bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of the effect of different prefabricated intracanal posts on fracture resistance of simulated immature teeth
Authors: Dikbas Idil , Tanalp Jale , Koksal Temel , Yalnız Ayşe , Güngör Tufan
Published: February 2013

Aim

The aim of this study was to assess fracture resistances of simulated immature single‐rooted teeth whose roots have been backfilled using 3 different post systems after a 4 mm apical mineral trioxide aggregate (MTA) placement.

Materials and methods

Forty‐eight maxillary anterior teeth were assigned into four groups. The lengths of each root were standardized by cutting off the coronal and apical portions to obtain 13 ± 1 mm samples and root canals were enlarged. The #6 Peeso reamers were allowed to protrude 1 mm beyond apex to simulate immature teeth. Apical 4 mm of each tooth was filled using MTA. The remaining portions were treated as follows: Group 1 (Control): AH Plus + Gutta‐percha cold lateral compaction. Group 2: Glass fiber posts (FRC Postec Plus post) cemented using self‐adhesive resin cement. Group 3: Quartz fiber posts (D.T. Light post) cemented using self‐adhesive resin cement. Group 4: Zirconia posts (Cosmopost) were placed using self‐adhesive resin cement. Specimens were embedded in self‐curing acrylic. A compressive load was applied lingually at a crosshead speed of 1 mm/min at an angle of 45º until fracture in a universal testing machine.

Results

The mean fracture resistances were 823.17 ± 188.80, 1155.50 ± 190.37, 1208.00 ± 254.32, and 1153.25 ± 195.71 Newtons for Groups 1, 2, 3, and 4, respectively. All experimental groups had significantly higher fracture resistance compared with the control group (P < 0.01). No statistically significant difference was noted between the experimental groups (P > 0.05).

Conclusions

All post systems exerted a similar reinforcing effect to a simulated immature tooth and may be preferred specifically in situations which require additional reinforcement.
Dutch elm disease pathogen transmission by the banded elm bark beetle Scolytus schevyrewi
Authors: Jacobi W. R. , Koski R. D. , Negron J. F.
Published: February 2013

Dutch Elm Disease (DED) is a vascular wilt disease of Ulmus species (elms) incited in North America primarily by the exotic fungus Ophiostoma novo‐ulmi. The pathogen is transmitted via root grafts and elm bark beetle vectors, including the native North American elm bark beetle, Hylurgopinus rufipes and the exotic smaller European elm bark beetle, Scolytus multistriatus. The banded elm bark beetle, Scolytus schevyrewi, is an exotic Asian bark beetle that is now apparently the dominant elm bark beetle in the Rocky Mountain region of the USA. It is not known if S. schevyrewi will have an equivalent vector competence or if management recommendations need to be updated. Thus the study objectives were to: (i) determine the type and size of wounds made by adult S. schevyrewi on branches of Ulmus americana and (ii) determine if adult S. schevyrewi can transfer the pathogen to American elms during maturation feeding. To determine the DED vectoring capability of S. schevyrewi, newly emerged adults were infested with spores of Ophiostoma novo‐ulmi and then placed with either in‐vivo or in‐vitro branches of American elm trees. The inoculation of trees via feeding wounds was successful 30% of the time for in‐vivo trials and 33% for in‐vitro trials. Although the infection rate of DED has declined in Colorado over the past 10 years, the disease is still present in urban elms. While it appears that S. schevyrewi is another vector of the DED pathogens, it appears that S. schevyrewi is no more efficient than S. multistriatus. Thus, management programs that remove elm bark beetle breeding sites, rapidly remove DED‐infected elms and include the planting of DED‐resistant elms should continue to be effective management tactics.
Rapid visual stimulation increases extrasynaptic glutamate receptor expression but not visual‐evoked potentials in the adult rat primary visual cortex
Authors: Eckert M. J. , Guévremont D. , Williams J. M. , Abraham W. C.
Published: February 2013

The model most used to study synaptic plasticity, long‐term potentiation (LTP), typically employs electrical stimulation of afferent fibers to induce changes in synaptic strength. It would be beneficial for understanding the behavioral relevance of LTP if a model could be developed that used more naturalistic stimuli. Recent evidence suggests that the adult visual cortex, previously thought to have lost most of its plasticity once past the critical period, is in fact capable of LTP‐like changes in synaptic strength in response to sensory manipulations alone. In a preliminary study, we used a photic tetanus (PT; flashing checkerboard stimulus) to induce an enhancement of the visual‐evoked potential (VEP) in the primary visual cortex of anesthetised adult rats. In the present study, we sought to compare the mechanisms of this novel sensory LTP with those of traditional electrical LTP. Unexpectedly, we found that sensory LTP was not induced as reliably as we had observed previously, as manipulations of several parameters failed to lead to significant potentiation of the VEP. However, we did observe a significant increase in visual cortex glutamate receptor expression on the surface of isolated synapses following the PT. Both AMPA receptor expression and N‐methyl‐d‐aspartate (NMDA) receptor subunit expression were increased, specifically in extrasynaptic regions of the membrane, in PT animals. These results provide biochemical confirmation of the lack of change in the VEP in response to PT, but suggest that PT may prime synapses for strengthening upon appropriate subsequent activation, through the trafficking of glutamate receptors to the cell surface.
The brain's specialized systems for aesthetic and perceptual judgment
Authors: Ishizu T. , Zeki S.
Published: February 2013

