bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultralong-period Cepheids: a possible primary distance indicator?
Authors: Fiorentino G. , Annibali F. , Clementini G. , Ramos R. Contreras , Marconi M. , Musella I. , Saha A. , Tosi M. , Aloisi A. , van der Marel R.
Published: February 2013

We present a project that aims to provide a complete theoretical and observational framework for an as yet unexplored class of variable stars, the ultralong-period Cepheids (P longer than 80–100 days). Given their very high luminosities (MV up to −7 mag), with the Hubble Space Telescope we will be able to observe them easily in stellar systems located at large distances (~ 100 Mpc). This limit will be further increased, out to the Hubble flow (~ 350 Mpc), using future ground-based facilities such as the European Extremely Large Telescope. The nature of their pulsation is as yet unclear, as is their evolutionary status, which seems different from the central helium-burning phase generally associated with classical Cepheids. These objects have been found to cover a very large metallicity range, from [Fe/H] ~ −2 dex to solar values, and they are located in heterogeneous stellar systems, from dwarf to spiral galaxies. Once completely characterized, they could provide a crucial test, since they have been found in all Type Ia supernova host spiral galaxies that have been monitored for variability over long periods and that currently offer sound constraints on the estimated value of the Hubble constant.
On the scaling relations of disk galaxies
Authors: Giovanelli Riccardo
Published: February 2013

The physical background of scaling laws of disk galaxies is reviewed. The match between analytically derived and observed scaling laws is briefly discussed. Accurate modeling of the fraction of baryons that end up populating a disk, and the conversion efficiency of those into stars, remains a challenging task for numerical simulations. The measurement of rotational velocity tends to be made with criteria of convenience rather than through rigorous definition. And yet, the Tully–Fisher and the disk size versus rotational velocity relations exhibit surprisingly small scatter. Practical recipes (and costs) to optimize the quality of template relations are considered.
Cosmic distances from surface brightness fluctuations
Authors: Blakeslee John P.
Published: February 2013

High spatial-resolution measurements of surface brightness fluctuations (SBFs) with the Hubble Space Telescope (HST) provide the most precise distances available to early-type galaxies beyond the Local Group. The observable SBF magnitude in a given bandpass is a basic property of any stellar system, corresponding to a ratio of the first and second moments of the stellar luminosity function. Calibration of the method has presented challenges, but we now have an excellent empirical determination of how the SBF observable varies with galaxy color in broad bandpasses at the red end of the optical spectrum, and we are working towards a similar calibration for HST's Wide-Field Camera 3 in the near-infrared wavelength range, where the SBF magnitudes are considerably brighter. From HST Advanced Camera for Surveys data, we have determined the relative distances of the Virgo and Fornax clusters to within a precision of 2%, and resolved their internal structures. More recent measurements allow us to tie the Coma cluster, the standard of comparison for distant cluster studies, to the same precise distance scale. The SBF method can be calibrated in an absolute sense either empirically using Cepheids or theoretically based on stellar population models. The agreement between model and empirical zero points provides an independent confirmation of the Cepheid distance scale.
Visualization of structures and cosmic flows in the local Universe
Authors: Pomarède Daniel , Courtois Hélène , Tully R. Brent
Published: February 2013

A visualization of 3D structures and cosmic flows is presented using information from the Extragalactic Distance Database V8k redshift catalog and peculiar velocities from the Cosmicflows-1 survey. Structures within a volume bounded at 8000 km s−1 on the cardinal Supergalactic axes are explored in terms of both displaying the positions of the 30,124 galaxies of the catalog and its reconstructed luminosity density field, corrected to account for growing incompleteness with increasing distance. Cosmography of the local Universe is discussed with the intent to identify the most prominent structures, including voids, galaxy clusters, filaments, and walls. The mapping also benefits from precise distance measures provided through the Cosmicflows-1 observational program. Three-dimensional visualizations of the coherent flows of galaxies in the nearby Universe are presented, using recent results based on reconstruction of cosmic flows with the Wiener filter approach. The three major components of the Milky Way's motion, namely expulsion from the Local Void, infall toward the Virgo Cluster, and the bulk flow of the historic Local Supercluster toward the Great Attractor are illustrated using different visualization techniques and analyzed in light of the cosmography derived from the V8k redshift and Cosmicflows-1 distance catalogs.
Type Ia supernovae as extragalactic distance indicators
Authors: Schmidt Brian P.
Published: February 2013

Type Ia supernovae (SNe Ia) are among cosmology's most useful tools for measuring extragalactic distances. Their intrinsic brightness, MV=−19.2 mag, and precision, σ=0.12 mag, make for a unique combination to precisely probe cosmic expansion from the nearby to the high-redshift Universe. I describe the current state of the art for measuring distances to SNe Ia—focusing on the current challenges which ultimately limit their precision—as well as prospects for further refinement. I also highlight cosmological applications where they have been especially valuable, and briefly review some future projects which plan to exploit SNe Ia.
The heterogeneity of Type Ia supernova progenitor systems and their use as cosmic distance indicators
Authors: Ricker Paul , Pan Kuo-Chuan , Taam Ronald
Published: February 2013

