4,137 research outputs found
Universal contact for a Tonks-Girardeau gas at finite temperature
We determine the finite-temperature momentum distribution of a strongly
interacting 1D Bose gas in the Tonks-Girardeau (impenetrable-boson) limit under
harmonic confinement, and explore its universal properties associated to the
scale invariance of the model. We show that, at difference from the unitary
Fermi gas in three dimensions, the weight of its large-momentum tails -- given
by the Tan's contact -- increase with temperature, and calculate the
high-temperature universal second contact coefficient using a virial expansion.Comment: 6 pages, 2 figure
Fermionization of a strongly interacting Bose-Fermi mixture in a one-dimensional harmonic trap
We consider a strongly interacting one-dimensional (1D) Bose-Fermi mixture
confined in a harmonic trap. It consists of a Tonks-Girardeau (TG) gas (1D Bose
gas with repulsive hard-core interactions) and of a non-interacting Fermi gas
(1D spin-aligned Fermi gas), both species interacting through hard-core
repulsive interactions. Using a generalized Bose-Fermi mapping, we determine
the exact particle density profiles, momentum distributions and behaviour of
the mixture under 1D expansion when opening the trap. In real space, bosons and
fermions do not display any phase separation: the respective density profiles
extend over the same region and they both present a number of peaks equal to
the total number of particles in the trap. In momentum space the bosonic
component has the typical narrow TG profile, while the fermionic component
shows a broad distribution with fermionic oscillations at small momenta. Due to
the large boson-fermion repulsive interactions, both the bosonic and the
fermionic momentum distributions decay as at large momenta, like in
the case of a pure bosonic TG gas. The coefficient is related to the
two-body density matrix and to the bosonic concentration in the mixture. When
opening the trap, both momentum distributions "fermionize" under expansion and
turn into that of a Fermi gas with a particle number equal to the total number
of particles in the mixture.Comment: revised version; 8 pages, 7 figure
Impact of pneumococcal conjugate vaccination: a retrospective study of hospitalization for pneumonia in North-East Italy
Introduction. Pneumonia remains a common reason for hospitalizing
infants and the elderly worldwide, and streptococcal infection
is often responsible. The aim of this study was to assess the
burden of pneumonia in a large general population.
Methods. All pneumonia-related hospitalizations from 2004 to
2013 in north-east Italy were identified from the hospital records
with a first-listed diagnosis on discharge of bacterial pneumonia,
or a first-listed diagnosis on discharge of meningitis, septicemia
or empyema associated with a secondary diagnosis of bacterial
pneumonia. We identified major comorbidities, calculated agespecific
case-fatality rates (CFR), and estimated the related cost
to the health care system.
Results. Of the 125,722 hospitalizations identified, 96.9% were
cases of pneumonia, 2.4% of septicemia, 0.4% of meningitis, and
0.3% of empyema; 75.3% of hospitalizations involved 65 65-yearolds.
The overall CFR was 12.4%, and it increased with age,
peaking in people over 80 (19.6%).
The mean annual pneumonia-associated hospitalization rate was
204.6 per 100,000 population, and it peaked in 0- to 4-year-old children
(325.6 per 100,000 in males, 288.9 per 100,000 in females),
and adults over 65 (844.9 per 100,000 in males, 605.7 per 100,000
in females).
Hospitalization rates dropped over the years for the 0-4 year-olds,
and rose for people over 80. The estimated overall annual cost of
these pneumonia-related hospitalizations was approximately \u20ac 41
million.
Conclusions. This study shows that the burden on resources for
pneumonia-related hospitalization is an important public health
issue. Prevention remains the most valuable tool for containing pneumonia,
and vaccination strategies can help in the primary prevention
of infection, possibly reducing the number of cases in all age groups
Bodily ownership modulation in defensive responses: Physiological evidence in brain-damaged patients with pathological embodiment of other's body parts
Do conscious beliefs about the body affect defensive mechanisms within the body? To answer this question we took advantage from a monothematic delusion of bodily ownership, in which brain-damaged patients misidentify alien limbs as their own. We investigated whether the delusional belief that an alien hand is their own hand modulates a subcortical defensive response, such as the hand-blink reflex. The blink, dramatically increases when the threated hand is inside the defensive peripersonal-space of the face. In our between-subjects design, including patients and controls, the threat was brought near the face either by the own hand or by another person’s hand. Our results show an ownership-dependent modulation of the defensive response. In controls, as well as in the patients’ intact-side, the response enhancement is significantly greater when the threat was brought near the face by the own than by the alien hand. Crucially, in the patients’ affected-side (where the pathological embodiment occurs), the alien (embodied) hand elicited a response enhancement comparable to that found when the threat is brought near the face by the real hand. These findings suggest the existence of a mutual interaction between our conscious beliefs about the body and the physiological mechanisms within the body
Oral contraceptives combined with interferon β in multiple sclerosis
Objective: To test the effect of oral contraceptives (OCs) in combination with interferon b (IFN-b)
on disease activity in patients with relapsing-remitting multiple sclerosis (RRMS).
