bluuebunny/crossref_metadata_2025 huggingface dataset:
Modular Footbridges of Guadua Angustifolia Kunth
Authors: Lamus Báez Fabián Augusto , Urazán Bonells Carlos Felipe , Andrade Pardo Sofía
Published: October 2015

In South America, especially in the Andean region, many communities are isolated and their development is limited due to the difficulties in communicating with urban areas, because the lack of adequate road infrastructure. Most of this problem is due to economic issues and lack of attention from governments. Moreover, the Guaduaangustifolia Kunth (Guadua-a.) is a bamboo that grows in most of the Americas. This material has a resistance – weight ratio similar to structural steel also presenting additional benefits such as soil stabilization, flow regulation, and a high CO2 fixation rate to the ground. In addition the Guadua-a. growth cycle spans from 3 to 5 years. All of these makes the Guadua-a. in highly renewable material. This paper presents an alternative for the construction of Guadua-a. structural modules for pedestrian bridges, as a solution to the lack of infrastructure in village roads and even in suburban areas. In the proposed model, the bridge would be built by the community in a short time, taking advantage of existing Guadua-a. in the area, and establishing an industrialized cultivation of it, to enable them to have enough material for maintenance and replacement of sections as necessary. A numerical structural analysis was performed to determine the maximum possible span under load specifications from Colombian bridge building code. The results shows that a bridge up to 21m of span can be constructed using the module. The span can be increased drastically when the module is combined with wire-cable or an arc shaped configuration, however, the module was assessed to be used in straight truss bridges because this setting carries the largest loads on the elements. Real scale load tests were conducted on a full scale physical model of the module, the structural elements and the connection between the modules.
Cover System for Roofs Manufactured with Recycled Polyethylene and Rubber
Authors: Gaggino Rosana , Positieri Maria , Kreiker Jerónimo , Sanchez Amono Maria Paz , Arguello Ricardo , Baronetto Juan Carlos
Published: October 2015

The intense waste generation moved by the urban and industrial activity and the wasteful consumption of natural resources, encourage the development of new technologies for the utilization of wastes and its reuse in new industrial processes, which decreases the environmental pollution and the removal of virgin materials. In this sense we work in the development of new materials and components from urban and industrial waste prepared by different techniques and with various applications.We work on the development of a composite material made with recycled rubber from tires out of use (NFU) and recycled polyethylene, linked through the fusion of the plastic and the subsequent pressing of the material. In this article we present the partial results obtained in the physical and mechanical testing of the roof tiles, and the burning behavior of the components manufactured with flame retardants additives available in the market, to comply with the regulations in order to use these housing components. These components have as main advantages the high resistance to flexion and the hard impact, low thermal conductivity, and low water absorption by immersion in water. Despite the fact that the components do not meet all the points of the reference Norm in regard to its behavior when exposed to fire, further amendments in the formulation and the manufacture process have shown interesting results, with which roof tiles could comply with the regulation for the use proposed.We developed a sustainable covering system for roof using two types of wastes in great abundance in all urban sites, which involve a simple manufacture process. Besides, due to its high flexibility and resistance to impact hard is presented as a good constructive alternative for housing covering in areas affected by the fall of hail or by the risk of blowing up and deterioration by strong winds.
Mechanical Behavior of Reinforced Clayey Soil with Fine Crushed Polyethylene Terephthalate
Authors: Martínez Ingrid Milena Reyes , Louzada Nathalia dos Santos Lopes , Repsold Lucas Mendes , Casagrande Michéle D.T.
Published: October 2015

Currently a lot of bottles of polyethylene terephthalate (PET) are discarded into the environment. In order to reduce the disposal of this polymer in nature, this study aims to evaluate the mechanical behavior of a clayey soil mixed with fine crushed PET. The potential use of this waste material in geotechnical applications may ultimately reduce the problem of improper disposal and improve the strength and deformation characteristics of the soil. This paper presents an experimental study to evaluate the mechanical behavior of pure soil and mixtures with different contents of PET waste by triaxial tests, in order to obtain the strength parameters of the Soil-PET mixtures. The clayey soil used was mixed with 10 and 20 percent of fine crushed PET by dry weight. Characterization tests such as grain size, Atterberg limits and compaction test were performed on the soil-PET mixtures. Triaxial tests at confining stresses of 50, 150 and 300 kPa were done on the soil and mixtures. The results show that the soil strength parameters are influenced by the addition of the fine crushed PET, thus improving characteristics such as friction angle and cohesion of the Soil-PET mixtures. This improvement also depends on the confining level which the samples were submitted. These mixtures may be used in pavement and other geotechnical works, so this paper proposes to contribute to a better understanding and interpretation of the behavior of reinforced soil with waste PET.
A Binder from Alkali Activation of FCC Waste: Use in Roof Tiles Fabrication
Authors: Mas María Antonia , Tashima Mauro M. , Payá J. , Borrachero M.V. , Soriano Lourdes , Monzó J.M.
Published: October 2015

