bluuebunny/crossref_metadata_2025_split huggingface dataset:
The XMM–Newton long look of NGC 1365: uncovering of the obscured X-ray source
Authors: Risaliti G. , Salvati M. , Elvis M. , Fabbiano G. , Baldi A. , Bianchi S. , Braito V. , Guainazzi M. , Matt G. , Miniutti G. , Reeves J. , Soria R. , Zezas A. 
Published: December 2008

Abstract
We present an analysis of the extreme obscuration variability observed during an XMM–Newton 5-d continuous monitoring of the active galactic nuclei (AGN) in NGC 1365. The source was in a reflection-dominated state in the first ∼1.5 d, then a strong increase in the 7—10 keV emission was observed in ∼10 h, followed by a symmetric decrease. The spectral analysis of the different states clearly shows that this variation is due to an uncovering of the X-ray source. From this observation, we estimate a size of the X-ray source DS &lt; 1013 cm, a distance of the obscuring clouds R∼ 1016 cm and a density n∼ 1011 cm−3. These values suggest that the X-ray absorption/reflection originates from the broad-line region clouds. This is also supported by the resolved width of the iron narrow Kα emission line, consistent with the width of the broad Hβ line.
Transit infrared spectroscopy of the hot Neptune around GJ 436 with the Hubble Space Telescope
Authors: Pont F. , Gilliland R. L. , Knutson H. , Holman M. , Charbonneau D. 
Published: December 2008

Abstract
The nearby transiting system GJ 436b offers a unique opportunity to probe the structure and atmosphere of an extrasolar ‘hot Neptune’. In this Letter, we present the main results of observations covering two transit events with the Near Infrared Camera and Multi Object Spectrograph (NICMOS) camera on the Hubble Space Telescope (HST). The data consist in high-cadence time series of grism spectra covering the 1.1–1.9 µm spectral range. We find Rpl= 4.04 ± 0.10 R⊕ and R*= 0.446 ± 0.011 R⊙ for the planet and star radius, confirming and improving earlier measurements with a ground-based photometry and a Spitzer light curve at 8 µm, as opposed to a much higher value obtained with the Fine Guidance Sensor on the HST. We measure no departure from strict periodicity in the transits to the level of ∼7 s. This strongly disfavours the proposed explanation of the orbital eccentricity of GJ 436b in terms of the perturbation by another close-by planet. We measure a flat transmission spectrum at the level of a few parts per 10 000 in flux, with no significant signal in the 1.4-µm water band to a level comparable to the maximum amplitude of the effect predicted by planetary atmosphere models.
Discovery of a 30-d period in the supergiant fast X-ray transient SAX J1818.6–1703
Authors: Bird A. J. , Bazzano A. , Hill A. B. , McBride V. A. , Sguera V. , Shaw S. E. , Watkins H. J. 
Published: December 2008

Abstract
SAX J1818.6–1703 has been characterized as a supergiant fast X-ray transient system on the basis of several INTEGRAL/IBIS detections since the original BeppoSAX Wide Field Camera detection. Using IBIS/ISGRI, Swift/BAT and archival observations, we show that, in fact, SAX J1818.6–1703 exhibits emission on a period of 30 ± 0.1 d, with a high degree of recurrence. SAX J1818.6–1703 is therefore the second supergiant fast X-ray transient shown to exhibit periodic outbursts, but with a considerably shorter period than the other known system, IGR J11215–5952.
TeV variability in blazars: how fast can it be?
Authors: Ghisellini G. , Tavecchio F. , Bodo G. , Celotti A. 
Published: December 2008

Abstract
Recent Cerenkov observations of the two BL Lac objects PKS 2155–304 and Mkn 501 revealed TeV flux variability by a factor of ∼2 in just 3–5 min. Even accounting for the effects of relativistic beaming, such short time-scales are challenging simple and conventional emitting models, and call for alternative ideas. We explore the possibility that extremely fast variable emission might be produced by the particles streaming at ultra-relativistic speeds along magnetic field lines and inverse-Compton scattering any radiation field already present. This would produce extremely collimated beams of TeV photons. While the probability for the line of sight to be within such a narrow cone of emission would be negligibly small, one would expect that the process is not confined to a single site, but can take place in many very localized regions, along almost straight magnetic lines. A possible astrophysical setting realizing these conditions is magneto-centrifugal acceleration of beams of particles. In this scenario, the variability time-scale would not be related to the physical dimension of the emitting volume, but might be determined by either the typical duration of the process responsible for the production of these high-energy particle beams or by the coherence length of the magnetic field. It is predicted that even faster TeV variability — with no X-ray counterpart — should be observed by the foreseen more sensitive Cerenkov telescopes.
Magnetohydrodynamic turbulence in supernova remnants
Authors: Roy Nirupam , Bharadwaj Somnath , Dutta Prasun , Chengalur Jayaram N. 
Published: December 2008

