bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative study of poly(L‐lactide) nanocomposites with organic montmorillonite and carbon nanotubes
Authors: Chen Hai‐ming , Chen Jie , Shao Li‐na , Yang Jing‐hui , Huang Ting , Zhang Nan , Wang Yong 
Published: October 2012

AbstractOrganic montmorillonite (OMMT) and the one‐dimensional functionalized multiwalled carbon nanotubes (FMWCNTs) were introduced into poly(L‐lactide) (PLLA) to prepare PLLA/OMMT and PLLA/FMWCNT nanocomposites, respectively. The effects of nanofillers on melt crystallization and cold crystallization of PLLA were comparatively investigated by using polarized optical microcopy, differential scanning calorimetry and wide angle X‐ray diffraction. The results show that FMWCNTs exhibit higher nucleation efficiency for the melt crystallization of PLLA, whereas OMMT is the better one for the cold crystallization of PLLA. Rheological properties show that both OMMT and FMWCNTs at relatively higher concentrations can form the percolated network structure in the PLLA matrix, however, the latter nanocomposites exhibit relatively denser or more compact percolated networks. The difference of the networks between OMMT and FMWCNTs is suggested to be the main reason for the different cold crystallization behaviors observed in the PLLA/OMMT and PLLA/FMWCNT nanocomposites. The dynamic mechanical analysis measurements show that OMMT is the better one to improve the stiffness of the nanocomposites in the present work. The thermogravimetric analysis measurements show that FMWCNTs have higher efficiency in improving the thermal stability of PLLA compared with OMMT. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013
Beware of the black swan: The limitations of risk analysis for predicting the extreme impact of rare process safety incidents
Authors: Murphy John F. , Conner Jim 
Published: October 2012

AbstractThis article will discuss the concept of the black swan, the extreme impact of rare and unpredictable events, as applied to chemical process risk assessment. Lessons learned from black swan events of the past and the applicability of these lessons to the design and operations of existing and new chemical processing facilities will be discussed. The limitations of layer of protection analysis (LOPA) and other risk analysis tools in predicting black swan events will be examined. The discussion on the limitations of risk analysis will include examples of hazards scenarios where risk analysis tools such as LOPA may not be appropriate. © 2012 American Institute of Chemical Engineers Process Saf Prog, 2012.
Study on performance‐based safety spacing between ultra‐large oil tanks
Authors: Yifei Meng , Dongfeng Zhao , Yi Liu , Wendong Wang 
Published: October 2012

AbstractAt present, storage capacities of single tank and tank farm have been greatly increasing. This change poses a real challenge for the applicability of current design standards. This article focuses on the applicability of safety spacing between tanks, which is one of the most important parameters of tank farm safety design. Taking PHAST and FDS as main research tools, the consequences of representative accidental scenarios were evaluated for different sizes of oil tanks to study the safety performance change caused by the increase of capability. The research results show that, when current standards are used to design the safety spacing between tanks, the safety performance increases as the capability increases. Considering the high property density, it is suggested that a higher safety performance objective has to be chosen when designing the safety spacing for ultra‐large oil tanks. © 2012 American Institute of Chemical Engineers Process Saf Prog, 2012.
On the stability issues of switched singular time‐delay systems with slow switching based on average dwell‐time
Authors: Zamani Iman , Shafiee Masoud 
Published: October 2012

SUMMARYThe issue of exponential stability analysis of continuous‐time switched singular systems consisting of a family of stable and unstable subsystems with time‐varying delay is investigated in this paper. It is very difficult to analyze the stability of such systems because of the existence of time‐delay and unstable subsystems. In this regard, on the basis of the free‐weighting matrix approach, by constructing the new Lyapunov‐like Krasovskii functional, and using the average dwell‐time approach, delay‐dependent sufficient conditions are derived and formulated in terms of LMIs to check the exponential stability of such systems. This paper also highlights the relationship between the average dwell‐time of the switched singular time‐delay system, its stability, exponential convergence rate of differential states, and algebraic states. Finally, a numerical example is given to confirm the analytical results and illustrate the effectiveness of the proposed strategy. Copyright © 2012 John Wiley & Sons, Ltd.
The Psychology and Practice of Youth‐Adult Partnership: Bridging Generations for Youth Development and Community Change
Authors: Zeldin Shepherd , Christens Brian D. , Powers Jane L. 
Published: October 2012

