7,064 research outputs found
Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (Mid-Atlantic): Alewife/Blueback Herring
This profile covers life history
and environmental requirements of
both alewife (Alosa pseudoharengus)
and blueback herring (Alosa aestivalis),
since their distribution is
overlapping and their morphology,
ecological role, and environmental
requirements are similar.
The alewife is
an anadromous species found in
riverine, estuarine, and Atlantic
coastal habitats, depending on
life cycle stage, from Newfoundland
(Winters et al. 1973) to
Soutn Carolina (Berry 1964).
Landlocked populations are i n the
Great Lakes, Finger Lakes, and
many other freshwater lakes
(Bigelow and Sch roeder 1953;
Scott and Crossman 1973). The
blueback herring is an anadromous
species found in riverine,
estuarine, and Atlantic coastal
habitats, depending on life stage
cycle, from Nova Scotia to the
St. Johns River, Florida (Hildebrand
1963
Perivascular adipose tissue as a relevant fat depot for cardiovascular risk in obesity
Obesity is associated with increased risk of premature death, morbidity, and mortality from several cardiovascular diseases (CVDs), including stroke, coronary heart disease (CHD), myocardial infarction, and congestive heart failure. However, this is not a straightforward relationship. Although several studies have substantiated that obesity confers an independent and additive risk of all-cause and cardiovascular death, there is significant variability in these associations, with some lean individuals developing diseases and others remaining healthy despite severe obesity, the so-called metabolically healthy obese. Part of this variability has been attributed to the heterogeneity in both the distribution of body fat and the intrinsic properties of adipose tissue depots, including developmental origin, adipogenic and proliferative capacity, glucose and lipid metabolism, hormonal control, thermogenic ability, and vascularization. In obesity, these depot-specific differences translate into specific fat distribution patterns, which are closely associated with differential cardiometabolic risks. The adventitial fat layer, also known as perivascular adipose tissue (PVAT), is of major importance. Similar to the visceral adipose tissue, PVAT has a pathophysiological role in CVDs. PVAT influences vascular homeostasis by releasing numerous vasoactive factors, cytokines, and adipokines, which can readily target the underlying smooth muscle cell layers, regulating the vascular tone, distribution of blood flow, as well as angiogenesis, inflammatory processes, and redox status. In this review, we summarize the current knowledge and discuss the role of PVAT within the scope of adipose tissue as a major contributing factor to obesity-associated cardiovascular risk. Relevant clinical studies documenting the relationship between PVAT dysfunction and CVD with a focus on potential mechanisms by which PVAT contributes to obesity-related CVDs are pointed out
Maxwell-Chern-Simons vortices in a CPT-odd Lorentz-violating Higgs Electrodynamics
We have studied BPS vortices in a CPT-odd and Lorentz-violating
Maxwell-Chern-Simons-Higgs (MCSH) electrodynamics attained from the dimensional
reduction of the Carroll-Field-Jackiw-Higgs model. The Lorentz-violating
parameter induces a pronounced behavior at origin (for the magnetic/electric
fields and energy density) which is absent in the MCSH vortices. For some
combination of the Lorentz-violating coefficients there always exist a
sufficiently large winding number such that for all
the magnetic field flips its signal, yielding two well defined regions with
opposite magnetic flux. However, the total magnetic flux remains quantized and
proportional to the winding number.Comment: Revtex style, 8 page
MODELLING OF HYDRODYNAMICS AROUND AN IMPERMEABLE BREAKWATER: COMPARISON BETWEEN PHYSICAL AND SPH NUMERICAL MODELING
This work presents the new developments and the validation of a Smoothed Particle Hydrodynamics (SPH) numerical model used in the National Laboratory of Civil Engineering (Laboratório Nacional de Engenharia Civil - LNEC) for studies in coastal engineering processes. Although the model requires a high CPU time, it proved to be very promising in the simulation of complex flows, such as the wave-structure interaction and the wave breaking phenomenon. For the SPH model validation, physical modeling tests were performed in one LNEC’s flume to study the interaction between an impermeable structure and an incident regular wave. The comparison between numerical and experimental results, i.e. free surface elevation, overtopping volume and pressure, shows the good accuracy of the SPH model to reproduce the various phenomena involving on the wave propagation and interaction with the structure, namely the wave breaking, the wave overtopping and the pressure field on the structure
The Effect of a positive cosmological constant on the bounce of Loop Quantum Cosmology
We provide an analytical solution to the quantum dynamics of a flat
Friedmann-Lema\^itre- Robertson-Walker model with a massless scalar field in
the presence of a small and positive cosmological constant, in the context of
Loop Quantum Cosmology. We use a perturbative treatment with respect to the
model without a cosmological constant, which is exactly solvable. Our solution
is approximate, but it is precisely valid at the high curvature regime where
quantum gravity corrections are important. We compute explicitly the evolution
of the expectation value of the volume. For semiclassical states characterized
by a Gaussian spectral profile, the introduction of a positive cosmological
constant displaces the bounce of the solvable model to lower volumes and to
higher values of the scalar field. These displacements are state dependent, and
in particular, they depend on the peak of the Gaussian profile, which measures
the momentum of the scalar field. Moreover, for those semiclassical states, the
bounce remains symmetric, as in the vanishing cosmological constant case.
However, we show that the behavior of the volume is more intricate for generic
states, leading in general to a non-symmetric bounce.Comment: 17 pages, 3 figures, v2: matches published versio
Dakin's Solution in the Treatment of Severe Diabetic Foot Infections
Acute necrotising diabetic foot (DF) infections are common, costly, and do not infrequently result in debilitating major lower-extremity amputations. Dakin's solution is a long-standing topical antiseptic that has shown benefit in this clinical setting, but its use is undermined by a presumed risk of cytotoxicity. In this single-centre case series, we retrospectively evaluated 24 patients with severe necrotising DF infections treated with a cyclical instillation of Dakin's solution at a referral multidisciplinary DF unit. Most patients achieved favourable outcomes in infection control and limb salvage, with only one patient (4.2%) requiring a major (at or above-the-ankle) amputation. The mean time to complete or near-complete wound granulation was 5.4 weeks. Of the 12 patients who completed 12 or more months of longitudinal follow up, only 2 (12.2%) had a wound recurrence. In this severe DF infection patient cohort, Dakin's solution led to a clinically meaningful improvement. No remarkable impairment in the wound-healing process was observed.info:eu-repo/semantics/publishedVersio
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