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The majority of studies on phonation types have focused on low vowels due to the minimal effects of their first formant on harmonic amplitude. In studies of multiple vowel qualities, reports on the relationship between vowel and voice quality are mixed: some show similar formant frequencies across phonation types (e.g. Abramson, Nye & Luangthongkum 2007, Khan 2012), while others show different formant frequencies depending on voice quality (e.g. Ren 1992, Kuang 2011). Results differ as to whether the degree of non-modal phonation varies (Andruski & Ratliff 2000, Kuang 2011) or does not vary (Esposito 2012, Khan 2012) across different vowel qualities. The present study draws on innovations which allow for more accurate corrections for the effects of formant frequencies on spectral measures (i.e. Hanson 1995, Iseli, Shue & Alwan 2007) to examine the relationship between vowel quality and voice quality, in eight languages – !Xóõ, Burmese, Gujarati, Jalapa de Díaz Mazatec, Mon, Santa Ana del Valle Zapotec, White Hmong, and Yi. While no significant difference in the degree of non-modal phonation due to vowel quality was found, results showed a crosslinguistic pattern in the relationship between vowel quality and voice quality: vowels with higher log(F1) and log(F2) values tended to be produced with creakier phonation, while vowels with lower log(F1) and log(F2) values tended to be produced with breathier phonation, but only on the measure H1*-H2*.
Although many children adopted internationally show remarkable recovery once placed in families, as a group they continue to exhibit persisting developmental deficits and delays in self-regulation. The current study uses a stratified, randomized, controlled trial to evaluate the effects of mindfulness-based and executive function trainings (EFTs) on internationally adopted (IA) children's self-regulation, including effortful/inhibitory control, attention, delay of gratification, and emotion-regulation. IA children ages 6–10 years were randomized into mindfulness training (MT), EFT, or no intervention (NI) groups. The MT and EFT groups attended 12 one-hour group sessions. Ninety-six children (MT, n = 33; EFT, n = 32; NI, n = 31) completed the study and were tested on computerized and non-computerized measures of self-regulation. Compared with the NI group, the MT group improved delay of gratification, and the EFT group improved inhibitory control and selective attention. There was no effect of either intervention on emotion regulation. MTs and EFTs show promise for improving self-regulation in IA children.
Antimicrobial stewardship programs are effective in optimizing antimicrobial prescribing patterns and decreasing the negative outcomes of antimicrobial exposure, including the emergence of multidrug-resistant organisms. In dialysis facilities, 30%–35% of antimicrobials are either not indicated or the type of antimicrobial is not optimal. Although antimicrobial stewardship programs are now implemented nationwide in hospital settings, programs specific to the maintenance dialysis facilities have not been developed.
To quantify the effect of an antimicrobial stewardship program in reducing antimicrobial prescribing.
Study design and setting
An interrupted time-series study in 6 outpatient hemodialysis facilities was conducted in which mean monthly antimicrobial doses per 100 patient months during the 12 months prior to the program were compared to those in the 12-month intervention period.
Implementation of the antimicrobial stewardship program was associated with a 6% monthly reduction in antimicrobial doses per 100 patient months during the intervention period (P=.02). The initial mean of 22.6 antimicrobial doses per 100 patient months decreased to a mean of 10.5 antimicrobial doses per 100 patient months at the end of the intervention. There were no significant changes in antimicrobial use by type, including vancomycin. Antimicrobial adjustments were recommended for 30 of 145 antimicrobial courses (20.6%) for which there were sufficient clinical data. The most frequent reasons for adjustment included de-escalation from vancomycin to cefazolin for methicillin-susceptible Staphylococcus aureus infections and discontinuation of antimicrobials when criteria for presumed infection were not met.
Within 6 hemodialysis facilities, implementation of an antimicrobial stewardship was associated with a decline in antimicrobial prescribing with no negative effects.
One of the most enduring symbols of space exploration is a planet surrounded by a ring. This symbol inspires a celestial context: nothing on Earth is like it. It has been a wonderful surprise that the ringed planets are just as beautiful and scientifically compelling seen close up. Furthermore, the ringed planets are not just objects of beauty, but complicated physical systems that provide a local laboratory and analogy for other cosmic systems like galaxies and planet-forming disks. For a general review, see Esposito (2014). For more details, see the individual chapters that follow in this book.
We now know that planetary rings, once thought unique to the planet Saturn, exist around all the giant planets. These rings are not solid objects, but are composed of countless particles with sizes from specks of dust to small moons. For each planet, the rings are quite different. Jupiter's ring is thin and composed of dust-like small particles. Saturn's rings are broad, bright, and opaque. Uranus has narrow, dark rings among broad lanes of dust that are invisible from Earth. Neptune's rings include incomplete arcs restricted to a small range of their circumference. All rings lie predominantly within their planet's Roche limit, where tidal forces would destroy a self-gravitating fluid body. They are also within the planet's magnetosphere and, in the case of Uranus, they are within the upper reaches of the planetary atmosphere.
The common occurrence of ring material around the outer planets is one of the major scientific findings of the past 40 years. The new ring systems were discovered by both spacecraft and ground-based observers, often surprising us by contradicting our expectations. The rings’ appearance and composition differ among the various planets, and likewise within each ring system. The broadest set of rings and the most identified processes are found around the planet Saturn, which has been scrutinized by the US/European Cassini space mission since 2004.
We present the results of a search for strong single radio pulses emitted by magnetars and for FRB signals in the fields of magnetars observed at the Parkes radio telescope within the NAPA project P626. Unsurprisingly, given the short total observing time, no extragalacic FRB signal was found up to a DM of 3000 pc/cm3. Two strong pulses dispersed at the DM of the known radio magnetar J1550–5418 where found, one occurring at the same time of an X-ray burst. This result is potentially interesting in the framework of magnetar models for FRBs.
New simultaneous X-ray and radio observations of the archetypal mode-switching pulsar PSR B0943+10 have been carried out with XMM-Newton and the LOFAR, LWA and Arecibo radio telescopes in November 2014. They allowed us to better constrain the X-ray spectral and variability properties of this pulsar and to detect, for the first time, the X-ray pulsations also during the X-ray-fainter mode. The combined timing and spectral analysis indicates that unpulsed non-thermal emission, likely of magnetospheric origin, and pulsed thermal emission from a small polar cap are present during both radio modes and vary in a correlated way.
Brain abscess is uncommon in paediatric population, but of clinical importance because of significant long-term morbidity and mortality. In this multicentre study, promoted by the Italian Society for Paediatric Infectious Diseases, we retrospectively collected patients aged 0–18 years, with a diagnosis of ‘brain abscess’. Seventy-nine children were included; the median age was 8·75 years. As predisposing factor, 44 children had preceding infections. The Gram-positive cocci were mostly isolated (27 cases). Sixty (76%) children underwent a surgical intervention. Intravenous antibiotic therapy was administered in all patients, then switched to oral treatment. Clinical sequelae were recorded in 31 (39·2%) children. Twenty-one of them had a single sequela, of which, the most represented, was epilepsy in nine of them. This study focus the attention on the need to have standardized national guidelines or adequate recommendations on type and duration of antibiotic treatment.
In recent years, a revolution in astronomical position measurements has been taking place with the advent of modern space techniques. These new techniques, which supplement the traditional astrometric measurements, include laser ranging to the moon and artificial satellites, very-long-baseline interferometry (VLBI) of galactic and extra-galactic radio sources and spacecraft, radio tracking of satellites, and radar-ranging and spacecraft tracking during planetary encounters. Impressive accuracies have been achieved and further improvements are forthcoming. Each technique can be expected to establish its own reference frame which is derived from observations of a particular class of objects. The celestial and terrestrial coordinate systems are related through adopted constants and definitions. Contemporary astronomy has led to the development of three principal celestial coordinate systems: the optical frame (FK4/FK5) based on positions of galactic stars; the planetary/lunar ephemeris frame based on the major celestial bodies of the solar system; and the radio frame constructed from observations of extragalactic radio sources (quasars). Each frame is rotated with respect to others; furthermore, the optical frame offset is time variable. It is important that all frames be interconnected and unified. The optical frame is being connected to the radio frame by VLBI observations of radio emitting stars. The radio frame is being tied to the ephemeris frame in several ways – one is via differential VLBI measurements between quasars and planet-orbiting spacecraft.
Drug-resistant paediatric tuberculosis (TB) is an overlooked global problem. In Italy, the epidemiology of TB has recently changed and data regarding drug-resistant forms in the paediatric setting is scanty. The aim of this case series was to report the cases of drug-resistant TB, diagnosed between June 2006 and July 2010 in four Italian tertiary centres for paediatric infectious diseases, in children and adolescents living in Italy. Twenty-two children were enrolled, of these 17 were resistant to one or more drugs and five had multidrug-resistant TB. All but one child were either foreign born or had at least one foreign parent. Twenty-one patients completed their treatment without clinical or radiological signs of activity at the end of treatment, and one patient was lost to follow up. The outcomes were good, with few adverse effects using second-line anti-TB drugs. Although this series is limited, it might already reflect the worrisome increase of drug-resistant TB, even in childhood.