We recorded brain activity when 21 subjects judged the beauty (aesthetic or affective judgment) and brightness (perceptual or cognitive judgment) of simultaneously presented paintings. Aesthetic judgments engaged medial and lateral subdivisions of the orbitofrontal cortex as well as subcortical stations associated with affective motor planning (globus pallidus, putamen–claustrum, amygdala, and cerebellar vermis), whereas the motor, premotor and supplementary motor areas, as well as the anterior insula and the dorsolateral prefrontal cortex, were engaged by both kinds of judgment. The results lead us to conclude: (i) that there is a functional specialization for judgment, with aesthetic judgments engaging distinct systems, in addition to those that they share with perceptual judgments; (ii) that the systems engaged by affective judgments are those in which activity correlates with polar experiences (e.g. love–hate, beauty–ugliness, and attraction–repulsion); and (iii) that there is also a functional specialization in the motor pathways, with aesthetic judgments engaging motor systems not engaged by perceptual judgments, in addition to those engaged by both kinds of judgment.
Oceanographic connectivity and environmental correlates of genetic structuring in Atlantic herring in the Baltic Sea
Authors: Teacher Amber GF , André Carl , Jonsson Per R , Merilä Juha
Published: February 2013

Marine fish often show little genetic structuring in neutral marker genes, and Atlantic herring (Clupea harengus) in the Baltic Sea are no exception; historically, very low levels of population differentiation (FST ≈ 0.002) have been found, despite a high degree of interpopulation environmental heterogeneity in salinity and temperature. Recent exome sequencing and SNP studies have however shown that many loci are under selection in this system. Here, we combined population genetic analyses of a large number of transcriptome‐derived microsatellite markers with oceanographic modelling to investigate genetic differentiation and connectivity in Atlantic herring at a relatively fine scale within the Baltic Sea. We found evidence for weak but robust and significant genetic structuring (FST = 0.008) explainable by oceanographic connectivity. Genetic differentiation was also associated with site differences in temperature and salinity, with the result driven by the locus Her14 which appears to be under directional selection (FST = 0.08). The results show that Baltic herring are genetically structured within the Baltic Sea, and highlight the role of oceanography and environmental factors in explaining this structuring. The results also have implications for the management of herring fisheries, the most economically important fishery in the Baltic Sea, suggesting that the current fisheries management units may be in need of revision.
The heparanase/syndecan‐1 axis in cancer: mechanisms and therapies
Authors: Ramani Vishnu C. , Purushothaman Anurag , Stewart Mark D. , Thompson Camilla A. , Vlodavsky Israel , Au Jessie L‐S. , Sanderson Ralph D.
Published: February 2013

Heparanase is an endoglucuronidase that cleaves heparan sulfate chains of proteoglycans. In many malignancies, high heparanase expression and activity correlate with an aggressive tumour phenotype. A major consequence of heparanase action in cancer is a robust up‐regulation of growth factor expression and increased shedding of syndecan‐1 (a transmembrane heparan sulfate proteoglycan). Substantial evidence indicates that heparanase and syndecan‐1 work together to drive growth factor signalling and regulate cell behaviours that enhance tumour growth, dissemination, angiogenesis and osteolysis. Preclinical and clinical studies have demonstrated that therapies targeting the heparanase/syndecan‐1 axis hold promise for blocking the aggressive behaviour of cancer.
Fish assemblages in theSouthernCaliforniaCurrent: relationships with climate, 1951–2008
Authors: Anthony Koslow J. , Goericke Ralf , Watson William
Published: February 2013

We examined the dominant patterns of variability in the fish fauna of the southernCaliforniaCurrent based on a principal component (PC) analysis of theCaliforniaCooperativeOceanicFisheriesInvestigations ichthyoplankton data set, 1951–2008. Eighty‐six taxa were analyzed, including all ecologically dominant fish species, both exploited and unexploited. The first threePCs accounted for 20.5, 12.4 and 6.8% of the variance of the data, respectively (total: 39.7%). Each was dominated by taxa from particular adult or larval habitats.PC1 predominantly represented the coherent response of 24 mesopelagic taxa from 10 families and was most highly correlated with long‐term trends in midwater oxygen levels.PC2 was dominated by six of the seven most abundant ichthyoplankton taxa in the region, predominantlyCaliforniaCurrent endemics including key pelagic species (northern anchovy,Pacific sardine andPacific hake), rockfishes (genusSebastes) and two midwater taxa. It was correlated primarily with sea surface temperature and exhibited a significant declining trend.PC3 was dominated by coastal and reef‐associated fishes with predominantly southerly affinities. It was positively correlated with sea surface temperature and sea level height, a proxy for diminished flow of theCaliforniaCurrent. The taxa dominatingPCs 2 and 3 mostly spatially co‐occur as ichthyoplankton. These results suggest that fish assemblages in theCaliforniaCurrent are predominantly influenced by environmental forcing of their ocean habitats as adults or larvae, or both.
Plant growth, water relations and proline content of three vetch species under water‐limited conditions
Authors: Haffani S. , Mezni M. , Slama I. , Ksontini M. , Chaïbi W.
Published: February 2013

