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[This corrects the article DOI: 10.1371/journal.pone.0061852.].
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The Covid-19 pandemic has laid bare a tension around scientific expertise that has major implications for the effectiveness of health systems. Critical engagement with this tension, however, is largely missing from the lessons and programs consolidating in the wake of the emergency. Lacking good frameworks for discussing the tension, the vague term "public trust" has proliferated into a buzzword that stands in for more articulate discussion. The tension between experts and the public is not new, however. It is useful to look back to the 1930s, when health experts identifying as "new epidemiologists" imagined a new modern science of epidemiology that, some believed, would resolve evident failures in public cooperation. Historical analysis of different approaches to the production and use of epidemiological knowledge in these years reveals a debate about power at the heart of epidemiology, and a critical framework for discussing the tension around epidemiological expertise in public health.
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COVID-19 , Pandemias , Humanos , Saúde Pública , Epidemiologistas , ConfiançaRESUMO
Seafood mislabelling and species substitution, compounded by a convoluted seafood supply chain with significant traceability challenges, hinder efforts towards more sustainable, responsible, and ethical fishing and business practices. We conducted the largest evaluation of the quality and accuracy of labels for 672 seafood products sold in Australia, assessing six seafood groups (i.e., hoki, prawns, sharks and rays, snapper, squid and cuttlefish, and tuna) from fishmongers, restaurants, and supermarkets, including domestically caught and imported products. DNA barcoding revealed 11.8% of seafood tested did not match their label with sharks and rays, and snappers, having the highest mislabelling rate. Moreover, only 25.5% of products were labelled at a species-level, while most labels used vague common names or umbrella terms such as 'flake' and 'snapper'. These poor-quality labels had higher rates of mislabelling than species-specific labels and concealed the sale of threatened or overfished taxa, as well as products with lower nutritional quality, reduced economic value, or potential health risks. Our results highlight Australia's weak seafood labelling regulations and ambiguous non-mandatory naming conventions, which impede consumer choice for accurately represented, sustainable, and responsibly sourced seafood. We recommend strengthening labelling regulations to mitigate seafood mislabelling and substitution, ultimately improving consumer confidence when purchasing seafood.
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Rotulagem de Alimentos , Alimentos Marinhos , Comércio , Comportamento do Consumidor , AustráliaRESUMO
Widespread industrial use of per- and polyfluoroalkyl substances (PFAS) as surfactants has led to global contamination of water sources with these persistent, highly stable chemicals. As a result, humans and wildlife are regularly exposed to PFAS, which have been shown to bioaccumulate and cause adverse health effects. Methods for detecting PFAS in water are currently limited and primarily utilize mass spectrometry (MS), which is time-consuming and requires expensive instrumentation. Thus, new methods are needed to rapidly and reliably assess the pollution level of water sources. While some fluorescent PFAS sensors exist, they typically function in high nanomolar or micromolar concentration ranges and focus on sensing only 1-2 individual PFAS. Our work aims to address this problem by developing a fluorescent sensor for both individual PFAS, as well as complex PFAS mixtures, and demonstrate its functionality in tap water samples. Here we show that dynamic combinatorial libraries (DCLs) with simple building blocks can be templated with a fluorophore and subsequently used as sensors to form an array that differentially detects each PFAS species and various mixtures thereof. Our method is a high-throughput analysis technique that allows many samples to be analyzed simultaneously with a plate reader. This is one of the first examples of a fluorescent PFAS sensor array that functions at low nanomolar concentrations, and herein we report its use for the rapid detection of PFAS contamination in water.
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A warming climate coupled with reductions in water availability and rising salinity are increasingly affecting rice (Oryza sativa) yields. Elevated temperatures combined with vapour pressure deficit (VPD) rises are causing stomatal closure, further reducing plant productivity and cooling. It is unclear what stomatal size (SS) and stomatal density (SD) will best suit all these environmental extremes. To understand how stomatal differences contribute to rice abiotic stress resilience, we screened the stomatal characteristics of 72 traditionally bred varieties. We found significant variation in SS, SD and calculated anatomical maximal stomatal conductance (gsmax ) but did not identify any varieties with SD and gsmax as low as transgenic OsEPF1oe plants. Traditionally bred varieties with high SD and small SS (resulting in higher gsmax ) typically had lower biomasses, and these plants were more resilient to drought than low SD and large SS plants, which were physically larger. None of the varieties assessed were as resilient to drought or salinity as low SD OsEPF1oe transgenic plants. High SD and small SS rice displayed faster stomatal closure during increasing temperature and VPD, but photosynthesis and plant cooling were reduced. Compromises will be required when choosing rice SS and SD to tackle multiple future environmental stresses.
