bluuebunny/crossref_metadata_2025 huggingface dataset:
Medición de la contribución de la bioeconomía en América Latina: caso Cuba
Authors: Rangel Cura Raúl A , Zúniga González Carlos A , Colón García Adelfa Patricia , Losilla Solano Luis , Berrios-Zepeda Roberto Arturo
Published: October 2015

La presente investigación constituye una primera aproximación para el caso de Cuba, a la medición de la contribución de la bioeconomía desde una perspectiva económica. Su desarrollo ha estado vinculado a la Red Iberoamericana de Bioeconomía y Cambio Climático (REBICAMCLI) financiada por el programa CYTED. Los datos utilizados fueron tomados en su mayoría del Anuario estadístico de Cuba, principal publicación de la Oficina Nacional de Estadística e Información (ONEI), donde se recogen las estadísticas oficiales del país. El año base que se toma para los análisis es 1997, que es el que se reconoce hasta la fecha como referencia oficial en el Sistema de Cuentas Nacionales. No obstante, dada la necesidad de cambiar el año base cada cierto tiempo, se conoce que éste está aún en proceso de cambio. Esta primera aproximación muestra un muy bajo nivel de aporte de la bioeconomía en Cuba, para un promedio de un 4%, cifra que pudiera incrementarse de contarse con una información más detallada a nivel del Sistema de Cuentas Nacionales. En cuanto a los factores que condicionan este bajo aporte, están problemas estructurales de la economía, como la doble circulación monetaria, las distorsiones de precios, los subsidios a la producción en el sector agrícola, entre otros.
Moringa oleifera as Sustainable Source for Energetic Biomass
Authors: Pereira Francisco , Silva Ana , Galvão Chesque , Lima Valmir , Montenegro Lucas , Lima-Filho Nelson , Silva Valdinete
Published: October 2015

This work investigated the biomasses (seeds, seed husks, oilseed grains, crude and purified oils, cakes by pressing and by hexane extraction and methyl biodiesel the oil) of Moringa oleifera Lamarck, starting with its seedpods (ripe and dry fruits) in energetic application. The oil obtained from the grains by mechanical pressing had an average yield of 11.36% and of 36.48% by hexane extraction. The moringa biomasses presented calorific values between 15.87 and 37.53 MJ/kg, being suitable as renewable biofuels. The mixed crude oil (1:4) was refined in four steps: degumming, neutralization, washing and drying. The crude and refined oils were characterised by acidity index, peroxide index, water content, turbidity, specific mass, kinematic viscosity, power calorific higher, calorific power below and ash content. The crude oils by pressing and by solvent extraction were characterised through of the saponification index and iodine value. The purified biodiesel presented specific mass of 889 kg/m3 (20 oC), kinematic viscosity of 5.5 m2/s (40 oC), content of ester of 86.2% and 98.23% (in microscale, ratifying the viability of the method), acidity index of 0.43 mg KOH/g and water content of 615.8 mg/kg. The solid moringa biomasses (seeds, cakes (or pies) and the seed husks) show high potential for the production of briquettes or ecological firewood due to its content energy expressed as lower calorific value (between 15.87 and 23.31 MJ/kg) and simple and accessible technological production. The results show that moringa is an easily exploitable plant in sustainable energy, especially from its seedpods and seeds.
Análise dos reflexos em prematuros submetidos ao posicionamento funcional em Terapia Intensiva Neonatal
Authors: Calazans Priscila Pinheiro Fernandes , Amaral Solange Pereira , Pinheiro Hudson Azevedo , Gardenghi Giulliano
Published: October 2015

Objetivo: Verificar se prematuros extremos, submetidos ao posicionamento funcional, conseguem adquirir integração dos reflexos primitivos quando comparados aos prematuros. Métodos: Trata-se de um relato de série de oito casos constituído de prematuros extremos e prematuros. Os bebês foram submetidos ao posicionamento funcional na Unidade de Terapia Intensiva Neonatal, na postura prona, supina e decúbito lateral, utilizando-se coxins para assegurar a contenção e oferecer a sensação de segurança, três vezes por dia, durante a internação. Os reflexos dos bebês foram avaliados no 30º e 60º dias de nascimento, de junho a outubro de 2012, por meio do Teste de Performance Infanto Motora (TIMP). Resultados: Observaram-se diferenças entre os escores das avaliações no TIMP após o 30º dia de vida entre os grupos; contudo, não se verificaram diferenças na avaliação aos 60 dias. Conclusão: Os bebês submetidos ao posicionamento funcional precoce, adquiriram adequada integração dos reflexos primitivos após 60 dias de vida.
Impacto da atividade física na hipertensão arterial em adolescentes com sobrepeso e obesidade
Authors: Corrêa Neto Victor Gonçalves , Palma Alexandre
Published: October 2015

Introdução: A obesidade é tida como importante fator de risco para hipertensão arterial sistêmica, enquanto a atividade física é vista como um agente protetor contra essa doença. Contudo, em grupos de adolescentes com excesso de peso, parecem existir poucas investigações sobre tais associações. Objetivo: Analisar a associação entre diferentes níveis de atividade física e HAS em uma amostra composta por adolescentes com sobrepeso e obesidade. Métodos: Selecionaram-se 181 adolescentes com sobrepeso e obesidade, sendo mensurados seus hábitos de prática de atividade física e sua pressão arterial. Um modelo de regressão de Poisson foi aplicado para determinar o impacto da atividade física na hipertensão arterial sistêmica. Resultado: Não existiu associação entre prática de atividade física e hipertensão arterial no grupo amostral investigado (p>0,05). Conclusão: Em adolescentes com sobrepeso e obesos, a atividade física não se caracterizou como um fator de proteção diante da hipertensão arterial sistêmica.
Impaired number and function of lymphocytes in patients with common variable immunodeficiency: a consequence of activation induced cell death
Authors: Errante Paolo Ruggero , Rodrigues Francisco Sandro Menezes , Ferraz Renato Ribeiro Nogueira , Neto Afonso Caricati
Published: October 2015