Abstract
We present estimates of the angular power spectra of the synchrotron radiation intensity fluctuations at 6 and 20 cm for the shell-type supernova remnant Cas A and the filled-centre Crab supernova remnant. We find that the intensity fluctuations of both the sources have a power-law power spectrum with index −3.24 ± 0.03. This power-law power spectrum is consistent with the magnetohydrodynamic turbulence in the synchrotron emitting plasma. For Cas A, there is a break in the power spectrum and the power-law index changes from −3.2 to −2.2 at large angular scale. This transition occurs at an angular scale that corresponds to the shell thickness of Cas A. We interpret this as a transition from three- to two-dimensional turbulence on scales that are, respectively, smaller and larger than the shell thickness.
Cores and cusps in the dwarf spheroidals
Authors: Evans N. W. , An J. , Walker M. G. 
Published: December 2008

Abstract
We consider the problem of determining the structure of the dark halo of nearby dwarf spheroidal galaxies (dSphs) from the spherical Jeans equations. Whether the dark haloes are cusped or cored at the centre is an important strategic problem in modern astronomy. The observational data comprise the line-of-sight velocity dispersion of a luminous tracer population. We show that when such data are analysed to find the dark matter density with the spherical Poisson and Jeans equations, then the generic solution is a dark halo density that is cusped like an isothermal (ρD∝r−2). Although milder cusps (like the Navarro–Frenk–White ρD∝r−1) and even cores are possible, they are not generic. Such solutions exist only if the anisotropy parameter β and the logarithmic slope of the stellar density γℓ satisfy the constraint γℓ= 2β at the centre or if the radial velocity dispersion falls to zero at the centre. So, for example, a dSph with an exponential light profile can exist in Navarro–Frenk–White halo and have a flat velocity dispersion, but anisotropy in general drives the dark halo solution to an isothermal cusp. The identified cusp or core is therefore a consequence of the assumptions (particularly of spherical symmetry and isotropy), and not the data.
Impact of subsolar metallicities on photometric redshifts
Authors: Kotulla Ralf , Fritze Uta 
Published: December 2008

Abstract
With the advent of deep photometric surveys the use of photometric redshifts, obtained with a variety of techniques, has become more and more widespread. Giving access to galaxies with a wide range of luminosities out to high redshifts, these surveys include many faint galaxies with significantly subsolar metallicities.
We use our chemically consistent (CC) galaxy evolutionary synthesis code galev to produce a large grid of template spectral energy distributions (SEDs) for galaxies of spectral types E and Sa through Sd – one accounting in a CC way for the increasing initial metallicities of successive stellar generations, the other one for exclusively solar metallicities – for comparison.
We use our new photometric redshift code gazelle based on the comparison of observed and model SEDs. Comparing the photometric redshifts obtained using solar-metallicity templates when working on a catalogue of artificially created CC SEDs, typical for low-metallicity local late-type galaxies and for intrinsically low-luminosity, and hence low-metallicity, galaxies in the high-redshift universe, we find a significant bias resulting from this metallicity mismatch. This bias consists of a systematic underestimate of the photometric redshift by typically Δz≈ 0.1…0.2 until z≈ 1.2, depending on galaxy type, of distant, faint and low-metallicity galaxies if analysed with solar-metallicity templates.
Formation of the off-centre bar in the Large Magellanic Cloud: a collision with a dark satellite?
Authors: Bekki Kenji 
Published: December 2008

