48 research outputs found

    Heterodinuclear ruthenium(II)-cobalt(III) complexes as models for a new approach to selective cancer treatment

    Get PDF
    Heterodinuclear ruthenium(ii)-cobalt(iii) complexes have been prepared as part of investigations into a new approach to selective cancer treatment. A cobalt(iii) centre bearing amine ligands, which serve as models for cytotoxic nitrogen mustard ligands, is connected by a bridging ligand to a ruthenium(ii)-polypyridyl moiety. Upon excitation of the ruthenium centre by visible light, electron transfer to the cobalt(iii) centre results in reduction to cobalt(ii) and consequent release of its ligands. We have synthesised several such structures and demonstrated their ability to release ligands upon excitation of the ruthenium centre by visible light

    Incorporating connectivity into conservation planning for the optimal representation of multiple species and ecosystem services

    Get PDF
    Funding was provided by the Rainforest Trust foundation. Support was also provided by the Sabah Forest Department, Forest Research Centre, the South East Asia Rainforest Research Partnership, the U.N. Development Programme, the Universiti Malaysia Sabah (FRGS0414-STWN-1/2015), PACOS Trust, BC Initiative, the Natural Environment Research Council UK (grant NE/R009597/1), and the Universities of Aberdeen, Montana, and York. We are grateful to the numerous researchers that collected the data used in our analyses, as well as the local communities and government staff who manage forested areas across Sabah.Peer reviewedPostprin

    The Palestinian primary ciliary dyskinesia population: first results of the diagnostic, and genetic spectrum

    Get PDF
    BACKGROUND: Diagnostic testing for primary ciliary dyskinesia (PCD) started in 2013 in Palestine. We aimed to describe the diagnostic, genetic and clinical spectrum of the Palestinian PCD population. METHODS: Individuals with symptoms suggestive of PCD were opportunistically considered for diagnostic testing: nasal nitric oxide (nNO) measurement, transmission electron microscopy (TEM) and/or PCD genetic panel or whole-exome testing. Clinical characteristics of those with a positive diagnosis were collected close to testing including forced expiratory volume in 1 s (FEV1) Global Lung Index z-scores and body mass index z-scores. RESULTS: 68 individuals had a definite positive PCD diagnosis, 31 confirmed by genetic and TEM results, 23 by TEM results alone, and 14 by genetic variants alone. 45 individuals from 40 families had 17 clinically actionable variants and four had variants of unknown significance in 14 PCD genes. CCDC39, DNAH11 and DNAAF11 were the most commonly mutated genes. 100% of variants were homozygous. Patients had a median age of 10.0 years at diagnosis, were highly consanguineous (93%) and 100% were of Arabic descent. Clinical features included persistent wet cough (99%), neonatal respiratory distress (84%) and situs inversus (43%). Lung function at diagnosis was already impaired (FEV1 z-score median −1.90 (−5.0–1.32)) and growth was mostly within the normal range (z-score mean −0.36 (−3.03–2.57). 19% individuals had finger clubbing. CONCLUSIONS: Despite limited local resources in Palestine, detailed geno- and phenotyping forms the basis of one of the largest national PCD populations globally. There was notable familial homozygosity within the context of significant population heterogeneity

    Culture and the Gender Gap in Competitive Inclination: Evidence from the Communist Experiment in China

    Full text link

    The National Early Warning Score and its subcomponents recorded within ±24 hours of emergency medical admission are poor predictors of hospital-acquired acute kidney injury

    Get PDF
    YesBackground: Hospital-acquired Acute Kidney Injury (H-AKI) is a common cause of avoidable morbidity and mortality. Aim: To determine if the patients’ vital signs data as defined by a National Early Warning Score (NEWS), can predict H-AKI following emergency admission to hospital. Methods: Analyses of emergency admissions to York hospital over 24-months with NEWS data. We report the area under the curve (AUC) for logistic regression models that used the index NEWS (model A0), plus age and sex (A1), plus subcomponents of NEWS (A2) and two-way interactions (A3). Likewise for maximum NEWS (models B0,B1,B2,B3). Results: 4.05% (1361/33608) of emergency admissions had H-AKI. Models using the index NEWS had the lower AUCs (0.59 to 0.68) than models using the maximum NEWS AUCs (0.75 to 0.77). The maximum NEWS model (B3) was more sensitivity than the index NEWS model (A0) (67.60% vs 19.84%) but identified twice as many cases as being at risk of H-AKI (9581 vs 4099) at a NEWS of 5. Conclusions: The index NEWS is a poor predictor of H-AKI. The maximum NEWS is a better predictor but seems unfeasible because it is only knowable in retrospect and is associated with a substantial increase in workload albeit with improved sensitivity.The Health Foundatio

