22 research outputs found

    Higher Dimensional Cylindrical or Kasner Type Electrovacuum Solutions

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    We consider a D dimensional Kasner type diagonal spacetime where metric functions depend only on a single coordinate and electromagnetic field shares the symmetries of spacetime. These solutions can describe static cylindrical or cosmological Einstein-Maxwell vacuum spacetimes. We mainly focus on electrovacuum solutions and four different types of solutions are obtained in which one of them has no four dimensional counterpart. We also consider the properties of the general solution corresponding to the exterior field of a charged line mass and discuss its several properties. Although it resembles the same form with four dimensional one, there is a difference on the range of the solutions for fixed signs of the parameters. General magnetic field vacuum solution are also briefly discussed, which reduces to Bonnor-Melvin magnetic universe for a special choice of the parameters. The Kasner forms of the general solution are also presented for the cylindrical or cosmological cases.Comment: 16 pages, Revtex. Text and references are extended, Published versio

    Localization and broadband follow-up of the gravitational-wave transient GW150914

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    A gravitational-wave (GW) transient was identified in data recorded by the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) detectors on 2015 September 14. The event, initially designated G184098 and later given the name GW150914, is described in detail elsewhere. By prior arrangement, preliminary estimates of the time, significance, and sky location of the event were shared with 63 teams of observers covering radio, optical, near-infrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities. In this Letter we describe the low-latency analysis of the GW data and present the sky localization of the first observed compact binary merger. We summarize the follow-up observations reported by 25 teams via private Gamma-ray Coordinates Network circulars, giving an overview of the participating facilities, the GW sky localization coverage, the timeline, and depth of the observations. As this event turned out to be a binary black hole merger, there is little expectation of a detectable electromagnetic (EM) signature. Nevertheless, this first broadband campaign to search for a counterpart of an Advanced LIGO source represents a milestone and highlights the broad capabilities of the transient astronomy community and the observing strategies that have been developed to pursue neutron star binary merger events. Detailed investigations of the EM data and results of the EM follow-up campaign are being disseminated in papers by the individual teams

    Observation of Gravitational Waves from a Binary Black Hole Merger

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    On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0 × 10−21. It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203 000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410þ160 −180 Mpc corresponding to a redshift z ¼ 0.09þ0.03 −0.04 . In the source frame, the initial black hole masses are 36þ5 −4M⊙ and 29þ4 −4M⊙, and the final black hole mass is 62þ4 −4M⊙, with 3.0þ0.5 −0.5M⊙c2 radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger

    Localization and broadband follow-up of the gravitational-wave transient GW150914

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    A gravitational-wave transient was identified in data recorded by the Advanced LIGO detectors on 2015 September 14. The event candidate, initially designated G184098 and later given the name GW150914, is described in detail elsewhere. By prior arrangement, preliminary estimates of the time, significance, and sky location of the event were shared with 63 teams of observers covering radio, optical, near-infrared, X-ray, and gamma-ray wavelengths with ground- and space-based facilities. In this Letter we describe the low-latency analysis of the gravitational wave data and present the sky localization of the first observed compact binary merger. We summarize the follow-up observations reported by 25 teams via private Gamma-ray Coordinates Network Circulars, giving an overview of the participating facilities, the gravitational wave sky localization coverage, the timeline and depth of the observations. As this event turned out to be a binary black hole merger, there is little expectation of a detectable electromagnetic signature. Nevertheless, this first broadband campaign to search for a counterpart of an Advanced LIGO source represents a milestone and highlights the broad capabilities of the transient astronomy community and the observing strategies that have been developed to pursue neutron star binary merger events. Detailed investigations of the electromagnetic data and results of the electromagnetic follow-up campaign will be disseminated in the papers of the individual teams

    thyroid cartilage, cricoid cartilage, sex and stature: an autopsy study

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    Background/Aim. Cartilage structures, such as the thyroid cartilage and cricoid cartilage, which are readily accessible and easy to remove from the surrounding soft tissues, can be useful in the identification of a dismembered corpse. The present study investigates the relationship between anthropologic measurements of the thyroid and cricoid cartilages and sex and stature measurements.Methods. Included in the study were the thyroid and cricoid cartilages of 65 males and 26 females aged 18 years and above that underwent a medicolegal autopsy. The stature, anterior thyroid height, length of the thyroid lamina, thyroid angle, height of the cricoid arch and height of the cricoid lamina were measured in all cases,Results. With the exception of thyroid angle, all measurements in the thyroid cartilage and cricoid cartilage were greater in males than in females (p<0.001), The thyroid angle was greater in females (93.88 degrees +/- 10,39) than in males (76.08 degrees +/- 10.34) (p< 0.001). A discriminant function analysis showed that the measured parameters of the thyroid cartilage yielded an accuracy of 97.8%, those measured in the cricoid cartilage yielded an accuracy of 95.6%, and the model comprising all parameters measured in the thyroid and cricoid cartilages yielded an accuracy of 100% in sex estimation. For all cases, there was a moderate positive correlation between stature and all parameters except thyroid angle,Conclusion. The results of the present study show that anthropometric measurements of the thyroid and cricoid cartilage can be useful in sex estimation,C1 [Dereli, Ayse Kurtulus; Acar, Kemalettin; Kutlu, Erdi] Pamukkale Univ, Fac Med, Dept Forens Med, TR-20020 Denizli, Turkey.[Sahin, Beyza] Pamukkale Univ, Fac Med, Dept Biostat, Denizli, Turkey