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Oryza , Estômatos de Plantas , Oryza/genética , Melhoramento Vegetal , Plantas Geneticamente Modificadas , Estresse Fisiológico , Secas , ÁguaRESUMO
Extracellular vesicles (EVs) are cell-derived nanoparticles that facilitate transport of proteins, lipids, and genetic material, playing important roles in intracellular communication. They have remarkable potential as non-toxic and non-immunogenic nanocarriers for drug delivery to unreachable organs and tissues, in particular, the central nervous system (CNS). Herein, we developed a novel platform based on macrophage-derived EVs to treat Parkinson disease (PD). Specifically, we evaluated the therapeutic potential of EVs secreted by autologous macrophages that were transfected ex vivo to express glial-cell-line-derived neurotrophic factor (GDNF). EV-GDNF were collected from conditioned media of GDNF-transfected macrophages and characterized for GDNF content, size, charge, and expression of EV-specific proteins. The data revealed that, along with the encoded neurotrophic factor, EVs released by pre-transfected macrophages carry GDNF-encoding DNA. Four-month-old transgenic Parkin Q311(X)A mice were treated with EV-GDNF via intranasal administration, and the effect of this therapeutic intervention on locomotor functions was assessed over a year. Significant improvements in mobility, increases in neuronal survival, and decreases in neuroinflammation were found in PD mice treated with EV-GDNF. No offsite toxicity caused by EV-GDNF administration was detected. Overall, an EV-based approach can provide a versatile and potent therapeutic intervention for PD.
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Vesículas Extracelulares , Doença de Parkinson , Animais , Sistema Nervoso Central , Vesículas Extracelulares/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Macrófagos/metabolismo , Camundongos , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Doença de Parkinson/terapiaRESUMO
Rice (Oryza sativa L.) is an important food crop relied upon by billions of people worldwide. However, with increasing pressure from climate change and rapid population growth, cultivation is very water-intensive. Therefore, it is critical to produce rice that is high-yielding and genetically more water-use efficient. Here, using the stabilized fast-neutron mutagenized population of Jao Hom Nin (JHN) - a popular purple rice cultivar - we microscopically examined hundreds of flag leaves to identify four stomatal model mutants with either high density (HD) or low density (LD) stomata, and small-sized (SS) or large-sized (LS) stomata. With similar genetic background and uniformity, the stomatal model mutants were used to understand the role of stomatal variants on physiological responses to abiotic stress. Our results show that SS and HD respond better to increasing CO2 concentration and HD has higher stomatal conductance (gs) compared to the other stomatal model mutants, although the effects on gas exchange or overall plant performance were small under greenhouse conditions. In addition, the results of our drought experiments suggest that LD and SS can better adapt to restricted water conditions, and LD showed higher water use efficiency (WUE) and biomass/plant than other stomatal model mutants under long-term restricted water treatment. Finally, our study suggests that reducing stomata density and size may play a promising role for further work on developing a climate-ready rice variety to adapt to drought and heat stress. We propose that low stomata density and small size have high potential as genetic donors for improving WUE in climate-ready rice.
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Trimethylamine N-oxide (TMAO) is produced in the gut via metabolism of dietary betaine, choline, and carnitine, and elevated TMAO in plasma is associated with adverse health effects, including cardiovascular events. Currently, we lack high throughput methods for sensing these metabolites and detecting high TMAO. Thus, we have adapted our previously described "imprint-and-report" fluorescent sensing method using dynamic combinatorial libraries (DCLs) to create a sensor array for these four metabolites that functions at physiologically relevant concentrations. Templation of DCLs with dye and subsequent addition of analytes generates a fluorescent fingerprint for each metabolite and allows for differentiation via principal component analysis (PCA). Furthermore, we demonstrate that this system can be used to characterize mixtures of the metabolites in both buffer and human plasma samples. Using three to six DCLs, we can distinguish between plasma samples with healthy and elevated levels of TMAO.
