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Understanding the intricate factors governing intersystem crossing (ISC) in aromatic carbonyl compounds remains a long-standing interest among researchers. This study unveils the crucial roles of vibration in influencing the ISC of a typical aromatic carbonyl chromophore, benzanthrone, and how hydrogen bonding and solvent viscosity affect these vibrations and, thus, the associated ISC kinetics. We demonstrate that for benzanthrone, the ISC is exceedingly facile in an aprotic solvent, while in protic solvents, the ISC is significantly suppressed through the formation of the hydrogen-bonded state. Moreover, in a high-viscosity medium, ISC is further retarded due to restrictions of volume-changing motions, which may assist ISC. Theoretical calculations revealed that the CâO bond vibration and specific out-of-plane vibrations accompanying a volume change could be the probable coordinates for ISC. These findings provide valuable insights for tailoring the excited-state behavior of carbonyl-functionalized materials for diverse applications in photocatalysis, organic electronics, and biomedicine.
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The photochemistry and photophysics of thiocarbonyl compounds, analogues of carbonyl compounds with sulfur, have long been overshadowed by their counterparts. However, recent interest in visible light reactions has reignited attention toward these compounds due to their unique excited-state properties. This study delves into the ultrafast dynamics of 7-diethylaminothiocoumarin (TC1), a close analogue of the well-known probe molecule coumarin 1 (C1), to estimate intersystem crossing rates, understand the mechanisms of fluorescence and phosphorescence, and evaluate TC1's potential as a solvation dynamics probe. Enclosing TC1 within an organic capsule indicates its potential applications, even in aqueous environments. Ultrafast studies reveal a dominant subpicosecond intersystem crossing process, indicating the importance of upper excited singlet and triplet states in the molecule's photochemistry. The distinct fluorescence and phosphorescence origins, along with the presence of closely spaced singlet excited states, support the observed efficient intersystem crossing. The sulfur atom alters the excited-state behavior, shedding light on reactive triplet states and paving the way for further investigations.
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Gorlin-Goltz syndrome (GGS) is an infrequent multisystemic disease with an autosomal dominant trait, which depicted presence of numerous basal cell carcinoma in conjunction with multiorgan abnormalities. This syndrome may be diagnosed early by a dentist by routine radiographic exams in the first decade of life, since the keratocystic odontogenic tumour are usually one of the first manifestations of the syndrome. This article includes a case report of the GGS with regard to its history, incidence, etiology, features, investigations, diagnostic criteria, keratocystic odontogenic tumour and treatment modalities.
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Síndrome do Nevo Basocelular , Carcinoma Basocelular , Tumores Odontogênicos , Neoplasias Cutâneas , Criança , Humanos , Síndrome do Nevo Basocelular/diagnóstico , FenótipoRESUMO
Recent restrictions on marine fuel sulfur content and a heightened regulatory focus on maritime decarbonization are driving the deployment of low-carbon and low-sulfur alternative fuels for maritime transport. In this study, we quantified the life-cycle greenhouse gas and sulfur oxide emissions of several novel marine biofuel candidates and benchmarked the results against the emissions reduction targets set by the International Maritime Organization. A total of 11 biofuel pathways via four conversion processes are considered, including (1) biocrudes derived from hydrothermal liquefaction of wastewater sludge and manure, (2) bio-oils from catalytic fast pyrolysis of woody biomass, (3) diesel via Fischer-Tropsch synthesis of landfill gas, and (4) lignin ethanol oil from reductive catalytic fractionation of poplar. Our analysis reveals that marine biofuels' life-cycle greenhouse gas emissions range from -60 to 56 gCO2e MJ-1, representing a 41-163% reduction compared with conventional low-sulfur fuel oil, thus demonstrating a considerable potential for decarbonizing the maritime sector. Due to the net-negative carbon emissions from their life cycles, all waste-based pathways showed over 100% greenhouse gas reduction potential with respect to low-sulfur fuel oil. However, while most biofuel feedstocks have a naturally occurring low-sulfur content, the waste feedstocks considered here have higher sulfur content, requiring hydrotreating prior to use as a marine fuel. Combining the break-even price estimates from a published techno-economic analysis, which was performed concurrently with this study, the marginal greenhouse gas abatement cost was estimated to range from -$120 to $370 tCO2e-1 across the pathways considered. Lower marginal greenhouse gas abatement costs were associated with waste-based pathways, while higher marginal greenhouse gas abatement costs were associated with the other biomass-based pathways. Except for lignin ethanol oil, all candidates show the potential to be competitive with a carbon credit of $200 tCO2e-1 in 2016 dollars, which is within the range of prices recently received in connection with California's low-carbon fuel standard.
