290 research outputs found
Remote brainstorming: Methodological interventions in designing from a distance
This paper examines the immediate effects of group methods in facilitating remote team collaboration. We recruited seven teams with prior experience working together. All teams completed two current, complex, and open-ended design challenges using remote tools. We examined design activities before and after teams were given a design method intervention. The interventions were a Brainstorming Method to promote divergent thinking and the Five-Whys method to promote analytical thinking. Using OpenFace, we observed changes in emotion by examining facial expressions. We found that the brainstorming intervention did not have a change in ideation performance and the problem analysis intervention had a decrease in ideation performance. Teams used digital media to facilitate communication but were constrained by the media\u27s tools. Our results can inform teams in organizations interested in promoting divergent thinking to not expect immediate improvements in ideation performance following the introduction of a design method. Future research is required to identify relevant abilities and social skills needed to facilitate remote ideation through design methods
Quantum inference of states and processes
The maximum-likelihood principle unifies inference of quantum states and
processes from experimental noisy data. Particularly, a generic quantum process
may be estimated simultaneously with unknown quantum probe states provided that
measurements on probe and transformed probe states are available. Drawbacks of
various approximate treatments are considered.Comment: 7 pages, 4 figure
Entanglement and Timing-Based Mechanisms in the Coherent Control of Scattering Processes
The coherent control of scattering processes is considered, with electron
impact dissociation of H used as an example. The physical mechanism
underlying coherently controlled stationary state scattering is exposed by
analyzing a control scenario that relies on previously established entanglement
requirements between the scattering partners. Specifically, initial state
entanglement assures that all collisions in the scattering volume yield the
desirable scattering configuration. Scattering is controlled by preparing the
particular internal state wave function that leads to the favored collisional
configuration in the collision volume. This insight allows coherent control to
be extended to the case of time-dependent scattering. Specifically, we identify
reactive scattering scenarios using incident wave packets of translational
motion where coherent control is operational and initial state entanglement is
unnecessary. Both the stationary and time-dependent scenarios incorporate
extended coherence features, making them physically distinct. From a
theoretical point of view, this work represents a large step forward in the
qualitative understanding of coherently controlled reactive scattering. From an
experimental viewpoint, it offers an alternative to entanglement-based control
schemes. However, both methods present significant challenges to existing
experimental technologies
Mechanism and specificity of pentachloropseudilin-mediated inhibition of myosin motor activity.
Here, we report that the natural compound pentachloropseudilin (PClP) acts as a reversible and allosteric inhibitor of myosin ATPase and motor activity. IC(50) values are in the range from 1 to 5 μm for mammalian class-1 myosins and greater than 90 μm for class-2 and class-5 myosins, and no inhibition was observed with class-6 and class-7 myosins. We show that in mammalian cells, PClP selectively inhibits myosin-1c function. To elucidate the structural basis for PClP-induced allosteric coupling and isoform-specific differences in the inhibitory potency of the compound, we used a multifaceted approach combining direct functional, crystallographic, and in silico modeling studies. Our results indicate that allosteric inhibition by PClP is mediated by the combined effects of global changes in protein dynamics and direct communication between the catalytic and allosteric sites via a cascade of small conformational changes along a conserved communication pathway
Human Secretory IgM Emerges from Plasma Cells Clonally Related to Gut Memory B Cells and Targets Highly Diverse Commensals
Secretory immunoglobulin A (SIgA) enhances host-microbiota symbiosis, whereas SIgM remains poorly understood. We found that gut IgM+ plasma cells (PCs) were more abundant in humans than mice and clonally related to a large repertoire of memory IgM+ B cells disseminated throughout the intestine but rare in systemic lymphoid organs. In addition to sharing a gut-specific gene signature with memory IgA+ B cells, memory IgM+ B cells were related to some IgA+ clonotypes and switched to IgA in response to T cell-independent or T cell-dependent signals. These signals induced abundant IgM which, together with SIgM from clonally affiliated PCs, recognized mucus-embedded commensals. Bacteria recognized by human SIgM were dually coated by SIgA and showed increased richness and diversity compared to IgA-only-coated or uncoated bacteria. Thus, SIgM may emerge from pre-existing memory rather than newly activated naive IgM+ B cells and could help SIgA to anchor highly diverse commensal communities to mucus. Magri et al. found that the human gut includes a large memory IgM+ B cell repertoire clonally related to plasma cells mounting SIgM responses against mucus-embedded commensals co-targeted by SIgA. Dually coated bacteria are detected in humans but not mice and show increased diversity and richness compared to SIgA-only-coated or uncoated bacteria.</p
