1,495 research outputs found
Robustness of the transition against compositional and structural ageing in S/F/S heterostructures
We have studied the temperature induced thermodynamic transition in
Nb/PdNi/Nb Superconductor/Ferromagnetic/Superconductor (SFS) heterostructures
by microwave measurements of the superfluid density. We have observed a shift
in the transition temperature with the ageing of the heterostructures,
suggesting that structural and/or chemical changes took place. Motivated by the
electrodynamics findings, we have extensively studied the local structural
properties of the samples by means of X-ray Absorption Spectroscopy (XAS)
technique, and the compositional profile by Time-of-Flight Secondary Ion Mass
Spectrometry (ToF-SIMS). We found that the samples have indeed changed their
properties, in particular for what concerns the interfaces and the composition
of the ferromagnetic alloy layer. The structural and compositional data are
consistent with the shift of the transition toward the behaviour of
heterostructures with different F layers. An important emerging indication to
the physics of SFS is the weak relevance of the ideality of the interfaces:
even in aged samples, with less-than-ideal interfaces, the temperature-induced
transition is still detectable albeit at a different critical F
thickness.Comment: 11 pages, 9 figures, accepted for publication on Phys. Rev. B,
http://journals.aps.org/prb
Total Degree Formula for the Generic Offset to a Parametric Surface
We provide a resultant-based formula for the total degree w.r.t. the spatial
variables of the generic offset to a parametric surface. The parametrization of
the surface is not assumed to be proper.Comment: Preprint of an article to be published at the International Journal
of Algebra and Computation, World Scientific Publishing,
DOI:10.1142/S021819671100680
Growth performance in heavy lambs experimentally treated with 17 β-estradiol
European and Italian legislation have banned use
of growth promoters in livestock since 1988, but epidemiological
data show that anabolic drugs are still being used
illegally. Recent surveys carried out on the cattle farms in
Northern Italy have confirmed the presence of growthpromoting
hormones. Authors report data on growth performances
in 80 Valle del Belice×Comisana weaned lambs
experimentally treated with 17 beta-estradiol with 0.5 ml
solution of oil Depot Estradiol ® (containing 5 mg of 17β-
estradiol valerate) by intramuscular injection into the thigh.
The experiment was founded by the National Ministry of
Health, to validate histological test for surveillance and
control of growth-promoting hormones in sheep. This study
confirmed the strong correlation between clinical and anatomopathological
features and growth performances of treated
animals. Otherwise, no significant differences were found on in vivo performance of the lambs. Estradiol treatment
showed heavier shoulders and necks on treated lambs,
while the loins were significantly lighter. Moreover, lambestradiol-
treated groups showed lower separable and inseparable
fat percentage than lamb-control groups
Efficacy of eprinomectin pour-on against Dictyocaulus arnfieldi infection in donkeys (Equus asinus).
A trial to assess the efficacy of eprinomectin (EPM) against the lungworm Dictyocaulus arnfieldi was carried out on 15, naturally-infected donkeys. Ten animals were treated with a 'pour-on' EPM preparation (at a dose of 0.5mg/kg bodyweight), and five animals acted as controls. EPM was 100% effective in eliminating faecal larvae from day 7, until the end of study at day 28. No adverse drug-reactions or side-effects were observed in any of the treated donkeys
Plasma disposition, concentration in the hair, and anthelmintic efficacy of eprinomectin after topical administration in donkeys
Objective-To investigate plasma disposition, concentration in the hair, and anthelmintic efficacy of eprinomectin after topical administration in donkeys. Animals-12 donkeys naturally infected with strongyle nematodes. Procedures-The pour-on formulation of eprinomectin approved for use in cattle was administered topically to donkeys at a dosage of 0.5 mg/kg. Heparinized blood samples and hair samples were collected at various times between 1 hour and 40 days after administration. Samples were analyzed via high-performance liquid chromatography with fluorescence detection. Fecal strongyle egg counts were performed by use of a modified McMaster technique before and at weekly intervals for 8 weeks after treatment. Results-Plasma concentration and systemic availability of eprinomectin were relatively higher in donkeys, compared with values reported for other animal species. Concerning the anthelmintic efficacy against strongyle nematodes, eprinomectin was completely effective (100%) on days 7 and 14 and highly effective (> 99%) until the end of the study at 56 days after treatment. No abnormal clinical signs or adverse reactions were observed for any donkeys after treatment. Conclusions and Clinical Relevance-Eprinomectin had excellent safety. The relatively high plasma concentration after topical administration could result in use of eprinomectin for the control and treatment of parasitic diseases in donkeys
Dual targeting of HER3 and MEK may overcome HER3-dependent drug-resistance of colon cancers
Although the medical treatment of colorectal cancer has evolved greatly in the last years, a significant portion of early-stage patients develops recurrence after therapies. The current clinical trials are directed to evaluate new drug combinations and treatment schedules. By the use of patient-derived or established colon cancer cell lines, we found that the tyrosine kinase receptor HER3 is involved in the mechanisms of resistance to therapies. In agreement, the immunohistochemical analysis of total and phospho-HER3 expression in 185 colorectal cancer specimens revealed a significant correlation with lower disease-free survival. Targeting HER3 by the use of the monoclonal antibody patritumab we found induction of growth arrest in all cell lines. Despite the high efficiency of patritumab in abrogating the HER3-dependent activation of PI3K pathway, the HER2 and EGFR-dependent MAPK pathway is activated as a compensatory mechanism. Interestingly, we found that the MEK-inhibitor trametinib inhibits, as expected, the MAPK pathway but induces the HER3-dependent activation of PI3K pathway. The combined treatment results in the abrogation of both PI3K and MAPK pathways and in a significant reduction of cell proliferation and survival. These data suggest a new strategy of therapy for HER3-overexpressing colon cancers
Kinematical coincidence method in transfer reactions
A new method to extract high resolution angular distributions from
kinematical coincidence measurements in binary reactions is presented.
