bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular Rotors in Porous Organic Frameworks
Authors: Comotti Angiolina , Bracco Silvia , Ben Teng , Qiu Shilun , Sozzani Piero
Published: January 2014

Porous organic frameworks perform a variety of functions, owing to their extremely large surface areas, but the dynamics of the structural elements have never been explored. Our discovery of ultra‐fast molecular rotors (106 Hz at 225 K) in their architectures allows us to look at them from a new perspective. The constructive elements are robust struts and rapid rotors, resulting in a dynamic material whose motion can be frozen or released at will. The rotational motion can be actively regulated in response to guests. As the temperature is increased, the rotors spin ever faster, approaching free‐rotational diffusion at 550 K. The unusual combination of remarkable nanoporosity with fast dynamics is intriguing for engineering oscillating dipoles and producing responsive materials with switchable ferroelectricity, and for applications spanning from sensors to actuators, which capture and release chemicals on command.
Asymmetric NH Insertion of Secondary and Primary Anilines under the Catalysis of Palladium and Chiral Guanidine Derivatives
Authors: Zhu Yin , Liu Xiaohua , Dong Shunxi , Zhou Yuhang , Li Wei , Lin Lili , Feng Xiaoming
Published: January 2014

Efficient enantioselective NH insertion reactions of secondary and primary anilines were catalyzed by palladium(0) in combination with chiral guanidine derivatives. A broad range of substituted anilines were tolerated, and the corresponding products were obtained in high yield (up to 99 %) with good enantioselectivity (up to 94 % ee) under mild reaction conditions. The NH insertion mechanism was examined by the study of kinetic isotope effects, control experiments, HRMS, and spectroscopic analysis.
Crystallization behavior of spray‐dried and freeze‐dried graphene oxide/poly(trimethylene terephthalate) composites
Authors: Guo Chengxin , Ji Liangliang , Li Yaowen , Yang Xiaoming , Tu Yingfeng
Published: January 2014

Two types of graphene oxide (GO) powders were prepared by freeze‐drying or spray‐drying method, and their composites with poly(trimethylene terephthalate) (PTT) were prepared by melt blending. The influence of GO powders' type and content on crystallization behavior of PTT was investigated by differential scanning calorimeter (DSC) and polarized optical microscopy (POM). DSC results indicated that the overall crystallization rate of PTT was accelerated by well‐dispersed GO material which acts as a heterogeneous nucleation agent, since the Avrami parameter obtained is near 3. On the contrary, large GO aggregates which is in the minority will hinder the nucleation. Interestingly, large and well‐defined PTT spherulites instead of tremendous stunted spherulites were observed from POM, which means only a small portion of GO powders was acted as nucleation agent. Meanwhile, GO powders had no effect on PTT spherulites growth rate. In addition, the band spacing of PTT spherulites became weaker and wider with increasing GO content. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40332.
Scuba diving with the grey nurse shark (Carcharias taurus): an application of the theory of planned behaviour to identify divers beliefs
Authors: Apps Kirin , Lloyd David , Dimmock Kay
Published: January 2014

Scuba diving with the critically endangered grey nurse shark (Carcharias taurus) is a popular attraction for divers on the east coast of Australia. As the popularity of shark diving develops globally, research is required to evaluate how diving with sharks affects the behaviour and ecology of the species. Understanding participant's behaviour when diving with C. taurus can provide valuable information for researchers and policy makers trying to conserve this species.

An elicitation procedure based on the theory of planned behaviour was applied to determine divers’ beliefs pertinent to approaching C. taurus when scuba diving at two sites on Australia's east coast. A content analysis of responses revealed preliminary insights into the salient beliefs of divers. This initial step is an essential foundation for subsequent phases of research and communication aimed at improving shark and diver interactions and experiences.

Copyright © 2014 John Wiley & Sons, Ltd.
The benefits of fringing mangrove systems to Mumbai
Authors: Everard Mark , Jha Rohit RS , Russell Shaun
Published: January 2014

Mumbai's mangroves have been significantly depleted through historical city development and continuing encroachment. These mangroves are important for production of a range of ecosystem services.

Recent conservation‐oriented orders in India's courts of justice recognize some of the values associated with mangroves, though wider benefits flow to diverse stakeholders through many additional ecosystem services provided by Mumbai's remaining fringe of mangrove systems.

Valuation of ecosystem services on a semi‐quantitative basis and, where possible, using value‐transfer techniques from other relevant studies, demonstrates in indicative terms the magnitude of the benefits provided to Mumbai by its mangrove systems and connected habitats. Values could only be deduced approximately as most services lie outside the current market.

Conservative valuation and assumptions about cumulative, non‐quantified value emphasize the importance of mangroves to the built environment, people, and future security of Mumbai. This reinforces the need for conservation and restoration of the mangrove resource, particularly as a matter of ‘natural insurance’ in the light of a changing climate, sea‐level rise and other emerging sustainability challenges.

Current mangrove extent is at its most sparse on the seaward border of the city, arguably where greatest protection is required from storms, tsunamis, and other threats.

Investment in mangrove restoration would add significant value to the city region. Novel economic tools such as ‘payments for ecosystem services’ (PES) may be used to protect or enhance the mangrove stands of Mumbai.