AbstractYouth‐adult partnership (Y‐AP) has become a phenomenon of interest to scholars and practitioners. Despite the potential of Y‐AP to promote positive youth development, increase civic engagement, and support community change, the practice remains unfamiliar to many. Although research has increased over the past decade, the construct remains vague with an insufficient grounding in developmental theory and community practice. This article seeks to address these gaps by synthesizing data and insights from the historical foundations of Y‐AP, community based research, and case study. We propose Y‐AP as a unifying concept, distinct from other forms of youth‐adult relationships, with four core elements: authentic decision making, natural mentors, reciprocity, and community connectedness. We conclude that Y‐AP functions as an active ingredient and fundamental practice for positive youth development and civic engagement. Directions for future research are offered.
Oil Production from De‐shelled Aquilaria crassna Seeds Using Supercritical Carbon Dioxide Extraction
Authors: Chen Chao‐Rui , Cheng Yang‐Jung , Shieh Chwen‐Jen , Hsiang Daina , Chang Chieh‐Ming J. 
Published: October 2012

AbstractThis study examined the use of supercritical carbon dioxide (SC‐CO2) in the extraction of triglycerides from de‐shelled Aquilaria crassna seeds. A central composite response surface methodology was employed to evaluate the effects of pressure, temperature and solvent‐to‐solid ratio (SSR) on total yield (TY), concentration of triglycerides (CTG) and recovery of triglycerides (RTG). For this experimental design, pressures that ranged from 250 to 350 bar, temperatures that ranged from 313 to 333 K and SSR that ranged from 80 to 120 were investigated for the SC‐CO2 extractions of 15 g of powdered de‐shelled A. crassna seeds at a CO2 flow rate of 25 mL/min under the supercritical phase. The values of TY, CTG and RTG achieved were 36.89 %, 709.5 mg/g and 95.4 %, respectively, under the conditions of a pressure of 340 bar, a temperature of 333 K and an SSR of 115 obtained from the quadratic fitting models.
Ageostrophic instability in a rotating stratified interior jet
Authors: Ménesguen Claire , McWilliams J. C. , Molemaker M. J. 
Published: October 2012

AbstractOceanic large- and meso-scale flows are nearly balanced in forces between Earth’s rotation and density stratification effects (i.e. geostrophic, hydrostatic balance associated with small Rossby and Froude numbers). In this regime advective cross-scale interactions mostly drive energy toward larger scales (i.e. inverse cascade). However, viscous energy dissipation occurs at small scales. So how does the energy reservoir at larger scales leak toward small-scale dissipation to arrive at climate equilibrium? Here we solve the linear instability problem of a balanced flow in a rotating and continuously stratified fluid far away from any boundaries (i.e. an interior jet). The basic flow is unstable not only to geostrophic baroclinic and barotropic instabilities, but also to ageostrophic instabilities, leading to the growth of small-scale motions that we hypothesize are less constrained by geostrophic cascade behaviours in a nonlinear regime and thus could escape from the inverse energy cascade. This instability is investigated in the parameter regime of moderate Rossby and Froude numbers, below the well-known regimes of gravitational, centrifugal, and Kelvin–Helmholtz instability. The ageostrophic instability modes arise with increasing Rossby number through a near-degeneracy of two unstable modes with coincident phase speeds. The near-degeneracy occurs in the neighbourhood of an identified criterion for the non-integrability of the ‘isentropic balance equations’ (namely $A\ensuremath{-} S= 0$ with $A$ the absolute vertical vorticity and $S$ the horizontal strain rate associated with the basic flow), beyond which development of an unbalanced component of the flow is expected. These modes extract energy from the basic state with large vertical Reynolds stress work (unlike geostrophic instabilities) and act locally to modify the basic flow by reducing the isopycnal Ertel potential vorticity gradient near both its zero surface and its critical surface (phase speed equal to basic flow speed).
Modeling the Cross Section of Stock Returns: A Model Pooling Approach
Authors: O’Doherty Michael , Savin N. E. , Tiwari Ashish 
Published: October 2012

