Particle field holography data reduction by Fourier transform analysis

The size distribution of a particle field hologram is obtained with a Fourier transformation of the Fraunhofer diffraction pattern of the reconstructed hologram. Off-axis absorption holograms of particle fields with known characteristics were obtained and analyzed with a commercially available instrument. The mean particle size of the reconstructed hologram was measured with an error of + or - 5 percent, while the distribution broadening was estimated within + or - 15 percent. Small sections of a pulsed laser hologram of a synthetic fuel spray were analyzed with this method thus yielding a spatially resolved size distribution. The method yields fast and accurate automated analysis of particle field holograms

Partial Refunds or Money-Back Guarantees ?

A partial-refund policy is superior to a "full money-back policy when a seller faces a significant amount of opportunistic return behavior-i.e., consumers order a product for short term usage only to return it for a refund later. In a partial-refund policy, the seller charges a rent (the nonrefundable portion of price) to those who return the product; this discourages opportunistism, but also penalizes consumers who only return because merchandise is unsatisfactory. The optimal partial refund policy balances this tradeoff. Profit is higher under the partial refund policy because of a lower number of returns and because a higher price can be charged. Mail-order clothing and personal computer industries demonstrate that catalogers typically offer only partial refunds

Designer Reagents for Mass Spectrometry-Based Proteomics: Clickable Cross-Linkers for Elucidation of Protein Structures and Interactions

We present novel homobifunctional amine-reactive clickable cross-linkers (CXLs) for investigation of three-dimensional protein structures and protein–protein interactions (PPIs). CXLs afford consolidated advantages not previously available in a simple cross-linker, including (1) their small size and cationic nature at physiological pH, resulting in good water solubility and cell-permeability, (2) an alkyne group for bio-orthogonal conjugation to affinity tags via the click reaction for enrichment of cross-linked peptides, (3) a nucleophilic displacement reaction involving the 1,2,3-triazole ring formed in the click reaction, yielding a lock-mass reporter ion for only clicked peptides, and (4) higher charge states of cross-linked peptides in the gas-phase for augmented electron transfer dissociation (ETD) yields. Ubiquitin, a lysine-abundant protein, is used as a model system to demonstrate structural studies using CXLs. To validate the sensitivity of our approach, biotin-azide labeling and subsequent enrichment of cross-linked peptides are performed for cross-linked ubiquitin digests mixed with yeast cell lysates. Cross-linked peptides are detected and identified by collision induced dissociation (CID) and ETD with linear quadrupole ion trap (LTQ)-Fourier transform ion cyclotron resonance (FTICR) and LTQ-Orbitrap mass spectrometers. The application of CXLs to more complex systems (e.g., in vivo cross-linking) is illustrated by Western blot detection of Cul1 complexes including known binders, Cand1 and Skp2, in HEK 293 cells, confirming good water solubility and cell-permeability

Evaluating landscape metrics for characterising hydrological response to storm events in urbanised catchments

Hydrological response of an urban catchment to storm events is determined by a number of factors including the degree of urbanisation and distribution and connectivity of urbanised surfaces. Therefore, the ability of spatially averaged catchment descriptors to characterise storm response is limited. Landscape metrics, widely used in ecology to quantify landscape structure, are employed to quantify urban land-cover patterns across a rural-urban gradient of catchments and attribute hydrological response. Attribution of all response metrics, except peak flow, is improved by combining lumped catchment descriptors with spatially explicit landscape metrics. Those representing connectedness and shape of suburban and natural greenspace improve characterisation of percentage runoff and storm runoff. Connectivity and location of urban surfaces are more important than impervious area alone for attribution of timing, validating findings from distributed hydrological modelling studies. Findings suggest potential improvements in attribution of storm runoff in ungauged urban catchments using landscape metrics

A Self-Consistent Microscopic Theory of Surface Superconductivity

The electronic structure of the superconducting surface sheath in a type-II superconductor in magnetic fields $H_{c2}<H<H_{c3}$ is calculated self-consistently using the Bogoliubov-de Gennes equations. We find that the pair potential $\Delta(x)$ exhibits pronounced Friedel oscillations near the surface, in marked contrast with the results of Ginzburg-Landau theory. The role of magnetic edge states is emphasized. The local density of states near the surface shows a significant depletion near the Fermi energy due to the development of local superconducting order. We suggest that this structure could be unveiled by scanning-tunneling microscopy studies performed near the edge of a superconducting sample.Comment: 12 pages, Revtex 3.0, 3 postscript figures appende

What is the effect of a decision aid in potentially vulnerable parents? Insights from the head CT choice randomized trial.