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Betaína , Metilaminas , Betaína/metabolismo , Colina , Misturas Complexas , HumanosRESUMO
Metastatic non-small cell lung cancer (NSCLC) remains largely incurable and the prognosis is extremely poor once it spreads to the brain. In particular, in patients with brain metastases, the blood brain barrier (BBB) remains a significant obstacle for the biodistribution of antitumor drugs and immune cells. Here we report that chimeric antigen receptor (CAR) T cells targeting B7-H3 (B7-H3.CAR) exhibit antitumor activity in vitro against tumor cell lines and lung cancer organoids, and in vivo in xenotransplant models of orthotopic and metastatic NSCLC. The co-expression of the CCL2 receptor CCR2b in B7-H3.CAR-T cells, significantly improves their capability of passing the BBB, providing enhanced antitumor activity against brain tumor lesions. These findings indicate that leveraging T-cell chemotaxis through CCR2b co-expression represents a strategy to improve the efficacy of adoptive T-cell therapies in patients with solid tumors presenting with brain metastases.
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Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Receptores de Antígenos Quiméricos , Encéfalo/metabolismo , Neoplasias Encefálicas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Movimento Celular , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Linfócitos T , Distribuição Tecidual , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
CONTEXT: As of 2015, an estimated 116000 New York City (NYC) residents had chronic hepatitis C, many of them undiagnosed. Although effective medications have been available since 2014 with the advent of direct-acting antivirals, provider-based barriers to treatment remain. The NYC Department of Health and Mental Hygiene (Health Department) coordinated the Hepatitis C Clinical Exchange Network (HepCX) from 2015 to 2019. The main goal of HepCX was to promote hepatitis C screening and treatment by hospital-based providers. PROGRAM: The Health Department recruited hepatitis C champions (Champions) from acute care hospitals (n = 40) to promote improved hepatitis C care at their institutions. The Health Department provided technical assistance for hospitals to improve electronic medical record (EMR) systems and implement reflex RNA testing, coordinated trainings to increase capacity to treat hepatitis C, and distributed dashboards containing facility-specific testing and treatment metrics. IMPLEMENTATION: By the end of the project period (2019), most hospitals (36/40; 90%) reported having a screening alert for baby boomers in their EMR system and 34 (85%) reported performing reflex RNA testing after a positive hepatitis C antibody test. The Health Department coordinated opportunities for Champions to share their work with providers from network hospitals at meetings and webinars and provided clinical education on hepatitis C treatment in partnership with a local nonprofit organization focused on liver health. Facility-specific dashboards were distributed annually to hospital leadership. RNA confirmation testing increased from an average of 57% in 2015 to 85% in 2018. Treatment initiation rates remained similar over 2 years, averaging 39% in 2017 and 38% in 2018. DISCUSSION: HepCX was a multipronged initiative designed to promote hepatitis C testing and treatment initiation among providers at NYC acute care hospitals. Improvements were observed in confirmatory testing rates; however, treatment initiation rates did not change. Further efforts should be targeted to hospitals in need of additional resources for linkage to care and treatment of hepatitis C.
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Hepatite C Crônica , Hepatite C , Antivirais/uso terapêutico , Hepacivirus , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Hospitais , Humanos , Programas de RastreamentoRESUMO
Sensor arrays using synthetic receptors have found great utility in analyte detection, resulting from their ability to distinguish analytes based on differential signals via indicator displacement. However, synthesis and characterization of receptors for an array remain a bottleneck in the field. Receptor discovery has been streamlined using dynamic combinatorial libraries (DCLs), but the resulting receptors have primarily been utilized in isolation rather than as part of the entire library, with only a few examples that make use of the complexity of a library of receptors. Herein, we demonstrate a unique sensor array approach using "imprint-and-report" DCLs that obviates the need for receptor synthesis and isolation. This strategy leverages information stored in DCLs in the form of differential library speciation to provide a high-throughput method for both developing a sensor array and analyzing data for analyte differentiation. First, each DCL is templated with analyte to give an imprinted library, followed by in situ fluorescent indicator displacement analysis. We further demonstrate that the reverse strategy, imprinting with the fluorescent reporter followed by displacement with each analyte, provides a more sensitive method for differentiating analytes. We describe the development of this differential sensing system using the methylated Arg and Lys post-translational modifications (PTMs). Altogether, 19 combinations of 3-5 DCL data sets that discriminate all 7 PTMs were identified. Thus, a comparable sensor array workflow results in a larger payoff due to the immense information stored within multiple noncovalent networks.
