theoretical calculations of the absorption spectra, based on the experimentally measured temperature-dependent real (\u3f51) and imaginary (\u3f52) parts of the dielectric constant of Au NPs and of the surrounding medium. In addition, we model the photoinduced response of the NPs over the entire spectral range. The experimental and theoretical results of the thermal heating and the simulations of the photoinduced heating are compared with the ultrafast photoinduced transient absorption (TA) spectra upon excitation of the LSPR. These show that while the latter is a reliable monitor of heating of the NP and its environment, the interband region mildly responds to heating but predominantly to the population evolution of charge carriers

Growth kinetics and characterization of human dental pulp stem cells: comparison between third molar and first premolar teeth

Dental pulp stem cells (DPSCs) play an important role in tissue regeneration. This study compares the growth kinetics and characterization of third molar and first premolar human DPSCs. Dental pulp tissues were isolated from human first premolar and third molar teeth and were digested by treating them with collagenase type I. Single-cell suspensions from each dental pulp were seeded in T25 culture flasks and the media were replaced every 3 days until 70% confluence. The cells were enumerated to determine the population doubling time (PDT). Cells were characterized using flow cytometry, RT-PCR and osteogenic medium for differentiation of DPSCs. Karyotyping assay was also performed till passage 7th. The DPSCs had spindle-shaped morphology. There was an increase in PDT in third molar DPSCs when compared to first premolar teeth. Positive expression of CD44, CD73, and CD90 and negative expression of CD34 and CD45 were illustrated. A normal karyotype was visible for all seven passages. The Alizarin red staining was positive for osteogenic induction of DPSCs. When DPSCs are needed, third molar teeth can be a good and convenient candidate for cell transplantation, yielding high number of cells with mesenchymal characteristics. They can be a source for further investigations in vitro and work on tissue engineering protocols