3,766 research outputs found
Supernova neutrino detection in Borexino
In this paper, the performances of Borexino as a Supernova neutrino detector are analyzed and discussed. The expected neutrino signal from a typical Type II Supernova at a distance of 10 kpc is calculated: a burst of around 240
events would appear in Borexino within a time interval of about 10 s. Most of these events would come from the reaction channels ¯νe + p → e+ + n and ν + p → ν + p, while about 30 events would be induced by the interaction of the Supernova neutrino flux on 12C in the liquid scintillator: for most of these reactions, Borexino features unique detection capabilities, thanks to its low-energy sensitivity, ultra-low radioactive background and large homogeneous volume. The possibility to tag and identify the different neutrino detection reactions gives access to key information concerning Supernova physics and non-standard neutrino properties. The detection of neutrinos via elastic scattering off protons in Borexino is discussed here for the
first time: this reaction is proven to be a powerful component of the neutrino-induced burst of events. Finally, a viable “Supernova trigger” condition is established, which
allows to detect a Supernova explosion up to a distance of 63 kpc
Effect of strain in the proximal ligand on the binding of nitric oxide and carbon monoxide to chelated protoheme complexes
The binding of NO and CO to chelated protoheme-L-histidine methyl ester (HM-H), protoheme-glycyl-L-histidine methyl ester (HM-GH), and free protoheme (HM) has been studied in methanol-DMSO solution. In all cases, the NO adducts are five-coordinated indicating that binding of NO occurs with displacement of the axial base and confirms the strong negative trans effect exerted by NO in heme complexes, though it is found that the presence of strain in the iron-histidine bond of HM-H has a positive influence on NO binding, making it thermodynamically more favorable than for HM-GH. The equilibrium constants thus decrease in the series HM>HM-H>HM-GH. In contrast to NO, CO has a positive trans effect, and therefore, an opposite trend is observed in the binding of this ligand to the heme complexe
Analysis of the Secondary Structure of the Catalytic Domain of Mouse Ras Exchange Factor CDC25Mm
The minimal active domain GEF domain. of the mouse Ras exchange factor CDC25Mm was purified to homogeneity
from recombinant Escherichia coli culture. The 256 amino acids polypeptide shows high activity in vitro and forms a stable
complex with H-ras p21 in absence of guanine nucleotides. Circular dichroism CD. spectra in the far UV region indicate
that this domain is highly structured with a high content of a-helix 42%.. Near UV CD spectra evidenced good signal due
to phenylalanine and tyrosine while a poor contribution was elicited by the three tryptophan residues contained in this
domain. The tryptophan fluorescence signal was scarcely affected by denaturation of the protein or by formation of the
binary complex with H-ras p21, suggesting that the Trp residues, which are well conserved in the GEF domain of several
Ras-exchange factors, were exposed to the surface of the protein and they are not most probably directly involved in the
interaction with Ras proteins. q1998 Elsevier Science B.
The Power of Odor Persuasion: The Incorporation of Olfactory Cues in Virtual Environments for Personalized Relaxation
Olfaction is the most ancient sense and is directly connected with emotional areas in the brain. It gives rise to perception linked to emotion both in everyday life and in memory-recall activities. Despite its emotional primacy in perception and its role in sampling the real physical world, olfaction is rarely used in clinical psychological settings because it relies on stimuli that are difficult to deliver. However, recent developments in virtual-reality tools are creating novel possibilities for the engagement of the sense of smell in this field. In this article, we present the relevant features of olfaction for relaxation purposes and then discuss possible future applications of involving olfaction in virtual-reality interventions for relaxation. We also discuss clinical applications, the potential of new tools, and current obstacles and limitations
The situational version of the brief COPE: Dimensionality and relationships with goal-related variables
This study is aimed at investigating the dimensionality of the situational version of the Brief COPE, a questionnaire that is frequently used to assess a broad range of coping responses to specific difficulties, by comparing five different factor models highlighted in previous studies. It also aimed at exploring the relationships among coping responses, personal goal commitment and progress. The study involved 606 adults (male = 289) ranging in age from 19 to 71. Using confirmatory factor analysis, we compared five models and assessed relationships of coping responses with goal commitment and progress. The results confirmed the theoretical factor structure of the situational Brief COPE. All the 14 dimensions showed acceptable reliability and relationships with goal commitment and progress, attesting the reliability and usefulness of this measure to evaluate coping responses to specific events
Vertigo and dizziness in children: An update
Background: Vertigo and dizziness are relatively infrequent in paediatric patients, but specific data on the prevalence of these disorders are limited and influenced by various factors, including the age of the examined population. These conditions often have a significant impact on patients’ and parents’ quality of life. The aim of this paper is to investigate the prevalence of different aetiologies of vertigo in the paediatric population through a systematic review. Methods: According to PRISMA guidelines, a systematic review of the literature was performed. Medline and Embase were searched from January 2011 through to 10 September 2021. The search yielded 1094 manuscripts, which were reduced to 7 upon the application of inclusion criteria. Results: A total of 2470 paediatric patients were evaluated by the selected papers. Vestibular Migraine was the most frequently diagnosed condition, occurring alone or in association with other diseases. Overall, audio-vestibular disorders represented the second cause of vertigo, and the prevalence appears to increase according to age growth. Over the years, even though we assisted in the amelioration of diagnostic rates, partially related to an improvement in diagnostic tools, the aetiology of vertigo remains still unclear in a variable percentage of patients. Conclusion: Vertigo in children, despite being an uncommon symptom, requires a multidisciplinary approach, often involving Paediatricians, Neurologists and Otorhinolaryngologists. A comprehensive evaluation of children suffering from vertigo is crucial for establishing a successful therapy and reducing parental worries
New Measurement of the Relative Scintillation Efficiency of Xenon Nuclear Recoils Below 10 keV
Liquid xenon is an important detection medium in direct dark matter
experiments, which search for low-energy nuclear recoils produced by the
elastic scattering of WIMPs with quarks. The two existing measurements of the
relative scintillation efficiency of nuclear recoils below 20 keV lead to
inconsistent extrapolations at lower energies. This results in a different
energy scale and thus sensitivity reach of liquid xenon dark matter detectors.
