Numerical study of the thermoelectric power factor in ultra-thin Si nanowires

Low dimensional structures have demonstrated improved thermoelectric (TE) performance because of a drastic reduction in their thermal conductivity, {\kappa}l. This has been observed for a variety of materials, even for traditionally poor thermoelectrics such as silicon. Other than the reduction in {\kappa}l, further improvements in the TE figure of merit ZT could potentially originate from the thermoelectric power factor. In this work, we couple the ballistic (Landauer) and diffusive linearized Boltzmann electron transport theory to the atomistic sp3d5s*-spin-orbit-coupled tight-binding (TB) electronic structure model. We calculate the room temperature electrical conductivity, Seebeck coefficient, and power factor of narrow 1D Si nanowires (NWs). We describe the numerical formulation of coupling TB to those transport formalisms, the approximations involved, and explain the differences in the conclusions obtained from each model. We investigate the effects of cross section size, transport orientation and confinement orientation, and the influence of the different scattering mechanisms. We show that such methodology can provide robust results for structures including thousands of atoms in the simulation domain and extending to length scales beyond 10nm, and point towards insightful design directions using the length scale and geometry as a design degree of freedom. We find that the effect of low dimensionality on the thermoelectric power factor of Si NWs can be observed at diameters below ~7nm, and that quantum confinement and different transport orientations offer the possibility for power factor optimization.Comment: 42 pages, 14 figures; Journal of Computational Electronics, 201

INTEGRATE II: randomised phase III controlled trials of regorafenib containing regimens versus standard of care in refractory Advanced Gastro-Oesophageal Cancer (AGOC): a study by the Australasian Gastro-Intestinal Trials Group (AGITG)

BACKGROUND: Advanced gastro-oesophageal cancer (AGOC) carries a poor prognosis. No standard of care treatment options are available after first and second-line therapies. Regorafenib is an oral multi-targeted tyrosine kinase inhibitor targeting angiogenic, stromal, and oncogenic receptor tyrosine kinases. Regorafenib 160 mg daily prolonged progression free survival compared to placebo (INTEGRATE, phase 2). Regorafenib 80 mg daily in combination with nivolumab 3 mg/kg showed promising objective response rates (REGONIVO). METHODS/DESIGN: INTEGRATE II (INTEGRATE IIa and IIb) platform comprises two international phase III randomised controlled trials (RCT) with 2:1 randomisation in favor of experimental intervention. INTEGRATE IIa (double-blind) compares regorafenib 160 mg daily on days 1 to 21 of each 28-day cycle to placebo. INTEGRATE IIb (open label) compares REGONIVO, regorafenib 90 mg days 1 to 21 in combination with intravenous nivolumab 240 mg days 1 and 15 each 28-day cycle with investigator's choice of chemotherapy (control). Treatment continues until disease progression or intolerable adverse events as per protocol. Eligible participants include adults with AGOC who have failed two or more lines of treatment. Stratification is by location of tumour (INTEGRATE IIa only), geographic region, prior VEGF inhibitor and prior immunotherapy use (INTEGRATE IIb only). Primary endpoint is overall survival. Secondary endpoints are progression free survival, objective response rate, quality of life, and safety. Tertiary/correlative objectives include biomarker and pharmacokinetic evaluation. DISCUSSION: INTEGRATE II provides a platform to evaluate the clinical utility of regorafenib alone, as well as regorafenib in combination with nivolumab in treatment of participants with refractory AGOC. TRIAL REGISTRATION: INTEGRATE IIa prospectively registered 1 April 2016 Australia New Zealand Clinical Trial Registry: ACTRN12616000420448 (ClinicalTrials.gov NCT02773524). INTEGRATE IIb prospectively registered 10 May 2021 ClinicalTrials.gov: NCT04879368.Lyn Ley Lam, Nick Pavlakis, Kohei Shitara, Katrin M. Sjoquist, Andrew J. Martin, Sonia Yip, Yoon, Koo Kang, Yung, Jue Bang, Li, Tzong Chen, Markus Moehler, Tanios Bekaii, Saab, Thierry Alcindor, Christopher J. O, Callaghan, Niall C. Tebbutt, Wendy Hague, Howard Chan, Sun Young Rha, Keun, Wook Lee, Val Gebski, Anthony Jaworski, John Zalcberg, Timothy Price, John Simes, and David Goldstei

Dynamics of control in construction project teams

Control is pervasive in construction project environments. The management of projects through various planning and control tools has therefore been described essentially as rebureaucratization which increases control over individuals, teams and organizations through ideologies of efficiency and performativity. Yet certain characteristics of the project setting make it an ideal climate for the empowerment of individuals and teams. The manifestations of control in five construction project management teams involved in two ongoing construction projects in Hong Kong are examined. The interpretive and exploratory focus of the study favoured the use of a qualitative research design and the case study approach in particular. Control is viewed as all devices and systems employed to ensure that acts, behaviours, outcomes and decisions of individuals, teams and organizations are consistent with meeting organizational or project goals, objectives and strategies. The findings indicate that a portfolio of control modes is implemented in project teams comprising both formal (i.e. behaviour‐ and outcome‐based) and informal (i.e. clan‐ and self‐based) control mechanisms which are not necessarily incompatible. While formal control remains the primary control mode, a portfolio of control appears necessary to augment the inadequacies of formal control due to the evolving nature of the project environment.Empowerment, formal control, Hong Kong, informal control, portfolio of control,