Reproducibility of the Italian ISQ method for quality classification of bread wheats: An evaluation by expert assessors

The great variety of different bakery products in Italy has led to the development of a method, the Synthetic Index of Quality (Indice Sintetico di Qualità, ISQ), for the classification of bread wheats in different quality categories. Based on chemical and rheological properties, each wheat sample is assigned to the most suitable class by an expert assessor. In many cases this procedure is not straightforward, making the class assignation uncertain, thus leading to the possibility of controversies during the trading phase. In the present study, in order to have a quantitative estimate of the validity and reliability of this procedure, a panel composed of nine expert assessors was utilised for the repeated evaluation of 100 samples of bread wheats of various qualities. The results suggest that the proposed approach can be used both to monitor the reliability of the single assessors, and to identify samples whose class assignation is reasonably indubitable, e.g. to be used for the development of automated classification methods. Moreover, the analysis of the most uncertain assignation cases can be useful in order to enhance the ISQ classification method itself. Copyright © 2007 Society of Chemical Industry     

ORION — Ontology-based queRy routIng in Overlay Networks

Current search engines are rapidly changing to embrace more powerful mechanisms that are capable of reasoning on semantic attributes of contents in a distributed repository. Formalisms have been proposed to represent the semantic attributes. Yet, traditional approaches for content sharing in peer-to-peer systems cannot be adapted to use semantic information. Some novel proposals in the literature consider semantic aspects in P2P systems. However, they either make strong assumptions on the semantic model, or have high communication and computation overhead.     

Accurate pHEMT nonlinear modeling in the presence of low-frequency dispersive effects

Low-frequency (LF) dispersive phenomena due to device self-heating and/or the presence of "traps" (i.e., surface state densities and bulk spurious energy levels) must be taken into account in the large-signal dynamic modeling of III-V field-effect transistors when accurate performance predictions are pursued, since these effects cause important deviations between direct current (dc) and dynamic drain current characteristics. In this paper, a new model for the accurate characterization of these phenomena above their cutoff frequencies is presented, which is able to fully exploit, in the identification phase, large-signal current-voltage (I-V) measurements carried out under quasi-sinusoidal regime using a recently proposed setup. Detailed experimental results for model validation under LF small- and large-signal operating conditions are provided. Furthermore, the I-V model proposed has been embedded into a microwave large-signal pseudomorphic high electron-mobility transistor (pHEMT) model in order to point out the strong influence of LF modeling on the degree of accuracy achievable under millimeter-wave nonlinear operation. Large-signal experimental validation at microwave frequencies is provided for the model proposed, by showing the excellent intermodulation distortion (IMD) predictions obtained with different loads despite the very low power level of IMD products involved. Details on the millimeter-wave IMD measurement setup are also provided. Finally, IMD measurements and simulations on a Ka-band highly linear power amplifier, designed by Ericsson using the Triquint GaAs 0.25-/spl mu/m pHEMT process, are shown for further model validation.     

Relationship between repeated measures of hemodynamics, muscle sympathetic nerve activity, and their spectral oscillations

BACKGROUND: We determined the intraclass correlation coefficients (ICC) of repeated measures of the mean levels and variability of RR and muscle sympathetic nerve activity (MSNA) in 7 normal subjects. We examined whether spontaneous fluctuations in RR and MSNA over repeated measurements were mirrored by changes in spectral components of RR and MSNA. METHODS AND RESULTS: Twenty-minute recordings of respiration, RR, blood pressure (BP), and MSNA were performed at day 1, 1 week, 1 month, and 3 months and divided into two 10-minute periods for the analysis of short-term reliability. Comparison between these recordings also determined the long-term reliability. Linear regressions examined the relationship between changes in these measurements and changes in spectral components of RR and MSNA. All analyses were carried out blinded to subject and session. Short-term ICC of RR, BP, MSNA and of the variabilities of RR and MSNA (in % of total power) ranged between .98 and .70 and indicated a good short-term reliability. The long-term reliability of RR variability was comparable to MSNA variability (range of ICC, .34 to .52). Spontaneous decreases in RR during the repeated recordings were accompanied by increases in sympathetic drive, as evidenced by increases in the ratio of low-frequency to high-frequency variability (LF/HF ratio) of RR interval (r=-.43, P<.01) and by increases in MSNA (r= -.36, P=.01). The changes in the LF/HF ratio of RR were mirrored by parallel changes in the LF/HF ratio of MSNA (r=+.30, P<.05). Spontaneous decreases in BP were accompanied by increases in the LF/HF ratio of MSNA (r=-.52; P=.0001). CONCLUSIONS: Heart rate, MSNA, and their variability are stable in the short-term, but less so over the long term. Spontaneous changes in repeated measurements of RR interval and blood pressure over the long term are accompanied by parallel changes in the normalized spectral components of RR and MSNA variability. Thus even over an extended period, there is a synchrony between changes in absolute cardiovascular measures and changes in their spectral components.     

