27 research outputs found

    Light-Off in Plasmon-Mediated Photocatalysis

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    In plasmon-mediated photocatalysis it is of critical importance to differentiate light-induced catalytic reaction rate enhancement channels, which include near-field effects, direct hot carrier injection, and photothermal catalyst heating. In particular, the discrimination of photothermal and hot electron channels is experimentally challenging, and their role is under keen debate. Here we demonstrate using the example of CO oxidation over nanofabricated neat Pd and Au50Pd50 alloy catalysts, how photothermal rate enhancement differs by up to 3 orders of magnitude for the same photon flux, and how this effect is controlled solely by the position of catalyst operation along the light-off curve measured in the dark. This highlights that small fluctuations in reactor temperature or temperature gradients across a sample may dramatically impact global and local photothermal rate enhancement, respectively, and thus control both the balance between different rate enhancement mechanisms and the way strategies to efficiently distinguish between them should be devised

    Italian Influence in a Portuguese Mannerist Painting (Part I): A New Palette with Original Orange and Green Pigments

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    The palette used by the Portuguese painter Pedro Nunes (1586–1637) in the large panel depicting The Descent from the Cross (460 × 304 cm) painted in 1620 for Évora’s cathedral was investigated with a combination of the visual inspection of the paint surface and the analysis of the paint layers with microscopic, spectroscopic, and chromatographic techniques. Green earth and an orange artificial arsenic sulphide, two pigments identified for the first time in Portuguese paintings of the sixteenth and seventeenth centuries, were found to be abundantly used in large areas of the composition. The results further reveal the choice of a rich palette also containing lead-white, lead-tin yellow, ochre, vermilion, verdigris, smalt, azurite, vegetable carbon black, and a red lake made of brazilwood and cochineal. All the pigments were bound in an oil-based medium. The introduction of two pigments new to the Portuguese conventional palette is a direct consequence of the painter’s training in Rome in the first decade of the seventeenth century.info:eu-repo/semantics/publishedVersio

    Italian Influence in a Portuguese Mannerist Painting (Part II): A Matter of Image or a Matter of Technique?

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    The panel depictingThe Descent from the Cross, painted in 1620 by the Portuguese artist PedroNunes (1586-1637), shows a clear Italian formal influence. The painter’s colour palette wasidentified in another paper. The panel is now investigated from a technical perspective,discussing aspects related to the support, preparatory system, and paint layer build-up. Theresearch is based on the visual inspection of the painting’s surface with complementaryimaging techniques and on the analysis of the materials from the preparatory layers withmicroscopic and spectroscopic techniques. The characterisation of the painting techniquerevealed an ingenious use of colour that is based on the understanding of the optical andhandling properties of oil paint. This knowledge is illustrated by the painter’s ability toexploit and combine a range of different oil painting techniques, such as glazing, scumbling,wet-in-wet, or wet-in-dry painting; by his formulation of a wide variety of pigment mixtures;and by his use of diverse and often complex layering systems - some quite unconventionalfor Portuguese painting practice. The material and technical originality of this paintingclearly reflects Nunes’international Roman experience and his desire to update thePortuguese mainstream practice of his time

    Alleviation of drought stress through foliar application of thiamine in two varieties of pea (Pisum sativum L.)

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    Drought stress poorly impacts many morphological and physio-biochemical processes in plants. Pea (Pisum sativum L.) plants are highly nutritious crops destined for human consumption; however, their productivity is threatened under drought stress. Thiamine (vitamin B1) is well-known essential micronutrient, acting as a cofactor in key metabolic processes. Therefore, this study was designed to examine the protective effect of foliar application of thiamine (0, 250, and 500 ppm) on two varieties of pea plants under drought stress. Here, we conducted the pot experiment at the Government College Women University, Faisalabad, to investigate the physio-biochemical and morphological traits of two pea varieties (sarsabz and metior) grown under drought stress and thiamine treatment. Drought stress was applied to plants after germination period of 1 month. Results showed that root fresh and dry weight, shoot fresh and dry weight, number of pods, leaf area, total soluble sugars, total phenolics, total protein contents, catalase, peroxidase, and mineral ions were reduced against drought stress. However, the application of thiamine (both 250 and 500 ppm) overcome the stress and also enhances these parameters, and significantly increases the antioxidant activities (catalase and peroxidase). Moreover, the performance of sarsabz was better under control and drought stress conditions than metior variety. In conclusion, the exogenous application of thiamine enabled the plants to withstand drought stress conditions by regulating several physiological and biochemical mechanisms. In agriculture, it is a great latent to alleviate the antagonistic impact of drought stress on crops through the foliar application of thiamine

    A critical assessment of Mus musculus gene function prediction using integrated genomic evidence

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    Background: Several years after sequencing the human genome and the mouse genome, much remains to be discovered about the functions of most human and mouse genes. Computational prediction of gene function promises to help focus limited experimental resources on the most likely hypotheses. Several algorithms using diverse genomic data have been applied to this task in model organisms; however, the performance of such approaches in mammals has not yet been evaluated. Results: In this study, a standardized collection of mouse functional genomic data was assembled; nine bioinformatics teams used this data set to independently train classifiers and generate predictions of function, as defined by Gene Ontology (GO) terms, for 21,603 mouse genes; and the best performing submissions were combined in a single set of predictions. We identified strengths and weaknesses of current functional genomic data sets and compared the performance of function prediction algorithms. This analysis inferred functions for 76% of mouse genes, including 5,000 currently uncharacterized genes. At a recall rate of 20%, a unified set of predictions averaged 41% precision, with 26% of GO terms achieving a precision better than 90%. Conclusion: We performed a systematic evaluation of diverse, independently developed computational approaches for predicting gene function from heterogeneous data sources in mammals. The results show that currently available data for mammals allows predictions with both breadth and accuracy. Importantly, many highly novel predictions emerge for the 38% of mouse genes that remain uncharacterized

