Search results for "iTED"
showing 10 items of 2408 documents
Increase in transmitted resistance to non-nucleoside reverse transcriptase inhibitors among newly diagnosed HIV-1 infections in Europe
2014
Background: One out of ten newly diagnosed patients in Europe was infected with a virus carrying a drug resistant mutation. We analysed the patterns over time for transmitted drug resistance mutations (TDRM) using data from the European Spread program.Methods: Clinical, epidemiological and virological data from 4317 patients newly diagnosed with HIV-1 infection between 2002 and 2007 were analysed. Patients were enrolled using a pre-defined sampling strategy.Results: The overall prevalence of TDRM in this period was 8.9% (95% CI: 8.1-9.8). Interestingly, significant changes over time in TDRM caused by the different drug classes were found. Whereas nucleoside resistance mutations remained con…
Special Issue on Higher education and its clients : institutional responses to changes in demand and in environment
2002
02048
The most 100 cited papers in addiction research on cannabis, heroin, cocaine and psychostimulants. A bibliometric cross-sectional analysis
2021
The number of citations a peer-reviewed article receives is often used as a measure of its importance and scientific impact. This paper identifies, describes and categorizes the highly cited papers in addiction research on cannabis, heroin, cocaine and psychostimulants. Highly cited papers were identified in the Web of Science Core Collection database. Several bibliometric indicators were calculated. Social network analysis was applied to draw groups of authors and institutions with the greatest number of collaborations and co-words. The number of citations for the top 100 cited articles ranged from 649 to 4,672. The articles were published in 40 journals. The subject category Substance Abu…
Market entry decisions of US small and medium-sized software firms
2008
Purpose: This paper investigates market entry decisions of the U.S. software SMEs by analyzing the impact of the most obvious factors (cultural distance, geographical distance, country risk, and three market size variables) in traditional internationalization theories to target country selection. By investigating the influence of these commonly cited macro-level factors, this study proposes the best indicator for market entry decisions of the U.S. small and mediumsized software firms. Design/methodology/approach: This study uses quantitative research approach applied on a sample of 100 U.S. small and medium-sized software firms. Findings: Empirical findings in this study indicate that verti…
Conversion rate determinants in e-commerce websites. What about moderation effects?
2018
Online retailers invest significant resource to improve conversion rates, defined as the proportion of website visitors that make a purchase. Using 1,184 observations from six e-commerce websites, this paper aims to analyse conversion rate determinants, also considering moderation effects of seasonality and webpage speed of load. Results show that free shipping and discounts policy have a positive effect on the conversion rate, moderated by seasonality and load speed. These finding could be useful guidelines for e-commerce managers in order to allocate their limited resources to the most relevant factor to increase online sales.
Orientations and Capabilities of Born Global Firms from Emerging Markets
2018
Purpose The purpose of this paper is to examine the impact of entrepreneurial orientation and networking capabilities of born global firms in an emerging market on marketing strategy and foreign market performance. Design/methodology/approach Structural equation modeling was used to analyze data from 1,001 internationalized firms in an emerging market and to test seven hypotheses regarding the development of marketing strategy and foreign market performance. Findings Marketing strategy was found to mediate the relationship between entrepreneurial orientation and networking capability and foreign market performance, while foreign market performance is affected by entrepreneurial orientation…
Wide range excitation of visible luminescence in nanosilica
2010
The visible luminescence of nanometer-sized silica particles (7 nm mean diameter) was investigated using time resolved spectroscopy. This luminescence is characterized by a wide excitation in the visible and ultraviolet range. The emission spectrum is centred at 2.72 eV with a full width at half maximum of 0.70 eV when excited above 3.5 eV, whereas it progressively empties on the high energy side when excited below 3.5 eV. Moreover, the lifetime falls in the ns timescale and decreases on increasing the emission energy. These features are due to the exceptionally broad inhomogeneous distribution of the emitting centres peculiar to the silica nanoparticles. © 2010 Elsevier B.V. All rights res…
How important is roaming in the photodegradation of nitrobenzene?
2020
At low excitation energies nitrobenzene photoreleases NO with low translational and rotational energy, while at higher excitation energies NO is photoreleased with both low and high translational and rotational energy. The fast products are formed through a singlet-triplet crossing (STC) region featuring an oxaziridine ring, while a ground state roaming mechanism was suggested to produce the slow molecules. Computing translational and rotational energies performing CASSCF classical dynamics, we here prove how the same oxaziridine STC can account for both fast and slow photoproducts, depending on the region of the seam through which the ground state is populated. A roaming-type STC/CI has al…
Tailoring the Emission of Fluorinated Bipyridine-Chelated Iridium Complexes
2018
New functionalized tris(2′,6′-difluoro-2,3′-bipyridinato-N,C4′)iridium(III) ((dfpypy)3Irs) complexes, including small molecules and their dendrimer embedded analogoues, were synthesized and characterized. It is demonstrated that both the fac-(dfpypy)3Ir-based polyphenylene dendrimers and (triisopropylsilyl)ethynyl (TIPSE)-substituted (dfpypy)3Ir complexes induce large bathochromic shifts (∼50 nm) of emission bands compared with fac-(dfpypy)3Ir. This is due to the pronounced 3π–π* character of emissive excited states and the extended conjugation. A further remarkable feature is the small bathochromic shift of the emissions of fac-tris(2-phenylpyridine)iridium (fac-(ppy)3Ir)-based polyphenyle…
Regiochemical memory in the adiabatic photolysis of thymine-derived oxetanes. A combined ultrafast spectroscopic and CASSCF/CASPT2 computational stud…
2020
[EN] The photoinduced cycloreversion of oxetanes has been thoroughly investigated in connection with the photorepair of the well-known DNA (6-4) photoproducts. In the present work, the direct photolysis of the two regioisomers arising from the irradiation of benzophenone (BP) and 1,3-dimethylthymine (DMT), namely the head-to-head (HH-1) and head-to-tail (HT-1) oxetane adducts, has been investigated by combining ultrafast spectroscopy and theoretical multiconfigurational quantum chemistry analysis. Both the experimental and computational results agree with the involvement of an excited triplet exciplex(3)[BPMIDLINE HORIZONTAL ELLIPSISDMT]* for the photoinduced oxetane cleavage to generate(3)…