bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of variation in maternal carotenoid intake during gestation on offspring innate immune response in a matrotrophic viviparous reptile
Authors: Itonaga Keisuke , Jones Susan M. , Wapstra Erik
Published: August 2011

1. The evolution of matrotrophy may be related to high resource availability during gestation and consequently increased opportunity for reproductive investment via the placenta. Thus, matrotrophic species have smaller yolk volume than lecithotrophic species. Innate immune response of offspring at birth, which is important in protection against disease and parasites, may be influenced by the degree of reproductive investment of carotenoids, such as β‐carotene. However, to date, no study has investigated the effects of maternal carotenoid intake during reproduction on the innate immune responses of offspring in reptiles.

2. Some matrotrophic viviparous (live‐bearing) reptiles provide significant support for embryogenesis through both yolk and placenta. These species are excellent models for research into the evolutionary transitions from lecithotrophic reproduction (i.e. supply of resources from the yolks, e.g. birds) to highly matrotrophic reproduction (i.e. direct supply of most resources from the mother, e.g. mammals).

3. We used high‐performance liquid chromatography (HPLC) to examine carotenoid concentration in newly ovulated eggs of a matrotrophic viviparous lizard (Pseudemoia entrecasteauxii). Most eggs did not contain any carotenoids, including β‐carotene.

4. We then experimentally manipulated maternal β‐carotene availability (i.e. supplementation of β‐carotene in the diet or no supplementation) during gestation and investigated innate immune response of offspring (i.e. tissue swelling and proportion of monocytes in response to antigenic stimulation) at 2 days after birth. Subsequently, we investigated the effects of post‐natal β‐carotene intake on innate immune response of offspring using reciprocal transplant experiments in which we manipulated offspring β‐carotene availability for 2 weeks after birth. This experimental design also allowed us to assess the persistence of effects of maternal β‐carotene effects on innate immune response in offspring. We found that the immune response as measured by the proportion of monocytes was enhanced by high maternal β‐carotene intake during gestation, and this effect persisted for 2 weeks after birth. Furthermore, post‐natal β‐carotene intake enhanced innate immune response.

5. The maternally transferred ß‐carotene via the placenta during embryogenesis may be an important physiological adaptation to counter the costs of a reduction in organic substances supplied in the yolk that occurs as matrotrophy evolves.
Predicting strong community impacts using experimental estimates of per capita interaction strength: benthic herbivores and giant kelp recruitment
Authors: Sala Enric , Dayton Paul K.
Published: August 2011

The estimation of the strength of the interaction between species is key for understanding the organization of ecological communities. Although experimental and observational studies have estimated per capita interaction strength for individual consumers, no previous study has used such estimates for predicting the impact of a community of consumers on their prey in the field. Here we evaluate experimental estimates of per capita interaction strength and impact of consumers on prey by comparing our impact predictions with real‐time series of prey abundance. We conducted aquarium experiments to estimate the effects of seven herbivore species on survival of early life stages (microscopic sporophytes) of the giant kelp, Macrocystis pyrifera. We also estimated the impact of a community of herbivores on a cohort of kelp sporophytes using time series (1983–2000) of herbivore abundance in the Point Loma, San Diego (California), kelp forest. The underlying assumption was that maximum herbivore impact on microscopic recruits is realized only after a disturbance removes the giant kelp plants and thus releases the recruits. Our model was successful in predicting the prevention of giant kelp recruitment, which occurred when the abundance of weak interactors increased above a threshold. These results indicate that experimental estimates of maximum per capita interaction strength can be used to predict strong consumer impacts.
Relevance of Nitrospira for nitrite oxidation in a marine recirculation aquaculture system and physiological features of a Nitrospira marina‐like isolate
Authors: Keuter Sabine , Kruse Myriam , Lipski André , Spieck Eva
Published: August 2011

In biofilters of recirculation aquaculture systems (RAS), nitrification by lithoautotrophic microorganisms is essential to prevent the cultivated organisms from intoxication with ammonium and nitrite. In moving‐bed biofilters nitrifying microorganisms are immobilized together with heterotrophic bacteria in dense biofilms on carrier elements like plastic beads. Analyses of fatty acid profiles of these biofilms from a marine biofilter revealed a high abundance of Nitrospira‐related lipid markers (8–12% of total fatty acids). Further results of a labeling experiment with 13C‐bicarbonate in mineral salts medium with 3 mM nitrite confirmed that Nitrospira is the major autotrophic nitrite oxidizer in the biofilter system. According to 16S rRNA gene sequence analyses the nitrite‐oxidizing community in the biofilter consisted of at least two different representatives of Nitrospira, one of which could be successfully isolated. The marine isolate ‘Ecomares 2.1’ belongs to cluster IVa and showed 98.8% 16S rRNA gene sequence similarity to Nitrospira marina, whereas the enrichment ‘M1 marine’ is only distantly related (94.0% 16S rRNA gene sequence similarity to N. marina). In laboratory experiments, the isolate exhibited remarkable tolerances against high substrate and product concentrations (30 mM nitrite and 80 mM nitrate) as well as ammonium (50 mM). During the isolation process a strong tendency of this strain to develop biofilms became apparent. Thus, Ecomares 2.1 seems to be well adapted to the attached lifestyle in biofilters and the nitrogenous load prevailing in the effluent waters of RAS. Both members of Nitrospira could be detected by PCR‐based methods in environmental samples of marine and brackish RAS biofilters and are therefore considered to be characteristic for these engineered ecosystems.
THERMOPHYSICAL PROPERTIES OF HYDROLYZED BY‐PRODUCTS FROM THE MEAT INDUSTRY
Authors: DE OLIVEIRA GABRIELI ALVES , ZANOELO ÉVERTON FERNANDO
Published: August 2011

