An Experimental Study of the Wake of a Turbulent Boundary Layer Junction Flow

An experimental study of the wake of a turbulent boundary layer junction flow was performed using a 3:2 elliptical nose and NACA 0020 tail airfoil in the Flow Physics Facility at the University of New Hampshire. An eight-wire enstrophy hot-wire probe was used to measure all three components of velocity and vorticity at four downstream measurement planes from 1 cord length to 33 cord lengths behind the airfoil. In addition, a simple fairing was added to the airfoil, and the same experiments were repeated. The friction velocity was measured afterward by a Preston tube experiment at the same measurement locations. The incoming flow had a momentum thickness Reynolds number of Re_θ=19600. It was found that the streamwise velocity statistics in the near measurement planes matched previous junction flow observations. The other velocity statistics supported the conclusions and knowledge in the near planes. The vorticity variance measurements showed little variation from the undisturbed boundary layer leading to the conclusion that large-scale motions are primarily responsible for the non-equilibrium aspects of the flow. The downstream measurements clarified the recovery process towards the undisturbed boundary layer. The final measurement plane showed that aspects of the flow had fully recovered, while others had not. The Reynold stress showed that the turbulent structure of the flow had not recovered but remained persistently different from the undisturbed case. The airfoil with the fairing supported the observations of the airfoil case. Differences were seen between the airfoil and the airfoil with the fairing, but due to the coarse measurement plane, no conclusions were made

The Relationship Between Diet Quality, Micronutrient Content and Sleep Indices in Children Ages 9-11

Physiological factors such as metabolism, circadian rhythms, and hormone production play an important role in sleep quality. The physiology of sleep is significantly modified by externally mediated factors, such as socioeconomic status and the quality of nutrition. Sleep actigraphy records from a sub-sample of school-age participants in the Syracuse Lead Study (n=125) were used to evaluate the impact of diet on sleep quality and efficiency. Sleep duration, efficiency, latency, and fragmentation were extracted from actigraphy records over 5 consecutive weekdays. Healthy Eating Index 2015 (HEI-2015) scores and component sub-scores were calculated from two 24-hour recalls per participant collected through the Automated Self-Administered 24-hour Dietary Assessment Tool (ASA 24) and completed within one week of actigraphy on a consecutive Friday and Saturday for each participant.As to be expected, sleep efficiency and fragmentation showed strong associations with sleep duration. No significant correlations in sleep parameters were observed with total HEI score. The HEI sub-scores for saturated fat (r = 0.200, p = 0.026) and sodium (r = 0.191, p = 0.033) had a positive relationship with sleep efficiency. Additionally, total fat was positively correlated with fragmentation (r = 0.233, p = 0.009) and total activity (r = 0.191, p = 0.032). Greater energy intake (kcals) appeared alongside increased fragmentation (r = 0.179, p = 0.046). SES had a significant effect on duration (r = 0.1814 p = 0.040), efficiency (r = 0.208, p = 0.020), fragmentation (r = -0.253, p = 0.004) and total activity (r = -0.200, p = 0.026). Nutrient analysis from dietary recalls found total fat (r = -0.153, p = 0.044) and sodium (r = -0.177, p = 0.024) showed an inverse relationship with sleep efficiency, while total fat (r = 0.232, p = 0.005). and magnesium (r = 0.190, p = 0.017) were positively correlated with fragmentation. There were also differences between race, with Black participants found be living at a lower SES (r = -0.208, p = 0.010). White participants in the study, however, experienced greater sleep fragmentation (p = 0.030), lower HEI total scores (p = 0.007) and higher saturated fat intake (p = 0.003). Hierarchical linear regression was used to determine if these variables explained a statistically significant amount of variance in sleep efficiency and fragmentation after accounting for the fixed factors of socioeconomic status (SES), age, race, gender, and body mass index. The fixed factors accounted for 7.7% of the variability in sleep efficiency, with dietary factors controlling an additional 5.7%; the overall contribution to sleep efficiency was not statistically significant [R2=0.134, F (12,112) =1.45, p=0.154). Fixed factors accounted for 12.9% of the total variation in sleep fragmentation, with diet contributing to an additional 9.8%. The overall model contribution to sleep fragmentation is statistically significant [R2=0.226, F (12, 112) =2.73, p=0.003]. Overall, diet contributed to sleep less than race and SES, with saturated fat being the most significant dietary component

