86 research outputs found

    Dipole-field-assisted charge extraction in metal-perovskite-metal back-contact solar cells

    Full text link
    Hybrid organic-inorganic halide perovskites are low-cost solution-processable solar cell materials with photovoltaic properties that rival those of crystalline silicon. The perovskite films are typically sandwiched between thin layers of hole and electron transport materials, which efficiently extract photogenerated charges. This affords high-energy conversion efficiencies but results in significant performance and fabrication challenges. Herein we present a simple charge transport layer-free perovskite solar cell (PSC), comprising only a perovskite layer with two interdigitated gold back-contacts. Charge extraction is achieved via self-assembled molecular monolayers (SAMs) and their associated dipole fields at the metal/perovskite interface. Photovoltages of approximately 600 mV generated by SAM-modified PSCs are equivalent to the built-in potential generated by individual dipole layers. Efficient charge extraction results in photocurrents of up to 12.1 mA/cm2 under simulated sunlight, despite a large electrode spacing.Comment: 18 pages, 5 figure

    Determining the date of diagnosis – is it a simple matter? The impact of different approaches to dating diagnosis on estimates of delayed care for ovarian cancer in UK primary care

    Get PDF
    Background Studies of cancer incidence and early management will increasingly draw on routine electronic patient records. However, data may be incomplete or inaccurate. We developed a generalisable strategy for investigating presenting symptoms and delays in diagnosis using ovarian cancer as an example. Methods The General Practice Research Database was used to investigate the time between first report of symptom and diagnosis of 344 women diagnosed with ovarian cancer between 01/06/2002 and 31/05/2008. Effects of possible inaccuracies in dating of diagnosis on the frequencies and timing of the most commonly reported symptoms were investigated using four increasingly inclusive definitions of first diagnosis/suspicion: 1. "Definite diagnosis" 2. "Ambiguous diagnosis" 3. "First treatment or complication suggesting pre-existing diagnosis", 4 "First relevant test or referral". Results The most commonly coded symptoms before a definite diagnosis of ovarian cancer, were abdominal pain (41%), urogenital problems(25%), abdominal distension (24%), constipation/change in bowel habits (23%) with 70% of cases reporting at least one of these. The median time between first reporting each of these symptoms and diagnosis was 13, 21, 9.5 and 8.5 weeks respectively. 19% had a code for definitions 2 or 3 prior to definite diagnosis and 73% a code for 4. However, the proportion with symptoms and the delays were similar for all four definitions except 4, where the median delay was 8, 8, 3, 10 and 0 weeks respectively. Conclusion Symptoms recorded in the General Practice Research Database are similar to those reported in the literature, although their frequency is lower than in studies based on self-report. Generalisable strategies for exploring the impact of recording practice on date of diagnosis in electronic patient records are recommended, and studies which date diagnoses in GP records need to present sensitivity analyses based on investigation, referral and diagnosis data. Free text information may be essential in obtaining accurate estimates of incidence, and for accurate dating of diagnoses

    Current knowledge, status and future for plant and fungal diversity in Great Britain and the UK Overseas Territories

    Get PDF
    Societal Impact Statement We rely on plants and fungi for most aspects of our lives. Yet plants and fungi are under threat, and we risk losing species before we know their identity, roles, and potential uses. Knowing names, distributions, and threats are first steps toward effective conservation action. Accessible products like field guides and online resources engage society, harnessing collective support for conservation. Here, we review current knowledge of the plants and fungi of the UK and UK Overseas Territories, highlighting gaps to help direct future research efforts toward conserving these vital elements of biodiversity. Summary This review summarizes current knowledge of the status and threats to the plants and fungi of Great Britain and the UK Overseas Territories (UKOTs). Although the body of knowledge is considerable, the distribution of information varies substantially, and we highlight knowledge gaps. The UK vascular flora is the most well studied and we have a relatively clear picture of its 9,001 native and alien taxa. We have seedbanked 72% of the native and archaeophyte angiosperm taxa and 78% of threatened taxa. Knowledge of the UKOTs flora varies across territories and we report a UKOTs flora comprising 4,093 native and alien taxa. We have conserved 27% of the native flora and 51% of the threatened vascular plants in Kew's Millennium Seed Bank, UK. We need a better understanding of the conservation status of plants in the wild, and progress toward completion or updating national red lists varies. Site‐based protection of key plant assemblages is outlined, and progress in identifying Important Plant Areas analyzed. Knowledge of the non‐vascular flora, especially seaweeds remains patchy, particularly in many UKOTs. The biggest gaps overall are in fungi, particularly non‐lichenized fungi. Considerable investment is needed to fill these knowledge gaps and instigate effective conservation strategies