The method of mixtures, a pycnometric technique and a procedure based on an unsteady‐state condition of heat transfer were applied to obtain the specific heat, apparent density and thermal conductivity of processed by‐products from residuals of poultry slaughterhouses, respectively. Physical‐chemical analyses revealed that the investigated material presented 3.7% of water, 10.2% of ash, 8 to 25% of lipid and 37 to 60% of protein. The effect of moisture content and mass fraction of lipids on the aforementioned thermophysical properties was experimentally investigated at approximately 25C. Semiempirical models based on theoretical considerations and on the content of water, lipid and matter free of these components were suggested. A group of model parameters tuned on the experimental results revealed a specific heat, apparent density and thermal conductivity of dry processed by‐product without lipid close to 366 J/kg/C, 396 kg/m and 0.038 W/m/C, respectively.

PRACTICAL APPLICATIONS

A growing availability of residuals from poultry slaughterhouses is an important consequence of the large expansion of the poultry meat industry in Brazil. Excessive consumption of energy and large emission of non‐toxic odorous pollutants are the major current problems in the rendering industry. The determined thermophysical properties are essential for modeling and design calculations of cheaper and cleaner continuous industrial digesters that could replace the traditional technology of thermal hydrolysis of poultry by‐products.
GINGER–GARLIC PASTE IN RETORT POUCHES AND ITS QUALITY
Authors: TOPNO PRIYA NAMRATA , VINOTHINI  , JAYAPRAKASH SHILPA HABBANKUPPE , VARADAIAH VISHALAKSHI , SHESHAGIRI SATHISH HASAN , SRINIVAS PUSHPA MURTHY , NAIDU MADENENI MADHAVA
Published: August 2011

Paste samples were prepared by mixing 1:1 (w/w) proportion of ginger and garlic along with sodium chloride (1%). The pH of the paste was adjusted to 4.0, 4.5 and 5.4 by the addition of citric acid. Xanthan gum (2 g/L) and sodium benzoate (0.2 g/L) were added to the paste and then filled in retort pouches. The filled pouches were subjected to thermal processing at 85C with a holding time of 2 and 5 min at 80C at the centre of the paste. The color values a, and b (green and yellow) decreased, whereas the L (lightness) values increased with decrease in pH. Paste behaved like a non‐Newtonian fluid, and exhibited shear‐thinning behavior. Physicochemical and microbial properties did not show significant changes during storage. This study showed that ginger–garlic paste prepared in retort pouches is convenient because of its lighter weight, faster heating leading to better quality in terms of taste, color, and also environmentally acceptable.

PRACTICAL APPLICATIONS

Ginger and garlic have been considered as important traditional herbal medicines due to their disease prevention effects. Ginger–garlic paste is a viscous product retaining the strong aroma and flavor of the raw materials, namely, fresh ginger and garlic. Paste is mainly used as a spice in culinary preparations for imparting a characteristic fresh ginger–garlic flavor. The product is generally creamy white in color and is microbiologically stable and free from pathogenic bacteria. It is a ready to use preparation that can be used in place of fresh ginger in homes, restaurants and institutional catering. Although, few studies have been conducted on the physicochemical characteristics of ginger and garlic pastes, no information is available on combination of ginger–garlic paste in retort pouches. The development of new packing (retort pouches) for ginger–garlic with good nutritional and functional properties (such as the one proposed in this study) may be of interest in order to diversify the market supply. Therefore, retort pouch because of its lighter weight, and faster heating leads to better quality in terms of uniform cooking, taste and color and also it is environmentally acceptable.
RANK ORDER CLUSTER ANALYSIS1
Authors: Bromley D. B.
Published: August 2011

The relations between clusters and factors arc described and discussed. A method of rank order cluster analysis (abbreviated ROCA) is compared and contrasted with factor analysis; it appears to be effective in detecting clusters of functionally similar variables and defining the common function of each cluster. The method is simple and may prove to have some advantages for psychologists, although the end result of the analysis is a classification by functions and not components.
CLUSTER ANALYSIS OF NON‐VERBAL JUDGEMENTS OF FACIAL EXPRESSIONS
Authors: Stringer Peter
Published: August 2011

