bluuebunny/crossref_metadata_2025 huggingface dataset:
Enlisting Markets in the Conservation and Sustainable Use of Biodiversity in South Asia’s Sundarbans
Authors: Biller Dan , Sanchez-Triana Ernesto
Published: November 2013

The unique biodiversity of the Sundarbans is threatened by a number of factors, many of which are the direct or indirect result of market failures. Past governmental interventions aiming at protecting biodiversity have been ineffective, while other government efforts have directly or indirectly led to ecosystem degradation. In order to address these challenges, new governmental interventions are needed, particularly those that have the potential to mitigate market failures and address policy failures. This paper discusses how institutional and market failures, particularly the failure to capture the value of biodiversity as a 'public good', are the key drivers of biodiversity loss in the Sundarbans region of India. It argues that policy interventions to address these failures, as well as other measures that foster the development of markets that recognize the economic value of biodiversity, are a crucial tool for conserving and promoting the sustainable use of the Sundarbans' biodiversity. After describing the study area, a novel integrative development model, the potential for sustainable provision of private, public goods, and ecosystem services and the factors threatening them, the paper concludes with four policy suggestions that may assist in enabling biodiversity conservation and sustainable use in the Sundarbans.
Diagnosis of Biliary Atresia Can Not Be Excluded by Declining Trend of Serum Direct Bilirubin
Authors: Terui Keita , Higashimoto Yasuyuki , Saito Eriko , Saito Takeshi , Mitsuanga Tetsuya , Nakata Mitsuyuki , Iwai Jun , Yoshida Hideo
Published: November 2013

The aim of this paper is to investigate the clinical courses of patients with biliary atresia (BA) during neonatal period. We examined 19 patients with BA, who underwent blood tests including direct bilirubin (D-Bil) within 20 days of age, in 3 tertiary hospitals in Japan. The first blood sample was collected at 8.4±6.5 days of age. The acholic stool was observed within 2 weeks of age in 16 cases (84.2%). Decrease of T-Bil was observed in all the subjects, with a range of reduction of 6.5±3.3 mg/dL, from 10.4±7.5 to 29.8±9.1 days of age. Decrease of D-Bil was also observed in 17 out of 19 cases (89%), with a range of reduction of 1.1±1.0 mg/dL, from 15.5±8.0 to 24.9±9.6 days of age. A significant decrease of D-Bil was observed in 2 cases of biliary atresia splenic malformation syndrome. We therefore conclude that clinicians treating icteric infants should not exclude a diagnosis of BA even if the level of D-Bil has a declining tendency.
Feldspar minerals as efficient deposition ice nuclei
Authors: Yakobi-Hancock J. D. , Ladino L. A. , Abbatt J. P. D.
Published: November 2013

Abstract. Mineral dusts are well known to be efficient ice nuclei, where the source of this efficiency has typically been attributed to the presence of clay minerals such as illite and kaolinite. However, the ice nucleating abilities of the more minor mineralogical components have not been as extensively examined. As a result, the deposition ice nucleation abilities of 24 atmospherically relevant mineral samples have been studied, using a continuous flow diffusion chamber at −40.0 ± 0.3 °C and particles size-selected at 200 nm. By focussing on using the same experimental procedure for all experiments, a relative ranking of the ice nucleating abilities of the samples was achieved. In addition, the ice nucleation behaviour of the pure minerals is compared to that of complex mixtures, such as Arizona Test Dust (ATD) and Mojave Desert Dust (MDD), and to lead iodide, which has been previously proposed for cloud seeding. Lead iodide was the most efficient ice nucleus (IN), requiring a critical relative humidity with respect to ice (RHi) of 122.0 ± 2.0% to activate 0.1% of the particles. MDD (RHi) 126.3 ± 3.4%) and ATD (RHi 129.5 ± 5.1%) have lower but comparable activity. From a set of clay minerals (kaolinite, illite, montmorillonite), non-clay minerals (e.g. hematite, magnetite, calcite, cerussite, quartz), and feldspar minerals (orthoclase, plagioclase) present in the atmospheric dusts, it was found that the feldspar minerals (particularly orthoclase) and some clays (particularly kaolinite) were the most efficient ice nuclei. Orthoclase and plagioclase were found to have critical RHi values of 127.1 ± 6.3% and 136.2 ± 1.3%, respectively. The presence of feldspars (specifically orthoclase) may play a significant role in the IN behaviour of mineral dusts despite their lower percentage in composition relative to clay minerals.
On the detection of the solar signal in the tropical stratosphere
Authors: Chiodo G. , Marsh D. R. , Garcia-Herrera R. , Calvo N. , García J. A.
Published: November 2013

