Solubility of potassium ferrate in 12 M alkaline solutions between 20°C and 60°C

The solubility of potassium ferrate (K₂FeO₄) was measured in aqueous solutions of NaOH and KOH of total concentration 12 M containing various molar ratios of KOH:NaOH in the range 12:0 to 3:9. Several analytical methods were tested for the determination of ferrate concentration. The final method chosen consisted of potentiometric titration of the ferrate sample with an alkaline solution of As₂O₃. The assumption was made that ferrate dissociates in concentrated KOH solutions predominantly to KFeO₄⁻. The solubility constant, S, defined as the product of the molar concentration of the potassium ion, K⁺, and the ferrate anion, KFeO₄⁻, was found to be 0·044 ± 0·006 mol² dm⁻⁶ for 20°C, 0·093 ± 0·004 mol² dm⁻⁶ for 40°C and 0·15 ± 0·09 mol² dm⁻⁶ for 60°C. From these results the heat of dissolution of K₂FeO₄ was calculated as −14·3 kJ mol⁻¹. At 60°C the enhanced decomposition of the ferrate at the higher temperature led to a greater deviation in solubility values compared with data for either 20°C or 40°C.     

Neglected Facts on Mycobacterium Avium Subspecies Paratuberculosis and Type 1 Diabetes

Civilization factors are responsible for the increasing of human exposure to mycobacteria from environment, water, and food during the last few decades. Urbanization, lifestyle changes and new technologies in the animal and plant industry are involved in frequent contact of people with mycobacteria. Type 1 diabetes is a multifactorial polygenic disease; its origin is conditioned by the mutual interaction of genetic and other factors. The environmental factors and certain pathogenetic pathways are shared by some immune mediated chronic inflammatory and autoimmune diseases, which are associated with triggers originating mainly from Mycobacterium avium subspecies paratuberculosis, an intestinal pathogen which persists in the environment. Type 1 diabetes and some other chronic inflammatory diseases thus pose the global health problem which could be mitigated by measures aimed to decrease the human exposure to this neglected zoonotic mycobacterium.     

Preservation of biological materials under desiccation

A number of life forms, including seeds, certain nematodes, bacterial and fungal spores, and cysts of certain crustaceans, show an ability to survive desiccation. The present article reviews the literature available on this subject and critically evaluates the evidence for various mechanisms that may be responsible for these phenomena. Specific mechanisms considered include vitrification (glass formation) by sugars and other polyhydroxy compounds that are accumulated by the desiccated structures, specific effects of polyhydroxy compounds on membranes, effect of “compatible solutes” on conformation of key proteins, as well as other biochemical mechanisms.

The article presents potential applications relevant to food technology and to biotechnology and reviews the research required to materialize more effective use of desiccation in food and biopreservation.     

Putative virulence factors of the Aeromonas spp. isolated from food and environment in Abu Dhabi, United Arab Emirates

Thirty randomly selected Aeromonas isolates from food and the environment in Abu Dhabi, United Arab Emirates, were characterized for putative virulence determinants, such as production of cytotoxin, cytotonic toxin, and hemolysin and their capacity to adhere to and invade Henle 407 cells in vitro. Seventy percent of the tested isolates were cytotoxin producers, and 80% were hemolytic. Cytotoxin was produced by 6 of 7 A. hydrophila strains, 6 of 13 A. caviae strains, and 6 of 7 A. veronii bv. sobria strains, mostly from food sources. A. schubertii, A. jandaei, and A. trota also produced both cytotoxin and hemolysin. All of the 30 isolates tested adhered to Henle 407 cells, but none were able to invade the cells, as determined with the in vitro assay. However, no significant correlation of the presence of these putative virulence factors was found among these aeromonad food isolates.     

Determination of Antioxidant Activity and Polyphenols Content in Chips by Raman and IR Spectroscopy

The application of vibrational spectroscopy for the determination of total polyphenols content, antioxidant activity, colour parameters, and fat level in chips originated from yellow-, red- and purple-fleshed potato varieties is reported. Raman, infrared (IR) and near-infrared (NIR) spectra of the laboratory-prepared chips were collected. Combining spectral data with the results of reference analyses, partial least squares regression models were built. To characterise and compare the elaborated models, the relative standard errors of prediction were calculated for calibration and validation sets. In the case of total phenolics quantification by Raman/IR/NIR techniques, these errors (%) amounted to 4.0/7.0/7.1 and 6.4/8.5/8.4 for calibration and validation samples, respectively, whereas they were 4.9/7.7/4.8 and 6.6/8.3/6.8 for antioxidant activity. The obtained results demonstrate that both infrared and Raman spectroscopy can effectively replace commonly used extraction methods. It follows that Raman spectroscopy has the highest potential to be adopted for the online potato-derived product analysis.     