AbstractModel selection (i.e., the choice of an asset pricing model to the exclusion of competing models) is an inherently misguided strategy when the true model is unavailable to the researcher. This paper illustrates the advantages of a model pooling approach in characterizing the cross section of stock returns. The optimal pool combines models using the log predictive score criterion, a measure of the out-of-sample performance of each model, and consistently outperforms the best individual model. The benefits to model pooling are most pronounced during periods of economic stress, and it is a valuable tool for asset allocation decisions.
LEEM: A new empirical model of radiation‐belt electrons in the low‐Earth‐orbit region
Authors: Chen Yue , Reeves Geoffrey , Friedel Reiner H. W. , Thomsen Michelle F. , Looper Mark , Evans David , Sauvaud Jean‐Andre 
Published: October 2012

A new empirical model of radiation‐belt electrons in the low‐Earth‐orbit region has been developed based upon decade‐long in situ observations from several low‐altitude‐orbiting satellites. This model—LEEM—aims to provide the electron environment conditions that a satellite would encounter in a given low Earth orbit. This model presents electron flux values for five energy ranges (0.03–2.5 MeV, 0.1–2.5 MeV, 0.3–2.5 MeV, 1.5–6 MeV, and 2.5–14 MeV) within the space below an altitude of ∼600 km. Compared to the de‐facto standard empirical model of AE‐8, this model not only has a better data coverage in this specific region, but also can provide statistical information on flux levels such as worst cases and occurrence percentiles instead of solely mean values. The comparison indicates that the AE‐8 model not only highly overpredicts the fluxes in the inner belt region in most cases, especially for the MeV electrons, which cannot be accounted for by the widely quoted error factor of 2 for AE‐8, but also is unable to reflect the observed orders of magnitude variations in electron intensities. The LEEM model is carefully validated with both in‐sample and out‐of‐sample tests. The characteristic electron environments along the International Space Station track and other virtual orbits are given as examples and as a demonstration of the use of the model.
Issues and possible intervention strategies relating to early weaning of piglets.
Authors: Amadori M. , Razzuoli E. , Nassuato C. 
Published: October 2012

Abstract
Early weaning of farmed pigs before 25 days of age is a complex multi-factor stressor, often leading to health and welfare issues. The most obvious and crucial feature is that many piglets do not consume food in this period. On this basis, the final stressing impact is derived from a combination of physical, nutritional, immunological and emotional components. On the whole, there is strong evidence that a reduction in the pigs' weaning age can lead to increased adaptation difficulties in terms of behavioural, neuroendocrine and immune responses, as also observed by means of clinical immunology and chemistry analyses. This is the argument underlying the recommended minimum age of 28 days at weaning in EU Directive 2001/93/EC. Inflammatory, stress and innate immune responses sustain the coping efforts of piglets at weaning. Some responses are weaning-specific, whereas others reflect the related social stress of regrouping (mixing) and separation from the sow. An innate immune response to tissue damage at weaning (shorter, atrophic villi and larger, deeper crypts) and relevant control mechanisms are likely to be of paramount importance. In this respect, type I (α/β) interferons (IFNs) were shown to play a major regulatory role of the inflammatory response at weaning. Also, a low-dose, oral IFN-α treatment was shown to sustain the coping efforts of piglets. These results are of some importance in view of a global assessment of food safety 'from farm to fork', and of the related need to reduce the extensive, diarrhoea-related use of drug-supplemented feeds after weaning.
The effects of forest fragmentation on species richness on the Obudu Plateau, south‐eastern Nigeria
Authors: Dami Filibus Danjuma , Mwansat Georgina Samuel , Manu Shiiwa A. 
Published: October 2012