Abstract. We investigate the relative role of volcanic eruptions, El-Niño Southern-Oscillation (ENSO) and the Quasi-Biennal-Oscillation (QBO) in the quasi-decadal signal in the tropical stratosphere in temperature and ozone commonly attributed to the 11 yr solar cycle. For this purpose, we perform transient simulations with the Whole Atmosphere Community Climate Model forced from 1960 to 2004 with an 11 yr solar cycle in irradiance and different combinations of other forcings. An improved multiple regression technique is used to diagnose the 11 yr solar signal in the simulations. One set of simulations includes all observed forcings, and is thereby aimed at closely reproducing observations. Three idealized sets exclude ENSO variability, volcanic aerosol forcing, and QBO in tropical stratospheric winds, respectively. Differences in the derived solar response in the tropical stratosphere in the four sets quantify the impact of ENSO, volcanic events and the QBO in attributing quasi-decadal changes to the solar cycle in the model simulations. It is shown that most of the apparent solar-induced lower stratospheric temperature and ozone increase diagnosed in the simulations with all observed forcings is due to two major volcanic eruptions (i.e., El Chichón in 1982 and Mt. Pinatubo in 1991), that are concurrent with periods of high solar activity. While in the middle and upper tropical stratosphere, it is feasible to detect a robust solar signal, this is not the case in the tropical lower stratosphere, at least in a 45 yr record. The present results suggest that in the tropical lower stratosphere, the portion of decadal variability that can be unambigously linked to the solar cycle may be smaller than previously thought.
Jakub Charvát: Politika volebních reforem v ČR po roce 1989.
Authors: Cabada Ladislav
Published: November 2013

Knižní recenze
Trade‐offs between global warming and day length on the start of the carbon uptake period in seasonally cold ecosystems
Authors: Wohlfahrt Georg , Cremonese Edoardo , Hammerle Albin , Hörtnagl Lukas , Galvagno Marta , Gianelle Damiano , Marcolla Barbara , di Cella Umberto Morra
Published: November 2013

It is well established that warming leads to longer growing seasons in seasonally cold ecosystems. Whether this goes along with an increase in the net ecosystem carbon dioxide (CO2) uptake is much more controversial. We studied the effects of warming on the start of the carbon uptake period (CUP) of three mountain grasslands situated along an elevational gradient in the Alps. To this end, we used a simple empirical model of the net ecosystem CO2 exchange, calibrated, and forced with multiyear empirical data from each site. We show that reductions in the quantity and duration of daylight associated with earlier snowmelts were responsible for diminishing returns, in terms of carbon gain, from longer growing seasons caused by reductions in daytime photosynthetic uptake and increases in nighttime losses of CO2. This effect was less pronounced at high, compared to low, elevations, where the start of the CUP occurred closer to the summer solstice when changes in day length and incident radiation are minimal.
Perpendicular Orientation of Anisotropic Au‐Tipped CdS Nanorods at the Air/Water Interface
Authors: Kraus‐Ophir Shlomit , Ben‐Shahar Yuval , Banin Uri , Mandler Daniel
Published: November 2013

Anisotropic CdS nanorods tipped by Au nanoparticles on one edge (Au‐CdS‐NRs) are perpendicularly oriented at the air/water interface, whereby all the Au tips are located in the subphase, using the Langmuir–Blodgett technique. Since these nano‐objects reveal light‐induced charge separation at the semiconductor/metal interface, it is of high interest to control their organization. The orientation of these assemblies is studied in situ while compressing the Langmuir–Blodgett trough using the π‐A isotherm, Brewster angle microscopy, and horizontal touch voltammetry. All these analyses clearly confirm the induced organization of the amphiphilic Au‐CdS‐NRs by compression of the Langmuir layer. The compressed layers are successfully transferred by the Langmuir–Schaefer method onto transmission electron microscopy grids while maintaining the preferential orientation as analyzed by transmission, scanning and scanning trasmission electron microscopy, and X‐ray photoelectron spectroscopy. As far as can be determined, the Langmuir–Blodgett technique has not been used so far for perpendicularly orienting anisotropic nano‐objects. Moreover, these findings clearly demonstrate that anisotropic amphiphilic nano‐objects can be treated with some similarity to the traditional amphiphilic molecular building blocks.
Supercapacitor Electrodes Obtained by Directly Bonding 2D MoS2 on Reduced Graphene Oxide
Authors: da Silveira Firmiano Edney Geraldo , Rabelo Adriano C. , Dalmaschio Cleocir J. , Pinheiro Antonio N. , Pereira Ernesto C. , Schreiner Wido H. , Leite Edson Robeto
Published: November 2013