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Aboriginal 'gathering places' have been described as cultural hubs, healing centres, and social meeting places. This article explores a gap in the literature on the health and wellbeing outcomes of gathering places from the perspectives of Aboriginal people who attend them. The aim of this study was to develop a framework to articulate the enablers, principles, and outcomes of 'successful' Aboriginal gathering places. In this study, sixty-nine (n = 69) community members participated in qualitative interviews or focus group discussions across thirteen gathering place sites in Victoria (Australia). The research found that gathering places address social health disparities through the provision of a broad range of health and wellbeing programs that benefit Aboriginal community members accessing them. Gathering places were described by participants as providing connections to place, Aboriginal culture, and healing and mainstream health services that enhanced wellbeing. These findings contribute to a better understanding of how Aboriginal gathering places function and offer strategies for creating culturally safe and welcoming settings for Aboriginal peoples, with potential for consideration in international contexts. This research informed a best-practice framework and outlines different models for developing community empowering and culturally affirming gathering places for improving Aboriginal people's access to culturally appropriate health and support services, while simultaneously reducing health and social inequalities. Key elements of this framework that contribute to a successful gathering place include the people, place (location/facilities), programs and community themselves, whilst the principles that enable these places include elements like self-determination, respect of culture, sustainability and strong governance.
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Serviços de Saúde do Indígena , Grupos Focais , Humanos , Havaiano Nativo ou Outro Ilhéu do Pacífico , VitóriaRESUMO
Rice (Oryza sativa) is a water-intensive crop, and like other plants uses stomata to balance CO2 uptake with water-loss. To identify agronomic traits related to rice stomatal complexes, an anatomical screen of 64 Thai and 100 global rice cultivars was undertaken. Epidermal outgrowths called papillae were identified on the stomatal subsidiary cells of all cultivars. These were also detected on eight other species of the Oryza genus but not on the stomata of any other plant species we surveyed. Our rice screen identified two cultivars that had "mega-papillae" that were so large or abundant that their stomatal pores were partially occluded; Kalubala Vee had extra-large papillae, and Dharia had approximately twice the normal number of papillae. These were most accentuated on the flag leaves, but mega-papillae were also detectable on earlier forming leaves. Energy dispersive X-Ray spectrometry revealed that silicon is the major component of stomatal papillae. We studied the potential function(s) of mega-papillae by assessing gas exchange and pathogen infection rates. Under saturating light conditions, mega-papillae bearing cultivars had reduced stomatal conductance and their stomata were slower to close and re-open, but photosynthetic assimilation was not significantly affected. Assessment of an F3 hybrid population treated with Xanthomonas oryzae pv. oryzicola indicated that subsidiary cell mega-papillae may aid in preventing bacterial leaf streak infection. Our results highlight stomatal mega-papillae as a novel rice trait that influences gas exchange, stomatal dynamics, and defense against stomatal pathogens which we propose could benefit the performance of future rice crops.
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Selective molecular recognition of hydrophilic guests in water plays a fundamental role in a vast number of biological processes, but synthetic mimicry of biomolecular recognition in water still proves challenging both in terms of achieving comparable affinities and selectivities. This Review highlights strategies that have been developed in the field of supramolecular chemistry to selectively and non-covalently bind three classes of biologically relevant molecules: nucleotides, carbohydrates, and amino acids. As several groups have systematically modified receptors for a specific guest, an evolutionary perspective is also provided in some cases. Trends in the most effective binding forces for each class are described, providing insight into selectivity and potential directions for future work.