AbstractThis study examines how fragmentation through changes in patch size and increasing distances between forest patches affects bird species richness. Numbers of bird species were higher in large forest patches and decrease with decreasing patch size. Bird species richness also decreased with increased isolation of forest patches. Suitable trees should be planted in the gaps between the forests that will create wildlife corridors to maintain connectivity.
Reciprocal modulation of internal and external factors determines individual movements
Authors: Martin Jodie , van Moorter Bram , Revilla Eloy , Blanchard Pierrick , Dray Stéphane , Quenette Pierre‐Yves , Allainé Dominique , Swenson Jon E. 
Published: October 2012

Summary

Movement is fundamental to individual and population dynamics, as it allows individuals to meet their basic requirements. Although movement patterns reflect interactions between internal and external factors, only few studies have examined the effects of these factors on movement simultaneously, and they generally focused on particular biological contexts (e.g. dispersal, foraging).
However, the relative importance of these factors in driving individual routine movements might reflect a species' potential flexibility to cope with landscape changes and therefore buffer their potential impact on fitness.
We used data from GPS collars on Scandinavian brown bears to investigate the relative role of these factors, as well as an additional factor (period of the year) on routine movements at two spatial scales (hourly and daily relocations).
As expected, internal factors played a major role in driving movement, compared to external factors at both scales, but its relative importance was greater at a finer scale. In particular, the interaction between reproductive status and period of the year was one of the most influential variables, females being constrained by the movement capacity of their cubs in the first periods of the year. The effect of human disturbance on movement was also greater for females with cubs than for lone females.
This study showed how reciprocal modulation of internal and external factors is shaping space use of brown bears. We stress that these factors should be studied simultaneously to avoid the risk of obtaining context‐dependent inferences. Moreover, the study of their relative contribution is also highly relevant in the context of multiple‐use landscapes, as human activities generally affect the landscape more than they affect the internal states of an individual. Species or individuals with important internal constraints should be less responsive to changes in their environment as they have less freedom from internal constraints and should thus be more sensitive to human alteration of the landscape, as shown for females with cubs in this study.
Impact of aluminium stress on oxalate and other metabolites inRumex obtusifolius
Authors: MIYAGI A , UCHIMIYA M , KAWAI‐YAMADA M , UCHIMIYA H 
Published: October 2012

SummaryTo understand alterations of oxalate and other metabolite levels induced by aluminium ion (Al3+) stress inRumexplants, we measured the metabolites inR. obtusifoliususing the capillary electrophoresis–mass spectrometry. Oxalate and its precursors (isocitrate and citrate) accumulated in leaves ofR. obtusifoliusafter the Al3+treatment at pH 4.5. Such increase was not observed under the acidic condition (pH 4.5) without Al3+. Principal component analysis showed organ‐specific changes in metabolite levels inR. obtusifoliusby the Al3+treatment. Highly positive correlations between oxalate and its precursors were revealed by hierarchical clustering and correlation analyses. An increase in oxalate content was consistently observed for threeRumexspecies (R. obtusifolius, R. crispusandR. japonicus) grown in the presence of Al3+. On the other hand, multivariate analyses revealed the differential alterations of other metabolite levels betweenR. obtusifoliusand the other twoRumexspecies.
Perspectives in ablation of arrhythmias in children and patients with congenital heart disease
Authors: Pflaumer Andreas 
Published: October 2012