Layered molybdenum disulfide (MoS2) is deposited by microwave heating on a reduced graphene oxide (RGO). Three concentrations of MoS2 are loaded on RGO, and the structure and morphology are characterized. The first layers of MoS2 are detected as being directly bonded with the oxygen of the RGO by covalent chemical bonds (Mo‐O‐C). Electrochemical characterizations indicate that this electroactive material can be cycled reversibly between 0.25 and 0.8 V in 1 m HClO4 solution for hybrids with low concentrations of MoS2 layers (LCMoS2/RGO) and between 0.25 and 0.65 V for medium (MCMoS2/RGO) and high concentrations (HCMoS2/RGO) of MoS2 layers on graphene. The specific capacitance measured values at 10 mV s−1 are 128, 265, and 148 Fg−1 for the MoS2/RGO with low, medium, and high concentrations of MoS2, respectively, and the calculated energy density is 63 W h kg−1 for the LCMoS2/RGO hybrid. This supercapacitor electrode also exhibits superior cyclic stability with 92% of the specific capacitance retained after 1000 cycles.
Investigation of flow parameters and efficiency of mixture separation on a structured packing
Authors: Pavlenko Аleksandr , Zhukov Vladimir , Pecherkin Nikolay , Chekhovich Vladimir , Volodin Oleg , Shilkin Alexey , Grossmann Christoph
Published: November 2013

Results of experimental study of the effect of initial maldistribution of structured packing irrigation on efficiency of binary mixture separation are presented in this article. The studies were carried out in the experimental distillation column with the diameter of 0.9 m using the R114 and R21 freon mixture. Experiments were performed on the structured Mellapak 350.Y packing of stainless steel 316L, containing 19 layers with the total height of 4.016 m at the ratio of mole liquid and vapor flow rates L/V = 1 and 1.7, respectively, and the pressure in the upper part of the column ptop = 3 bars. Nonuniformity at the packing inlet was generated via the blocking of some holes in the liquid distributor. Here, we present some results on efficiency of mixture separation, pressure drop on the packing, distribution of local liquid flow rate under the packing over the cross‐section and on the column wall within the range of vapor loading factor (0.69 < Fv < 1.61 Pa0.5), as well as experimental data on distribution of local concentration of the low‐boiling component over the cross‐section and along the height of the structured packing. It is found out that significant maldistribution of mixture concentration and liquid flow rate over the cross‐section slightly changes along the height in the lower part of the column at a change in the degree of packing irrigation nonuniformity at the inlet. It is shown that efficiency of mixture separation depends considerably on the value of parameter L/V, vapor flow factor Fv, and size of the zone underirrigated by liquid at the inlet. In the studied range of liquid and vapor flow rates, the relative pressure drop on the packing does not depend on the ratio of liquid and vapor flow rates L/V and degree of irrigation maldistribution. © 2013 American Institute of Chemical Engineers AIChE J 60: 690–705, 2014
Application of online support vector regression for soft sensors
Authors: Kaneko Hiromasa , Funatsu Kimito
Published: November 2013

Soft sensors have been widely used in chemical plants to estimate process variables that are difficult to measure online. One of the crucial difficulties of soft sensors is that predictive accuracy drops due to changes in state of chemical plants. Characteristics of adaptive soft sensor models such as moving window models, just‐in‐time models and time difference models were previously discussed. The predictive accuracy of any traditional models decreases when sudden changes in processes occur. Therefore, a new soft sensor method based on online support vector regression (SVR) and the time variable was developed for constructing soft sensor models adaptive to rapid changes of relationships among process variables. A nonlinear SVR model with the time variable is updated with the most recent data. The proposed method was applied to simulation data and real industrial data, and achieved higher predictive accuracy than traditional ones even when time‐varying changes in process characteristics happen. © 2013 American Institute of Chemical Engineers AIChE J 60: 600–612, 2014
Lantabetulic Acid Derivatives Induce G1 Arrest and Apoptosis in Human Prostate Cancer Cells
Authors: Lin Kai‐Wei , Lin Zih‐You , Huang A‐Mei , Weng Jing‐Ru , Yen Ming‐Hong , Yang Shyh‐Chyun , Lin Chun‐Nan
Published: November 2013