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Carboidratos , Água , Interações Hidrofóbicas e HidrofílicasRESUMO
BACKGROUND: Exercise-induced gait deterioration is a frequently encountered symptom that limits ambulation throughout the clinical course, becoming more prominent with increasing neurological disability in people with MS (pwMS). OBJECTIVE: We attempted to objectively document exercise-induced gait changes in pwMS with minimal neurological disability and stable disease. METHODS: Gait kinematics and spatio-temporal parameters were recorded using 3D motion analysis before and after a 20-minute treadmill walk (Group A, n=15)/run (Group B, n=15) at a self-selected speed in pwMS and compared with healthy controls (n=15). RESULTS: Gait analysis revealed a significant decrease in peak ankle dorsiflexion in swing of the most affected leg, post-exercise task, in both Group A (EDSS 2.5-3.5) and Group B (EDSS 1-2.5) and not in healthy controls. Fourteen out of 30 MS participants showed an exercise-induced gait deterioration, based on minimal detectable change. Pre-exercise gait parameters in Group A showed a significantly higher peak dorsiflexion in swing with shorter step length and higher cadence, whereas Group B was comparable to healthy controls. CONCLUSION: The detection of exercise-induced gait deterioration (foot drop) in pwMS with minimal neurological disability and stable disease indicates the potential of gait kinematics, before and after an exercise task, to monitor subtle neurological deficits from an early stage of MS.
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Transtornos Neurológicos da Marcha , Esclerose Múltipla , Fenômenos Biomecânicos , Marcha , Transtornos Neurológicos da Marcha/etiologia , Humanos , Esclerose Múltipla/complicações , CaminhadaRESUMO
Lung squamous carcinoma (LUSC) is a highly metastatic disease with a poor prognosis. Using an integrated screening approach, we found that miR-671-5p reduces LUSC metastasis by inhibiting a circular RNA (circRNA), CDR1as. Although the putative function of circRNA is through miRNA sponging, we found that miR-671-5p more potently silenced an axis of CDR1as and its antisense transcript, cerebellar degeneration related protein 1 (CDR1). Silencing of CDR1as or CDR1 significantly inhibited LUSC metastases and CDR1 was sufficient to promote migration and metastases. CDR1, which directly interacted with adaptor protein 1 (AP1) complex subunits and coatomer protein I (COPI) proteins, no longer promoted migration upon blockade of Golgi trafficking. Therapeutic inhibition of the CDR1as/CDR1 axis with miR-671-5p mimics reduced metastasis in vivo. This report demonstrates a novel role for CDR1 in promoting metastasis and Golgi trafficking. These findings reveal an miRNA/circRNA axis that regulates LUSC metastases through a previously unstudied protein, CDR1. SIGNIFICANCE: This study shows that circRNA, CDR1as, promotes lung squamous migration, metastasis, and Golgi trafficking through its complimentary transcript, CDR1.
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Autoantígenos/metabolismo , Carcinoma de Células Escamosas/secundário , Complexo de Golgi/metabolismo , Neoplasias Pulmonares/patologia , Proteínas do Tecido Nervoso/metabolismo , RNA Circular/antagonistas & inibidores , RNA Longo não Codificante/metabolismo , Complexo 1 de Proteínas Adaptadoras/metabolismo , Animais , Autoantígenos/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidade , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Complexo I de Proteína do Envoltório/metabolismo , Retículo Endoplasmático/metabolismo , Feminino , Humanos , Ácido Hialurônico/uso terapêutico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Camundongos , Camundongos Nus , MicroRNAs/metabolismo , Nanopartículas/uso terapêutico , Metástase Neoplásica , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas do Tecido Nervoso/genéticaRESUMO
CpG oligodeoxynucleotides are potent toll-like receptor (TLR) 9 agonists and have shown promise as anticancer agents in preclinical studies and clinical trials. Binding of CpG to TLR9 initiates a cascade of innate and adaptive immune responses, beginning with activation of dendritic cells and resulting in a range of secondary effects that include the secretion of pro-inflammatory cytokines, activation of natural killer cells, and expansion of T cell populations. Recent literature suggests that local delivery of CpG in tumors results in superior antitumor effects as compared to systemic delivery. In this study, we utilized PRINT (particle replication in nonwetting templates) nanoparticles as a vehicle to deliver CpG into murine lungs through orotracheal instillations. In two murine orthotopic metastasis models of non-small-cell lung cancer-344SQ (lung