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Broad-scale latitudinal patterns of genetic diversity among native European and introduced house sparrow (Passer domesticus) populations.

Introduced species offer unique opportunities to study evolution in new environments, and some provide opportunities for understanding the mechanisms underlying macroecological patterns. We sought to determine how introduction history impacted genetic diversity and differentiation of the house sparrow (Passer domesticus), one of the most broadly distributed bird species. We screened eight microsat

Teachers' Voice Use in Teaching Environments: A Field Study Using Ambulatory Phonation Monitor.

This case-control designed field study examines the vocal behavior in teachers with self-estimated voice problems (VP) and their age- and school-matched voice healthy (VH) colleagues. It was hypothesized that teachers with and teachers without VP use their voices differently regarding fundamental frequency, sound pressure level (SPL), and in relation to the background noise.

A summary of the 25th International Papillomavirus Conference 2009: Vaccines, screening, epidemiology and therapeutics

The 25th International Papillomavirus Conference was held in Malmo, Sweden, on May 8-14, 2009. The conference encompassed all areas of papillomavirus (PV) research, from clinical vaccinology to molecular biology. This review highlights some of the 237 presentations and 887 abstracts which were presented and summarizes sessions on prophylactic vaccines, screening, epidemiology and therapeutics. Imp

Molecular and genetic diversity in the metastatic process of melanoma.

Diversity between metastatic melanoma tumours in individual patients is known; however, the molecular and genetic differences remain unclear. To examine the molecular and genetic differences between metastatic tumours, we performed gene-expression profiling of 63 melanoma tumours obtained from 28 patients (two or three tumours/patient), followed by analysis of their mutational landscape, using tar

Intergenerational transmission of young motherhood. Evidence from Sweden, 1986-2009

This study examines the intergenerational transmission of fertility patterns from mothers who had their first birth at young ages to their daughters using nationally representative longitudinal data from from population registers in Sweden, 1986-2009. It tests several mechanisms, including education, labor market attachment, socio-economic background, and family characteristics, that may intervene

Band-Edge Diagrams of Core-Shell Semiconductor Dots

We have calculated band-edge diagrams for spherical core shell nanocrystal quantum dots for all combinations of AlN, GaN, and InN, as well as all combinations of AlP, GaP, AlAs, GaAs, InP, In As, AlSb, GaSb, and LnSb, as a function of core radius, with the outer radius of the shell held fixed. We have calculated the Gamma- and the X-conduction band minima, the valence band maximum, and the effecti

Chiral Surface Plasmon Polaritons on Metallic Nanowires

Chiral surface plasmon polaritons (SPPs) can be generated by linearly polarized light incident at the end of a nanowire, exciting a coherent superposition of three specific nanowire waveguide modes. Images of chiral SPPs on individual nanowires obtained from quantum dot fluorescence excited by the SPP evanescent field reveal the chirality predicted in our theoretical model. The handedness and spat

Phase Measurement of a Fano Resonance Using Tunable Attosecond Pulses

We study photoionization of argon atoms close to the 3s(2)3p(6) -> 3s(1)3p(6)4p Fano resonance using an attosecond pulse train and a weak infrared probe field. An interferometric technique combined with tunable attosecond pulses allows us to determine the phase of the photoionization amplitude as a function of photon energy. We interpret the experimental results using an analytical two-photon mode

Photoprotection in a purple phototrophic bacterium mediated by oxygen-dependent alteration of carotenoid excited-state properties

Carotenoids are known to offer protection against the potentially damaging combination of light and oxygen encountered by purple phototrophic bacteria, but the efficiency of such protection depends on the type of carotenoid. Rhodobacter sphaeroides synthesizes spheroidene as the main carotenoid under anaerobic conditions whereas, in the presence of oxygen, the enzyme spheroidene monooxygenase cata

General Approach to the Evolution of Singlet Nanoparticles from a Rapidly Quenched Point Source

Among the numerous point vapor sources, microsecond-pulsed spark ablation at atmospheric pressure is a versatile and environmentally friendly method for producing ultrapure inorganic nanoparticles ranging from singlets having sizes smaller than 1 nm to larger agglomerated structures. Due to its fast quenching and extremely high supersaturation, coagulational growth already begins at the atomic sca

Direct Impact of Nonequilibrium Aggregates on the Structure and Morphology of Pdadmac/SDS Layers at the Air/Water Interface

We discuss different nonequilibrium mechanisms by which bulk aggregates directly modify, and can even control, the interfacial structure and morphology of an oppositely charged polyelectrolyte/surfactant (P/S) mixture. Samples are categorized at the air/water interface with respect to the dynamic changes in the bulk phase behavior, the bulk composition, and the sample history using complementary s

Evaluation of user hand and body impact on multiple antenna handset

From our experimental investigation of multiple-antenna performance and user impact of a realistic mobile terminal setup, we find that apart from the important loss of efficiency due to the user hand, the impact on the individual antennna elements and the directional impact of the user body shadowing have quite small influence on the diversity and capacity performance. It is found that the top and

Decline of C-peptide during the first year after diagnosis of Type 1 diabetes in children and adolescents

Aims/hypothesis: We studied the decline of C-peptide during the first year after diagnosis of Type 1 diabetes (T1D), and its relation to various factors. Methods: 3824/4017 newly diagnosed patients (95%) were classified as T1D in a national study. In a non-selected subgroup of 1669 T1D patients we determined non-fasting C-peptide both at diagnosis and after 1 year, and analyzed decline in relation

A porous silicon immunoassay platform for fluorometric determination of alpha-synuclein in human cerebrospinal fluid

Levels of total and/or oligomeric alpha-synuclein may be used as a biomarker tool to aid in the diagnosis and development of new disease-modifying therapies. We report here on a porous silicon antibody microarray for the fluorimetric determination of cerebrospinal fluid levels of total alpha-synuclein, a protein involved the pathology of Parkinson's disease. The surface of porous silicon has a 3-d