Previous researches on judgements of facial expressions have used either verbal scales, pre‐selected or elicited, or non‐verbal multidimensional techniques. Certain disadvantages in the methods so far used are described, and a simple alternative procedure is tested. Data from a ‘free‐grouping’ task are analysed by a clustering method which is congruent with the assumption that the primary response to facial expressions is in terms of contextual or functional similarity. The principal disjoint clusters obtained are described in detail. The meaning of the clusters and of their interrelationships is discussed. It is suggested that there are wider applications both of the ‘free‐grouping’ procedure and of cluster analysis.
ATTRIBUTE AND RELIABILITY
Authors: Ross John , Lumsden James
Published: August 2011

An analysis of classical test theory and of more recent developments shows that the concepts of true score, parallel test and reliability are poorly defined. Where reliability is defined as generalizability it is not so much poorly defined as detached from the essential interior properties of the test. It is proposed that tests as such be restrictively defined as devices which map an attribute in a single dimension. A logistic model which fits this conception is examined and it is shown that true score, parallel test and reliability can be defined without ambiguity, inconsistency or circularity. Deeper investigation reveals that the true score concept is not only unnecessary as a basis of reliability but also a distraction. Reliability is formulated as a characterization of the test's mapping. It is shown that the mapping can be characterized for the model and it is also shown that there is a distinction between information loss due to regression and error which probably lies behind the poorly conceived notion of true score.
QUADRATIC SIMILARITIES
Authors: Gregson R. A. M.
Published: August 2011

An axiom set for similarities is presented together with a set‐theoretic definition of multidimensional similarity consistent with the axioms. A special case of relative similarity judgement, involving the simultaneous comparison of three stimulus pairs, called ‘quadratic similarities’, is empirically illustrated and related to the theory. The goodness of fit of the axiomatic theory is checked for both unweighted and differentially weighted versions. Agreement generally varies between subjects, but in some cases is very good, and is almost invariably improved slightly by weighting.
LIKELIHOOD RATIO TESTS OF STATISTICAL HYPOTHESES ASSOCIATED WITH PATTERNED COVARIANCE MATRICES IN PSYCHOLOGY
Authors: Mukherjee Bishwa Nath
Published: August 2011

A number of statistical tests are proposed for testing whether an observed covariance matrix is consistent with an expected covariance matrix deduced from an assumed composition of the variates. This aspect of multivariate analysis has no univariate analogue and as yet has not received proper treatment in the statistical literature. The general method proposed has been called ‘structural analysis’ and its role in multivariate hypothesis‐testing is discussed.

Two different types of patterned covariance matrices arising out of various linear models are considered. The ‘reducible pattern’, composed of covariance matrices which can be diagonalized by pre‐ and post‐multiplication by a known matrix, and covariance matrices which can be transformed to a tridiagonal form (such as the Guttman quasi‐simplex, and the ‘aristocratic’ matrices), are discussed and illustrated with empirical data. Likelihood ratio tests for both classes of patterns have been constructed, and in each case the estimation procedure has also been tackled.
COMPARING THE MARGINAL TOTALS OF SQUARE CONTINGENCY TABLES
Authors: Fleiss Joseph L. , Everitt Brian S.
Published: August 2011

Suppose that each of a sample of subjects is assigned to one of m categories by one standard, and to one of the same m categories by a second standard. A comparison of the two resulting marginal distributions may be made by means of Stuart's and Maxwell's generalization of McNemar's test. Explicit expressions are given for the generalized statistic when m = 3 and m = 4. Methods are suggested for identifying those categories for which significant differences exist. A numerical example is given.
THE WPPSI: A MARKED DISCREPANCY IN THE CORRELATIONS OF THE SUBTESTS FOR GOOD AND POOR READERS
Authors: Maxwell A. E.
Published: August 2011

In this paper an attempt is made to explain a marked difference in the correlations between the subtests of the WPPSI for two samples of children who were respectively above and below average at reading. The use of WPPSI as a predictor of reading ability is also indicated.
Some theories of performance in multiple choice tests, and their implications for variants of the task
Authors: Hutchinson T. P.
Published: August 2011

Theories are put forward that attempt to answer the practical question of ‘How should we correct for guessing in multiple choice tests?’ and the theoretical question of ‘How can we mathematically describe partial knowledge so as to predict behaviour in tasks which enable it to be shown?’. Empirical findings relating to performance on variants of the multiple choice task are reviewed, and compared to the predictions of the theories.
The detection of outliers in free recall lists: An exploratory analysis
Authors: Robertson Chris
Published: August 2011

A number of methods which can be used to scan free recall lists are described. These methods will be of use in an initial exploratory analysis of responses with a view to checking the data before proceeding with more sophisticated analyses. The aim is to bring atypical recall patterns to the attention of the experimenter so that any aberrant data may be excluded if necessary or to allow such patterns to be studied further.
Variants of the method of triads: Utridimensional Thurstonian models
Authors: Ennis Daniel M. , Mullen Kenneth , Frijters Jan E. R.
Published: August 2011