Population synthesis modeling of Type Ia supernova (SN Ia) progenitors suggests that multiple binary evolution channels may give rise to SNe Ia. Independently of the ignition mechanism, the type of progenitor system involved affects the circumstellar environment into which the explosion propagates, as well as the amount of solid angle blocked by the companion (for single-degenerate models). Using three-dimensional adaptive-mesh simulations of SNe Ia in binary systems, we discuss the effects of the progenitor system on the observable characteristics of SNe Ia and the impact of these effects on systematic errors in the use of SNe Ia as cosmic distance indicators.
Measurement of the cosmological distance scale using X-ray and Sunyaev–Zel'dovich effect observations of galaxy clusters
Authors: Bonamente Massimiliano , Carlstrom John , Leitch Eric , Joy Marshall , Marrone Daniel , Mantz Adam , Muchovej Stephen , Plagge Thomas , Reese Erik
Published: February 2013

X-ray and Sunyaev–Zeldovich effect (SZE) observations of galaxy clusters can be used to measure their distances independently of the cosmic distance ladder. We have determined the distance to 38 clusters of galaxies in the redshift range 0.14 ≤ z ≤ 0.89 using X-ray data from the Chandra X-ray Observatory and SZE data from the Owens Valley Radio Observatory and the Berkeley–Illinois–Maryland Association interferometric arrays. We measure a Hubble constant of H0 = 76.9+3.9−3.4+10.0−8.0 km s−1 Mpc−1 (statistical followed by systematic uncertainties at 68% confidence) for an ΩM=0.3, ΩΛ=0.7 cosmology. Our determination of the Hubble parameter in the distant Universe agrees with measurements from the Hubble Space Telescope Key Project that probed the nearby Universe.
Advancing the physics of cosmic distances: Conference summary
Authors: de Grijs Richard
Published: February 2013

Knowing the distance of an astrophysical object is key to understanding it. However, at present, comparisons of theory and observations are hampered by precision (or lack thereof) in distance measurements or estimates. Putting the many recent results and new developments into the broader context of the physics driving cosmic distance determination is the next logical step, which will benefit from the combined efforts of theorists, observers and modellers working on a large variety of spatial scales, and spanning a wide range of expertise. IAU Symposium 289 addressed the physics underlying methods of distance determination across the Universe, exploring the various approaches employed to define the milestones along the road. The meeting provided an exciting snapshot of the field of distance measurement, offering not only up-to-date results and a cutting-edge account of recent progress, but also full discussion of the pitfalls encountered and the uncertainties that remain. One of the meeting's main aims was to provide a roadmap for future efforts in this field, both theoretically and observationally.
Distance estimates to five open clusters based on 2mass data of red clump giants
Authors: Chen Li , Gao Xinhua
Published: February 2013

Red clump (RC) giants are excellent standard candles in the Milky Way and the Large Magellanic Cloud. The near-infrared K-band intrinsic luminosity of RC giants exhibits only a small variance and a weak dependence on chemical composition and age. In addition, RCs are often easily recognizable in the color–magnitude diagrams of open clusters, which renders them extremely useful distance indicators for some intermediate-age or old open clusters. Here we determine the distance moduli of five Galactic open clusters covering a range of metallicities and ages, based on RC giants in the cluster regions using 2mass photometric data. We compare our result with those from main-sequence fitting and also briefly discuss the advantages and disadvantages of RC-based cluster distance determination.
Near-infrared surface brightness fluctuation measurements with the Hubble Space Telescope's WFC3/IR channel
Authors: Cho Hyejeon , Jensen Joseph B. , Blakeslee John P. , French Brigham S. , Lee Hyun-chul , Lee Young-Wook
Published: February 2013

The surface brightness fluctuation (SBF) method at near-infrared (NIR) wavelengths is a powerful tool for estimating distances to unresolved stellar systems with high precision. The IR channel of the Wide Field Camera 3 (WFC3), installed on board the Hubble Space Telescope (HST) in 2009, has a greater sensitivity and a wider field of view than the previous generation of HST IR instruments, making it much more efficient for measuring distances to early-type galaxies in the Local Volume. To take full advantage of its capabilities, we need to empirically calibrate the SBF distance method for WFC3's NIR passbands. We present the SBF measurements for the WFC3/IR F160W bandpass filter using observations of 16 early-type galaxies in the Fornax and Virgo Clusters. These have been combined with existing (g475–z850) color measurements from the Advanced Camera for Surveys Virgo and Fornax Cluster Surveys to derive a space-based H160-band SBF relation as a function of color. We have also compared the absolute SBF magnitudes to those predicted by evolutionary population synthesis models in order to study stellar population properties in the target galaxies.
Trigonometric parallaxes in the TW Hydrae Association
Authors: Ducourant C. , Teixeira R. , Chauvin G. , Krone-Martins A. , Le Campion J. F. , Galli P. , Song I. , Zuckerman B.
Published: February 2013

We have conducted a program of trigonometric distance measurements to 13 members of the TW Hydrae Association (TWA), which will enable us (through back-tracking methods) to derive a convincing estimate of the age of the association, independent of stellar evolutionary models. With age, distance, and luminosity known for an ensemble of TWA stars and brown dwarfs, models of early stellar evolution (which are still uncertain for young ages and substellar masses) will then be constrained by observations over a wide range of masses (0.025 to 0.7 M⊙).
Kinematic distances of pre-main-sequence stars in the Lupus star-forming region
Authors: Galli P. A. B. , Teixeira R. , Ducourant C. , Bertout C.
Published: February 2013

