Publications by authors named "Shaun Tan"

We used epidemiological data from 21195 patients with cancer and 180407 matched controls, including in-depth analyses in 216 cancer patients, to discover clinical and molecular determinants that predispose cancer patients to breakthrough infections. Patients with B cell malignancies, with differential expression of CD24, CDK14 and PLEKHG1, were most susceptible to breakthrough infections, suggesting that these patients may require more booster immunisations to ameliorate cellular responses and immune protection against COVID-19.

View Article and Find Full Text PDF

The two-dimensional on three-dimensional (2D/3D) perovskite bilayer heterostructure can improve the stability and performance of perovskite solar cells. We show that the 2D/3D perovskite stack in a device evolves dynamically during its end-of-life decomposition. Initially phase-pure 2D interlayers can evolve differently, resulting in different device stabilities.

View Article and Find Full Text PDF

A novel A-D-A type small molecule (DTP-2EH-IO2Cl) incorporating dithiophenepyrrole (DTP) core with indene-dione (IO2Cl) side chain with an intermediate band gap and rigid structure is incorporated into polymer donor PM6 and one of the three A-DA'D-A small molecule acceptor-L8-BO, BTP-eC9 or Y6-for ternary-blend organic photovoltaics (OPVs). The third component DTP-2EH-IO2Cl induces not only energy transfer but also stronger molecular packing of the acceptors, resulting in a larger coherence length and enhanced absorption that enhances devices' power conversion efficiencies (PCE) and thermal stability. The PCE values of the champion ternary-blend devices PM6:L8-BO, PM6:BTP-eC9, and PM6:Y6 incorporating DTP-2EH-IO2Cl are 19.

View Article and Find Full Text PDF

Interface engineering plays a critical role in advancing the performance of perovskite solar cells. As such, 2D/3D perovskite heterostructures are of particular interest due to their optoelectrical properties and their further potential improvements. However, for conventional solution-processed 2D perovskites grown on an underlying 3D perovskite, the reaction stoichiometry is normally unbalanced with excess precursors.

View Article and Find Full Text PDF

Preventing ion migration in perovskite photovoltaics is key to achieving stable and efficient devices. The activation energy for ion migration is affected by the chemical environment surrounding the ions. Thus, the migration of organic cations in lead halide perovskites can be mitigated by engineering their local interactions, for example through hydrogen bonding.

View Article and Find Full Text PDF

In pursuing high stability and power conversion efficiency for organic photovoltaics (OPVs), a sequential deposition (SD) approach to fabricate active layers with p-i-n structures (where p, i, and n represent the electron donor, mixed donor:acceptor, and electron acceptor regions, respectively, distinctively different from the bulk heterojunction (BHJ) structure) has emerged. Here, we present a novel approach that by incorporating two polymer donors, and , and one small-molecule acceptor, , into the active layer with sequential deposition, we formed a device with nanometer-scale twin p-i-n structured active layer. The twin p-i-n device involved first depositing a blend under layer and then a top layer and exhibited an improved power conversion efficiency (PCE) value of 18.

View Article and Find Full Text PDF

Perovskite photovoltaics, typically based on a solution-processed perovskite layer with a film thickness of a few hundred nanometres, have emerged as a leading thin-film photovoltaic technology. Nevertheless, many critical issues pose challenges to its commercialization progress, including industrial compatibility, stability, scalability and reliability. A thicker perovskite film on a scale of micrometres could mitigate these issues.

View Article and Find Full Text PDF

Metal halide perovskite solar cells (PSCs) are infamous for their batch-to-batch and lab-to-lab irreproducibility in terms of stability and performance. Reproducible fabrication of PSCs is a critical requirement for market viability and practical commercialization. PSC irreproducibility plagues all levels of the community; from institutional research laboratories, start-up companies, to large established corporations.

View Article and Find Full Text PDF
Article Synopsis
  • * The blend of Y6-IO2F with P3HT achieved optimal morphology leading to a high power conversion efficiency (PCE) of 10.5% and short-circuit current density of 15.9 mA/cm², outperforming others like P3HT:Y1-IO2F which had a PCE of only 2.2%.
View Article and Find Full Text PDF

Chemical bath deposition (CBD) is widely used to deposit tin oxide (SnO ) as an electron-transport layer in perovskite solar cells (PSCs). The conventional recipe uses thioglycolic acid (TGA) to facilitate attachments of SnO particles onto the substrate. However, nonvolatile TGA is reported to harm the operational stability of PSCs.

View Article and Find Full Text PDF

The black phase of formamidinium lead iodide (FAPbI) perovskite shows huge promise as an efficient photovoltaic, but it is not favoured energetically at room temperature, meaning that the undesirable yellow phases are always present alongside it during crystallization. This problem has made it difficult to formulate the fast crystallization process of perovskite and develop guidelines governing the formation of black-phase FAPbI (refs. ).

View Article and Find Full Text PDF

Background: Due to aging of the global population, hepatocellular carcinoma (HCC) is increasingly common among elderly patients, but outcomes after curative hepatic resection are unclear. Using a metanalytic approach, we aimed to estimate overall survival (OS), recurrence-free survival (RFS), and complication rates in elderly HCC patients undergoing resection.

Methods: We searched PubMed, Embase, and Cochrane databases from inception to November 10, 2020, for studies reporting outcomes in elderly (age ≥65 years) patients with HCC undergoing curative surgical resection.

View Article and Find Full Text PDF

Purpose: The COVID-19 pandemic has drastically disrupted global healthcare systems. With the higher demand for healthcare and misinformation related to COVID-19, there is a need to explore alternative models to improve communication. Artificial Intelligence (AI) and Natural Language Processing (NLP) have emerged as promising solutions to improve healthcare delivery.