This paper deals with a theory for two variants of the method of triads—Torgerson's and Richardson's methods. For both methods, the relationship between the decision probabilities and the parameters of the momentary psychological magnitudes is derived under the assumption that these magnitudes can be modelled as if they were drawn from normal distributions with particular means and variances. This approach differs from previous theoretical work on the methods of triads, where it has been assumed that distances between momentary psychological magnitudes are normally distributed. Cases where the variances of the distributions of psychological magnitudes are unequal can be handled by the models. It is shown that the duo‐trio and triangular methods are special cases of Torgerson's and Richardson's methods of triads, respectively. Using non‐linear least squares minimization, estimates of the means of the distributions of a sample problem are obtained for random samples of size 200. Decision conflicts, which may occur when using Richardson's method, are discussed.
An adaptive filter model for recognition memory
Authors: Heath Richard A. , Fulham Ross
Published: August 2011

A model for the adaptive formation of an associative memory structure based on a stochastic approximation algorithm is described. This model incorporates a feedback loop which allows the modification to memory to depend upon the novelty of the stimulus input. Predictions are derived for change in the memory structure across trials and these results are applied to the analysis of serial position effects in the Sternberg item‐recognition paradigm as well as familiarity judgements in a continuous recognition task. Illustrative applications of the model arc presented.
Three‐mode principal component analysis and perfect congruence analysis for sets of covariance matrices
Authors: Kroonenberg Pieter M. , ten Berge Jos M. F.
Published: August 2011

In this paper three‐mode principal component analysis and perfect congruence analysis for weights applied to sets of covariance matrices are explained and detailed, and the relationships between the two techniques are explored. It is shown that given several assumptions are made for three‐mode principal component analysis close links between the two techniques exist. The methods are illustrated with data pertaining to a theory of self‐concept.
Learning and the pace of lessons: A theoretical model
Authors: Preece Peter F. W.
Published: August 2011

An algebraic model relating the rate of learning to the pace of teaching and to pupil ability is described. The model accounts well for prior data on learning at different speeds and accurately predicts the learning deficit for able pupils taught in heterogeneous classes. The capacity of the model to predict changes of pace and learning from lesson to lesson is described.
Moments of the censored and truncated bivariate normal distribution
Authors: Muthén Bengt
Published: August 2011

Published results on the moments of censored and truncated bivariate normal distributions do not include explicit formulas for all combinations of limits in a form that is readily adapted for computation. Moments for truncation and censoring that can take place both from above and below in both variables are given in a general form from which special cases are easily obtained. The attenuation of the correlation coefficients is studied in a series of graphs and related to examples of factor analysis.
Analysis of multivariate polychoric correlation models with incomplete data
Authors: Lee Sik‐Yum , Chiu Yiu‐Ming
Published: August 2011

Several methods of analysing the multivariate polychoric correlation model with missing data are studied. They are the direct maximum likelihood method, the partition maximum likelihood method, the complete data method, the mean replacement method, the regression replacement method and the principal components method. Based on results of some simulation studies, the direct maximum likelihood method and the partition maximum likelihood method are recommended.
A multimode direct product model for covariance structure analysis
Authors: Verhees J. , Wansbeek T. J.
Published: August 2011

In the psychometric literature, there is evidence that the modes (facets, dimensions, etc.) in multimode data interact multiplicatively. A basic expression of this idea is that a covariance matrix may then be written as repeated Kronecker product of k, say, parameter matrices, where k is the number of modes. For such a ‘factorial covariance structure’ we give an integrated treatment of ML, WLS and ULS estimators. A modification of the ULS estimator appears to be non‐iteratively computable.
Determining whether an experimental group is stochastically larger than a control
Authors: Wilcox Rand R.
Published: August 2011

Let μx and μy be the means of a control and an experimental group, respectively. The usual method of comparing the two groups is in terms of μx‐μy by testing H0:μx = μy. This approach might suffice when the corresponding distributions differ only in location. When the distributions differ in other respects, a shift function can be more informative. For example, it might be the case that the typical subjects who perform poorly under a standard method will, on the average, benefit from a new treatment, while the new treatment is actually detrimental for the typical subject who does well under the established procedure. Another possibility, which is illustrated in the paper, is that μy>μx might be true even though for most subjects the experimental group is detrimental. This paper describes a simple method for determining whether these situations have occurred.
Approximate confidence intervals for the correlation from data in two‐by‐two tables
Authors: Bedrick Edward J.
Published: August 2011

The family of power divergence statistics is used to construct approximate confidence intervals for the correlation between two variables from data in 2×2 tables. This family includes confidence intervals obtained by inverting the likelihood ratio, Pearson chi‐squared and Freeman–Tukey statistics. Small‐sample calculations show that several power divergence intervals, and in particular the confidence interval constructed from the Pearson chi‐squared statistic, have coverage probabilities closer to nominal levels than the interval based on the normal approximation to the tetrachoric correlation coefficient.
Two‐level analysis of covariance structures for unbalanced designs with small level‐one samples
Authors: Lee Sik‐Yum , Poon Wai‐Yin
Published: August 2011