To reliably determine the main physical parameters (masses and ages) of young stars, we must know their distances. While the average distance to nearby star-forming regions (<300 pc) is often known, the distances to individual stars are usually unknown. Individual distances to members of young moving groups can be derived from their radial velocities and proper motions using the convergent-point strategy. We investigate the kinematic properties of the Lupus moving group with the primary objective of deriving individual distances to all group members.
Global survey of star clusters in the Milky Way: The open cluster distance scale
Authors: Kharchenko N. V. , Piskunov A. E. , Röser S. , Schilbach E. , Scholz R.-D.
Published: February 2013

We present the Milky Way Star Clusters (MWSC) survey based on 470 million stars extracted from the all-sky catalogues PPMXL and 2mass. The target list comprises 3784 entries and includes all open and globular clusters, as well as all cluster candidates, known at present. By means of a combined photometric/astrometric pipeline process, we determine individual membership probabilities for cluster stars and provide fundamental cluster parameters such as cluster centre coordinates, mean proper motions, radial velocity, distance, reddening, age and tidal radius. This sample includes ~ 700 clusters with fundamental parameters based on optical data and offers a good opportunity for a comparison of the near-infrared (NIR) and optical cluster distance scales. We find that distances and reddening values obtained from the colour–magnitude diagrams (CMDs) in the NIR agree well with earlier distance estimates based on optical CMDs. These newly obtained homogeneous distances, together with the other cluster parameters, allow us to study the properties of the open cluster population in the Galactic disk.
VERA observations of the Galactic star-forming regions ON1 and ON2N
Authors: Nagayama Takumi ,   VERA project members
Published: February 2013

We carried out astrometric observations with VERA of H2O masers in ON1 and ON2N. The measured distances to ON1 and ON2N are 2.47 ± 0.11 and 3.83 ± 0.13 kpc, respectively. We found that ON1 and ON2N are located near the tangent point and the Solar circle, respectively. We derive an angular velocity of the Galactic rotation at the Sun's position (i.e. the ratio of the Galactic constants) of 28 ± 2 km s−1 kpc−1 using the measured distances and three-dimensional velocity components of the two sources. This value is consistent with recent estimates obtained using Very Long Baseline Interferometry but different from the IAU-recommended value of 25.9 km s−1 kpc−1.
Galactocentric distance of the Sun derived from kinematic data
Authors: Zhu Zi , Shen Ming
Published: February 2013

Based on radial velocity data and Hipparcos proper motions, we present a new determination of the Galactocentric distance based on a purely kinematic model. We have selected three subgroups of Galactic thin-disk components (O–B5 stars, classical Cepheids and Galactic open clusters) to trace the local structure and kinematics of the Galactic disk. Adopting the approximation of axisymmetric circular rotation, we have derived the Sun's distance to the Galactic Center, R0 = 8.25 ± 0.79 kpc based on O–B5 stars, R0 = 7.98 ± 0.79 kpc based on Galactic Cepheids and R0 = 8.03 ± 0.70 kpc using open clusters, all of which are in excellent agreement with the current-best estimate of the Galactocentric distance.
Model order selection for digital predistortion of a RF power amplifier when the distortion spectrum exceeds the observation bandwidth
Authors: Braithwaite R. Neil
Published: February 2013

Digital predistortion (DPD) of a nonlinear power amplifier (PA) is made challenging when the observation bandwidth (OBW) used to measure the output signal is narrower than the intermodulation distortion (IMD) spectrum generated. Wide bandwidth input signals stimulate memory effects within the PA thereby requiring the model order of the DPD to be expanded to include memory correction coefficients. However, if the model order is over-specified relative to the OBW, the estimation of the DPD coefficients will be ill-conditioned and the distortion cancellation will be degraded. This paper proposes a method of selecting the best model order of the DPD coefficient estimation for the available OBW. Adjacent channel power ratio (ACPR) is used as an independent measure of the distortion cancellation for a given model order. Experimental results demonstrate the relationship between the model order of the estimation, the OBW, and the ACPR performance of the wide bandwidth IMD cancellation.
Alkohol in Opioidsubstitution – zwischen therapeutischem Risiko, Patientenwohl und Public Health
Authors: Falcato Luis Manuel , Dampz Magdalena , Bruggmann Philip
Published: February 2013

Fragestellung: Ausprägung des Alkoholkonsums und des Zusammenhangs der Intensität des Alkoholkonsums mit der Einsicht in die Notwendigkeit einer Trinkmengenreduktion bzw. der Therapiebereitschaft unter opioid-substituierten Patienten. Methodik: Standardisierte, mündliche Erhebung von Selbstangaben in einer naturalistischen Behandlungs-Kohorte in opioid gestützter Behandlung (n = 140) in einem Setting mit minimalen Behandlungsrestriktionen hinsichtlich weiterer Substanzstörungen. Ergebnisse: Der Anteil mit unproblematischem Konsum lag bei 62 %. 23 % zeigten einen riskanten (AUDIT 8 – 15), 15 % einen schädlichen oder abhängigen Alkoholkonsum (AUDIT ≥16). Die AUDIT-Risiko-Levels waren positiv mit Konsum von Opioiden und Benzodiazepinen und negativ mit sozialer Integration assoziiert. Alle Patienten mit AUDIT-Score ≥16 und 47 % der riskant Trinkenden zeigten Problembewusstsein. 62 % der Patienten mit AUDIT ≥16 äußerten Therapiebereitschaft. Kontrollverlust bei Männern und Schuldgefühle bei Frauen waren die häufigsten Konsequenzen des Trinkens. Schlussfolgerungen: Übermässiger Alkoholkonsum ist ein vordringliches Problem in der Substitutionstherapie. Routinemäßiges Alkohol-Screening bei Beginn und während der Behandlung ist empfehlenswert. Problematischer Alkoholkonsum sollte im Sinne einer Komplikation unter umfassender, individueller Nutzen-Risiken-Abwägung in die Behandlung einbezogen werden. Der Integration geeigneter therapeutischer Angebote sollte hohe Priorität eingeräumt werden.
Der Zusammenhang zwischen Sucht und Schlaf: „legale“ Drogen
Authors: Jähne Andreas , Unbehaun Thomas , Riemann Dieter
Published: February 2013