We utilized the new high-order (250-378 mode) Magellan Adaptive Optics system (MagAO) to obtain very high-resolution science in the visible with MagAO's VisAO CCD camera. In the good-median seeing conditions of Magellan (0.5–0.7″) we find MagAO delivers individual short exposure images as good as 19 mas optical resolution. Due to telescope vibrations, long exposure (60s) r' (0.63μm) images are slightly coarser at FWHM = 23-29 mas (Strehl ~ 28%) with bright (R < 9 mag) guide stars. These are the highest resolution filled-aperture images published to date. Images of the young (~ 1 Myr) Orion Trapezium θ1 Ori A, B, and C cluster members were obtained with VisAO. In particular, the 32 mas binary θ1 Ori C1C2 was easily resolved in non-interferometric images for the first time. Relative positions of the bright trapezium binary stars were measured with ~ 0.6–5 mas accuracy. In the second commissioning run we were able to correct 378 modes and achieved good contrasts (Strehl>20% on young transition disks at Hα). We discuss the contrasts achieved at Hα and the possibility of detecting low mass (~ 1–5 Mjup) planets (past 5AU) with our new SAPPHIRES survey with MagAO at Hα.
The Magellan Adaptive Optics (MagAO) system saw first light in November 2012 at Las Campanas Observatory (LCO) on the 6.5m Clay telescope. Here we present an introduction to MagAO's visible wavelength diffraction limited imager, VisAO. VisAO delivers Strehl ratios greater than 30% from 0.62 microns (r') through 1 micron, where Strehl is even higher, and achieved resolutions as small as 20 milli-arcseconds. We took advantage of the excellent performance of MagAO/VisAO to conduct high contrast observations of an exoplanet in the optical. With VisAO, we are, for the first time, able to begin characterizing exoplanet atmospheres in the optical from the ground.
We present the first ground-based adaptive optics images of a silhouette disk. This disk, Orion 218-354, is seen in silhouette against the bright nebular background of Orion, and was resolved using the new Magellan Adaptive Secondary AO system and its VisAO camera in Simultaneous Differential Imaging (SDI) mode. PSF subtraction of Orion 218-354 reveals a disk ~1″ (400 AU) in radius, with the degree of absorption increasing steadily towards the center of the disk. By virtue of the central star being unsaturated, these data probe inward to a much smaller radius than previous HST images. Our data present a different picture than previous observers had hypothesized, namely that the disk is likely optically thin at Hα at least as far inward as ~20AU. In addition to being among the first high-resolution AO images taken in the optical on a large telescope, these data reveal the power of SDI imaging to illuminate disk structure, and speak to a bright future for visible AO imaging. Analysis of the results described briefly here can be found in full detail in Follette et al. (2013).
MagAO is the newly-commissioned adaptive optics (AO) instrument on the Magellan Clay telescope at Las Companas Observatory, Chile. MagAO has two co-mounted science cameras: VisAO for visible-light direct and spectral-differential imaging; and Clio for near to thermal IR direct imaging, non-redundant-mask interference, and prism spectroscopy. We demonstrate MagAO's simultaneous visible and infrared AO performance via direct images of exoplanet Beta Pictoris b. The planet was detected in 5 passbands from 0.9–5μm. Here we show the infrared images; the visible observations are presented in Males et al. 2013. MagAO is the first AO system to offer good performance with extensive coverage across the O/IR spectrum and thus offers an unprecedented opportunity to study the spectral energy distributions of directly-imaged extrasolar planetary atmospheres.
The morphology of the sperm head has often been correlated with the outcome of in vitro fertilization, and has been shown to be the sole parameter in semen of value in predicting the success of intracytoplasmic sperm injection and intracytoplasmic morphologically selected sperm injection.
In this paper, we have studied whether digital holographic microscopy (DHM) may be useful to obtain quantitative data on human sperm head structure and compared this technique with high-power digitally enhanced Nomarski optics. The main advantage of digital holography is that high-resolution three-dimensional quantitative sample imaging may be automatically produced by numerical refocusing of a two-dimensional image at different object planes without any mechanical scanning. We show that DHM generates useful information on the dimensions and structure of human sperm, not revealed by conventional phase-contrast microscopy, in particular the volume of vacuoles, and suggest its use as an additional prognostic tool in assisted reproduction technology.
It has been shown before that the Rapidly Exploring Random Tree (RRT) algorithm is probabilistically and resolution complete; and that the probability of finding a particular solution path can be related to the number of nodes. However, little analysis exists on the rate at which the tree covers the configuration space. In this paper, we present a stochastic difference equation which models how the tree covers the configuration space as a function of the number of nodes in the tree. Using two simplifying assumptions, appropriate for holonomic, kinematic systems in expansive configuration spaces, we derive closed-form solutions for the expected value and variance of configuration space coverage, which only depend on two easily computable parameters. Using a grid-based coverage measurement, we present experimental evidence supporting this model across a range of dimensions, obstacle densities, and parameter choices. Collecting data from 1000 RRTs, we provide evidence that configuration space coverage concentrates tightly around the expected coverage predicted by the model; and the results of the Chi-squared test suggest that the distribution of coverage across these runs is highly Gaussian. Together these results enable one to predict the expected coverage, along with a confidence interval, after a certain number of nodes have been added to the tree. We also applied the model to an example with extremely narrow passages and to a system with non-holonomic kinematics. The expected value prediction is still qualitatively accurate; but the rate constant is reduced and the variance is higher. Overall, in addition to its theoretical value, the model may find future application as an online measure of search-progress and problem difficulty, useful for adaptive variants of the basic RRT algorithm.
