1,638 research outputs found
Social interactions or business transactions? What customer reviews disclose about Airbnb marketplace
Airbnb is one of the most successful examples of sharing economy marketplaces. With rapid and global market penetration, understanding its attractiveness and evolving growth opportunities is key to plan business decision making. There is an ongoing debate, for example, about whether Airbnb is a hospitality service that fosters social exchanges between hosts and guests, as the sharing economy manifesto originally stated, or whether it is (or is evolving into being) a purely business transaction platform, the way hotels have traditionally operated. To answer these questions, we propose a novel market analysis approach that exploits customersâ reviews. Key to the approach is a method that combines thematic analysis and machine learning to inductively develop a custom dictionary for guestsâ reviews. Based on this dictionary, we then use quantitative linguistic analysis on a corpus of 3.2 million reviews collected in 6 different cities, and illustrate how to answer a variety of market research questions, at fine levels of temporal, thematic, user and spatial granularity, such as (i) how the business vs social dichotomy is evolving over the years, (ii) what exact words within such top-level categories are evolving, (iii) whether such trends vary across different user segments and (iv) in different neighbourhoods
^{63}Cu, ^{35}Cl, and ^{1}H NMR in the S=1/2 Kagom\'e Lattice ZnCu_{3}(OH)_{6}Cl_{2}
ZnCu(OH)Cl () is a promising new candidate for an
ideal Kagom\'e Heisenberg antiferromagnet, because there is no magnetic phase
transition down to 50 mK. We investigated its local magnetic and lattice
environments with NMR techniques. We demonstrate that the intrinsic local spin
susceptibility {\it decreases} toward T=0, but that slow freezing of the
lattice near 50 K, presumably associated with OH bonds, contributes to a
large increase of local spin susceptibility and its distribution. Spin dynamics
near T=0 obey a power-law behavior in high magnetic fields.Comment: Phys. Rev. Lett. (in press
Spectral, optical and transport properties of the adiabatic anisotropic Holstein model: Application to slightly doped organic semiconductors
Spectral, optical and transport properties of an anisotropic
three-dimensional Holstein model are studied within the adiabatic
approximation. The parameter regime is appropriate for organic semiconductors
used in single crystal based field effect transistors. Different approaches
have been used to solve the model: self-consistent Born approximation valid for
weak electron-phonon coupling, coherent potential approximation exact for
infinite dimensions, and numerical diagonalization for finite lattices. With
increasing temperature, the width of the spectral functions gets larger and
larger making the approximation of quasi-particle less accurate. On the
contrary, their peak positions are never strongly renormalized in comparison
with the bare ones. As expected, the density of states is characterized by an
exponential tail corresponding to localized states at low temperature. For weak
electron-lattice coupling, the optical conductivity follows a Drude behavior,
while, for intermediate electron-lattice coupling, a temperature dependent peak
is present at low frequency. For high temperatures and low particle densities,
the mobility always exhibits a power-law behavior as function of temperature.
With decreasing the particle density, at low temperature, the mobility shows a
transition from metallic to insulating behavior. Results are discussed in
connection with available experimental data.Comment: 9 pages, 7 figures, submitted to Phys. Rev.