Fragestellung: Ziel ist die Darstellung der Schlafbeeinflussung durch die weit verbreiteten „Alltagsdrogen“ Koffein, Alkohol und Nikotin. Ergebnisse: Während Koffein und Nikotin als stimulierende Substanzen schlafinhibierende Effekte haben, überwiegen beim Alkohol die schlafinduzierenden Wirkungen. Im Nikotin- und Alkoholentzug sind insomnische Beschwerden häufige Symptome, die Einfluss auf die Abstinenzerwartung nehmen können. Dabei scheinen sich Substanzkonsum, insomnische und depressive Symptome wechselseitig zu beeinflussen. Aber auch periodische Beinbewegungen oder schlafassoziierte Atmungsstörungen können die Schlafqualität reduzieren. Beeinträchtigte Schlafqualität wiederum geht mit einem erhöhten Risiko für Depression und Substanzkonsum einher. Schlussfolgerung: Schlafstörungen bei Alkohol- und Tabakabhängigkeit sollten deshalb frühzeitig erkannt und behandelt werden. Das Fehlen prospektiver Interventionsstudien erschwert die Beurteilung des Einflusses einer Therapie der Schlafstörungen auf Abstinenz und psychiatrische Komorbidität.
„Badesalz“-Psychosen – Klinische Aspekte
Authors: Livak Vitali , Ehemann Michael , Pilz-Gerhardinger Magdalena , Werner Petra , Epoupa Leonhard , Tretter Felix
Published: February 2013

Einführung: Seit Ende 2011 ist die Zahl der Aufnahmen von Patienten mit psychotischer Symptomatik nach Konsum von synthetischen Cathinonen in unserer Suchtabteilung auf 2 – 3 Fälle pro Woche angestiegen (ca. 3 % aller Aufnahmen). Fallberichte: Wir berichten über sieben dieser Fälle, die in den letzten acht Monaten behandelt wurden. Die Patienten zeigten psychotische Symptomatik mit Wahn, Denkstörungen und optischen, sowie akustischen Halluzinationen. Einige waren agitiert, desorientiert, hilflos oder litten an oralen Dyskinesien. Die Therapien waren supportiv und beinhalteten typische und atypische Neuroleptika, Benzodiazepine und Clonidin. Die psychotische Symptomatik remittierte in fünf der sieben Fälle, zwei Patienten wurden nach einigen Behandlungstagen mit noch anklingender psychotischer Symptomatik entlassen. Diskussion: Das Psychosepotential der Cathinone sollte als hoch betrachtet werden. Die Droge wirkt entaktogen und hat ein hohes Suchtpotential. Aufgrund der weiten Verbreitung im Internet und der steigenden Popularität auch für Patienten ohne Erfahrungen mit illegalen Drogen, ebenso wie die unzureichende Labordiagnostik stellen synthetische Cathinone ein erhebliches diagnostisches und therapeutisches Problem für spezialisierte Suchtstationen, ebenso wie ambulante Einrichtungen dar. Schlussfolgerungen: Die wachsende Fallzahl und die alarmierenden Auswirkungen, verursacht durch den Konsum dieser Substanzen, zeigen, dass weitere Forschungsarbeit notwendig ist, um diese neue Droge und ihre Wirkungen auf den menschlichen Körper besser zu verstehen und um synthetische Cathinone in Routine-Drogentests untersuchen und neue Behandlungsleitlinien entwickeln zu können.
Challenges in Norm Formation and Adherence
Authors: Krumm Stefan , Terwiel Katrin , Hertel Guido
Published: February 2013

Due to the growing globalization of business processes, teamwork increasingly requires intercultural skills. Furthermore, many teams rely predominantly on electronic collaboration (virtual teams), requiring team members to develop and adhere to norms in a cue-deprived environment. In the current study, we conducted an online survey with 171 participants who fell into one of two subgroups of cross-cultural teams: members of either traditional or virtual teams. We compared the two groups of team members with regard to their importance ratings of several competencies for team performance. Starting with a large set of intercultural competencies derived from the literature, exploratory factor analyses yielded a four-dimensional solution (working conscientiously, coping with stress and ambiguity, openness and perspective taking, and knowledge about other cultures). Among those clusters, only the cluster working conscientiously yielded substantial differences between traditional and virtual-team members, indicating specific requirements for cross-cultural collaboration for virtual as compared to traditional teams.
Healable Polymeric Materials
Authors: Greenland Barnaby W. , Hayes Wayne
Published: February 2013

This chapter affords a concise introduction to the rapidly developing field of healable polymeric materials and has been written with the synthetic polymer chemist in mind, with the specific aim of bridging the technical ‘language’ barriers between chemistry and materials science.