Vetch species (Vicia narbonensis, V. sativa and V. villosa) are widely used for fodder production in Tunisia. This study aims to investigate vetch strategies involved in drought resistance through morphological and physiological criteria. Plants were sown in pots and subjected to four soil‐water levels: 100% (control), 80, 60 and 40% of field capacity (FC). After 133 d of water treatment, and under well‐watered conditions, V. narbonensis showed the largest plant height and shoot and root dry matter and the highest leaf relative water content and water potential (Ψw), whereas V. sativa had the greatest leaf area (LA). At the 40% FC treatment, V. narbonensis showed smaller decreases in plant height and LA, and the greatest reduction in Ψw (140%). Thus, it shows better adaptation and a more equilibrated water balance, despite having accumulated less proline than the two other species. Vicia sativa and V. villosa showed a similar behaviour under water stress with a superiority of the latter. Vicia sativa was the species most affected in terms of its growth and water‐status parameters. Vetch species mainly used avoidance mechanisms to withstand drought, with V. narbonensis showing the highest tolerance.
Silage quality and preservation of Urtica cannabina ensiled alone and with additive treatment
Authors: Zhang X. Q. , Jin Y. M. , Zhang Y. J. , Yu Z. , Yan W. H.
Published: February 2013

Urtica cannabina (U. cannabina), a member of the Urticaceae family, is widely distributed throughout the temperate regions of the world and can be used as a nutritious feed for animals through the winter period. To provide high‐quality forage all year‐round, we treated freshly harvested U. cannabina without additives (control), but with corn flour (CF) (5:1 w/w), molasses (2, 4, and 8% fresh weight), or LalsiL Dry (LD) inoculant (5, 10 and 20 mg kg−1 of fresh weight). We then assessed the chemical composition, in vitro digestibility and fermentative parameters of the products after 0, 3, 5, 15, 20 and 60 d of ensiling. The results showed that: (i) U. cannabina had large quantities of protein and some essential minerals, including calcium, potassium, sodium, zinc, copper and manganese, and was particularly rich in magnesium and iron. (ii) U. cannabina can be preserved as a highly nutritious silage. No additive treatment or the LD inoculant treatments produced badly preserved silages. The 2% molasses treatment produced badly preserved silage, but 4–8% molasses produced well‐preserved silages. The CF treatment also produced well‐preserved silage. We recommend the application rates of molasses at 4–8% of fresh weight or 5:1 CF to improve U. cannabina silage.
The Effect of Particle Size on the Mechanical and Microstructural Properties of Freeze‐Casted Macroporous Hydroxyapatite Scaffolds
Authors: Zamanian Ali , Farhangdoust Sajad , Yasaei Mana , Khorami Mina , Hafezi Masoud
Published: February 2013

Two different hydroxyapatites with the particle sizes of 3.9 and 1.69 μm were chosen. Slurries with initial hydroxyapatite concentration of 15 vol% were prepared. Different cooling rates from 2 to 14°C/min were utilized. The specimens were sintered at different temperatures of 1250–1350°C. The phase composition (by X‐Ray Diffraction), microstructure (by Scanning Electron Microscopy), mechanical characteristics, and the porosity of sintered samples were assessed. The porosity of the sintered samples was in range of ~57–83%, and the compressive strength varied from ~1.7 to 15 MPa. The mechanical strength of the scaffolds increased as a function of cooling rate and sintering temperature.
Production of Al2O3‐Stabilized Tetragonal ZrO2 Nanoparticles for Thermal Barrier Coating
Authors: Karthik Arumugam , Manivasakan Palanisamy , Arunmetha Sundaramoorthy , Yuvakkumar Rathinam , Rajendran Venkatachalam
Published: February 2013

Al2O3‐stabilized tetragonal ZrO2 nanoparticles were obtained through hot‐air spray pyrolysis and characterized after postsynthesized treatments. The produced nanoparticles were 26 nm in size with surface area of 59 m2/g. A multilayer thermal barrier coating of nanostructured Al2O3‐ZrO2‐embedded silicate was applied to the mild steel (EN3) specimen using spin‐coating technique and characterized comprehensively employing X‐ray diffraction and scanning electron microscope. The Al2O3‐stabilized ZrO2 with silicate matrix facilitates the formation of zirconium silicate nanostructured surface‐protective coating on EN3 specimen. The Al2O3‐ZrO2/SiO2 matrix‐based hybrid inorganic coating shows effective thermal barrier for EN3 after firing at a high temperature of 600°C.
Production and stability of water‐dispersible astaxanthin oleoresin from Phaffia rhodozyma
Authors: Villalobos‐Castillejos Fidel , Cerezal‐Mezquita Pedro , Hernández‐De Jesús Maria Lourdes , Barragán‐Huerta Blanca Estela
Published: February 2013

