368 research outputs found
Compound surface-plasmon-polariton waves guided by a thin metal layer sandwiched between a homogeneous isotropic dielectric material and a periodically multilayered isotropic dielectric material
Multiple p- and s-polarized compound surface plasmon-polariton (SPP) waves at
a fixed frequency can be guided by a structure consisting of a metal layer
sandwiched between a homogeneous isotropic dielectric (HID) material and a
periodic multilayered isotropic dielectric (PMLID) material. For any thickness
of the metal layer, at least one compound SPP wave must exist. It possesses the
p-polarization state, is strongly bound to the metal/HID interface when the
metal thickness is large but to both metal/dielectric interfaces when the metal
thickness is small. When the metal layer vanishes, this compound SPP wave
transmutes into a Tamm wave. Additional compound SPP waves exist, depending on
the thickness of the metal layer, the relative permittivity of the HID
material, and the period and the composition of the PMLID material. Some of
these are p polarized, the others being s polarized. All of them differ in
phase speed, attenuation rate, and field profile, even though all are excitable
at the same frequency. The multiplicity and the dependence of the number of
compound SPP waves on the relative permittivity of the HID material when the
metal layer is thin could be useful for optical sensing applications.Comment: 17 page
Compound surface-plasmon-polariton waves guided by a thin metal layer sandwiched between a homogeneous isotropic dielectric material and a structurally chiral material
Multiple compound surface plasmon-polariton (SPP) waves can be guided by a
structure consisting of a sufficiently thick layer of metal sandwiched between
a homogeneous isotropic dielectric (HID) material and a dielectric structurally
chiral material (SCM). The compound SPP waves are strongly bound to both
metal/dielectric interfaces when the thickness of the metal layer is comparable
to the skin depth but just to one of the two interfaces when the thickness is
much larger. The compound SPP waves differ in phase speed, attenuation rate,
and field profile, even though all are excitable at the same frequency. Some
compound SPP waves are not greatly affected by the choice of the direction of
propagation in the transverse plane but others are, depending on metal
thickness. For fixed metal thickness, the number of compound SPP waves depends
on the relative permittivity of the HID material, which can be useful for
sensing applications
May Adiponectin be considered as a Novel Cardiometabolic Biomarker?
This study was designed to evaluate the interaction between total adiponectin (ADPN)
and metabolic syndrome (MetS) on cardiac changes in 135 subjects with and without
MetS, subgrouped according to normal or low ADPN. Left ventricular internal diameter
(LVID/h), LV mass (LVM), LVM index (LVMI), interventricular septal thickness (IVST),
relative wall thickness (RWT) and LV ejection fraction (EF) by echocardiography and
diastolic parameters, by pulsed-wave Doppler were calculated.
BMI, LVM, LVMI, LVID/h, IVST and RWT values were significantly (p<0.05) higher in
both groups with low ADPN. Prevalence of left ventricular hypertrophy (p<0.001) and
coronary artery disease (p<0.01) was significantly higher in both low ADPN groups.
LVMI correlated directly with BMI (p<0.001), (p<0.001), MetS (p<0.001) and inversely
with ADPN (p<0.0001). ADPN and BMI resulted independently associated with LVMI.
In conclusion, our data suggest that hypoadiponectinemia might be considered a novel
“cardiometabolic biomarker”. Accordingly, circulating ADPN might become a new
target in the management of cardiometabolic syndrome
Design of decorated self-assembling peptide hydrogels as architecture for mesenchymal stem cells
Hydrogels from self-assembling ionic complementary peptides have been receiving a lot of interest from the scientific community as mimetic of the extracellular matrix that can offer three-dimensional supports for cell growth or can become vehicles for the delivery of stem cells, drugs or bioactive proteins. In order to develop a 3D "architecture" for mesenchymal stem cells, we propose the introduction in the hydrogel of conjugates obtained by chemoselective ligation between a ionic-complementary self-assembling peptide (called EAK) and three different bioactive molecules: an adhesive sequence with 4 Glycine-Arginine-Glycine-Aspartic Acid-Serine-Proline (GRGDSP) motifs per chain, an adhesive peptide mapped on h-Vitronectin and the growth factor Insulin-like Growth Factor-1 (IGF-1). The mesenchymal stem cell adhesion assays showed a significant increase in adhesion and proliferation for the hydrogels decorated with each of the synthesized conjugates; moreover, such functionalized 3D hydrogels support cell spreading and elongation, validating the use of this class of self-assembly peptides-based material as very promising 3D model scaffolds for cell cultures, at variance of the less realistic 2D ones. Furthermore, small amplitude oscillatory shear tests showed that the presence of IGF-1-conjugate did not alter significantly the viscoelastic properties of the hydrogels even though differences were observed in the nanoscale structure of the scaffolds obtained by changing their composition, ranging from long, well-defined fibers for conjugates with adhesion sequences to the compact and dense film for the IGF-1-conjugate