Dynamic mechanical behaviour of random copolymers of a LC-methacrylate and octyl methacrylate

The dynamic mechanical behaviour of random copolymers of LC monomer-1-(hexyloxycarbonyl)ethyl 4-[4-(methacryloyloxy)benzoyloxy]benzoate (HB) and octyl methacrylate (OMA) was studied in the main transition and flow regions. Even though the aliphatic end groups of the side chain of HB and OMA are roughly the same, the T _g temperature of poly(HB) is ∼ 80 K higher than that of poly(OMA); this fact is due to the presence of the stiff phenyl benzoate mesogenic group in the side chain of HB. With increasing content of OMA in the copolymer the superimposed curves of the storage G′ _p and loss G′′ _p moduli at a constant temperature shift towards shorter frequencies. It has been shown that this shift is mainly due to an increase of the free volume in the copolymers with increasing content of OMA. While HB monomer shows liquid crystalline (LC) properties, its polymer (poly(HB)) and random copolymers with OMA show only isotropic thermal behaviour because no flexible spacer is present in the side chain of HB which would decouple the main chain and mesogenic group motions. This means that neither the homopolymer of HB, nor its copolymers with a flexible comonomer retain the LC properties of the starting LC monomer, HB. Received: 26 September 1996/Revised: 7 November 1996/Accepted: 7 November 1996     

<Emphasis Type="Italic">N</Emphasis>-Acylated Bacteriohopanehexol-Mannosamides from the Thermophilic Bacterium <Emphasis Type="Italic">Alicyclobacillus acidoterrestris</Emphasis>

Identification of molecular species of various N-acylated bacteriohopanehexol-mannosamides from the thermophilic bacterium Alicyclobacillus acidoterrestris by semipreparative HPLC and by RP-HPLC with ESI is described. We used triple-quadrupole type mass spectrometer, ¹H and ¹³C NMR for analyzing this complex lipid. CD spectra of two compounds (model compound—7-deoxy-d-glycero-d-allo-heptitol obtained by stereospecific synthesis, and an isolated derivative of hopane) were also measured and the absolute configuration of both compounds was determined. On the basis of all the above methods, we identified the full structure of a new class of bacteriohopanes, represented by various N-acylated bacteriohopanehexol-mannosamides.     

Attitude, knowledge, and skill competencies for practice in professional geropsychology: Implications for training and building a geropsychology workforce.

Professional geropsychology is a growing area of practice and training. To meet the mental health needs of an aging population, increasing numbers of psychologists need to develop competence to work with older adults, their families, and related care systems. The Pikes Peak model for geropsychology training (Knight, Karel, Hinrichsen, Qualls, & Duffy, 2009) delineates attitude, knowledge, and skill competencies for professional geropsychology practice and makes recommendations for training. In this paper, we define and illustrate the Pikes Peak geropsychology practice competencies through a case example. In the case, an older man with complex needs seeks care through a generalist psychologist in an outpatient setting. The attitudes, knowledge, and skills that the psychologist needs to consider, and implications for training, are reviewed. Training recommendations and resources are provided, with a focus on the training needs of psychologists who wish to expand their practices to include older adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A heuristic to manage perishable inventory with batch ordering,positive lead-times,and time-varying demand

So far the literature on inventory control for perishable products has mainly focused on (near-) optimal replenishment policies for a stylized environment, assuming no lead-time, no lot-sizing, stationary demand, a first in first out withdrawal policy and/or product life time equal to two periods. This literature has given fundamental insight in the behavior and the complexity of inventory systems for perishable products. In practice, many grocery retailers have recently automated the inventory replenishment for non-perishable products. They recognize they may need a different replenishment logic for perishable products, which takes into account e.g. the age of the inventory in the system. Due to new information technologies like RFID, it now also becomes more economically feasible to register this type of information. This paper suggests a replenishment policy for perishable products which takes into account the age of inventories and which requires only very simple calculations. It will be shown that in an environment, which contains important features of the real-life retail environment, this new policy leads to substantial cost reductions compared with a base policy that does not take into account the age of inventories.