Copyright © 2014 John Wiley & Sons, Ltd.
Primary Angiitis of the Central Nervous System: Description of the First Fifty‐Two Adults Enrolled in the French Cohort of Patients With Primary Vasculitis of the Central Nervous System
Authors: de Boysson Hubert , Zuber Mathieu , Naggara Olivier , Neau Jean‐Philippe , Gray Françoise , Bousser Marie‐Germaine , Crassard Isabelle , Touzé Emmanuel , Couraud Pierre‐Olivier , Kerschen Philippe , Oppenheim Catherine , Detante Olivier , Faivre Anthony , Gaillard Nicolas , Arquizan Caroline , Bienvenu Boris , Néel Antoine , Guillevin Loïc , Pagnoux Christian ,   for the French Vasculitis Study Group and the French NeuroVascular Society
Published: January 2014

Objective

To describe characteristics and outcomes of a multicenter cohort of patients diagnosed as having primary angiitis of the central nervous system (PACNS).

Methods

In 2010, we initiated a cohort study of adults diagnosed as having PACNS ≤15 years ago and with followup of >6 months (unless they died earlier of biopsy‐proven PACNS). Its first analysis was planned at 2 years. Multidisciplinary investigators verified that appropriate investigations were done and excluded patients with possible alternative diagnoses. We analyzed patient demographics and symptoms, laboratory, radiographic, and histologic findings, and treatments. Studied outcomes included treatment response(s), relapse, death, and disability.

Results

We included 52 patients (30 males; median age at diagnosis 43.5 years [range 18–79 years]) in whom PACNS was diagnosed between 1996 and 2012. Nineteen (61%) of 31 patients who had undergone brain biopsy had histologic vasculitis (biopsy‐proven PACNS), while the other 12 patients had normal or noncontributive biopsy samples. An additional 21 patients had signs suggestive of PACNS on conventional cerebral angiography. All but 1 patient received corticosteroids, and 44 patients received cyclophosphamide (CYC). After a median followup of 35 months (range 2–148 months) postdiagnosis (1 patient with biopsy‐proven PACNS died 2 months after diagnosis), 32 patients responded to treatment with improved modified Rankin scale scores, 4 patients (8%) did not respond, 14 patients (27%) had relapse of their disease at least once, and 3 patients (6%) died (1 patient after a relapse). Relapse was more common in patients with than in those without meningeal gadolinium enhancements on magnetic resonance imaging (MRI) (8 of 10 [80%] versus 6 of 32 [19%]; P = 0.001) and more common in patients with than in those without seizures at diagnosis (8 of 17 [47%] versus 6 of 35 [17%]; P = 0.04).

Conclusion

In this cohort of patients with PACNS, most patients received corticosteroids and CYC, and mortality was low. Patients with seizures at diagnosis or meningeal enhancements on MRI may be prone to relapse and require a different treatment strategy.
Periodontitis and Porphyromonas gingivalis in Patients With Rheumatoid Arthritis
Authors: Mikuls Ted R. , Payne Jeffrey B. , Yu Fang , Thiele Geoffrey M. , Reynolds Richard J. , Cannon Grant W. , Markt Jeffrey , McGowan David , Kerr Gail S. , Redman Robert S. , Reimold Andreas , Griffiths Garth , Beatty Mark , Gonzalez Shawneen M. , Bergman Debra A. , Hamilton Bartlett C. , Erickson Alan R. , Sokolove Jeremy , Robinson William H. , Walker Clay , Chandad Fatiha , O'Dell James R.
Published: January 2014

Objective

To examine the degree to which shared risk factors explain the relationship of periodontitis (PD) to rheumatoid arthritis (RA) and to determine the associations of PD and Porphyromonas gingivalis with pathologic and clinical features of RA.

Methods

Patients with RA (n = 287) and patients with osteoarthritis as disease controls (n = 330) underwent a standardized periodontal examination. The HLA–DRB1 status of all participants was imputed using single‐nucleotide polymorphisms from the extended major histocompatibility complex. Circulating anti–P gingivalis antibodies were measured using an enzyme‐linked immunosorbent assay, and subgingival plaque was assessed for the presence of P gingivalis using polymerase chain reaction (PCR). Associations of PD with RA were examined using multivariable regression.

Results

Presence of PD was more common in patients with RA and patients with anti–citrullinated protein antibody (ACPA)–positive RA (n = 240; determined using the anti–cyclic citrullinated peptide 2 [anti–CCP‐2] test) than in controls (35% and 37%, respectively, versus 26%; P = 0.022 and P = 0.006, respectively). There were no differences between RA patients and controls in the levels of anti–P gingivalis or the frequency of P gingivalis positivity by PCR. The anti–P gingivalis findings showed a weak, but statistically significant, association with the findings for both anti–CCP‐2 (r = 0.14, P = 0.022) and rheumatoid factor (RF) (r = 0.19, P = 0.001). Presence of PD was associated with increased swollen joint counts (P = 0.004), greater disease activity according to the 28‐joint Disease Activity Score using C‐reactive protein level (P = 0.045), and higher total Sharp scores of radiographic damage (P = 0.015), as well as with the presence and levels of anti–CCP‐2 (P = 0.011) and RF (P < 0.001). The expression levels of select ACPAs (including antibodies to citrullinated filaggrin) were higher in patients with subgingival P gingivalis and in those with higher levels of anti–P gingivalis antibodies, irrespective of smoking status. Associations of PD with established seropositive RA were independent of all covariates examined, including evidence of P gingivalis infection.