Introduction: Common variable immunodeficiency (CVID) is an immunological disorder characterized by defective antibody production. Objectives: To study the number, cell markers, activation surface molecules, lymproproliferative responde, cytokine production and apoptosis in PBMC. Methods: Thirty four patients with CVID selected by Division of Clinic Immunology and Allergy of Faculty of Medicine of University of São Paulo (FMUSP), Brazil were studied. Peripheral mononuclear blood cells (PBMC) of CVID patients and healthy individuals were evaluate to the expression of surface markers, activation molecules, lymphoproliferative response, cytokines synthesis and apoptosis. Results: In our work CVID patients showed decrease in T and B lymphocytes counts, CD25, CD69, CD40L and CD70 expression, and lower syntesis of IL-4 and IL-5. Furthermore, their lymphocytes are more susceptible to apoptosis following activation. Conclusion: The higher susceptibility to apoptosis may also be responsible for the decrease in the expression of activation molecules, cytokines and T and B circulating cells.
Resíduos plásticos e reciclagem: aspectos gerais e tecnologia
Authors: Zanin Maria , Mancini Sandro Donnini
Published: October 2015

A população do planeta, no início do século XXI, é estimada em 6,2 bilhões de habitantes (no início da civilização era de somente 200 milhões), que geram mais de um bilhão de toneladas de resíduos sólidos a cada ano, sendo cerca de 83 milhões de toneladas a parte brasileira. Nesse sentido, a ação de reciclar significa algo possível, viável, necessário e urgente. É isso que este livro tem por base.
Environmental changes in oxygen tension reveal ROS-dependent neurogenesis and regeneration in the adult newt brain
Authors: Hameed L Shahul , Berg Daniel A , Belnoue Laure , Jensen Lasse D , Cao Yihai , Simon András
Published: October 2015

Organisms need to adapt to the ecological constraints in their habitat. How specific processes reflect such adaptations are difficult to model experimentally. We tested whether environmental shifts in oxygen tension lead to events in the adult newt brain that share features with processes occurring during neuronal regeneration under normoxia. By experimental simulation of varying oxygen concentrations, we show that hypoxia followed by re-oxygenation lead to neuronal death and hallmarks of an injury response, including activation of neural stem cells ultimately leading to neurogenesis. Neural stem cells accumulate reactive oxygen species (ROS) during re-oxygenation and inhibition of ROS biosynthesis counteracts their proliferation as well as neurogenesis. Importantly, regeneration of dopamine neurons under normoxia also depends on ROS-production. These data demonstrate a role for ROS-production in neurogenesis in newts and suggest that this role may have been recruited to the capacity to replace lost neurons in the brain of an adult vertebrate.
Quality medical management of the geriatric population using practice guidelines, physician-managed home health services, and continuous quality-improvement management strategies
Authors: Reaves Lori A , Cavalieri Thomas A
Published: October 2015

One challenge confronting physicians in the 1990s is' the delivery of cost-effective quality healthcare to the elderly. Given current utilization, federal expenditures on Medicare and other federal healthcare programs are projected to increase to more than 6% of the gross national product by the year 2030. Physicians' practice habits will have an impact on the cost of caring for the nation's elderly. It is therefore essential for physicians to recognize their role in delivering quality geriatric care. First, they must be active and diligent in the pursuit of practice guidelines that support changes in the current standards of care. Second, physiciansshould consider alternative approaches to present practice patterns such as physician-managed home health services. Finally, physicians need to take a proactive approach to quality by supporting continuous quality improvement. The purpose of this review is to present some of the existing established practice guidelines, data to support the use of physician-managed home care as an alternative practice approach, and suggestions to incorporate the principles of continuous quality improvement to serve as one practice model that can be used by physicians to improve the quality of medical care given to America's elderly.
Specific cyclooxygenase-2 (COX-2) inhibitors
Authors: Rubin Bernard R
Published: October 2015

Nonsteroidal anti-inflammatory drugs (NSAIDs) are currently among the most widely prescribed drugs worldwide. Their therapeutic benefits and their side effects in the gastrointestinal tract and kidney, as well as in hemostasis, are of great importance in modem medicine. Within the past decade, new insights into how NSAIDs produce both their therapeutic benefits and their serious side effects have been discovered. It is now known that there are two forms of the cyclooxygenase (COX) enzyme that metabolize arachidonic acid into protstagladins. Drugs that specifically inhibit the COX-2 enzyme were formulated and put into clinical trials during the past 5 years. These drugs are now available to treat patients in the United States. Specific COX-2 inhibitors offer the benefit of being able to treat the pain and inflammation of arthritis with potentially little risk of serious gastrointestinal injury.
Diagnosis and treatment of severe dysplastic spondylolisthesis
Authors: Leone Louis D , Lamont David W
Published: October 2015

Spondylolisthesis, the anterior or posterior displacement of one vertebra on another, usually affects the lumbar region. Five percent of the population has one of the five classes of spondylolisthesis, which include dysplastic, isthmic, degenerative, traumatic, and pathologic spondylolisthesis. This article focuses on the dysplastic type, which makes up 14% to 21 % of all spondylolisthesis. Dysplastic spondylolisthesis usually causes no symptoms in children; pain usually begins in adolescence.The key to diagnosis is the appropriate use of radiography in the evaluation of low back pain. This report describes a case involving a 21-year-old woman presenting with back pain to the family physician. Also, it details how the diagnosis was achieved and evaluates conservative and aggressive treatment options.
Multifaceted interventions to decrease mortality in patients with severe sepsis/septic shock—a quality improvement project
Authors: Siontis Brittany , Elmer Jennifer , Dannielson Richard , Brown Catherine , Park John , Surani Salim , Ramar Kannan
Published: October 2015