Definitions of the different categories of healable materials are outlined before an overview is provided. This overview is aimed at the practicing chemist and concerns the techniques currently employed to study the healablity of these fascinating new materials. The key techniques required to study healable polymeric materials—including impact testing and rheometry—are described.
Healable Supramolecular Polymeric Materials
Authors: Greenland Barnaby W. , Fiore Gina L. , Rowan Stuart J. , Weder Christoph
Published: February 2013

This chapter details the design, synthesis and evaluation techniques required to produce healable supramolecular materials. Key developments in supramolecular polymer chemistry that laid down the design concepts necessary to produce responsive materials are summarized. Subsequently, select examples from the literature concerning the synthesis and analysis of healable materials containing hydrogen bonding, π−π stacking and metal–ligand interactions are evaluated. The last section describes the most recent efforts to produce healable gels for niche applications, including electrolytes and tissue engineering scaffolds. The chapter also describes the design criteria and production of nano-composite materials that exhibit dramatically increased strength compared to previous generations of supramolecular materials, whilst still retaining the key healing characteristics.
Study of Flavor Volatile Profile in Microencapsulated Greek Saffron Products
Authors: Chranioti Charikleia , Papoutsakis Stephanos , Nikoloudaki Aspasia , Tzia Constantina
Published: February 2013

This study looks at the volatile flavor profile for the herb saffron. In recent years, ultrasound-assisted extraction (USE) has been used for the isolation of bioactive principles from plant materials using organic solvents. The main advantages of the USE method are high extraction efficiency, lower equipment cost, ease of operation, little or no sample preparation, and lower extraction temperatures. In addition, a determination of the best agent to use for microencapsulation of the saffron sample is discussed.
Effect of Addition of Cryoprotectants on Frozen/Thawed Mashed Potatoes Flavor by Sensory Evaluation
Authors: Bikaki Nantia , Virginia Giannou , Tzia Constantina
Published: February 2013

Frozen purees made from vegetables are a relatively new kind of high-quality and functional product, offering extended shelf life, better manufacturing, distribution flexibility and food safety. Mashed potatoes may be suitable for freezing as a ready-meal component or as a single product. However, freezing and thawing adversely affect the cells and cell components of mashed vegetables causing textural changes and more importantly degradation of sensory properties. The quality of mashed potatoes is influenced by various factors but more importantly by the sensory characteristics which are significant for consumer selection and acceptability. Recent studies have demonstrated that incorporation of cryoprotectant blends, such as non-starchy hydrocolloids, to starch based products like mashed potatoes is effective for ameliorating the detrimental effects of freezing and thawing. Hydrocolloids offer a protection to cells and cell components against the deleterious effects of thawing in particular, such as starch retrogradation, syneresis etc, since they interact with water and have been reported to slow down the rate of ice crystal growth and alter crystal shapes. Moreover, studies have proved the dependency between the structure of starch and the flavor of thawed potato products, affecting also the taste, texture, color and odor of these products. Recently, is attempted to incorporate prebiotic agents and dietary fiber as they enhance flavor and products become more appealing to consumers pursuing a healthy diet. The purpose of this research was to investigate the effect of addition of cryoprotectants on frozen/thawed mashed potatoes flavor and texture properties examined by sensory evaluation. The frozen/thawed samples were stored for two months and the change of flavor and texture during storage was monitored. The cryoprotectant materials that were investigated, were polysaccharides (κ-carrageenan, xanthan gum, chitosan), oligosaccharides (inulin), disaccharides (trehalose), dietary fiber (oat, potato fiber) and hydrocolloids (HPMC) and were incorporated in samples individually or as blends. The samples of frozen/thawed mashed potatoes were subjected to a quantitative descriptive profile analysis. Sensory evaluation was conducted by an eight-member panel with specific training on completing the tests. The assessors scored separately 5 sensory characteristics of texture, such as gummy, cohesive, flavor and odor using a 10-point scale. Also, a pleasure scoring for the Overall Acceptance (OA) of the samples was carried out based on all sensory attributes using also a 10-point scale. Finally, statistical analysis of sensory data was carried out for further processing of results and conclusions.
Antimicrobial Activity of Natural Flavor Components Incorporated into Edible Films in Meat Products
Authors: Chanioti Sofia , Katsigiannis Andreas , Tzia Constantina
Published: February 2013

Spices and herbs have been added to foods since ancient times, not only as flavoring agents, but also as medicine and food preservatives. The interest to replace synthetic preservatives, which have been used in foods for decades and may lead to deleterious health consequences, with natural, effective and nontoxic compounds, has increased. Many studies have demonstrated that natural flavor antimicrobial components, such as plant extracts, when incorporated into the edible films, can be effective in reducing the levels of foodborne organisms. The aim of this study was to examine the antimicrobial effectiveness of natural flavor components incorporated in the edible films or directly into the mass of the product, on the microbiological profile and the changes in quality characteristics, such as structure and color, in meat products.
Application of Non-targeted Approach in Flavor Science: A Review
Authors: Mi Lee Sang , Kim Young-Suk
Published: February 2013