The process of extracting the astaxanthin oleoresin from pretreated Phaffia rhodozyma cells was optimised using a Box‐Behnken response surface design. Microwaving the cells at 105 W for 1 min followed by ethyl acetate extraction was the best pretreatment, and the optimal extraction conditions were 65 °C for 24 min using a solvent–solid ratio of 19:1. The order of the ability to disperse the astaxanthin oleoresin was propylene glycol> Tween 80 > Tween 20 > α‐cyclodextrin, β‐cyclodextrin. It was determined that the degradation of the colour of the water‐dispersible oleoresin followed a first‐order kinetics model. The greatest stability was observed at pH 4 and at the lowest temperature evaluated (40 °C). The thermal degradation of the pigment occurs in two steps, the first one from 0 to 1.5 h, with an EaI = 10.31 kJ mol−1, and the second one from 1.5 to 5 h, with an EaII = 30.06 kJ mol−1
Differentiation of post harvest date fruit varieties non‐destructively using FT‐NIR spectroscopy
Authors: Tavakolian, Mohammad S. S. , Silaghi, Florina A. , Fabbri, Angelo , Molari Giovanni , Giunchi Alessandro , Guarnieri Adriano
Published: February 2013

The world production of dates has more than doubled over the last two decades. Presently, the industrial sorting of dates is a difficult operation, affected by a high level of losses. As a consequence, the objective of this article is to study the variety discrimination capabilities of Fourier Transform‐Near Infrared (FT‐NIR) reflectance spectroscopy for post‐harvest sorting purposes. The same methodology was tested on six commercial date varieties named Estamaran, Kabkab, Mazafati, Piarom, Deglet nour and Zahedi. For each cultivar, 100 fruits were analysed using the FT‐NIR spectrometer, subsequently characterised by destructive measurements. A multivariate analysis of the FT‐NIR spectra appears a feasible tool for cultivar discrimination and even to estimate the soluble solid content (SSC) and dry matter (DM) of dates at their optimal harvesting conditions. FT‐NIR, as a non‐destructive techniques, could be a suitable way for on‐line screening of different dates varieties.
Chemical composition and nutritional value of raw and fried allis shad (Alosa alosa)
Authors: Pereira Teresa G. , Batista Irineu , Bandarra Narcisa M. , Ferreira Júlia , Fradinho Nuno , Afonso Fernando
Published: February 2013

The main objective of this study was to compare the proximate chemical composition and fatty acid profile of migrating allis shad (MS) and resident allis shad (RS) and to evaluate the nutritional value of fried migrating allis shad. No significant differences in the proximate chemical composition between males and females of each stock were obtained. However, MS fish had a significantly higher fat content than RS fish. The monounsaturated fatty acids group was the dominant in MS fish and oleic acid presented the highest percentage. Docosahexaenoic acid followed by eicosapentaenoic acid were the main PUFA in fish from both stocks. However, RS fish had higher total ω6 than MS fish due to its higher percentage of linoleic acid and arachidonic acid. Frying resulted in a significant reduction in water content and affected significantly the proximate chemical composition and the fatty acid profile, particularly the palmitic, oleic and linoleic acid.
Freshness and quality attributes of cold stored Atlantic bonito (Sarda sarda) gravad
Authors: Rzepka Magdalena , Özogul Fatih , Surówka Krzysztof , Michalczyk Magdalena
Published: February 2013

Quality and safety parameters of Atlantic bonito gravad during 42 days of storage at 7 ± 1 °C were analysed using monitoring sensory quality, microbial contamination, nucleotide degradation products, biogenic amines (BA), trimethylamine (TMA) and thiobarbituric acid reactive substances (TBARS). The shelf‐life of vacuum packed Atlantic bonito gravad was found to be 28 days. Total viable count (TVC) did not exceed 6 log CFU g−1. Malonodialdehyde (MDA) content did not surpass 10 mg kg−1. Nine biogenic amines were detected. Histamine level at the end of the storage was 355.3 mg kg−1. TMA increased from 53.9 to 619.1 mg kg−1. Among indicators based on the products of nucleotide degradation, the H value is best correlated with the sensory assessment. It can be concluded that the storage temperature of bonito gravad must be below 7 °C to prevent the threat to safety and quality posed by biogenic amines, especially histamine.
Why do firms train? Empirical evidence on the relationship between training and technological and organizational change
Authors: Neirotti Paolo , Paolucci Emilio
Published: February 2013

We explore the relationship between training and innovation using key insights from the resource‐based approach, organizational learning and labour studies. By using data from 304 large enterprises in Italy, the study highlights a twofold role of training in favouring technological and organizational changes. First, training plays a role in allowing the acquisition and the assimilation of new knowledge. Consequently, firms in which the provision of training is part of a bundle of high‐performance management practices are more likely to undertake technological and organizational changes and to develop new competencies internally. Second, training supports firms in the assimilation of technological and organizational changes. Consequently, firms that undertake these changes exhibit a superior participation rate for employees and greater time intensity of their training programmes. Firms' inclination to develop new competencies internally does not affect, however, the intensity of training, thereby suggesting that organizational learning processes do not start by a broad involvement of employees in formalized training programmes.
Competencies of specialised wound care nurses: a European Delphi study
Authors: Eskes Anne M , Maaskant Jolanda M , Holloway Samantha , van Dijk Nynke , Alves Paulo , Legemate Dink A , Ubbink Dirk T , Vermeulen Hester
Published: February 2013