Despite knowledge that EGDT improves outcomes in septic patients, staff education on EGDT and compliance with the CPOE order set has been variable. Based on results of a resident survey to identify barriers to decrease severe sepsis/septic shock mortality in the medical intensive care unit (MICU), multifaceted interventions such as educational interventions to improve awareness to the importance of early goal-directed therapy (EGDT), and the use of the Computerized Physician Order Entry (CPOE) order set, were implemented in July 2013. CPOE order set was established to improve compliance with the EGDT resuscitation bundle elements. Orders were reviewed and compared for patients admitted to the MICU with severe sepsis/septic shock in July and August 2013 (controls) and 2014 (following the intervention). Similarly, educational slide sets were used as interventions for residents before the start of their ICU rotations in July and August 2013. While CPOE order set compliance did not significantly improve (78% vs. 76%,p= 0.74), overall EGDT adherence improved from 43% to 68% (p= 0.0295). Although there was a trend toward improved mortality, this did not reach statistical significance. This study shows that education interventions can be used to increase awareness of severe sepsis/septic shock and improve overall EGDT adherence.
What do giant titanosaur dinosaurs and modern Australasian megapodes have in common?
Authors: Hechenleitner E. Martín , Grellet-Tinner Gerald , Fiorelli Lucas E.
Published: October 2015

Titanosauria is a globally distributed clade of sometimes extremely large Mesozoic herbivorous sauropod dinosaurs. On the basis of current evidence these giant dinosaurs seem to have reproduced in specific and localized nesting sites. However, no investigations have been performed to understand the possible ecological and geological biases that acted for the selection of these nesting sites worldwide. In this study, observations were performed on the best-known Cretaceous nesting sites around the world. Our observations strongly suggest their eggs were incubated with environmental sources of heat, in burial conditions. Taking into account the clutch composition and geometry, the nature and properties of the sediments, the eggshells’ structures and conductance, it would appear that titanosaurs adopted nesting behaviors comparable to the modern Australasian megapodes, using burrow-nesting in diverse media and mound-building strategies.
ProCS15: a DFT-based chemical shift predictor for backbone and Cβatoms in proteins
Authors: Larsen Anders S. , Bratholm Lars A. , Christensen Anders S. , Channir Maher , Jensen Jan H.
Published: October 2015

We present ProCS15: a program that computes the isotropic chemical shielding values of backbone and Cβatoms given a protein structure in less than a second. ProCS15 is based on around 2.35 million OPBE/6-31G(d,p)//PM6 calculations on tripeptides and small structural models of hydrogen-bonding. The ProCS15-predicted chemical shielding values are compared to experimentally measured chemical shifts for Ubiquitin and the third IgG-binding domain of Protein G through linear regression and yield RMSD values of up to 2.2, 0.7, and 4.8 ppm for carbon, hydrogen, and nitrogen atoms. These RMSD values are very similar to corresponding RMSD values computed using OPBE/6-31G(d,p) for the entire structure for each proteins. These maximum RMSD values can be reduced by using NMR-derived structural ensembles of Ubiquitin. For example, for the largest ensemble the largest RMSD values are 1.7, 0.5, and 3.5 ppm for carbon, hydrogen, and nitrogen. The corresponding RMSD values predicted by several empirical chemical shift predictors range between 0.7–1.1, 0.2–0.4, and 1.8–2.8 ppm for carbon, hydrogen, and nitrogen atoms, respectively.
Modeling stream temperature in the Anthropocene: An earth system modeling approach
Authors: Li Hong‐Yi , Ruby Leung L. , Tesfa Teklu , Voisin Nathalie , Hejazi Mohamad , Liu Lu , Liu Ying , Rice Jennie , Wu Huan , Yang Xiaofan
Published: October 2015

A new large‐scale stream temperature model has been developed within the Community Earth System Model (CESM) framework. The model is coupled with the Model for Scale Adaptive River Transport (MOSART) that represents river routing and a water management model (WM) that represents the effects of reservoir operations and water withdrawals on flow regulation. The coupled models allow the impacts of reservoir operations and withdrawals on stream temperature to be explicitly represented in a physically based and consistent way. The models have been applied to the Contiguous United States driven by observed meteorological forcing. Including water management in the models improves the agreement between the simulated and observed streamflow at a large number of stream gauge stations. It is then shown that the model is capable of reproducing stream temperature spatiotemporal variation satisfactorily by comparing against the observed data from over 320 USGS stations. Both climate and water management are found to have important influence on the spatiotemporal patterns of stream temperature. Furthermore, it is quantitatively estimated that reservoir operation could cool down stream temperature in the summer low‐flow season (August–October) by as much as 1∼2°C due to enhanced low‐flow conditions, which have important implications to aquatic ecosystems. Sensitivity of the simulated stream temperature to input data and reservoir operation rules used in the WM model motivates future directions to address some limitations in the current modeling framework.
Mixed Methods Research
Authors: Bartholomew Theodore T.
Published: October 2015

Mixed methods as an avenue of inquiry has developed into a field of its own, distinguishable from quantitative and qualitative analyses. Because this approach to research reflects a pragmatic means of accruing culturally sensitive data from multiple lenses in a single study, it may offer an important opportunity for cross‐cultural and cultural psychologists. Conducting mixed methods studies allows cultural researchers to simultaneously gather broader, culturally valid quantitative data and provide additional meaning through deep, qualitative understanding. This task is not simple, however, as it requires an understanding of qualitative and quantitative methods as well as the means of integrating data into a single study. Despite the potential difficulties in intentionally combining methods in a single study, mixed methods offers cross‐cultural and cultural psychologists the opportunity to gather multiple types of data, draw comparisons, and better understand culturally‐relevant phenomena.
Rheumatoid Arthritis and Mortality Among Women During 36 Years of Prospective Follow‐Up: Results From the Nurses’ Health Study
Authors: Sparks Jeffrey A. , Chang Shun‐Chiao , Liao Katherine P. , Lu Bing , Fine Alexander R. , Solomon Daniel H. , Costenbader Karen H. , Karlson Elizabeth W.
Published: October 2015

Objective

To evaluate rheumatoid arthritis (RA) and mortality risk among women followed prospectively in the Nurses’ Health Study (NHS).