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Óleos Combustíveis , Gases de Efeito Estufa , Animais , Biocombustíveis , Lignina , Pirólise , Madeira , Enxofre , Carbono , Etanol , Estágios do Ciclo de VidaRESUMO
Renewable, low-carbon biofuels offer the potential opportunity to decarbonize marine transportation. This paper presents a comparative techno-economic analysis and process sustainability assessment of four conversion pathways: (1) hydrothermal liquefaction (HTL) of wet wastes such as sewage sludge and manure; (2) fast pyrolysis of woody biomass; (3) landfill gas Fischer-Tropsch synthesis; and (4) lignin-ethanol oil from the lignocellulosic ethanol biorefinery utilizing reductive catalytic fractionation. These alternative marine biofuels have a modeled minimum fuel selling price between $1.68 and $3.98 per heavy fuel oil gallon equivalent in 2016 U.S. dollars based on a mature plant assessment. The selected pathways also exhibit good process sustainability performance in terms of water intensity compared to the petroleum refineries. Further, the O and S contents of the biofuels vary widely. While the non-HTL biofuels exhibit negligible S content, the raw biocrudes via HTL pathways from sludge and manure show relatively high S contents (>0.5 wt %). Partial or full hydrotreatment can effectively lower the biocrude S content. Additionally, co-feeding with other low-sulfur wet wastes such as food waste can provide another option to produce raw biocrude with lower S content to meet the target with further hydrotreatment. This study indicates that biofuels could be a cost-effective fuel option for the marine sector. Marine biofuels derived from various feedstocks and conversion technologies could mitigate marine biofuel adoption risk in terms of feedstock availability and biorefinery economics.
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Biocombustíveis , Eliminação de Resíduos , Esgotos , Esterco , Alimentos , Biomassa , EtanolRESUMO
To mitigate green-house gas (GHG) emissions, governments around the world are enacting legislation to reduce carbon intensity in transportation fuels. Coprocessing biomass and petroleum-derived liquids in existing refineries is a near-term, cost-effective approach for introducing renewable carbon in fuels and enabling refineries to meet regulatory mandates. However, coprocessing biomass-derived liquids in refineries results in variable degrees of biogenic carbon incorporation, necessitating accurate quantification to verify compliance with mandates. Existing refinery control and instrumentation systems lack the means to measure renewable carbon accurately, reliably, and quickly. Thus, accurate measurement of biogenic carbon is key to ensuring refineries meet regulatory mandates. In this Perspective, we present existing methods for measuring biogenic carbon, point out their challenges, and discuss the need for new online analytical capabilities to measure biogenic carbon in fuel intermediates.
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Petróleo , Biomassa , Carbono , Pegada de Carbono , Efeito EstufaRESUMO
Thermodynamics, the science of energy interactions, governs the direction of processes found in nature. While the subject finds wide applications in science and technology, its connection to biological sciences and in particular to bio-engineering is becoming increasingly important. In this work, after a brief introduction to the fundamental concepts in thermodynamics, we focus on its application in human physiology. A review of application of thermodynamics to the interaction between human body and environment is presented. Research works on biological systems such as the nervous system and the cardiovascular systems are summarized. The thermodynamics of metabolism is reviewed, and finally, the role of the subject in understanding and combating diseases is highlighted.