Health care professionals responsible for patients with complex wounds need a particular level of expertise and education to ensure optimum wound care. However, uniform education for those working as wound care nurses is lacking. We aimed to reach consensus among experts from six European countries as to the competencies for specialised wound care nurses that meet international professional expectations and educational systems. Wound care experts including doctors, wound care nurses, lecturers, managers and head nurses were invited to contribute to an e‐Delphi study. They completed online questionnaires based on the Canadian Medical Education Directives for Specialists framework. Suggested competencies were rated on a 9‐point Likert scale. Consensus was defined as an agreement of at least 75% for each competence. Response rates ranged from 62% (round 1) to 86% (rounds 2 and 3). The experts reached consensus on 77 (80%) competences. Most competencies chosen belonged to the domain ‘scholar’ (n = 19), whereas few addressed those associated with being a ‘health advocate’ (n = 7). Competencies related to professional knowledge and expertise, ethical integrity and patient commitment were considered most important. This consensus on core competencies for specialised wound care nurses may help achieve a more uniform definition and education for specialised wound care nurses.
Three new Australian species of Trioza Foerster (Hemiptera: Triozidae) with a remarkable adaptation to oviposition on articulate branchlets of Allocasuarina (Casuarinaceae)
Authors: Taylor Gary S , Jennings John T , Purcell Matthew F , Austin Andrew D
Published: February 2013

Three new species of jumping plant bugs (Hemiptera: Psylloidea) are described from Allocasuarina (Casuarinaceae) from southern and eastern Australia. These are Trioza kentae Taylor sp. nov., T. percyae Taylor sp. nov. and T. tricornuta Taylor sp. nov. The female proctiger of two species, T. kentae Taylor sp. nov. and T. tricornuta Taylor sp. nov., has a three‐pronged apex, thought to be a remarkable morphological adaptation to assist with oviposition into the furrows of the branchlets or ‘articles’ of their host plant. It is postulated that the highly modified processes are used to ‘anchor’ the female proctiger during oviposition, where the medial prong positions the female ovipositor within a ‘furrow’ and the lateral processes straddle the ‘phyllichnia’ of the host plant ‘article’. In this way, eggs may be deposited within the furrow, thereby protected from desiccation and predation. In T. percyae Taylor sp. nov., the apex of the female proctiger is without any such structure. These are the first species of Trioza to be described from the Casuarinaceae.
A GIS‐based Vehicle Mobility Estimator for Operational Contexts
Authors: Hohmann Audrey , Grandjean Gilles , Mardhel Vincent , Schaefer Gilles , Desramaut Nicolas
Published: February 2013

A vehicle mobility estimator has been developed to produce decision aid maps for projecting civil or military forces on operational theatres. Based on the exploitation of classical geographical sources (e.g. digital elevation models, optical images, and vector databases) and thematic sources (e.g. climate, meteorological, pedological and land cover databases), the system computes speed maps for different kinds of vehicles moving both on‐road and off‐road. Such computations are realized through a ground‐vehicle interaction module that estimates the vehicle performance from experimental results, numerical simulations and empirical relationships. The system's architecture is built using a GIS interface that manages the data, the computation and the presentation layers. An operational version of this tool has been tested and validated on several operational theatres in France and in northern Africa. The results show good agreement between the predicted mobility performance of various vehicles and those observed on the field. A case study is presented to illustrate the mobility maps and demonstrate their relevance in the decision‐making chain depending on different climate contexts. A short application to itinerary optimization is presented as a promising future application.
Innovations in Practice: group work with children who are in care or who are adopted: lessons learnt
Authors: Ingley‐Cook Germaine , Dobel‐Ober David
Published: February 2013

Background

There is limited evidence on effective group interventions for looked‐after and adopted children. A specialist Children and Adolescent Mental Health Service (CAMHS) developed and evaluated a group intervention based on Mentalisation‐based therapy (MBT).

Method

Data was collected through semi‐structured interviews with all young people before and after the programme. Additional information was collected from the facilitators' reflective diaries. The study aimed to evaluate the impact and applicability of a Mentalisation‐based group programme on looked‐after and adopted children.

Results

Feedback from the young people indicated that the intervention had a positive impact on the young people.

Conclusions

Having a chance to meet other young people in similar circumstances, sharing experiences and making connections were the greatest benefits gained from the group.
Real‐Time Individual Predictions of Prostate Cancer Recurrence Using Joint Models
Authors: Taylor Jeremy M. G. , Park Yongseok , Ankerst Donna P. , Proust‐Lima Cecile , Williams Scott , Kestin Larry , Bae Kyoungwha , Pickles Tom , Sandler Howard
Published: February 2013

Patients who were previously treated for prostate cancer with radiation therapy are monitored at regular intervals using a laboratory test called Prostate Specific Antigen (PSA). If the value of the PSA test starts to rise, this is an indication that the prostate cancer is more likely to recur, and the patient may wish to initiate new treatments. Such patients could be helped in making medical decisions by an accurate estimate of the probability of recurrence of the cancer in the next few years. In this article, we describe the methodology for giving the probability of recurrence for a new patient, as implemented on a web‐based calculator. The methods use a joint longitudinal survival model. The model is developed on a training dataset of 2386 patients and tested on a dataset of 846 patients. Bayesian estimation methods are used with one Markov chain Monte Carlo (MCMC) algorithm developed for estimation of the parameters from the training dataset and a second quick MCMC developed for prediction of the risk of recurrence that uses the longitudinal PSA measures from a new patient.
Estimating Strain‐Specific and Overall Efficacy of Polyvalent Vaccines Against Recurrent Pathogens From a Cross‐Sectional Study
Authors: Auranen Kari , Rinta‐Kokko Hanna , Halloran M. Elizabeth
Published: February 2013