Dynamic Scaling in the Susceptibility of the Spin-1\2 Kagome Lattice Antiferromagnet Herbertsmithite
The spin-1/2 kagome lattice antiferromagnet herbertsmithite,
ZnCu(OH)Cl, is a candidate material for a quantum spin liquid
ground state. We show that the magnetic response of this material displays an
unusual scaling relation in both the bulk ac susceptibility and the low energy
dynamic susceptibility as measured by inelastic neutron scattering. The
quantity with can be expressed as a
universal function of or . This scaling is discussed in
relation to similar behavior seen in systems influenced by disorder or by the
proximity to a quantum critical point.Comment: 5 pages, 3 figures v2: updated to match published version
Antimicrobial Activity of the Iron-Chelator, DIBI, against Multidrug-Resistant Canine Methicillin-Susceptible Staphylococcus pseudintermedius: A Preliminary Study of Four Clinical Strains
Staphylococcus pseudintermedius is an important opportunistic pathogen causing various
infections in dogs. Furthermore, it is an emerging zoonotic agent and both multidrug-resistant
methicillin-resistant S. pseudintermedius (MRSP) as well as methicillin-susceptible (MSSP) strains
represent an important therapeutic challenge to veterinary medicine and pose a potential threat to
human health. We tested representative S. pseudintermedius clinical strains from dogs suffering from
otitis externa for their susceptibilities to a panel of 17 antimicrobials compared to DIBI. DIBI, unlike
antibiotics, is a novel water-soluble hydroxypyridinone-containing iron-chelating agent that deprives
microbes of growth-essential iron and has been previously shown to inhibit methicillin-resistant
Staphylococcus aureus (MRSA). We also characterised the strains according to whether they harbour
key antibiotic resistance genes. The strains each displayed multiple antimicrobial resistance patterns;
all were negative for the mecA gene and possessed the tetK and tetM genes, but they varied as to
their possession of the ermB gene. However, all the isolates had similar susceptibility to DIBI with
low MICs (2 ”g/mL or 0.2 ”M). Because the four MSSPs were equally susceptible to DIBI, subject
to confirmation with additional strains, this could provide a potential non-antibiotic, anti-infective
alternative approach for the treatment of antimicrobial-resistant canine S. pseudintermedius otitis
Improved fertilization and implantation rates after non-touch zona pellucida microdrilling of mouse oocytes with a 1.48 ÎŒm diode laser beam
The safety of microdrilling the zona pellucida of moose oocytes with a 1.48 ÎŒm diode laser has been investigated by determining the ability of mouse oocytes to fertilize in vitro and develop in vivo. Mice born after transfer of control and zona pelludda-microdrilled embryos into foster mothers were submitted to anatomical and immunohisto-chemical investigations, and their aptitude to breed was assessed in two subsequent generations. Decolonization of the oocytes with hyaluronidase induced a reduction of the fertilization and implantation rates, which was attributed to a zona hardening phenomenon. After laser zona pellucida microdrilling, these rates were restored to those obtained with embryos derived from untreated oocyte-cumulus complexes. Pups derived from zona pellucida microdrilled embryos were comparable with those obtained from control embryos, confirming the lack of deleterious effects of the laser treatment In conclusion, the 1.48 ÎŒm diode laser allows safe microdrilling of the zona pellucida of mouse oocytes after decoronization with hyaluronidase. Based on the health of the F2 generation and the lack of neuroanatom-ical and neurochemical differences, we concluded that this technology may be investigated in the human, particularly when the zona pellucida represents the main impediment for fertilization or embryo hatchin
Spin Dynamics of the Spin-1/2 Kagome Lattice Antiferromagnet ZnCu_3(OH)_6Cl_2
We have performed thermodynamic and neutron scattering measurements on the
S=1/2 kagome lattice antiferromagnet Zn Cu_3 (OH)_6 Cl_2. The susceptibility
indicates a Curie-Weiss temperature of ~ -300 K; however, no magnetic order is
observed down to 50 mK. Inelastic neutron scattering reveals a spectrum of low
energy spin excitations with no observable gap down to 0.1 meV. The specific
heat at low-T follows a power law with exponent less than or equal to 1. These
results suggest that an unusual spin-liquid state with essentially gapless
excitations is realized in this kagome lattice system.Comment: 4 pages, 3 figures; v2: Updates to authors list and references; v3:
Updated version; v4: Published versio
Data on before and after the traceability system of veterinary antimicrobial prescriptions in small animals at the university veterinary teaching hospital of Naples
Over recent decades, antimicrobial resistance has been considered one of the most relevant issues of public health. The aim of our study was to evaluate the differences related to the prescription of antimicrobials at the University Veterinary Teaching Hospital, before and after the mandatory use of veterinary electronic prescription (VEP). In particular, the consumption of antimicrobials was examined, especially taking into consideration the recommendations of prudent use. A comparison of data collected before and after the use of electronic prescription highlighted that during the period chosen for the study, the choice of antimicrobial molecules was appropriate, favoring those of âfirstâ and âsecond line.â However, prescription and the use of some molecules not registered for veterinary medicine were observed in the period before VEP. Broad-spectrum antimicrobials, including penicillins with ÎČ-lactamase inhibitors, as well as first-generation cephalosporins and fluoroquinolones, were the most frequently prescribed compounds. There are few studies conducted in Italy aimed at investigating the use of antimicrobials in companion animals under field conditions and with particular regard to prudent use recommendations. This type of study underlines the importance of electronic medical recording in veterinary practice and, above all, its usefulness in monitoring the use of certain antimicrobial agents classified as of critical importance in human medicine
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