Methods

We analyzed 119,209 women in the NHS who reported no connective tissue disease at enrollment in 1976. Comorbidity and lifestyle data were collected through biennial questionnaires. Incident RA cases were validated by medical records review. Cause of death was determined by death certificate and medical records review. Cox regression models estimated hazard ratios (HRs) and 95% confidence intervals (95% CIs) for all‐cause, cardiovascular disease (CVD), cancer, and respiratory disease mortality for women with RA compared to those without RA.

Results

We validated 964 incident RA cases and identified 28,808 deaths during 36 years of prospective follow‐up. Of 307 deaths among women with RA, 80 (26%) were from cancer, 70 (23%) were from CVD, and 44 (14%) were from respiratory causes. Women with RA had increased total mortality (HR 1.40, 95% CI 1.25–1.57) compared to those without RA, independent of mortality risk factors, including smoking. RA was associated with significantly increased respiratory disease mortality (HR 2.06, 95% CI 1.51–2.80) and cardiovascular disease mortality (HR 1.45, 95% CI 1.14–1.83), but not cancer mortality (HR 0.93, 95% CI 0.74–1.15). For women with seropositive RA, respiratory disease mortality was nearly 3‐fold higher than among non‐RA women (HR 2.67, 95% CI 1.89–3.77).

Conclusion

Women with RA had significantly increased mortality compared to those without RA. Respiratory disease and cardiovascular disease mortality were both significantly elevated for women with RA. The nearly 3‐fold increased relative risk of respiratory disease mortality was observed only for those with seropositive RA.
Role of Osteoarthritis, Comorbidity, and Pain in Determining Functional Limitations in Older Populations: European Project on Osteoarthritis
Authors: Zambon Sabina , Siviero Paola , Denkinger Michael , Limongi Federica , Victoria Castell Maria , van der Pas Suzan , Otero Ángel , Edwards Mark H. , Peter Richard , Pedersen Nancy L. , Sánchez‐Martinez Mercedes , Dennison Elaine M. , Gesmundo Antonella , Schaap Laura A. , Deeg Dorly J. H. , van Schoor Natasja M. , Maggi Stefania ,   for the Eposa Research Group
Published: October 2015

Objective

To evaluate the role of comorbidity and pain in the association between hip/knee osteoarthritis (OA) with self‐reported as well as performance‐based functional limitations in a general elderly population.

Methods

We analyzed the data of 2,942 individuals, ages between 65 and 85 years, who participated in the European Project on Osteoarthritis, which was made up of 6 European cohorts (from Germany, Italy, The Netherlands, Spain, Sweden, and the UK). Outcomes included self‐reported physical function measured by the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and the participants’ performance‐based physical function was evaluated using the walking test.

Results

While comorbidity did not affect the significant association between hip/knee OA and physical function limitations found in the participants, pain reduced the effect of OA on self‐reported physical function, and it cancelled the effect of OA on the walking test. Obesity, anxiety, depression, and cardiovascular diseases were associated with the worst WOMAC scores. Obesity, cognitive impairment, depression, peripheral artery disease, and stroke were associated with the worst walking times.

Conclusion

These findings demonstrate that while comorbidity is strongly and independently associated with functional limitations, it does not affect the OA–physical function association. Hip/knee OA is associated with self‐reported impairment in physical function, which was only partially mediated by pain. Its association with physical function, as evaluated by the walking test, was instead completely mediated by pain.
Participation in Clinical Research Registries: A Focus Group Study Examining Views From Patients With Arthritis and Other Chronic Illnesses
Authors: Lee Sara B. , Zak Agnes , Iversen Maura D. , Polletta Valerie L. , Shadick Nancy A. , Solomon Daniel H.
Published: October 2015

Objective

Patient registries have contributed substantially to progress in clinical research in rheumatic diseases. However, not much is known about how to optimize the patient experience in such registries. We assessed patient views, motivations, and potential barriers towards participation in registry research to better understand how registries can be improved to maximize patient engagement.

Methods

Focus groups were held with 23 patients (mean ± SD age 59 ± 13 years) from the Boston area and led by a bilingual moderator trained in focus group methodology, using a semistructured moderator guide. Three separate focus groups were conducted to thematic saturation: patients with rheumatoid arthritis (RA) who had registry experience, patients with any chronic illness, and Spanish‐speaking patients with RA or osteoarthritis. Patients in the latter 2 groups had no prior registry experience. Focus groups were audiotaped and transcribed. Four researchers independently analyzed transcripts using open data coding to identify themes. A normative group process was used to consolidate and refine themes.

Results

Seven major themes were identified, including personalization/convenience of data collection, trust and confidentiality, camaraderie, learning about yourself and your disease, altruism, material motivators, and capturing mental health and other elements of the lived experience. We observed distinct differences in the discussion content of the Spanish‐speaking patients compared to the English‐speaking patients.

