2,689 research outputs found
Functional Convergence of Linear Processes with Heavy-Tailed Innovations
We study convergence in law of partial sums of linear processes with
heavy-tailed innovations. In the case of summable coefficients necessary and
sufficient conditions for the finite dimensional convergence to an
-stable L\'evy Motion are given. The conditions lead to new, tractable
sufficient conditions in the case . In the functional setting we
complement the existing results on -convergence, obtained for linear
processes with nonnegative coefficients by Avram and Taqqu (1992) and improved
by Louhichi and Rio (2011), by proving that in the general setting partial sums
of linear processes are convergent on the Skorokhod space equipped with the
topology, introduced by Jakubowski (1997).Comment: 39 pages; revised version of arxiv 1209.114
An exceptional X-ray view of the young open cluster NGC 6231: what XMM-Newton has taught us
Considered as the core of the Sco OB1 association, the young open cluster NGC
6231 harbours a rich O-type star population. In 2001, the XMM-Newton satellite
targeted the cluster for a nominal duration of about 180 ks. Thanks to the
detector sensitivity, the EPIC cameras provided an unprecedented X-ray view of
NGC 6231, revealing about 600 point-like sources. In this contribution, we
review the main results that have been obtained thanks to this unprecedented
data set. Concerning the O-type stars, we present the latest developments
related to the so-called 'canonical' Lx-Lbol relation. The dispersion around
this relation might actually be much smaller than previously thought. In our
data set, the sole mechanism that yields a significant deviation from this
scheme is wind interaction. It is also the sole mechanism that induces a
significant variation of the early-type star X-ray flux. In a second part of
this contribution, we probe the properties of the optically faint X-ray
sources. Most of them are believed to be low mass pre-main sequence stars.
Their analysis provides direct insight into the star formation history of the
cluster.Comment: 6 pages, 5 figures, to appear in "The X-Ray Universe 2005", ESA
Symposium held at El Escorial, Madrid (Spain), 26-30 Sep 200
Isolated IgG4-related sclerosing cholangitis mimicking hilar cholangiocarcinoma: a case report of a challenging disease
IgG4-related disease (IgG4-RD) has recently attracted attention worldwide; however, its diagnosis still remains challenging. It is an immune-mediated multisystem disease affecting a wide range of organs in the human body. Even though it's uncommon, IgG4-sclerosing cholangitis, which is a biliary manifestation of IgG4-RD, can happen without pancreatic involvement. Here, we report a case of a patient with imaging features typical of hilar cholangiocarcinoma, which eventually turned out to be IgG4 sclerosing cholangitis
An XMM-Newton view of the young open cluster NGC 6231 -- II. The OB star population
In this second paper, we pursue the analysis of the 180 ks XMM-Newton
campaign towards the young open cluster NGC 6231 and we focus on its rich OB
star population. We present a literature-based census of the OB stars in the
field of view with more than one hundred objects, among which 30% can be
associated with an X-ray source. All the O-type stars are detected in the X-ray
domain as soft and reasonably strong emitters. In the 0.5-10.0 keV band, their
X-ray luminosities scale with their bolometric luminosities as . Such a scaling law holds in
the soft (0.5-1.0 keV) and intermediate (1.0-2.5 keV) bands but breaks down in
the hard band. While the two colliding wind binaries in our sample clearly
deviate from this scheme, the remaining O-type objects show a very limited
dispersion (40% or 20% according to whether `cool' dwarfs are included or not),
much smaller than that obtained from previous studies. At our detection
threshold and within our sample, the sole identified mechanism that produces
significant modulations in the O star X-ray emission is related to wind
interaction. The intrinsic X-ray emission of non-peculiar O-type stars seems
thus constant for a given star and the level of its X-ray emission is
accurately related to the its luminosity or, equivalently, to its wind
properties. Among B-type stars, the detection rate is only about 25% in the
sub-type range B0-B4 and remains mostly uniform throughout the different
sub-populations while it drops significantly at later sub-types. The associated
X-ray spectra are harder than those of O-type stars. Our analysis points
towards the detected emission being associated with a physical PMS companion
>... [see paper for the complete abstract]Comment: 21 pages, 14 figures, Table 2 and Figs 2 to 5 will be available
through the CDS only, accepted for publication by MNRAS, Fig 1 not included
in the present preprint because of size limitation
The Struve-Sahade effect in the optical spectra of O-type binaries I. Main-sequence systems
We present a spectroscopic analysis of four massive binary systems that are
known or are good candidates to display the Struve-Sahade effect (defined as
the apparent strengthening of the secondary spectrum of the binary when the
star is approaching, and the corresponding weakening of the lines when it is
receding).
