Boston Unplugged: Mapping a Wireless Future

Reviews a variety of models that would allow Boston to provide free or low-cost high-speed Internet access citywide. Outlines the benefits and mechanics of citywide WiFi, and lists factors to consider in designing, developing, and deploying a system

Feeding Sensitivity at 3-Months Predicts Parental Feeding Style at 3-Years

bjective: To examine the association between maternal responsive feeding in infancy and later parental feeding style in childhood, with a secondary aim of linking parenting style to child weight statusDesign: Short-term, longitudinal studySubjects: 65 mother-infant pairs, followed from 3-months to 3-yearsMethods: Mother-child dyads were seen at enrollment, observed at home when the infant was 3-months-old, and at home again when the infant turned 2-years of age. When the child reached 3-years, mothers self-reported their feeding style.Results: Responsive maternal feeding at 3-months predicted an authoritative feeding style at 3-years, and the authoritative feeding style was associated with a healthier weight status.Conclusion: Responsive feeding in infancy may serve as the foundation for responsive feeding in childhood and may serve to help in reducing obesity ris

Freehand Three-Dimensional Ultrasound to Evaluate Scapular Movement

Altered scapular kinematics have been linked to increases in shoulder pain and pathology. As such, identifying normal scapular movement is integral to preventing pathology and maintaining health of the joint. Existing methods to evaluate scapular movement are invasive, expensive, require exposure to radiation, suffer skin based motion artifacts, or allow for examination only in static postures. Freehand three-dimensional ultrasound offers the unique ability to image bone while being non-invasive, relatively low cost, and free of radiation. This is a novel application of a technology that in the past has been used for needle guided injections and determining changes in organ volumes, but never for evaluating bone movement. We have developed a custom freehand-ultrasound system that shows high repeatability across trials (SEM < 2°) in evaluating scapular kinematics in static postures with the arm at rest and elevated in the sagittal, frontal and scapular planes. Among manual wheelchair users and able-bodied controls we found scapular kinematics with the arm in an elevated position were predicted by scapular and trunk position at rest. We also found BMI ≥ 25, presence of pathology on a physical exam, shoulder abnormalities on a clinical ultrasound exam, and greater than 10 years of wheelchair use resulted in scapular postures associated with shoulder pathology in previous studies. We found no significant differences between wheelchair users and age-matched controls but attribute this to a lack of difference in pathology between the groups. A learning curve was identified over time for capturing quality ultrasound images and it is suggested future studies incorporate ample training time and require raters to meet minimum performance measures set forth by this study. In a subsample of subjects we found increases in external rotation, upward rotation and posterior tilting at incremental angles of humeral elevation during dynamic trials indicating that it is feasible to apply our methods to evaluate dynamic scapular movement. Application of these methods may help to identify shoulder pathology and evaluate the efficacy of interventions to correct altered scapular kinematics

Early Influences on the Development of Food Preferences

The ability to perceive flavors begins in utero with the development and early functioning of the gustatory and olfactory systems. Because both amniotic fluid and breast milk contain molecules derived from the mother’s diet, learning about flavors in foods begins in the womb and during early infancy. This early experience serves as the foundation for the continuing development of food preferences across the lifespan, and is shaped by the interplay of biological, social, and environmental factors. Shortly after birth, young infants show characteristic taste preferences: sweet and umami elicit positive responses; bitter and sour elicit negative responses. These taste preferences may reflect a biological drive towards foods that are calorie- and protein-dense and an aversion to foods that are poisonous or toxic. Early likes and dislikes are influenced by these innate preferences, but are also modifiable. Repeated exposure to novel or disliked foods that occurs in a positive, supportive environment may promote the acceptance of and eventually a preference for those foods. Alternatively, children who are pressured to eat certain foods may show decreased preference for those foods later on. With increasing age, the influence of a number of factors, such as peers and food availability, continue to mold food preferences and eating behaviors

Homologous Recombination in Negative Sense RNA Viruses

Recombination is an important process that influences biological evolution at many different levels. More and more homologous recombination events have been reported among negative sense RNA viruses recently. While sporadic authentic examples indicate that homologous recombination does occur, recombination seems to be generally rare or even absent in most negative sense RNA viruses, and most of the homologous recombination events reported in the literature were likely generated artificially due to lab contamination or inappropriate bioinformatics methods. Homologous recombination in negative sense RNA viruses should be reported with caution in the future, and only after stringent quality control efforts. Moreover, co-infection experiments should be performed to confirm whether recombination can occur

A Challenge to the Ancient Origin of SIVagm Based on African Green Monkey Mitochondrial Genomes