Evaluating vaccine efficacy for protection against colonization with bacterial pathogens is an area of growing interest. Colonization of the nasopharynx is an asymptomatic carrier state responsible for person‐to‐person transmission. It differs from most clinical outcomes in that it is common, recurrent, and observed only in its prevalent state. To estimate rates of acquisition and clearance of colonization requires repeated active sampling of the same individuals over time, an expensive and invasive undertaking. Motivated by feasibility constraints in efficacy trials with colonization endpoints, investigators have been estimating vaccine efficacy from cross‐sectional studies without principled methods. We present two examples of vaccine studies estimating vaccine efficacy from cross‐sectional data on nasopharyngeal colonization by Streptococcus pneumoniae (pneumococcus). This study presents a framework for defining and estimating strain‐specific and overall vaccine efficacy for susceptibility to acquisition of colonization () when there is a large number of strains with mutual interactions and recurrent dynamics of colonization. We develop estimators based on one observation of the current status per study subject, evaluate their robustness, and re‐analyze the two vaccine trials. Methodologically, the proposed estimators are closely related to case–control studies with prevalent cases, with appropriate consideration of the at‐risk time in choosing the controls.
An Application of Targeted Maximum Likelihood Estimation to the Meta‐Analysis of Safety Data
Authors: Gruber Susan , van der Laan Mark J.
Published: February 2013

Safety analysis to estimate the effect of a treatment on an adverse event poses a challenging statistical problem even in randomized controlled trials because these events are typically rare, so studies originally powered for efficacy are underpowered for safety outcomes. A meta‐analysis of data pooled across multiple studies may increase power, but missingness in the outcome or failed randomization can introduce bias. This article illustrates how targeted maximum likelihood estimation (TMLE) can be applied in a meta‐analysis to reduce bias in causal effect estimates, and compares performance with other estimators in the literature. A simulation study in which missingness in the outcome is at random or completely at random highlights the differences in estimators with respect to the potential gains in bias and efficiency. Risk difference, relative risk, and odds ratio of the effect of treatment on 30‐daymortality are estimated from data from eight randomized controlled trials. When an outcome event is rare there may be little opportunity to improve efficiency, and associations between covariates and the outcome may be hard to detect. TMLE attempts to exploit the available information to either meet or exceed the performance of a less sophisticated estimator.
Hierarchical Factor Models for Large Spatially Misaligned Data: A Low‐Rank Predictive Process Approach
Authors: Ren Qian , Banerjee Sudipto
Published: February 2013

This article deals with jointly modeling a large number of geographically referenced outcomes observed over a very large number of locations. We seek to capture associations among the variables as well as the strength of spatial association for each variable. In addition, we reckon with the common setting where not all the variables have been observed over all locations, which leads to spatial misalignment. Dimension reduction is needed in two aspects: (i) the length of the vector of outcomes, and (ii) the very large number of spatial locations. Latent variable (factor) models are usually used to address the former, although low‐rank spatial processes offer a rich and flexible modeling option for dealing with a large number of locations. We merge these two ideas to propose a class of hierarchical low‐rank spatial factor models. Our framework pursues stochastic selection of the latent factors without resorting to complex computational strategies (such as reversible jump algorithms) by utilizing certain identifiability characterizations for the spatial factor model. A Markov chain Monte Carlo algorithm is developed for estimation that also deals with the spatial misalignment problem. We recover the full posterior distribution of the missing values (along with model parameters) in a Bayesian predictive framework. Various additional modeling and implementation issues are discussed as well. We illustrate our methodology with simulation experiments and an environmental data set involving air pollutants in California.
The senior discount: biases against older career changers
Authors: Fritzsche Barbara , Marcus Justin
Published: February 2013

This study examined age discrimination in between‐ vs. within‐career job transitions. We expected that older workers transitioning into a new field would experience greater age discrimination than those who change jobs within the same field, particularly when amount of prior job experience is not made salient, and particularly when decision‐makers were highly prejudiced. Results suggested that younger job applicants received higher suitability ratings than older job applicants, and job applicants making a within‐career transition were rated higher than those making a between‐career transition. As hypothesized, older job applicants making between‐career transitions would receive the lowest ratings of suitability for hire when no information regarding experience was presented, and when decision‐makers were highly prejudiced. Implications for the aging workforce are discussed.
Palatal rugae and their role in forensic odontology
Authors: Jain Anoop , Chowdhary Ramesh
Published: February 2013

Establishing a person's identity can be a difficult task in cases of traffic accidents or in mass disaster situations. The records collected to identify a decedent should be accurate and totally inclusive of objective findings. When a victim has no teeth, information for use in personal identification based on methods available in forensic odontology is much more limited than in the case of dentate victims. Palatal rugae have been considered relevant for human identification due to its stability, which is equivalent to the fingerprint, in that it is unique for each ruga pattern. Palatal rugae appear to possess the features of an ideal forensic identification parameter, that is, uniqueness, postmortem resistance, and stability. The purpose of this article was to review the literature, in order to determine if there is enough evidence to establish the use of palatal rugae in dental identification.
Measuring inbreeding and inbreeding depression on pig growth from pedigree or SNP‐derived metrics
Authors: Silió L. , Rodríguez M.C. , Fernández A. , Barragán C. , Benítez R. , Óvilo C. , Fernández A.I.
Published: February 2013