Metabolomic approaches have been able to provide valuable information in many scientific areas. The importance of metabolomics in the quality, processing and safety of raw materials and final products in food science has recently increased. In particular, non-targeted approach attempt to gather information on as many components as possible in food systems by taking into account all information present in the data sets prior to the components actually being identified. While targeted analysis focuses on a limited set of components of primary interest, a non-targeted metabolomic approach enables a more holistic and unbiased analysis of samples. This review focuses on the recent trends and potential applications of non-targeted approach in flavor science and technology.
Oil and Phytochemicals from Small Fruit Seeds
Authors: Shahidi Fereidoon , Perera Nishani
Published: February 2013

By-products from agricultural resources may be used for the production of a myriad of value-added products. In the production of juice from small fruits, primarily berries, the left-over seeds may be used to produce an oil (11–23%) and a seed meal (flour). The oils so produced contain a high proportion of polyunsaturated fatty acids and a high antioxidant content with good oxidative stability and anti-inflammatory activity. These oils are rich in α-linolenic acid with a favourable n-6/n-3 fatty acid ratio compared with most vegetable oils. A wide variety of phytochemicals, such as phenolic acids, anthocyanin, flavonol and carortenoids are also present in both the oil and the seed flour. All berry seed oils contain a high amount of p-coumaric acid followed by tyrosol, vanillic acid, ferulic acid, sinapic acid and vanillin. The tocol content varies widely in both the oil and seed flour and contributes to the good storage stability of products which are of special interest for health promotion and disease risk reduction. Their potential use in a variety of applications in foods as well as cosmetics and pharmaceutical products is envisaged.
Comparison of Anti-proliferative and Anti-inflammatory Effects of Nobiletin and Its Urinary Metabolite, 3′,4′-Didemethylnobiletin
Authors: Lai Ching-Shu , Chang Grace S. , Li Shiming , Lo Chih-Yu , Ho Chi-Tang , Pan Min-Hsiung
Published: February 2013

Nobiletin is a polymethoxyflavone (PMF) present in citrus fruits, particularly in the peel. Our previous studies have identified that 3′,4′-didemethylnobiletin (DDMN) is one of the major metabolites of nobiletin in mouse urine and it has been shown to exhibit anti-inflammatory and anti-tumor promoting activity. In this study, we investigated the anti-proliferative and anti-inflammatory properties of these two compounds. The results demonstrated that both nobiletin and DDMN were able to induce cytotoxicity, cell cycle arrest and apoptosis in COLO205 cancer cells. Nobiletin showed a better activity on inducing apoptosis than its metabolite DDMN. In addition, treatment with nobiletin resulted in G1 phase cell cycle arrest, whereas DDMN caused G2/M phase arrest in COLO205 cancer cells. In anti-inflammatory analysis, DDMN showed a greater activity on inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production and protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in murine RAW264.7 macrophage. These results suggest that the anti-proliferative and anti-inflammatory activities of nobiletin and DDMN may undergo different mechanism.
Suppression of the Deformation of Raji Cells by (E)-2-Alkenals, Aroma Components of Coriander (Coriandrum Sativum L.) Leaves, and Behavior of (E)-2-Dodecenal in Rat Blood
Authors: Kano S. , Maeyama K. , Wang Y. , Kondo A. , Furumoto T. , Fukui H. , Tamura H.
Published: February 2013

(E)-2-alkenals (C10-C16), isolated from coriander (Coriandrum sativum L.) leaves, were found to be a chemopreventive agent for deformation of Raji cells carrying the genome of Epstein-Barr virus (EBV) early antigen, induced by 12-O-teradecanoylphorbol 13-acetate (TPA). Intensities of chemopreventive activity of (E)-2-alkenals (C6-C14) were positively correlated with the carbon chain length of the unsaturated aldehydes. The α,β-unsaturated double bond was found to be the most essential molecular requirement for the activity in its chemical structure and activity relationship. Furthermore, it was established that the behavior of administered (E)-2-dodecenal in rat blood was successfully monitored by the dynamic amount of (E)-2-dodecenal through a plastic cannular. In consequence, administered (E)-2-dodecenal in blood disappeared at 30 min after the administration. Additionally, ca 1% of administered (E)-2-dodecenal was observed in the environmental air emitted from rat breath or rat skin at 90 min after the administration by Tenax TA adsorbent. The chemopreventive agent, (E)-2-dodecenal mostly stayed in the rat body. These kinds of monitoring systems are helpful in understanding the metabolism of useful food components for nutraceutical science.
G16R single nucleotide polymorphism but not haplotypes of the β2-adrenergic receptor gene alters cardiac output in humans
Authors: Rokamp Kim Z. , Staalsoe Jonatan M. , Gartmann Martin , Sletgaard Anna , Nordsborg Nicolai B. , Secher Niels H. , Nielsen Henning B. , Olsen Niels V.
Published: February 2013

