bluuebunny/crossref_metadata_2025_split huggingface dataset:
Atomic Bose fluids in optical lattices
Authors: Gemelke Nathan , Chin Cheng 
Published: March 2015

Abstract
The physics of bosonic atoms in optical lattices is described. Starting from the basic experimental tools available to create such systems, the chapter introduces a simple model (known as the Bose—Hubbard model) for such a system. A mean-field type picture is developed to determine the basic character of the superfluid and Mott-insulating phases, and the physical conditions under which each should arise. A number of experimental methods are outlined to detect the properties of the gas. The fact that two thermodynamic ground states exist at zero temperature with different types of order implies the existence of a quantum phase transition. The behavior of the gas near this transition is described using an entirely different framework—quantum criticality—formed around the concepts of scaling symmetry and the renormalization group.
Observation influence diagnostic of a data assimilation system
Authors: Cardinali C. 
Published: March 2015

Abstract
This chapter presents the concept of the influence matrix. Because of the cost and the possible redundancy of observations, particularly in numerical weather prediction systems, quantifying the influence of individual observations on data assimilation analysis is increasingly important. This chapter describes how the influence matrix is used to examine the influence of individual data on the analysis, the analysis change that would occur by leaving one observation out, and the effective information content (degrees of freedom for the signal) in any subset of the analysed data. A toy model is introduced to illustrate how the observation influence depends on the data assimilation covariance matrices. It is shown, in particular, that this influence strongly depends on the relative nature of the background and observation error covariance matrices.
Errors. A posteriori diagnostics
Authors: Talagrand O. 
Published: March 2015

AbstractThis chapter discusses three questions concerning the implementation and validation of assimilation algorithms. Objective estimation of the quality of the results of an assimilation system can be done only through comparison against independent data. Objective estimation of the statistics of the errors in the data is discussed in the context of best linear unbiased estimation, which underlies both the Kalman filter and variational assimilation. It is shown that those statistics remain totally undetermined in the absence of independent hypotheses, which cannot be objectively validated just through processing of the data. The most that can be done is to check consistency between the statistics of the innovation, as a priori implied by the specification of the data error and as a posteriori observed. Optimality of a least variance estimation procedure can be objectively evaluated against independent data using the fact that the estimation error must be statistically uncorrelated with the innovation.
Short-range error statistics in an ensemble Kalman filter
Authors: Houtekamer P. 
Published: March 2015

Abstract
This chapter deals with short-range error statistics in the context of the ensemble Kalman filter (EnKF). To arrive at an optimal data-assimilation system, a good description of the uncertainty in the background field is needed. Historically, different approaches, with a solid comparison against either a ground truth or observations, have been used to obtain limited descriptions. The first category includes observation system simulation experiments (OSSEs), while the second includes methods based on statistical analysis of innovations. The EnKF is a relatively new method that simulates the effect of known sources of error to arrive at a Monte Carlo estimate of flow-dependent background error statistics. It is necessary to validate the ensemble statistics–in part by comparison with results from established methods–to identify areas of improvement for the EnKF. This chapter first summarizes existing methods and then studies the properties of a research version of the Canadian global EnKF.
Structure and responsiveness
Authors: Grindrod CBE Peter 
Published: March 2015

Abstract
This chapter considers what dynamical models might tell about what has and has not been observed. This includes dynamics of opinions and social contacts which are time dependent and fully coupled. It considers Turing instability as a mechanism for generating patchiness in population models with both activator and inhibitory mechanisms as well as homophily. It considers how external events may drive avalanches of activity on peer-to-peer networks and also the possible exploitation of topic/interest-defined subsets of networks. It presents applications of Twitter data analysis in real time situations and to strategic decision-making in marketing.
Models of electroweak symmetry breaking
Authors: Pomarol Alex 
Published: March 2015

Abstract
This chapter present models of electroweak symmetry breaking arising from strongly interacting sectors, including both Higgsless models and mechanisms involving a composite Higgs. These scenarios have also been investigated in the framework of five-dimensional warped models that, according to the AdS/CFT correspondence, have a four-dimensional holographic interpretation in terms of strongly coupled field theories. We explore the implications of these models at the LHC.
AdS crunches, CFT falls, and cosmological complexity
Authors: José Luis Barbón , Eliezer Rabinovici 
Published: March 2015