Multilocus homozygosity, measured as the proportion of the autosomal genome in homozygous genotypes or in runs of homozygosity, was compared with the respective pedigree inbreeding coefficients in 64 Iberian pigs genotyped using the Porcine SNP60 Beadchip. Pigs were sampled from a set of experimental animals with a large inbreeding variation born in a closed strain with a completely recorded multi‐generation genealogy. Individual inbreeding coefficients calculated from pedigree were strongly correlated with the different SNP‐derived metrics of homozygosity (r = 0.814–0.919). However, unequal correlations between molecular and pedigree inbreeding were observed at chromosomal level being mainly dependent on the number of SNPs and on the correlation between heterozygosities measured across different loci. A panel of 192 SNPs of intermediate frequencies was selected for genotyping 322 piglets to test inbreeding depression on postweaning growth performance (daily gain and weight at 90 days). The negative effects on these traits of homozygosities calculated from the genotypes of 168 quality‐checked SNPs were similar to those of inbreeding coefficients. The results support that few hundreds of SNPs may be useful for measuring inbreeding and inbreeding depression, when the population structure or the mating system causes a large variance of inbreeding.
Discovering medical conditions associated with periodontitis using linked electronic health records
Authors: Boland Mary Regina , Hripcsak George , Albers David J. , Wei Ying , Wilcox Adam B. , Wei Jin , Li Jianhua , Lin Steven , Breene Michael , Myers Ronnie , Zimmerman John , Papapanou Panos N. , Weng Chunhua
Published: February 2013

Aim

To use linked electronic medical and dental records to discover associations between periodontitis and medical conditions independent of a priori hypotheses.

Materials and Methods

This case‐control study included 2475 patients who underwent dental treatment at the College of Dental Medicine at Columbia University and medical treatment at NewYork‐Presbyterian Hospital. Our cases are patients who received periodontal treatment and our controls are patients who received dental maintenance but no periodontal treatment. Chi‐square analysis was performed for medical treatment codes and logistic regression was used to adjust for confounders.

Results

Our method replicated several important periodontitis associations in a largely Hispanic population, including diabetes mellitus type I (OR = 1.6, 95% CI 1.30–1.99, p < 0.001) and type II (OR = 1.4, 95% CI 1.22–1.67, p < 0.001), hypertension (OR = 1.2, 95% CI 1.10–1.37, p < 0.001), hypercholesterolaemia (OR = 1.2, 95% CI 1.07–1.38, p = 0.004), hyperlipidaemia (OR = 1.2, 95% CI 1.06–1.43, p = 0.008) and conditions pertaining to pregnancy and childbirth (OR = 2.9, 95% CI: 1.32–7.21, p = 0.014). We also found a previously unreported association with benign prostatic hyperplasia (OR = 1.5, 95% CI 1.05–2.10, p = 0.026) after adjusting for age, gender, ethnicity, hypertension, diabetes, obesity, lipid and circulatory system conditions, alcohol and tobacco abuse.

Conclusions

This study contributes a high‐throughput method for associating periodontitis with systemic diseases using linked electronic records.
Effect of Age on Treatment Outcomes in Clostridium difficile Infection
Authors: Louie Thomas J. , Miller Mark A. , Crook Derrick W. , Lentnek Arnold , Bernard Louis , High Kevin P. , Shue Youe‐Kong , Gorbach Sherwood L.
Published: February 2013

Objectives

To determine the effect of advancing age on the clinical outcomes of Clostridium difficile (CDI) treatment.

Design

Regression modeling of results from two double‐blind randomized multicenter studies on the treatment of primary and first recurrent cases of CDI to examine for effects of age and study drug on outcomes of cure (resolution of diarrhea), recurrence within 4 weeks of completing successful therapy, and cure without recurrence.

Setting

Participants were randomized into studies in the United States, Canada, and Europe.

Participants

Nine hundred ninety‐nine individuals with toxin‐positive CDI were randomized to receive vancomycin (125 mg 4 times daily) or fidaxomicin (200 mg twice daily) for 10 days.

Measurements

The effect of advancing age in those aged 18 to 40 years and in 10‐year increments thereafter was examined.

Results

The model predicts a 17% lower clinical cure, 17% greater recurrence, and 13% lower sustained clinical response by advancing decade than in those younger than 40 (P < .01 each). Clinical cure was similar in the fidaxomicin and vancomycin treatment groups, although fidaxomicin was associated with a more than 50% lower relative risk for recurrence than vancomycin (P < .001). Multivariate regression modeling showed that risk factors accounting for poorer outcomes with advancing age include infection with the BI strain type, inpatient status, renal insufficiency, leukocytosis, hypoalbuminemia, and concomitant medication exposure.

