Panel performance: Modelling variation in sensory profiling data by multiway analysis

Sensory profiling data is essentially three-way data where samples, attributes and assessors are the three dimensions of information. It is common practice to average over the assessors and focus the analysis on the relations between samples and sensory descriptors. However, since assessor reliability can not be controlled in advance, posthoc analysis on assessors is needed to assess performance of the individual and at the panel level. For this purpose, multiway analysis is a very efficient data method as it provides information on samples, attributes and assessors, simultaneously [1]. PARAllel FACtor (PARAFAC) analysis is one of the most used multiway methods in sensory analysis [2][3]. It is based on two basic assumptions: 1) there exist latent variables behind the identified sensory descriptors describing the variation among the products; 2) assessors have different sensitivities to these common latent variables. However, assessors may perceive the factors differently, so the assumption of “common latent variables” becomes questionable. This may happen when the panel is not well trained and/or the samples present subtle differences difficult to detect. In this work a more flexible approach to the analysis of sensory data is presented. Specifically, the work proposes to use PARAFAC2 modelling [4] as it allows each assessor to have an individual idiosyncratic perceptive model. The data was obtained from a descriptive sensory analysis of organic milk samples. Results show that PARAFAC2 is very useful to highlight disagreement in the panel on specific attributes and to detect outlying assessors. In addition, by using PARAFAC2 an improvement in the description of samples is also achieved. On the other hand, PARAFAC has to be preferred to PARAFAC2 when a good panel agreement is observed, since it provides more stable solutions and no further gain in information is obtained from PARAFAC2. Finally, the work proposes an index to measure the performance of each assessor based on individual sensitivity and reproducibility

Sensory milk properties at the farm level – the terroir dimension

In recent years, the Danish milk market has shown an increase in the consumption of organic milk as well as a growing variety of milk with specific features including farm milk. The production of milk from a single farm and pasture-based (PB) feeding regimes is of special interest as it implies a “sense of place” or terroir. The PB feeding regimes vary with season and might also vary on a day-to-day basis. It is therefore important to understand the impact of the feed on the sensory properties of the milk [1]. This study aims at demonstrating how analytical sensory analysis can provide important information about the influence of breed, season and variation in farm management from PB feeding regimes on the sensory properties of organic farm milk. The study was performed in 2007 and 2008 during two seasons (spring/autumn) representing 28 milk samples from 7 organic farms with either Holstein or Jersey cows. PB feeding regimes were based on pastures with varying amounts of white clover together with perennial ryegrass and supplement feeding with silage and concentrates. Significant results were found for season and breed with a larger variation in sensory flavour properties of spring milk and milk from Holstein cows. In general, there was a tendency of the milk being characterized as having a ‘greener’ odour, ‘sweet’ and ‘maize-like’ flavour in spring and a more ‘bitter’ taste in the autumn. The results show a distinct relation between sensory milk properties and the amount of pasture in the ration and white clover in the pasture. Relations to other production conditions such as composition of the supplement feed also tended to have an impact on the sensory characteristics of the milk. It is thus concluded, that a sensory analytical tool can provide important information about the sensory properties of organic farm milk, reflecting time and place. Seasonal variations appear to be an important factor in the terroir dimension of milk and may be more actively used in relation to communication of the sensory properties to the consumer

Monitoring panel performance within and between sensory experiments by multi-way analysis

In sensory analysis a panel of trained assessors evaluates a set of samples according to specific sensory descriptors. The training improves objectivity and reliability of assessments. However, there can be individual differences between assessors left after the training that should be taken into account in the analysis. Monitoring panel performance is then crucial for optimal sensory evaluations. The quality of the results is strongly dependent on the performance of each assessor and of the panel as a whole. The present work proposes to analyze the panel performance within single sensory evaluations and between consecutive evaluations. The basic idea is to use multi-way models to handle the three-way nature of the sensory data. Specifically, a PARAFAC model is used to investigate the panel performance in the single experiment. N-PLS model is used to test the predictive ability of the panel on each experiment. A PARAFAC model is also used for monitoring panel performance over different experiments

Patient perceptions of physician empathy, satisfaction with physician, interpersonal trust, and compliance