    using 3D modeling techniques in computerized tomography

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    Sex determination is a major area of investigation in forensic anthropology. As technology has advanced, imaging methods such as computed tomography and magnetic resonance imaging are being investigated as alternatives to conventional forensic anthropological research techniques. This study aimed to investigate the suitability of three-dimensional (3D) modeling of volumetric cranial computed tomography (CCT) images for sex estimation from skull morphology. In this study, CCT angiography images from the Department of Radiology 2017 archives were used retrospectively, and 3D images were obtained after the reconstruction of 85 cases of CCT images. The sex-dependent morphological characteristics of the skull were evaluated by three blinded observers and scored on a scale of 1-5 points according to the "Standards for Data Collection from Human Skeletal Remains". The accurate sex estimation rates of the first, second and third observers were 91.8, 92.9 and 92.9%, respectively. The rate of accurate sex estimation for males was 98-100%, while this rate varied between 83.3-86.1% for females. Consistency in sex estimation between the three observers was 83.5%, with a Kappa value of 0.763 (z = 12.2; p = 0.0001*). The glabella was the most effective morphological trait used to estimate sex. The results of this study show that sex can be estimated from morphological features in volume-rendered CCT 3D images. Thus, sex can be estimated by digital images without the need for maceration processes, and the transfer of digital data in place of physical material will make it possible to gain expert opinions in forensic anthropology

    chromatography of bloodstains

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    This study aimed to determine haemoglobin A1c (HbA1c) levels in bloodstains shed on glass and fabric surfaces on specified test dates. Blood samples were taken from 26 patients (13 diabetic and 13 non-diabetic). Initial HbA1c levels were detected by using high-performance liquid chromatography (HPLC), and bloodstains were created on both cotton fabric and glass surfaces. Samples were processed at different ages (0, 7, 14, 28 and 56 days) by diluting distilled water and then measuring HbA1c levels by HPLC again. In all stains, HbA1c levels could be determined by using HPLC, but there was a moderate rise in accordance with the age of the stains. A statistically significant difference was found for bloodstains on clothes compared to those on glass surfaces. Receiver operating curve analysis found a sensitivity of 1.0 and specificity of 0.923 (cut-off 6.55) for glass surfaces on the seventh day; a sensitivity of 1.0, a specificity of 0.846 (cut-off 6.45) for clothes on the seventh day; a sensitivity of 1.0 and a specificity of 0.923 (cut-off 6.85) for clothes on the 56th day; and a sensitivity of 1.0 and a specificity of 0.846 (cut-off 7.55) for glass surfaces on the 56th day. In conclusion, this study found that HbA1c levels could be measured with high reliability from forensic bloodstains by using HPLC. Thus, in cases where DNA data banks cannot identify individuals, it would make sense to turn to those who have a medical history of diabetes among the suspects with the results of high HbA1c levels.C1 [Acar, Kemalettin; Kurtulus Dereli, Ayse; Zeybek, Volkan; Kutlu, Erdi] Pamukkale Univ, Fac Med, Dept Forens Med, TR-20020 Denizli, Turkey.[Avci, Esin; Demir, Suleyman] Pamukkale Univ, Fac Med, Dept Med Biochem, Denizli, Turkey.[Senol, Hande] Pamukkale Univ, Fac Med, Dept Biostat, Denizli, Turkey

    A GIS-based multi-criteria model for offshore wind energy power plants site selection in both sides of the Aegean Sea

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    Location selection for offshore wind farms is a major challenge for renewable energy policy, marine spatial planning, and environmental conservation. This selection constitutes a multi-criteria decision-making problem, through which parameters like wind velocity, water depth, shorelines, fishing areas, shipping routes, environmental protection areas, transportation, and military zones should be jointly investigated. The aim of the present study was thus to develop an integrated methodology for assessing the siting of bottom-fixed offshore wind farms in two different countries (with different legal, political, and socio/economic characteristics). Our methodology combined multi-criteria decision making methods and geographical information systems and was implemented in Cyclades (Greece) and in the sea area of İzmir region (Turkey). Experts used fuzzy sets and linguistic terms to achieve more consistent and independent rankings and results. In the Turkish region, the results showed that 519 km2 (10.23%) of the study area is suitable for offshore wind farms, while in the Greek region, only 289 km2 (3.22%) of the study area was found to be suitable. This spatial suitability analysis may contribute to provide some useful recommendations for the spatial marine planning at the regional scale, as well as for the preliminary assessment of new offshore wind farms in both countries.No sponso

    immunoreactivity in suicide: A preliminary study

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    Disorders of the serotonergic system are especially known to be present in the neurobiology of suicidal behavior. Studies investigating melatonin levels show that changes in pineal gland functions may also play a role in the pathogenesis of suicide. However, to our knowledge, there are no studies evaluating the activity of pinealocytes responsible for melatonin synthesis in suicide. This preliminary study aimed to investigate the relationship among pinealocyte, acetylserotonin O-methyltransferase (ASMT) immunoreactivity, and suicide. Samples of pineal gland, cerebrospinal fluid, blood, and urine were obtained from 21 suicide and 21 non-suicide cases on which medicolegal autopsies were performed. Expression of ASMT in human pineal gland was evaluated by immunohistochemical methods. A scoring system was used to define the anti-ASMT-positive staining in the sections. Enzyme-linked immunosorbent assays were employed to assess serum and cerebrospinal fluid melatonin levels and blood and urine noradrenaline levels. The ASMT-immunopositive pinealocyte count was observed to be lower in suicide cases compared to the non-suicide cases. With the exception of two cases (with moderate staining), all graded scores were 3 (strong staining) in non-suicide group, whereas scores were 1 (mild staining) or 2 (moderate staining) in the suicide group. Melatonin levels in the blood were lower among the suicide victims. These results support decreased pineal gland activity in suicide. However, further studies are needed to assess whether these changes are related to a psychiatric disorder
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