Variation in genes encoding the β2-adrenergic receptor (ADRB2) and angiotensin-converting enzyme (ACE) may influence Q̇ (cardiac output). The 46G>A (G16R) SNP (single nucleotide polymorphism) has been associated with β2-mediated vasodilation, but the effect of ADRB2 haplotypes on Q̇ has not been studied. Five SNPs within ADRB2 (46G>A, 79C>G, 491C>T, 523C>A and 1053G>C by a pairwise tagging principle) and the I/D (insertion/deletion) polymorphism in ACE were genotyped in 143 subjects. Cardiovascular variables were evaluated by the Model flow method at rest and during incremental cycling exercise. Only the G16R polymorphism was associated with Q̇. In carriers of the Arg16 allele, Q̇rest (resting Q̇) was 0.4 [95% CI (confidence interval), 0.0–0.7] l/min lower than in G16G homozygotes (P=0.048). During exercise, the increase in Q̇ was by 4.7 (95% CI, 4.3–5.2) l/min per litre increase in pulmonary V̇O2 (oxygen uptake) in G16G subjects, but the increase was 0.5 (0.0–0.9) l/min lower in Arg16 carriers (P=0.035). A similar effect size was observed for the Arg16 haplotypes ACCCG and ACCCC. No interaction was found between ADRB2 and ACE polymorphisms. During exercise, the increase in Q̇ was 0.5 (CI, 0.0 –1.0) l/min greater in ACE I/I carriers compared with I/D and D/D subjects (P=0.054). In conclusion, the ADRB2 Arg16 allele in humans is associated with a lower Q̇ both at rest and during exercise, overriding the effects of haplotypes.
Wavelet statistical texture features‐based segmentation and classification of brain computed tomography images
Authors: Padma Nanthagopal A. , Sukanesh R.
Published: February 2013

A computer software system is designed for segmentation and classification of benign and malignant tumour slices in brain computed tomography images. In this study, the authors present a method to select both dominant run length and co‐occurrence texture features of wavelet approximation tumour region of each slice to be segmented by a support vector machine (SVM). Two‐dimensional discrete wavelet decomposition is performed on the tumour image to remove the noise. The images considered for this study belong to 208 tumour slices. Seventeen features are extracted and six features are selected using Student's t‐test. This study constructed the SVM and probabilistic neural network (PNN) classifiers with the selected features. The classification accuracy of both classifiers are evaluated using the k fold cross validation method. The segmentation results are also compared with the experienced radiologist ground truth. Quantitative analysis between ground truth and the segmented tumour is presented in terms of segmentation accuracy and segmentation error. The proposed system provides some newly found texture features have an important contribution in classifying tumour slices efficiently and accurately. The experimental results show that the proposed SVM classifier is able to achieve high segmentation and classification accuracy effectiveness as measured by sensitivity and specificity.
Framework for image retrieval using machine learning and statistical similarity matching techniques
Authors: Fakheri Majid , Sedghi Tohid , Shayesteh Mahrokh G. , Amirani Mehdi Chehel
Published: February 2013

The aim of this study is to take advantage of both shape and texture properties of image to improve the performance of image indexing and retrieval algorithm. Further, a framework for partitioning image into non‐overlapping tiles of different sizes, which results in higher retrieval efficiency, is presented. In the new approach, the image is divided into different regions (tiles). Then, the energy and standard deviation of Hartley transform coefficients of each tile, which serve as the local descriptors of texture, are extracted as sub‐features. Next, invariant moments of edge image are used to record the shape features. The shape features and combination of sub‐features of texture provide a robust feature set for image retrieval. The most similar highest priority (MSHP) principle is used for matching of textural features and Canberra distance is utilised for shape features matching. The retrieved image is the image which has less MSHP and Canberra distance from the query image. The proposed method is evaluated on three different image sets, which contain about 17 000 images. The experimental results indicate that the proposed method achieves higher retrieval accuracy than several previously presented schemes, whereas the computational complexity and processing time of the new method are less than those of other approaches.
Launching and Steering a Green IT Company: The Case of GreenField Software
Authors: Abraham Thomas
Published: February 2013

This teaching case discusses the challenges facing GreenField Software (GFS), a start-up company offering software products and services to support sustainability. The case describes the start-up process, the crafting of the firm's strategy and structure, and the development of its products and services in the emerging ‘green Information Technology (IT)’ industry. It follows the key decisions made by the CEO and his executive team as they navigate a shifting and increasingly competitive marketplace. As GFS approaches the 2-year anniversary of its launch, the team must decide several key issues. These include whether to market their product as a business continuity solution or as a ‘green IT’ solution; what intellectual property will differentiate them from the competition; and how to respond to the changing needs of the marketplace.
Infinite swapping replica exchange molecular dynamics leads to a simple simulation patch using mixture potentials
Authors: Lu Jianfeng , Vanden-Eijnden Eric
Published: February 2013

Replica exchange molecular dynamics (REMD) becomes more efficient as the frequency of swap between the temperatures is increased. Recently Plattner et al. [J. Chem. Phys. 135, 134111 (2011)10.1063/1.3643325] proposed a method to implement infinite swapping REMD in practice. Here we introduce a natural modification of this method that involves molecular dynamics simulations over a mixture potential. This modification is both simple to implement in practice and provides a better, energy based understanding of how to choose the temperatures in REMD to optimize efficiency. It also has implications for generalizations of REMD in which the swaps involve other parameters than the temperature.
Effects of time delay on the stochastic resonance in small-world neuronal networks
Authors: Yu Haitao , Wang Jiang , Du Jiwei , Deng Bin , Wei Xile , Liu Chen
Published: February 2013