Nowadays, scientific community is looking for alternatives to reduce the problem of CO2emissions, making more sustainable binders and reusing wastes from other industries.In this line, the technology of geopolymers was born, in which, binders based on alkali-activation can be produced entirely or almost entirely from waste materials. In alkali-activation a source of aluminosilicate is dissolved by a highly alkaline solution previous to precipitation reactions that form a gel binder.The use of alumino-silicate minerals such as metakaolin, blast furnace slag and fly ash to produce alkali-activated cements has been extensively studied and it’s increasing the interest in investigating the suitability of using other materials. Different wastes containing silica and alumina, such as hydrated-carbonated cement, glass, fluid catalytic cracking catalyst residues (FCC) have been activated.The aim of this study is to verify if the use of geopolymers is compatible with the manufacturing technology of typical building elements, in this case roof tiles.Mechanical properties of mortars and roof tiles using as source of aluminosilicates FCC have been studied, with different mixtures and variating the proportions of NaOH and waterglass.Compressive strength development was evaluated in mortars cured at 20oC for 7 and 28 days and flexural strength, impermeability and impact resistance were evaluated in roof tiles. The results obtained demonstrated the feasibility on the use of geopolymers in the design of new products with less CO2emissions and then the contribution to the sustainability in the construction sector.
Synthesis of Silver Nanoparticles with Potential Antifungical Activity for Bamboo Treatment
Authors: Pandoli Omar , Ventura Pereira-Meirelles Fatima , Monteiro Lobo Lobo Luz Eric , Assumpção Aline , dos Santos Martins Raquel , del Rosso Tommaso , Ghavami Khosrow
Published: October 2015

To increase the durability of bamboo it is important to find an easy method to fill the micro and meso structure of the biological matrix using a nanostructural material with an anti-fungical activity. A colloidal solution of silver nanoparticle (Ag-NPs) is a dispersion of metal nanoparticle in water with a diameter between 5-100 nm. Even if the biological mechanism is not completly understood yet, Ag-NPs show a satisfactory bactericidal and antifungical activity. We present a simple and rapid production of Ag-NPs made by a sol-gel synthesis in flow mode by means of microreactor tecnology through a chemical reduction of AgNO3 with NaBH4 in presence of two different organic ligands: sodium/potassium tartrate and trisodium citrate. The synthesis of Ag-NPs in continuous flow compared to the batch technique allowed to reduce the time of synthesis, facilitating the reproducibility of the process and consequently obtaining NPs with more uniform physical and chemical characteristics. The microorganisms of the genus Aspergillus were used for the microbiological tests. The effect of different Ag-NPs on microbial growth was observed daily. In particular, it was shown that the response of the fungus is inversely proportional to the size of the nanoparticles, cell growth is disrupt depending on the proportion between silver and organic ligand and microbialstatic effect, especially in relation to sporulation stage was also observed.
Carotid Artery Stent Continued Expansion Days after Deployment, without Post Stent Deployment Angioplasty
Authors: Qazi Umair , Obeid Tammam , Arhuidese Isibor , Malas Mahmoud
Published: October 2015

This is a carotid artery stent (CAS) case report, which avoids post-stent deployment angioplasty (Post-SDA), with duplex confirmed continued stent expansion at 1, 3 and 30-day post deployment. This report confirms that self-expanding nitinol stents in the carotid artery may not require Post-SDA. We believe CAS can be performed without Post-SDA, which helps reduce the occurrence of intraoperative hemodynamic depression.
Intramedullary thoracic spinal metastasis from small-cell lung cancer
Authors: Katsenos S. , Nikolopoulou M.
Published: October 2015

Intramedullary thoracic spinal metastasis from small-cell lung cancer. S. Katsenos, M. Nikolopoulou. Lung cancer with intramedullary spinal cord metastasis (ISCM) is a rare event exhibiting dismal prognosis. In the present paper, we describe a 74-year-old male who developed bilateral leg weakness with associated backache and non-productive cough. Chest imaging evaluation demonstrated pronounced bilateral mediastinal lymphadenopathy and a nodular opacity in the right lower lobe. The patient was diagnosed with small cell lung cancer through bronchoscopic procedures. Magnetic resonance imaging of the spinal cord with contrast-enhancement revealed an intramedullary lesion consistent with metastasis at the T5-T6 level. Despite chemotherapy and thoracic spine radiotherapy, he eventually succumbed to the disease 3 months after diagnosis. A brief overview of the current literature is also provided laying emphasis on the therapeutic strategies of this unusual extrathoracic metastatic disease.
Sildenafil improves clinical and functional status of an elderly postmenopausal female with ‘out of proportion’ PH associated with left heart disease
Authors: Correale Michele , Totaro Antonio , Ferraretti Armando , Di Biase Matteo , Brunetti Natale Daniele
Published: October 2015

We report a case of an elderly woman with heart failure with preserved ejection fraction and pulmonary hypertension (HFpEF-PH), refractory to conventional therapy for left heart failure and successfully treated by sildenafil.
The role of Dietitian in cardiac rehabilitation and secondary prevention
Authors: Agostini Susanna , Biffi Barbara , Brazzo Silvia , Da Vico Letizia , Masini Maria Luisa
Published: October 2015