Conclusion

This study identified patient attitudes towards registry research among those with and without prior experience in a registry. The results provide insight into strategies for registry design to maximize patient engagement, which can lead to more robust registry data.
Proline‐Catalyzed Cyclization Reaction for the Synthesis of Naphthostyrils: Application to the Total Synthesis of Prioline
Authors: Park Kyeong‐Yong , Song Ha‐Jeong , Heo Jung‐Nyoung
Published: October 2015

A new method for the synthesis of naphthostyrils is described. In this method, a sequential Stille coupling and proline‐catalyzed cyclization procedure is employed for the reaction of 4‐bromooxindoles and β‐tributylstannyl‐α,β‐unsaturated ketones. The utility of this methodology is demonstrated in the first total synthesis of prioline from a simple 2‐isopropylphenol.

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Helical Channel Mesoporous Materials with Embedded Magnetic Iron Nanoparticles: Chiral Recognition and Implications in Asymmetric Olefin Epoxidation
Authors: Fernandes Cristina I. , Stenning Gavin B. G. , Taylor James D. , Nunes Carla D. , D. Vaz Pedro
Published: October 2015

In this work a mesoporous nanocomposite material comprising helical chiral channels and with embedded magnetic iron oxide nanoparticles in its Si‐based MCM‐41 type framework was synthesized. Afterwards, a bipyridine derivative was grafted to the inner surface used as ligand to coordinate a molybdenum(II) precursor complex. The Mo loading was found to be 2.42 wt% Mo, corresponding to 0.26 mmolMo g−1. The successful preparation of this helical mesoporous material was evidenced by an extensive characterization process using powder XRD, SEM/TEM analysis, FT‐IR and Raman spectroscopies, TGA analysis and also by SQUID measurements. Selective adsorption of enantiopure D‐ and L‐phenylalanine shows that the material has a preference for the D‐ over the L‐ enantiomer. This provides evidence that the channels are chiral (although the particles are not) and that it is useful for chiral recognition applications. It also sets the explanation to the good results achieved in the selective epoxidation of olefins. The resulting material was tested as catalytic precursor in the epoxidation of cis‐cyclooctene, styrene, R‐(+)‐limonene and trans‐hex‐2‐en‐1‐ol, using tert‐butyl hydroperoxide (tbhp) as oxygen source. The catalytic studies show that the synthesized material yields selectively the desired epoxides of the tested substrates with very good results, especially at higher temperatures and using toluene as solvent. The major achievement of the catalyst was an outstanding stereocontrol of the reaction products imposed by the confined space of the helical chiral channels. Therefore these materials offer an important contribution to asymmetric catalysis and to fields where chiral recognition is a relevant concept.

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Indium(III)‐Catalyzed Cyclization of Aromatic 5‐Enynamides: Facile Synthesis of 2‐Aminonaphthalenes, 2‐Amino‐1H‐indenes, and 2,3‐Dihydro‐1H‐indeno[2,1‐b]pyridines
Authors: Yeh Ming‐Chang P. , Liang Chia‐Jung , Chen Hsiao‐Feng , Weng Yu‐Ting
Published: October 2015

Indium(III)‐catalyzed cyclization reactions of aromatic 5‐enynamides were studied. Indium triflate enabled the efficient synthesis of 2‐aminonaphthalenes and 2‐amino‐1H‐indenes from aromatic N‐methyl‐N‐tosyl‐ynamides bearing an ortho‐vinyl and ‐isobutenyl group, respectively. The aromatic N‐3‐arylpropargylynamides bearing an ortho‐gem‐dihalovinyl subunit underwent a tandem cyclization/carbobromination reaction in the presence of indium tribromide to provide the dibrominated 2,3‐dihydro‐1H‐indeno[2,1‐b]pyridine derivatives in good yields.

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Regio‐ and Enantioselective Allylation of Phenols via Decarboxylative Allylic Etherification of Allyl Aryl Carbonates Catalyzed by (Cyclopentadienyl)ruthenium(II) Complexes and Pyridine‐Hydrazone Ligands
Authors: Egger Léo , Tortoreto Cecilia , Achard Thierry , Monge David , Ros Abel , Fernández Rosario , Lassaletta José M. , Lacour Jérôme
Published: October 2015

(Cyclopentadienyl)tris(acetonitrile)ruthenium hexafluorophosphate [CpRu(CH3CN)3][PF6] in combination with pyridine‐hydrazone ligands efficiently catalyzes the asymmetric decarboxylative allylic rearrangement of allyl aryl carbonates. Formation of CO bonds with high regio‐ and enantioselectivity ratios (up to 95:5 and 98% ee) is obtained. Good stereocontrol of the pseudotetrahedral geometry of the CpRu moiety is achieved by the hydrazone ligand and its “electron‐poor” nature is evidenced through the epimerization of the hexacoordinated TRISPHAT‐N anion.

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Synthesis of Polysubstituted Imidazoles and Pyridines via Samarium(III) Triflate‐Catalyzed [2+2+1] and [4+2] Annulations of Unactivated Aromatic Alkenes with Azides
Authors: Wang Yingchun , Li Jiuling , He Yan , Xie Yuyang , Wang Hengshan , Pan Yingming
Published: October 2015

Samarium(III) triflate‐catalyzed [2+2+1] and [4+2] annulations have been identified for the preparation of fully substituted imidazoles and 2,3,5‐trisubstituted pyridines from the readily available unactivated aromatic alkenes and azidomethyl aromatics. These reactions proceeded smoothly with one‐ or two‐nitrogen synthons to afford a range of two types of skeletally distinct N‐heterocycles in good yields. Mechanistic studies revealed that the annulation reaction proceed via an initial samarium(III) triflate‐induced 1,3 dipolar cycloaddition followed by 1,2‐migration to form an enamine as the key intermediate. Density functional theory (DFT) calculations suggested that the selectivity of 1,2‐H and 1,2‐aryl migration depends on the structure of the alkenes.