The effects of time delay on stochastic resonance in small-world neuronal networks are investigated. Without delay, an intermediate intensity of additive noise is able to optimize the temporal response of the neural system to the subthreshold periodic signal imposed on all neurons constituting the network. The time delay in the coupling process can either enhance or destroy stochastic resonance of neuronal activity in the small-world network. In particular, appropriately tuned delays can induce multiple stochastic resonances, which appear intermittently at integer multiples of the oscillation period of weak external forcing. It is found that the delay-induced multiple stochastic resonances are most efficient when the forcing frequency is close to the global-resonance frequency of each individual neuron. Furthermore, the impact of time delay on stochastic resonance is largely independent of the small-world topology, except for resonance peaks. Considering that information transmission delays are inevitable in intra- and inter-neuronal communication, the presented results could have important implications for the weak signal detection and information propagation in neural systems.
Effect of dielectric permittivity variation in the transmission spectra of non-compact 2D-arrays of dielectric spheres
Authors: Morales P. , Andueza A. , Sevilla J.
Published: February 2013

Transmission spectra of two dimensional photonic crystals made of arrays of dielectric spheres are affected by the sphere dielectric permittivity. In this paper we present a systematic study of this influence for different compactness of the lattices. The transmission spectra were simulated by finite-different time-domain method. The system studied is a plane of spheres of dielectric permittivity ε (ranging from 2 to 9) arranged in triangular symmetry with varying compactness. Compactness is characterized as the ratio (R) of the sphere diameter (Φ) over the lattice period (Λ) and is considered from R = 1, close packed samples, to R = 0, 2. The transmission spectra of these samples are calculated for normal incident radiation of wavelengths in the interval extending from 0.8 to 5 times the sphere diameter. The sphere arrays present a number of resonant modes that appear as dips in the transmission spectra. The frequency position of the resonances is discussed in relation to those of the Mie modes of the isolated spheres and the frequency of the Bragg diffraction. For high values of ε and high compactness, the resonances of the single layer are dominated by the Mie modes, while for low ε and low compactness, the resonances tend to the Bragg diffraction values. It is possible to establish a quantitative threshold between these two regimes in terms of the effective permittivity.
Effects of annealing temperature on the characteristics of Ga-doped ZnO film metal-semiconductor-metal ultraviolet photodetectors
Authors: Yang L. C. , Wang R. X. , Xu S. J. , Xing Z. , Fan Y. M. , Shi X. S. , Fu K. , Zhang B. S.
Published: February 2013

Metal-semiconductor-metal ultraviolet photodetectors were fabricated by using the sputtered Ga-doped ZnO (GZO) thin films on sapphire substrate as an active layer. Current-voltage (I-V) and opto-electrical characteristics of the devices were investigated. It is found that the peak optical responsivity of the devices can be significantly improved by selecting appropriate thermal annealing temperature, i.e., from 12.0 A/W (annealed at 500 °C) and 54.0 A/W (700 °C). Furthermore, dark current of the devices drops by two orders of magnitude after annealing process. The significant improvement in performance of the device is ascribed to the removal of massive defect centers of the GZO thin films and increase of Schottky barrier height between the GZO and metal electrodes after thermal annealing at appropriate temperatures.
Femtosecond ultraviolet laser ablation of silver and comparison with nanosecond ablation
Authors: Toftmann B. , Doggett B. , Budtz-Jørgensen C. , Schou J. , Lunney J. G.
Published: February 2013

The ablation plume dynamics arising from ablation of silver with a 500 fs, 248 nm laser at ∼2 J cm−2 has been studied using angle-resolved Langmuir ion probe and thin film deposition techniques. For the same laser fluence, the time-of-flight ion signals from femtosecond and nanosecond laser ablation are similar; both show a singly peaked time-of-flight distribution. The angular distribution of ion emission and the deposition are well described by the adiabatic and isentropic model of plume expansion, though distributions for femtosecond ablation are significantly narrower. In this laser fluence regime, the energy efficiency of mass ablation is higher for femtosecond pulses than for nanosecond pulses, but the ion production efficiency is lower.
Probing high-Reynolds-number effects in numerical boundary layers
Authors: Pirozzoli Sergio , Bernardini Matteo
Published: February 2013

We study the high-Reynolds-number behavior of a turbulent boundary layer in the low supersonic regime through very-large-scale direct numerical simulation (DNS). For the first time a Reynolds number is attained in DNS (\documentclass[12pt]{minimal}\begin{document}$\mbox{\textit {Re}}_{\tau } = \delta /\delta _v \approx 4000$\end{document}Reτ=δ/δv≈4000, where δ is the boundary layer thickness and δv is the viscous length scale) at which theoretical predictions and experiments suggest the occurrence of phenomena pertaining to the asymptotic Reynolds number regime. From comparison with previous DNS data at lower Reynolds number we find evidence of a continuing trend toward a stronger imprint of the outer-layer structures onto the near-wall region. This effect is clearly manifested both in flow visualizations, and in energy spectra. More than a decade of nearly-logarithmic variation is observed in the mean velocity profiles, with log-law constants k ≈ 0.394, C ≈ 4.84, and a trend similar to experiments. We find some supporting evidence for the debated existence of a k−1 region in the power spectrum of streamwise velocity fluctuations, which extends up to y+ ≈ 150, and of a k−5/3 spectral range in the outer layer.