5,418 research outputs found
Performance Analysis of a Prototype High-Concentration Photovoltaic System Coupled to Silica Optical Fibers
High-concentration photovoltaic (HCPV) systems are one of the most promising technologies for the generation of renewable energy with high-conversion efficiency. Their development is still at an early stage, but the possibility of integrating high-concentration systems into buildings offers new opportunities to achieve the net-zero-energy building goal. Herein, the optical and energetic performance of a hybrid daylightingâHCPV prototype based on pure- or doped-silica optical fibers (OFs) to guide 2000Ă concentrated sunlight inside the buildings is evaluated. There, the light can either be used to illuminate interior spaces or projected on solar cells to generate electricity. The system equipped with a single 400 ÎŒm core-diameter OF is demonstrated to achieve a total efficiency of 15% and an optical efficiency of 45%
Prokaryotic Diversity of the Composting Thermophilic Phase: The Case of Ground Coffee Compost
Waste biomass coming from a local coffee company, which supplied burnt ground coffee
after an incorrect roasting process, was employed as a starting material in the composting
plant of the Experimental Station of the University of Naples Federico II at Castel Volturno (CE).
The direct molecular characterization of compost using 13C-NMR spectra, which was acquired
through cross-polarization magic-angle spinning, showed a hydrophobicity index of 2.7% and an
alkyl/hydroxyalkyl index of 0.7%. Compost samples that were collected during the early âactive
thermophilic phaseâ (when the composting temperature was 63 C) were analyzed for the prokaryotic
community composition and activities. Two complementary approaches, i.e., genomic and
predictive metabolic analysis of the 16S rRNA V3âV4 amplicon and culture-dependent analysis,
were combined to identify the main microbial factors that characterized the composting process. The
whole microbial community was dominated by Firmicutes. The predictive analysis of the metabolic
functionality of the community highlighted the potential degradation of peptidoglycan and the ability
of metal chelation, with both functions being extremely useful for the revitalization and fertilization
of agricultural soils. Finally, three biotechnologically relevant Firmicutes members, i.e., Geobacillus
thermodenitrificans subsp. calidus, Aeribacillus pallidus, and Ureibacillus terrenus (strains CAF1, CAF2,
and CAF5, respectively) were isolated from the âactive thermophilic phaseâ of the coffee composting.
All strains were thermophiles growing at the optimal temperature of 60 C. Our findings contribute
to the current knowledge on thermophilic composting microbiology and valorize burnt ground coffee
as waste material with biotechnological potentialities
PRENATAL DEVELOPMENT OF TEMPORO-MANDIBULAR JOINTS: STATE OF ART
The aim of this work is to analyze the state of the art of temporo-mandibular joint (MJ) to understand the varoius stage of the development of the same during embryogenesis. Various theories have been analyzed, such as the formation of apoptotic or the important role of growth factors, or the Valencia et studies in which are analyzed to numerous articular diseases in various stage of development. By the aforementioned studies show that many factors, of a different nature, are to be involved in the prenatal developlment of this important joint
A brief anatomo-surgical dissection guide to human neck: results of the collaboration between the university of Palermo and the university of Malta
The aim of this article is to show methods for dissection of the neck. In the summer of 2017 a group of students of the University of Palermo that have already passed the exam of Human Anatomy took a 4 weeks dissection course at the University of Malta. The students were provided with a dissection kit, video recording equipment and cameras for taking pictures. They dissected the skin, the subcutaneous tissue, the muscular bundles, the muscles, the vascular and nervous bundles, the nerves, the larynx, the trachea and the esophagus. This paper presents the results of the dissection course and a small and simple guide to young students and medical doctors who want to learn the bases of neck dissection
A Study of Time-Dependent CP-Violating Asymmetries and Flavor Oscillations in Neutral B Decays at the Upsilon(4S)
We present a measurement of time-dependent CP-violating asymmetries in
neutral B meson decays collected with the BABAR detector at the PEP-II
asymmetric-energy B Factory at the Stanford Linear Accelerator Center. The data
sample consists of 29.7 recorded at the
