A systematic literature review of research on social procurement in the construction and infrastructure sector : barriers, enablers, and strategies

In Australia, a new feature of public policy is the requirement by governments that large-scale infrastructure projects integrate social procurement practices that alter the traditional focus on balancing price and quality. Social procurement has been gradually developing in practice, but the academic literature has not kept pace. Although past research has identified some of the barriers affecting social procurement implementation in the construction industry, the nature of the barriers impeding its proliferation has not to date been systematically reviewed. This paper undertakes a review of the social procurement literature published from January 2012 to 30 June 2022, with 49 papers chosen under selective criteria. This critical review employs the “Preferred Reporting Items for Systematic Reviews and Meta-Analyses” (PRISMA) technique to retrieve secondary data on social procurement from available peer-reviewed academic papers through three databases (Scopus, EBSCOhost, Web of Science). The literature analysis focuses on three themes: (1) barriers; (2) enablers; and (3) strategies to overcome the barriers. The paper finds that social procurement as a field of practice is evolving and expanding, but its role in contributing to social value creation remains an under-theorised concept. Recommendations for practice and future research are identified, including the need to measure the real-world impacts of policy

Minor differences in haplotype frequency estimates can produce very large differences in heterogeneity test statistics

<p>Abstract</p> <p>Background</p> <p>Tests for association between a haplotype and disease are commonly performed using a likelihood ratio test for heterogeneity between case and control haplotype frequencies. Using data from a study of association between heroin dependence and the DRD2 gene, we obtained estimated haplotype frequencies and the associated likelihood ratio statistic using two different computer programs, MLOCUS and GENECOUNTING. We also carried out permutation testing to assess the empirical significance of the results obtained.</p> <p>Results</p> <p>Both programs yielded similar, though not identical, estimates for the haplotype frequencies. MLOCUS produced a p value of 1.8*10^-15and GENECOUNTING produced a p value of 5.4*10^-4. Permutation testing produced a p value 2.8*10^-4.</p> <p>Conclusion</p> <p>The fact that very large differences occur between the likelihood ratio statistics from the two programs may reflect the fact that the haplotype frequencies for the combined group are not constrained to be equal to the weighted averages of the frequencies for the cases and controls, as they would be if they were directly observed rather than being estimated. Minor differences in haplotype frequency estimates can result in very large differences in the likelihood ratio statistic and associated <it>p </it>value.</p

Ultrasound-triggered disruption and self-healing of reversibly cross-linked hydrogels for drug delivery and enhanced chemotherapy

Foldable photoelectronics and muscle-like transducers require highly stretchable and transparent electrical conductors. Some conducting oxides are transparent, but not stretchable. Carbon nanotube films, graphene sheets and metal-nanowire meshes can be both stretchable and transparent, but their electrical resistances increase steeply with strain <100%. Here we present highly stretchable and transparent Au nanomesh electrodes on elastomers made by grain boundary lithography. The change in sheet resistance of Au nanomeshes is modest with a one-time strain of ~160% (from ~21 Ω per square to ~67 Ω per square), or after 1,000 cycles at a strain of 50%. The good stretchability lies in two aspects: the stretched nanomesh undergoes instability and deflects out-of-plane, while the substrate stabilizes the rupture of Au wires, forming distributed slits. Larger ratio of mesh-size to wire-width also leads to better stretchability. The highly stretchable and transparent Au nanomesh electrodes are promising for applications in foldable photoelectronics and muscle-like transducers.Engineering and Applied Science