Abstract
Recent observations of the structural properties of the Large Magellanic Cloud (LMC) based on the Deep Near-Infrared Southern Sky Survey and Two Micron All-Sky Survey have revealed that the LMC has an off-centre bar even in the older stellar populations. Previous dynamical models including tidal interaction between the LMC, the Small Magellanic Cloud (SMC) and the Galaxy, however, did not reproduce the older off-centre bar so well. Here, we show that the off-centre bar can be formed if the LMC with an already-existing bar can collide with a low-mass Galactic subhalo as massive as ∼5 × 108M⊙ (roughly corresponding to a few per cent of the LMC mass). The simulated stellar distribution after the collision appears to show an ‘off-centre bar’, not because the centre of the bar significantly deviates from the dynamical centre of the LMC, but because the underlying stellar distribution of the disc is significantly asymmetric with respect to the centre of the bar. We discuss whether off-centre bars observed in Magellanic-type dwarf galaxies can be formed as a result of tidal interaction with low-mass haloes with no or little visible matter.
Gamma-ray burst optical afterglow and redshift selection effects: the learning curve effect at work
Authors: Coward D. M. 
Published: December 2008

Abstract
We show how the observed gamma-ray burst (GRB) optical afterglow (OA) and redshift distributions are changing in time from selection effects. For a subset of Swift triggered long-duration bursts, we show that the mean time taken to acquire spectroscopic redshifts for a GRB OA has evolved to shorter times. We identify a strong correlation between the mean time taken to acquire a spectroscopic redshift and the measured redshift. This correlation reveals that shorter response times favour smaller redshift bursts. This is compelling evidence for a selection effect that biases longer response times with relatively brighter high-redshift bursts. Conversely, for shorter response times, optically fainter bursts that are relatively closer are bright enough for spectroscopic redshifts to be acquired. This selection effect could explain why the average redshift, 〈z〉≈ 2.8 measured in 2005, has evolved to 〈z〉≈ 2, by mid 2008. Understanding these selection effects provides an important tool for separating the contributions of intrinsically faint bursts, those obscured by host galaxy dust and bursts not seen in the optical because their OAs are observed at late times. The study highlights the importance of rapid response telescopes capable of spectroscopy, and identifies a new redshift selection effect that has not been considered previously, namely the response time to measure the redshift.
COOKING CHARACTERISTICS OF CHEVON MARINATED WITH GINGER RHIZOME EXTRACT IN DIFFERENT STORAGE PERIODS
Authors: PAWAR V.D. , MACHEWAD G.M. , MULE B.D. 
Published: December 2008

ABSTRACT The biceps femoris muscles of 12‐month‐old Osmanabadi goats in the prerigor state were chilled for 24 h at 4 ± 1C, and then cut in 3 × 3 cm chunks and randomly divided into five groups. The chunks were marinated in ginger rhizome extract (GRE) at 1, 3, 5 and 7% along with 600 ppm of ascorbic acid, 2% sodium chloride and 0.5% sodium tripolyphosphate. The samples were packed in low‐density polyethylene bags and stored at refrigerated storage condition at 4 ± 1C for 1, 3, 5 and 7 days. After storage, samples were drawn and the cooking characteristics were determined following the related storage periods. The marination of chevon chunks at 5% GRE improved the cooking yield (83.5–87.9%), cooked density (0.86–0.94%) and gain in height (10.4–8.9%), whereas reduction in diameter (10.1–8.8%) and emulsion stability (12.5–10.44%) were lower than other levels of GRE at all periods of storage.PRACTICAL APPLICATIONSChevon is mostly stored at refrigeration conditions to increase its shelf life. However, there is not a limit of acceptability of chevon for the psychrophilic microorganisms that are important to estimate spoilage of refrigerated foods and also its texture. Marination of chevon with ginger rhizome extract at the 5% level along with 600 ppm of ascorbic acid, 2% sodium chloride and 0.5% sodium tripolyphosphate, and then storage at a refrigerated condition could prevent the spoilage and improve the texture. These levels of marination will be helpful in further studies to decide how long the chevon could be kept safe and tender.
A RESEARCH NOTE: EFFECT OF CITRIC ACID AND/OR ROSEMARY EXTRACT ON COLOR OF AN IRRADIATED BEEF MYOGLOBIN MODEL SYSTEM
Authors: STETZER ANDREA J. , NOVAKOFSKI JAN E. , BREWER M. SUSAN 
Published: December 2008