Conclusion

Measurable and progressive deterioration in CDI treatment outcomes occurred with advancing age in those aged 40 and older, highlighting the need for prevention and treatment strategies. Fidaxomicin treatment was associated with a 60% lower risk of recurrence than vancomycin after adjusting for age, concomitant antibiotics, and C. difficile strain.
Analytical Propagation of Uncertainty in Life Cycle Assessment Using Matrix Formulation
Authors: Imbeault‐Tétreault Hugues , Jolliet Olivier , Deschênes Louise , Rosenbaum Ralph K.
Published: February 2013

Inventory data and characterization factors in life cycle assessment (LCA) contain considerable uncertainty. The most common method of parameter uncertainty propagation to the impact scores is Monte Carlo simulation, which remains a resource‐intensive option—probably one of the reasons why uncertainty assessment is not a regular step in LCA. An analytical approach based on Taylor series expansion constitutes an effective means to overcome the drawbacks of the Monte Carlo method. This project aimed to test the approach on a real case study, and the resulting analytical uncertainty was compared with Monte Carlo results. The sensitivity and contribution of input parameters to output uncertainty were also analytically calculated. This article outlines an uncertainty analysis of the comparison between two case study scenarios. We conclude that the analytical method provides a good approximation of the output uncertainty. Moreover, the sensitivity analysis reveals that the uncertainty of the most sensitive input parameters was not initially considered in the case study. The uncertainty analysis of the comparison of two scenarios is a useful means of highlighting the effects of correlation on uncertainty calculation. This article shows the importance of the analytical method in uncertainty calculation, which could lead to a more complete uncertainty analysis in LCA practice.
Insights into the oligomerization of CRMPs: crystal structure of human collapsin response mediator protein 5
Authors: Ponnusamy Rajesh , Lohkamp Bernhard
Published: February 2013

Collapsin response mediator protein‐5 (CRMP‐5) is the latest identified member of the CRMP cytosolic phosphoprotein family, which is crucial for neuronal development and repair. CRMPs exist as homo‐ and/or hetero‐tetramers in vivo and participate in signaling transduction, cytoskeleton rearrangements, and endocytosis. CRMP‐5 antagonizes many of the other CRMPs' functions either by directly interacting with them or by competing for their binding partners. We determined the crystal structures of a full length and a truncated version of human CRMP‐5, both of which form a homo‐tetramer similar to those observed in CRMP‐1 and CRMP‐2. However, solution studies indicate that CRMP‐5 and CRMP‐1 form weaker homo‐tetramers compared with CRMP‐2, and that divalent cations, Ca2+ and Mg2+, destabilize oligomers of CRMP‐5 and CRMP‐1, but promote CRMP‐2 oligomerization. On the basis of comparative analysis of the CRMP‐5 crystal structure, we identified residues that are crucial for determining the preference for hetero‐oligomer or homo‐oligomer formation. We also show that in spite of being the CRMP family member most closely related to dihydropyrimidinase, CRMP‐5 does not have any detectable amidohydrolase activity. The presented findings provide new detailed insights into the structure, oligomerization, and regulation of CRMPs.
If They Grow up: Exploring the Neighborhood Context of Adolescent and Young Adult Survival Expectations
Authors: Swisher Raymond R. , Warner Tara D.
Published: February 2013

Using data from the National Longitudinal Study of Adolescent Health, this study examines individual and neighborhood predictors of adolescent and young adult survival expectations—their confidence of surviving to age 35. Analyses revealed that within‐person increases in depression and violent perpetration decreased the odds of expecting to survive. Individuals who rated themselves in good health and received routine physical care had greater survival expectations. Consistent with documented health disparities, Black and Hispanic youth had lower survival expectations than did their White peers. Neighborhood poverty was linked to diminished survival expectations both within and between persons, with the between‐person association remaining significant controlling for mental and physical health, exposure to violence, own violence, and a wide range of sociodemographic factors.
Polyploidy and microsatellite variation in the relict tree Prunus lusitanica L.: how effective are refugia in preserving genotypic diversity of clonal taxa?
Authors: García‐Verdugo C. , Calleja J. A. , Vargas P. , Silva L. , Moreira O. , Pulido F.
Published: February 2013

Refugia are expected to preserve genetic variation of relict taxa, especially in polyploids, because high gene dosages could prevent genetic erosion in small isolated populations. However, other attributes linked to polyploidy, such as asexual reproduction, may strongly limit the levels of genetic variability in relict populations. Here, ploidy levels and patterns of genetic variation at nuclear microsatellite loci were analysed in Prunus lusitanica, a polyploid species with clonal reproduction that is considered a paradigmatic example of a Tertiary relict. Sampling in this study considered a total of 20 populations of three subspecies: mainland lusitanica (Iberian Peninsula and Morocco), and island azorica (Azores) and hixa (Canary Islands and Madeira). Flow cytometry results supported an octoploid genome for lusitanica and hixa, whereas a 16‐ploid level was inferred for azorica. Fixed heterozygosity of a few allele variants at most microsatellite loci resulted in levels of allelic diversity much lower than those expected for a high‐order polyploid. Islands as a whole did not contain higher levels of genetic variation (allelic or genotypic) than mainland refuges, but island populations displayed more private alleles and higher genotypic diversity in old volcanic areas. Patterns of microsatellite variation were compatible with the occurrence of clonal individuals in all but two island populations, and the incidence of clonality within populations negatively correlated with the estimated timing of colonization. Our results also suggest that gene flow has been very rare among populations, and thus population growth following founder events was apparently mediated by clonality rather than seed recruitment, especially in mainland areas. This study extends to clonal taxa the idea of oceanic islands as important refugia for biodiversity, since the conditions for generation and maintenance of clonal diversity (i.e. occasional events of sexual reproduction, mutation and/or seed immigration) appear to have been more frequent in these enclaves than in mainland areas.