Two unusual silicoflagellate double skeletons

A study of silicoflagellate double skeletons revealed two unusual doublets that are illustrated and discussed here. One of these comprises two ten-sided Octactis skeletons that appear to form a doublet, but both in the same (apical) orientation. The other specimen is a double skeleton of Dictyocha that is slightly disarticulated, with a third, less robust skeleton in between. These unusual double skeletons suggest that there is much more to be learned about the formation of silicoflagellate skeletons and the reproductive processes in this protist grou

Use of a hydrological model for environmental management of the Usangu Wetlands, Tanzania

Wetlands / Rivers / Ecology / Environmental effects / Remote sensing / Hydrology / Simulation models / Water budget / Irrigated sites / Land cover / Time series analysis / Tanzania / Usangu Wetlands / Great Ruaha River

Upgrading a Social Media Strategy to Increase Twitter Engagement During the Spring Annual Meeting of the American Society of Regional Anesthesia and Pain Medicine.

Microblogs known as tweets are a rapid, effective method of information dissemination in health care. Although several medical specialties have described their Twitter conference experiences, Twitter-related data in the fields of anesthesiology and pain medicine are sparse. We therefore analyzed the Twitter content of 2 consecutive spring meetings of the American Society of Regional Anesthesia and Pain Medicine using publicly available online transcripts. We also examined the potential contribution of a targeted social media campaign on Twitter engagement during the conferences. The original Twitter meeting content was largely scientific in nature and created by meeting attendees, the majority of whom were nontrainee physicians. Physician trainees, however, represent an important and increasing minority of Twitter contributors. Physicians not in attendance predominantly contributed via retweeting original content, particularly picture-containing tweets, and thus increased reach to nonattendees. A social media campaign prior to meetings may help increase the reach of conference-related Twitter discussion

Mortality differences and inequalities within and between 'protected characteristics' groups, in a Scottish Cohort 1991-2009

Background: Little is known about the interaction between socio-economic status and 'protected characteristics' in Scotland. This study aimed to examine whether differences in mortality were moderated by interactions with social class or deprivation. The practical value was to pinpoint population groups for priority action on health inequality reduction and health improvement rather than a sole focus on the most deprived socioeconomic groups. Methods: We used data from the Scottish Longitudinal Study which captures a 5.3 % sample of Scotland and links the censuses of 1991, 2001 and 2011. Hazard ratios for mortality were estimated for those protected characteristics with sufficient deaths using Cox proportional hazards models and through the calculation of European age-standardised mortality rates. Inequality was measured by calculating the Relative Index of Inequality (RII). Results: The Asian population had a polarised distribution across deprivation deciles and was more likely to be in social class I and II. Those reporting disablement were more likely to live in deprived areas, as were those raised Roman Catholic, whilst those raised as Church of Scotland or as 'other Christian' were less likely to. Those aged 35-54 years were the least likely to live in deprived areas and were most likely to be in social class I and II. Males had higher mortality than females, and disabled people had higher mortality than non-disabled people, across all deprivation deciles and social classes. Asian males and females had generally lower mortality hazards than majority ethnic ('White') males and females although the estimates for Asian males and females were imprecise in some social classes and deprivation deciles. Males and females who reported their raised religion as Roman Catholic or reported 'No religion' had generally higher mortality than other groups, although the estimates for 'Other religion' and 'Other Christian' were less precise. Using both the area deprivation and social class distributions for the whole population, relative mortality inequalities were usually greater amongst those who did not report being disabled, Asians and females aged 35-44 years, males by age, and people aged <75 years. The RIIs for the raised religious groups were generally similar or too imprecise to comment on differences. Conclusions: Mortality in Scotland is higher in the majority population, disabled people, males, those reporting being raised as Roman Catholics or with 'no religion' and lower in Asians, females and other religious groups. Relative inequalities in mortality were lower in disabled than nondisabled people, the majority population, females, and greatest in young adults. From the perspective of intersectionality theory, our results clearly demonstrate the importance of representing multiple identities in research on health inequalities.Publisher PDFPeer reviewe