Human Secretory IgM Emerges from Plasma Cells Clonally Related to Gut Memory B Cells and Targets Highly Diverse Commensals
Secretory immunoglobulin A (SIgA) enhances host-microbiota symbiosis, whereas SIgM remains poorly understood. We found that gut IgM+ plasma cells (PCs) were more abundant in humans than mice and clonally related to a large repertoire of memory IgM+ B cells disseminated throughout the intestine but rare in systemic lymphoid organs. In addition to sharing a gut-specific gene signature with memory IgA+ B cells, memory IgM+ B cells were related to some IgA+ clonotypes and switched to IgA in response to T cell-independent or T cell-dependent signals. These signals induced abundant IgM which, together with SIgM from clonally affiliated PCs, recognized mucus-embedded commensals. Bacteria recognized by human SIgM were dually coated by SIgA and showed increased richness and diversity compared to IgA-only-coated or uncoated bacteria. Thus, SIgM may emerge from pre-existing memory rather than newly activated naive IgM+ B cells and could help SIgA to anchor highly diverse commensal communities to mucus. Magri et al. found that the human gut includes a large memory IgM+ B cell repertoire clonally related to plasma cells mounting SIgM responses against mucus-embedded commensals co-targeted by SIgA. Dually coated bacteria are detected in humans but not mice and show increased diversity and richness compared to SIgA-only-coated or uncoated bacteria.</p
Extrapulmonary small cell sarcinoma: involvement of the brain without evidence of extracranial malignancy by serial PET/CT scans
<p>Abstract</p> <p>Background</p> <p>Extrapulmonary small cell carcinoma (EPSCC) involving the brain is a rare manifestation of an uncommon tumor type.</p> <p>Case presentation</p> <p>We report a 59 year-old Caucasian female diagnosed with an EPSCC involving the left parietal lobe without detectable extracranial primary tumor followed by serial positron emission tomography/computed tomography (PET/CT) imaging. Histopathological examination at both initial presentation and recurrence revealed small cell carcinoma. Serial PET/CT scans of the entire body failed to reveal any extracranial [<sup>18</sup>F]2-fluoro-2-deoxy-D-glucose (FDG) avid lesions at either diagnosis or follow-up.</p> <p>Conclusion</p> <p>Chemotherapy may show a transient response in the treatment of EPSCC. Further studies are needed to help identify optimal treatment strategies. Combination PET/CT technology may be a useful tool to monitor EPSCC and assess for an occult primary malignancy.</p
Combined FDG-PET/CT for the detection of unknown primary tumors: systematic review and meta-analysis
The aim of this study was to systematically review and meta-analyze published data on the diagnostic performance of combined 18F-fluoro-2-deoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in the detection of primary tumors in patients with cancer of unknown primary (CUP). A systematic search for relevant studies was performed of the PubMed/MEDLINE and Embase databases. Methodological quality of the included studies was assessed. Reported detection rates, sensitivities and specificities were meta-analyzed. Subgroup analyses were performed if results of individual studies were heterogeneous. The 11 included studies, comprising a total sample size of 433 patients with CUP, had moderate methodological quality. Overall primary tumor detection rate, pooled sensitivity and specificity of FDG-PET/CT were 37%, 84% (95% CI 78–88%) and 84% (95% CI 78–89%), respectively. Sensitivity was heterogeneous across studies (P = 0.0001), whereas specificity was homogeneous across studies (P = 0.2114). Completeness of diagnostic workup before FDG-PET/CT, location of metastases of unknown primary, administration of CT contrast agents, type of FDG-PET/CT images evaluated and way of FDG-PET/CT review did not significantly influence diagnostic performance. In conclusion, FDG-PET/CT can be a useful method for unknown primary tumor detection. Future studies are required to prove the assumed advantage of FDG-PET/CT over FDG-PET alone and to further explore causes of heterogeneity
Sequence and expression pattern of the germ line marker vasa in honey bees and stingless bees
Queens and workers of social insects differ in the rates of egg laying. Using genomic information we determined the sequence of vasa, a highly conserved gene specific to the germ line of metazoans, for the honey bee and four stingless bees. The vasa sequence of social bees differed from that of other insects in two motifs. By RT-PCR we confirmed the germ line specificity of Amvasa expression in honey bees. In situ hybridization on ovarioles showed that Amvasa is expressed throughout the germarium, except for the transition zone beneath the terminal filament. A diffuse vasa signal was also seen in terminal filaments suggesting the presence of germ line cells. Oocytes showed elevated levels of Amvasa transcripts in the lower germarium and after follicles became segregated. In previtellogenic follicles, Amvasa transcription was detected in the trophocytes, which appear to supply its mRNA to the growing oocyte. A similar picture was obtained for ovarioles of the stingless bee Melipona quadrifasciata, except that Amvasa expression was higher in the oocytes of previtellogenic follicles. The social bees differ in this respect from Drosophila, the model system for insect oogenesis, suggesting that changes in the sequence and expression pattern of vasa may have occurred during social evolution
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