We report a new measurement of the relative scintillation efficiency below 10
keV performed with a liquid xenon scintillation detector, optimized for maximum
light collection. Greater than 95% of the interior surface of this detector was
instrumented with photomultiplier tubes, giving a scintillation yield of 19.6
photoelectrons/keV electron equivalent for 122 keV gamma rays. We find that the
relative scintillation efficiency for nuclear recoils of 5 keV is 0.14, staying
constant around this value up to 10 keV. For higher energy recoils we measure a
value around 20%, consistent with previously reported data. In light of this
new measurement, the XENON10 experiment's results on spin-independent
WIMP-nucleon cross section, which were calculated assuming a constant 0.19
relative scintillation efficiency, change from cm to
cm for WIMPs of mass 100 GeV/c, and from
cm to cm for WIMPs of mass 30
GeV/c.Comment: 8 pages, 8 figure
Physical therapy for benign positional vertigo of posterior canal: the role of alternated Epley and Semont maneuvers.
Objective: To investigate if alternated Epley (EP) and Semont (ST) maneuvers could be more effective than repetition of the
same in benign paroxysmal positional vertigo of posterior semicircular canal (pBPPV). Design: We retrospectively reviewed the
outcome of pBPPV patients treated with a second maneuver for the persistence of positional nystagmus. Study Sample:
Forty-seven patients underwent 2 STs, 64 with 2 EPs, and 71 EPs followed by ST. Videonystagmography and Dizziness Handicap
Inventory (DHI) questionnaire were performed. Results: Absence of positional nystagmus was achieved after 2 maneuvers in 136
patients with pBPPV: 65.9% in the ST group, 70.3% in the EP group, and 84.5% in the EP-ST group. Alternated EP and ST were
significantly more effective than repeated ST (P = .03), while we found no significant difference when compared with repeated EP
(P = .07). At 1-month follow-up, 12 patients showed persistent positional nystagmus without difference between groups. After 1
month, the 46 patients with negative outcome had significantly higher DHI values (P = .01) than other 136 patients with pBPPV.
Conclusions: Alternated EP and ST seemed more effective than repeating the same maneuver in treating pBPPV, and this should
be confirmed in prospective clinical studies. Resolution of nystagmus after maneuvers was fundamental to reduce handicap
deriving from dizziness as reported in DHI
Importance of Sexual Function Assessment in Multidimensional Evaluation of AGHD Patients: Results from the MAGHD Study.
Background: Adult growth hormone deficiency (AGHD) is a debilitating clinical condition leading to decreased quality of life (QoL). The impact of reduced muscle mass, weakening and loss of vitality on QoL have been well characterized in AGHD. The impact of AGHD on sexual function, a recognized factor able to modify well-being, has never been investigated. Aim: To investigate the prevalence of sexual dysfunction in AGHD patients referring to a single endocrinological center and grouped according to their his- tory of r-hGH therapy.Methods: The Management of Adult Growth Hormone Deficiency (MAGHD) Study is a pro- spective, real-life trial aiming to improve management of AGHD patients through a smartphone app (MAGHD App)and a wearable device. The 83 AGHD enrolled patients (31 Females, 52 Males, mean age 56.27 + 14.68 years) were divided in 3 groups (G) according to r-hGH therapy: on long-term r-hGH therapy (G1, n=32), previously treated with r-hGH (G2, n=20), never treated (G3, n=31). Within the first phase of the study, a large database was created collecting clinical, biochemical and psychological data. In addition to QLS-H and QoL-AGHDA routinely used to as- sess QoL, IIEF-15 and FSFI were employed to evaluate sexual function in males and females, respectively. The nonparametric Kruskal-Wallis test was used for compar- ison among 3 groups.Results: Here only baseline data of the MAGHD Study are presented.According to IIEF-15 results, the prevalence of erectile dysfunction (ED) in male AGHD cohort was 60%. Erectile function (EF) score was signifi- cantly higher in G1 compared to both G2 and G3 (p < 0.05) with an ED prevalence of 35% in G1, 75% in G2 and 75% in G3. Even excluding patients with serum testosterone lower than 2 ng/ml and older than 65 years, ED prevalence did not change significantly in the 3 groups. Moreover, EF do- main was inversely and directly correlated to age (R20.130, β-0.360) and IGF1 levels (R20.156, β0.395), respectively. The prevalence of female sexual dysfunction according to FSFI was 89.3%. Even though desire, arousal, lubrication and overall scores were significantly higher (better results) in G1 compared to G2 and G3 (p < 0.05), no correlation resulted between FSFI domains and IGF1 levels. Instead an inverse correlation resulted between desire domain and age.Conclusions: This study, performed in a real-life clinical setting, demonstrates a high prevalence of sexual dysfunc- tion in AGHD patients and that r-hGH treatment seems to be associated to better sexual outcomes. These results suggest that the evaluation of sexual function should be in- tegrated in the global assessment of AGHD patients since sexual activity is a fundamental domain able to influence both well-being and QoL
Trunk fat increase is prevented both in patients undergoing long- lasting continuous r-hGH therapy and in those who discontinued r-hGH compared to untreated patients: results from baseline data of the MAGHD study
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