    Thresholds for adding degraded tropical forest to the conservation estate

    Get PDF
    Logged and disturbed forests are often viewed as degraded and depauperate environments compared with primary forest. However, they are dynamic ecosystems1 that provide refugia for large amounts of biodiversity2,3, so we cannot afford to underestimate their conservation value4. Here we present empirically defined thresholds for categorizing the conservation value of logged forests, using one of the most comprehensive assessments of taxon responses to habitat degradation in any tropical forest environment. We analysed the impact of logging intensity on the individual occurrence patterns of 1,681 taxa belonging to 86 taxonomic orders and 126 functional groups in Sabah, Malaysia. Our results demonstrate the existence of two conservation-relevant thresholds. First, lightly logged forests (68%) of their biomass removed, and these are likely to require more expensive measures to recover their biodiversity value. Overall, our data confirm that primary forests are irreplaceable5, but they also reinforce the message that logged forests retain considerable conservation value that should not be overlooked

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

    Get PDF
    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    Recent developments in hydrogen evolving molecular cobalt(II)–polypyridyl catalysts

    No full text
    International audienceThe search for efficient noble metal-free hydrogen-evolving catalysts is the subject of intense research activity. A new family of molecular cobalt(II)–polypyridyl catalysts has recently emerged. These catalysts prove more robust under reductive conditions than other cobalt-based systems and display high activities under fully aqueous conditions. This review discusses the design, characterization, and evaluation of these catalysts for electrocatalytic and light-driven hydrogen production. Mechanistic considerations are addressed and structure–catalytic activity relationships identified in order to guide the future design of more efficient catalytic systems

    A simple method for the preparation of bio-inspired nickel bisdiphosphine hydrogen-evolving catalysts

    No full text
    International audienceWe herein report on a novel, simple and straightforward method for the preparation of nickel bisdiphosphine hydrogen-evolving catalysts, so-called DuBois catalysts, from commercially available nickel hexaaqua salts. This method yields coordination complexes with the same physical characteristics as previously described for compounds prepared from the [Ni(CH3_3CN)6_6]2+^{2+} precursor. However, if hexaaquanickel(II) chloride is used as a precursor, a different nickel bisdiphosphine complex is formed, which incorporates chloride as an axial ligand. This complex displays a significantly different electrochemical behavior and a diminished activity for proton reduction as compared to classic DuBois catalysts

    Bio-inspired noble metal-free nanomaterials approaching platinum performances for H2 evolution and uptake

    No full text
    International audienceHydrogen/water interconversion is a key reaction in the context of new energy technologies, including hydrogen fuel cells, water electrolyzers, and water-splitting photoelectrochemical cells. Specifications differ for these technologies to meet economic viability but state-of-the-art prototypes all rely on the powerful catalytic properties of the platinum metal as a catalyst for hydrogen production and uptake. Yet, this scarce and expensive metal is not itself a sustainable resource and its replacement by low cost and readily available materials is a requisite for these technologies to become economically viable. Here we revisit the preparation of bioinspired nanomaterials for hydrogen evolution and uptake (Le Goff et al., Science, 2009, 326, 1384–1387) and show that molecular engineering combined with three dimensional structuring of the electrode material allows the preparation of stable materials based on nickel bisdiphosphine catalytic units with performances in a 0.5 M sulphuric acid aqueous electrolyte that approach those of commercial platinum-based materials (0.05 mgPt cm−2) assessed under similar, technologically relevant, operational conditions
    corecore