Conclusion

Both PD and P gingivalis appear to shape the autoreactivity of RA. In addition, these results demonstrate an independent relationship between PD and established seropositive RA.
A Stable Porous Anionic Metal–Organic Framework for Luminescence Sensing of Ln3+ Ions and Detection of Nitrobenzene
Authors: Qin Jun‐Sheng , Bao Shao‐Juan , Li Peng , Xie Wei , Du Dong‐Ying , Zhao Liang , Lan Ya‐Qian , Su Zhong‐Min
Published: January 2014

A hexagonal channel‐based porous anionic metal–organic framework was successfully constructed. IFMC‐3 is stable in air and acidic/basic aqueous solutions at room temperature, and constitutes a selective luminescent sensing material for Ln3+ ions and a recyclable probe for the sensitive detection of nitrobenzene.
Role of anatomical right hepatic trisectionectomy for perihilar cholangiocarcinoma
Authors: Matsumoto N , Ebata T , Yokoyama Y , Igami T , Sugawara G , Shimoyama Y , Nagino M
Published: January 2014

Background

Right-sided hepatectomy is often selected for perihilar cholangiocarcinoma because the extrahepatic portion of the left hepatic duct is longer than that of the right hepatic duct. However, the length of resected left hepatic duct in right-sided hepatectomy has not been reported.

Methods

Patients who underwent right-sided hepatectomy for perihilar cholangiocarcinoma were reviewed retrospectively. Trisectionectomies were performed according to a previously reported technique of anatomical right hepatic trisectionectomy. Right hepatectomy was performed according to standard operative procedures. The length of resected left hepatic duct was measured.

Results

Thirty-three patients underwent right trisectionectomy and 141 had a right hemihepatectomy. Patients having a trisectionectomy had more advanced tumours and so required combined portal vein resection more frequently. Duration of surgery and blood loss were similar in the two groups. Morbidity and mortality rates tended to be higher following hemihepatectomy than after trisectionectomy. The mean(s.d.) length of resected left hepatic duct was significantly greater in trisectionectomy than in hemihepatectomy (25·0(6·9) versus 14·8(5·3) mm; P < 0·001). In patients with Bismuth type IV tumours, the percentage of negative left hepatic duct margins was significantly higher for trisectionectomy than for hemihepatectomy (89 versus 57 per cent; P = 0·021). Achievement of R0 resection was similar and survival did not differ between the two groups, despite different tumour load.

Conclusion

Compared with right hemihepatectomy, anatomical right hepatic trisectionectomy provides a greater length of resected hepatic duct, leading to a high proportion of negative proximal ductal margins even in patients with Bismuth type IV tumours.
Identification of astilbin metabolites produced by human intestinal bacteria using UPLC‐Q‐TOF/MS
Authors: Zhao Min , Xu Jun , Qian Dawei , Guo Jianming , Jiang Shu , Shang Er‐xin , Duan Jin‐ao
Published: January 2014

Astilbin, mainly isolated from a commonly used herbal medicine, Smilax glabra Roxb (SGR), exhibits a variety of pharmacological activities and biological effects. It is metabolized by intestinal bacteria after oral administration which leads to the variation of ethnopharmacological profile of this traditional medicine. However, little is known on the interactions of this active compound with intestinal bacteria, which would be very helpful in unravelling how SGR works. In this study, different pure bacteria from human feces were isolated and were used to investigate their conversion capability of astilbin. Ultra‐performance liquid chromatography/quadrupole‐time‐of‐flight mass spectrometry (UPLC‐Q‐TOF/MS) technique combined with MetabolynxTM software was used to analyze astilbin and its metabolites. The parent compound and two metabolites (quercetin and eriodictyol) were detected in the isolated bacterial samples compared with blank samples. Quercetin was present in Enterococcus sp. 8B, 8–2 and 9–2 samples. Eriodictyol was only identified in Enterococcus sp. 8B sample. The metabolic routes and metabolites of astilbin produced by the different intestinal bacteria are reported for the first time. This will be useful for the investigation of the pharmacokinetic study of astilbin in vivo and the role of different intestinal bacteria in the metabolism of natural compounds. Copyright © 2014 John Wiley & Sons, Ltd.
Isolation and characterization of lung resident mesenchymal stem cells capable of differentiating into alveolar epithelial type II cells
Authors: Gong Xuemin , Sun Zhaorui , Cui Di , Xu Xiaomeng , Zhu Huiming , Wang Lihui , Qian Weiping , Han Xiaodong
Published: January 2014

Controversies and risks continue to be reported about exogenous mesenchymal stem cell‐based therapies. In contrast with employing exogenous stem cells, making use of lung resident mesenchymal stem cells (LR‐MSCs) could be advantageous. Our study sought to isolate the LR‐MSCs and explore their potential to differentiate into alveolar epithelial type II cells (ATII cells). Total lung cells were first precultured, from which the Sca‐1+CD45−CD31− population was purified using fluorescence activated cell sorting (FACS). By these methods, it would seem that the Sca‐1+CD45−CD31− cells were LR‐MSCs. Similar to bone marrow derived mesenchymal stem cells (BM‐MSCs), these cells express Sca‐1, CD29, CD90, CD44 and CD106, but not CD31 or CD45. They share the same gene expression file with the BM‐MSCs and have a similar DNA content during long‐term culturing. Furthermore, they could be serially passaged with all these properties being sustained. Above all, LR‐MSCs could differentiate into ATII cells when co‐cultured with ATII cells in a trans‐well system. These findings demonstrated that the Sca‐1+CD45−CD31− cells appear to be LR‐MSCs that can differentiate into ATII cells. This approach may hold promise for their use in the treatment of lung disease.
Percutaneous coronary intervention in a 3‐year‐old with hypoplastic left heart syndrome
Authors: Noonan P.M.E. , Taliotis D. , Alahmar A.
Published: January 2014