Thermal Anomalies Detect Critical Global Land Surface Changes

Measurements that link surface conditions and climate can provide critical information on important biospheric changes occurring in the Earth system. As the direct driving force of energy and water fluxes at the surface–atmosphere interface, land surface temperature (LST) provides information on physical processes of land-cover change and energy-balance changes that air temperature cannot provide. Annual maximum LST (LSTmax) is especially powerful at minimizing synoptic and seasonal variability and highlighting changes associated with extreme climatic events and significant land-cover changes. The authors investigate whether maximum thermal anomalies from satellite observations could detect heat waves and droughts, a melting cryosphere, and disturbances in the tropical forest from 2003 to 2014. The 1-km2 LSTmax anomalies peaked in 2010 when 20% of the global land area experienced anomalies of greater than 1 standard deviation and over 4% of the global land area was subject to positive anomalies exceeding 2 standard deviations. Positive LSTmax anomalies display complex spatial patterns associated with heat waves and droughts across the global land area. The findings presented herein show that entire biomes are experiencing shifts in their LSTmax distributions driven by extreme climatic events and large-scale land surface changes, such as melting of ice sheets, severe droughts, and the incremental effects of forest loss in tropical forests. As climate warming and land-cover changes continue, it is likely that Earth’s maximum surface temperatures will experience greater and more frequent directional shifts, increasing the possibility that critical thresholds in Earth’s ecosystems and climate system will be surpassed, resulting in profound and irreversible changes

Improved upper limits on the flavor-changing neutral current decays B -> Kl(+)l(-) and B -> K*(892)l(+)l(-)

We have searched a sample of 9.6 x 10(6) B(B) over bar events for the flavor-changing neutral current decays B --> Kl(+)l(-) and B --> K*(892)l(+)l(-). We subject the latter decay to the requirement that the dilepton mass m(ll) exceed 0.5 GeV. There is no indication of a signal. We obtain the 90% confidence level upper limits B (B --> Kl(+)l(-)) K*(892)l(+)l(-))m(ll>0.5GeV) Kl(+)l(-)) + 0.35B(B --> K*(892)l(+)l(-))m(ll>0.5GeV) < 1.5 x 10(-6). The weighted-average limit is only 50% above the standard model prediction

Evaluation of the Role of Candida albicans Agglutinin-Like Sequence (Als) Proteins in Human Oral Epithelial Cell Interactions

The fungus C. albicans uses adhesins to interact with human epithelial surfaces in the processes of colonization and pathogenesis. The C. albicans ALS (agglutinin-like sequence) gene family encodes eight large cell-surface glycoproteins (Als1-Als7 and Als9) that have adhesive function. This study utilized C. albicans Δals mutant strains to investigate the role of the Als family in oral epithelial cell adhesion and damage, cytokine induction and activation of a MAPK-based (MKP1/c-Fos) signaling pathway that discriminates between yeast and hyphae. Of the eight Δals mutants tested, only the Δals3 strain showed significant reductions in oral epithelial cell adhesion and damage, and cytokine production. High fungal:epithelial cell multiplicities of infection were able to rescue the cell damage and cytokine production phenotypes, demonstrating the importance of fungal burden in mucosal infections. Despite its adhesion, damage and cytokine induction phenotypes, the Δals3 strain induced MKP1 phosphorylation and c-Fos production to a similar extent as control cells. Our data demonstrate that Als3 is involved directly in epithelial adhesion but indirectly in cell damage and cytokine induction, and is not the factor targeted by oral epithelial cells to discriminate between the yeast and hyphal form of C. albicans

Search for charmless B -> VV decays

We have studied two-body charmless decays of the B meson into the final states rho(o) rho(o), K(*o)rho(o), (KK*o)-K-*o, K-*o(K) over bar (*o), K(*+)rho(o), K*+, (K)over bar>(*o), and K*+K*- using only decay modes with charged daughter particles. Using 9.7 x 10(6) B (B) over bar pairs collected with the CLEO detector, we place 90% confidence level upper limits on the branching fractions (1.4-14.1) x 10(-5), depending on final state and polarization

Hadronic mass moments in inclusive semileptonic B meson decays

We have measured the first and second moments of the hadronic mass-squared distribution in B --> X(c)l nu, for P-lepton > 1.5 GeV/c. We find (M-x(2) - (M) over bar (2)(D)) = 0.251 +/- 0.066 GeV2, ((M-X(2) - (M-X(2))(2)) = 0.576 +/- 0.170 GeV4, where (M) over bar (D) is the spin-averaged D meson mass. From that first moment and the first moment of the photon energy spectrum in b --> s gamma, we find the heavy quark effective theory parameter lambda (1) (in the modified minimal subtraction renormalization scheme, to order 1/M-B(3) and beta (o)alpha (2)(s)) to be -0.24 +/- 0.11 GeV2. Using these first moments and the B semileptonic width, and assuming parton-hadron duality, we obtain \V-cb\ = 0.0404 +/- 0.0013