Vaudeville: A High Performance, Voice-Activated Teleconferencing Application

We present a voice-activated, hands-off, ATM-based video conferencing application. The application, called Vaudeville, features high quality NTSC video, voice-activated audio transmission, audio bridging of two audio streams, and voice-activated video switching. It supports multiple simultaneous multi-party conferences using a scalable multicast mechanism. We describe how Vaudeville was built using a component-based distributed programming environment. We also describe the algorithms used to contorl the audio and video of the applciation. Audio and video are encoded in hardware using an ATM hardware multimedia interface

Quantification of High-Resolution Lattice Images and Electron Holograms

Progress towards the quantification of high-resolution electron microscopy and electron holograms has been achieved using digital acquisition with a slow-scan charge-coupled device (CCD) camera. Two applications are described: the precise measurement of lattice-fringe spacings and the determination of the mean inner potential. Lattice images can be characterized by a finite sum of two-dimensional sinusoids. A new method for measurement of the frequency, amplitude and phase of each sinusoid, based on an interpolation technique in reciprocal space, is presented. The method offers considerably higher precision for measurement of lattice fringes than the optical bench and is applicable to images recorded with an electron dose of less than 1 el / Å2 and specimen areas as small as 8 Å across. The attainable precision is dependent on specimen characteristics, electron dose and the size of the measured area, and ranges from 0.001 Å to 0.05 Å. An improved method has also been developed for measurement of mean inner potential using digital off-axis electron holograms from 90° crystal wedges. The value of (-14.21 ± 0.16) V obtained for GaAs represents the most accurate measurement yet reported for the mean inner potential

Is early center-based child care associated with tantrums and unmanageable behavior over time up to school entry?

Background. Existing research suggests that there is a relationship between greater exposure to center-based child care and child behavioral problems though the mechanism for the impact is unclear. However the measure used to document child care has usually been average hours, which may be particularly unreliable in the early months when fewer children are in center care. In addition individual trajectories for behavior difficulties have not been studied. Objective. The purpose of the current study was to examine whether the extent of exposure to center-based child care before two years predicted the trajectory of children’s difficult behavior (i.e., tantrums and unmanageable behavior) from 30 to 51 months controlling for child and maternal characteristics. Method. Data were drawn from UK-based Families, Children and Child Care (FCCC) study (n=1201). Individual growth models were fitted to test the relation between early center-based child care experiences and subsequent difficult behavior. Results. Children with more exposure to center-based care before two had less difficult behavior at 30 months, but more increase over time. Initial levels were predicted by higher difficult temperament and lower verbal ability. Higher difficult temperament and lower family socio-economic status predicted its change over time. Conclusion. Findings suggest that early exposure to center-based care before two years old is a risk factor for subsequent behavior problems especially when children have a longer period of exposure. A possible explanatory process is that child coping strategies to manage frustration are less well developed in a group context, especially when they lag behind in expressive language

Eutectic Colony Formation: A Stability Analysis

Experiments have widely shown that a steady-state lamellar eutectic solidification front is destabilized on a scale much larger than the lamellar spacing by the rejection of a dilute ternary impurity and forms two-phase cells commonly referred to as `eutectic colonies'. We extend the stability analysis of Datye and Langer for a binary eutectic to include the effect of a ternary impurity. We find that the expressions for the critical onset velocity and morphological instability wavelength are analogous to those for the classic Mullins-Sekerka instability of a monophase planar interface, albeit with an effective surface tension that depends on the geometry of the lamellar interface and, non-trivially, on interlamellar diffusion. A qualitatively new aspect of this instability is the occurence of oscillatory modes due to the interplay between the destabilizing effect of the ternary impurity and the dynamical feedback of the local change in lamellar spacing on the front motion. In a transient regime, these modes lead to the formation of large scale oscillatory microstructures for which there is recent experimental evidence in a transparent organic system. Moreover, it is shown that the eutectic front dynamics on a scale larger than the lamellar spacing can be formulated as an effective monophase interface free boundary problem with a modified Gibbs-Thomson condition that is coupled to a slow evolution equation for the lamellar spacing. This formulation provides additional physical insights into the nature of the instability and a simple means to calculate an approximate stability spectrum. Finally, we investigate the influence of the ternary impurity on a short wavelength oscillatory instability that is already present at off-eutectic compositions in binary eutectics.Comment: 26 pages RevTex, 14 figures (28 EPS files); some minor changes; references adde