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TermodinâmicaRESUMO
In this work, analysis of cardiovascular system under the influence of RNA virus infection has been performed from a thermodynamic perspective. An exergetic efficiency of the system has been defined for this purpose. Results show that except for asymptomatic case, the exergetic efficiency reduces as the viral load goes up. Dynamics of viral growth along with change in efficiency is examined under different parameters such as virus production rate, infectivity rate and cell death rate. Results show that the drop in the exergetic efficiency of cardiovascular system under viral infection can be up to about 20%. Under infection, the exergy requirement of the lungs increases significantly as the work rate required by lungs increase by up to 240%.
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Sistema Cardiovascular/fisiopatologia , Modelos Cardiovasculares , Infecções por Vírus de RNA/fisiopatologia , Termodinâmica , Sistema Cardiovascular/virologia , Humanos , Pulmão/virologia , Infecções por Vírus de RNA/virologia , Vírus de RNA/patogenicidade , Vírus de RNA/fisiologia , Replicação ViralRESUMO
The purpose of this study is to develop a comprehensive thermodynamic model of the human respiratory system and quantify the effects of inspiratory air temperature, relative humidity (RH), lung capacity and O2 fluctuation in metabolic reaction on the human respiratory system under three different physiological conditions, i.e. rest, moderate level of physical activity and extreme level of physical activity. Therefore, a second law-based analysis has carried out for the human respiratory system. It is observed that exergetic efficiency decreases by 21% and 16.5% during moderate and extreme level of activity respectively as compared to the physical condition of rest. The respiratory efficiency also increases with the increase in inspiratory air temperature and RH. For a given inspiratory air temperature, an increase in lung volume leads to a reduction in the efficiency. Increase in TV with a high airflow rate gives a higher magnitude of efficiency, such a situation appearing when a person's lung compliance harmed due to diseases. The respiratory efficiency decreases up to 2% with the increase in O2 percentage. The efficiency of the respiratory system is in maximum during rest followed by an extreme and moderate level of activity. However, with the controlled supply of O2, the efficiency of the human respiratory performance increases with the decrease in O2 percentage. Due to partial oxidation of glucose at a reduced O2 level, exergy input from the metabolic reaction is less leading to increased exergetic efficiency.
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Modelos Biológicos , Fenômenos Fisiológicos Respiratórios , Termodinâmica , Humanos , Umidade , Oxigênio , Sistema Respiratório , TemperaturaRESUMO
In this mini-review we compare two prototypical metal foam electrocatalysts applied to the transformation of CO2 into value-added products (e.g. alcohols on Cu foams and formate on Bi foams). A substantial improvement in the catalyst performance is typically achieved through thermal annealing of the as-deposited foam materials, followed by the electro-reduction of the pre-formed oxidic precursors prior or during the actual CO2 electrolysis. Utilizing highly insightful and sensitive complementary operando analytical techniques (XAS, XRD, and Raman spectroscopy) we demonstrate that this catalyst pre-activation process is entirely accomplished in case of the oxidized Cu foams prior to the formation of hydrocarbons and alcohols from the CO2. The actually active catalyst is therefore the metallic Cu derived from the precursor by means of oxide electro-reduction. Conversely, in their oxidic form, the Cu-based foam catalysts are inactive towards the CO2 reduction reaction (denoted ec-CO2 RR). Oxidized Bi foams can be regarded as an excellent counter example to the above-mentioned Cu case as both metallic and the thermally derived oxidic Bi foams are highly active towards ec-CO2 RR (formate production). Indeed, operando Raman spectroscopy reveals that CO2 electrolysis occurs upon its embedment into the oxidic Bi2O3 foam precursor, which itself undergoes partial transformation into an active sub-carbonate phase. The potential-dependent transition of sub-carbonates/oxides into the corresponding metallic Bi foam dictates the characteristic changes of the ec-CO2 RR pathway. Identical location (IL) microscopic inspection of the catalyst materials, e.g. by means of scanning electron microscopy, demonstrates substantial morphological alterations on the nm length scale on the material surface as consequence of the sub-carbonate formation and the potential-driven oxide reduction into the metallic Bi foam. The foam morphology on a mesoscopic length scale (macroporosity) remains, by contrast, fully unaffected by these phase transitions.