The main purpose of this paper is to develop basic statistical theory for two‐level analysis of covariance structures. Major asymptotic results for statistical inference, such as the asymptotic distributions of the estimator and the goodness‐of‐fit test statistic are derived, based on an unbalanced design with only small numbers of level‐one units. Computationally, it is shown that the solution can be obtained via standard programs, such as LISREL, EQS and COSAN. The behaviour of the estimates is illustrated by an artificial example and a real‐life example. Some possibilities of extending the results to a more general two‐level model, and to situations with arbitrary distributions and elliptical distributions are also investigated.
Selection and predictive validity with latent variable structures†
Authors: Muthén Bengt O. , Hsu Jin‐Wen Yang
Published: August 2011

Estimators of the predictive validity of a multifactorial test are considered. These estimators take into account the selectivity of the sample of those who have observations on the criterion measure. It is pointed out that the selectivity problem can be viewed as a missing data situation. The relationships between the classic Pearson‐Lawley adjustment, regression based on factor scores, and maximum‐likelihood estimation under ignorable missingness are described. The estimators are compared in a study of artificial population data.
Psychological scaling of the asymmetry observed in comparative judgement
Authors: Saito Takayuki
Published: August 2011

This paper gives two scaling procedures for measurement of asymmetry observed in comparative judgement in terms of three ordered categories. With a revised law of comparative judgement, a least squares solution and a maximum likelihood solution are suggested for the parameter estimation with some statistical tests. Numerical examples are illustrated, and features and applicability of the present work are discussed in comparison with related work.
Sampling behaviour in estimating predictive validity in the context of selection and latent variable modelling: A Monte Carlo study
Authors: Hsu Jin‐Wen Yang
Published: August 2011

While the effect of selection in predictive validity studies has long been recognized and discussed in psychometric studies, little consideration has been given to this problem in the context of latent variable models. In a recent paper, Muthén & Hsu (1993) proposed and compared estimators of predictive validity of a multifactorial test. Both selectivity and measurement error were considered in the estimation of predictive validity. The purpose of the present paper is to expand on Muthén & Hsu (1993) by examining and comparing the sampling behaviour of three estimators for predictive validity, LQL (listwise, quasi‐likelihood estimator), FQL (full, quasi‐likelihood estimator) and FS (factor score estimator), using a Monte Carlo approach. Effects of selection procedures, selection ratios and sample sizes on the sampling behaviours of the estimators are also investigated. The results show that FQL and FS are the two preferred estimators and each has different strengths and weaknesses. A real data application is presented to illustrate the practical implementation of the estimators.
Simultaneous optimization of quota‐restricted selection decisions with mastery scores
Authors: Vos Hans J.
Published: August 2011

Combinations of elementary test‐based decisions in psychology and education arise when one decision problem leads to another, which, in turn, may lead to a third one, and so on. An example is test‐based decision making in computer‐aided instruction (CAI) in education. Such systems can be described as instructional networks with individual routes for the students. The purpose of this paper is to formulate optimal rules for deciding on such routes using data from achievement tests and data gathered at earlier decisions in the network. As an example, a common decision problem in education and psychology, consisting of a quota‐restricted selection decision for a treatment followed by a mastery decision, is analysed in the case of several relevant subpopulations. The quota‐restricted selection and mastery decisions are optimized simultaneously using the framework of Bayesian decision theory. Conditions for optimal simultaneous rules to be monotone are presented. Results from an empirical example of instructional decision making in CAI will be presented to illustrate the differences between simultaneous optimization of the quota‐restricted selection and mastery decisions and optimizing each of the two decisions separately.
Distance analysis of large data sets of categorical variables using object weights
Authors: Groenen Patrick J. F. , Commandeur Jacques J. F. , Meulman Jacqueline J.
Published: August 2011

Categorical variables are often analysed by multiple correspondence (or homogeneity analysis), which places great emphasis on graphical representation. A drawback of this method is that sometimes only minor aspects of the data are displayed, or, if a dominant first dimension exists, the horseshoe effect occurs. Here, we elaborate on a competing approach to multiple correspondence analysis based on distance approximation. This method emphasizes the distance between objects; they are graphically displayed as points, and objects close together are considered more similar than objects farther apart. A limiting factor of this method is that the number of objects cannot be very large (say, no more than 500). We show how the majorization algorithm for distance approximation can be extended using frequency counts as object weights such that much larger data sets can be analysed without a significant amount of additional computational effort. A second advantage of the use of object weights is that resampling methods, such as the bootstrap, are easily implemented. We present two illustrative examples, and investigate the stability in one of them through the bootstrap.
Subcutaneous electronic identification in cattle: a field study
Authors: Løken T. , Vatn G. , Kummen E.
Published: August 2011