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An Approach to the Efficient Syntheses of Chiral Phosphino‐ Carboxylic Acid Esters
Authors: Chew Renta Jonathan , Sepp Kristel , Li Bin‐Bin , Li Yongxin , Zhu Peng‐Cheng , Tan Nguan Soon , Leung Pak‐Hing
Published: October 2015

The catalytic hydrophosphination reaction is one of the most sustainable chemical transformations today. Here, the palladium‐catalyzed asymmetric PH addition of diarylphosphines with N‐enoylbenzotriazoles and analogues is described. Chiral phosphine products are obtained in 100% atom economy and without cumbersome protection–deprotection manipulations. The obtained products can be subsequently transformed to bear various functionalities, including phosphino‐carboxylic esters which play critical roles in catalysis and as synthetic aids. Anti‐tumour activities of the corresponding gold‐phosphine complexes have been explored, contributing to existing chemotherapeutic research in cancer treatment.

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Boron Trifluoride⋅Diethyl Ether‐Catalyzed Etherification of Alcohols: A Metal‐Free Pathway to Diphenylmethyl Ethers
Authors: Li Jiaqiang , Zhang Xiaohui , Shen Hang , Liu Qing , Pan Jing , Hu Wen , Xiong Yan , Chen Changguo
Published: October 2015

A novel boron trifluoride⋅diethyl ether (BF3⋅OEt2)‐catalyzed etherification procedure has been developed in which primary and secondary alcohols are easily converted into diphenylmethyl ethers with yields of up to 99%.

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Metallkatalysierte β‐Funktionalisierung von Michael‐Akzeptoren über reduktive Radikaladditionen
Authors: Streuff Jan , Gansäuer Andreas
Published: October 2015

Übergangsmetallkatalysierte Radikalreaktionen gewinnen in der modernen organischen Chemie zunehmend an Bedeutung. Sie bieten faszinierende und unkonventionelle Möglichkeiten zur Verknüpfung von Molekülfragmenten, die oftmals komplementär zu klassischen Methoden sind. Insbesondere reduktive Radikaladditionen an α,β‐ungesättigte Verbindungen sind aufgrund ihrer breiten Anwendbarkeit in der Synthese von besonderem Interesse. Dieser Kurzaufsatz betrachtet die auf diesem Gebiet kürzlich erzielten Fortschritte und stellt sie in kritischen Kontext zu früheren Arbeiten, die den Grundstein für die heutigen Entwicklungen gelegt haben.
Direct Observation of an Anomalous Spinel‐to‐Layered Phase Transition Mediated by Crystal Water Intercalation
Authors: Kim Sangryun , Nam Kwan Woo , Lee Soyeon , Cho Woosuk , Kim Joo‐Seong , Kim Byung Gon , Oshima Yoshifumi , Kim Ju‐Sik , Doo Seok‐Gwang , Chang Hyuk , Aurbach Doron , Choi Jang Wook
Published: October 2015

The phase transition of layered manganese oxides to spinel phases is a well‐known phenomenon in rechargeable batteries and is the main origin of the capacity fading in these materials. This spontaneous phase transition is associated with the intrinsic properties of manganese, such as its size, preferred crystal positions, and reaction characteristics, and it is therefore very difficult to avoid. The introduction of crystal water by an electrochemical process enables the inverse phase transition from spinel to a layered Birnessite structure. Scanning transmission electron microscopy can be used to directly visualize the rearrangement of lattice atoms, the simultaneous insertion of crystal water, the formation of a transient structure at the phase boundary, and layer‐by‐layer progression of the phase transition from the edge. This research indicates that crystal water intercalation can reverse phase transformation with thermodynamically favored directionality.
Electrocatalytic Production of C3‐C4 Compounds by Conversion of CO2 on a Chloride‐Induced Bi‐Phasic Cu2O‐Cu Catalyst
Authors: Lee Seunghwa , Kim Dahee , Lee Jaeyoung
Published: October 2015

Electrocatalytic conversion of carbon dioxide (CO2) has recently received considerable attention as one of the most feasible CO2 utilization techniques. In particular, copper and copper‐derived catalysts have exhibited the ability to produce a number of organic molecules from CO2. Herein, we report a chloride (Cl)‐induced bi‐phasic cuprous oxide (Cu2O) and metallic copper (Cu) electrode (Cu2OCl) as an efficient catalyst for the formation of high‐carbon organic molecules by CO2 conversion, and identify the origin of electroselectivity toward the formation of high‐carbon organic compounds. The Cu2OCl electrocatalyst results in the preferential formation of multi‐carbon fuels, including n‐propanol and n‐butane C3–C4 compounds. We propose that the remarkable electrocatalytic conversion behavior is due to the favorable affinity between the reaction intermediates and the catalytic surface.
Beyond Dehydrocoupling: Group 2 Mediated Boron–Nitrogen Desilacoupling
Authors: Liptrot David J. , Arrowsmith Merle , Colebatch Annie L. , Hadlington Terrance J. , Hill Michael S. , Kociok‐Köhn Gabriele , Mahon Mary F.
Published: October 2015

The alkaline‐earth element bis(trimethylsilyl)amides, [Ae{N(SiMe3)2}2(thf)2] [Ae=Mg, Ca, Sr], are effective precatalysts for boron–nitrogen bond formation through the desilacoupling of amines, RR′NH (R=alkyl, aryl; R′=H, alkyl, aryl), and pinBSiMe2Ph. This reactivity also yields a stoichiometric quantity of Me2PhSiH and provides the first example of a catalytic main‐group element–element coupling that is not dependent on the concurrent elimination of H2.
Synthesis and Design of Aggregation‐Induced Emission Surfactants: Direct Observation of Micelle Transitions and Microemulsion Droplets
Authors: Guan Weijiang , Zhou Wenjuan , Lu Chao , Tang Ben Zhong
Published: October 2015

