7,123 research outputs found
Mid-infrared wavelength- and frequency-modulation spectroscopy with a pump-modulated singly-resonant optical parametric oscillator
We describe the implementation of the wavelength- and frequency-modulation spectroscopy techniques using a singly-resonant optical parametric oscillator (OPO) pumped by a fiber-amplified diode laser. Frequency modulation of the diode laser was transferred to the OPO¿s mid-infrared idler output, avoiding the need for external modulation devices. This approach thus provides a means of implementing these important techniques with powerful, widely tunable, mid-infrared sources while retaining the simple, flexible modulation properties of diode lasers
Mid-IR continuous-wave fiber-laser-pumped optical parametric oscillators
We review recent developments in continuous-wave mid-infrared optical parametric oscillators pumped by fiber lasers. Such devices are potentially valuable spectroscopic sources providing high output powers and rapid, wide-range tuning in the mid-infrared molecular fingerprint region
The trypanosome alternative oxidase:a potential drug target?
New drugs against Trypanosoma brucei, the causative agent of Human African Trypanosomiasis, are urgently needed to replace the highly toxic and largely ineffective therapies currently used. The trypanosome alternative oxidase (TAO) is an essential and unique mitochondrial protein in these parasites and is absent from mammalian mitochondria, making it an attractive drug target. The structure and function of the protein are now well characterized, with several inhibitors reported in the literature which show potential as clinical drug candidates. In this review we provide an update on the functional activity and structural aspects of TAO. We then discuss TAO inhibitors reported to date, problems encountered with in vivo testing of these compounds, and discuss the future of TAO as a therapeutic target.PostprintPeer reviewe
On a conjecture about Dirac's delta representation using q-exponentials
A new representation of Dirac's delta-distribution, based on the so-called
q-exponentials, has been recently conjectured. We prove here that this
conjecture is indeed valid
Five-Year Cost of Dementia: Medicare
About 5.5 million older adults are living with dementia, a chronic, progressive disease characterized by severe cognitive decline. This number will likely grow significantly as the U.S. population ages, which has cost implications for the Medicare program. A full accounting of these additional expenses will help policymakers plan for them in their Medicare budgets. In this study, Norma Coe and colleagues examined survival and Medicare expenditures in older adults with and without dementia to estimate dementia’s incremental costs to Medicare in the five years after diagnosis
A Double-Mode RR Lyrae Star with a Strong Fundamental Mode Component
NSVS 5222076, a thirteenth magnitude star in the Northern Sky Variability
Survey, was identified by Oaster as a possible new double-mode RR Lyrae star.
We confirm the double-mode nature of NSVS 5222076, supplementing the survey
data with new V band photometry. NSVS 5222076 has a fundamental mode period of
0.4940 day and a first overtone period of 0.3668 day. Its fundamental mode
light curve has an amplitude twice as large as that of the first overtone mode,
a ratio very rarely seen. Data from the literature are used to discuss the
location in the Petersen diagram of double-mode RR Lyrae stars having strong
fundamental mode pulsation. Such stars tend to occur toward the short period
end of the Petersen diagram, and NSVS 5222976 is no exception to this rule.Comment: 14 pages, 4 figures, To be published in the March, 2006, issue of
PAS
- …