resonance and 3.9 off-resonance. One of the neutral B mesons,
which are produced in pairs at the , is fully reconstructed in
the CP decay modes , , , () and , or in flavor-eigenstate
modes involving and (). The flavor of the other neutral B meson is tagged at the time of
its decay, mainly with the charge of identified leptons and kaons. The proper
time elapsed between the decays is determined by measuring the distance between
the decay vertices. A maximum-likelihood fit to this flavor eigenstate sample
finds . The value of the asymmetry amplitude is determined from
a simultaneous maximum-likelihood fit to the time-difference distribution of
the flavor-eigenstate sample and about 642 tagged decays in the
CP-eigenstate modes. We find , demonstrating that CP violation exists in the neutral B meson
system. (abridged)Comment: 58 pages, 35 figures, submitted to Physical Review
Measurement of ISR-FSR interference in the processes e+ e- --> mu+ mu- gamma and e+ e- --> pi+ pi- gamma
Charge asymmetry in processes e+ e- --> mu+ mu- gamma and e+ e- --> pi+ pi-
gamma is measured using 232 fb-1 of data collected with the BABAR detector at
center-of-mass energies near 10.58 GeV. An observable is introduced and shown
to be very robust against detector asymmetries while keeping a large
sensitivity to the physical charge asymmetry that results from the interference
between initial and final state radiation. The asymmetry is determined as
afunction of the invariant mass of the final-state tracks from production
threshold to a few GeV/c2. It is compared to the expectation from QED for e+ e-
--> mu+ mu- gamma and from theoretical models for e+ e- --> pi+ pi- gamma. A
clear interference pattern is observed in e+ e- --> pi+ pi- gamma, particularly
in the vicinity of the f_2(1270) resonance. The inferred rate of lowest order
FSR production is consistent with the QED expectation for e+ e- --> mu+ mu-
gamma, and is negligibly small for e+ e- --> pi+ pi- gamma.Comment: 32 pages,29 figures, to be submitted to Phys. Rev.
Measurement of the quasi-elastic axial vector mass in neutrino-oxygen interactions
The weak nucleon axial-vector form factor for quasi-elastic interactions is
determined using neutrino interaction data from the K2K Scintillating Fiber
detector in the neutrino beam at KEK. More than 12,000 events are analyzed, of
which half are charged-current quasi-elastic interactions nu-mu n to mu- p
occurring primarily in oxygen nuclei. We use a relativistic Fermi gas model for
oxygen and assume the form factor is approximately a dipole with one parameter,
the axial vector mass M_A, and fit to the shape of the distribution of the
square of the momentum transfer from the nucleon to the nucleus. Our best fit
result for M_A = 1.20 \pm 0.12 GeV. Furthermore, this analysis includes updated
vector form factors from recent electron scattering experiments and a
discussion of the effects of the nucleon momentum on the shape of the fitted
distributions.Comment: 14 pages, 10 figures, 6 table
Measurement of the Branching Fraction for B- --> D0 K*-
We present a measurement of the branching fraction for the decay B- --> D0
K*- using a sample of approximately 86 million BBbar pairs collected by the
BaBar detector from e+e- collisions near the Y(4S) resonance. The D0 is
detected through its decays to K- pi+, K- pi+ pi0 and K- pi+ pi- pi+, and the
K*- through its decay to K0S pi-. We measure the branching fraction to be
B.F.(B- --> D0 K*-)= (6.3 +/- 0.7(stat.) +/- 0.5(syst.)) x 10^{-4}.Comment: 7 pages, 1 postscript figure, submitted to Phys. Rev. D (Rapid
Communications
Search for the W-exchange decays B0 --> Ds(*)- Ds(*)+
We report a search for the decays , , in a sample of 232
million decays to \BBb ~pairs collected with the \babar detector
at the PEP-II asymmetric-energy storage ring. We find no significant
signal and set upper bounds for the branching fractions: and at 90% confidence level.Comment: 8 pages, 2 figures, submitted to PRD-R
Measurement of the B+ --> p pbar K+ Branching Fraction and Study of the Decay Dynamics
With a sample of 232x10^6 Upsilon(4S) --> BBbar events collected with the
BaBar detector, we study the decay B+ --> p pbar K+ excluding charmonium decays
to ppbar. We measure a branching fraction Br(B+ --> p pbar
K+)=(6.7+/-0.5+/-0.4)x10^{-6}. An enhancement at low ppbar mass is observed and
the Dalitz plot asymmetry suggests dominance of the penguin amplitude in this B
decay. We search for a pentaquark candidate Theta*++ decaying into pK+ in the
mass range 1.43 to 2.00 GeV/c2 and set limits on Br(B+ -->
Theta*++pbar)xBr(Theta*++ --> pK+) at the 10^{-7} level.Comment: 8 pages, 7 postscript figures, submitted to Phys. Rev. D (Rapid
Communications
- âŠ