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The work compatibility modelis a multidimensional diagnostic tool of human performance that measures the level of synchronization between the workforce and the work environment. The authors propose a quantitative model and a graphic‐based framework to implement the work compatibility model at the operational level. Using the proposed approach, managers can identify smart solutions that contribute to personnel development. The model is tested with data collected from a manufacturing company to analyze the behavior of the proposed indices. The implementation is exemplified by a case study. The work compatibility model is a forward‐looking approach to hidden aspects and potential deficiencies of the organization. Decision makers can provide targeted solutions to low‐performing elements of the work environment that are discovered through this tool. © 2006 Wiley Periodicals, Inc. Hum Factors Man 16: 133–153, 2006.

In this paper, we have investigated the lower critical solution temperature (LCST) of N-isopropylacrylamide–acrylic acid (NIPAAm-AAc) copolymer as a function of chain-transfer agent/initiator mole ratio, acrylic acid content of copolymer, concentration, pH and ionic strength of aqueous copolymer solution. Aqueous solutions with the desired properties were prepared from previously purified polymers, synthesized at 65 °C by solution polymerization using ethanol. The effects of each parameter on the LCST were examined experimentally.In addition, an artificial neural network model that is able to predict the lower cretical solution temperature was develeped. The predictions from this model compare well against both training and test data sets with an average error less than 2.53%. Figure Cross plot of predicted and experimental LCST values for the testing data set.

Lean production represents a change in production system paradigm that calls for integration of the human and technological practices. This article reviews previous models of lean production that concentrated mainly on some distinct features of its philosophy, organization, and techniques and presents a framework of lean production as a sociotechnological system. The proposed framework provides an integrated view based on the interactions of human and technological elements. The lean enterprise is viewed as a dynamic process that translates its goals (zero waste, flow, and pull) into combined techniques that should be implemented throughout the entire organization. © 2004 Wiley Periodicals, Inc. Hum Factors Man 14: 285–306, 2004.

A random copolymer of N-isopropyl acrylamide (NIPAAm) and acrylic acid (AAc) with an AAc content of 3.1 ± 0.19 mmol of carboxylic acid groups per gram of the copolymer and with a number-average molecular weight of 1400 was synthesized by free-radical polymerization with 2,2'-azoisobutyronitrile in dimethylformamide. Then, monopeptide, dipeptide, and tripeptide (i.e., alanine) conjugates of this copolymer were prepared with their carboxyl-end-protected (with methyl ester hydrochloride) form of alanine, with a water-soluble carbodiimide. Of the carboxylic acids, 93, 69, and 57% were conjugated (loaded) with alanine at the monopeptide, dipeptide, and tripeptide conjugation steps, respectively. The chemical structures of the copolymer and conjugates were analyzed by Fourier transform infrared and ¹H-NMR, which revealed the conjugate formation. Amino acid conjugation caused significant decreases in the lower critical solution temperatures (LCST) of the copolymer, especially at pH 7.4. The LCST values of the dipeptide and tripeptide conjugates of poly(NIPAAm-co-AAc) at both pH 4.0 and 7.4 shifted to significantly higher temperatures. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2012–2019, 2003

Catalase was entrapped in thermally reversible poly(isopropylacrylamide‐co‐hydroxyethylmethacrylate) (pNIPAM/HEMA) copolymer hydrogels. The thermoresponsive hydrogels, in cylindrical geometry, were prepared in an aqueous buffer by redox polymerization. It was observed that upon entrapment, the activity retention of catalase was decreased between 47 and 14%, and that increasing the catalase loading of hydrogel adversely affected the activity. The kinetic behaviour of the entrapped enzyme was investigated in a batch reactor. The apparent kinetic constant of the entrapped enzyme was determined by the application of Michaelis–Menten model and indicated that the overall reaction rate was controlled by the substrate diffusion rate through the hydrogel matrix. Due to the thermoresponsive character of the hydrogel matrix, the maximum activity was achieved at 25 °C with the immobilized enzyme. The Km value for immobilized catalase (28.6 mM) was higher than that of free enzyme (16.5 mM). Optimum pH was the same for both free and immobilized enzyme. Operational, thermal and storage stabilities of the enzyme were found to increase with immobilization.© 1999 Society of Chemical Industry