    COVID-19: Third dose booster vaccine effectiveness against breakthrough coronavirus infection, hospitalisations and death in patients with cancer: A population-based study

    Get PDF
    Purpose: People living with cancer and haematological malignancies are at increased risk of hospitalisation and death following infection with acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Coronavirus third dose vaccine boosters are proposed to boost waning immune responses in immunocompromised individuals and increase coronavirus protection; however, their effectiveness has not yet been systematically evaluated. Methods: This study is a population-scale real-world evaluation of the United Kingdom’s third dose vaccine booster programme for cancer patients from 8th December 2020 to 7th December 2021. The cancer cohort comprises individuals from Public Health England’s national cancer dataset, excluding individuals less than 18 years. A test-negative case-control design was used to assess third dose booster vaccine effectiveness. Multivariable logistic regression models were fitted to compare risk in the cancer cohort relative to the general population. Results: The cancer cohort comprised of 2,258,553 tests from 361,098 individuals. Third dose boosters were evaluated by reference to 87,039,743 polymerase chain reaction (PCR) coronavirus tests. Vaccine effectiveness against breakthrough infections, symptomatic infections, coronavirus hospitalisation and death in cancer patients were 59.1%, 62.8%, 80.5% and 94.5% respectively. Lower vaccine effectiveness was associated with a cancer diagnosis within 12 months, lymphoma, recent systemic anti-cancer therapy (SACT) or radiotherapy. Lymphoma patients had low levels of protection from symptomatic disease. In spite of third dose boosters, following multivariable adjustment, individuals with cancer remain at increased risk of coronavirus hospitalisation and death compared to the population control (OR 3.38, 3.01 respectively. p<0.001 for both). Conclusions: Third dose boosters are effective for most individuals with cancer, increasing protection from coronavirus. However, their effectiveness is heterogenous, and lower than the general population. Many patients with cancer will remain at increased risk of coronavirus infections, even after 3 doses. In the case of patients with lymphoma, there is a particularly strong disparity of vaccine effectiveness against breakthrough infection and severe disease. Breakthrough infections will disrupt cancer care and treatment with potentially adverse consequences on survival outcomes. The data support the role of vaccine boosters in preventing severe disease, and further pharmacological intervention to prevent transmission and aid viral clearance to limit disruption of cancer care as the delivery of care continues to evolve during the coronavirus pandemic

    Marketing as a means to transformative social conflict resolution: lessons from transitioning war economies and the Colombian coffee marketing system

    Get PDF
    Social conflicts are ubiquitous to the human condition and occur throughout markets, marketing processes, and marketing systems.When unchecked or unmitigated, social conflict can have devastating consequences for consumers, marketers, and societies, especially when conflict escalates to war. In this article, the authors offer a systemic analysis of the Colombian war economy, with its conflicted shadow and coping markets, to show how a growing network of fair-trade coffee actors has played a key role in transitioning the country’s war economy into a peace economy. They particularly draw attention to the sources of conflict in this market and highlight four transition mechanisms — i.e., empowerment, communication, community building and regulation — through which marketers can contribute to peacemaking and thus produce mutually beneficial outcomes for consumers and society. The article concludes with a discussion of implications for marketing theory, practice, and public policy

    Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

    Get PDF
    BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

    New loci for body fat percentage reveal link between adiposity and cardiometabolic disease risk

    Get PDF
    To increase our understanding of the genetic basis of adiposity and its links to cardiometabolic disease risk, we conducted a genome-wide association meta-analysis of body fat percentage (BF%) in up to 100,716 individuals. Twelve loci reached genome-wide significance (P<5 × 10−8), of which eight were previously associated with increased overall adiposity (BMI, BF%) and four (in or near COBLL1/GRB14, IGF2BP1, PLA2G6, CRTC1) were novel associations with BF%. Seven loci showed a larger effect on BF% than on BMI, suggestive of a primary association with adiposity, while five loci showed larger effects on BMI than on BF%, suggesting association with both fat and lean mass. In particular, the loci more strongly associated with BF% showed distinct cross-phenotype association signatures with a range of cardiometabolic traits revealing new insights in the link between adiposity and disease risk

    Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans

    Get PDF
    Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in 25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16 regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP, while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium (LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region. Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa, an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent signals within the same regio

    Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

    Get PDF
    Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p&lt;0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p&lt;0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised
    corecore