ABSTRACT To determine the effect of antioxidants and irradiation on meat color, myoglobin (Mb) was extracted from beef hearts. Mb was treated with one of four antioxidants (control, citric acid [CA], rosemary extract [RE] or combination of citric acid and rosemary extract [CA/RE]) and irradiated at 0.00 (Control), 0.50, 0.75, 1.00, 1.25, 1.50, 1.75 and 2.00 kGy. Samples were then evaluated for thiobarbituric reactive substances, pH, L*, a*and b*values, hue angles, and Chroma. RE‐ and CA‐containing samples had the highest postirradiation L*, a*and b*values, indicating they were lighter, redder and more yellow than controls. In terms of hue angles, all samples treated with antioxidants were much closer to the true red axis (a* = 0) of the CIE color space, both before and after irradiation, than was the control. The only color attribute affected by irradiation dose was L*value. Samples irradiated at 2.0 kGy were significantly lighter (L* = 5.27) than samples that had not been irradiated (L* = 1.28).PRACTICAL APPLICATIONSIrradiation is an effect method for extending the shelf life and improving the safety of fresh meat products; however, it can cause undesirable color changes at the surface of the meat, which appear to be the result of oxidative processes – therefore, reducing oxidation could effectively reduce color change. Studying pigment preservation is difficult in intact muscle tissue, so a myoglobin model system was developed for this purpose. Natural antioxidants were evaluated in this system. Rosemary extract and citric acid maintained color lightness and redness. Surface application of these antioxidants has the potential to preserve red meat color during irradiation.
EFFECT OF DIFFERENT FATS ON THE QUALITY OF GOAT MEAT PATTIES INCORPORATED WITH FULL‐FAT SOY PASTE
Authors: DAS ARUN K. , ANJANEYULU A.S.R. , THOMAS RAJENDRAN , KONDAIAH N. 
Published: December 2008

ABSTRACT Effect of different fats such as goat fat, chicken fat, combination of goat and chicken fat and refined mustard oil (RMO) were evaluated in goat meat patties (GMPs). Patties with 10% RMO contributed significantly (P < 0.05) better emulsion stability compared with others. There were no significant effects of different fats on physicochemical and textural attributes of patties. Patties with RMO had significantly (P < 0.05) lower cholesterol content than other groups. GMPs with RMO, chicken fat and chicken and goat fat combination rated higher for all sensory attributes than patties with goat fat, which had significantly (P < 0.05) higher mouth coating and lower overall acceptability. Flavor and overall acceptability were higher in patties with chicken fat. Histological study showed improper dispersion of goat fat in continuous phase of meat protein matrix (emulsion) compared with others.PRACTICAL APPLICATIONSUtilization of hard fats from goat, sheep and buffalo in emulsion‐based meat products decreases emulsion stability because of its poor dispersibility, and consequently its cooking yield. Goat fat also contributes to a smeary and greasy mouth‐coating problem and reduces the palatability of meat products. Alternatively, chicken fat disperses well in meat emulsion because of its high unsaturation and enhances the flavor of the products. However, the efficient utilization of goat fat is essential to support an economical goat meat production system and for developing meat products. The present study showed successful utilization of goat fat when combined with chicken fat, and the products had similar sensory attributes and acceptability as in meat products with chicken fat and refined mustard oil. This study would also help in better use of excess fat from spent hens in other meat products.
THE EFFECT OF RACTOPAMINE AND INTRAMUSCULAR FAT CONTENT ON SENSORY ATTRIBUTES OF PORK FROM PIGS OF SIMILAR GENETICS
Authors: RINCKER P.J. , KILLEFER J. , MATZAT P.D. , CARR S.N. , MCKEITH F.K. 
Published: December 2008

ABSTRACT The objective of this research was to determine how marbling influences sensory properties of pork. Fresh boneless pork loins were collected from 229 barrows of the same genetic line over a 2‐day period from a commercial slaughter facility. Live phase treatments included a control diet and the control diet supplemented with ractopamine (RAC) at 5 ppm for the final 28 days. Multiple 2.54‐cm chops were cut for determination of proximate composition, cook loss, Warner–Bratzler shear force and sensory analysis. RAC minimally affected pH and objective color, but had no effect on other pork quality measurements. Additionally, the relationship between extractable lipid and sensory properties or shear force was weak. These results suggest that the level of intramuscular fat has little to do with the eating quality in this population of pigs. PRACTICAL APPLICATIONSThe interest in highly marbled pork is based upon historical research that indicated increased marbling was beneficial to shear force values and sensory properties. Our research demonstrates that within a single genetic line, marbling does not dramatically affect sensory properties. Research of this type will help guide both consumers and the pork industry in a positive direction to determine factors that affect palatability and ultimately consumer satisfaction.
THE INFLUENCE OF POLYPHOSPHATE MARINATION ON SIMMENTAL BEEF SHEAR VALUE AND ULTRASTRUCTURE
Authors: XU SHU QIN , ZHOU GUANG HONG , PENG ZENG QI , ZHAO LI YAN , YAO RUI 
Published: December 2008