99Tcm-latex particles (LP) is a newly developed radiopharmaceutical for the evaluation of the gastrointestinal (GI) tract. Following oral ingestion, it passes through the entire GI tract undissolved. The purpose of the present investigation was to introduce the clinical application of 99Tcm-LP. A group of 11 healthy volunteers was studied. Following a 12 h fast, the subjects were given 150 ml of water containing 37 MBq of 99Tcm-LP orally. Dynamic images up to 2 h were recorded to document temporal progression of radioactivity. Static images of the abdomen and whole body were taken at intervals. In normal subjects the tracer arrival times at the caecum and sigmoid colon were 3.2±0.9 and 11.2±3.2 h, respectively. The average t1/2value for gastric emptying, 50 colonie filling and small bowel transit time were found to be 21.6±5.6, 233±72 and 211±66.4 min, respectively. In conclusion, 99Tcm-LP has the potential of providing functional information of the GI tract.

Latex particles coated with either amino or carboxyl groups were labelled with 99mTc. Two labelling methods were used: (1) direct labelling with tin reduction and (2) ligand exchange with tin pyrophosphate. Labelling efficiency and the radiochemical impurities were determined by thin-layer chromatography. Effect of [Sn2+] and pH on labelling yield was investigated to find the optimum labelling conditions. 99mTc-labelled latexes were administered orally to six normal subjects, and scintigrams from the abdomen were obtained at 1, 3, 6, and 24h. Whole-body scintigrams were also taken by a gamma-camera. The first method was found to be efficient for carboxyl coated latexes and the second method for both types, giving > 98 per cent labelling efficiency. Labelled latexes were stable up to 24 h of testing at RT (> 99 per cent labelled). Scintigraphic studies showed that the labelled particles remained in GIT (98·11 ± 0·92 per cent at 6 h) without dissociation of the label. No radioactivity was observed in the thyroid, stomach (at late images) and urinary bladder. This study demonstrated that latex particles coated with either amino or carboxyl groups can be efficiently labelled with 99mTc and used in the studies of GI function.

Abstract: Twenty six trace elements were determined by INAA in the aerosol samples collected at two stations in Ankara, Turkey. Industrially derived elements, Se, As, Sb, Zn and Au did not show seasonal dependence and they were not substantially enriched. Elements originating from coal combustion are highly enriched and have higher concentrations in the winter. Correlation factors indicate that motor vehicles, coal and oil combustion are the main sources of aerosols over the city.

Abstract: Multielement study of fog water at the Uludag mountain, Northwestern Turkey, is presented. Fourteen elements (Al, As, Br, Cl, Cs, Fe, I, K, Mn, Na, Sc, Sb, V, Zn) are determined by INAA. Sulfate is determined by ion chromatography. Sulfate showed good correlation with non-crustal Mn. Marine particles dominated fog water composition among four major sources. Low to moderate variations of trace element concentration were observed by using three different fog collectors.

Kinetics of non-catalytic liquefaction of Seyitomsr lignite has been investigated under hydrogen pressure, using tetralin as a Bolvent in a laboratory Bcale batch autoclave reactor.In the first set of experiment hydrogen initial pressure and reaction temperature were kept constant, the reaction time and coal/aolvent ratio were changed at five and three levels espectively. In the second set of experiments coal/solvent ratio was kept constant and hydrogen initial pressure, reaction temperature and time were individually changed at four levels. The produot was analyzed in terms of total conversion, liquid yield and liquid product distribution determined as preasphaltenes, asphaltense and oila. A satisfactory correlation was obtained using the kinetic model proposed by Shalabi et al (1979).

Sampling and analyses of snow water at a mountainous site of northwestern Turkey were described. A snow sampler designed in our laboratory was used in the sampling. Ion chromatography, flame atomic absorption and emission spectrophotometry were very good techniques for the determinations of major ions in snow samples. The accuracy of results was tested by using different standard reference materials for both techniques. The results were in good agreement with the certified concentrations. The results of analyses were accepted if the error was less than 15%. The overall precision was in between 1-6%. The concentrations of snow samples were high compared with the literature values. The pH of them was found to be acidic with the average value of 4.3. Magnesium had the highest average scavenging ratio, and ammonium ion had the lowest average scavenging ratio. Sodium, K, Ca and Mg were mostly originated from the earth crust. Marine contribution to the sampling site was also effective.

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