Inserting Oneself in the Story: Queer Literacy, Comics, and an Admonition to Move

Inserting Oneself in the Story: Queer Literacy, Comics, and an Admonition to Mov

Engineering ClpS for enhanced N-terminal amino acid binding and use in peptide sequencing

As different single-molecule protein sequencing technologies emerge, the need for reagents that can selectively recognized and detect amino acids with high affinity has become apparent. Naturally occurring proteins that function through recognition of amino (N)-terminal amino acids (NAAs), such as the N-end rule pathway adaptor protein ClpS can be engineered for enhanced affinity and specificity to meet this requirement. The native ClpS protein has a high specificity albeit modest affinity for the amino acid Phe at the N-terminus but also recognizes other residues at the N-terminal position. We employed directed evolution methods to select for ClpS variants with enhanced affinity and selectivity for NAAs. In addition, we combined these mutations with rationally designed mutations to improve the thermal stability of the protein. The results and their possible implication to peptide sequencing will be presented. Please click Additional Files below to see the full abstract

Reconstructing Cetacean Brain Evolution Using Computed Tomography

Until recently, there have been relatively few studies of brain mass and morphology in fossil cetaceans (dolphins, whales, and porpoises) because of difficulty accessing the matrix that fills the endocranial cavity of fossil cetacean skulls. As a result, our knowledge about cetacean brain evolution has been quite limited. By applying the noninvasive technique of computed tomography (CT) to visualize, measure, and reconstruct the endocranial morphology of fossil cetacean skulls, we can gain vastly more information at an unprecedented rate about cetacean brain evolution. Here, we discuss our method and demonstrate it with several examples from our fossil cetacean database. This approach will provide new insights into the little-known evolutionary history of cetacean brain evolution

Characterization of Maltese pottery of the Late Neolithic, Bronze Age and Punic Period by neutron activation analysis

A set of 41 samples from Tas-Silg, Malta, has been analysed by neutron activation. It contained nine ware groups formed by visual examination covering the Late Neolithic, Bronze Age and Punic Periods (c. 3000–218 BC). Despite this diversity and long time range, seven of these ware groups, including the ‘Thermi Ware’, all have a similar chemical composition and, therefore, have been made from the same clay. This points most probably to a local origin. One group from the Punic Period, containing only Bricky Red cooking ware, is chemically separate and represents a second distinct pattern probably assignable to a local production. Five amphora sherds also from the Punic Period, and consisting of a micaceous fabric, all have different chemical characteristics and are probably imports from overseas production sites of unknown location.peer-reviewe

Spatial chloroplast-to-nucleus signalling involving plastid-nuclear complexes and stromules

Communication between chloroplasts and the nucleus in response to various environmental cues may be mediated by various small molecules. Signalling specificity could be enhanced if the physical contact between these organelles facilitates direct transfer and prevents interference from other subcellular sources of the same molecules. Plant cells have plastidnuclear complexes, which provide close physical contact between these organelles. plastidnuclear complexes have been proposed to facilitate transfer of photosynthesis-derived H₂O₂ to the nucleus in high light. Stromules (stroma filled tubular plastid extensions) may provide an additional conduit for transfer of a wider range of signalling molecules, including proteins. However, plastid-nuclear complexes and stromules have been hitherto treated as distinct phenomena. We suggest that plastid-nuclear complexes and stromules work in a coordinated manner so that, according to environmental conditions or developmental state the two modes of connection contribute to varying extents. We hypothesise that this association is dynamic and that there may be a link between plastid-nuclear complexes and the development of stromules. Furthermore, the changes in contact could alter signalling specificity by allowing an extended or different range of signalling molecules to be delivered to the nucleus