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Homeopathic education has passed through significant incremental changes in the past few years, where especially postgraduate education has become increasingly slanted toward advanced knowledge of clinical work and research methods. Among many educational activities, a great source of learning is from presenting at or attending a journal club meeting, which is a gathering of people to learn and to critically appraise a journal article or other study material. There has been little previous guidance in homeopathy regarding how to prepare and present journal club content. Selection of a suitable topic is one of the critical prerequisites. Each and every step, from preparation to presentation, needs to be carefully planned and considered. For the meeting to be successful, the final discussion phase requires the active participation and critical insight of all those attending.
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Processos Grupais , Homeopatia/educação , Publicações Periódicas como Assunto , HumanosRESUMO
Postmenopause is a phase of life which leads physical and emotional instability from multiple health related issues. Oral health in this stage of life is also compromised. Oral health has an impact on general wellbeing of the individual as oral cavity is commonly act as a mirror to general health. Menopause is phase in a woman's life when menstrual cycles cease by reduced secretion of the ovarian hormones, such as estrogen and progesterone. This review article has emphasized on the diverse oral presentations of peri- and postmenopausal phase of women's life. Practicing dental surgeons and general physician should be aware of the possible association of postmenopause and its various oral signs and symptoms in this midlife phase of women. It also focuses on its symptomatic management of various oral health issues. This article explains diverse oral conditions in detailed and their management. Stress causing anxiety and depression among this midlife phase of women can lead to alteration in immunity which can again lead to various oral conditions, like lichen planus, apthous ulcer that can cause burning sensation in oral mucosa and alter the food habit. By dealing with all this diverse condition, practicing oral physician can help to reduce and manage oral manifestation of postmenopausal phase of life.
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Herein, we discuss recent research activities on the electrochemical water/CO2 co-electrolysis at the Department of Chemistry and Biochemistry of the University of Bern (Arenz and Broekmann research groups). For the electrochemical conversion of the greenhouse gas CO2 into products of higher value catalysts for two half-cell reactions need to be developed, i.e. catalysts for the reductive conversion of CO2 (CO2RR) as well as catalysts for the oxidative splitting of water (OER: Oxygen Evolution Reaction). In research, the catalysts are often investigated independently of each other as they can later easily be combined in a technical electrolysis cell. CO2RR catalysts consist of abundant materials such as copper and silver and thus mainly the product selectivity of the respective catalyst is in focus of the investigation. In contrast to that, OER catalysts (in acidic conditions) mainly consist of precious metals, e.g. Ir, and therefore the minimization of the catalytic current per gram Ir is of fundamental importance.
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A new coumarin based Schiff-base chemosensor-(E)-7-(((8-hydroxyquinolin-2-yl)methylene) amino)-4-methyl-2H-chromen-2-one (H 11 L) was synthesized and evaluated as a colorimetric sensor for Fe3+ and fluorescence "turn on-off" response of Zn2+ and Cu2+ using absorption and fluorescence spectroscopy. Upon treatment with Fe3+ and Zn2+, the absorption intensity as well as the fluorescence emission intensity increases drastically compared to other common alkali, alkaline earth and transition metal ions, with a distinct color change which provide naked eye detection. Formation of 1:1 metal to ligand complex has been evaluated using Benesi-Hildebrand relation, Job's plot analyses, 1H NMR titration as well as ESI-Mass spectral analysis. The complex solution of H 11 L with Zn2+ ion exhibited reversibility with EDTA and regenerate free ligand for further Zn2+ sensing. H 11 L exhibits two INHIBIT logic gates with two different chemical inputs (i) Zn2+ (IN1) and Cu2+ (IN2) and (ii) Zn2+ (IN1) and EDTA (IN2) and the emission as output. Again, an IMPLICATION logic gate is obtained with Cu2+ and EDTA as chemical inputs and emission as output mode. Both free ligand as well as metal-complexes was optimized using density functional theory to interpret spectral properties. The corresponding energy difference between HOMO-LUMO energy gap for H 11 L, H11L-Zn2+ and H11L-Cu2+ are 2.193, 1.834 and 0.172 eV, respectively.