Rehabilitation and secondary prevention programs are recognized as an essential part of the overall care of patients with cardiovascular disease. They consist of multidisciplinary strategies aiming at the reduction of modifiable risk factors for cardiovascular disease. There are some evidence of the efficacy of nutritional care in modifying eating habits and behavior in patients undergoing cardiac rehabilitation. In 2007, the Italian Association of Dietitians (ANDID) appointed a working group of dietitians, skilled in nutrition applied in cardiovascular disease, with the aim to make an overview of the available scientific literature and to develop a Professional Position Paper on the role of Dietitian in cardiac rehabilitation and secondary prevention. The first Position Paper, developed in 2008, covered the available evidence about the dietitian professional role and contribution in the management of the topic. The working group has recently updated the contents by introducing, in agreement with the work done by ANDID, the methodology of the Nutrition Care Process and Model (NCP), a systematic problem-solving method intended to stimulate critical thinking, decision-making and address issues related to food and nutritional assistance, in order to provide a safe, effective and high quality care.
Cardiologic evaluation of patients undergoing chemoterapy
Authors: Bordoni Barbara , Urbinati Stefano , Tosoni Alicia , Labanti Graziana , Brandes Alba
Published: October 2015

Life expectancy in patients affected by cancer has recently increased because of early diagnosis and actual therapies. In recent years, Oncology and Cardiology developed a tight relationship because of common risk factors (i.e. obesity, smoking, alcool intake, etc…), and for preventing the prothrombotic status due to cancer and the potential cardiotoxicity of chemotherapy. Cardiotoxicity incidence is reported from 1% up to 70% in retrospective analyses of drug protocols, mainly representing by left ventricular dysfunction (both reversible or irreversible), but also by arrhythmias, hypertension, atrioventricular block, coronary spasm, and arterial or venous thromboembolism. The early detection of the chemoterapy induced cardiotoxicity is now mandatory and can be obtained through a proper patients selection for different treatments and a strict monitoring during the follow-up period. The role of biomarkers of early cardiac damage, mainly, troponin I and brain natriuretic peptide-BNP, has been recently challenged, and algorithms are currently available. In the present paper, we propose how to perform a cardiological evaluation of patients undergoing chemoterapy tailored by the known adverse effects of the drugs.
Water pipe tobacco smoking: are the Bahraini smokers aware of its health effects?
Authors: Khalil Ebrahim , Ayyad Sajida Mansor , Al-Alawi Fatima S. Sharaf , Khalil Hasan A. Ali , Hassan Awadalla Muyassar Sabri , Asokan Govindaraj Vaithinathan
Published: October 2015

The tobacco epidemic kills half of its users annually and 600,000 deaths occur in people exposed to cigarette and water pipe tobacco (WT) smoking. A population-based cross sectional study was conducted to explore the knowledge and perceptions on health effects of WT smoking amongst Bahraini adults in the popular coffee shops of Bahrain and in women’s congregations. Randomly, 206 Bahraini adults of both genders were selected and distributed with a developed questionnaire to collect data; results were analyzed using SPSS (SPSS Inc., Chicago, IL, USA). Among the WT smokers, the highest proportion (45%) was observed between 21 and 30 age group and in the higher educational category. Majority smoked daily. The leading motives of WT smoking were meeting friends, passing of time and pleasure. Many smokers believed WT as less harmful than cigarettes, but affect the respiratory system, and causes: cancers, cardiovascular disease and pregnancy-related disorders. The knowledge scores were significantly higher in the younger age group, higher educational qualifications, and higher income. A considerable proportion of smokers perceived WT smoking as a sign of maturity, acceptable by the society. The perception scores were significantly higher in women and in the age group of >40. This study has revealed a lack of knowledge amongst the Bahraini adults who assume that health risks of WT are lower than cigarettes demanding further research to evaluate WT smoking risks, health effects, environmental effects of smoke, and regulatory services in Bahrain for a responsive approach to curb the WT tobacco epidemic.
Lyme carditis mimicking giant cell arteritis
Authors: Chauhan Krati
Published: October 2015

Presenting an interesting case of a patient who complained of myalgias, fatigue, headache, jaw claudication and scalp tenderness. Patient’s physical examination was unremarkable. Laboratory findings showed elevated erythrocyte sedimentation rate and C-reactive protein, bilateral temporal artery biopsy results were negative and first degree atrioventricular block was seen on electrocardiogram. Serology for Borrelia burgdorferi was positive; patient was diagnosed with Lyme carditis and treated with doxycycline. Lyme is a tick-borne, multi-system disease and occasionally its presentation may mimic giant cell arteritis. On follow-up there was complete resolution of symptoms and electrocardiogram findings.
The challenge of consciousness with special reference to the exclusive disjunction
Authors: Antonites Alex
Published: October 2015

The theory of evolution makes sense of the emergence of consciousness. Reduction is not wrong as such, but must not be totalised. The fact that we are star stuff does not preclude the novelty of consciousness. Materialism is naturalism, but naturalism need not be materialism. Neural pathways are relevant but are not the total picture. The central thesis is about David Chalmers’s philosophy being based on an exclusive disjunction. An inclusive disjunction is, when explained, more appropriate. Functionalism is appropriate. Thomas Nagel’s philosophy on first person ontology can still be maintained. Quantum and complexity theories’ hypothesis on consciousness is more compatible with freedom of decision than classical theories.
A Review of Melioidosis Cases in the Americas
Authors: Benoit Tina J. , Blaney David D. , Doker Thomas J. , Gee Jay E. , Elrod Mindy G. , Rolim Dionne B. , Inglis Timothy J. J. , Hoffmaster Alex R. , Bower William A. , Walke Henry T.
Published: October 2015

