Effects of different drying treatments on fungal population and ochratoxin A occurrence in sultana type grapes

This study aimed to determine the changes in mould and ochratoxin A (OTA) occurrence in sultanas under three different conventional drying conditions. Five different vineyards were chosen, and the three different treatments were applied to these grapes while drying. At the end of the drying process, total mould and black aspergilli (BA) populations in the samples varied from 2.45 to 5.61 log colony-forming units (CFU) g^–1 and from 0 to 4.92 log CFU g^–1, respectively. Significant increases (p < 0.05) occurred in mould loads depending on the extending drying period. However, independent of vineyard location, all the samples treated with cold dipping solution showed the lowest fungal loads. These results indicate that dipping solution treatment was the most effective drying method to minimise fungal infection of grapes. The expected results could not be achieved by drying grapes artificially contaminated with ochratoxigenic Aspergillus carbonarius spores. Seventy-one of 96 isolates (73.95%) obtained during drying were Aspergillus spp., and the remaining (n = 25, 26.05%) belonged to other genera, such as Penicillium, Trichoderma and Cladosporium. Grape juice-based agar medium was used to determine the realistic OTA production capacities of the isolated mould strains. The highest OTA production capacities were 809.70 ± 9.19, 87.58 ± 16.89 and 45.44 ± 18.78 ng g^–1 in 50% grape juice agar (GJ50), all five of which were from A. niger isolates. OTA was not present in any sample during the drying period; however, OTA was detected in two samples at 0.32 ± 0.15 and 0.52 ± 0.36 µg kg^–1 after the end of the drying process. The limit of detection (LOD) and limit of quantitation (LOQ) of the method used for detecting OTA in samples were 0.1 and 0.3 µg kg^–1, respectively.     

Synthesis,characterization and thermal properties of a novel star polymer consisting of poly(ε-caprolactone) arms emanating from an octa-functional porphyrazine core

Octaarmed star-shaped poly(ε-caprolactone) (OSPCL) was successfully synthesized via the ring-opening polymerization (ROP) of ε-caprolactone (ε-CL) with a magnesium porphyrazine as the multisite initiator and tin(II) 2-ethylhexanoate (Sn(Oct₂)) as the catalyst in bulk at 115 °C. The star polymer has a central Mg-porphyrazine surrounded by ε-CL arms. OSPCL was characterized by ¹H NMR, FTIR, GPC and UV–vis, and fluorescent spectroscopy. The effect of the molar ratio of the monomer to the initiator on molecular weight of the polymer was also investigated. The molecular weight of the polymer linearly increased with increasing molar ratio of the monomer to the initiator. The crystallization behavior of OSPCL was studied using differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). OSPCL displayed an interrupted crystal morphology owing to its highly branched architecture, and consequently, the degree of crystallinity was lower in comparison with the linear analogue. Thermogravimetric analysis (TGA) clearly indicated that incorporation of porphyrazine core enhanced the thermal stability of the resulting polymers.     

Psychological Symptoms Are Greater in Caregivers of Patients on Hemodialysis Than Those of Peritoneal Dialysis

Background: The purpose of this study was to evaluate and compare psychosocial characteristics in caregiving relatives (caregivers) of hemodialysis (HD) and peritoneal dialysis (PD) patients. Methods: Thirty‐three caregivers (17 women, 16 men) of HD patients, 27 caregivers (11 women, 16 men) of PD patients, and a control group of 49 subjects who do not care for family members with chronic illness (23 women, 26 men) are included in this study. The brief symptom inventory (BSI), social disability schedule (SDS), and brief disability questionnaire (BDQ) were used for the psychosocial evaluation. Results: The mean age, men‐to‐women ratios, duration of education, and distribution of marital status did not differ significantly among the three groups. In addition, dialysis duration and distribution of caregiver type were not different between the HD and PD groups. Although the mean global severity index scores of the three groups were similar, somatization and depression scores from BSI subitems were greater in the HD group than the scores of the PD and control groups. Although the mean SDS and BDQ scores were higher in the HD group, the differences did not achieve statistical significance. BSI subitems such as somatization, obsession–compulsion, interpersonal sensitivity, depression, and anxiety were positively correlated among themselves. Hostility and somatization were negatively correlated with age and education, respectively. Nevertheless, somatization was positively correlated with age. Social disability was negatively correlated with duration of education. Conclusion: Somatization and depression are greater in the caregivers of center HD patients compared to PD and control groups. According to the findings of this study, we suggest that caregiving family members of dialysis patients especially on HD also should be evaluated for psychosocial problems and supported as needed. Further studies are needed to explore whether psychosocial parameters of caregivers predict outcomes for caregivers and patients.     

Superparamagnetic flexible substrates based on submicron electrospun Estane® fibers containing MnZnFe?Ni nanoparticles

Flexible, elastomeric, and superparamagnetic substrates were prepared by electrospinning a solution of elastomeric polyurethane containing ferrite nanoparticles (～14 nm) of Mn? Zn? Ni. The flexible mats were characterized in terms of fiber morphology and magnetic properties. Field emission scanning electron microscopy (FESEM) indicated that the diameter of these composite fibers was ～300–500 nm. Furthermore, the back‐scattered electron FESEM images indicated agglomeration of the nanoparticles at higher wt % (ca. 17–26 wt %) loading in the electrospun fibers. The induced specific magnetic saturation and the relative permeability were found to increase linearly with increasing wt % loading of the ferrite nanoparticles on the submicron electrospun fibers. A specific magnetic saturation of 1.7–6.3 emu/g at ambient conditions indicated superparamagnetic behavior of these composite electrospun substrates. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4935–4942, 2006     

Production scheduling with uncertain supply: a new solution to the open pit mining problem

