Reliable Correlation (reliable + correlation)

Distribution by Scientific Domains


Selected Abstracts


Early Pragian conodont-based correlations between the Barrandian area and the Spanish Central Pyrenees

GEOLOGICAL JOURNAL, Issue 5 2007
Ladislav Slavík
Abstract Occurrences and distribution of extremely scarce eognathodontids do not facilitate reliable correlation across the European regions. The correlation of the traditional early Pragian of the Prague Synform (a part of the classical Barrandian area) and the Spanish Central Pyrenees (section Segre 1) is based on conodont taxa of the Icriodus steinachensis and the Pelekysgnathus serratus stocks. This correlation has the potential to be extended to other peri-Gondwanan regions where this scarcity of eognathodontid faunas exists as well. Application of the morphotype subdivision in I. steinachensis enables approximation of the beginning of the Pragian in the Pyrenees. It is based on the entry of I. steinachensis beta morphotype; it enters together with early eognathodontid taxa in the Barrandian sections. These correlations show that routine application of certain zonal concepts can lead to misleading conclusions. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Towards an isotopic ecology of herbivory in the Puna ecosystem: new results and patterns on Lama glama

INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 2 2009
H. D. Yacobaccio
Abstract We present stable isotopic data obtained in order to elucidate the diet of current domestic camelids and their feeding areas, as a necessary step for the interpretation of archaelogical assemblages, and to answer questions regarding past diet, herd structure, foraging zones and interaction with human populations. Seventeen new ,13C collagen isotope values from Lama glama bones were measured in order to start a systematic study of the isotopic ecology of herbivory in the Puna ecosystem of Jujuy province, Argentina. These values were compared with those previously available, and a reliable correlation between altitude and variation in isotopic values was found: of the order of ,2, depletion for each 500,m increase in altitude. These results were interpreted as related to variation in vegetal assemblage due to altitude. We consider that the outcomes of this research exceed the scope of our study area, being important to the Argentine Puna as a whole, and will also contribute to the development of current animal population ecological models applied to the interpretation of archaeological remains. Copyright © 2009 John Wiley & Sons, Ltd. [source]


The search for low energy conformational families of small peptides: Searching for active conformations of small peptides in the absence of a known receptor,

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 15 2007
Katrina W. Lexa
Abstract Breast cancer is the most common cancer among women. Tamoxifen is the preferred drug for estrogen receptor-positive breast cancer treatment, yet many of these cancers are intrinsically resistant to tamoxifen or acquire resistance during treatment. Therefore, scientists are searching for breast cancer drugs that have different molecular targets. Previous work revealed that 8-mer and cyclic 9-mer peptides inhibit breast cancer in mouse and rat model systems, interacting with an unknown receptor, while peptides smaller than eight amino acids did not inhibit breast cancer. We have shown that the use of replica exchange molecular dynamics predicts structure and dynamics of active peptides, leading to the discovery of smaller peptides with full biological activity. These simulations identified smaller peptide analogs with a conserved turn, a ,-turn formed in the larger peptides. These analogs inhibit estrogen-dependent cell growth in a mouse uterine growth assay, a test showing reliable correlation with human breast cancer inhibition. We outline the computational methods that were tried and used with the experimental information that led to the successful completion of this research. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 [source]


Fallacies in probability judgments for conjunctions and disjunctions of everyday events

JOURNAL OF BEHAVIORAL DECISION MAKING, Issue 3 2009
Fintan J. CostelloArticle first published online: 16 OCT 200
Abstract The conjunction fallacy occurs when people judge a conjunction B-and-A as more probable than a constituent B, contrary to probability theory's ,conjunction rule' that a conjunction cannot be more probable than either constituent. Many studies have demonstrated this fallacy in people's reasoning about various experimental materials. Gigerenzer objects that from a ,frequentist' standpoint probability theory is not valid for these materials, and so failure to follow the conjunction rule is not a fallacy. This paper describes three experiments showing that the conjunction fallacy occurs as consistently for conjunctions where frequentist probability theory is valid (conjunctions of everyday weather events) as for other conjunctions. These experiments also demonstrate a reliable correlation between the occurrence of the conjunction fallacy and the disjunction fallacy (which arises when a disjunction B-or-A is judged less probable than a constituent B). This supports a probability theory,+,random variation account of probabilistic reasoning. Copyright © 2008 John Wiley & Sons, Ltd. [source]


L-type amino-acid transporter 1 as a novel biomarker for high-grade malignancy in prostate cancer

PATHOLOGY INTERNATIONAL, Issue 1 2009
Takeshi Sakata
To find reliable biomarkers for high-grade malignancy, the relationship between immunohistochemical L-type amino-acid transporter 1 (LAT1) expression of biopsy samples, determined with the newly developed monoclonal antibody against human LAT1, and prognosis of patients with prostate cancer, was investigated. The intensity and score of immunohistochemical LAT1 expression of first biopsy samples were assessed using the modified Sinicrope et al. method and were found to be correlated with poor survival for the study group of 114 surgically treated patients as a whole (P = 0.0002 and 0.0270, respectively). LAT1 intensity further had a significant relationship (P = 0.0057) with prognosis in pathological T3 + T4 groups. Multivariate analysis indicated that the LAT1 intensity and score were more reliable prognostic markers, compared with the Gleason score and the Ki-67 labeling index. A relationship of the LAT1 intensity and score with prognosis could also be confirmed in 63 patients with inoperable cancer (P = 0.0070 and <0.0001, respectively). Similarly, significant differences in prognosis were confirmed in clinical T3 + T4 groups (P = 0.0091 and 0.0244, respectively). Moreover, the combination of LAT1 expression and Gleason score was found to have a more reliable correlation with prognosis. Thus, elevated LAT1 expression in prostate cancers is a novel independent biomarker of high-grade malignancy, which can be utilized together with the Gleason score, which is mainly dependent on cellular and structural atypia, to assess prognosis. [source]