Mortality outcomes associated with surgical palliation for hypoplastic left heart syndrome (HLHS) have continued to improve with time. Despite these advances, interstage mortality continues to be difficult to predict and prevent. This case report details a 3‐year‐old boy with HLHS palliated with a Glenn shunt who presented with acute myocardial infarction due to near total occlusion of the distal right coronary artery. He was treated by thrombus aspiration with good clinical response. This is the first report of thrombus aspiration in complex pediatric congenital heart disease and demonstrates the utility of collaboration between congenital and adult cardiologists. © 2015 Wiley Periodicals, Inc.
Structure of NADH‐Dependent Carbonyl Reductase (CPCR2) from Candida parapsilosis Provides Insight into Mutations that Improve Catalytic Properties
Authors: Man Henry , Loderer Christoph , Ansorge‐Schumacher Marion B. , Grogan Gideon
Published: January 2014

The (S)‐selective carbonyl reductase CPCR2 from Candida parapsilosis is a member of the medium‐chain reductase family of enzymes and is a useful biocatalyst for the reduction of prochiral ketone substrates. The structure of CPCR2 was determined in complex with the cofactor NADH [NADH=reduced form of nicotinamide adenine dinucleotide (NAD+)] to a resolution of 2.05 Å. Two dimers formed a tetramer in the asymmetric unit, but solution studies confirmed that a dimer was the predominant species in solution. In the monomer, the NADH cofactor is bound at the interface between the nucleotide binding domain and the catalytic domain, and the Re‐face hydride of the nicotinamide ring is presented to a hydrophobic binding pocket featuring the Leu262, Phe285, Trp286, Trp116, Leu119, Leu55 and Val50 residues, which leads to the surface of the enzyme. The catalytic zinc and coordinating amino acid side chains were observed in different conformations in the different monomers. In three out of four monomers, the zinc was coordinated by His65, Asp154, Glu66 and a water molecule; in the other subunit, an alternative coordination sphere, consisting of His65, Asp154, Cys44 and a water molecule, was observed. The change in coordination was accompanied by a movement of a mobile region of the protein chain between residues 43 and 63, which bears Cys44. The structure of CPCR2 provides further evidence of a dynamic coordination sphere for zinc in medium‐chain reductase dependent catalysis. It also sheds light on previous engineering studies on CPCR2 that were performed in the absence of structural data and provides a robust and reliable new model for further experiments directed towards improvement or alteration of CPCR2 activity.
Propane‐1,2‐diols from Dilactides, Oligolactides, or Poly‐L‐lactic Acid (PLLA): From Plastic Waste to Chiral Bulk Chemicals
Authors: Shuklov Ivan A. , Dubrovina Natalia V. , Schulze Joachim , Tietz Wolfgang , Kühlein Klaus , Börner Armin
Published: January 2014

The preparation of racemic or enantioenriched propane‐1,2‐diol from dilactides, oligolactides, or poly‐L‐lactic acid (PLLA) is described. The transformation is carried out as tandem reactions in MeOH, covering hydrolysis and subsequent hydrogenation by using copper chromite as a catalyst. The starting material present undesired side products of the PLLA synthesis or PLLA waste.
2,5‐Difluorenyl‐Substituted Siloles for the Fabrication of High‐Performance Yellow Organic Light‐Emitting Diodes
Authors: Chen Bin , Jiang Yibin , Chen Long , Nie Han , He Bairong , Lu Ping , Sung Herman H. Y. , Williams Ian D. , Kwok Hoi Sing , Qin Anjun , Zhao Zujin , Tang Ben Zhong
Published: January 2014

2,3,4,5‐Tetraarylsiloles are a class of important luminogenic materials with efficient solid‐state emission and excellent electron‐transport capacity. However, those exhibiting outstanding electroluminescence properties are still rare. In this work, bulky 9,9‐dimethylfluorenyl, 9,9‐diphenylfluorenyl, and 9,9′‐spirobifluorenyl substituents were introduced into the 2,5‐positions of silole rings. The resulting 2,5‐difluorenyl‐substituted siloles are thermally stable and have low‐lying LUMO energy levels. Crystallographic analysis revealed that intramolecular π–π interactions are prone to form between 9,9′‐spirobifluorene units and phenyl rings at the 3,4‐positions of the silole ring. In the solution state, these new siloles show weak blue and green emission bands, arising from the fluorenyl groups and silole rings with a certain extension of π conjugation, respectively. With increasing substituent volume, intramolecular rotation is decreased, and thus the emissions of the present siloles gradually improved and they showed higher fluorescence quantum yields (ΦF=2.5–5.4 %) than 2,3,4,5‐tetraphenylsiloles. They are highly emissive in solid films, with dominant green to yellow emissions and good solid‐state ΦF values (75–88 %). Efficient organic light‐emitting diodes were fabricated by adopting them as host emitters and gave high luminance, current efficiency, and power efficiency of up to 44 100 cd m−2, 18.3 cd A−1, and 15.7 lm W−1, respectively. Notably, a maximum external quantum efficiency of 5.5 % was achieved in an optimized device.
Towards Eumelanin@Zeolite Hybrids: Pore‐Size‐Controlled 5,6‐Dihydroxyindole Polymerization
Authors: Prasetyanto Eko Adi , Manini Paola , Napolitano Alessandra , Crescenzi Orlando , d'Ischia Marco , De Cola Luisa
Published: January 2014

5,6‐Dihydroxyindole (1) and its N‐methyl derivative (2), key eumelanin building blocks, were inserted into zeolite L by sublimation at 175 °C for 5 days. At a 10 mg/300 mg indole/zeolite ratio, the resulting hybrids displayed a stable deep red coloration. CP/MAS 13C NMR and UV/Vis spectroscopy of the red species suggested the generation and accommodation of quinonoid biindole derivative(s) within the void space of the acidic zeolite channels. Removal of the zeolite matrix by treatment with HF gave a stable species that could be separated by HPLC and characterized by mass spectrometry as an oxygenated biindole derivative (or a mixture of isomers), suggesting addition of water to the original dimer and subsequent re‐oxidation. The characterization was corroborated by optimized molecular geometries and simulated UV spectra with density functional calculations. Loading 1 or 2 into the larger pores of SBA‐15 type mesoporous silica resulted in black eumelanin‐type polymers, confirming channel size dependence over the polymerization process.
Unraveling the Crystal Structure of Lanthanide–Murexide Complexes: Use of an Ancient Complexometry Indicator as a Near‐Infrared‐Emitting Single‐Ion Magnet
Authors: Yi Xiaohui , Bernot Kevin , Le Corre Vincent , Calvez Guillaume , Pointillart Fabrice , Cador Olivier , Le Guennic Boris , Jung Julie , Maury Olivier , Placide Virginie , Guyot Yannick , Roisnel Thierry , Daiguebonne Carole , Guillou Olivier
Published: January 2014

Herein, we provide some structural evidence of the complexation color‐change of murexide solutions in presence of lanthanide, which has been used for decades in complexometric studies. For Ln=Sm to Lu and Y, the compounds crystallize as monomeric [Ln(Murex)3]⋅11 H2O with an N3O6 tricapped square‐antiprism environment, which are stable up to 250 °C. Single‐ion magnet (SIM) behavior is then observed on the YbIII derivative in an original nine‐coordinated environment. In‐field slow relaxation (Δ=(15.6±1) K; τ0=2.73×10−6 s) is observed with a very narrow distribution of the relaxation time (αmax=0.09). Magnetic and photophysical properties can be correlated. On one hand the analysis of NIR emission spectrum permits to have access to crystal field parameters and to compare them with those extracted from dc measurements. On the other hand, magnetic measurements permit to identify the nature of the MJ states involved in the 2F5/2→2F7/2 luminescence spectrum. The gap between the low‐lying states is in agreement with the energy barrier obtained from magnetic slow‐relaxation measurement.
Arsenic Removal by Adsorptive Flotation Methods
Authors: Yenial Ünzile , Bulut Gülay , Ali Sirkeci Ayhan
Published: January 2014

Arsenic being one of the major pollutants was removed from dilute aqueous solution by Adsorbing colloid flotation (ACF) and adsorption onto natural goethite. Flotation was subsequently applied as an effective solid/liquid separation method. The ACF tests showed that acidic aqueous medium (pH 5.5) favored the removal of As(V). Natural goethite was also found to be a good adsorbent for arsenic removal at pH 3. The optimum conditions were tested on process water and it was found that the residual arsenic content was lowered below 0.1 ppm with ACF and 0.2 ppm with adsorptive flotation.
Microfluidic Design of Complex Emulsions
Authors: Choi Chang‐Hyung , Kim Jongmin , Nam Jin‐Oh , Kang Sung‐Min , Jeong Seong‐Geun , Lee Chang‐Soo
Published: January 2014

Controllable generation of complex emulsions comprising exceptional features such as several compartments and shape anisotropy is becoming increasingly important. Complex emulsions are attracting great interest due to their significant potential in many applications, including foods, pharmaceuticals, cosmetics, materials, and chemical separations. Microfluidics is emerging as a promising route to the generation of complex emulsions, providing precise control over emulsion shape, size, and compartments. The aim of this Minireview is to mainly describe the progress of microfluidic approaches to design complex emulsions using hydrodynamic control and phase separation. The emulsions formed are classified according to their morphology, anisotropy, and internal structure. Emerging applications of complex emulsions formed using these microfluidic techniques are discussed.
Highly Coke‐Resistant Ni Nanoparticle Catalysts with Minimal Sintering in Dry Reforming of Methane
Authors: Han Joung Woo , Kim Chanyeon , Park Jun Seong , Lee Hyunjoo
Published: January 2014

Nickel catalysts are typically used for hydrogen production by reforming reactions. Reforming methane with carbon dioxide, called dry reforming of methane (DRM), is a good way to produce hydrogen or syngas (a mixture of hydrogen and carbon monoxide) from two notable greenhouse gases. However, Ni catalysts used for DRM suffer from severe coke deposition. It has been known that small Ni nanoparticles are advantageous to reduce coke formation, but the high reaction temperature of DRM (800 °C) inevitably induces aggregation of the nanoparticles, leading to severe coke formation and degraded activity. Here, we develop highly coke‐resistant Ni catalysts by immobilizing premade Ni nanoparticles of 5.2 nm in size onto functionalized silica supports, and then coating the Ni/SiO2 catalyst with silica overlayers. The silica overlayers enable the transfer of reactants and products while preventing aggregation of the Ni nanoparticles. The silica‐coated Ni catalysts operate stably for 170 h without any degradation in activity. No carbon deposition was observed by temperature programmed oxidation (TPO), transmission electron microscopy (TEM), X‐ray diffraction (XRD), and Raman spectroscopy. The Ni catalysts without silica coating show severe sintering after DRM reaction, and the formation of filamentous carbon was observed. The coke‐resistant Ni catalyst is potentially useful in various hydrocarbon transformations.
Optimized Synthesis and Antimalarial Activity of 1,2‐Dioxane‐4‐carboxamides
Authors: Lombardo Marco , Sonawane Dhiraj P. , Quintavalla Arianna , Trombini Claudio , Dhavale Dilip D. , Taramelli Donatella , Corbett Yolanda , Rondinelli Francesca , Fattorusso Caterina , Persico Marco , Taglialatela‐Scafati Orazio
Published: January 2014

We recently proposed 3‐methoxy‐4‐methoxycarbonyl‐1,2‐dioxanes 3 as promising scaffolds enabling access to potential antimalarial drugs. We present here an optimized two‐step synthesis of 3 characterized by high yields, simple work‐up procedures and high diastereoselectivity allowing us to readily prepare 3 on multigram scale. The versatility of the 1,2‐dioxane scaffold was demonstrated by our generation of a new family of 1,2‐dioxane‐4‐carboxamides 8a–h and the realization of their in vitro activities against chloroquine‐sensitive (D10) and chloroquine‐resistant (W2) P. falciparum strains. In particular, one of these amides (8e), displayed antimalarial activity on par with the natural product lead plakortin and was 5‐fold more active than its methyl ester analogue 3. Structure–activity relationship (SAR) analysis supported by DFT calculations revealed that, for this family of compounds, alkyl substituents at C6 dictate, in large part, the degree of antimalarial activity. This finding contrasts those previously observed for the ester series.
Molecular Design Exploiting a Fluorine gauche Effect as a Stereoelectronic Trigger
Authors: Rey Yannick P. , Zimmer Lucie E. , Sparr Christof , Tanzer Eva‐Maria , Schweizer W. Bernd , Senn Hans Martin , Lakhdar Sami , Gilmour Ryan
Published: January 2014

Acyclic conformational control often relies on destabilising noncovalent interactions to give rise to predictable conformer populations. Pertinent examples of such strategies include allylic strain (A1,2 and A1,3) and syn‐pentane interactions. However, the incorporation of fluorine vicinal to an electron‐withdrawing group (F–Cβ–Cα–X) can lead to predictable conformations as a consequence of stabilising hyperconjugative and/or electrostatic interactions. Herein, we describe the application of a fluorine gauche effect to predictably control torsional rotation in a class of fluorinated 4‐(dimethylamino)pyridine (DMAP) analogues. Intramolecularisation, such as protonation or acylation, generates an electropositive nitrogen centre vicinal to the fluorine atom at a molecular hinge (F–Cβ–Cα–N+); this is the only rotatable sp3–sp3 bond. In so doing, this “substrate binding” triggers a conformational change akin to the induced fit process inherent to enzymatic systems. Herein, we validate this design approach to control molecular space. A number of X‐ray structures are documented that display this gauche preference (φNCCF ≈ 60°). Preliminary catalysis experiments are disclosed together with a kinetic and reactivity analysis.
Multiparameter cartographic assessment of the hydrochemical groundwater of the Soummam valley (Kabylia, Algeria)
Authors: Semar Ahcène , Saibi Hakim
Published: January 2014

A hydrochemical survey based on an analysis of groundwater data was undertaken in the alluvial aquifer of the lower valley of Soummam (LVS). The LVS reservoir is characterized by a hydrogeologically heterogeneous lithology consisting of gravel, sand, and silt (with occasionally significant levels of clay). Numerous contacts and faults affect the region. Data were derived from a hydrochemical analysis of water by titration and spectrophotometry using 60 groundwater samples. Factor analysis with varimax rotation was applied to these data to reduce their size and to understand the nature of ion associations. The results of this analysis were used for Kriging mapping to pinpoint hydrochemical features of the study area. Four factors explaining ∼92% of the data variability were identified: one related to sodium–potassium (Na‐K), chloride (Cl), and magnesium (Mg); one related to nitrates (NO3); one related to bicarbonate (HCO3); and one related to calcium (Ca) and sulfate (SO4). © 2014 American Institute of Chemical Engineers Environ Prog, 33: 1357–1365, 2014
Nondestructive analysis of jade artifacts from the Cemetery of the Ying State in Henan Province, China using confocal Raman microspectroscopy and portable X‐ray fluorescence spectroscopy
Authors: Zhao H. X. , Li Q. H. , Liu S. , Hu Y. Q. , Gan F. X.
Published: January 2014

Confocal Raman microspectroscopy and portable X‐ray fluorescence spectroscopy were used nondestructively to characterise 18 intact jade artifacts from the Cemetery of the Ying State in Pingdingshan, Henan Province, China. These jade artifacts date from the early to the middle of the Western Zhou Period (the mid‐11th to the mid‐9th century BC). Thirteen jade artifacts made of tremolite and two jade artifacts made of actinolite were discriminated from each other by their hydroxyl stretching modes, and a malachite pendant, a muscovite dagger‐axe, and a crystal pendant were also identified. Black graphite was analysed in three jade artifacts composed of tremolite, and the mineralization temperatures were estimated and compared. A red powder was found on the surface of all of the jade artifacts, and this was found to be cinnabar (HgS), which is thought to have been added to the tomb environments during burial ceremonies. The chemical compositions and the possible provenances of the jade artifacts are briefly discussed. Copyright © 2014 John Wiley & Sons, Ltd.
A finite strain closed‐form solution for the elastoplastic ground response curve in tunnelling
Authors: Vrakas Apostolos , Anagnostou Georgios
Published: January 2014

The ground response to tunnel excavation is usually described in terms of the characteristic line of the ground (also called ‘ground response curve’, GRC), which relates the support pressure to the displacement of the tunnel wall. Under heavily squeezing conditions, very large convergences may take place, sometimes exceeding 10–20% of the excavated tunnel radius, whereas most of the existing formulations for the GRC are based on the infinitesimal deformation theory. This paper presents an exact closed‐form analytical solution for the ground response around cylindrical and spherical openings unloaded from isotropic and uniform stress states, incorporating finite deformations and linearly elastic‐perfectly plastic rock behaviour obeying the Mohr–Coulomb failure criterion with a non‐associated flow rule. Additionally, the influence of out‐of‐plane stress in the case of cylindrical cavities under plane‐strain conditions is examined. The solution is presented in the form of dimensionless design charts covering the practically relevant parameter range. Finally, an application example is included with reference to a section of the Gotthard Base tunnel crossing heavily squeezing ground. The expressions derived can be used for preliminary convergence assessments and as valuable benchmarks for finite strain numerical analyses. Copyright © 2014 John Wiley & Sons, Ltd.
Synthesis and characterization of novel pH‐sensitive chitosan‐poly(acrylamide‐co‐itaconic acid) hydrogels
Authors: Bocourt Michel , Bada Nancy , Acosta Niuris , Bucio Emilio , Peniche Carlos
Published: January 2014

Novel pH‐sensitive chitosan‐poly(acrylamide‐co‐itaconic acid) hydrogels were prepared by free radical copolymerization of acrylamide and itaconic acid (IA) in chitosan solution. The hydrogels were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry and the swelling ratios of the hydrogels in water (pH 6.8) and pH 1.2. The influence of composition on the thermal properties of the hydrogels was assessed. The glass transition temperatures of the samples increased with IA content, ranging from 110 to 136 °C. Swelling of the hydrogels was found to obey second‐order kinetics with respect to the remnant swelling, indicating that diffusion is controlled by the relaxation of chains. The equilibrium swelling degree was strongly dependent on pH and composition. At both pH values the highest water uptake was obtained for the IA‐free sample M1. From the equilibrium swelling results the average molar mass between crosslinks, Mc, and the crosslink density of the chitosan‐poly(acrylamide‐co‐itaconic acid) samples were calculated. The results evidenced the reinforcing effect of IA on the hydrogel structure. It is concluded that these highly swellable pH‐sensitive hydrogels can be useful for applications in biomedicine and pharmacy. © 2013 Society of Chemical Industry
Using Systemability Function for Periodic Replacement Policy in Real Environments
Authors: Sgarbossa Fabio , Persona Alessandro , Pham Hoang
Published: January 2014

In the last decades, various maintenance policies have been developed and widely used, including, but not limited to replacement policy and preventive maintenance policy, depending on an accurate estimation of the reliability and the failure intensity functions. Many studies, yet, haven't considered the environmental factors (EFs) and their effects on the survival distribution of operating units. This paper is a following up with our recent research about environmental impacts on preventive maintenance by investigating the periodic replacement policy using a systemability approach. The differences between the classical maintenance approach and the systemability approach have been investigated and applied to a real industrial setting to evaluate the importance and the relevance of taking into account EFs in the implementation of one maintenance policy versus another. Copyright © 2014 John Wiley & Sons, Ltd.

Highlights

This research investigates the impacts of different operational environments in periodic replacement policy, using a new concept called systemability.

New mathematical formulations for periodic replacement policy have been introduced and applied to real case studies.

Comparison between classical approach and new approach allows to validate the use of systemability and to quantify the impact of operational conditions on total cost.
Recent findings on erasure codes for space communications
Authors: Garrammone Giuliano , De Cola Tomaso , Matuz Balázs , Liva Gianluigi
Published: January 2014

Implementation of automatic repeat request strategies is the main reliability option available in the Consultative Committee for Space Data Systems protocols to support data communications in deep‐space missions. The large latency often experienced in such scenarios, however, penalizes the efficiency of retransmissions, making the overall applicability of automatic repeat request problematic. On the contrary, the use of erasure codes is a more appealing solution to mitigate packet losses. In this regard, preliminary studies on the use of binary low‐density parity‐check codes under maximum likelihood/iterative decoding have already shown the performance benefit they can bring with respect to traditional schemes based on retransmissions. This paper extends the analysis conducted in previous studies toward non‐binary low‐density parity‐check codes. Performance assessment is carried out with respect to reliability metrics (codeword error rate) and encoding/decoding complexity. Finally, the integration of erasure codes into the Consultative Committee for Space Data Systems protocol stack is discussed, by presenting the implementation in the Licklider Transmission Protocol. Copyright © 2014 John Wiley & Sons, Ltd.
Net time‐dependent ROC curves: a solution for evaluating the accuracy of a marker to predict disease‐related mortality
Authors: Lorent Marine , Giral Magali , Foucher Yohann
Published: January 2014

Developing prognostic markers of mortality for patients with chronic disease is important for identifying subjects at high risk of death and optimizing medical management. The usual approach in this regard is the use of time‐dependent ROC curves, which are well adapted for censored data. Nevertheless, an important part of the mortality may not be due to the chronic disease, and it is often impossible to individually determine whether or not the deaths are related to the disease itself. In survival regression, one solution is to distinguish between the expected mortality of one general population (from life tables) and the excess mortality related to the disease, by using an additive relative survival model. In this paper, we propose a new estimator of time‐dependent ROC curves, which includes this concept of net survival, in order to evaluate the capacity of a marker to predict disease‐specific mortality. We performed simulations in order to validate this estimator. We also illustrate this method using two different applications: (i) predicting mortality related to primary biliary cirrhosis of the liver and (ii) predicting mortality related to kidney transplantation in end‐stage renal disease patients. For each application, we evaluated a scoring system already established. The results demonstrate the utility of the proposed estimator of net time‐dependent ROC curves. Copyright © 2014 John Wiley & Sons, Ltd.
Least angle regression for model selection
Authors: Zhang Hongyang , Zamar Ruben H.
Published: January 2014

Model selection using least angle regression (LARS) is an interesting approach proposed by Efron B, Hastie T, Johnstone L, Tibshirani R. Least angle regression.The Annals of statistics2004, 320:407–499. In this paper we first review theLARSalgorithm and its relationships with other popular methods such as stagewise regression and the lasso. Then we conduct a survey of recent developments and extensions ofLARS.WIREs Comput Stat2014, 6:116–123. doi: 10.1002/wics.1288

This article is categorized under:

Statistical Learning and Exploratory Methods of the Data Sciences > Modeling Methods

Statistical Models > Model Selection

Statistical and Graphical Methods of Data Analysis > Modeling Methods and Algorithms

Statistical Models > Linear Models
eIF5A and EF‐P: two unique translation factors are now traveling the same road
Authors: Rossi Danuza , Kuroshu Reginaldo , Zanelli Cleslei Fernando , Valentini Sandro Roberto
Published: January 2014

Translational control is extremely important in all organisms, and some of its aspects are highly conserved among all primary kingdoms, such as those related to the translation elongation step. The previously classified translation initiation factor 5A (eIF5A) and its bacterial homologue elongation factor P (EF‐P) were discovered in the late 70's and have recently been the object of many studies. eIF5A and EF‐P are the only cellular proteins that undergo hypusination and lysinylation, respectively, both of which are unique posttranslational modifications. Herein, we review all the important discoveries related to the biochemical and functional characterization of these factors, highlighting the implication of eIF5A in translation elongation instead of initiation. The findings that eIF5A and EF‐P are important for specific cellular processes and play a role in the relief of ribosome stalling caused by specific amino acid sequences, such as those containing prolines reinforce the hypothesis that these factors are involved in specialized translation. Although there are some divergences between these unique factors, recent studies have clarified that they act similarly during protein synthesis. Further studies may reveal their precise mechanism of ribosome activity modulation as well as the mRNA targets that require eIF5A and EF‐P for their proper translation. WIREs RNA 2014, 5:209–222. doi: 10.1002/wrna.1211

This article is categorized under:

Translation > Translation Mechanisms

Translation > Translation Regulation
A Systematic Review on the Effectiveness of Tai Chi Exercise in Individuals with Parkinson's Disease from 2003 to 2013*
Authors: Toh Sharon Fong Mei
Published: January 2014

Objective/Background

This study aims to review the current evidence on the effectiveness of Tai Chi exercise in individuals with Parkinson's disease (PD) in the past 10 years.

Methods

A systematic review of studies published in English from 2003 to 2013, retrieved from three electronic databases—MEDLINE, Cumulative Index to Nursing and Allied Health Literature, and ScienceDirect—was performed. The review selected only those studies that investigated the effects of Tai Chi exercise on individuals with PD and had a full-length publication. Methodological qualities of the randomized control trials were appraised based on the modified Jadad scale.

Results

Of the 702 articles, eight publications, including four randomized controlled trials, two single-arm intervention studies, and two case reports, were reviewed. Results of this review show that there is an inconsistency of strong empirical evidence to support the efficacy of Tai Chi exercise in the PD population. Furthermore, this review reveals that there is a lack of scientific rigor in the experimental designs of the trials conducted to examine the effects of Tai Chi intervention on the PD population.

Conclusion

Because of the small sample and inconclusive results, this review cannot provide a firm conclusion to support or refute the effectiveness of Tai Chi in improving motor or nonmotor performance in patients with PD. Further research is required to investigate whether there are specific benefits of Tai Chi for people with PD in these areas and future review should include non-English studies, which examine the use of Tai Chi with this type of population.
“We Have Never Known What Death Was Before” U.S. History Textbooks and the Civil War
Authors: Pearcy Mark
Published: January 2014

Textbooks are a significant element of the social studies curriculum and teacher pedagogical choice (Apple, 2004; Apple & Christian-Smith, 1991). Students’ views of American history are dramatically affected by the textbook narratives to which they are exposed, and teachers often tilt their curricular choices based on the textbooks available to them ( Luke, 2006 Schug, Western & Enochs, 1997 ). The history of our nation's armed conflicts is often presented, through our textbooks and our pedagogy, as a history of reluctant violence, which promotes a particular moral agenda that exerts control over our students’ future beliefs and decisions. This is particularly important with regard to our textbook depictions of the U.S. Civil War, which holds a curricular status as a necessary and moral conflict. This study examines the manner in which U.S. history textbooks present the U.S. Civil War, as compared to relevant historiography, and presents recommendations for how teachers may approach the moral realities of war with their students.
Symptomatic Hypotonic Hyponatremia Presenting at High Altitude
Authors: Spano Susanne J. , Reagle Zacharia , Evans Timothy
Published: January 2014

We present a case of altered mental status and seizure that occurred at an altitude known to cause high altitude-related illnesses. Based on the presenting symptoms, the patient was initially transferred to the hospital with a presumptive diagnosis of high altitude cerebral edema. On review of imaging and laboratory data, she was found to be experiencing symptomatic hypotonic hyponatremia. This case presented an interesting diagnostic challenge and underscores the importance of maintaining a broad differential diagnosis when evaluating a patient with altered mental status from an alpine setting.