Evidence that elongation of the catalytic loop of the Azotobacter vinelandii rhodanese changed selectivity from sulfur- to phosphate-containing substrates

Recent investigations have shown that the rhodanese domains,ubiquitous structural modules which might represent an exampleof conserved structures with possible functional diversity,are structurally related to the catalytic subunit of Cdc25 phosphataseenzymes. The major difference characterizing the active-siteof the Azotobacter vinelandii rhodanese RhdA, with respect tothe closely related Cdc25s (A, B, C), is that in Cdc25 phosphatasesthe active site loop [His–Cys–(X)₅–Arg] isone residue longer than in RhdA [His–Cys–(X)₄–Arg].According to the hypothesis that the length of the RhdA active-siteloop should play a key role in substrate recognition and catalyticactivity, RhdA scaffold was the starting point for producingmutants with single-residue insertion to generate the catalyticloop HCQTHAHR (in RhdA-Ala) and HCQTHSHR (in RhdA-Ser). Analysesof the catalytic performances of the engineered RhdAs revealedthat elongation of the catalytic loop definitely compromisedthe ability to catalyze sulfur transfer reactions, while itgenerated ‘phosphatase’ enzymes able to interactproductively with the artificial substrate 3-O-methylfluoresceinphosphate. Although this study is restricted to an example ofrhodanese modules (RhdA), it provided experimental evidenceof the hypothesis that a specific mutational event (a single-residueinsertion or deletion in the active-site loop) could changethe selectivity from sulfur- to phosphate-containing substrates(or vice versa). Received February 17, 2003; revised May 30, 2003; accepted June 6, 2003.     

Extended-spectrum beta-lactamases from Klebsiella pneumoniae strains isolated at an Italian hospital

Eighteen strains of Klebsiella pneumoniae recently isolated from hospitalized patients were resistant or moderately resistant to oxyimino-cephalosporins (ceftazidime and/or cefotaxime), aztreonam, cefoxitin and all but one were susceptible to imipenem. Analysis of enzymes produced by these clinical isolates revealed a wide pattern of extended-spectrum beta-lactamases. All isolates produced one or more beta-lactamases that were characterized preliminarily by their isoelectric point. Strains isolated early were from patients in the Intensive Care Unit and produced an ES beta-lactamase with an apparent pI of 7.6, whereas the later isolates were from surgical and medical wards of the same hospital and produced ES beta-lactamases with apparent pI of 8.2 and 8.4, respectively. This suggests the emergence of SHV-5 and MIR-1 beta-lactamases in our hospital. Agarose gel electrophoresis of plasmid DNA revealed the presence of a similar plasmid of approximate size 60 Kb in all isolates.     

Informed consent for phase I studies: evaluation of quantity and quality of information provided to patients

BACKGROUND: The process by which patients are informed and their consent is obtained in phase I trials has thus far been only marginally studied. Since 1986 we have followed an oral procedure, consisting of three consecutive conversations in which the investigator responsible for phase I studies, the research nurse and the patients' relatives and/or friends also participate, followed by the patients signing of a written consent form. It is required that six items of information considered essential by our staff be conveyed to patients by the responsible investigator. Meerwein's model, which defines three main dimensions of the informing process (the information itself, the emotional and interactive aspects), has been studied to ascertain whether it can be applied to evaluate the quality of the information proffered. METHODS: Thirty-two conversations were taped, transcribed and evaluated by one psychiatrist and one psychologist. A quantitative analysis of information was performed by calculating the number of patients to whom the essential items of information had been conveyed. The qualitative analysis was performed by rating on a five-point scoring system, from 1 (very bad) to 5 (excellent), the three dimensions of the informing process for each patient and by calculating for each dimension the mean score of the constituent items. RESULTS: Complete information about the characteristics of the phase I drug and the modalities of the treatment and follow up was given to almost 80% of the patients. All but one of the items of the information dimension scored 3.5 or higher, with the one related to the assessment by the doctor of the patient's understanding at the end of the consultation scoring less than 3 in 53% of the patients. All items of the emotional dimension scored higher than 3.5. Greater difficulty was encountered by the physician with the interactive dimension, the lowest mean scores being reported on the items related to the doctor's awareness of the indirectly expressed anxieties of the patients. In 71% of the consultations the three dimensions of information scored more than 3 and balanced one another, indicating a successful consultation by the Meerwein model. CONCLUSIONS: The informed consent procedure applied was satisfactory from a quantitative point of view, and the main items of information were acceptable to the patients. Meerweins's model proved to be applicable and useful for identifying pitfalls in communication. Greater attention should be paid to the indirect messages and implied criticisms of the patients to improve their participation in decision making. Physicians should become more skillful in providing adequate information and improve their methods of communication.     

Quality characteristics of dried pasta enriched with buckwheat flour

The addition of pseudocereal flours to semolina is becoming more and more popular to improve the nutritional quality of the resultant pasta. The aim of this study was the evaluation of several properties of commercial pasta made from a mixture of buckwheat flour and durum wheat semolina. The characterisation of products, belonging to different producers, focused on the evaluation of chemical and physical properties, such as water uptake and mechanical properties before and after cooking and surface characteristics. A sensory analysis was also performed in order to evaluate firmness, resistance to breaking and overall acceptability. The results highlighted high heterogeneity of the mechanical properties, solid loss and water absorption among the samples. The great variability could be explained by the different processing conditions adopted by each producer, particularly by the procedure used to form and shape the dough into the final product.