Melioidosis is a bacterial infection caused by Burkholderia pseudomallei, a gram-negative saprophytic bacillus. Cases occur sporadically in the Americas with an increasing number of cases observed among people with no travel history to endemic countries. To better understand the incidence of the disease in the Americas, we reviewed the literature, including unpublished cases reported to the Centers for Disease Control and Prevention. Of 120 identified human cases, occurring between 1947 and June 2015, 95 cases (79%) were likely acquired in the Americas; the mortality rate was 39%. Burkholderia pseudomallei appears to be widespread in South, Central, and North America.
The vibrating reed frequency meter: digital investigation of an early cochlear model
Authors: Bell Andrew , Wit Hero P.
Published: October 2015

The vibrating reed frequency meter, originally employed by Békésy and later by Wilson as a cochlear model, uses a set of tuned reeds to represent the cochlea’s graded bank of resonant elements and an elastic band threaded between them to provide nearest-neighbour coupling. Here the system, constructed of 21 reeds progressively tuned from 45 to 55 Hz, is simulated numerically as an elastically coupled bank of passive harmonic oscillators driven simultaneously by an external sinusoidal force. To uncover more detail, simulations were extended to 201 oscillators covering the range 1–2 kHz. Calculations mirror the results reported by Wilson and show expected characteristics such as traveling waves, phase plateaus, and a response with a broad peak at a forcing frequency just above the natural frequency. The system also displays additional fine-grain features that resemble those which have only recently been recognised in the cochlea. Thus, detailed analysis brings to light a secondary peak beyond the main peak, a set of closely spaced low-amplitude ripples, rapid rotation of phase as the driving frequency is swept, frequency plateaus, clustering, and waxing and waning of impulse responses. Further investigation shows that each reed’s vibrations are strongly localised, with small energy flow along the chain. The distinctive set of equally spaced ripples is an inherent feature which is found to be largely independent of boundary conditions. Although the vibrating reed model is functionally different to the standard transmission line, its cochlea-like properties make it an intriguing local oscillator model whose relevance to cochlear mechanics needs further investigation.
Signature of a tropical Pacific cyclone in the composition of the upper troposphere over Socorro, NM
Authors: Minschwaner K. , Manney G. L. , Petropavlovskikh I. , Torres L. A. , Lawrence Z. D. , Sutherland B. , Thompson A. M. , Johnson B. J. , Butterfield Z. , Dubey M. K. , Froidevaux L. , Lambert A. , Read W. G. , Schwartz M. J.
Published: October 2015

We present a case study based on balloon‐borne ozone measurements during the SouthEast American Consortium for Intensive Ozonesonde Network Study in August–September 2013. Data from Socorro, NM (34°N, 107°W) show a layer of anomalously low ozone in the upper troposphere (UT) during 8–14 August. Back trajectories, UT jet analyses, and data from the Microwave Limb Sounder (MLS) on the Aura satellite indicate that this feature originated from the marine boundary layer in the eastern/central tropical Pacific, where several disturbances and one hurricane (Henriette) formed within an active region of the Intertropical Convergence Zone in early August 2013. The hurricane and nearby convection pumped boundary layer air with low ozone (20–30 ppbv) into the UT. This outflow was advected to North America 3–5 days later by a strong subtropical jet, forming a tongue of low ozone observed in MLS fields and a corresponding layer of low ozone in Socorro vertical profiles.
Weakening of the weekend ozone effect over California's South Coast Air Basin
Authors: Baidar S. , Hardesty R. M. , Kim S.‐W. , Langford A. O. , Oetjen H. , Senff C. J. , Trainer M. , Volkamer R.
Published: October 2015

We have observed lower nitrogen dioxide (NO2) and ozone (O3) during a hot weekend (summer 2010) from aircraft over the entire South Coast Air Basin (SoCAB). Surface concentrations of NO2, O3, and temperature from 1996 to 2014 corroborate that this lower O3 on weekends is increasingly likely in recent years. While higher surface O3 on the weekends (weekend ozone effect, WO3E) remains widespread, the spatial extent and the trend in the probability of WO3E occurrences (PWO3E) have decreased significantly compared to a decade ago. This decrease is mostly the result of lower O3 on hot weekends in recent years. PWO3E is lowest in the eastern SoCAB. The major decrease happened during the 2008 economic recession, after which PWO3E has stabilized at a 15–25% lower level throughout most of the basin. Future NOx reductions are likely to be increasingly effective at reducing O3 pollution initially under hot conditions in the coming decade.
Monitoring and Control of Learning Own‐Race and Other‐Race Faces
Authors: Rhodes Matthew G. , Sitzman Danielle M. , Rowland Christopher A.
Published: October 2015

The own‐race bias refers to the finding that individuals are better able to recognize faces of the same race or ethnicity compared with faces of another race or ethnicity. The current study examined whether the own‐race bias was also evident in participants' predictions of memory performance and their self‐regulation of learning. In three experiments, participants studied own‐race and other‐race faces and predicted the likelihood of recognizing each face on a future test. Experiment 1 showed that participants provided similar predictions for own‐race and other‐race faces, despite superior recognition of own‐race faces. Experiments 2 and 3 permitted participants to control their study of faces and revealed better self‐regulation of learning for own‐race relative to other‐race faces. Collectively, these experiments suggest that the own‐race bias may partially reflect a metacognitive deficiency, as participants are less able to effectively self‐regulate learning for other‐race faces. The implications of these findings are discussed. Copyright © 2013 John Wiley & Sons, Ltd.
New Malacovia
Authors: Bronner Pascal
Published: October 2015

