300 research outputs found
Cosmic Star Formation History to z=1 from a Narrow Emission Line Selected Tunable Filter Survey
We report the results of a deep 3D imaging survey of the Hubble Deep Field
North using the Taurus Tunable Filter and the William Herschel Telescope. This
survey was designed to search for new line emitting populations of objects
missed by other techniques and to measure the cosmic star-formation rate
density from a line-selected survey. We observed in three contiguous sequences
of narrow band slices in the 7100, 8100 and 9100A regions of the spectrum,
corresponding to a cosmological volume of up to 1000 Mpc^3 at z=1, down to a
flux limit of 2x 10^-17 ergs cm^-2 s^-1. The survey is deep enough to be highly
complete for low line luminosity galaxies. Cross-matching with existing
spectroscopy in the field results in a small line-luminosity limited sample,
with very highly redshift identification completeness containing seven [OII],
Hbeta and Halpha emitters over the redshift range 0.3 - 0.9. Treating this as a
direct star-formation rate selected sample we estimate the star-formation
history of the Universe to z=1. We find no evidence for any new population of
line emitting objects contributing significantly to the cosmological
star-formation rate density. Rather from our complete narrow-band sample we
find the star-formation history is consistent with earlier estimates from
broad-band imaging surveys and other less deep line-selected surveys.Comment: 12 pages, 3 figures. ApJ in press (Dec 2004
In-stent thrombosis after 68 months of implantation inspite of continuous dual antiplatelet therapy: a case report
Lately, there has been an increased incidence of late stent thrombosis; especially following Drug eluting stent (DES) implantation. Several factors are associated with an increased risk of stent thrombosis, including the procedure itself, patient and lesion characteristics, stent design, and premature cessation of anti-platelet drugs. We present a case of late stent thrombosis (LST) following DES implantation after a period of 68 months, making it the longest reported case of LST reported in the literature, despite the use of dual anti-platelet therapy
The relevance of tissue angiotensin-converting enzyme: manifestations in mechanistic and endpoint data
Angiotensin-converting enzyme (ACE) is primarily localized (>90%) in various tissues and organs, most notably on the endothelium but also within parenchyma and inflammatory cells. Tissue ACE is now recognized as a key factor in cardiovascular and renal diseases. Endothelial dysfunction, in response to a number of risk factors or injury such as hypertension, diabetes mellitus, hypercholesteremia, and cigarette smoking, disrupts the balance of vasodilation and vasoconstriction, vascular smooth muscle cell growth, the inflammatory and oxidative state of the vessel wall, and is associated with activation of tissue ACE. Pathologic activation of local ACE can have deleterious effects on the heart, vasculature, and the kidneys. The imbalance resulting from increased local formation of angiotensin II and increased bradykinin degradation favors cardiovascular disease. Indeed, ACE inhibitors effectively reduce high blood pressure and exert cardio- and renoprotective actions. Recent evidence suggests that a principal target of ACE inhibitor action is at the tissue sites. Pharmacokinetic properties of various ACE inhibitors indicate that there are differences in their binding characteristics for tissue ACE. Clinical studies comparing the effects of antihypertensives (especially ACE inhibitors) on endothelial function suggest differences. More comparative experimental and clinical studies should address the significance of these drug differences and their impact on clinical events
Measurement of the cosmic ray spectrum above eV using inclined events detected with the Pierre Auger Observatory
A measurement of the cosmic-ray spectrum for energies exceeding
eV is presented, which is based on the analysis of showers
with zenith angles greater than detected with the Pierre Auger
Observatory between 1 January 2004 and 31 December 2013. The measured spectrum
confirms a flux suppression at the highest energies. Above
eV, the "ankle", the flux can be described by a power law with
index followed by
a smooth suppression region. For the energy () at which the
spectral flux has fallen to one-half of its extrapolated value in the absence
of suppression, we find
eV.Comment: Replaced with published version. Added journal reference and DO
Genomic rearrangements in BRCA1 and BRCA2: A literature review
Women with mutations in the breast cancer genes BRCA1 or BRCA2 have an increased lifetime risk of developing breast, ovarian and other BRCA-associated cancers. However, the number of detected germline mutations in families with hereditary breast and ovarian cancer (HBOC) syndrome is lower than expected based upon genetic linkage data. Undetected deleterious mutations in the BRCA genes in some high-risk families are due to the presence of intragenic rearrangements such as deletions, duplications or insertions that span whole exons. This article reviews the molecular aspects of BRCA1 and BRCA2 rearrangements and their frequency among different populations. An overview of the techniques used to screen for large rearrangements in BRCA1 and BRCA2 is also presented. The detection of rearrangements in BRCA genes, especially BRCA1, offers a promising outlook for mutation screening in clinical practice, particularly in HBOC families that test negative for a germline mutation assessed by traditional methods
Natational Dress: Functionality, Fashion and the Fracturing of Separate Spheres in Victorian Britain
In 1873, The Englishwoman's Domestic Magazine extolled the values of swimming for women and gave advice on the best form of bathing dress, one which preserved modesty and met the demands of contemporary fashion. This essentially impractical type of bathing outfit has been the subject of much of the historiography surrounding female swimming costumes but it was not the only swimming dress on show during the “long” Victorian period. The women of all classes who participated in more serious swimming required something functional rather than fashionable while working-class professional natationists, who appeared regularly in water shows throughout the country, wore attire that combined functionality, tight to the body while allowing freedom of movement, with public appeal, a critical consideration for female exhibitors. Their activities and costumes challenged prevailing notions of “separate spheres” and this paper explores Victorian aquatic dress in the context of class, gender and social space
Altered Insulin Receptor Signalling and β-Cell Cycle Dynamics in Type 2 Diabetes Mellitus
Insulin resistance, reduced β-cell mass, and hyperglucagonemia are consistent features in type 2 diabetes mellitus (T2DM). We used pancreas and islets from humans with T2DM to examine the regulation of insulin signaling and cell-cycle control of islet cells. We observed reduced β-cell mass and increased α-cell mass in the Type 2 diabetic pancreas. Confocal microscopy, real-time PCR and western blotting analyses revealed increased expression of PCNA and down-regulation of p27-Kip1 and altered expression of insulin receptors, insulin receptor substrate-2 and phosphorylated BAD. To investigate the mechanisms underlying these findings, we examined a mouse model of insulin resistance in β-cells – which also exhibits reduced β-cell mass, the β-cell-specific insulin receptor knockout (βIRKO). Freshly isolated islets and β-cell lines derived from βIRKO mice exhibited poor cell-cycle progression, nuclear restriction of FoxO1 and reduced expression of cell-cycle proteins favoring growth arrest. Re-expression of insulin receptors in βIRKO β-cells reversed the defects and promoted cell cycle progression and proliferation implying a role for insulin-signaling in β-cell growth. These data provide evidence that human β- and α-cells can enter the cell-cycle, but proliferation of β-cells in T2DM fails due to G1-to-S phase arrest secondary to defective insulin signaling. Activation of insulin signaling, FoxO1 and proteins in β-cell-cycle progression are attractive therapeutic targets to enhance β-cell regeneration in the treatment of T2DM
Efficacy and safety of venous angioplasty of the extracranial veins for multiple sclerosis. Brave dreams study (brain venous drainage exploited against multiple sclerosis): study protocol for a randomized controlled trial
Consensus guidelines for the use and interpretation of angiogenesis assays
The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference
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