adenocarcinoma) and KAL-LN2E1 (lung squamous carcinoma), local delivery of PRINT-CpG into the lungs effectively promoted substantial tumor regression and also limited systemic toxicities associated with soluble CpG. Furthermore, cured mice were completely resistant to tumor rechallenge. Additionally, nanodelivery showed extended retention of CpG within the lungs as well as prolonged elevation of antitumor cytokines in the lungs, but no elevated levels of proinflammatory cytokines in the serum. These results demonstrate that PRINT-CpG is a potent nanoplatform for local treatment of lung cancer that has collateral therapeutic effects on systemic disease and an encouraging toxicity profile and may have the potential to treat lung metastasis of other cancer types.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nanopartículas , Animais , Pulmão , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Oligodesoxirribonucleotídeos , Receptor Toll-Like 9RESUMO
In the early months of the COVID-19 epidemic, some have wondered if the force of this global experience will solve the problem of vaccine refusal that has vexed and preoccupied the global public health community for the last several decades. Drawing on historical and epidemiological analyses, we critique contemporary approaches to reducing vaccine hesitancy and articulate our notion of vaccine confidence as an expanded way of conceptualizing the problem and how to respond to it. Intervening on the rush of vaccine optimism we see pervading present discourse around the COVID-19 epidemic, we call for a re-imagination of the culture of public health and the meaning of vaccine safety regulations. Public confidence in vaccination programs depends on the work they do for the community-social, political, and moral as well as biological. The concept of public health and its programs must be broader than the delivery of the vaccine technology itself. The narrative work and policy actions entailed in actualizing such changes will, we expect, be essential in achieving a true vaccine confidence, however the public reacts to the specific vaccine that may be developed for COVID-19.
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Infecções por Coronavirus/epidemiologia , Epidemias , Pneumonia Viral/epidemiologia , Opinião Pública , Vacinas , COVID-19 , Infecções por Coronavirus/prevenção & controle , Humanos , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Estados Unidos/epidemiologia , Recusa de Vacinação , Vacinas/administração & dosagemRESUMO
Air-stable iron carbonyl compounds bearing cyclopentadienone ligands with varying substitution were explored as catalysts in dehydrogenative diol lactonization reactions using acetone as both the solvent and hydrogen acceptor. Two catalysts with trimethylsilyl groups in the 2- and 5-positions, [2,5-(SiMe3)2-3,4-(CH2)4(η4-C4CâO)]Fe(CO)3 (1) and [2,5-(SiMe3)2-3,4-(CH2)3(η4-C4CâO)]Fe(CO)3 (2), were found to be the most active, with 2 being the most selective in the lactonization of diols containing both primary and secondary alcohols. Lactones containing five-, six-, and seven-membered rings were successfully synthesized, and no over-oxidations to carboxylic acids were detected. The lactonization of unsymmetrical diols containing two primary alcohols occurred with catalyst 1, but selectivity was low based on alcohol electronics and modest based on alcohol sterics. Evidence for a transfer dehydrogenation mechanism was found, and insight into the origin of selectivity in the lactonization of 1°/2° diols was obtained. Additionally, spectroscopic evidence for a trimethylamine-ligated iron species formed in solution during the reaction was discovered.
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The intricate and interconnecting reactions of C3 photosynthesis are often limited by one of two fundamental processes: the conversion of solar energy into chemical energy, or the diffusion of CO2 from the atmosphere through the stomata, and ultimately into the chloroplast. In this review, we explore how the contributions of stomatal morphology and distribution can affect photosynthesis, through changes in gaseous exchange. The factors driving this relationship are considered, and recent results from studies investigating the effects of stomatal shape, size, density and patterning on photosynthesis are discussed. We suggest that the interplay between stomatal gaseous exchange and photosynthesis is complex, and that a disconnect often exists between the rates of CO2 diffusion and photosynthetic carbon fixation. The mechanisms that allow for substantial reductions in maximum stomatal conductance without affecting photosynthesis are highly dependent on environmental factors, such as light intensity, and could be exploited to improve crop performance.