The use of injectable transponders in cattle for identification purposes, for up to 30 months, was investigated. Passive electronic transponders, encapsulated in either polymer or glass, were injected subcutaneously into either the ear base or the earlobe of 652 calves in three populations. The animals were clinically examined weekly, and transponder signalling was checked immediately before and after injection, after two weeks and after about eight months. About 10 per cent of animals in one population were also checked after 20 and 30 months. No severe clinical or visible pathological changes were observed, and the calves' welfare was not apparently affected by the procedure. None of the transponders migrated from their injection sites. Eight months after injection, a signal was detected from 98.2 per cent of transponders injected in the ear base and from 90.5 per cent of those in the earlobe. At 20 and 30 months after injection, 10.4 per cent and 2.6 per cent of transponders, respectively, had ceased to signal. Thus, most transponders in the calves' ear base demonstrated functionality for up to 30 months.
A solid-state 35/37Cl NMR study of a chloride ion receptor and a GIPAW-DFT study of chlorine NMR interaction tensors in organic hydrochlorides
Authors: Chapman Rebecca P. , Hiscock Jennifer R. , Gale Philip A. , Bryce David L.
Published: August 2011

The results of a 35/37Cl solid-state nuclear magnetic resonance (SSNMR) study of the 1-butyl-3-methylimidazolium chloride complex of meso-octamethylcalix[4]pyrrole (1) are reported. Line shapes obtained from magic-angle-spinning and stationary powder samples collected at 9.4 and 21.1 T are analyzed to provide the 35/37Cl quadrupolar tensor and chemical shift (CS) tensor and their relative orientation. The relatively high symmetry of the chloride ion coordination environment is manifested in the small value of the quadrupole coupling constant, CQ(35Cl) = 1.0 MHz. The isotropic chemical shift of 120 ppm (with respect to NaCl(s)) is at the upper edge of the typical range seen for organic hydrochlorides. Consideration of chemical shift anisotropy (span, Ω = 50 ppm) and non-coincidence of the quadrupolar and CS tensors were essential to properly simulate the experimental spectra. The utility of gauge-including projector-augmented wave density functional theory (GIPAW-DFT) calculations of chlorine quadrupolar and CS tensors in organic chlorides was explored by validation against available benchmark experimental data for solid amino acid hydrochlorides. The calculations are shown to systematically overestimate the value of the 35Cl quadrupole coupling constant. Additional calculations on various hydrated and solvated models of 1 are consistent with a structure in which solvent and water of hydration are absent.
SR59230A, a beta-3 adrenoceptor antagonist, inhibits ultradian brown adipose tissue thermogenesis and interrupts associated episodic brain and body heating
Authors: Ootsuka Youichirou , Kulasekara Keerthi , de Menezes Rodrigo Cunha , Blessing William W.
Published: August 2011

Brown adipose tissue (BAT) thermogenesis occurs episodically in an ultradian manner approximately every 80–100 min during the waking phase of the circadian cycle, together with highly correlated increases in brain and body temperatures, suggesting that BAT thermogenesis contributes to brain and body temperature increases. We investigated this in conscious Sprague-Dawley rats by determining whether inhibition of BAT thermogenesis via blockade of beta-3 adrenoceptors with SR59230A interrupts ultradian episodic increases in brain and body temperatures and whether SR59230A acts on BAT itself or via sympathetic neural control of BAT. Interscapular BAT (iBAT), brain, and body temperatures, tail artery blood flow, and heart rate were measured in unrestrained rats. SR59230A (1, 5, or 10 mg/kg ip), but not vehicle, decreased iBAT, body, and brain temperatures in a dose-dependent fashion (log-linear regression P < 0.01, R2= 0.3, 0.4, and 0.4, respectively, n = 10). Ultradian increases in BAT, brain, and body temperature were interrupted by administration of SR59230A (10 mg/kg ip) compared with vehicle, resuming after 162 ± 24 min (means ± SE, n = 10). SR59230A (10 mg/kg ip) caused a transient bradycardia without any increase in tail artery blood flow. In anesthetized rats, SR59230A reduced cooling-induced increases in iBAT temperature without affecting cooling-induced increases in iBAT sympathetic nerve discharge. Inhibition of BAT thermogenesis by SR59230A, thus, reflects direct blockade of beta-3 adrenoceptors in BAT. Interruption of episodic ultradian increases in body and brain temperature by SR59230A suggests that BAT thermogenesis makes a substantial contribution to these increases.
FM velocity selectivity in the inferior colliculus is inherited from velocity-selective inputs and enhanced by spike threshold
Authors: Gittelman Joshua X. , Li Na
Published: August 2011