In his 2009 award‐winning design thesis project for the Bartlett School of Architecture (UCL), Pascal Bronner evokes the imaginary land of New Malacovia. Using an existing text as a catalyst, and graphite as the sole medium, Bronner transforms the inventions and urban ideas of an original fictionalised city afresh into a speculative environmental programme: a potato‐fuelled miniature city is laid out on foundations of bottle corks.
A World Below
Authors: Kulper Perry
Published: October 2015

The shift from hand drawing to the digital has often centred on the subject of media. Here, however, Perry Kulper discusses how leaving behind conventional graphic formats, such as those of the plan, section and elevation, opens up the possibilities of fusing visualisation and thinking. Kulper is fluid in his uses of techniques and design methods, tailoring them to explore a fit between what is being worked on, when it is being worked on and how it is being worked on ‐ in the quest for a ‘relational synthesis’.
Programmable Biopolymers for Advancing Biomedical Applications of Fluorescent Nanodiamonds
Authors: Wu Yuzhou , Ermakova Anna , Liu Weina , Pramanik Goutam , Vu Tran Minh , Kurz Andrea , McGuinness Liam , Naydenov Boris , Hafner Susanne , Reuter Rolf , Wrachtrup Joerg , Isoya Junichi , Förtsch Christina , Barth Holger , Simmet Thomas , Jelezko Fedor , Weil Tanja
Published: October 2015

A versatile biopolymer platform for advancing nanodiamonds (NDs) as unique magnetooptic materials for biomedical applications is presented here. Precision biopolymer coatings are designed by chemical reprogramming the functionalities of serum albumin via a straightforward synthesis protocol. Such biopolymers offer high biocompatibility and precise modification with various functional entities due to the large number of available reactive amino acid residues. Premodification of these biopolymers provides a convenient approach to customized surface functionalization of NDs. As an example, the anticancer drug doxorubicin (DOX) is conjugated to the biopolymer with high reproducibility and full characterization. The biopolymer‐coated NDs reveal excellent colloidal stabilities in all physiological media tested, even after loading with high numbers of hydrophobic DOX. The intracellular distribution of NDs and DOX is analyzed in living cells by recording the fluorescence spectra in different cellular compartments, which proves efficient intracellular release of DOX from the carrier. Studies in vitro as well as in a chick tumor xenograft model reveal efficient antitumor effects. The facile and versatile biopolymer coating strategy reported herein will greatly accelerate the availability of customized NDs with reliable and reproducible features to exploit their great potential in single molecular bioimaging, in vivo biosensing, and high resolution quantum optics.
Approaching the Theoretical Capacity of Li3VO4 via Electrochemical Reconstruction
Authors: Ni Shibing , Zhang Jicheng , Ma Jianjun , Yang Xuelin , Zhang Lulu , Li Xiaoming , Zeng Haibo
Published: October 2015

Li3VO4 is a potential anode for Li‐ion batteries owing to its safe discharge plateau and high capacity, but the reported reversible capacity is still far from its theoretical value (592 mAh g−1). Here, for the first time, a Li3VO4 anode is reported with reversible capacity approaching the theoretical value. Li3VO4 aggregates hybridized with carbon (Li3VO4/C) are first fabricated, and then dramatically transform into well dispersed Li3VO4 nanocrystals (NCs) anchoring on carbon nanoflakes (NFs) by electrochemical reconstruction. In the Li3VO4/C NC‐on‐NF structures, the small‐sized Li3VO4 NCs, the flexible carbon NFs, and the good dispersity provide high Li‐ion storage, electronic conductivity and stability, respectively. Resultingly, outstanding electrochemical performance of the Li3VO4/C is achieved with discharge and charge capacities of 542 and 541 mAh g−1 after 300 cycles at a specific current of 150 mA g−1. After 1000 cycles at a specific current of 2000 mA g−1, the discharge and charge capacities are maintained at 422 and 421 mAh g−1. When matching with a 4 V cathode, the specific energy density of the Li3VO4/C is 4.2 times of Li4Ti5O12 and 1.2 times of graphite, and the volumetric energy density is 3.2 times of Li4Ti5O12 and 1.4 times of graphite.
Leaching‐Free Supported Gold Nanoparticles Catalyzing Cycloisomerizations under Microflow Conditions
Authors: Schröder Felix , Erdmann Nico , Noël Timothy , Luque Rafael , Van der Eycken Erik V.
Published: October 2015

A continuous‐flow protocol for the gold‐catalyzed cycloisomerization of sterically hindered Ugi‐adducts to spiroindolines in a packed‐bed reactor is presented. Spiroindolines with various substitution patterns are formed in good yields and with good selectivity. A detailed characterization of the catalyst deactivation process was conducted, whereas no metal leaching from the catalyst was detected.