ABSTRACT The beef semitendinosus muscles were marinated for 1, 2 or 3 days with every polyphosphate at concentration of 1, 3 and 5%. Disodium dihydrogen pyrophosphate significantly increased (P < 0.01) soluble collagen content compared with the other polyphosphates; tetrosodium pyrophosphate (TSPP) and sodium hexametaphosphate (SHMP) disrupted myofibrillar structure completely; Z‐disks disappeared under transmission electron microscope (TEM); and myofibril bundles collapsed together. Sodium tripolyphosphate (STPP) disrupted myofibrillar structure as well, but Z‐disks were still perceptible under TEM. TSPP dissolved perimysium into collagen fibers and collagen fibrils, which arranged loosely and looked like dispersed silk. Perimysium was separated into collagen fibers and collagen fibrils by STPP and SHMP, but collagen fibrils were in close contact with each other. Polyphosphates all decreased shear force significantly compared with controls (P < 0.05).PRACTICAL APPLICATIONSThe tenderness and juiciness of meat are the most important focus of consumers. Food additives, especially polyphosphates, are generally added into fresh retail cuts as well as further processed products to improve water‐holding capacity and tenderness by meat industries. The article compared the different effects of polyphosphates and the effect of concentration on the ultrastructure and shear force of meat samples, thereby offering a theoretic guidance for the practical application of polyphosphates.
THE EFFECT OF ADDITION OF HAZELNUT OIL ON SOME QUALITY CHARACTERISTICS OF TURKISH FERMENTED SAUSAGE (SUCUK)
Authors: ILIKKAN HANDE , ERCOŞKUN HÜDAYI , VURAL HALIL , ŞAHİN EKIN 
Published: December 2008

ABSTRACT The effects on chemical and physical quality of the addition of beef fat with hazelnut oil were studied in sucuk. Two sucuk formulations were prepared by the addition of 2.5 and 5% hazelnut addition in which 11.11 and 20% of beef fat was substituted with hazelnut oil. The addition of hazelnut oil increased total fat of the product that affected the chemical, physical and sensorial characteristics of products. Added hazelnut oil decreased protein content but increased free fatty acids and thiobarbituric acid reactive substances values. The formulation with 2.5% hazelnut oil, corresponding to 11.11% substitution of beef fat with hazelnut oil, was judged as similar to control. PRACTICAL APPLICATIONSThe results suggest that the addition of hazelnut oil in the production of sucuk could give a healthier option to consumers. This study showed that substitution of animal fat with hazelnut oil in fermented sausages is a useful application to develop a functional fermented meat product. Additionally, this study indicated that the hazelnut oil was found to be a good oil in fermented sausage and opened the door for new research with a different nut.
CHARACTERISTICS OF BEEF PATTIES USING OKARA POWDER
Authors: TURHAN SADETTIN , TEMIZ HASAN , SAGIR INCI 
Published: December 2008

ABSTRACT Four different levels of okara powder (2.5, 5.0, 7.5 and 10%) were used to obtain beef patties that were compared with controls with 10 and 20% fat. Okara addition affected some quality parameters of beef patties. Although the protein, fat, ash and carbohydrate contents of raw beef patties increased by the addition of okara, moisture content decreased. The same trends (except protein content) were observed after cooking. The addition of okara reduced the cholesterol content by about 2–28% for raw beef patties and 6–23% for cooked beef patties. However, addition of okara increased the energy values for raw and cooked beef patties with respect to control with 10% fat. The WHC, cook loss and shrinkage of beef patties improved by the addition of okara. The addition of okara increased the pH, L*and b*values of raw beef patties, but did not affect a*value. The effect of okara on the sensory properties was statistically significant and the overall acceptability scores of samples decreased after more than 7.5% okara powder addition. According to these results, addition of okara powder up to 7.5% can be recommended as an extender in beef patties production to improving certain quality parameters.PRACTICAL APPLICATIONSOkara is an abundant by‐product of the soy and tofu industries and contains valuable components, including proteins, lipids, fibers and isoflavonoids. The addition of okara powder to beef patties reduces the cholesterol content and improves WHC, cook loss, shrinkage and sensory quality of the products. Okara powder can be added up to 7.5% for the production of patties.