Ten new lantabetulic acid (1) derivatives 2–11 were synthesized and their cytotoxicities against human prostate cancer cells were evaluated. PC3 cells treated with 10 μM 8 exhibited the most potent G1 phase arrest. In addition, 10 μM 8 markedly decreased the levels of cyclin E and cdk2 and caused an increase in the p21 and p27 levels, while 20 μM 8 mainly led to cell death through the apoptotic pathway, which correlated with an increase in reactive oxygen species levels, decreased expression levels of Bcl‐2 and caspase‐8, the induction of mitochondrial changes, and decreased levels of cytochrome c in mitochondria. The dual action of 8 could provide a new approach for the development of chemotherapeutic drugs.
Hydroxyalkylation with Cyclic Sulfates: Synthesis of Carbazole Derived CB2 Ligands with Increased Polarity
Authors: Lueg Corinna , Galla Fabian , Frehland Bastian , Schepmann Dirk , Daniliuc Constantin G. , Deuther‐Conrad Winnie , Brust Peter , Wünsch Bernhard
Published: November 2013

In order to increase the polarity of the potent CB2 ligand 1a, the homologous hydroxyalkyl carbazoles 2a–c were prepared and pharmacologically evaluated. An important step in the synthesis is the hydroxyalkylation of carbazole with cyclic sulfates providing the 2‐hydroxyethyl and 3‐hydroxypropyl derivatives 5a and 5b in a one‐step reaction. The final propionamides 2a–c were prepared using the recently reported coupling reagent COMU®. The X‐ray crystal structure of 2c displays an almost coplanar arrangement of the 3‐phenyl‐1,2,4‐oxadiazole biaryl system. The increased polarity of 2a is associated with an almost 100‐fold reduced CB2 affinity. The 3‐hydroxypropyl derivative 2b represents the best compromise between lipophilicity and CB2 affinity (Ki = 33 nM).
Novel Sulphamides and Sulphonamides Incorporating the Tetralin Scaffold as Carbonic Anhydrase and Acetylcholine Esterase Inhibitors
Authors: Akıncıoğlu Akın , Topal Meryem , Gülçin İlhami , Göksu Süleyman
Published: November 2013

Reactions of amino, aminomethyl tetralins and benzyl alcohol with chlorosulphonyl isocyanate (CSI) afforded sulphamoyl carbamates. The sulphamoyl carbamates were converted to sulphamides by palladium‐catalysed hydrogenolysis. Sulphonamides were synthesized from the reactions of amines with MeSO2Cl. Inhibition of human (h) carbonic anhydrase (CA) isoenzymes (hCA I, hCA II) and acetylcholine esterase (AChE) was investigated with the synthesized compounds. hCA I and hCA II were inhibited in the low micromolar or sub‐micromolar range. The Ki values were in the range of 0.91–9.56 µM against hCA I and of 3.70–27.88 µM against hCA II. Sulphamides 11–13 and sulphonamides 14–16 had moderate inhibition capacity toward AChE. These findings suggest the novel sulphamides 11–13 and sulphonamides 14–16 as AChE and CA isoenzyme inhibitory agents.
Assessment of Haloacetic Acids in Drinking Water in Bizerte, Tunisia
Authors: Hammami Bechir , Ben Hessin Sihem , Bahri Mohamed , Driss Mohamed Ridha
Published: November 2013

An investigation into the occurrence of haloacetic acids (HAAs) was conducted during a period of winter and summer seasons of the years 2008–2009 on the drinking water of Bizerte with variable conditions of water quality, pH, water temperature, total organic carbon, and bromide concentrations. The concentrations of HAAs were determined by a fast headspace solid‐phase microextraction GC method, which consists of liquid–liquid extraction, evaporation to dryness of extraction solvent then derivatization of the HAAs to their methyl haloacetates with sulfuric acid and methanol, followed by headspace solid‐phase microextraction with GC and electron capture detection. The results of the analyses show the presence of HAAs in all chlorinated water samples. The most prevalent HAAs were trichloroacetic acid (TCAA), dichloroacetic acid (DCAA), and monochloroacetic acid (MCAA) due to the low concentrations of bromide in the water treatment plant, while other HAAs were detected at low concentrations. The annual means concentrations of TCAA, DCAA and, MCAA varied from 3.9 to 26.25 µg L−1, from 2.76 to 23.19 µg L−1, and from 6.65 to 34.07 µg L−1, respectively. Seasonal variations in HAAs were mainly linked with changes in water temperature and variations of organic precursors, with HAA occurrence at its highest in summer. In all samples the concentrations of HAAs were lower than the maximum level set by the World Health Organization except for MCAA at the network extremity. Finally, a statistically significant (p < 0.05) regression analysis was used to examine the correlation of HAA5 with respect to some water quality parameters. Strong correlations between (total organic carbon, water temperature and chlorine dose) with HAA5 were observed.
Differential impairments underlying decision making in anorexia nervosa and bulimia nervosa: A cognitive modeling analysis
Authors: Chan Trista Wai Sze , Ahn Woo‐Young , Bates John E. , Busemeyer Jerome R. , Guillaume Sebastien , Redgrave Graham W. , Danner Unna N. , Courtet Philippe
Published: November 2013