Daily Rhythmicity of Behavior of Nine Species of South American Feral Felids in Captivity
The authors analyzed the daily activity rhythms of the domestic cat and of eight of the ten feral felid species that are indigenous to South America. All species showed daily rhythmicity of activity in captivity under a natural light-dark cycle. The robustness of the rhythmicity varied from species to species, but the grand mean of 34% was within the range of robustness previously described for mammalian species ranging in size from mice to cattle. There was not a sharp division between diurnal and nocturnal felids. Instead, what was found was a gradient of diurnality going from the predominantly nocturnal margay (72% of activity counts during the night) to the predominantly diurnal jaguarundi (87% of activity counts during the day) with the remaining species lying in between these two extremes. The ecological implications of temporal niche variations are discussed
Relationship between circulating E-selectin, DD genotype of angiotensin-converting-enzyme, and cardiovascular damage in central obese subjects
Fifty-six young central obese patients were investigated to evaluate relationships between soluble E-selectin (sE-S), angiotensin-converting enzyme (ACE) gene polymorphism, left ventricular function and structure, and carotid morphology by determination of sE-S and ACE genotypes. Our results indicated that central obese subjects with concomitant higher levels of sE-S and ACE DD genotype may be characterized by early cardiovascular alterations and then considered a particular subset of subjects at higher risk of cardiovascular disease
The Role of Plasma Cells as a Marker of Chronic Endometritis: A Systematic Review and Meta-Analysis
Chronic endometritis (CE) is the persistent inflammation of the endometrial lining associated with infertility and various forms of reproductive failures. The diagnosis of CE is based on the histological evidence of stromal plasma cells; however, standardized methods to assess plasma cells are still lacking. In the present paper, we aimed to determine the most appropriate plasma cell threshold to diagnose CE based on pregnancy outcomes. Three electronic databases were searched from their inception to February 2022 for all studies comparing pregnancy outcomes between patients with CE and patients without CE. The relative risk (RR) of pregnancy, miscarriage, and/or live birth rates were calculated and pooled based on the plasma cell threshold adopted. A p-value < 0.05 was considered significant. Nine studies adopting different thresholds (1 to 50 plasma cells/10 HPF) were included. In the meta-analysis, we only found a significant association between miscarriage rate and a plasma cell count & GE; 5/10 HPF (RR = 2.4; p = 0.007). Among studies not suitable for meta-analysis, CE showed an association with worsened pregnancy only when high thresholds (10 and 50/10 HPF) were adopted. In conclusion, our study suggests that the presence of plasma cells at low levels (<5/10 HPF) may not predict worsened pregnancy outcomes. Based on these findings, a threshold of & GE;5 plasma cells/10 HPF may be more appropriate to diagnose CE
Short- and long-term effects of a cardiac rehabilitation program in patients implanted with a left ventricular assist device
The efficacy of cardiac rehabilitation in heart-failure patients who received a left-ventricular assist device (LVAD) instead of heart transplantation (HTx) is still unclear. This study aims to evaluate whether cardiac rehabilitation is beneficial in LVAD as HTx patients in the short term and whether its effects in LVAD patients persist over time. Twenty-five LVAD patients were evaluated by functional and psychological tests at admission (T0) and discharge (T1) of a 4-week inpatient structured rehabilitation program, and follow-ups 3 (T2), 6 (T3), and 12 months (T4) after discharge. Twenty-five matched HTx patients were also studied from T0 to T1 to compare the improvements in the six-minute walk test (6MWT). The quality-of-life scores substantially improved in LVAD patients and the 6MWT showed the same functional recovery as in HTx patients from T0 to T1. After T1, numerous LVAD patients withdrew from the study. However, the 6MWT outcome increased further from T1 to T3, with a positive trend during the follow-ups. Hemoglobin and the ventilatory performance increased, and the psychological perception of heart-failure symptoms and pain further improved at T2. In conclusion, exercise-based rehabilitation programs provide similar beneficial effects in LVAD and HTx patients, without deterioration in LVAD patients up to 12 months after discharge
Transcatheter Ablation for Atrial Fibrillation in Patients with Hypertrophic Cardiomyopathy: Long-term Results and Clinical Outcomes
- …