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Synthesis of the Stable Ordered Conjugated Polymer Poly(dibromodiacetylene) from an Explosive Monomer
Authors: Jin Hongjian , Young Christopher N. , Halada Gary P. , Phillips Brian L. , Goroff Nancy S.
Published: October 2015

Dibromobutadiyne is an extremely unstable compound that explodes at room temperature, even under inert atmosphere. This instability has limited the studies of dibromobutadiyne almost entirely to spectroscopic characterization. Here we report an approach to control the reactivity of dibromobutadiyne, via topochemical reaction in cocrystals, leading to the ordered polymer poly(dibromodiacetylene), PBDA. At low temperatures (−15 to −18 °C), dibromobutadiyne can form cocrystals with oxalamide host molecules containing either pyridyl or nitrile side groups, in which halogen bonds align the dibromobutadiyne monomers for topochemical polymerization. The cocrystals with the bis(nitrile) oxalamide host undergo complete ordered polymerization to PBDA, demonstrated by solid‐state MAS‐NMR, Raman, and optical absorption spectroscopy. Once formed, the polymer can be separated from the host; unlike the monomer, PBDA is stable at room temperature.
Ceria–Zirconia Particles Wrapped in a 2D Carbon Envelope: Improved Low‐Temperature Oxygen Transfer and Oxidation Activity
Authors: Aneggi Eleonora , Rico‐Perez Veronica , de Leitenburg Carla , Maschio Stefano , Soler Lluís , Llorca Jordi , Trovarelli Alessandro
Published: October 2015

Engineering the interface between different components of heterogeneous catalysts at nanometer level can radically alter their performances. This is particularly true for ceria‐based catalysts where the interactions are critical for obtaining materials with enhanced properties. Here we show that mechanical contact achieved by high‐energy milling of CeO2–ZrO2 powders and carbon soot results in the formation of a core of oxide particles wrapped in a thin carbon envelope. This 2D nanoscale carbon arrangement greatly increases the number and quality of contact points between the oxide and carbon. Consequently, the temperatures of activation and transfer of the oxygen in ceria are shifted to exceptionally low temperatures and the soot combustion rate is boosted. The study confirms the importance of the redox behavior of ceria‐zirconia particles in the mechanism of soot oxidation and shows that the organization of contact points at the nanoscale can significantly modify the reactivity resulting in unexpected properties and functionalities.
High‐Resolution Crystal Structure of a Silver(I)–RNA Hybrid Duplex Containing Watson–Crick‐like CSilver(I)C Metallo‐Base Pairs
Authors: Kondo Jiro , Tada Yoshinari , Dairaku Takenori , Saneyoshi Hisao , Okamoto Itaru , Tanaka Yoshiyuki , Ono Akira
Published: October 2015

Metallo‐base pairs have been extensively studied for applications in nucleic acid‐based nanodevices and genetic code expansion. Metallo‐base pairs composed of natural nucleobases are attractive because nanodevices containing natural metallo‐base pairs can be easily prepared from commercially available sources. Previously, we have reported a crystal structure of a DNA duplex containing THgIIT base pairs. Herein, we have determined a high‐resolution crystal structure of the second natural metallo‐base pair between pyrimidine bases CAgIC formed in an RNA duplex. One AgI occupies the center between two cytosines and forms a CAgIC base pair through N3AgIN3 linear coordination. The CAgIC base pair formation does not disturb the standard A‐form conformation of RNA. Since the CAgIC base pair is structurally similar to the canonical Watson–Crick base pairs, it can be a useful building block for structure‐based design and fabrication of nucleic acid‐based nanodevices.
Renewable Feedstocks: The Problem of Catalyst Deactivation and its Mitigation
Authors: Lange Jean‐Paul
Published: October 2015

Much research has been carried out in the last decade to convert bio‐based feedstock into fuels and chemicals. Most of the research focuses on developing active and selective catalysts, with much less attention devoted to their long‐term stability. This Review considers the main challenges in long‐term catalyst stability, discusses some fundamentals, and presents options for their mitigation. Three main challenges are discussed: catalyst fouling, catalyst poisoning, and catalyst destruction. Fouling is generally related to the deposition of insoluble components present in the feed or formed by degradation of the feed or intermediates. Poisoning is related to the deposition of electropositive contaminants (e.g. alkali and alkaline earth metals) on acid sites or of electronegative contaminants (e.g. N and S) at hydrogenation sites. Catalyst destruction results from the thermodynamic instability of most oxidic supports, solid acids/bases, and hydrogenation functions under hydrothermal conditions.
An Interview with Laurie MacKinnon, PhD, 2012 ANZJFT Special Award Recipient and A Personal Tribute by Kerrie James
Authors: Beauchamp Julie
Published: October 2015

In this interview with Laurie MacKinnon, MSW, PhD, the 2012 ANZJFT recipient of the Special Award for Distinguished Contributions to Family Therapy, Julie Beauchamp discusses with Laurie her perspective on family therapy in Australia, the significance of feminism and family of origin work for family therapy, her writing and memorable experiences, collaboration with Kerrie James and her integration of a trauma perspective into couple and family therapy.
Effect of the maleation of lignosulfonate on the mechanical and thermal properties of lignosulfonate/poly(ε‐caprolactone) blends
Authors: Wang Fei , Yang Xuping , Zou Yangxue
Published: October 2015

Maleated lignosulfonate (MLS) produced by esterification with maleic anhydride and unmodified lignosulfonate [in the form of lignosulfonic acid (LS)] were incorporated into poly(ε‐caprolactone) (PCL) via melt‐blending. The obtained MLS/PCL composites and LS/PCL composites were characterized by Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric (TG) analysis, and electronic universal testing. The FTIR and DSC results show that the interactions between MLS and PCL were stronger than those between LS and PCL, whereas the TG analysis indicated that the LS/PCL composite was more thermally stable than the MLS/PCL composite. The tensile strength of the MLS/PCL blends remained at about 18 MPa when the MLS content reached 50 wt %; this was about 1.7 times larger than that of the LS/PCL blend. The Young's modulus was also enhanced; this indicated an improvement in the mechanical properties. The results show that the maleation of lignosulfonate was beneficial for enhancing the mechanical properties of these blends. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42925.
Effect of pigmentation on polyurethane/polysiloxane hybrid coatings
Authors: Gao Tongzhai , Maya‐Visuet Enrique , He Zhouying , Castaneda‐Lopez Homero , Zvonkina Irina J. , Soucek Mark D.
Published: October 2015