While the circumstances surrounding the origin and spread of HIV are becoming clearer, the particulars of the origin of simian immunodeficiency virus (SIV) are still unknown. Specifically, the age of SIV, whether it is an ancient or recent infection, has not been resolved. Although many instances of cross-species transmission of SIV have been documented, the similarity between the African green monkey (AGM) and SIVagm phylogenies has long been held as suggestive of ancient codivergence between SIVs and their primate hosts. Here, we present well-resolved phylogenies based on full-length AGM mitochondrial genomes and seven previously published SIVagm genomes; these allowed us to perform the first rigorous phylogenetic test to our knowledge of the hypothesis that SIVagm codiverged with the AGMs. Using the Shimodaira–Hasegawa test, we show that the AGM mitochondrial genomes and SIVagm did not evolve along the same topology. Furthermore, we demonstrate that the SIVagm topology can be explained by a pattern of west-to-east transmission of the virus across existing AGM geographic ranges. Using a relaxed molecular clock, we also provide a date for the most recent common ancestor of the AGMs at approximately 3 million years ago. This study substantially weakens the theory of ancient SIV infection followed by codivergence with its primate hosts

DNA Extraction from Dry Museum Beetles without Conferring External Morphological Damage

BACKGROUND: A large number of dry-preserved insect specimens exist in collections around the world that might be useful for genetic analyses. However, until now, the recovery of nucleic acids from such specimens has involved at least the partial destruction of the specimen. This is clearly undesirable when dealing with rare species or otherwise important specimens, such as type specimens. METHODOLOGY: We describe a method for the extraction of PCR-amplifiable mitochondrial and nuclear DNA from dry insects without causing external morphological damage. Using PCR to amplify ≈220 bp of the mitochondrial gene cytochrome c oxidase I, and 250–345 bp fragments of the multi-copy, nuclear 28s ribosomal DNA gene, we demonstrate the efficacy of this method on beetles collected up to 50 years ago. CONCLUSIONS: This method offers a means of obtaining useful genetic information from rare insects without conferring external morphological damage

Genesis and pathogenesis of the 1918 pandemic H1N1 influenza A virus

The source, timing, and geographical origin of the 1918–1920 pandemic influenza A virus have remained tenaciously obscure for nearly a century, as have the reasons for its unusual severity among young adults. Here, we reconstruct the origins of the pandemic virus and the classic swine influenza and (postpandemic) seasonal H1N1 lineages using a host-specific molecular clock approach that is demonstrably more accurate than previous methods. Our results suggest that the 1918 pandemic virus originated shortly before 1918 when a human H1 virus, which we infer emerged before ∼1907, acquired avian N1 neuraminidase and internal protein genes. We find that the resulting pandemic virus jumped directly to swine but was likely displaced in humans by ∼1922 by a reassortant with an antigenically distinct H1 HA. Hence, although the swine lineage was a direct descendent of the pandemic virus, the post-1918 seasonal H1N1 lineage evidently was not, at least for HA. These findings help resolve several seemingly disparate observations from 20th century influenza epidemiology, seroarcheology, and immunology. The phylogenetic results, combined with these other lines of evidence, suggest that the highmortality in 1918 among adults aged ∼20 to ∼40 y may have been due primarily to their childhood exposure to a doubly heterosubtypic putative H3N8 virus, which we estimate circulated from ∼1889–1900. All other age groups (except immunologically naive infants) were likely partially protected by childhood exposure to N1 and/or H1-related antigens. Similar processes may underlie age-specific mortality differences between seasonal H1N1 vs. H3N2 and human H5N1 vs. H7N9 infections

Co-evolutionary analysis suggests a role for TLR9 in papillomavirus restriction

Upon infection, DNA viruses can be sensed by pattern recognition receptors (PRRs) leading to the activation of type I and III interferons, aimed at blocking infection. Therefore, viruses must inhibit these signaling pathways, avoid being detected, or both. Papillomavirus virions are trafficked from early endosomes to the Golgi apparatus and wait for the onset of mitosis to complete nuclear entry. This unique subcellular trafficking strategy avoids detection by cytoplasmic PRRs, a property that may contribute to establishment of infection. However, as the capsid uncoats within acidic endosomal compartments, the viral DNA may be exposed to detection by toll-like receptor (TLR) 9. In this study we characterize two new papillomaviruses from bats and use molecular archeology to demonstrate that their genomes altered their nucleotide composition to avoid detection by TLR9, providing evidence that TLR9 acts as a PRR during papillomavirus infection. Furthermore, we demonstrate that TLR9, like other components of the innate immune system, is under evolutionary selection in bats, providing the first direct evidence for co-evolution between papillomaviruses and their hosts