How do valence and meaning interact? The contribution of semantic control

The hub‐and‐spoke model of semantic cognition proposes that conceptual representations in a heteromodal ‘hub’ interact with and emerge from modality‐specific features or ‘spokes’, including valence (whether a concept is positive or negative), along with visual and auditory features. As a result, valence congruency might facilitate our ability to link words conceptually. Semantic relatedness may similarly affect explicit judgements about valence. Moreover, conflict between meaning and valence may recruit semantic control processes. Here we tested these predictions using two‐alternative forced‐choice tasks, in which participants matched a probe word to one of two possible target words, based on either global meaning or valence. Experiment 1 examined timed responses in healthy young adults, while Experiment 2 examined decision accuracy in semantic aphasia patients with impaired controlled semantic retrieval following left hemisphere stroke. Across both experiments, semantically related targets facilitated valence matching, while related distractors impaired performance. Valence congruency was also found to facilitate semantic decision‐making. People with semantic aphasia showed impaired valence matching and had particular difficulty when semantically related distractors were presented, suggesting that the selective retrieval of valence information relies on semantic control processes. Taken together, the results are consistent with the hypothesis that automatic access to the global meaning of written words affects the processing of valence, and that the valence of words is also retrieved even when this feature is task‐irrelevant, affecting the efficiency of global semantic judgements

Why the US spends more treating high-need high-cost patients: a comparative study of pricing and utilization of care in six high-income countries.

One of the most pressing challenges facing most health care systems is rising costs. As the population ages and the demand for health care services grows, there is a growing need to understand the drivers of these costs across systems. This paper attempts to address this gap by examining utilization and spending of the course of a year for two specific high-need high-cost patient types: a frail older person with a hip fracture and an older person with congestive heart failure and diabetes. Data on utilization and expenditure is collected across five health care settings (hospital, post-acute rehabilitation, primary care, outpatient specialty and drugs), in six countries (Canada (Ontario), France, Germany, Spain (Aragon), Sweden and the United States (fee for service Medicare) and used to construct treatment episode Purchasing Power Parities (PPPs) that compare prices using baskets of goods from the different care settings. The treatment episode PPPs suggest other countries have more similar volumes of care to the US as compared to other standardization approaches, suggesting that US prices account for more of the differential in US health care expenditures. The US also differs with regards to the share of expenditures across care settings, with post-acute rehab and outpatient speciality expenditures accounting for a larger share of the total relative to comparators

Direct Nano-Imaging of Light-Matter Interactions in Nanoscale Excitonic Emitters

Strong light-matter interactions in localized nano-emitters when placed near metallic mirrors have been widely reported via spectroscopic studies in the optical far-field. Here, we report a near-field nano-spectroscopic study of the localized nanoscale emitters on a flat Au substrate. We observe strong-coupling of the excitonic dipoles in quasi 2-dimensional CdSe/CdxZnS1-xS nanoplatelets with gap mode plasmons formed between the Au tip and substrate. We also observe directional propagation on the Au substrate of surface plasmon polaritons launched from the excitons of the nanoplatelets as wave-like fringe patterns in the near-field photoluminescence maps. These fringe patterns were confirmed via extensive electromagnetic wave simulations to be standing-waves formed between the tip and the emitter on the substrate plane. We further report that both light confinement and the in-plane emission can be engineered by tuning the surrounding dielectric environment of the nanoplatelets. Our results lead to renewed understanding of in-plane, near-field electromagnetic signal transduction from the localized nano-emitters with profound implications in nano and quantum photonics as well as resonant optoelectronics.Comment: manuscript + supporting informatio