    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

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    Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

    Geraniolun Sıçanlarda Anksiyete/Depresyon Benzeri Davranış ve Hipokampal Kolinerjik Sistem Üzerine Etkileri

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    Amaç: Kronik stresin depresyon benzeri davranışları arttırdığı bilinmektedir. Geraniol nöromodülatör ve antidepresan etkileri bilinen doğal bir monoterpendir. Bu çalışma, kronik kısıtlama stresi depresyon modeli sıçanlarda geraniolun kolinerjik sistem üzerine olası etkilerini araştırmak için tasarlanmıştır. Gereç ve Yöntem: Çalışmada erişkin 21 adet dişi sıçan kullanıldı. Sıçanlara 3 hafta süreyle günde 5 saat kısıtlama stresi uygulandı. Geraniol oral gavaj yoluyla 100 mg/kg uygulandı. Stres ve ilaç uygulamalarını takiben açık alan testi ile anksiyete, zorunlu yüzme testi ile depresyon benzeri davranışlar değerlendirildi. Daha sonra sıçanlar ötenazi edilerek hipokampus disekte edildi. Asetilkolin (ACh) ve asetilkolinesteraz (AChE) düzeyleri hipokampal doku homojenatlarında ELISA yöntemi ile belirlendi. Bulgular: Stres maruziyeti anksiyete benzeri davranışı belirgin olarak etkilemedi ancak zorunlu yüzme testlerinde depresyon benzeri davranış parametrelerini uyardı. Geraniolun strese bağlı artan hareketsizlik süresini önemli ölçüde azalttığı tespit edildi (p0.05). Diğer yandan, kronik stres AChE düzeylerini önemli ölçüde azalttı (p0.05). Sonuç: Birlikte ele alındığında, bulgularımız kısıtlama stresinin sıçanlarda depresyon benzeri davranışı uyardığı, geraniol tedavisinin ise antidepresan benzeri etkilerini ortaya koydu. Bununla birlikte, geraniolun antidepresan benzeri etkisinin moleküler mekanizmasının ileri çalışmalarla araştırılmasını öneriyoruz.Objective: It is known that chronic stress increases depression-like behaviors. Geraniol is a natural monoterpene known for its neuromodulatory and antidepressant effects. This study was designed to investigate the possible effects of geraniol on the cholinergic system in chronic restraint stress depression model rats. Materials and Methods: 21 adult female rats were used in the study. Restraint stress was applied to rats for 5 hours a day for 3 weeks. Geraniol was administered at 100 mg/kg by oral gavage. Anxiety was evaluated with the open field test, and depression-like behaviors were evaluated with the forced swimming test following stress and drug administration. Then the rats were euthanized and the hippocampus was dissected. Acetylcholine (ACh) and acetylcholinesterase (AChE) levels were determined in hippocampal tissue homogenates by ELISA method. Results: Stress exposure did not significantly affect anxiety-like behavior, but it stimulated depression-like behavior parameters in forced swimming tests. It was determined that geraniol significantly decreased the increased immobility time due to stress (p0.05). On the other hand, chronic stress significantly decreased AChE levels (p0.05). Conclusion: Taken together, our findings revealed that restraint stress induces depression-like behavior in rats, while geraniol treatment has antidepressant-like effects. However, we suggest that the molecular mechanism of the antidepressant-like effect of geraniol be investigated with further studies

    Italian Influence in a Portuguese Mannerist Painting (Part II): A Matter of Image or a Matter of Technique?

    No full text
    The panel depicting The Descent from the Cross, painted in 1620 by the Portuguese artist Pedro Nunes (1586-1637), shows a clear Italian formal influence. The painter’s colour palette was identified in another paper. The panel is now investigated from a technical perspective, discussing aspects related to the support, preparatory system, and paint layer build-up. The research is based on the visual inspection of the painting’s surface with complementary imaging techniques and on the analysis of the materials from the preparatory layers with microscopic and spectroscopic techniques. The characterisation of the painting technique revealed an ingenious use of colour that is based on the understanding of the optical and handling properties of oil paint. This knowledge is illustrated by the painter’s ability to exploit and combine a range of different oil painting techniques, such as glazing, scumbling, wet-in-wet, or wet-in-dry painting; by his formulation of a wide variety of pigment mixtures; and by his use of diverse and often complex layering systems - some quite unconventional for Portuguese painting practice. The material and technical originality of this painting clearly reflects Nunes’ international Roman experience and his desire to update the Portuguese mainstream practice of his time.info:eu-repo/semantics/publishedVersio

    Italian Influence in a Portuguese Mannerist Painting (Part I): A New Palette with Original Orange and Green Pigments

    No full text
    The palette used by the Portuguese painter Pedro Nunes (1586–1637) in the large panel depicting The Descent from the Cross (460 × 304 cm) painted in 1620 for Évora’s cathedral was investigated with a combination of the visual inspection of the paint surface and the analysis of the paint layers with microscopic, spectroscopic, and chromatographic techniques. Green earth and an orange artificial arsenic sulphide, two pigments identified for the first time in Portuguese paintings of the sixteenth and seventeenth centuries, were found to be abundantly used in large areas of the composition. The results further reveal the choice of a rich palette also containing lead-white, lead-tin yellow, ochre, vermilion, verdigris, smalt, azurite, vegetable carbon black, and a red lake made of brazilwood and cochineal. All the pigments were bound in an oil-based medium. The introduction of two pigments new to the Portuguese conventional palette is a direct consequence of the painter’s training in Rome in the first decade of the seventeenth century
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