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Woolly hair may occur as an isolated problem of cosmetic concern or can be a part of a systemic disease (woolly hair syndrome) with underlying fatal cardiomyopathy. Two characteristic associations of woolly hair syndrome are Naxos disease and Carvajal syndrome. Naxos disease is characterized by woolly hair, palmoplantar keratoderma, and arrythmogenic right ventricular cardiomyopathy.In this report we describe a case of a young girl who presented with heart failure and was subsequently diagnosed as a case of generalized woolly hair with biventricular arrythmogenic cardiomyopathy.Our case represented a rare variant of Naxos disease in the advanced stage of arrythmogenic right ventricular cardiomyopathy; biventricular failure may occur with involvement of the interventricular septum and left ventricle causing congestive heart failure.
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Displasia Arritmogênica Ventricular Direita/diagnóstico , Doenças do Cabelo/diagnóstico , Ceratodermia Palmar e Plantar/diagnóstico , Disfunção Ventricular Esquerda/diagnóstico , Displasia Arritmogênica Ventricular Direita/diagnóstico por imagem , Displasia Arritmogênica Ventricular Direita/patologia , Displasia Arritmogênica Ventricular Direita/fisiopatologia , Pré-Escolar , Ecocardiografia , Eletrocardiografia , Feminino , Doenças do Cabelo/diagnóstico por imagem , Doenças do Cabelo/patologia , Doenças do Cabelo/fisiopatologia , Humanos , Ceratodermia Palmar e Plantar/diagnóstico por imagem , Ceratodermia Palmar e Plantar/patologia , Ceratodermia Palmar e Plantar/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
The electrochemical reduction of CO(2) has been extensively studied over the past decades. Nevertheless, this topic has been tackled so far only by using a very fundamental approach and mostly by trying to improve kinetics and selectivities toward specific products in half-cell configurations and liquid-based electrolytes. The main drawback of this approach is that, due to the low solubility of CO(2) in water, the maximum CO(2) reduction current which could be drawn falls in the range of 0.01-0.02 A cm(-2). This is at least an order of magnitude lower current density than the requirement to make CO(2)-electrolysis a technically and economically feasible option for transformation of CO(2) into chemical feedstock or fuel thereby closing the CO(2) cycle. This work attempts to give a short overview on the status of electrochemical CO(2) reduction with respect to challenges at the electrolysis cell as well as at the catalyst level. We will critically discuss possible pathways to increase both operating current density and conversion efficiency in order to close the gap with established energy conversion technologies.
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Chronic Subdural Hematoma is a prevalent neurosurgical disorder associated with old age, often resulting from trauma. The condition has limited scope for conservative management, and invasive techniques are frequently used as preferred treatment. Complications often arise due to comorbidities associated with old age. This case details the treatment of the condition in a 71-year-old patient who presented with seizures, hemiparesis, tremor, and disorientation. The patient had a history of a fall a few weeks prior. Initially, the condition was managed through surgery, but recurrence occurred, accompanied by concurrent neurological signs. The patient was subsequently treated with Hamamelis virginica 200CH through homeopathic approach. Following this treatment, the patient returned to his previous state within seven days. No recurrence was observed during the three-month follow-up. This case underscores a positive role of homeopathic medicines in managing neurosurgical conditions such as subdural hematoma. The positive outcomes of this study provide preliminary evidence that may eventually contribute to the design of appropriate clinical trials.