Gujarati and White Hmong are among a small handful of languages known to maintain a phonemic contrast between breathy and modal voice across both obstruents and vowels. Given that breathiness on stop consonants is realized as a breathy-voiced aspirated release into the following vowel, how is consonant breathiness distinguished from vocalic breathiness, if at all? We examine acoustic and electroglottographic data of potentially ambiguous CV sequences collected from speakers of Gujarati and White Hmong, to determine what properties reliably distinguish breathiness associated with stop consonants from breathiness associated with vowels comparing both within and across these two unrelated languages. Results from the two languages are strikingly similar: only the early timing and increased magnitude of the various acoustic reflexes of breathiness phonetically distinguish phonemic consonantal breathiness from phonemic vocalic breathiness.
We report on the long term X-ray monitoring with Swift, RXTE, Suzaku, Chandra, and XMM-Newton of the outburst of the newly discovered magnetar Swift J1822.3–1606 (SGR 1822-1606), from the first observations soon after the detection of the short X-ray bursts which led to its discovery (July 2011), through the first stages of its outburst decay (April 2012). Our X-ray timing analysis finds the source rotating with a period of P = 8.43772016(2) s and a period derivative Ṗ = 8.3(2) × 10−14 ss−1, which entails an inferred dipolar surface magnetic field of B ≃ 2.7 × 1013 G at the equator. This measurement makes Swift J1822.3–1606 the second lowest magnetic field magnetar (after SGR 0418+5729; Rea et al. 2010). Following the flux and spectral evolution from the beginning of the outburst, we find that the flux decreased by about an order of magnitude, with a subtle softening of the spectrum, both typical of the outburst decay of magnetars. By modeling the secular thermal evolution of Swift J1822.3–1606, we find that the observed timing properties of the source, as well as its quiescent X-ray luminosity, can be reproduced if it was born with a poloidal and crustal toroidal fields of Bp ~ 1.5 × 1014 G and Btor ~ 7 × 1014 G, respectively, and if its current age is ~550 kyr (Rea et al. 2012).
The assessment of the radiological impact of a decommissioned
nuclear power plant is presented here through the results of an
environmental monitoring survey carried out in the area surrounding
the Garigliano Power Plant. The levels of radioactivity in soil,
water, air and other environmental matrices are shown, in which
α, β and γ activity and the γ equivalent dose rate are measured.
Radioactivity levels of the samples from the Garigliano area are
analyzed and then compared with those from a control zone situated
more than 100 km away. Moreover, a comparison is made with a previous survey
carried out in 2001. The analyses and comparisons show no significant
alteration in the radiological characteristics of the area surrounding
the plant, with the overall radioactivity depending mainly on the
global fallout and natural sources.
Low-grade inflammation is a characteristic of the obese state, and adipose tissue releases many inflammatory mediators. The source of these mediators within adipose tissue is not clear, but infiltrating macrophages seem to be especially important, although adipocytes themselves play a role. Obese people have higher circulating concentrations of many inflammatory markers than lean people do, and these are believed to play a role in causing insulin resistance and other metabolic disturbances. Blood concentrations of inflammatory markers are lowered following weight loss. In the hours following the consumption of a meal, there is an elevation in the concentrations of inflammatory mediators in the bloodstream, which is exaggerated in obese subjects and in type 2 diabetics. Both high-glucose and high-fat meals may induce postprandial inflammation, and this is exaggerated by a high meal content of advanced glycation end products (AGE) and partly ablated by inclusion of certain antioxidants or antioxidant-containing foods within the meal. Healthy eating patterns are associated with lower circulating concentrations of inflammatory markers. Among the components of a healthy diet, whole grains, vegetables and fruits, and fish are all associated with lower inflammation. AGE are associated with enhanced oxidative stress and inflammation. SFA and trans-MUFA are pro-inflammatory, while PUFA, especially long-chain n-3 PUFA, are anti-inflammatory. Hyperglycaemia induces both postprandial and chronic low-grade inflammation. Vitamin C, vitamin E and carotenoids decrease the circulating concentrations of inflammatory markers. Potential mechanisms are described and research gaps, which limit our understanding of the interaction between diet and postprandial and chronic low-grade inflammation, are identified.