Objective

This study examined the underlying processes of decision‐making impairments in individuals with anorexia nervosa (AN) and bulimia nervosa (BN). We deconstructed their performance on the widely used decision task, the Iowa Gambling Task (IGT) into cognitive, motivational, and response processes using cognitive modeling analysis. We hypothesized that IGT performance would be characterized by impaired memory functions and heightened punishment sensitivity in AN, and by elevated sensitivity to reward as opposed to punishment in BN.

Method

We analyzed trial‐by‐trial data of IGT obtained from 224 individuals: 94 individuals with AN, 63 with BN, and 67 healthy comparison individuals (HC). The prospect valence learning model was used to assess cognitive, motivational, and response processes underlying IGT performance.

Results

Individuals with AN showed marginally impaired IGT performance compared to HC. Their performance was characterized by impairments in memory functions. Individuals with BN showed significantly impaired IGT performance compared to HC. They showed greater relative sensitivity to gains as opposed to losses than HC. Memory functions in AN were positively correlated with body mass index.

Discussion

This study identified differential impairments underlying IGT performance in AN and BN. Findings suggest that impaired decision making in AN might involve impaired memory functions. Impaired decision making in BN might involve altered reward and punishment sensitivity. © 2013 Wiley Periodicals, Inc. (Int J Eat Disord 2014; 47:157–167)
Influence of carbon and nitrogen concentration on itaconic acid production by the smut fungus Ustilago maydis
Authors: Maassen Nicole , Panakova Monika , Wierckx Nick , Geiser Elena , Zimmermann Martin , Bölker Michael , Klinner Ulrich , Blank Lars Mathias
Published: November 2013

Itaconic acid is a valuable platform compound for the production of bio‐based polymers, chemicals, and fuels. Ustilago maydis is a promising host for the production of itaconic acid from biomass‐derived substrates due to its unicellular growth pattern and its potential to utilize biomass‐derived sugar monomers and polymers. The potential of U. maydis for industrial itaconate production was assessed in pH‐controlled batch fermentations with varying medium compositions. Using 200 g/L glucose and 75 mM ammonium, 44.5 g/L of itaconate was produced at a maximum rate of 0.74 g L−1 h−1. By decreasing the substrate concentrations to 50 g/L glucose and 30 mM ammonium, a yield of 0.34 g/g (47 mol%) could be achieved. Itaconate production from xylose was also feasible. These results indicate that high itaconic acid titers can be achieved with U. maydis. However, further optimization of the biocatalyst itself through metabolic engineering is still needed in order to achieve an economically feasible process, which can be used to advance the development of a bio‐based economy.
Effects of water recycling in hydrothermal carbonization of loblolly pine
Authors: Uddin M. Helal , Reza M. Toufiq , Lynam Joan G. , Coronella Charles J.
Published: November 2013

Hydrothermal carbonization (HTC) is a process to densify, homogenize, and stabilize diverse biomass feedstocks. The water requirements of HTC need to be assessed to determine commercial feasibility. This current research work focuses on the effects on HTC of using recycled process water for multiple process cycles. Loblolly pine was treated in hot, compressed water at 200, 230, and 260°C for 5 min with a 5:1 water:biomass mass ratio. Liquid product was separated and recycled for reuse in HTC, nine cycles at 200 and 230°C and five cycles at 260°C. The solid products (biocarbon) were characterized by their mass yields, higher heating values (HHVs), and equilibrium moisture content (EMC), whereas in the liquid samples, total organic carbon (TOC) content and pH were determined. With successive recycling, biocarbon mass yield increases by 5–10% above the yield recorded for the initial cycle at each temperature investigated, whereas biocarbon HHV is essentially unchanged. The aqueous TOC is increasingly concentrated with the number of cycles and reaches an equilibrium. The EMC results suggest that the effects of recycling process water on hydrophobicity of the biocarbon are negligible. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 1309–1315, 2014
Stochastic Skew in the Interest Rate Cap Market
Authors: Leung Kwai S. , Ng Hon Y. , Wong Hoi Y.
Published: November 2013