Objectives: This study was designed to investigate psychometric properties of the Jefferson Scale of Patient Perceptions of Physician Empathy (JSPPPE), and to examine correlations between its scores and measures of overall satisfaction with physicians, personal trust, and indicators of patient compliance. Methods: Research participants included 535 out-patients (between 18-75 years old, 66% female). A survey was mailed to participants which included the JSPPPE (5-item), a scale for measuring overall satisfaction with the primary care physician (10-item), and demographic questions. Patients were also asked about compliance with their physician\u27s recommendation for preventive tests (colonoscopy, mammogram, and PSA for age and gender appropriate patients). Results: Factor analysis of the JSPPPE resulted in one prominent component. Corrected item-total score correlations ranged from .88 to .94. Correlation between scores of the JSPPPE and scores on the patient satisfaction scale was 0.93. Scores of the JSPPPE were highly correlated with measures of physician-patient trust (r \u3e.73). Higher scores of the JSPPPE were significantly associated with physicians\u27 recommendations for preventive tests (colonoscopy, mammogram, and PSA) and with compliance rates which were \u3e .80). Cronbach\u27s coefficient alpha for the JSPPPE ranged from .97 to .99 for the total sample and for patients in different gender and age groups. Conclusions: Empirical evidence supported the psychometrics of the JSPPPE, and confirmed significant links with patients\u27 satisfaction with their physicians, interpersonal trust, and compliance with physicians\u27 recommendations. Availability of this psychometrically sound instrument will facilitate empirical research on empathy in patient care in different countries

Cosmogenic-neutron activation of TeO2 and implications for neutrinoless double-beta decay experiments

Flux-averaged cross sections for cosmogenic-neutron activation of natural tellurium were measured using a neutron beam containing neutrons of kinetic energies up to $\sim$800 MeV, and having an energy spectrum similar to that of cosmic-ray neutrons at sea-level. Analysis of the radioisotopes produced reveals that 110mAg will be a dominant contributor to the cosmogenic-activation background in experiments searching for neutrinoless double-beta decay of 130Te, such as CUORE and SNO+. An estimate of the cosmogenic-activation background in the CUORE experiment has been obtained using the results of this measurement and cross-section measurements of proton activation of tellurium. Additionally, the measured cross sections in this work are also compared with results from semi-empirical cross-section calculations.Comment: 11 pages, 5 figure

Differential cross section for neutron-proton bremsstrahlung

The neutron-proton bremsstrahlung process $(np \to np\gamma)$ is known to be sensitive to meson exchange currents in the nucleon-nucleon interaction. The triply differential cross section for this reaction has been measured for the first time at the Los Alamos Neutron Science Center, using an intense, pulsed beam of up to 700 MeV neutrons to bombard a liquid hydrogen target. Scattered neutrons were observed at six angles between 12$^\circ$ and 32$^\circ$, and the recoil protons were observed in coincidence at 12$^\circ$, 20$^\circ$, and 28$^\circ$ on the opposite side of the beam. Measurement of the neutron and proton energies at known angles allows full kinematic reconstruction of each event. The data are compared with predictions of two theoretical calculations, based on relativistic soft-photon and non-relativistic potential models.Comment: 5 pages, 3 figure

Components of metabolic syndrome in the first trimester of pregnancy as predictors of adverse perinatal outcome

Objectives: It is the prospective observational study aimed at early prediction of pregnancy complications in women with symptoms of MS. Material and methods: 124 Caucasian women in singleton pregnancies 11th to the 13th wks 6 days of gestation with MS criteria compared to 30 healthy controls. Perinatal maternal and fetal results were analyzed. Results: Increased in the MS group were: age (32.9 y vs. 28.6 y; p = 0,00), weight 11 to 13 + 6 weeks of gestation (79.0 kg vs. 59.7 kg; p = 0.00), BMI (29 kg/m2 vs. 21.6 kg/m2; p = 0.00), waist–hip ratio (WHR) (0.9 vs. 0.8; p = 0.00). Maternal serum parameters were higher in the MS group: LDL-cholesterol (124.1 vs. 109.6 mg/dL; p = 0.02), t-PA (2556.8 vs. 1949.5 pg/mL; p < 0.00), GGTP (16.8 vs. 13.3 IU/L; p = 0.02) and lower values for: adiponectin (6.4 vs. 7.5 μg/mL; p = 0.01), SHBG (273.4 vs. 338.4 nmol/L; p = 0.001). MS group neonates higher body weight (3594.4 vs. 3312.2 g; p = 0.01), significantly frequent macrosomic neo­nates (> 4000 g) (20.9% vs. 6.6%; p = 0.042), GDM (12% vs. 0; p = 0.019). Conclusions: Higher E-selectin serum concentration, GGTP and lower SHBG in first trimester are additionally to fasting maternal glucose, higher BMI and maternal age predictive for GDM. Higher E-selectin, fasting glucose, increased BMI and lower adiponectin serum concentration in first trimester are significant predictors of fetal macrosomia. Maternal BMI > 24.5 kg/m2 is the best predictor of increased risk of fetal macrosomia and gestational diabetes mellitus

Highly efficient synthesis of the tricyclic core of Taxol by cascade metathesis

An efficient enantioselective synthesis of the ABC tricyclic core of the anticancer drug Taxol is reported. The key step of this synthesis is a cascade metathesis reaction, which leads in one operation to the required tricycle if appropriate fine-tuning of the dienyne precursor is performed