Rutile TiO2 was formulated into polyurethane/polysiloxane hybrid coatings in order to investigate the influence of pigmentation on the inorganic phase of the hybrid coatings. Two urethanes were prepared from the isocyanurate of hexane diisocyanate (HDI), alkoxysilane modified HDI, and tetraethyl orthosilicate (TEOS) oligomers, with oligoesters derived from either cyclohexane diacids (CHDA) and 2‐butyl‐2‐ethyl‐1,3‐propanediol (BEPD) or adipic acid (AA), isophthalic acid (IPA), 1,6‐hexanediol (HD), and trimethylol propane (TMP). The oligoesters were spectroscopically characterized using GPC, FT‐IR, and NMR. Chemical interaction between the TiO2 and the sol–gel precursor was investigated using solid‐state 29Si NMR and XPS. The morphology, mechanical, viscoelastic, thermal properties of the pigmented coatings are evaluated as a function of pigmentation volume concentration (PVC). Using AFM and SEM, the pigment was observed to be well dispersed in the polymer binder. The thermal stability, the tensile modulus, and strength of the coatings were enhanced with increasing PVC, whereas the pull‐off adhesion and flexibility (elongation‐at‐break) were reduced with increasing PVC. Finally, the pigmented coatings were evaluated by electrochemical impedance spectroscopy (EIS) and the results showed that 10 wt % of the pigment improved the corrosion resistance of the entire coating system. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42947.
Novel dynamic model for aerated shaking bioreactors
Authors: Tabrizi Hamed Osouli , Amoabediny Ghassem , Moshiri Behzad , Haji Abbas Mahdi Pesaran , Pouran Behdad , Imenipour Emad , Rashedi Hamid , Büchs Jochen
Published: October 2015

A novel mathematical model of aerated shaking bioreactors is developed and its accuracy is evaluated with experimental data. Corynebacterium glutamicum (DM 1730) and Arxula adeninivorans (WT LS3) are used as model microorganisms. In order to get the experimental data, shake flasks of 250 mL and filling volume of 15 mL, together with online measurement tools for measuring oxygen transfer rate and tools for measuring dry biomass concentration, are used. This mathematical model may be regarded as a key tool for computational simulations or developing model‐based control approaches for necessary automation and optimization purposes. Moreover, the error evaluation presented in this paper should be taken into account when using the model. The squared Pearson product‐moment correlation coefficient (r2) and average deviation of error are used as two statistical criteria to quantify the accuracy and consistency of the model. The r2 for biomass concentration equals 0.95 for C. glutamicum (DM 1730) and 0.93 for A. adeninivorans (WT LS3). The reported average deviation of error of biomass concentration approaches 17.4% for C. glutamicum (DM 1730) and 26.7% for A. adeninivorans (WT LS3).
Toward regeneration of articular cartilage
Authors: Iwamoto Masahiro , Ohta Yoichi , Larmour Colleen , Enomoto‐Iwamoto Motomi
Published: October 2015

Articular cartilage is classified as permanent hyaline cartilage and has significant differences in structure, extracelluar matrix components, gene expression profile, and mechanical property from transient hyaline cartilage found in the epiphyseal growth plate. In the process of synovial joint development, articular cartilage originates from the interzone, developing at the edge of the cartilaginous anlagen, and establishes zonal structure over time and supports smooth movement of the synovial joint through life. The cascade actions of key regulators, such as Wnts, GDF5, Erg, and PTHLH, coordinate sequential steps of articular cartilage formation. Articular chondrocytes are restrictedly controlled not to differentiate into a hypertrophic stage by autocrine and paracrine factors and extracellular matrix microenvironment, but retain potential to undergo hypertrophy. The basal calcified zone of articular cartilage is connected with subchondral bone, but not invaded by blood vessels nor replaced by bone, which is highly contrasted with the growth plate. Articular cartilage has limited regenerative capacity, but likely possesses and potentially uses intrinsic stem cell source in the superficial layer, Ranvier's groove, the intra‐articular tissues such as synovium and fat pad, and marrow below the subchondral bone. Considering the biological views on articular cartilage, several important points are raised for regeneration of articular cartilage. We should evaluate the nature of regenerated cartilage as permanent hyaline cartilage and not just hyaline cartilage. We should study how a hypertrophic phenotype of transplanted cells can be lastingly suppressed in regenerating tissue. Furthermore, we should develop the methods and reagents to activate recruitment of intrinsic stem/progenitor cells into the damaged site. Birth Defects Research (Part C) 99:192–202, 2013. © 2013 Wiley Periodicals, Inc.
Quantifizierung von DNA durch Absorptionsmessung
Authors: Hauk Andrea
Published: October 2015