The term structure of interest rates cannot be used to fully explain and hedge the prices of interest rate derivatives. Unspanned stochastic volatility improves the accuracy of interest rate derivatives valuation but is still inadequate to capture the variation of skews in the implied volatility surface. In this study, we document the stochastic variation of implied volatility skews in the interest rate cap market. To develop a term structure model that is consistent with the empirical phenomena, we incorporate the Wishart process into the standard LIBOR market model, namely, the LIBOR N‐dimensional Wishart (“LNW” for short) market model and derive a closed‐form, accurate, efficient caplet pricing formula. The capacity of the LNW model to capture stochastic skews is examined and compared with that of LIBOR multi‐Heston (“LMH” for short) market model with two and three stochastic volatilities. We find that the LNW model outperforms its LMH counterparts in terms of both in‐sample and out‐of‐sample pricing errors. © 2013 Wiley Periodicals, Inc. Jrl Fut Mark 34:1146–1169, 2014
A new generation of poly(lactide/ε‐caprolactone) polymeric biomaterials for application in the medical field
Authors: Fernández J. , Larrañaga A. , Etxeberria A. , Wang W. , Sarasua J. R.
Published: November 2013

Thermoplastic biodegradable polymers displaying an elastomeric behavior are greatly valued for the regeneration of soft tissues and for various medical devices. In this work, terpolymers composed of ε‐caprolactone (CL), d‐lactide (d‐LA), and l‐lactide (l‐LA) were synthesized. These poly(lactide‐ε‐caprolactone) (PLCLs) presented an elevated randomness character (R∼1), glass transition temperatures (Tg) higher than 20°C and adjusted l‐LA content. In this way, the l‐LA average sequence length (lL‐LA) was reduced to below 3.62 and showed little or no crystallization capability during in vitro degradation. As a result, the obtained materials underwent homogenous degradation exhibiting KMw ranging from 0.030 to 0.066 d−1 and without generation of crystalline remnants in advanced stages of degradation. Mechanical performance was maintained over a period of 21 days for a rac‐lactide‐ε‐caprolactone copolymer composed of ∼85% d,l‐LA and ∼15% CL and also for a terpolymer composed of ∼72% l‐LA, ∼12% d‐LA and ∼16% CL. Terpolymers having l‐LA content from ∼60 to 70% and CL content from ∼10 to 27% were also studied. In view of the results, those materials having CL and d‐LA units disrupting the microstructural arrangement of the l‐LA crystallizable chains, an l‐LA content <72% and a random distribution of sequences, may display proper and tunable mechanical behavior and degradation performance for a large number of medical applications. Those with a CL content from 15 to 30% will fulfill the demand of elastomeric materials of Tg higher than 20°C whereas those with a CL content from 5 to 15% might be applied as ductile stiff materials. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3573–3584, 2014.
Fumed Silica Nanoparticle Mediated Biomimicry for Optimal Cell–Material Interactions for Artificial Organ Development
Authors: de Mel Achala , Ramesh Bala , Scurr David J. , Alexander Morgan R. , Hamilton George , Birchall Martin , Seifalian Alexander M.
Published: November 2013

Replacement of irreversibly damaged organs due to chronic disease, with suitable tissue engineered implants is now a familiar area of interest to clinicians and multidisciplinary scientists. Ideal tissue engineering approaches require scaffolds to be tailor made to mimic physiological environments of interest with specific surface topographical and biological properties for optimal cell‐material interactions. This study demonstrates a single‐step procedure for inducing biomimcry in a novel nanocomposite base material scaffold, to re‐create the extracellular matrix, which is required for stem cell integration and differentiation to mature cells. Fumed silica nanoparticle mediated procedure of scaffold functionalization, can be potentially adapted with multiple bioactive molecules to induce cellular biomimicry, in the development human organs. The proposed nanocomposite materials already in patients for number of implants, including world first synthetic trachea, tear ducts and vascular bypass graft.
Conversion of major soy isoflavone glucosides and aglycones in in vitro intestinal models
Authors: Islam Mohammed A. , Punt Ans , Spenkelink Bert , Murk Albertinka J. , Rolaf van Leeuwen F. X. , Rietjens Ivonne M. C. M.
Published: November 2013

Scope

This study compares conversion of three major soy isoflavone glucosides and their aglycones in a series of in vitro intestinal models.