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Density functional theory (DFT) investigation has been done to unravel the adsorption and dissociation nature of hydrogen molecule on 3d, 4d and 5d transition metal (M = Fe, Co, Ni, Cu, Ru, Rh, Pd, Ag, Os, Ir, Pt or Au) atom doped activated carbon (AC) surface. Transition metal doped AC are found to be active catalyst for storage of hydrogen and also gives the stability of M - H bonds formed after bond breakage of H2 molecule. Transition metals are found to occupy the position on the five member ring rather than six member ring of the AC. Five member ring of the AC is seen to be more deformed than the six-member ring on metal doping. Higher values of LUMO-HOMO gap and vertical ionization potential and lower electron affinity signify the higher stability of hydrogen molecule adsorbed metal doped AC. Bond length and vibrational analysis of the adsorbed hydrogen molecule suggest the higher activation of hydrogen molecule on AC, where 4d and 5d metal doped ACs are found to be more efficient in comparison to 3d metal. Adsorbed hydrogen molecule on metal doped AC follows dissociation either via spill-over or via normal process. DFT evaluated rate constant and the transition states suggest that Ru, Rh, Os and Ir doped AC are found to be efficient in the dissociation of hydrogen molecule, while, Cu doped AC is seen to be worst in the same reaction. Deformed electron density, HOMO-LUMO isosurface, and density of states confirms the redistribution of electrons among H2 and metal doped AC surface. ΔGH values of Hydrogen evolution reaction also signifies the greater catalytic activities of Ru and Os supported activated carbon towards HER.
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Hidrogênio , Teoria Quântica , Energia Renovável , Elementos de Transição , Hidrogênio/química , Adsorção , Catálise , Elementos de Transição/química , Carvão Vegetal/química , Modelos Moleculares , Teoria da Densidade FuncionalRESUMO
INTRODUCTION: Homeopathic medicines have been used for decades in the prevention and treatment of infectious diseases. However, the preventive efficacy of specific homeopathic medicines in COVID-19 is not well characterized. This study aimed to evaluate the comparative efficacy of prespecified homeopathic medicines in preventing COVID-19. METHODS: A community-based, double-blind, randomized, placebo-controlled trial was conducted on 4,034 participants residing in Ward No. 27 of the Howrah Municipal Corporation in India. Participants were randomized to receive one of three prespecified homeopathic medicines [Influenzinum 30C, Arsenicum album 30C, Anas barbariae hepatis et cordis extractum 200K (Oscillococcinum®)], or placebo. The outcomes were the incidence of laboratory-confirmed and suspected cases of COVID-19 during a follow-up period of 1 month. RESULTS: During the follow-up period, a total of 13 new laboratory-confirmed COVID-19 cases were reported in the study population. Among these, 5 cases in Influenzinum group, 2 cases in Arsenicum album group, 1 case in Oscillococcinum® group, and 5 cases in Placebo group were reported. On the other hand, number of suspected COVID-19 cases was significantly less in all the three homeopathic medicine groups compared to placebo. The least number of suspected cases reported in the Oscillococcinum® group (aOR: 0.058; 95% confidence interval [CI]: 0.029, 0.114), followed by the Arsenicum album (aOR: 0.337; 95% CI: 0.238, 0.475) and Influenzinum (aOR: 0.539; 95% CI: 0.401, 0.726) groups. CONCLUSION: Prespecified homeopathic medicines, particularly Oscillococcinum® and Arsenicum album 30C, may have a role in preventing COVID-19, especially in reducing the incidence of suspected or COVID-19-like respiratory illnesses. However, the result failed to demonstrate a statistically significant difference in the occurrence of confirmed cases of COVID-19 between the study groups. Further research is needed to evaluate the efficacy of these medicines in different populations and settings.