Methods: One hundred fifty women with RRMS were randomized in a 1:1:1 ratio to receive IFNb-1a
subcutaneously (SC) only (group 1), IFN-b-1a SC plus ethinylstradiol 20 mg and desogestrel
150 mg (group 2), or IFN-b-1a SC plus ethinylestradiol 40 mg and desogestrel 125 mg (group 3).
The primary endpoint was the cumulative number of combined unique active (CUA) lesions on
brain MRI at week 96. Secondary endpoints included MRI and clinical and safety measures.
Results: The estimated number of cumulative CUA lesions at week 96 was 0.98 (95% confidence
interval [CI] 0.81–1.14) in group 1, 0.84 (95% CI 0.66–1.02) in group 2, and 0.72 (95% CI
0.53–0.91) in group 3, with a decrease of 14.1% (p 5 0.24) and 26.5% (p 5 0.04) when comparing
group 1 with groups 2 and 3, respectively. The number of patients with no gadoliniumenhancing
lesions was greater in group 3 than in group 1 (p 5 0.03). No significant differences
were detected in other secondary endpoints. IFN-b or OC discontinuations were equally distributed
across groups.
Conclusions: Our results translate the observations derived from experimental models to patients,
supporting the anti-inflammatory effects of OCs with high-dose estrogens, and suggest possible
directions for future research
Quest for wine yeasts—An old story revisited
Numerous studies have described the yeast biota of grapes, and grape must in order to understand better the succession of yeasts during fermentation of wine. The origin of the wine yeasts has been rather controversial. By using more elaborate isolation methods, classical genetic analysis and electrophoretic karyotyping of monosporic clones, with this study, credible proof now exists that the vineyard is the primary source for the wine yeasts and that strains found on the grapes can be followed through the fermentation process
Identification of domains in apoA-I susceptible to proteolysis by mast cell chymase. Implications for HDL function.
When stimulated, rat serosal mast cells degranulate and secrete a cytoplasmic neutral protease, chymase. We studied the fragmentation of apolipoprotein (apo) A-I during proteolysis of HDL(3) by chymase, and examined how chymase-dependent proteolysis interfered with the binding of eight murine monoclonal antibodies (Mabs) against functional domains of apoA-I. Size exclusion chromatography of HDL(3) revealed that proteolysis for up to 24 h did not alter the integrity of the alpha-migrating HDL, whereas a minor peak containing particles of smaller size with prebeta mobility disappeared after as little as 15 min of incubation. At the same time, generation of a large (26 kDa) polypeptide containing the N-terminus of apoA-I was detected. This large fragment and other medium-sized fragments of apoA-I produced after prolonged treatment with chymase were found to be associated with the alphaHDL; meanwhile, small lipid-free peptides were rapidly produced. Incubation of HDL(3) with chymase inhibited binding of Mab A-I-9 (specific for prebeta(1)HDL) most rapidly (within 15 min) of the eight studied Mabs. This rapid loss of binding was paralleled by a similar reduction in the ability of HDL(3) to induce high-affinity efflux of cholesterol from macrophage foam cells, indicating that proteolysis had destroyed an epitope that is critical for this function. In sharp contrast, prolonged degradation of HDL(3) by chymase failed to reduce the ability of HDL(3) to activate LCAT, even though it led to modification of three epitopes in the central region of apoA-I that are involved in lecithin cholesterol acyltransferase (LCAT) activation. This differential sensitivity of the two key functions of HDL(3) to the proteolytic action of mast cell chymase is compatible with the notion that, in reverse cholesterol transport, intactness of apoA-I is essential for prebeta(1)HDL to promote the high-affinity efflux of cellular cholesterol, but not for the alpha-migrating HDL particles to activate LCAT
Energy Embodiment in Brazilian Agriculture: An Overview of 23 Crops
The amount of energy required to produce a commodity or to supply a service varies from one production system to another and consequently giving rise to differing levels of environmental efficiency. Moreover, since energy prices have been continuously increasing over time, this energy amount may be a factor that has economic worth. Biomass production has a variety of end-products such as food, energy, and fiber; thus, taking into account the similarity in end-product of different crops (e.g.: sunflower, peanuts, or soybean for oil) it is possible to evaluate which crops require less energy per functional unit, such as starch, oil, and protein. This information can be used in decision-making about policies for food safety or bioenergy. In this study, 23 crops were evaluated allowing for a comparison in terms of energy embodied per functional unit. Crops were grouped as follows: starch, oil, horticultural, perennial and fiber, to provide for a deeper analysis of alternatives for the groups, and subsidize further studies comparing conventional and alternative production systems such as organic or genetically modified organisms, in terms of energy. The best energy balance observed was whole sugarcane (juice, bagasse and straw) with a surplus of 268 GJ ha−1 yr−1; palm shows the highest energy return on investment with a ratio of approximately 30:1. For carbohydrates and protein production, cassava and soybean, respectively, emerged as the crops offering the greatest energy savings in the production of these functional foods
Identification of subgroups of early breast cancer patients at high risk of nonadherence to adjuvant hormone therapy: results of an italian survey.