Methods and results

In an in vitro human digestion model isoflavone glucosides were not deconjugated, whereas studies in a Caco‐2 transwell model confirmed that deconjugation is essential to facilitate transport across the intestinal barrier. Deconjugation was shown upon incubation of the isoflavone glucosides with rat as well as human intestinal S9. In incubations with rat intestinal S9 lactase phlorizin hydrolase, glucocerebrosidase, and cytosolic broad‐specific β‐glucosidase all contribute significantly to deconjugation, whereas in incubations with human intestinal S9 deconjugation appeared to occur mainly through the activity of broad‐specific β‐glucosidase. Species differences in glucuronidation and sulfation were limited and generally within an order of magnitude with 7‐O‐glucuronides being the major metabolites for all three isoflavone aglycones and the glucuronidation during first pass metabolism being more efficient in rats than in humans. Comparison of the catalytic efficiencies reveals that deconjugation is less efficient than conjugation confirming that aglycones are unlikely to enter the systemic circulation.

Conclusion

Altogether, the data point at possible differences in the characteristics for intestinal conversion of the major soy isoflavones between rat and human, especially with respect to their deconjugation.
Synthesis of orthogonally addressable block copolymers via reversible addition fragmentation chain transfer polymerization and subsequent chemoselective postmodification
Authors: Mardyukov Artur , Tesch Matthias , Studer Armido
Published: November 2013

This article describes the synthesis of bifunctional block copolymers (BCPs) of type 4 bearing orthogonally reactive backbone substituents such as 1,1,1,3,3,3‐hexafluoroisopropoxycarbonyl groups as active esters and α‐hydroxyalkylphenylketones (2‐hydroxy‐2‐methyl‐1‐phenylpropan‐1‐one) as additional photoactive moieties via reversible addition fragmentation chain transfer (RAFT) polymerization. As monomers 1,1,1,3,3,3‐hexafluoroisopropyl acrylate (HFIPA) and 2‐hydroxy‐2‐methyl‐1‐(4‐vinyl)phenylpropan‐1‐one (HAK) are used. Controlled radical polymerization provides BCPs p(HFIPA)‐b‐p(HAK) with molecular weights (Mn) ranging from 15,000 to 37,000 g mol−1 and low molecular weight distributions (PDI = 1.2–1.4). The incorporated HFIPA and HAK moieties are used for sequential chemoselective postmodification of 4. The photoactive block of 4 can be functionalized through a nitroxide photoclick trapping reaction in the presence of functionalized nitroxides and the active ester moieties of the p(HFIPA)‐block are readily thermally amidated using various amines. Chemically modified polymers are characterized by NMR, FTIR, and GPC methods which reveal a high degree of postfunctionalization, typically >95% for both orthogonal processes. The chemically modified polymers feature a narrow molecular weight distribution. The process is successfully applied to the synthesis of a small polymer library and also to the preparation of homo and block polynitroxides using 4‐amino‐TEMPO as amine component in the transamidation reaction. The polynitroxides obtained are characterized by cyclic voltammetry, FTIR, and UV–vis spectroscopy. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 52, 258–266
Synthesis and properties of cross‐linkable high molecular weight fluorinated copolyimides
Authors: Yao Hongyan , Zhang Yunhe , Liu Yu , You Kaiyuan , Liu Shanyou , Liu Baijun , Guan Shaowei
Published: November 2013

A series of novel high molecular weight fluorinated co‐polyimides (Co‐PIs) containing styryl side chain based on 1,3‐bis(2‐trifluoromethyl‐4‐aminophenoxy)‐5‐(2,3,4,5‐tetrafluorophenoxy)benzene (6FTFPB) were successfully synthesized. The weight‐average molecular weights (Mws) and polydispersities of the co‐polyimides were in the range 8.93–10.81 × 104 and 1.33–1.82, respectively. The co‐polyimide film showed excellent solubility in organic solvents, high tensile properties (tensile strength exceeded 91 MPa), excellent optical transparency (cutoff wavelength at 332–339 nm and light transparencies above 89% at a wavelength of 550 nm), and high thermal stability (5% thermal weight‐loss temperature up to 510 °C). The casting and spinning films could be cross‐linked by thermal curing. The cured films show better combination property (including excellent resistance to solvents) than that of co‐polyimides. For instance, the glass transition temperature of Co‐PI‐1 (the molar weight ratio of 6FTFPB was 30%) increased from 217 to 271 °C, the tensile strength enhanced from 94 to 96 MPa, the 5% thermal weight‐loss temperature improved from 514 to 525 °C. Moreover, after cured, Co‐PI‐1 film also has a coefficient of thermal expansion (CTE) value of 60.3 ppm °C−1, low root mean square surface roughness (Rq) at 4.130 nm and low dielectric constant of 2.60. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 349–359
Facile synthesis of heat‐resistant and photoluminescent poly(N‐aryleneindole ether)s via catalyst‐free CN/CO coupling reaction
Authors: Chang Guanjun , Yang Li , Yang Junxiao , Huang Yawen , Zhang Lin , Lin Runxiong
Published: November 2013