The direct visualization of micelle transitions is a long‐standing challenge owing to the intractable aggregation‐caused quenching of light emission in the micelle solution. Herein, we report the synthesis of a surfactant with a tetraphenylethene (TPE) core and aggregation‐induced emission (AIE) characteristics. The transition processes of surfactant micelles and the microemulsion droplets (MEDs) formed by the surfactant with a TPE core were clearly visualized by a high‐contrast fluorescence imaging method. The fluorescence intensity of the MEDs decreased as the size of MEDs increased as a result of weakening of the restriction of intramolecular rotation (RIR). The results of this study deepen our understanding of micelle‐transition processes and provide solid evidence in favor of the hypothesis that the AIE phenomenon has its origin in the RIR of fluorophores in the aggregate state.
Three Aromatic Residues are Required for Electron Transfer during Iron Mineralization in Bacterioferritin
Authors: Bradley Justin M. , Svistunenko Dimitri A. , Lawson Tamara L. , Hemmings Andrew M. , Moore Geoffrey R. , Le Brun Nick E.
Published: October 2015

Ferritins are iron storage proteins that overcome the problems of toxicity and poor bioavailability of iron by catalyzing iron oxidation and mineralization through the activity of a diiron ferroxidase site. Unlike in other ferritins, the oxidized di‐Fe3+ site of Escherichia coli bacterioferritin (EcBFR) is stable and therefore does not function as a conduit for the transfer of Fe3+ into the storage cavity, but instead acts as a true catalytic cofactor that cycles its oxidation state while driving Fe2+ oxidation in the cavity. Herein, we demonstrate that EcBFR mineralization depends on three aromatic residues near the diiron site, Tyr25, Tyr58, and Trp133, and that a transient radical is formed on Tyr25. The data indicate that the aromatic residues, together with a previously identified inner surface iron site, promote mineralization by ensuring the simultaneous delivery of two electrons, derived from Fe2+ oxidation in the BFR cavity, to the di‐ferric catalytic site for safe reduction of O2.
Development of a Sensitive Bioluminogenic Probe for Imaging Highly Reactive Oxygen Species in Living Rats
Authors: Kojima Ryosuke , Takakura Hideo , Kamiya Mako , Kobayashi Eiji , Komatsu Toru , Ueno Tasuku , Terai Takuya , Hanaoka Kenjiro , Nagano Tetsuo , Urano Yasuteru
Published: October 2015

A sensitive bioluminogenic probe for highly reactive oxygen species (hROS), SO3H‐APL, was developed based on the concept of dual control of bioluminescence emission by means of bioluminescent enzyme‐induced electron transfer (BioLeT) and modulation of cell‐membrane permeability. This probe enables non‐invasive visualization of physiologically relevant amounts of hROS generated deep inside the body of living rats for the first time. It is expected to serve as a practical analytical tool for investigating a wide range of biological functions of hROS in vivo. The design concept should be applicable to other in vivo bioluminogenic probes.
FeCl3‐Mediated Oxidative Spirocyclization of Difluorenylidene Diarylethanes Leading to Dispiro[fluorene‐9,5′‐indeno[2,1‐a]indene‐10′,9′′‐fluorene]s
Authors: Zhao Jian , Xu Zhanqiang , Oniwa Kazuaki , Asao Naoki , Yamamoto Yoshinori , Jin Tienan
Published: October 2015

A novel FeCl3‐mediated oxidative spirocyclization for construction of a new class of di‐spirolinked π‐conjugated molecules, dispiro[fluorene‐9,5′‐indeno[2,1‐a]indene‐10′,9′′‐fluorene]s (DSFIIFs), has been reported. The combination of FeCl3 with FeO(OH) triggered an unprecedented double one‐electron oxidation of difluorenylidene diarylethanes to afford the corresponding dispirocycles in high yields. The highest fluorescence quantum yield was up to 0.94 in solution. This protocol is also applicable to the synthesis of the non‐spirolinked dihydroindenoindenes.
Überoxidation als Schlüsselschritt im Mechanismus der MoCl5‐ vermittelten dehydrierenden Arenkupplung
Authors: Schubert Moritz , Franzmann Peter , Wünsche von Leupoldt Anica , Koszinowski Konrad , Heinze Katja , Waldvogel Siegfried R.
Published: October 2015

Molybdänpentachlorid ist ein effizientes Reagens für die dehydrierende Kupplung von Arenen. Wegen der hohen Reaktionsgeschwindigkeit bei der Umsetzung mit MoCl5 wird eine Reihe von labilen Molekülbereichen in dieser Transformation toleriert. Der mechanistische Verlauf der Reaktion wurde bislang sehr kontrovers diskutiert, auch wenn vor kurzem Hinweise gefunden wurden, dass ein Ein‐Elektronen‐Transfer die Umsetzung einleitet. Hier kann aus einer kombinierten Studie in Form von systematischen Syntheseversuchen, elektrochemischen Messungen, EPR‐Spektroskopie, DFT‐Rechnungen und Massenspektrometrie eine hochkonsistente mechanistische Vorstellung abgeleitet werden. MoCl5 fungiert als Ein‐Elektronen‐Oxidationsmittel in der Abwesenheit von TiCl4 und als Zwei‐Elektronen‐Oxidationsmittel in Gegenwart von TiCl4. In beiden Fällen führt es zu einem überoxidierten Intermediat, das die Zielstruktur vor Nebenreaktionen schützt. Im Zuge der wässrigen Aufarbeitung wirkt der Reagensabfall (MoIII/IV‐Verbindungen) als Reduktionsmittel und liefert das gewünschte organische C‐C‐Kupplungsprodukt.
Silver‐Catalyzed Amidiniumation of Alkynes: Isolation of a Silver Intermediate, Synthesis of Enamine Amido Carbene Precursors, and an Unprecedented Umpolung of Propiolamide
Authors: Lv Shichang , Wang Jiwei , Zhang Caiyun , Xu Sheng , Shi Min , Zhang Jun
Published: October 2015