Frequency modulation (FM) is computed from the temporal sequence of activated auditory nerve fibers representing different frequencies. Most studies in the inferior colliculus (IC) have inferred from extracellular recordings that the precise timing of nonselective inputs creates selectivity for FM direction and velocity (Andoni S, Li N, Pollak GD. J Neurosci 27: 4882–4893, 2007; Fuzessery ZM, Richardson MD, Coburn MS. J Neurophysiol 96: 1320–1336, 2006; Gordon M, O'Neill WE. Hear Res 122: 97–108, 1998). We recently reported that two additional mechanisms were more important than input timing for directional selectivity in some IC cells: spike threshold and inputs that were already selective (Gittelman JX, Li N, Pollak GD. J Neurosci 29: 13030–13041, 2009). Here, we show that these same mechanisms, selective inputs and spike threshold, underlie selectivity for FM velocity and intensity. From whole cell recordings in awake bats, we recorded spikes and postsynaptic potentials (PSPs) evoked by downward and upward FMs that swept identical frequencies at different velocities and intensities. To determine the synaptic mechanisms underlying PSP selectivity (relative PSP height), we derived sweep-evoked synaptic conductances. Changing FM velocity or intensity changed conductance timing and size. Modeling indicated that excitatory conductance size contributed more to PSP selectivity than conductance timing, indicating that the number of afferent spikes carried more FM information to the IC than precise spike timing. However, excitation alone produced mostly suprathreshold PSPs. Inhibition reduced absolute PSP heights, without necessarily altering PSP selectivity, thereby rendering some PSPs subthreshold. Spike threshold then sharpened selectivity in the spikes by rectifying the smaller PSPs. This indicates the importance of spike threshold, and that inhibition enhances selectivity via a different mechanism than previously proposed.
I-CLIP: Improved Stratification of Advanced Hepatocellular Carcinoma Patients by Integrating Plasma IGF-1 into CLIP Score
Authors: Kaseb Ahmed O. , Abbruzzese James L. , Vauthey Jean-Nicolas , Aloia Thomas A. , Abdalla Eddie K. , Hassan Manal M. , Lin E. , Xiao Lianchun , El-Deeb Adel S. , Rashid Asif , Morris Jeffrey S.
Published: August 2011

Objective: Improving the prognostic stratification of unresectable hepatocellular carcinoma (HCC) patients is critically needed. Since patients’ survival is closely linked to the severity of the underlying liver disease, and insulin-like growth factor-1 (IGF-1) is produced predominantly in the liver, we hypothesized that IGF-1 may correlate with patients’ survival and hence improve the prognostic ability of the Cancer of the Liver Italian Program (CLIP) score. Methods: Baseline plasma IGF-1 and clinicopathologic parameters were available from 288 patients. Multivariate Cox regression models, Kaplan-Meier curves, and the log-rank test were applied. Recursive partitioning was used to determine the optimal cut point for IGF-1 using training/validation samples. Prognostic ability of the I-CLIP (I = IGF) was compared to CLIP using C-index. Results: IGF-1 significantly correlated with the clinicopathologic features. With an optimal IGF-1 cut point of 26 ng/ml, the overall survival of patients with IGF-1 >26 was 17.7 months (95% CI 13.6–22.8), and with IGF-1 ≤26 was 5.8 months (95% CI 4.0–12.5), p < 0.0001. The concordance probabilities for CLIP and I-CLIP were 0.7037 and 0.7096, respectively (p < 0.0001). Conclusions: Our preliminary results indicate that I-CLIP significantly improved prognostic stratification of patients with advanced HCC. However, independent validation of our study is warranted.
Audiometric Records Analysis in a Clinical Population in China
Authors: Liu Haihong , Zhang Hua , Bentler Ruth A. , Mo Lingyan , Han Demin , Zhang Luo
Published: August 2011

Objective:The objective of this study was to characterize the typical hearing loss presenting at a clinical audiology center.Methods: Audiometric records for 8,032 cases were obtained from the database at Beijing Tongren Hospital, Capital Medical University. Based on this information, age distribution, audiometric configuration, type, degree and asymmetry of hearing loss were characterized. Results: Results showed that 48.4% of all cases of hearing loss occurred from 31 to 60 years of age, sloping hearing loss was the most common audiometric configuration, and sensorineural hearing loss dominated the type of hearing loss for both males and females. Mean pure-tone hearing thresholds revealed significant differences between genders, that is, thresholds for females were poorer than those for males from 250 to 1,000 Hz, whereas thresholds for males were poorer than those for females from 2,000 to 8,000 Hz. Analysis showed that 57.3% of audiograms showed some degree of asymmetry. No significant difference was found between genders for the average asymmetric thresholds. Conclusion: This study provides the characteristics of age distribution, audiometric configuration, type, degree and asymmetry of hearing loss from a representative clinical audiology center. These data are useful for public policy efforts involving hearing loss prevention and rehabilitative program development.
Improving Perceptions of Teamwork Climate With the Veterans Health Administration Medical Team Training Program
Authors: Carney Brian T. , West Priscilla , Neily Julia B. , Mills Peter D. , Bagian James P.
Published: August 2011

There are differences between nurse and physician perceptions of teamwork. The purpose of this study was to determine whether these differences would be reduced with medical team training (MTT). The Safety Attitudes Questionnaire was administered to nurses and physicians working in the operating rooms of 101 consecutive hospitals before and at the completion of an MTT program. Responses to the 6 teamwork climate items on the Safety Attitudes Questionnaire were analyzed using nonparametric testing. At baseline, physicians had more favorable perceptions on teamwork climate items than nurses. Physicians demonstrated improvement on all 6 teamwork climate items. Nurses demonstrated improvement in perceptions on all teamwork climate items except “Nurse input is well received.” Physicians still had a more favorable perception than nurses on all 6 teamwork climate items at follow-up. Despite an improvement in perceptions by physicians and nurses, baseline nurse–physician differences persisted at completion of the Veterans Health Administration MTT Program.
Staging Realism and the Ambivalence of Nationalism in the Colonial Novel
Authors: Anjaria Ulka
Published: August 2011