Bhutani-based nomograms for the prediction of significant hyperbilirubinaemia using transcutaneous measurements of bilirubin

ACTA PAEDIATRICA, Issue 12 2009
YA Bental
Abstract Aim:, Prospectively establish the relationship between transcutaneous bilirubin (TcB) and total serum bilirubin (TSB), and develop nomograms similar to Bhutani's nomograms, based on our TcB data. Methods:, Our study sample was from a total population of 1069 infants, near term and term healthy newborns, admitted during 2.5 month period of the study. TSB was performed on all infants who were felt to be clinically jaundiced. Before obtaining the TSB, a TcB was performed (Jaundice Meter Minolta/Draeger JM-103). Measurements were performed on two sites: forehead and mid-sternum, and the mean of both measurements was calculated. Results:, A total of 1091 paired measurements were obtained from 628 infants. Linear regression showed a significant relation between TSB and TcB (R2 of 0.846). In multiple regression analysis, all independent variables studied, i.e. gestational age (or birthweight), age at sampling and ethnicity had a negligible influence on the relationship. We subsequently developed our local-nomograms of hour-specific mean TcB with 40, 75 and 95 percentile lines. Conclusions:, In our local settings and population, we found a reliable correlation between laboratory measurements of TSB and TcB. We were able to develop our local-Bhutani-based TcB nomograms for screening babies during hospital stay and pre-discharge for assessing the risk of hyperbilirubinaemia. [source]


A preliminary prediction of seismic damage-based degradation in RC structures

EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 7 2001
Vinay K. Gupta
Abstract Estimation of structural damage from a known increase in the fundamental period of a structure after an earthquake or prediction of degradation of stiffness and strength for a known damage requires reliable correlations between these response functionals. This study proposes a modified Clough,Johnston single-degree-of-freedom oscillator to establish these correlations in the case of a simple elasto-plastic oscillator. It is assumed that the proposed oscillator closely models the response of a given multi-degree-of-freedom system in its fundamental mode throughout the duration of the excitation. The proposed model considers the yield displacement level and ductility supply ratio-related parameter as two input parameters which must be estimated over a narrow range of ductility supply ratio from a frequency degradation curve. This curve is to be identified from a set of recorded excitation and response time-histories. Useful correlations of strength and stiffness degradation with damage have been obtained wherein a simple damage index based on maximum and yield displacements and ductility supply ratio has been considered. As an application, the proposed model has been used to demonstrate that ignoring the effects of aftershocks in the case of impulsive ground motions may lead to unsafe designs. Copyright © 2001 John Wiley & Sons, Ltd. [source]


Improvement of the basic correlating equations and transition criteria of natural convection heat transfer

HEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 4 2001
Shi-Ming Yang
Abstract In this paper, improvements in the basic physical laws of natural convection heat transfer were implemented in two major respects by incorporating recent research findings in this field. A preferred transition criterion was adopted in this paper to correlate all of the experimental data. Since transition correlations are primarily flow stability problems, the Grashof number, instead of the Rayleigh number, was found to be the preferred criterion. Furthermore, in the case of natural convection heat transfer from a horizontal cylinder, a series of experimental data in the high-Rayleigh-number regions recently became available. These data made it possible to establish new reliable correlations and also to test the validity of previous correlations. It is concluded that the previous correlation for a horizontal cylinder in high-Rayleigh-number regions was based on unreliable experimental results. The transition correlation for a horizontal cylinder occurred at much higher values of Rayleigh number than the previous recommendation. In the case of natural convection heat transfer from a vertical plate, more accurate property values for air under pressurized conditions are now available. This made it possible to replot the reliable data of Saunders. From this result and the experimental result of Warner and Arpaci, a new set of basic correlations in natural convection heat transfer for laminar, transitional, and turbulent regimes are recommended. These recommendations reflect a better understanding of the basic physical laws in the field of heat convection. © 2001 Scripta Technica, Heat Trans Asian Res, 30(4): 293,300, 2001 [source]


The design of duct venting of gas explosions

PROCESS SAFETY PROGRESS, Issue 2 2008
Almerinda Di Benedetto
Abstract Venting systems are useful for the mitigation of accidental explosions. Vent ducts should be used if equipment is located indoors, as NFPA 68 (2007) suggests, for discharging combustion products to safe location. However, the presence of a duct is likely to increase the severity of the explosion with respect to simply vented vessels. Up to now, no reliable correlations are available for the sizing of ducted vented systems. The only correlation available was developed by Bartknecht in 1993 for gas explosion, also acknowledged by NFPA 68. In this study, we propose an engineering correlation based on semi-empirical engineering methodologies, which is able to quantify the relations between geometric properties and the peak pressure occurring in the combustion chamber in the presence of a duct fitted on the vent panel. To this aim, we have regressed all the available experimental data on gas explosion in ducted-vented vessels. © 2007 American Institute of Chemical Engineers Process Saf Prog, 2008 [source]