We use high resolution optical spectra to determine new orbital solutions and
spectral types of HD 165052, HD 100213, HD 159176 and DH Cep. As good knowledge
of the fundamental parameters of the considered systems is necessary to examine
the Struve-Sahade effect. We then study equivalent width variations in the
lines of both components of these binaries during their orbital cycle.
In the case of these four systems, variations appear in the equivalent widths
of some lines during the orbital cycle, but the definition given above can any
longer be valid, since it is now clear that the effect modifies the primary
spectrum as much as the secondary spectrum. Furthermore, the lines affected,
and the way in which they are affected, depend on the considered system. For at
least two of them (HD 100213 and HD 159176) these variations probably reflect
the ellipsoidal variable nature of the system.Comment: 12 pages, 20 figures, in press A&
Barriers and Facilitators to Service Utilization for People with Dementia and Their Caregivers
According to the CDC, there were 5.2 million Americans living with Alzheimer’s disease in 2013 (CDC 2013). That number is expected to nearly triple in 2050 as the baby boomer generation reaches retirement age. Underutilization of services is something experienced by many demographics and is a considerable issue for individuals with dementia. This study sought to uncover factors correlated with underutilization of services for people with dementia through both a literature review and sit-down interviews with three healthcare professionals. Results indicated that cultural, financial, attitudinal and knowledge barriers exist for PwD (people with dementia) and their caregivers and may interfere with their ability to seek the help they need. By uncovering these barriers and proposing potential solutions to these problems, issues related to health service utilization can be minimized and eventually overcome.B.S. (Bachelor of Science
The Usage of Edible Additives with Different Gluten Quality in Baking Products
One of the dominating factors in the foods quality besides the wheat quality,grinding and baking technology,is also the impact of edible additives in these products.These agents are nothing but chemical base products,that change the physical and rheological properties of baking products with the help of oxidation and reduction reactions placed in dough.The structures and quantitative formations of gluten proteins define dough qualities for cakes,biscuits and wafers.Reductants are substances,which soften gluten,weakening its links.Reductants react with disulfide SS in dough.Their impact is the reduction of the general molecular weight of the gluten proteins aggregates.The usage of reductants leads in the incensement of dough volume.The fixed gas inside the dough can develop a soft dough. The first scale of the reaction is the interaction of reductants with the gluten proteins. This reaction is an exchange SH/SS that releases a protein unit and leaves a SS link between protein and reductant. This SS part can interact with the reductant,leaving the second protein group free and giving the oxidized form to it.The most used reductants are L-Cysteins and Metabisulfite of Sodium. From the evidences made, results that the usage of these reductants leads to an advanced incensement of the dough and to a great form of the ultimate product. Based on our research for produced wheat’s in our country and those which are imported, for a certain flour radius and choice, the research is done among the evolution of redox agents interaction based upon the production of products like cakes,biscuits,wafers etc
Women Gathered on Flat Rooftops and Thumprints in Black Coffee
Women Gathered on Flat Rooftops and Thumbprints in Black Coffee is a creative dissertation that examines the lives of Arab women living in Jordan and Arab immigrants living in the United States. The first portion of the dissertation, Women Gathered on Flat Rooftops is an excerpt from the early portion of the novel by the same name. These first 53 pages provide the background of the characters and highlights aspects that are culturally specific to the women of the stories. For example, issues of arranged marriages, funeral practices, women’s custody rights are all illustrated through these early stories. The early portion of the novel provides the situation as well as the structure of the overall story. While the situations that the women in this portion of the novel experience are specific to contemporary Amman, Jordan, the fundamental concerns of women addressed in this novel are cross-cultural.
The second portion of the dissertation, Thumbprints in Black Coffee is comprised of poems that reveal the Arab-American immigrant experience. Most of the poems included in this section tell the story of various members of the author’s own family and demonstrate how Arab-Americans are torn between two worlds. The longer poems were conceived from interviews with the author’s father and aunts who were raised in Palestine and Jordan, but have lived most of their adult lives in the U.S
- …