View Article and Find Full Text PDF
Article Synopsis
  • Three doses of SARS-CoV-2 mRNA vaccines are recommended for cancer patients to decrease severe disease risk, especially given that ongoing anti-cancer treatments can impact vaccine effectiveness.
  • Researchers evaluated 273 cancer patients (both solid and blood cancers) between July 2021 and March 2022, measuring immune responses after each vaccine dose.
  • The study found that while seroconversion rates improved with each dose (35.2% after 1 dose, 79.4% after 2 doses, and 92.4% after 3 doses), patients on active treatment for blood cancers had significantly lower antibody levels compared to those on immunotherapy and chemotherapy.
View Article and Find Full Text PDF

Purpose: To study the effect of implant angulation on 3D linear and absolute angular distortions of implant analogs in printed resin models and conventional stone casts.

Materials And Methods: Three sectional master models with two implants with total inter-implant angulations of 0°, 10°, and 20° were fabricated. For each master model, five conventional stone casts (CS) and printed resin models (PM) were fabricated (n = 5).

View Article and Find Full Text PDF

Cations with suitable sizes to occupy an interstitial site of perovskite crystals have been widely used to inhibit ion migration and promote the performance and stability of perovskite optoelectronics. However, such interstitial doping inevitably leads to lattice microstrain that impairs the long-range ordering and stability of the crystals, causing a sacrificial trade-off. Here, we unravel the evident influence of the valence states of the interstitial cations on their efficacy to suppress the ion migration.

View Article and Find Full Text PDF

Objectives: COVID-19 infection is associated with significant morbidity in systemic lupus erythematosus but is potentially preventable by vaccination, although the impact of the myriad vaccines among SLE patients is not established. We aimed to assess the effectiveness, efficacy, acceptance and safety of COVID-19 vaccination in SLE.

Methods: We performed a systematic review of PubMed, EMBASE, CENTRAL, and Scopus publications until 8 June 2022 without language, publication year or publication status restrictions.

View Article and Find Full Text PDF

Background: Direct oral anticoagulants (DOACs) have been increasingly used as anticoagulation therapy in the postoperative period. However, their effectiveness in post-cardiac surgical atrial fibrillation is yet to be determined.

Methods: We conducted a meta-analysis, searching three international databases from 1 January 2003 to 26 January 2022 for studies reporting on DOACs in at least 10 adult patients (>18 yr of age) with post-cardiac surgical atrial fibrillation.

View Article and Find Full Text PDF

Background: New-graduate physiotherapists experience a steep learning curve when transitioning from student to clinician. The acute hospital setting is known to present unique challenges for health clinicians, however, the preparedness of new-graduate physiotherapists for working within this setting remains unclear.

Purpose: The aim of this study was to investigate new-graduate physiotherapists' experiences of working in acute hospital settings and their perceptions toward how their pre-professional training prepared them for this setting.

View Article and Find Full Text PDF

Optoelectronic devices consist of heterointerfaces formed between dissimilar semiconducting materials. The relative energy-level alignment between contacting semiconductors determinately affects the heterointerface charge injection and extraction dynamics. For perovskite solar cells (PSCs), the heterointerface between the top perovskite surface and a charge-transporting material is often treated for defect passivation to improve the PSC stability and performance.

View Article and Find Full Text PDF

The A cation in ABX organic-inorganic lead halide perovskites (OLHPs) was conventionally believed to hardly affect their optoelectronic properties. However, more recent developments have unraveled the critical role of the A cation in the regulation of the physicochemical and optoelectronic properties of OLHPs. We review the important breakthroughs enabled by the versatility of the A cation and highlight potential opportunities and unanswered questions related to the A cation in OLHPs.

View Article and Find Full Text PDF

Coronavirus Disease 2019 (COVID-19) serology has an evolving role in the diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, its use in hospitalized patients with acute respiratory symptoms remains unclear. Hospitalized patients with acute respiratory illness admitted to an isolation ward were recruited.

View Article and Find Full Text PDF
Article Synopsis
  • Semitransparent organic photovoltaics (OPVs) show promise for use in building-integrated applications like energy-generating greenhouses, but achieving both high visible transmittance and power conversion efficiency has been challenging for commercialization.
  • A key issue is that replacing opaque electrodes with semitransparent ones typically reduces charge carrier extraction efficiency.
  • The introduction of a dual-function interlayer improves the interface between the hole-transport layer and the semitransparent electrode, resulting in better charge extraction, increased light transmittance in the 400-450 nm range, a power conversion efficiency of 13.7%, and an average visible transmittance of 22.2%.
View Article and Find Full Text PDF

The COVID-19 pandemic has had an unprecedented impact on healthcare systems globally, giving rise to significant morbidity and mortality. Vaccination has been widely regarded as the most important strategy to contain the pandemic. Whilst local side-effects of the BNT-162b2 (Pfizer-BioNTech) vaccine are well known, concern has emerged due to sporadic reports of immune-mediated adverse effects (Cines and Bussel, 2021; Rela et al.

View Article and Find Full Text PDF

Superior bandgap tunability enables solution-processed halide perovskite a promising candidate for multi-junction photovoltaics (PVs). Particularly, optically coupling wide-gap perovskite by stacking with commercially available PVs such as silicon and CIGS (also known as 4-terminal tandem) simplifies the technology transfer process, and further advances the commercialization potential of perovskite technology. However, compared with matured PV materials and the phase-pure FAPbI , wide-gap perovskite still suffers from huge voltage deficits.

View Article and Find Full Text PDF