A silver‐catalyzed amidiniumation of N‐propiolic formamidines for the synthesis of novel enamine amido carbene precursors is reported. Isolation of a first silver intermediate in silver‐catalyzed amidiniumation of alkynes and other organogold intermediates supports our proposed mechanisms. Several control experiments reveal the unexpected effects of both HOTf and substrate substituents on the choice of either a π or σ,π silver activation mode and the cyclization fashion. Bis(hydroxyimidazol)ium salts were obtained through an unprecedented umpolung of propiolamides. The byproduct Ag2O as either an oxidant or silver source promotes the syntheses of N‐heterocyclic carbene (NHC) precursors or Ag/NHC complexes.
Direct Modulation of Small GTPase Activity and Function
Authors: Cromm Philipp M. , Spiegel Jochen , Grossmann Tom N. , Waldmann Herbert
Published: October 2015

Small GTPases are a family of GDP‐/GTP‐binding proteins that serve as biomolecular switches inside cells to control a variety of essential cellular processes. Aberrant function and regulation of small GTPases is associated with a variety of human diseases, thus rendering these proteins highly interesting targets in drug discovery. However, this class of proteins has been considered “undruggable”, as intensive decade‐long efforts did not yield clinically relevant direct modulators of small GTPases. Recently, the targeting of small GTPases has gained fresh impetus through the discovery of novel transient cavities on the protein surfaces and the application of new targeting strategies. Besides Ras proteins, other small GTPases have attracted increased attention since improved biological insight in combination with novel targeting strategies identified them as promising targets in drug discovery. This Review gives an overview of relevant aspects of the superfamily of small GTPases and summarizes recent progress and perspectives for the direct modulation of these challenging targets.
Nucleobase‐Modified PNA Suppresses Translation by Forming a Triple Helix with a Hairpin Structure in mRNA In Vitro and in Cells
Authors: Endoh Tamaki , Hnedzko Dziyana , Rozners Eriks , Sugimoto Naoki
Published: October 2015

Compounds that bind specifically to double‐stranded regions of RNA have potential as regulators of structure‐based RNA function; however, sequence‐selective recognition of double‐stranded RNA is challenging. The modification of peptide nucleic acid (PNA) with unnatural nucleobases enables the formation of PNA–RNA triplexes. Herein, we demonstrate that a 9‐mer PNA forms a sequence‐specific PNA–RNA triplex with a dissociation constant of less than 1 nm at physiological pH. The triplex formed within the 5′ untranslated region of an mRNA reduces the protein expression levels both in vitro and in cells. A single triplet mismatch destabilizes the complex, and in this case, no translation suppression is observed. The triplex‐forming PNAs are unique and potent compounds that hold promise as inhibitors of cellular functions that are controlled by double‐stranded RNAs, such as RNA interference, RNA editing, and RNA localization mediated by protein–RNA interactions.
Untangling a Repetitive Amyloid Sequence: Correlating Biofilm‐Derived and Segmentally Labeled Curli Fimbriae by Solid‐State NMR Spectroscopy
Authors: Schubeis Tobias , Yuan Puwei , Ahmed Mumdooh , Nagaraj Madhu , van Rossum Barth‐Jan , Ritter Christiane
Published: October 2015

Curli are functional bacterial amyloids produced by an intricate biogenesis machinery. Insights into their folding and regulation can advance our understanding of amyloidogenesis. However, gaining detailed structural information of amyloids, and their tendency for structural polymorphisms, remains challenging. Herein we compare high‐quality solid‐state NMR spectra from biofilm‐derived and recombinantly produced curli and provide evidence that they adopt a similar, well‐defined β‐solenoid arrangement. Curli subunits consist of five sequence repeats, resulting in severe spectral overlap. Using segmental isotope labeling, we obtained the unambiguous sequence‐specific resonance assignments and secondary structure of one repeat, and demonstrate that all repeats are most likely structurally equivalent.
Cobalt‐Catalyzed Alkylation of Aromatic Amines by Alcohols
Authors: Rösler Sina , Ertl Michael , Irrgang Torsten , Kempe Rhett
Published: October 2015

The implementation of inexpensive, Earth‐abundant metals in typical noble‐metal‐mediated chemistry is a major goal in homogeneous catalysis. A sustainable or green reaction that has received a lot of attention in recent years and is preferentially catalyzed by Ir or Ru complexes is the alkylation of amines by alcohols. It is based on the borrowing hydrogen or hydrogen autotransfer concept. Herein, we report on the Co‐catalyzed alkylation of aromatic amines by alcohols. The reaction proceeds under mild conditions, and selectively generates monoalkylated amines. The observed selectivity allows the synthesis of unsymmetrically substituted diamines. A novel Co complex stabilized by a PN5P ligand catalyzes the reactions most efficiently.
An Enantioselective Total Synthesis of (−)‐Isoschizogamine
Authors: Xu Zhengren , Bao Xu , Wang Qian , Zhu Jieping
Published: October 2015

A concise enantioselective total synthesis of (−)‐isoschizogamine, a complex bridged polycyclic monoterpene indole alkaloid, was accomplished. N‐Alkylation of an enantio‐enriched imine with an alkyl iodide afforded an iminium salt, which, upon heating by microwave irradiation in the presence of pivalic acid, was converted into the hexacyclic structure of natural product by a complex but ordered domino sequence. The one‐pot process leading to the formation of one CC bond and three CN bonds created three rings and three contiguous stereogenic centers with complete control of both the relative and absolute stereochemistry.