Die Konzentration von Nukleinsäuren in Lösung lässt sich durch die Messung der UV‐Absorption bei 260nm im Photometer bestimmen. Hierzu füllt man die zu messende Probe in eine Küvette und setzt diese in den Strahlengang des Photometers ein. Dort wird gemessen, wieviel Licht der Wellenlänge 260nm von den Nukleinsäuren in der Probe absorbiert und wieviel durchgelassen wird. Das Ergebnis wird als “Extinktion” angezeigt. Doch wie errechnet sich aus diesem Wert die Konzentration der DNA in der Probe? Und worauf sollte man bei der Messung achten, um ein genaues Ergebnis zu erhalten?
Kinetic Study on Reactions of O‐Y‐substituted Phenyl Thionobenzoates with Quinuclidine: Factors Governing Reactivity and Reaction Mechanism
Authors: Yang Eun‐Ji , Kim Min‐Young , Um Ik‐Hwan
Published: October 2015

Second‐order rate constants (k
quin) for the reactions of O‐Y‐substituted phenyl thionobenzoates (3a–3i) with quinuclidine have been measured spectrophotometrically. Comparison of k
quin with the rate constants reported previously for the corresponding reactions with benzylamine (k
BzNH2) has revealed that quinuclidine is less reactive than benzylamine toward 3a–3i although the former is 2.1 pK
a units more basic than the latter. Steric hindrance exerted by quinuclidine has been suggested to be responsible for the decreased reactivity of the tertiary amine. The Brønsted‐type plot for the reactions of 3a–3i with quinuclidine is linear with βlg = −0.37. The Hammett plot correlated with constants exhibits many scattered points (
R
2
 = 0.982). In contrast, the Yukawa‐Tsuno plot results in an excellent linear correlation (
R
2
 = 0.9992) with ρ
Y
 = 0.96 and r = 0.51, indicating that a negative charge develops partially on the O atom of the leaving group. Thus, the reactions of 3a–3i with quinuclidine have been concluded to proceed through a concerted mechanism in which expulsion of the leaving group is advanced only a little in the rate‐determining transition state.
Molecular Dynamics Simulation Studies of Mid‐Size Liquid n‐Alkanes, C12–C160
Authors: Kwon Tae Woo , Lee Song Hi
Published: October 2015

In this study, we report the results of molecular dynamics simulations (MD) for model systems of mid‐size liquid n‐alkanes (C12–C160
) at several temperatures (~2700 K) in canonical ensembles to calculate structural and dynamic properties (viscosity η, self‐diffusion constant D, and monomeric friction constant ζ). For the small n‐alkanes for n ≤ 80, the chains are clearly , which leads to the conclusion that the liquid n‐alkanes are far away from the Rouse regime, but for the n‐alkanes for n ≥ 120, the chains are and they are Gaussian. It is found that the long chains of these n‐alkanes at high temperatures show abnormalities in density, viscosity, and monomeric friction constant. The mass and temperature dependences of structural and dynamic properties (η, D, and ζ) are discussed.
Differentiating Chamaecyparis obtusa and Chamaecyparis pisifera Leaves Using 1H Nuclear Magnetic Resonance Spectroscopy
Authors: Oh Il‐Hwan , Cho In Hee , Kim So‐Hyun , Oh Taek‐Joo , Lee Hong Jin , Kim Young‐Suk , Choi Hyung‐Kyoon
Published: October 2015

Chamaecyparis obtusa and Chamaecyparis pisifera are cypress species native to and widely distributed in Japan and South Korea that belong to the Cupressaceae family. Various pharmacological properties that have been identified in these species could be useful in the development of medicinal products, and the ability to differentiate these two species has become essential due to their different specific pharmacological properties. Metabolic analysis using
1H nuclear magnetic resonance spectroscopy coupled with multivariate statistical techniques was performed to elucidate the differences between C. obtusa and C. pisifera leaves. An optimized partial least‐squares discriminant analysis (PLS‐DA) model for their discrimination was obtained by selecting variables based on a cutoff for their importance in the projection value of 1.1. The following 24 compounds were profiled and compared between C. obtusa and C. pisifera leaves: 2‐hydroxyisobutyrate, acetate, catechin, choline, glucose, betaine, malonate, 4‐hydroxyphenylacetate, homovanillate, fructose, 5‐hydroxyindoleacetate, glycine, sucrose, glycolate, tartrate, 3,4‐dihydroxymandelate, uracil, myricetin, fumarate, 4‐hydroxybenzoate, protocatechuate, cinnamate, hypoxanthine, and formate. The key compounds contributing to the discrimination of the two leaf types were found to be acetate, homovanillate, protocatechuate, sucrose, catechin, formate, 2‐hydroxyisobutyrate, and hypoxanthine.
Synthesis of Novel Ligustrazine Derivatives as Na+/H+ Exchange Inhibitors
Authors: Ren Mei , Dong Jin , Xu Yungen , Wen Nan , Gong Guoqing
Published: October 2015

A novel series of 3,5,6‐trimethylpyrazine‐2‐methoxy (or methylamino) substituted benzoyl‐guanidine derivatives were designed and synthesized as Na+/H+ exchange (NHE) inhibitors. In this study, compounds with electron‐withdrawing substituents on the benzene ring seemed to improve NHE‐1 inhibitory activities. Compounds 6d, 6k, and 6l were found to be potent inhibitors of NHE‐1 (IC50=3.0±1.6, 3.0±1.4, and 1.6±0.4 nmol/l, resp.). Furthermore, they showed a remarkable reduction of infarct size in the rat myocardial infarction model in vivo.