The aim of this study was the identification of subgroups of patients at higher risk of nonadherence to adjuvant
hormone therapy for breast cancer. Using recursive partitioning and amalgamation (RECPAM) analysis, the
highest risk was observed in the group of unmarried, employed women, or housewives. This result might be
functional in designing tailored intervention studies aimed at improvement of adherence.
Background: Adherence to adjuvant endocrine therapy (HT) is suboptimal among breast cancer patients. A high rate
of nonadherence might explain differences in survival between clinical trial and clinical practice. Tailored interventions
aimed at improving adherence can only be implemented if subgroups of patients at higher risk of poor adherence are
identified. Because no data are available for Italy, we undertook a large survey on adherence among women taking
adjuvant HT for breast cancer. Patients and Methods: Patients were recruited from 10 cancer clinics in central Italy.
All patients taking HT for at least 1 year were invited, during one of their follow-up visit, to fill a confidential questionnaire.
The association of sociodemographic and clinical characteristics of participants with adherence was
assessed using logistic regression. The RECPAM method was used to evaluate interactions among variables and to
identify subgroups of patients at different risk of nonadherence. Results: A total of 939 patients joined the study and
18.6% of them were classified as nonadherers. Among possible predictors, only age, working status, and switching
from tamoxifen to an aromatase inhibitor were predictive of nonadherence in multivariate analysis. RECPAM analysis
led to the identification of 4 classes of patients with a different likelihood of nonadherence to therapy, the lowest being
observed in retired women with a low level of education, the highest in the group of unmarried, employed women, or
housewives. Conclusion: The identification of these subgroups of “real life” patients with a high prevalence of
nonadherers might be functional in designing intervention studies aimed at improving adherenc
Plexin-B1 Activates NF-κB and IL-8 to Promote a Pro-Angiogenic Response in Endothelial Cells
The semaphorins and their receptors, the plexins, are proteins related to c-Met and the scatter factors that have been implicated in an expanding signal transduction network involving co-receptors, RhoA and Ras activation and deactivation, and phosphorylation events. Our previous work has demonstrated that Semaphorin 4D (Sema4D) acts through its receptor, Plexin-B1, on endothelial cells to promote angiogenesis in a RhoA and Akt-dependent manner. Since NF-\u3baB has been linked to promotion of angiogenesis and can be activated by Akt in some contexts, we wanted to examine NF-\u3baB in Sema4D treated cells to determine if there was biological significance for the pro-angiogenic phenotype observed in endothelium.
METHODS/PRINCIPAL FINDINGS:
Using RNA interference techniques, gel shifts and NF-\u3baB reporter assays, we demonstrated NF-\u3baB translocation to the nucleus in Sema4D treated endothelial cells occurring downstream of Plexin-B1. This response was necessary for endothelial cell migration and capillary tube formation and protected endothelial cells against apoptosis as well, but had no effect on cell proliferation. We dissected Plexin-B1 signaling with chimeric receptor constructs and discovered that the ability to activate NF-\u3baB was dependent upon Plexin-B1 acting through Rho and Akt, but did not involve its role as a Ras inhibitor. Indeed, inhibition of Rho by C3 toxin and Akt by LY294002 blocked Sema4D-mediated endothelial cell migration and tubulogenesis. We also observed that Sema4D treatment of endothelial cells induced production of the NF-\u3baB downstream target IL-8, a response necessary for angiogenesis. Finally, we could show through co-immunofluorescence for p65 and CD31 that Sema4D produced by tumor xenografts in nude mice activated NF-\u3baB in vessels of the tumor stroma.
CONCLUSION/SIGNIFICANCE:
These findings provide evidence that Sema4D/Plexin-B1-mediated NF-\u3baB activation and IL-8 production is critical in the generation a pro-angiogenic phenotype in endothelial cells and suggests a new therapeutic target for the anti-angiogenic treatment of some cancer
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