AbstractAlthough most arrhythmias in children have a benign outcome, recurrent arrhythmic events have a significant impact on quality of life. Electrophysiology studies with ablation have good short‐term success and an acceptably low complication rate. The long‐term outlook for this patient group is incompletely defined, however. Factors that require special consideration in children include the need to limit the size, depth and number of lesions, and the radiation exposure incurred during fluoroscopy‐guided catheters manipulation. The use of cryoablation seems promising in limiting lesion size. Three‐dimensional (3D) mapping systems clearly have been shown to reduce the radiation dose. In congenital heart disease, these advances in technology have helped to further our understanding of the mechanisms underlying arrhythmias. It is anticipated that earlier intervention and newer operative techniques will reduce the incidence of postoperative arrhythmias in the future. For those patients who still develop tachyarrythmias after cardiac surgery, the use of three‐dimensional systems and other new technologies permits more efficient intervention in the electrophysiology laboratory.
The ‘Epworth–China connection’
Authors: Lim Y. L. 
Published: October 2012

AbstractInterventional cardiologists from China first arrived at the Epworth Hospital in Melbourne for training in percutaneous transluminal coronary angioplasty in 1988. Percutaneous transluminal coronary angioplasty was initially performed in China in 1981 in Xian. In those days, angioplasty balloons and catheters that were brought into China mainly by foreign experts were used repeatedly until they were broken. Dr. Antonio Colombo was invited to visit Beijing, China, in 1998 to demonstrate coronary stenting at the Chaoyang Hospital. By 2010, more than 300 000 cases of percutaneous coronary interventions (PCIs) had been performed throughout China. If the current rate of PCIs per population in the West was to be applied in China, more than 4 million PCIs should have been performed annually.
ASYMMETRIC INFORMATION AND EXCHANGE OF INFORMATION ABOUT PRODUCT DIFFERENTIATION
Authors: Brandão António , Pinho Joana 
Published: October 2012

ABSTRACTWe introduce asymmetric information about consumers’ transportation costs (i.e., the degree of product differentiation) in the model of Hotelling. When transportation costs are high, both firms have lower profits with asymmetric information than with perfect information. Contrarily, if transportation costs are low, both firms may prefer the asymmetric information scenario (the informed firm always prefers the informational advantage, while the uninformed firm may or may not prefer to remain uninformed). Information exchange is ex‐ante advantageous for both firms, but ex‐post damaging if transportation costs turn out to be low. If the information is unverifiable, the informed firm does not represent a reliable source of information, since it always prefers to announce that transportation costs are high and there is no contract that induces truthful revelation.
Another Defense of Naturalized Ethics
Authors: Baeten Elizabeth 
Published: October 2012

AbstractThis essay argues against Richard Joyce, using him as an exemplar of a number of writers who purport to show that the best a naturalized ethics can provide are demands that we can hold only as moral agnostics; that is, that no moral claims can be shown to be epistemically warranted, hence no moral claims have the property of “inescapable authority” necessary for real moral discourse or deliberation. The prudent (and “dignified”) course of action is therefore to act as if moral claims had categorical standing, knowing full well that we cannot, in principle, know this. The essay proposes instead that a fully naturalized account of moral reasoning and sentiments, compatible with the commitment to understanding human beings as products of evolutionary processes, can provide “existence imperatives” necessarily implicated in our being social animals. It argues that, on the one hand, we're mistaken in believing that real moral discourse must include imperatives that hold with inescapable authority as a foundation and, on the other, that a naturalistic perspective can offer demands that are authoritative enough to make moral judgment sound.
To What Extent Can Definitions Help our Understanding? What Plato Might Have Said in His Cups
Authors: Powell John W. 
Published: October 2012

AbstractThis article argues that philosophical definitions are overrated as sources of understanding or wisdom. Socrates gives a standard argument in their favor which is often still proffered. Still, that Socrates's definitions never succeed invites an ironic reading of that argument. Plato also gives crucial arguments against treating definitions as important to understanding, and those objections have current versions. That raises an issue: What did we think definitions would do for us anyway? That question invites a reassessment of definitions that makes them less central and gives them a more humble, though still dangerous, role to play, one that requires they be integrated with surrounding examples and our own complex educations toward wisdom.