ObjectiveTo test the hypotheses that use of the Head CT Choice decision aid would be similarly effective in all parent/patient dyads but parents with high (vs low) numeracy experience a greater increase in knowledge while those with low (vs high) health literacy experience a greater increase in trust.MethodsThis was a secondary analysis of a cluster randomized trial conducted at seven sites. One hundred seventy-two clinicians caring for 971 children at intermediate risk for clinically important traumatic brain injuries were randomized to shared decision making facilitated by the DA (n = 493) or to usual care (n = 478). We assessed for subgroup effects based on patient and parent characteristics, including socioeconomic status (health literacy, numeracy and income). We tested for interactions using regression models with indicators for arm assignment and study site.ResultsThe decision aid did not increase knowledge more in parents with high numeracy (P for interaction [Pint ] = 0.14) or physician trust more in parents with low health literacy (Pint  = 0.34). The decision aid decreased decisional conflict more in non-white parents (decisional conflict scale, -8.14, 95% CI: -12.33 to -3.95; Pint  = 0.05) and increased physician trust more in socioeconomically disadvantaged parents (trust in physician scale, OR: 8.59, 95% CI: 2.35-14.83; Pint  = 0.04).ConclusionsUse of the Head CT Choice decision aid resulted in less decisional conflict in non-white parents and greater physician trust in socioeconomically disadvantaged parents. Decision aids may be particularly effective in potentially vulnerable parents

The neuroblast and angioblast chemotaxic factor SDF-1 (CXCL12) expression is briefly up regulated by reactive astrocytes in brain following neonatal hypoxic-ischemic injury

BACKGROUND: Stromal cell-derived factor 1 (SDF-1 or CXCL12) is chemotaxic for CXCR4 expressing bone marrow-derived cells. It functions in brain embryonic development and in response to ischemic injury in helping guide neuroblast migration and vasculogenesis. In experimental adult stroke models SDF-1 is expressed perivascularly in the injured region up to 30 days after the injury, suggesting it could be a therapeutic target for tissue repair strategies. We hypothesized that SDF-1 would be expressed in similar temporal and spatial patterns following hypoxic-ischemic (HI) injury in neonatal brain. RESULTS: Twenty-five 7-day-old C57BL/J mice underwent HI injury. SDF-1 expression was up regulated up to 7 days after the injury but not at the later time points. The chief sites of SDF-1 up regulation were astrocytes, their foot processes along blood vessels and endothelial cells. CONCLUSION: The localization of SDF-1 along blood vessels in the HI injury zone suggests that these perivascular areas are where chemotaxic signaling for cellular recruitment originates and that reactive astrocytes are major mediators of this process. The associated endothelium is likely to be the site for vascular attachment and diapedesis of CXCR4 receptor expressing cells to enter the injured tissue. Here we show that, relative to adults, neonates have a significantly smaller window of opportunity for SDF-1 based vascular chemotaxic recruitment of bone marrow-derived cells. Therefore, without modification, following neonatal HI injury there is only a narrow period of time for endogenous SDF-1 mediated chemotaxis and recruitment of reparative cells, including exogenously administered stem/progenitor cells

Research Data Supporting "Gyroid Optical Metamaterials: Calculating the Effective Permittivity of Multidomain Samples"

Data Supporting Publication "Gyroid Optical Metamaterials: Calculating the Effective Permittivity of Multidomain Samples"Swiss National Science Foundation, National Center of Competence in Research Bio-Inspired Materials, [200021_163220 and PZ00P2_168223], EPSRC [Cambridge NanoDTC EP/G037221/1, EP/L027151/1, and EP/G060649/1], ERC [LINASS 320503], European Union’s Horizon 2020 Research and Innovation Programme under the Marie Sklodowska-Curie [706329], Adolphe Merkle Foundatio