The annual production scheduling of open pit mines determines an optimal sequence for annually extracting the mineralized material from the ground. The objective of the optimization process is usually to maximize the total Net Present Value (NPV) of the operation. Production scheduling is typically a Mixed Integer Programming (MIP) type problem containing uncertainty in the geologic input data and economic parameters involved. Major uncertainty affecting optimization is uncertainty in the mineralized materials (resource) available in the ground which constitutes an uncertain supply for mine production scheduling. A new optimization model is developed herein based on two-stage Stochastic Integer Programming (SIP) to integrate uncertain supply to optimization; past optimization methods assume certainty in the supply from the mineral resource. As input, the SIP model utilizes a set of multiple, stochastically simulated scenarios of the mineralized materials in the ground. This set of multiple, equally probable scenarios describes the uncertainty in the mineral resource available in the ground, and allows the proposed model to generate a single optimum production schedule. The method is applied for optimizing the annual production scheduling at a gold mine in Australia and benchmarked against a traditional scheduling method using the traditional single “average type” assessment of the mineral resource in the ground. In the case study presented herein, the schedule generated using the proposed SIP model resulted in approximately 10% higher NPV than the schedule derived from the traditional approach.     

The relationship between energy and production: Evidence from Turkish manufacturing industry

This paper investigates the relationship between energy and production at the industry level in an emerging market, Turkey, in a multivariate framework. The electricity consumption and value added relation is examined in the Turkish manufacturing industry, while also accounting for labor and fixed investment. We find that labor, fixed investment, electricity consumption, and value added are related via three cointegrating vectors. The VEC results indicate uni-directional causality running from electricity consumption to value added. Generalized impulse response and variance decomposition analyses confirm these results. Thus, energy input appears to be closely related to production. Hence, energy saving technologies and increased energy efficiency may increase the growth in manufacturing value added.     

A Simple,Low-Cost,and Useful Preconcentration Method for Quantification of Soluble,Insoluble, and Total Oxalate in Selected Vegetables Through Spectrophotometry

The amount of dietary oxalate from food may be an important risk factor in the development of idiopathic calcium oxalate nephrolithiasis. The main aim of this research was to develop an accurate and reliable method by cloud point extraction (CPE) combined with spectrophotometry to measure the oxalate contents of selected vegetables. The method is based on ion association of stable anionic complex, which is produced by the reaction of oxalate with Mo(VI), with Toluidine blue (TBH²⁺), and then by extraction into micelles of octylphenol ethoxylate (Triton X-45) in the presence of NH₄F as a salting-out agent at pH 6.0. Using the optimized conditions, the calibration graph was highly linear in the range of 1.2–240 μg L^?1. The detection limit of the method (LOD (3σ _blank/m) was 0.36 μg L^?1, and the relative standard deviation (RSD %) as a measure of precision was in the range of 1.1–5.3 % (n?=?5 for 5, 25, and 50 μg L^?1). The method was successfully applied to the speciative determination of soluble and total oxalate in vegetables after ultrasonic-assisted extraction and dilution at suitable ratios. The amount of insoluble oxalate was calculated from the analytical difference between total oxalate and soluble oxalate contents of samples with and without acidic extraction under ultrasonic power (300 W, 50 Hz) for 15 min at 60 °C. The accuracy of the method was intrinsically controlled and verified by comparing the results obtained with those of an independent kinetic method as well as recoveries of spiked samples.

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Graphical Abstract Experimental steps of the proposed method

     

Micellar sensitized catalytic kinetic spectrophotometry for highly accurate and reproducible determination of V（IV） and V（V）

A highly accurate and reproducible micellar sensitized kinetic method was proposed for determination of V（VI）. The method is based on its catalytic effect on the oxidation of Coomassie brilliant blue R 250 （CBB＋） by bromate at pH 2.0. The reaction was monitored spectro- photometrically by measuring absorbance change with a fixed-time method of 5 min at 594 and 552 nm with and without surfactant. The variables influencing the calibra- tion sensitivity were extensively investigated, and the optimal conditions were established. The linear calibration range was 10-1,600 μg.L-1 with a relative SD ranging from 0.35 % to 3.35 % （for five replicate measurements of 75, 500, 1,000, and 1,500 μg.L-1） and a detection limit of 3.8 μg.L-1. The selectivity was also investigated, and greatly enhanced by suitable masking agents. The method was successfully applied to the analysis of V（IV） in pre- sence of excess V（V） up to 25 fold in environmental waters with the recoveries of 100.0 %-102.8 % for V（IV） and 95.7 %-99.7 % for total V. Its accuracy was validated by analysis of certified reference material via the present kinetic method and standard flame atomic absorption spectrometric method after extractive preconcentration with good agreement between certified and found values.     

Thermodegradation of Poly(4-Vinylpyridine-co-Maleic Acid-co-Divinylbenzene) and N-oxide Derivatives: Modeling of TG and DTG Curves

Copolymer networks based on 4-vinylpyridine (4VPy)/maleic acid (MA)/divinylbenzene (DVB) and their N-oxide derivatives have been investigated by thermogravimetric analysis (TG) to evaluate their thermal stability in nitrogen atmosphere at fixed heating rate. Thermal stability was determined from TG curves to investigate the influence of 4VPy content and introduction of N-oxide groups. The TG and DTG curves of unmodified copolymers clearly show one thermodegradation stage and the same kinetic pathway. The decomposition temperatures do not depend on the 4VPy content. The copolymers modified by oxidation present lower thermostability than unmodified showing that the introduction of N-oxide groups modifies their kinetic pathways. A kinetic model Ozawa was used to determine the kinetic parameters. The apparent thermal decomposition activation energies (Δ E _d) of the unmodified copolymer under nitrogen was higher than that in modified copolymer.