This essay moves away from accounts of social realism, which privilege its political aims over its aesthetic innovations. I argue that social realism written under colonialism was part of a larger intellectual project to rethink the desirability and content of nationalism by testing the limitations and plasticity of the realist mode. I look specifically at moments of self-referentiality in social realist writing as well as in the repeated claims by writers themselves about the mimetic purpose of social realism. In this way, I show how literary realism in the colony lived the dual life of representing the material world and taking on a materiality of its own, as language marked by aspiration and potentiality. This “projective realism” is epitomized by Ahmed Ali's 1940 novel Twilight in Delhi. Twilight, by offering an interpretation of history as a performance, a series of snapshots, and gestures definable in synchronic time, provides an idiom from which to rethink the conventional discourse upon which nationalism is founded and raises a profound ambivalence as to which nation this “nationalist” novel in fact references.
The Satanic Verses and the Politics of Extremity
Authors: Ho Janice
Published: August 2011

This essay situates Salman Rushdie's The Satanic Verses within the historical context of a politics of extremity that was mobilized by ethnic migrants in postwar Britain in their struggles against racism. Such a politics—characterized by the discourses of war, militancy, rioting, and heat—was fashioned as an implicit challenge to a tradition of moderate English liberalism that had failed to provide minorities with an adequate platform for redressing the systemic inequities caused by racial discrimination. The essay shows how The Satanic Verses is structured by an ambivalent and conflicted response to this genealogy of political extremism: the novel inhabits various discourses of extremity to critique liberalism's depoliticizing strategies and to herald the birth of alternative political formations, but it simultaneously recoils from the violence that a radicalized politics seems to entail. The text attempts to resolve this conflict by turning to magical realism as a formal device for obscuring the material effects of violence; in doing so, it reprises a liberal ethics in the way its representational form seeks to contain and moderate the politics of extremity.
Monocarboxylate transporter 8 deficiency: altered thyroid morphology and persistent high triiodothyronine/thyroxine ratio after thyroidectomy
Authors: Wirth Eva K , Sheu Sien-Yi , Chiu-Ugalde Jazmin , Sapin Remy , Klein Marc O , Mossbrugger Ilona , Quintanilla-Martinez Leticia , Hrabě de Angelis Martin , Krude Heiko , Riebel Thomas , Rothe Karin , Köhrle Josef , Schmid Kurt W , Schweizer Ulrich , Grüters Annette
Published: August 2011

Context

Thyroid hormone transport across the plasma membrane depends on transmembrane transport proteins, including monocarboxylate transporter 8 (MCT8). Mutations in MCT8 (or SLC16A2) lead to a severe form of X-linked psychomotor retardation, which is characterised by elevated plasma triiodothyronine (T3) and low/normal thyroxine (T4). MCT8 contributes to hormone release from the thyroid gland.

Objective

To characterise the potential impact of MCT8-deficiency on thyroid morphology in a patient and in Mct8-deficient mice.

Design

Thyroid morphology in a patient carrying the A224V mutation was followed by ultrasound imaging for over 10 years. After thyroidectomy, a histopathological analysis was carried out. The findings were compared with histological analyses of mouse thyroids from the Mct8−/y model.

Results

We show that an inactivating mutation in MCT8 leads to a unique, progressive thyroid follicular pathology in a patient. After thyroidectomy, histological analysis revealed gross morphological changes, including several hyperplastic nodules, microfollicular areas with stromal fibrosis and a small focus of microfollicular structures with nuclear features reminiscent of papillary thyroid carcinoma (PTC). These findings are supported by an Mct8-null mouse model in which we found massive papillary hyperplasia in 6- to 12-month-old mice and nuclear features consistent with PTC in almost 2-year-old animals. After complete thyroidectomy and substitution with levothyroxine (l-T4), the preoperative, inadequately low T4 and free T4 remained, while increasing the l-T4 dosage led to T3 serum concentrations above the normal range.

Conclusions

Our results implicate peripheral deiodination in the peculiar hormonal constellation of MCT8-deficient patients. Other MCT8-deficient patients should be closely monitored for potential thyroid abnormalities.
Transmission Electron Miscroscopy Study of the Fused Silicon/Diamond Interface
Authors: Yushin G. N. , Wolter S. D. , Kvit A. V. , Collazo R. , Prater J. T. , Sitar Z.
Published: August 2011

Bonding of polished, polycrystalline diamond films to silicon was performed in ultra high vacuum at 32 MPa of applied uniaxial stress. The transmission electron microscopy (TEM) investigation revealed that the interface of all bonded samples was non-uniform. An abrupt boundary between the two wafers existed only in some parts of the interface, while other parts contained an amorphous interlayer of up to 40 nm in thickness. Electron energy loss spectroscopy (EELS) revealed that this interlayer consisted of oxygen, carbon and silicon. Based on comparison of the microstructure and chemical composition of the interface formed at different bonding temperatures, we propose a model for the silicon/diamond wafer fusion process.