Abstract
This chapter discusses the holographic description of crunching AdS cosmologies. Crunching FRW models with hyperbolic spatial sections are dual to semiclassical condensates in deformed de Sitter (dS) CFTs. dS-invariant condensates with a sharply defined energy scale are induced by effective negative-definite relevant or marginal operators, which may or may not destabilize the CFT. This result is obtained by explicitly constructing a “complementarity map” for this model, given by a conformal transformation of the dS CFT into a static time-frame, which reveals the crunch as an infinite potential-energy fall in finite time. Quite generically, the crunch is associated with a finite-mass black hole if the dS O(d, 1) invariance is an accidental IR symmetry, broken to U(1) × O(d) in the UV. Any such regularization cuts off the eternity of dS spacetime. Equivalently, the dimension of the Hilbert space propagating into the crunch is finite only when dS is not eternal.
Predicting protein interface residues using easily accessible on-line resources
Authors: Maheshwari Surabhi , Brylinski Michal 
Published: March 2015

AbstractIt has been more than a decade since the completion of the Human Genome Project that provided us with a complete list of human proteins. The next obvious task is to figure out how various parts interact with each other. On that account, we review 10 methods for protein interface prediction, which are freely available as web servers. In addition, we comparatively evaluate their performance on a common data set comprising different quality target structures. We find that using experimental structures and high-quality homology models, structure-based methods outperform those using only protein sequences, with global template-based approaches providing the best performance. For moderate-quality models, sequence-based methods often perform better than those structure-based techniques that rely on fine atomic details. We note that post-processing protocols implemented in several methods quantitatively improve the results only for experimental structures, suggesting that these procedures should be tuned up for computer-generated models. Finally, we anticipate that advanced meta-prediction protocols are likely to enhance interface residue prediction. Notwithstanding further improvements, easily accessible web servers already provide the scientific community with convenient resources for the identification of protein–protein interaction sites.
Two-group comparisons of zero-inflated intensity values: the choice of test statistic matters
Authors: Gleiss Andreas , Dakna Mohammed , Mischak Harald , Heinze Georg 
Published: March 2015

Abstract
Motivation: A special characteristic of data from molecular biology is the frequent occurrence of zero intensity values which can arise either by true absence of a compound or by a signal that is below a technical limit of detection.
Results: While so-called two-part tests compare mixture distributions between groups, one-part tests treat the zero-inflated distributions as left-censored. The left-inflated mixture model combines these two approaches. Both types of distributional assumptions and combinations of both are considered in a simulation study to compare power and estimation of log fold change. We discuss issues of application using an example from peptidomics.
The considered tests generally perform best in scenarios satisfying their respective distributional assumptions. In the absence of distributional assumptions, the two-part Wilcoxon test or the empirical likelihood ratio test is recommended. Assuming a log-normal subdistribution the left-inflated mixture model provides estimates for the proportions of the two considered types of zero intensities.
Availability: R code is available at http://cemsiis.meduniwien.ac.at/en/kb/science-research/software/
Contact: georg.heinze@meduniwien.ac.at
Supplementary information: Supplementary data are available at Bioinformatics online.
Scoliosis is a Risk Factor for Gastroesophageal Reflux Disease in Adult Spinal Deformity
Authors: Hosogane Naobumi , Watanabe Kota , Yagi Mitsuru , Kaneko Shinjiro , Toyama Yoshiaki , Matsumoto Morio 
Published: March 2015

Study Design:
A prospective observational study.

Objective:
To evaluate whether scoliosis is a risk factor for gastroesophageal reflux disease (GERD) in elderly patients.

Summary of Background Data:
Sagittal spinal deformities are reported to cause GERD, but its association with spinal deformity in the coronal plane is not well studied.

Methods:
We examined 190 patients with spinal disorders (mean age 70.6±8.6 y) who underwent standing whole-spine x-rays in the coronal and sagittal planes. GERD symptoms were assessed by Quest score, with a cutoff of 6 points. The relationship between GERD symptoms and radiographic parameters was evaluated. Right convex coronal curves were given negative values, and left convex curves positive values. Degenerative scoliosis was defined when the thoracolumbar/lumbar Cobb angle had an absolute value >10 degrees. Risk factors for GERD were evaluated with univariate and multivariate logistic regression analyses.

Results:
Of the patients, 126 had degenerative scoliosis at the thoracolumbar/lumbar spine (42 with right and 84 with left convex curve), and 59 had GERD. Multivariate logistic regression analysis revealed that the lumbar Cobb angle was significantly associated with GERD (P<0.05, odds ratio=1.021). When patients were categorized by Cobb angle of the lumbar curve (<−30 degrees, large right convex curve; −30 to +30 degrees, small curve; or >+30 degrees, large left convex curve), a large left convex curve was strongly associated with GERD (P<0.05, odds ratio=10.925).

