background and aims: the world health organization and united nations children’s fund (unicef) recommended executive breastfeeding for 6 months after birth. the purpose of this study was to determine the prevalence of executive breastfeeding in iran by a meta-analysis study to be used by policy-makers in order to health programmer plan in this field. methods: in this meta-analysis study, the da...

The mechanism or mechanisms that cause intrapulmonary arteriovenous anastomoses (IPAVA) to either open during exercise in subjects breathing room air and at rest when breathing hypoxic gas mixtures, or to close during exercise while breathing 100% oxygen, remain unknown. During conditions when IPAVA are open, plasma epinephrine (EPI) and dopamine (DA) concentrations both increase, potentially r...

A one-year series of hourly average PM10 observations, which was obtained from the urban and national park air monitoring station at Taipei (Taiwan), was analyzed by descriptive statistics and fractal methods to examine the temporal structures of PM10 concentrations. It was found that all PM10 measurements exhibited the characteristic right-skewed unimodal frequency distribution and long-term m...

We describe the investigation of an outbreak of Q fever in the town of Cheltenham, England. The outbreak was detected in June 2007, and prospective and retrospective case finding identified 30 confirmed or probable human cases. The investigation identified windborne spread of Coxiella burnetii from nearby sheep farms as the most likely source of infection. A telephone survey was conducted to id...

Room temperature lasing from optically pumped single defects in a two-dimensional (2-D) photonic bandgap (PBG) crystal is demonstrated. The high-Q optical microcavities are formed by etching a triangular array of air holes into a halfwavelength thick multiquantum-well waveguide. Defects in the 2-D photonic crystal are used to support highly localized optical modes with volumes ranging from 2 to...

Patients with clinically stable asthma may show ventilation-perfusion (V'A/Q') mismatch. Nitric oxide (NO), a potent endogenous vasodilator, is increased in exhaled air of asthmatics. Such an increased NO production may be detrimental for optimal V'A/Q' balance owing to the potential inhibition of hypoxic pulmonary vasoconstriction. This study was undertaken to investigate the relationship betw...

PURPOSE To measure the anterior corneal asphericity (Q) with different corneal diameters. SETTING Department of Physics (Optometry), University of Minho, Braga, Portugal. METHODS Thirty-six eyes of 36 patients were evaluated using a videokeratoscope, and the Q-values were recorded. Topographic data were also analyzed using Vol-CT 6.89 software (Sarver & Associates, Inc) to obtain the Q-valu...

To the Editor: Recent outbreaks of Q fever in the Netherlands and the United Kingdom raised public awareness about this ubiquitous bacterial disease known for decades to circulate worldwide (1–4). The disease, which ranges from a self-recovering infl uenza-like illness to pneumonia and severe meningoencephalitis, myocarditis, or endocarditis, is usually transmitted from animals to humans by air...

If I say the word “wave” in no particular context, the image that most probably springs to your mind is one of a roughly periodic undulation on the surface of a pond or, perhaps, the sea. But the concept of a wave in classical physics is actually much more general, and in particular the periodicity is not really an essential aspect. (Huygens, Fourier...) At least in classical (i.e., pre-relativ...