Kinematic is used to extract the center of mass angular distribution from the
measured energy spectrum of light particles. Results obtained in the case of
10Be+p-->9Be+d reaction measured with the CHIMERA detector are shown. An
angular resolution of few degrees in the center of mass is obtained.Comment: 6 Page 10 Figures submitted to Nuclear Instruments and Methods
Recommended from our members
Effect of diet composition and weight loss on resting energy expenditure in the POUNDS LOST study
Weight loss reduces energy expenditure, but it is unclear whether dietary macronutrient composition affects this reduction. We hypothesized that energy expenditure might be modulated by macronutrient composition of the diet. The POUNDS LOST study, a prospective, randomized controlled trial in 811 overweight/obese people who were randomized in a 2×2 design to diets containing 20en% or 40en% fat and 15en% or 25en% (diets with 65%, 55%, 45% and 35% carbohydrate) provided the data to test this hypothesis. Resting energy expenditure (REE) was measured at baseline, 6 and 24 months using a ventilated hood. REE declined at 6 months by 99.5±8.0 kcal/d in men and 55.2±10.6 kcal/d in women during the first 6 months. This decline was related to the weight loss, and there was no difference between the diets. REE had returned to baseline by 24 months, but body weight was still 60% below baseline. Measured REE at 6 months was significantly lower than the predicted (−18.2±6.7 kcal/d) and was the result of significant reductions from baseline in the low fat diets (65% or 55% carbohydrate), but not in the high fat diet groups. By 24 months the difference had reversed with measured REE being slightly but significantly higher than predicted (21.8±10.1 kcal/d). In conclusion, we found that REE fell significantly after weight loss but was not related to diet composition. Adaptive thermogenesis was evident at 6 months, but not at 24 months
Absence of system xc⁻ on immune cells invading the central nervous system alleviates experimental autoimmune encephalitis
Background: Multiple sclerosis (MS) is an autoimmune demyelinating disease that affects the central nervous system (CNS), leading to neurodegeneration and chronic disability. Accumulating evidence points to a key role for neuroinflammation, oxidative stress, and excitotoxicity in this degenerative process. System x(c)- or the cystine/glutamate antiporter could tie these pathological mechanisms together: its activity is enhanced by reactive oxygen species and inflammatory stimuli, and its enhancement might lead to the release of toxic amounts of glutamate, thereby triggering excitotoxicity and neurodegeneration.
Methods: Semi-quantitative Western blotting served to study protein expression of xCT, the specific subunit of system x(c)-, as well as of regulators of xCT transcription, in the normal appearing white matter (NAWM) of MS patients and in the CNS and spleen of mice exposed to experimental autoimmune encephalomyelitis (EAE), an accepted mouse model of MS. We next compared the clinical course of the EAE disease, the extent of demyelination, the infiltration of immune cells and microglial activation in xCT-knockout (xCT(-/-)) mice and irradiated mice reconstituted in xCT(-/-) bone marrow (BM), to their proper wild type (xCT(+/+)) controls.
Results: xCT protein expression levels were upregulated in the NAWM of MS patients and in the brain, spinal cord, and spleen of EAE mice. The pathways involved in this upregulation in NAWM of MS patients remain unresolved. Compared to xCT(+/+) mice, xCT(-/-) mice were equally susceptible to EAE, whereas mice transplanted with xCT(-/-) BM, and as such only exhibiting loss of xCT in their immune cells, were less susceptible to EAE. In none of the above-described conditions, demyelination, microglial activation, or infiltration of immune cells were affected.
Conclusions: Our findings demonstrate enhancement of xCT protein expression in MS pathology and suggest that system x(c)- on immune cells invading the CNS participates to EAE. Since a total loss of system x(c)- had no net beneficial effects, these results have important implications for targeting system x(c)- for treatment of MS
- …