Conclusions:
Left thoracolumbar/lumbar curve was a significant risk factor for GERD, and risk increased with a curve >30 degrees. Organ disorders such as GERD should be considered when treating elderly patients with degenerative scoliosis.
Accuracy of Iliac Screws Insertion in Adult Spinal Deformity Surgery
Authors: Banno Tomohiro , Ohishi Tsuyoshi , Hasegawa Tomohiko , Yamato Yu , Kobayashi Sho , Togawa Daisuke , Yasuda Tatsuya , Matsuyama Yukihiro 
Published: March 2015

Study design:
Retrospective study.

Objective:
To investigate the accuracy of freehand iliac screw insertion and to determine how this can be performed safely.

Background and Methods:
Seventy-seven adult scoliosis patients with an average age of 70.1 years who underwent spinal deformity surgery with spinopelvic fixation using bilateral iliac screws were enrolled. Penetration of the iliac table was assessed using postoperative computed tomography. Screw penetration of the iliac table or screw insertion from the sacroiliac joint was considered misplacement. Screw positioning was classified as the screw being in the proper position (group C), the screw penetrating the outer table (group O), and the screw penetrating the inner table (group I). The iliac opening angle and the distance between the posterior superior iliac spines (PSISs) were measured using preoperative computed tomography. The angle between the sacral slope and the iliac screw, termed as the sagittal screw angle, was measured using postoperative lateral lumbar radiography.

Results:
Of the 154 iliac screws in 77 patients, 14 screws in 12 patients penetrated the outer table and 12 screws in 11 patients penetrated the inner table. The total proportion of misplacement was 18.8%, although there were no major complications. With regard to iliac morphology, the iliac opening angle was 24.2±4.3 degrees and the distance between the PSISs was 90.6±7.7 mm. The distance between the PSISs correlated negatively with the iliac opening angle. The iliac opening angle was smaller in group O than in group C (P<0.05). The sagittal screw angle in group I was smaller than that in group C (P<0.01).

Conclusions:
Screw penetration of the outer iliac table possibly occurred in patients with a narrow iliac opening angle. Screw penetration of the inner table occurred when the screw was inserted more cranially than the sacral slope. Therefore, the iliac screw should be inserted approximately parallel to the sacral slope.
The validation of an assessment centre in Asia
Authors: Furnham Adrian , Toh Shi Min 
Published: March 2015

Purpose
– The purpose of this paper is to attempt to assess the validity of an assessment centre (AC) designed for the promotional purposes of police officers, conducted in the Asian context.

Design/methodology/approach
– The study included 128 police officers of whom criterion data was available for 49 officers. They all took part in an established AC.

Findings
– The overall AC rating was significantly related to both overall training performance (r=0.58, p<0.01) and estimated leadership potential data (r=0.25, p<0.05), both collected two years subsequent to the promotion process. Analyses further supported the situational specificity of the AC design; with particular exercises and performance traits underlying the predictive value of the AC. It also showed the incremental validity of the AC methodology over and above personality measures.

Social implications
– The study supports the continual usage of the AC methodology across cultural contexts.

Originality/value
– As far as we know this research has not been done in this part of the world.
Why do firms adopt employee share ownership? Bundling ESO and direct involvement for developing human capital investments
Authors: Guery Loris 
Published: March 2015

Purpose– The purpose of this paper is to examine the relationship between employee share ownership (ESO) and employer-provided training. To be more specific, as both ESO and involvement practices can contribute to developing human capital, the paper addresses the question of whether they are substitutes or complements in the relationship with training.Design/methodology/approach– The theoretical hypotheses are tested using the French nationally representative establishment-level survey, REPONSE, which is similar to the British WERS. The sample consists of 1,523 establishments.Findings– The results are consistent with studies conducted elsewhere (e.g. in the UK) and provide novel findings, thereby suggesting a complementarity between ESO and involvement practices with bundles of practices becoming increasingly more complex as training expenditures increase.Research limitations/implications– To provide further insights, future research that uses more precise information regarding ESO plans is needed.Practical implications– Results can provide HR managers with valuable information regarding the organisational characteristics necessary to ensure a fertile ground for their training expenses.Originality/value– The paper reflects a growing awareness that human capital development and share ownership plans may be related and that this relationship might be a more compelling explanation for share ownership plans than the standard agency theory. The contribution of ESO plans to the development of employee competencies may be at least as important as their possible effects on employee motivation and effort.
Framework for the use of landscaping waste for alternative energy generation
Authors: Heinicke Matthias 
Published: March 2015

Purpose
– Against the background of alternative sources for feeding biogas plants, this paper aims to consider a utilization of landscaping waste as alternative to common crops.

Design/methodology/approach
– In consideration of survey data, a robust framework is proposed based on characterizations of source and sink to meet the requirements of both sides reliably. Depending on available data and further surveys, a level of detail approach of a biomass supply chain is conducted in this regard.

