Capture and enrichment of CD34-positive haematopoietic stem and progenitor cells from blood circulation using P-selectin in an implantable device

Clinical infusion of haematopoietic stem and progenitor cells (HSPCs) is vital for restoration of haematopoietic function in many cancer patients. Previously, we have demonstrated an ability to mimic physiological cell trafficking in order to capture CD34-positive (CD34+) HSPCs using monolayers of the cell adhesion protein P-selectin in flow chambers. The current study aimed to determine if HSPCs could be captured directly from circulating blood in vivo. Vascular shunt prototypes, coated internally with P-selectin, were inserted into the femoral artery of rats. Blood flow through the cell capture device resulted in a wall shear stress of 4–6 dynes/cm2. After 1-h blood perfusion, immunofluorescence microscopy and flow cytometric analysis revealed successful capture of mononuclear cells positive for the HSPC surface marker CD34. Purity of captured CD34+ cells showed sevenfold enrichment over levels found in whole blood, with an average purity of 28%. Robust cell capture and HSPC enrichment were also demonstrated in devices that were implanted in a closed-loop arterio-venous shunt conformation for 2 h. Adherent cells were viable in culture and able to differentiate into burst-forming units. This study demonstrated an ability to mimic the physiological arrest of HSPCs from blood in an implantable device and may represent a practical alternative for adult stem cell capture and enrichment

Decreasing sprint duration from 20 to 10 s during reduced-exertion high-intensity interval training (REHIT) attenuates the increase in maximal aerobic capacity but has no effect on affective and perceptual responses

Purpose: Recent studies have demonstrated that modifying the ‘classic’ 6x30-s ‘all-out’ sprint interval training (SIT) protocol by incorporating either shorter sprints (6x10-s or 15-s sprints) or fewer sprints (e.g. 2x20-s sprints; reduced-exertion high-intensity interval training (REHIT)) does not attenuate the training-induced improvements in maximal aerobic capacity (V̇O2max). The aim of the present study was to determine whether reducing the sprint duration in the REHIT protocol from 20 s to 10 s per sprint influences acute affective responses and the change in V̇O2max following training. Methods: Thirty-six sedentary or recreationally active participants (17 women; mean±SD age: 22±3 y, BMI: 24.5±4.6 kg·m-2, V̇O2max: 37±8 mL·kg-1·min-1) were randomised to a group performing a ‘standard’ REHIT protocol involving 2x20-s sprints or a group who performed 2x10-s sprints. V̇O2max was determined before and after 6 weeks of 3 weekly training sessions. Acute affective responses and perceived exertion were assessed during training. Results: Greater increases in V̇O2max were observed for the group performing 20-s sprints (2.77±0.75 to 3.04±0.75 L·min-1; +10%) compared to the group performing 10-s sprints (2.58±0.57 vs. 2.67±3.04 L·min-1; +4%; group×time interaction effect: p<0.05; d=1.06). Positive affect and the mood state vigour increased post-exercise, while tension, depression and total mood disturbance decreased, and negative affect remained unchanged. Affective responses and perceived exertion were not altered by training and were not different between groups. Conclusion: Reducing sprint duration in the REHIT protocol from 20 s to 10 s attenuates improvements in V̇O2max, and does not result in more positive affective responses or lower perceived exertion

Genetic diversity analysis of common beans based on molecular markers

A core collection of the common bean (Phaseolus vulgaris L.), representing genetic diversity in the entire Mexican holding, is kept at the INIFAP (Instituto Nacional de Investigaciones Forestales, Agricolas y Pecuarias, Mexico) Germplasm Bank. After evaluation, the genetic structure of this collection (200 accessions) was compared with that of landraces from the states of Oaxaca, Chiapas and Veracruz (10 genotypes from each), as well as a further 10 cultivars, by means of four amplified fragment length polymorphisms (AFLP) +3/+3 primer combinations and seven simple sequence repeats (SSR) loci, in order to define genetic diversity, variability and mutual relationships. Data underwent cluster (UPGMA) and molecular variance (AMOVA) analyses. AFLP analysis produced 530 bands (88.5% polymorphic) while SSR primers amplified 174 alleles, all polymorphic (8.2 alleles per locus). AFLP indicated that the highest genetic diversity was to be found in ten commercial-seed classes from two major groups of accessions from Central Mexico and Chiapas, which seems to be an important center of diversity in the south. A third group included genotypes from Nueva Granada, Mesoamerica, Jalisco and Durango races. Here, SSR analysis indicated a reduced number of shared haplotypes among accessions, whereas the highest genetic components of AMOVA variation were found within accessions. Genetic diversity observed in the common-bean core collection represents an important sample of the total Phaseolus genetic variability at the main Germplasm Bank of INIFAP. Molecular marker strategies could contribute to a better understanding of the genetic structure of the core collection as well as to its improvement and validation

Infant screen exposure links to toddlers' inhibition, but not other EF constructs: a propensity score study

Technology is pervasive in homes of families with young children, despite evidence for negative associations between infant exposure to screen-based media and cognitive development that has led the American Academy of Pediatrics (AAP) to discourage parents from exposing children under the age of 18 months to any kind of screen time (AAP, 2016). Here, we apply a propensity score matching approach to estimate relations between electronic screen-based media use in infancy and executive function in early toddlerhood. In an international sample of 416 firstborn infants, parental report of regular exposure to screen-based media at 4 months predicted poorer performance on a test of inhibition at 14 months, but was unrelated to either cognitive flexibility or working memory at 14 months. Results of this study are therefore consistent with the view that early exposure to screen-based media adversely affects the development of executive function.Education and Child Studie

Designing Social Agents with Empathic Understanding

Abstract. This paper addresses the design of an agent model for a social agent capable of understanding other agents in an empathic way. The model describes how the empathic agent deals with another agent’s mental states and the associated feelings, thus not only understanding the other agent’s mental state but at the same time feeling the accompanying emotion of the other agent.

Observation of hard scattering in photoproduction events with a large rapidity gap at HERA

Events with a large rapidity gap and total transverse energy greater than 5 GeV have been observed in quasi-real photoproduction at HERA with the ZEUS detector. The distribution of these events as a function of the $\gamma p$ centre of mass energy is consistent with diffractive scattering. For total transverse energies above 12 GeV, the hadronic final states show predominantly a two-jet structure with each jet having a transverse energy greater than 4 GeV. For the two-jet events, little energy flow is found outside the jets. This observation is consistent with the hard scattering of a quasi-real photon with a colourless object in the proton.Comment: 19 pages, latex, 4 figures appended as uuencoded fil

Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio

Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS

The chi_b(nP) quarkonium states are produced in proton-proton collisions at the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS detector. Using a data sample corresponding to an integrated luminosity of 4.4 fb^-1, these states are reconstructed through their radiative decays to Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes. This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table, corrected author list, matches final version in Physical Review Letter

Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters