bluuebunny/crossref_metadata_2025 huggingface dataset:
The Behaviour of Recycled Material with Particles of Various Sizes of Polyamide 6 to Micro Hardness
Authors: Senkerik Vojtech , Stanek Michal , Manas David , Manas Miroslav , Skrobak Adam , Ovsik Martin
Published: September 2015

Every manufacture of any plastic parts produces some waste, such as defective injects or cold runner system from injection molding technology. This waste can be directly used several times. But when size of this material is reduced, particles of different sizes are made. From large particles similar to the original granulate material, to dust particles. This size variation can cause problems during subsequent processing. These particles of different size have distinct melting rate. That can cause an inhomogeneity of a melt and diverse structure of solidified polymer. This research paper studies the influence of the particle size of recycled polymeric material on the micro harness properties of semi-crystalline polyamide 6 at room temperature.
Behavior of Glued Connections under Shear Loading
Authors: Machalická Klára , Eliášová Martina
Published: September 2015

An intensive research in load-bearing glass structures leads to the requirement for performing glass-to-glass or glass-to-different material connections. Glued shear connection is suitable for these applications mainly due to its uniform stress distribution in larger area in comparison with bolted connections. The reliability of adhesive in the connection during the life time of a structure is affected by many factors, [1], [2], [3], [4]. The article deals with the experimental analysis focused on the determination of material characteristics of adhesives in planar connections, it describes the effect of various factors on the behavior of an adhesive joint under increasing shear loads, its ultimate load-bearing capacity and its failure modes. The main investigated factors are the type of adhesive, the type of connected materials (material of substrate), surface treatment and the thickness of the adhesive layer. Due to importance of adhesive layer thickness especially in rigid and semi-rigid glues, numerical models responding to the effect of thickness was carried out.
Plastic Zone around a Fatigue Crack Determined by the FEM and a Nanoindentation Technique
Authors: Materna Aleš , Ondráček Jan
Published: September 2015

Plastic zone around a fatigue crack in AISI 304 stainless steel was studied experimentally using nanoindentation and numerically by the finite element analysis. Results obtained from one experimental observation of crack propagating under constant amplitude loading showed that nanohardness can be correlated to strain hardening caused by the cyclic deformation in the vicinity of the crack. However, for the material chosen for this study, exact plastic zone shape is hard to evaluate due to the scattering of experimental results.
Ecosystem regimes and responses in a coupled ancient lake system from MIS 5b to present: the diatom record of lakes Ohrid and Prespa
Authors: Cvetkoska A. , Jovanovska E. , Francke A. , Tofilovska S. , Vogel H. , Levkov Z. , Donders T. H. , Wagner B. , Wagner-Cremer F.
Published: September 2015

Abstract. In order to understand the panarchy and interactions since the last interglacial period in the oldest, most diverse and hydrologically connected European lake system, we assess changes in the diatom record and selected geochemistry data from Lake Ohrid's "DEEP site" core and compare it with the diatom and multi-proxy data from Lake Prespa core Co1215. Driven by climate forcing, tephra impact and/or human influence, the lakes experienced two adaptive cycles during the last 92 ka: "interglacial and interstadial-regime" and "glacial-regime". The patterns of regime shifts appear synchronous in both lakes, while differences occur in the inferred amplitudes of the variations. The deeper Lake Ohrid shifted between ultraoligo- and oligotrophic regimes in contrast to the more shallow Lake Prespa, which shifts from (oligo-) mesotrophic to eutrophic conditions. In response to external forcing, Lake Ohrid exhibits a high capacity to buffer disturbances, whereas Lake Prespa is much more resilient and "recovers" in relatively short time. This decoupling of the response is evident during the MIS 5/4 and 2/1 transitions, when Lake Ohrid displays prolonged and gradual changes. The lakes' specific differences in the response and feedback mechanisms and their different physical and chemical properties, probably confine a direct influence of Lake Prespa's shallow/eutrophic regimes over the productivity regimes of Lake Ohrid. Regime shifts of Lake Ohrid due to the hydrological connectivity with Lake Prespa are not evident in the data presented here. Moreover, complete ecological collapse did not happened in both lakes for the period presented in the study.
Understanding land surface response to changing South Asian monsoon in a warming climate
Authors: Ramarao M. V. S , Krishnan R. , Sanjay J. , Sabin T. P.
Published: September 2015

Abstract. Recent studies have drawn attention to a significant weakening trend of the South Asian monsoon circulation and an associated decrease in regional rainfall during the last few decades. While surface temperatures over the region have steadily risen during this period, most of the CMIP (Coupled Model Intercomparison Project) global climate models have difficulties in capturing the observed decrease of monsoon precipitation, thus limiting our understanding of the regional land surface response to monsoonal changes. This problem is investigated by performing two long-term simulation experiments, with and without anthropogenic forcing, using a variable resolution global climate model having high-resolution zooming over the South Asian region. The present results indicate that anthropogenic effects have considerably influenced the recent weakening of the monsoon circulation and decline of precipitation. It is seen that the simulated increase of surface temperature over the Indian region during the post-1950s is accompanied by a significant decrease of monsoon precipitation and soil moisture. Our analysis further reveals that the land surface response to decrease of soil moisture is associated with significant reduction in evapotranspiration over the Indian land region. A future projection, based on the representative concentration pathway 4.5 (RCP4.5) scenario of the Intergovernmental Panel on Climate Change (IPCC), using the same high-resolution model indicates the possibility for detecting the summer-time soil drying signal over the Indian region during the 21st century in response to climate change. Given that these monsoon hydrological changes have profound socio-economic implications the present findings provide deeper insights and enhance our understanding of the regional land surface response to the changing South Asian monsoon. While this study is based on a single model realization, it is highly desirable to have multiple realizations to establish the robustness of the results.
The transient variation in the complexes of the low-latitude ionosphere within the equatorial ionization anomaly region of Nigeria
Authors: Rabiu A. B. , Ogunsua B. O. , Fuwape I. A. , Laoye J. A.
Published: September 2015

Abstract. The quest to find an index for proper characterization and description of the dynamical response of the ionosphere to external influences and its various internal irregularities has led to the study of the day-to-day variations of the chaoticity and dynamical complexity of the ionosphere. This study was conducted using Global Positioning System (GPS) total electron content (TEC) time series, measured in the year 2011, from five GPS receiver stations in Nigeria, which lies within the equatorial ionization anomaly region. The non-linear aspects of the TEC time series were obtained by detrending the data. The detrended TEC time series were subjected to various analyses to obtain the phase space reconstruction and to compute the chaotic quantifiers, which are Lyapunov exponents LE, correlation dimension, and Tsallis entropy, for the study of dynamical complexity. Considering all the days of the year, the daily/transient variations show no definite pattern for each month, but day-to-day values of Lyapunov exponents for the entire year show a wavelike semiannual variation pattern with lower values around March, April, September and October. This can be seen from the correlation dimension with values between 2.7 and 3.2, with lower values occurring mostly during storm periods, demonstrating a phase transition from higher dimension during the quiet periods to lower dimension during storms for most of the stations. The values of Tsallis entropy show a similar variation pattern to that of the Lyapunov exponent, with both quantifiers correlating within the range of 0.79 to 0.82. These results show that both quantifiers can be further used together as indices in the study of the variations of the dynamical complexity of the ionosphere. The presence of chaos and high variations in the dynamical complexity, even in quiet periods in the ionosphere, may be due to the internal dynamics and inherent irregularities of the ionosphere which exhibit non-linear properties. However, this inherent dynamics may be complicated by external factors like geomagnetic storms. This may be the main reason for the drop in the values of the Lyapunov exponent and Tsallis entropy during storms. The dynamical behaviour of the ionosphere throughout the year, as described by these quantifiers, was discussed in this work.
Génesis de la formación permanente del profesorado de Educación Física
Authors: Da Cruz Murta Luis Manuel , Fernández-Truan Juan Carlos , Sáenz-López Buñuel Pedro
Published: September 2015

El presente artículo trata de realizar una revisión histórica sobre los inicios de la formación permanente del profesorado de educación física en España y más concretamente en el ámbito de la Comunidad Autónoma Andaluza, como uno de los elementos fundamentales de la mejora de la calidad docente en los actuales sistemas educativos. Para ello, se realiza una profunda revisión legislativa desde los primeros intentos de actualización y formación del profesor del siglo XVIII hasta los cambios educativos surgidos hasta después de la Guerra Civil Española. Las conclusiones han demostrado que aunque los docentes de Gimnasia (Educación Física actual) siempre tuvieron un tratamiento y consideración especial que les diferenciaba del resto de docentes de otras materias, en contra de lo que se podía pensar, siempre han estado presentes desde el inicio de las actividades de Formación Permanente, en las diferentes propuestas de actividades para poder mejorar su docencia e incrementar la consideración social de esta materia, como una parte importante de los diferentes planes de estudio.
Vulvodynia Treated Successfully with Breathing Biofeedback and Integrated Stress Reduction: A Case Report
Authors: Peper Erik , Aranda Pamela Martinez , Moss Donald
Published: September 2015

Millions of women experience substantial pain and suffering from vulvodynia, which is pain around the entrance to the vagina (vulva). A common treatment is surgical removal of the tissue (vestibulectomy). This case report describes the detailed process of a holistic biofeedback-based intervention that successfully resolved the vulvodynia in a 23-year-old woman. The four-session treatment interventions included teaching diaphragmatic breathing to transform shallow thoracic breathing into slower diaphragmatic breathing. Treatment transformed her feeling of powerlessness, a belief that there was nothing she could do, into empowerment and a hope that she could reduce her symptoms and optimize her health. She also practiced self-healing imagery and learned to change her posture from collapsed to erect/empowered. Each time she felt discomfort or was fearful, her lower abdomen tended to tighten. After treatment, she used this sensation as a reminder to breathe lower and slower and sit or stand erect. After 6 weeks, she once again could initiate and enjoy intercourse and has been symptom free during the 8 month follow-up.
Prestart Psychophysiological Profile of a 200-m Canoe Athlete: A Comparison of Best and Worst Reaction Times
Authors: Christie Sommer , Werthner Penny
Published: September 2015

The difference between success and failure in 200-m canoe and kayak events is measured in milliseconds. The gold medal for the 200-m kayak in the Summer 2012 Olympic Games in London was won by a margin of 294 milliseconds, and the difference between winning a bronze medal and not reaching the podium was merely 31 milliseconds. In addition to physical fitness, strength, and technique, the ability to focus effectively and manage arousal is crucial to the ability to react quickly off the start. Conversely, the inability to manage arousal and focus has been shown to reduce reaction time (RT) and, in extreme cases, lead to “choking.” Research in sport psychology and psychophysiology has identified multiple psychological, physiological, and neurological characteristics that underlie peak performance. Although many of the skills and characteristics identified in the research are common to most peak performers, it is also well known that each athlete's optimal performance zone for competition is unique. For athletes, identifying these individual zones of optimal physical, psychological, physiological, and neurological functioning can be elusive and difficult to quantify. Existing technology in bio- and neurofeedback presents a unique opportunity for athletes and researchers to explore what individual peak performance looks like both physiologically and neurologically. Thus, the purpose of this case analysis was to explore the psychophysiological differences of a 200-m canoe athlete between his best and worst reaction times.
The nonlinear equation of state of sea water and the global water mass distribution
Authors: Nycander Jonas , Hieronymus Magnus , Roquet Fabien
Published: September 2015

The role of nonlinearities of the equation of state (EOS) of seawater for the distribution of water masses in the global ocean is examined through simulations with an ocean general circulation model with various manipulated versions of the EOS. A simulation with a strongly simplified EOS, which contains only two nonlinear terms, still produces a realistic water mass distribution, demonstrating that these two nonlinearities are indeed the essential ones. Further simulations show that each of these two nonlinear terms affects a specific aspect of the water mass distribution: the cabbeling term is crucial for the formation of Antarctic Intermediate Water and the thermobaric term for the layering of North Atlantic Deep Water and Antarctic Bottom Water.
Extreme wind‐ice interaction over Recovery Ice Stream, East Antarctica
Authors: Das Indrani , Scambos Ted A. , Koenig Lora S. , van den Broeke Michiel R. , Lenaerts Jan T. M.
Published: September 2015

Surface snow accumulation over East Antarctica is an important climate indicator but a difficult parameter to constrain. Surface mass ablation dominates over persistent wind‐scour zones as near‐surface katabatic winds accelerate over locally steeper ice surface topography, and sublimate and redistribute snow. Here we quantify ablation rates and downwind redeposition of snow over wind‐scour zones in the upper Recovery Ice Stream catchment. Airborne radio echo‐soundings show a gradual ablation of ~16–18 m of firn, corresponding to ~200 years of accumulation, over these zones and ablation rates of ~54 kg m−2 a−1 (54 mm water equivalent a−1). We conclude that mass loss is dominated by sublimation and mass is transported downwind as water vapor, because snow redeposition downslope of the wind‐scour zones constitutes only a small fraction (<10%) of the cumulative mass loss.
Limitations on silicon in the outer core: Ultrasonic measurements at high temperatures and high dK/dP values of Fe‐Ni‐Si liquids at high pressures
Authors: Williams Quentin , Manghnani Murli H. , Secco Richard A. , Fu Shunsheng
Published: September 2015

The sound velocities of four iron‐nickel‐silicon liquids (Fe‐5 wt %Ni‐6 wt %Si, Fe‐5 wt %Ni‐10 wt %Si, Fe‐5 wt %Ni‐14 wt %Si, and Fe‐5 wt %Ni‐20 wt %Si) are measured between 1460 and 1925 K at ambient pressures using ultrasonic interferometry. The results constrain both the dependence on Si content of the bulk modulus of these liquids and the temperature dependence of their elasticity. These elastic data are utilized to assess both relatively low pressure (to 12 GPa) compressional data on Fe‐Si liquids and to extrapolate to higher‐pressure and higher‐temperature conditions. If a single equation of state for Fe‐Ni‐Si liquids of a given composition applies from low pressure to near core conditions, then our results imply that the isothermal pressure derivative of the bulk modulus of these liquids is high: likely 8 and above at high temperatures. This high value of the pressure derivative of the bulk modulus at low pressures in Fe‐Si liquids causes marked stiffening at higher pressures, leading to notable incompressibility and apparent low values of the pressure derivative of the bulk modulus at core conditions. These results reinforce the conclusion that silicon is not a major alloying component of Earth's core.
Low‐cloud characteristics over the tropical western Pacific from ARM observations and CAM5 simulations
Authors: Chandra Arunchandra S. , Zhang Chidong , Klein Stephen A. , Ma Hsi‐Yen
Published: September 2015

This study evaluates the ability of the Community Atmospheric Model version 5 (CAM5) to reproduce low clouds observed by the Atmospheric Radiation Measurement (ARM) cloud radar at Manus Island of the tropical western Pacific during the Years of Tropical Convection. Here low clouds are defined as clouds with their tops below the freezing level and bases within the boundary layer. Low‐cloud statistics in CAM5 simulations and ARM observations are compared in terms of their general occurrence, mean vertical profiles, fraction of precipitating versus nonprecipitating events, diurnal cycle, and monthly time series. Other types of clouds are included to put the comparison in a broader context. The comparison shows that the model overproduces total clouds and their precipitation fraction but underestimates low clouds in general. The model, however, produces excessive low clouds in a thin layer between 954 and 930 hPa, which coincides with excessive humidity near the top of the mixed layer. This suggests that the erroneously excessive low clouds stem from parameterization of both cloud and turbulence mixing. The model also fails to produce the observed diurnal cycle in low clouds, not exclusively due to the model coarse grid spacing that does not resolve Manus Island. This study demonstrates the utility of ARM long‐term cloud observations in the tropical western Pacific in verifying low clouds simulated by global climate models, illustrates issues of using ARM observations in model validation, and provides an example of severe model biases in producing observed low clouds in the tropical western Pacific.
Proteoglycans and Acidic Polysaccharides Analysis
Authors: Lauder Robert M.
Published: September 2015

The study of the structure and function of proteoglycans (PGs) and glycosaminoglycans (GAGs) has assumed an increasing significance as the wide range of important biological processes in which they play central roles has been elucidated. As studies of GAG structure expand in scope, and detail, the full structural diversity of these polymers is being uncovered. Significant heterogeneity can be seen but relationships with development, age, and pathology are being uncovered, which place these macromolecules centrally in these processes.

Available methodologies allow detailed analysis of GAGs, but careful attention to the sample requirements of these methods and to their limitations is required to ensure the quality and reliability of the data derived is assured. Important developments, including mass spectrometry approaches, will take the field forward but well‐established methods for the isolation and characterization of these complex molecules continue to have a hugely important role to play in structural and functional studies.

This article examines a wide range of methodologies for the isolation and characterization of the PGs and GAGs in which recent developments in the field are reported along with well‐established methods for the characterization of entire GAG chains or discrete features within those.
Characterization of IgG4 anti‐neurofascin 155 antibody‐positive polyneuropathy
Authors: Ogata Hidenori , Yamasaki Ryo , Hiwatashi Akio , Oka Nobuyuki , Kawamura Nobutoshi , Matsuse Dai , Kuwahara Motoi , Suzuki Hidekazu , Kusunoki Susumu , Fujimoto Yuichi , Ikezoe Koji , Kishida Hitaru , Tanaka Fumiaki , Matsushita Takuya , Murai Hiroyuki , Kira Jun‐ichi
Published: September 2015

Objective

To investigate anti‐neurofascin 155 (NF155) antibody‐positive chronic inflammatory demyelinating polyneuropathy (CIDP).

Methods

Sera from 50 consecutive CIDP patients diagnosed in our clinic, 32 patients with multiple sclerosis, 40 patients with other neuropathies including 26 with Guillain–Barré syndrome (GBS)/Fisher syndrome, and 30 healthy controls were measured for anti‐NF antibodies by flow cytometry using HEK293 cell lines stably expressing human NF155 or NF186. Four additional CIDP patients with anti‐NF155 antibodies referred from other clinics were enrolled for clinical characterization.

Results

The positivity rate for anti‐NF155 antibodies in CIDP patients was 18% (9/50), who all showed a predominance of IgG4 subclass. No other subjects were positive, except one GBS patient harboring IgG1 anti‐NF155 antibodies. No anti‐NF155 antibody carriers had anti‐NF186 antibodies. Anti‐NF155 antibody‐positive CIDP patients had a significantly younger onset age, higher frequency of drop foot, gait disturbance, tremor and distal acquired demyelinating symmetric phenotype, greater cervical root diameter on magnetic resonance imaging neurography, higher cerebrospinal fluid protein levels, and longer distal and F‐wave latencies than anti‐NF155 antibody‐negative patients. Marked symmetric hypertrophy of cervical and lumbosacral roots/plexuses was present in all anti‐NF155 antibody‐positive CIDP patients examined by neurography. Biopsied sural nerves from two patients with anti‐NF155 antibodies demonstrated subperineurial edema and occasional paranodal demyelination, but no vasculitis, inflammatory cell infiltrates, or onion bulbs. Among anti‐NF155 antibody‐positive patients, treatment responders more frequently had daily oral corticosteroids and/or immunosuppressants in addition to intravenous immunoglobulins than nonresponders did.

Interpretation

Anti‐NF155 antibodies occur in a subset of CIDP patients with distal‐dominant involvement and symmetric nerve hypertrophy.
Hydrophobic Nanoreactor Soft‐Templating: A Supramolecular Approach to Yolk@Shell Materials
Authors: Guiet Amandine , Göbel Caren , Klingan Katharina , Lublow Michael , Reier Tobias , Vainio Ulla , Kraehnert Ralph , Schlaad Helmut , Strasser Peter , Zaharieva Ivelina , Dau Holger , Driess Matthias , Polte Jörg , Fischer Anna
Published: September 2015

Due to their unique morphology‐related properties, yolk@shell materials are promising materials for catalysis, drug delivery, energy conversion, and storage. Despite their proven potential, large‐scale applications are however limited due to demanding synthesis protocols. Overcoming these limitations, a simple soft‐templated approach for the one‐pot synthesis of yolk@shell nanocomposites and in particular of multicore metal nanoparticle@metal oxide nanostructures (MNP@MOx) is introduced. The approach here, as demonstrated for AuNP@ITOTR (ITOTR standing for tin‐rich ITO), relies on polystyrene‐block‐poly(4‐vinylpyridine) (PS‐b‐P4VP) inverse micelles as two compartment nanoreactor templates. While the hydrophilic P4VP core incorporates the hydrophilic metal precursor, the hydrophobic PS corona takes up the hydrophobic metal oxide precursor. As a result, interfacial reactions between the precursors can take place, leading to the formation of yolk@shell structures in solution. Once calcined these micelles yield AuNP@ITOTR nanostructures, composed of multiple 6 nm sized Au NPs strongly anchored onto the inner surface of porous 35 nm sized ITOTR hollow spheres. Although of multicore nature, only limited sintering of the metal nanoparticles is observed at high temperatures (700 °C). In addition, the as‐synthesized yolk@shell structures exhibit high and stable activity toward CO electrooxidation, thus demonstrating the applicability of our approach for the design of functional yolk@shell nanocatalysts.
Aryl λ3‐Iodane‐Mediated 6‐exo‐trig Cyclization to Synthesize Highly Substituted Chiral Morpholines
Authors: Kishore Vandavasi Jaya , Hu Wan‐Ping , Chandru Senadi Gopal , Chen Hui‐Ting , Chen Hsing‐Yin , Hsieh Kuang‐Chan , Wang Jeh‐Jeng
Published: September 2015

A mild and efficient transition metal‐free approach has been developed for the synthesis of highly substituted chiral morpholines from alkenols by amino acid‐derived iodine(III) reagents via a 6‐exo‐trig cyclization. The key features of this work include the formation of three chiral centers with a high diastereomeric ratio, broad functional group compatibility, and atom/time economic methodology.

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Intermolecular versus Intramolecular Palladium‐Catalyzed Direct Arylations between 1‐(2‐Bromobenzyl)imidazoles and Aryl Bromides
Authors: Xu Xiaowen , Zhao Liqin , Li Yiqun , Soulé Jean‐François , Doucet Henri
Published: September 2015

Herein, we report on the sequential palladium‐catalyzed intermolecular followed by intramolecular direct arylations of 1‐(2‐bromobenzyl)imidazoles. We found that, in the presence of 1 mol% palladium acetate and potassium acetate as base, the intermolecular reaction between 1‐(2‐bromobenzyl)imidazole derivatives and electron‐deficient aryl bromides proceeded faster than the intramolecular reaction, allowing us to prepare medium‐size polycyclic imidazoles after a second Pd‐catalyzed intramolecular arylation. These iterative direct arylations allowed the synthesis of fused nitrogen‐containing heterocycles with a 5‐ or 7‐membered‐ring in only two steps. Some reactions have also been performed as a one‐pot procedure using 2 mol% of palladium acetate in the presence of a larger amount of base (3 equiv.).

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Enantioselective α‐Alkylation of Benzylideneamino tert‐Butyl Malonates by Phase‐Transfer Catalysis
Authors: Park Cheonhyoung , Ha Min Woo , Kim Byungsoo , Hong Suckchang , Kim Doyoung , Park Yohan , Kim Mi‐hyun , Lee Jae Kyun , Lee Jeeyeon , Park Hyeung‐geun
Published: September 2015

A new enantioselective synthetic method for the synthesis of α,α‐dialkylmalonates with a quaternary carbon center was developed via α‐alkylation of prochiral malonates by phase‐transfer catalysis (PTC). Asymmetric α‐alkylation of benzylideneamino tert‐butyl α‐methylmalonates under phase‐transfer catalytic conditions in the presence of (S,S)‐3,4,5‐trifluorophenyl‐NAS bromide afforded the corresponding α,α‐dialkylmalonates in high yields (up to 97%) with excellent enantioselectivities (up to 98% ee). The products were then selectively hydrolyzed to chiral malonic monoacids under basic, acidic, or catalytic hydrogenation conditions.

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Platinum(IV)‐Catalyzed Synthesis of Unsymmetrical Polysubstituted Benzenes via Intramolecular Cycloaromatization Reaction
Authors: Zheng Shuyan , Zhang Jinghua , Shen Zhengwu
Published: September 2015

A one‐pot synthesis of polysubstituted benzene derivatives was achieved via a platinum(IV)‐catalyzed intramolecular cycloaromatization reaction. The reaction proceeds via a tandem skeletal rearrangment, dehydration and double bond isomerization, which proved to be very useful for the syntheses of a range of interesting polyalkyl‐substituted benzenes.

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Direct Synthesis of Hemiaminal Ethers via a Three‐Component Reaction of Aldehydes, Amines and Alcohols
Authors: Beltrán Álvaro , Álvarez Eleuterio , Díaz‐Requejo M. Mar , Pérez Pedro J.
Published: September 2015

The reaction of aldehydes, amines and alcohols usually leads to a series of equilibria from which isolation of one product is difficult to achieve. We have found that this three‐component reaction can be controlled and directed in an exclusive manner toward the formation of the hemiaminal ether. A series of 33 hemiaminal ethers has been obtained in high yields, from different aldehydes, amines and alcohols, under very mild conditions just with molecular sieves as promoter.

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Development and In Vitro Evaluation of High Molecular Weight Chitosan Based Polymeric Composites for Controlled Delivery of Valsartan
Authors: SOHAIL MUHAMMAD , AHMAD MAHMOOD , MINHAS MUHAMMAD USMAN , RASHID HAROON , KHALID IKRIMA
Published: September 2015

The purpose of present study was to develop chemically cross‐linked chitosan‐co‐poly(AMPS) hydrogel for pH‐responsive and controlled delivery of valsartan. Hydrogels were synthesized using the free radical polymerization technique. A polymer (high molecular weight chitosan) was chemically cross‐linked with monomer (2‐acrylamido‐2‐methylpropane sulfonic acid (AMPS)) in aqueous medium. NʹNʹ‐Methylenebisacrylamide was used as a cross‐linker. Sodium hydrogen sulfite and ammonium peroxodisulfate were used as initiators. Drug loading was performed with valsartan as a model drug. Characterization of hydrogels was performed by SEM, FTIR, and DSC. Hydrogels were evaluated for pH‐responsive behavior by the equilibrium swelling ratio and swelling dynamics at low and high pH. The developed cross‐linked network showed pH‐dependent drug release characteristics. Maximum swelling, drug loading, and release have been observed at pH 7.4. It is concluded that highly stable chitosan and AMPS‐based polymeric matrices are developed. These polymeric matrices have potential to be used as a carrier for controlled delivery of valsartan.
Severe congenital neutropenia with neurological impairment due to a homozygous VPS45 p.E238K mutation: A case report suggesting a genotype–phenotype correlation
Authors: Meerschaut Ilse , Bordon Victoria , Dhooge Catharina , Delbeke Patricia , Vanlander Arnaud V. , Simon Amos , Klein Christoph , Kooy R. Frank , Somech Raz , Callewaert Bert
Published: September 2015

VPS45 mutations cause severe congenital neutropenia (SCN). We report on a girl with SCN and neurological impairment harboring a homozygous p.E238K mutation in VPS45 (vacuolar sorting protein 45). She successfully underwent hematopoietic stem cell transplantation. Our findings delineate the phenotype and indicate a possible genotype–phenotype correlation for neurological involvement. © 2015 Wiley Periodicals, Inc.
Generation of Hydrogen from Zero‐Valent Iron and Water: Catalytic Transfer Hydrogenation of Olefins in Presence of Pd/C
Authors: Patil Rajendra D. , Sasson Yoel
Published: September 2015

A non‐hazordous and mild protocol was developed for an efficient reduction of alkenes to alkanes using “iron‐activated water” and catalytic Pd/C (2.5 mol %). Water functions as a hydrogen source without any external acid or base and in the absence of another solvent. The Pd/C catalyst was recovered and recycled. In the course of the reaction zero valent iron is oxidized to magnetite.
Photoredox‐Catalyzed Stereoselective Conversion of Alkynes into Tetrasubstituted Trifluoromethylated Alkenes
Authors: Tomita Ren , Koike Takashi , Akita Munetaka
Published: September 2015

A regio‐ and stereoselective synthesis of trifluoromethylated alkenes bearing four different substituents has been developed. Stereocontrolled sulfonyloxytrifluoromethylation of unsymmetric internal alkynes with an electrophilic CF3 reagent, namely the triflate salt of the Yagupol’skii–Umemoto reagent, in the presence of an Ir photoredox catalyst under visible‐light irradiation afforded trifluoromethylalkenyl triflates with well‐predictable stereochemistry resulting from anti addition of the trifluoromethyl and triflate groups. Subsequent palladium‐catalyzed cross‐couplings led to tetrasubstituted trifluoromethylated alkenes in a highly stereoselective manner. The present method is the first example of a facile one‐pot synthesis of tetrasubstituted trifluoromethylated alkenes from simple alkynes.
Comparison of dppf‐Supported Nickel Precatalysts for the Suzuki–Miyaura Reaction: The Observation and Activity of Nickel(I)
Authors: Guard Louise M. , Mohadjer Beromi Megan , Brudvig Gary W. , Hazari Nilay , Vinyard David J.
Published: September 2015

Ni‐based precatalysts for the Suzuki–Miyaura reaction have potential chemical and economic advantages compared to commonly used Pd systems. Here, we compare Ni precatalysts for the Suzuki–Miyaura reaction supported by the dppf ligand in 3 oxidation states, 0, I and II. Surprisingly, at 80 °C they give similar catalytic activity, with all systems generating significant amounts of NiI during the reaction. At room temperature a readily accessible bench‐stable NiII precatalyst is highly active and can couple synthetically important heterocyclic substrates. Our work conclusively establishes that NiI species are relevant in reactions typically proposed to involve exclusively Ni0 and NiII complexes.
Bioorthogonale enzymatische Aktivierung maskierter Verbindungen
Authors: Ritter Cornelia , Nett Nathalie , Acevedo‐Rocha Carlos G. , Lonsdale Richard , Kräling Katja , Dempwolff Felix , Hoebenreich Sabrina , Graumann Peter L. , Reetz Manfred T. , Meggers Eric
Published: September 2015

Wir berichten über die Verwendung evolvierter Varianten von Cytochrom‐P450‐Monooxygenasen als hochaktive und hochselektive Katalysatoren für die bioorthogonale Aktivierung Propargylether‐ und Benzylether‐maskierter Substrate, einschließlich der erfolgreichen Entschützung in lebenden E. coli. Docking‐Studien und Moleküldynamik‐Simulationen stützen die beobachtete Selektivität. Diese Studie veranschaulicht den möglichen Nutzen von bioorthogonalen Paaren aus Enzym und Schutzgruppe für Anwendungen in den Lebenswissenschaften.
Long‐Range Residual Dipolar Couplings: A Tool for Determining the Configuration of Small Molecules
Authors: Nath Nilamoni , d'Auvergne Edward J. , Griesinger Christian
Published: September 2015

Together with NOE and J coupling, one‐bond residual dipolar coupling (RDC), which reports on the three‐dimensional orientation of an internuclear vector in the molecular frame, plays an important role in the conformation and configuration analysis of small molecules in solution by NMR spectroscopy. When the molecule has few CH bonds, or too many bonds are in parallel, the available RDCs may not be sufficient to obtain the alignment tensor used for structure elucidation. Long‐range RDCs that connect nuclei over multiple bonds are normally not parallel to the single bonds and therefore complement one‐bond RDCs. Herein we present a method for extracting the long‐range RDC of a chosen proton or group of protons to all remotely connected carbon atoms, including non‐protonated carbon atoms. Alignment tensors fitted directly to the total long‐range couplings (T=J+D) enabled straightforward analysis of both the long‐range and one‐bond RDCs for strychnine.
Rational Control of Polyketide Extender Units by Structure‐Based Engineering of a Crotonyl‐CoA Carboxylase/Reductase in Antimycin Biosynthesis
Authors: Zhang Lihan , Mori Takahiro , Zheng Qingfei , Awakawa Takayoshi , Yan Yan , Liu Wen , Abe Ikuro
Published: September 2015

Bioengineering of natural product biosynthesis is a powerful approach to expand the structural diversity of bioactive molecules. However, in polyketide biosynthesis, the modification of polyketide extender units, which form the carbon skeletons, has remained challenging. Herein, we report the rational control of polyketide extender units by the structure‐based engineering of a crotonyl‐CoA carboxylase/reductase (CCR), in the biosynthesis of antimycin. Site‐directed mutagenesis of the CCR enzyme AntE, guided by the crystal structure solved at 1.5 Å resolution, expanded its substrate scope to afford indolylmethylmalonyl‐CoA by the V350G mutation. The mutant A182L selectively catalyzed carboxylation over the regular reduction. Furthermore, the combinatorial biosynthesis of heterocycle‐ and substituted arene‐bearing antimycins was achieved by an engineered Streptomyces strain bearing AntEV350G. These findings deepen our understanding of the molecular mechanisms of the CCRs, which will serve as versatile biocatalysts for the manipulation of building blocks, and set the stage for the rational design of polyketide biosynthesis.
Silver(I)‐Catalyzed N‐Trifluoroethylation of Anilines and O‐Trifluoroethylation of Amides with 2,2,2‐Trifluorodiazoethane
Authors: Luo Haiqing , Wu Guojiao , Zhang Yan , Wang Jianbo
Published: September 2015

A straightforward N‐trifluoroethylation of anilines has been developed based on silver‐catalyzed NH insertions with 2,2,2‐trifluorodiazoethane (CF3CHN2). Mechanistically, the reaction is proposed to involve migratory insertion of a silver carbene as the key step. In contrast, when amides are employed as the substrates under similar reaction conditions, O‐trifluoroethylation occurs to afford trifluoroethyl imidates.
Conformational Analysis, Thermal Rearrangement, and EI‐MS Fragmentation Mechanism of (1(10)E,4E,6S,7R)‐Germacradien‐6‐ol by 13C‐Labeling Experiments
Authors: Rabe Patrick , Barra Lena , Rinkel Jan , Riclea Ramona , Citron Christian A. , Klapschinski Tim A. , Janusko Aron , Dickschat Jeroen S.
Published: September 2015

An uncharacterized terpene cyclase from Streptomyces pratensis was identified as (+)‐(1(10)E,4E,6S,7R)‐germacradien‐6‐ol synthase. The enzyme product exists as two interconvertible conformers, resulting in complex NMR spectra. For the complete assignment of NMR data, all fifteen (13C1)FPP isotopomers (FPP=farnesyl diphosphate) and (13C15)FPP were synthesized and enzymatically converted. The products were analyzed using various NMR techniques, including 13C, 13C COSY experiments. The (13C)FPP isotopomers were also used to investigate the thermal rearrangement and EI fragmentation of the enzyme product.
Aminating modification of viscose fibers and their CO2 adsorption properties
Authors: Wu Qinghua , Chen Shuixia , Luo Shihe , Xu Teng
Published: September 2015

An adsorbent for CO2 capture was prepared by the grafting of acrylonitrile (AN) onto viscose fibers (VFs); this was followed by amination with triethylene tetramine (TETA). The effects of the reaction conditions, such as the concentrations of the monomer, initiator, and nitric acid, on the grafting degree and grafting efficiency were studied. The adsorption performance of the adsorbent for CO2 was evaluated by fixed‐bed adsorption. The highest dynamic adsorption capacity of the adsorbent for CO2 was 4.35 mmol/g when the amine content of the adsorbent VF–AN–TETA reached 13.21 mmol/g. Compared with the polypropylene (PP)‐fiber‐based adsorbent (PP–AN–TETA), VF–AN–TETA with hydroxyl groups on the fibers facilitated the diffusion of CO2 and water and led to a higher CO2 adsorption capacity than that of PP–AN–TETA. The VF–AN–TETA adsorbent also showed good regeneration performance: its CO2 adsorption capacity could still retain almost the same capacity as the fresh adsorbent after 10 adsorption–desorption cycles. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 132, 42840.
Induction of Canonical Wnt Signaling by the Alarmins S100A8/A9 in Murine Knee Joints: Implications for Osteoarthritis
Authors: van den Bosch Martijn H. , Blom Arjen B. , Schelbergen Rik F. P. , Vogl Thomas , Roth Johannes P. , Slöetjes Annet W. , van den Berg Wim B. , van der Kraan Peter M. , van Lent Peter L. E. M.
Published: September 2015

Objective

Both alarmins S100A8/A9 and canonical Wnt signaling have been found to play active roles in the development of experimental osteoarthritis (OA). However, what activates canonical Wnt signaling remains unknown. This study was undertaken to investigate whether S100A8 induces canonical Wnt signaling and whether S100 proteins exert their effects via activation of Wnt signaling.

Methods

Expression of the genes for S100A8/A9 and Wnt signaling pathway members was measured in an experimental OA model. Selected Wnt signaling pathway members were overexpressed, and levels of S100A8/A9 were measured. Activation of canonical Wnt signaling was determined after injection of S100A8 into naive joints and induction of collagenase‐induced OA in S100A9‐deficient mice. Expression of Wnt signaling pathway members was tested in macrophages and fibroblasts after S100A8 stimulation. Canonical Wnt signaling was inhibited in vivo to determine if the effects of S100A8 injections were dependent on Wnt signaling.

Results

The alarmins S100A8/A9 and members of the Wnt signaling pathway showed coinciding expression in synovial tissue in an experimental OA model. Synovial overexpression of selected Wnt signaling pathway members did not result in increased expression of S100 proteins. In contrast, intraarticular injection of S100A8 increased canonical Wnt signaling, whereas canonical Wnt signaling was decreased after induction of experimental OA in S100A9‐deficient mice. S100A8 stimulation of macrophages, but not fibroblasts, resulted in increased expression of canonical Wnt signaling members. Overexpression of Dkk‐1 to inhibit canonical Wnt signaling decreased the induction of matrix metalloproteinase 3, interleukin‐6, and macrophage inflammatory protein 1α after injection of S100A8.

Conclusion

Our findings indicate that the alarmin S100A8 induces canonical Wnt signaling in macrophages and murine knee joints. The effects of S100A8 are partially dependent on activation of canonical Wnt signaling.
Smoking and Its Association With Morbidity in Systemic Lupus Erythematosus Evaluated by the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index: Preliminary Data and Systematic Review
Authors: Montes Ricardo A. , Mocarzel Luiz O. , Lanzieri Pedro G. , Lopes Lais M. , Carvalho Amanda , Almeida Jorge R.
Published: September 2015

Objective

Due to the increased availability of effective treatments, patients with systemic lupus erythematosus (SLE) now have longer survival times, and factors involved in cumulative chronic damage in SLE need to be better understood. This study was undertaken to evaluate the relationship between smoking and cumulative chronic damage in SLE patients.

Methods

A cross‐sectional study of SLE patients was performed to investigate the possible association between smoking exposure (ever [previous or current, active or secondhand smokers] or never) and cumulative chronic damage as measured by the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI). A systematic review of the literature was conducted by cross‐searching Medline for the terms lupus and smoking.

Results

We enrolled 105 patients with SLE (96% female), with a mean ± SD age of 40.7 ± 11.4 years and a mean followup time of 8.98 years. Of the 105 patients, 74 had an SDI score of 1–10, and 31 had an SDI score of 0. The difference between smoking exposure and no smoking exposure was significant (P = 0.02 by chi‐square test in contingency table analysis), and SLE patients who were never exposed to smoking had 0.78 times the risk of progressing toward a cumulative damage status (SDI score of > 0) (95% confidence interval 0.16–0.98) throughout the followup period compared to those who were ever exposed. In the systematic review of the literature, we found only a small number of articles that addressed some aspects of the relationship between smoking exposure and cumulative damage in SLE patients.

Conclusion

Our findings indicate that smoking exposure is associated with cumulative chronic damage, as determined by the SDI score, in patients with SLE. Smoking exposure may have deleterious effects on lupus morbidity, and more detailed studies of this association are needed.
Water‐Soluble Fluorescent Probes for Selective Recognition of Lysine and Its Application in an Object Carry‐and‐Release System
Authors: Ma Hengchang , Qi Chunxuan , Cao Haiying , Zhang Zhongwei , Yang Zengming , Zhang Bing , Chen Chao , Lei Zi Qiang
Published: September 2015

A water‐soluble fluorescent probe PEG‐TPA‐5′ was synthesized, which shows an excellent selectivity to detect Lys in aqueous phase. An object carry‐and‐release system is established by applying PEG‐TPA‐5′ as carrier and Lys as chemical stimulating source.
Spectral analysis on origination of the bands at 437 nm and 475.5 nm of chlorophyll fluorescence excitation spectrum in Arabidopsis chloroplasts
Authors: Zeng Lizhang , Wang Yongqiang , Zhou Jun
Published: September 2015

Chlorophyll fluorescence has been often used as an intrinsic optical molecular probe to study photosynthesis. In this study, the origin of bands at 437 and 475.5 nm in the chlorophyll fluorescence excitation spectrum for emission at 685 nm in Arabidopsis chloroplasts was investigated using various optical analysis methods. The results revealed that this fluorescence excitation spectrum was related to the absorption characteristics of pigment molecules in PSII complexes. Moreover, the excitation band centred at 475.5 nm had a blue shift, but the excitation band at 437 nm changed relatively less due to induction of non‐photochemical quenching (NPQ). Furthermore, fluorescence emission spectra showed that this blue shift occurred when excitation energy transfer from both chlorophyll b (Chl b) and carotenoids (Cars) to chlorophyll a (Chl a) was blocked. These results demonstrate that the excitation band at 437 nm was mainly contributed by Chl a, while the excitation band at 475.5 nm was mainly contributed by Chl b and Cars. The chlorophyll fluorescence excitation spectrum, therefore, could serve as a useful tool to describe specific characteristics of light absorption and energy transfer between light‐harvesting pigments. Copyright © 2015 John Wiley & Sons, Ltd.
Effects of the Surface Densities of Glycoclusters on the Determination of Their IC50 and Kd Value Determination by Using a Microarray
Authors: Dupin Lucie , Zuttion Francesca , Géhin Thomas , Meyer Albert , Phaner‐Goutorbe Magali , Vasseur Jean‐Jacques , Souteyrand Eliane , Morvan François , Chevolot Yann
Published: September 2015

Pseudomonas aeruginosa (PA) is an opportunistic bacterium involved in 10–30 % of nosocomial diseases. It causes severe lung injury to cystic fibrosis patients, often leading to patient death. PA strains are multidrug resistant, thus making the design of new therapeutics a challenge for public health. One promising therapeutic option is to design glycoclusters that target the virulence factor of PA. LecA is a galactose‐specific lectin that might be involved in adhesion and biofilm formation by PA. The DNA‐directed immobilization (DDI) microarray is a powerful tool for screening and understanding of structure–activity relationships between glycoclusters and lectins. High‐throughput and multiplexed analysis of lectin–glycocluster interactions on a DDI microarray allows measurement of IC50 and dissociation constant (Kd) values with minute amounts of material. In order to study the robustness of the DDI microarray in determination of IC50 and Kd values, the impact of glycocluster surface density was investigated. The data obtained show that measured IC50 values were influenced by glycocluster surface density: as the density of glycoclusters increases, the measured IC50 values increase too. In contrast, the measured Kd values were not affected by glycocluster surface density, provided that the experimental conditions allow interaction between glycocluster and lectin at single‐molecule level (no surface cluster effect).
Effect of proper oral rehabilitation on general health of mandibulectomy patients
Authors: Mustafa Ammar A. , Raad Kais , Mustafa Nazih S.
Published: September 2015

Key Clinical Message

Here, we aimed to assess whether postoperative oral rehabilitation for mandibulectomy patients is necessary to improve patients’ general health in terms of health‐related quality of life.