Findings
– In this context, different types of landscaping waste suitable for both biogas generation and incineration were defined. With respect to the sporadically minor quantities of landscaping waste, minor capacity load in terms of transportation is one crucial factor within an entire concept of logistics.

Practical implications
– Due to the arising cost function, possibilities and needs of utilizing landscaping waste for alternative energy generation in biogas plants and incineration plants are drawn.

Originality/value
– Moreover, economic and technological challenges concerning a utilization of landscaping waste in biogas plants are systematically revealed. Thus, technological processes in biogas plants were considered from a managerial point of view. The characteristics of rotting biomass in terms of its shelf life are considered additionally to ensure the required quality of input material particularly for the process of biogas generation.
Oil price shocks and exchange rate in Nigeria
Authors: Babatunde Musibau Adetunji 
Published: March 2015

Purpose– This study aims to examine the relationship between the oil price and the exchange rate for Nigeria between January 1997 and December 2012. Previous empirical studies revealed an ambiguous relationship between crude oil prices and exchange rates, a reason for exploring the differential effects of positive and negative oil price shocks on the exchange rate.Design/methodology/approach– Time series and structural analysis were used.Findings– The findings indicate different responses for the exchange rate with respect to positive and negative oil price shocks. Positive oil price shocks were found to depreciate the exchange rate, whereas negative oil price shocks appreciate the exchange rate. In addition, the asymmetric effects of positive and negative oil price shocks on the real exchange rate were not supported by the statistical evidences. The empirical results were robust to different specifications.Originality/value– To the best of the authors’ knowledge, this is the first paper to assess the differential impact of positive and negative oil price shocks and the role of oil prices in predicting the exchange rate over long horizons in Nigeria.
A policy-based middleware for context-aware pervasive computing
Authors: El Khaddar Mehdia Ajana , Chraibi Mhammed , Harroud Hamid , Boulmalf Mohammed , Elkoutbi Mohammed , Maach Abdelilah 
Published: March 2015

Purpose
– This paper aims to demonstrate that a policy-based middleware solution which facilitates the development of context-aware applications and the integration of the heterogeneous devices should be provided for ubiquitous computing environments. Ubiquitous computing targets the provision of seamless services and applications by providing an environment that involves a variety of devices having different capabilities. These applications help transforming the physical spaces into computationally active and smart environments. The design of applications in these environments needs to consider the heterogeneous devices, applications preferences and rapidly changing contexts. The applications, therefore, need to be context-aware so that they can adapt to different situations in real-time.

Design/methodology/approach
– In this paper, we argue that a policy-based middleware solution that facilitates the development of context-aware applications and the integration of the heterogeneous devices should be provided for ubiquitous computing environments. The middleware allows applications to track items and acquire contextual information about them easily, reason about this information captured using different logics and then adapt to changing contexts. A key issue in these environments is to allow heterogeneous applications to express their business rules once, and get the preferred data once they are captured by the middleware without any intervention from the application side.

Findings
– Our middleware tackles this problem by using policies to define the different applications’ rules and preferences. These policies can specify rules about the middleware services to be used, type of data captured, devices used, user roles, context information and any other type of conditions.

Originality/value
– In this paper, we propose the design of a flexible and performant ubiquitous computing, and context-aware middleware called FlexRFID along with its evaluation results.
Resilience in the context of Italian micro and small wineries: an empirical study
Authors: Duarte Alonso Abel , Bressan Alessandro 
Published: March 2015

Purpose
– The purpose of this paper is to study resilience among micro and small wineries. While the subject of organisational resilience has drawn the attention or numerous researchers, there is an argument that limited empirical evidence exist to support different theoretical constructs in regards to resilience. Thus, the paper addresses a knowledge gap.

Design/methodology/approach
– A questionnaire was designed to investigate strategies that can help businesses to become more resilient to contemporary challenges. A total of 273 owners and managers of Italian wineries participated in the study.

Findings
– Increasing costs, institutional barriers and the effects of the economic crisis on consumers’ wine purchases are perceived as most serious challenges. One fundamental impact is respondents’ loss of trust in institutions. Alternatives such as diversifying, knowledge of foreign languages and educational activities emerged as crucial to improve wineries’ performance, and therefore build their resilience.

Practical implications
– These findings highlight the vital role of institutions in developing supporting strategies to nurture an entrepreneurial culture among owners and managers of a very important group of businesses.

Originality/value
– By empirically investigating ways to achieve resilience among businesses of a traditional European sector, the study addresses a knowledge gap identified in contemporary research. The study also contributes to the development of the theory of resilience, for instance, by considering the literature on the theory of resilience, considering and adopting factors affecting micro and small enterprises’ resilience and identifying some of these factors in the context of micro and small wine enterprises.