We present here a novel programmable polymerization route for the synthesis of new indole‐based polymers via a catalyst‐free nucleophilic substitution reaction. The polycondensation of 4‐hydroxyindole with different activated difluoro monomers undergoes in N‐methylpyrrolidinone, affording soluble poly(N‐aryleneindole ether)s (PEINs) with high molecular weights (Mw up to 486,000) in high yields (up to 96%). The structures of the polymers are characterized by means of FT‐IR, 1H NMR spectroscopy and elemental analysis, the results show good agreement with the proposed structures. The resulting polymers are processable and enjoy high glass transition temperatures (Tgs > 180 °C) and thermal stability (Tds > 420 °C). Thin films of PEINs show great mechanical behaviors with high tensile strength up to 104 Mpa, and good optical transparency. In addition, due to the indole moieties in the main chains, all these PEINs are endowed with significantly strong photonic luminescence in chloroform and display highly solvent‐dependent emission bands. Especially, the polymer PEIN‐3 carrying sulfonyl units, shows outstanding blue‐light emission with high quantum yields (45.2%, determined against quinine sulfate). The results obtained by cyclic voltammetry suggest that PEINs possess good electroactivity. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 313–320
Experimental and theoretical study of charge‐transfer complex hybrid polyimide membranes
Authors: Nishihara Masamichi , Christiani Liana , Staykov Aleksandar , Sasaki Kazunari
Published: November 2013

The nanostructure of sulfonated polyimide (SPI)/dihydroxynaphthalene (DHN) derivative charge‐transfer (CT) complex hybrid films, which are noble alternative polymer electrolyte membranes (PEMs), is determined by a combined visible spectroscopy/quantum mechanical approach. From the visible spectra of SPI/2,6‐dihydroxynaphthalene (2,6‐DHN) and 1,5‐dihydroxynaphthalene (1,5‐DHN) CT complex hybrid films, it is confirmed that these films have different maximum wavelength, although difference of the molecular structure is small. From the calculation based on the experimental result, SPI and DHNs form multiple interactions consisting of not only CT interaction, but also hydrogen bonding in multilayered structures. CT interaction between SPI and DHN defines the DHN position in the SPI matrix, with DHN sitting in the cavity formed between SPIs. The molecular structure of the CT films derived from the multiple and complex interactions can recognize small differences in the structural isomers and bring changes of the optical property. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 293–298
Controlled Synthesis of Kinked Ultrathin ZnS Nanorods/Nanowires Triggered by Chloride Ions: A Case Study
Authors: Zhuang Tao‐Tao , Yu Pan , Fan Feng‐Jia , Wu Liang , Liu Xiao‐Jing , Yu Shu‐Hong
Published: November 2013

Colloidal synthesis of kinked ultrathin ZnS nanorods/nanowires with mixed phases using tiny Ag2S nanocrystals as catalysts is reported. It is found that chloride ions can induce the controlled morphology transition from straight to kinking. The synthetic parameters modulating the growth of kinked ZnS nanorods/nanowires are systematically investigated. Chloride ions introduced in the reaction can generate more proportion of wurtzite phase by slowing the nucleation and growth rates during the growth of one‐dimensional (1D) ZnS nanorods/nanowires. The formation of kinked morphology is responsible for the increased domains of mixed stacking and twinning in single 1D nanostructures. The present recipe on controlled synthesis of 1D kinked nanorods/nanowires provides a model of crystal growth control, and these unique 1D nanostructures may also offer new opportunities to fabricate nanodevices with special functions.
Model improvements for evaluating the effect of tower tilting on the aerodynamics of a vertical axis wind turbine
Authors: Wang K. , Hansen M. O. L. , Moan T.
Published: November 2013

If a vertical axis wind turbine is mounted offshore on a semi‐submersible, the pitch motion of the platform will dominate the static pitch and dynamic motion of the platform and wind turbine such that the effect of tower tilting on the aerodynamics of the vertical axis wind turbine should be investigated to more accurately predict the aerodynamic loads. This paper proposes certain modifications to the double multiple‐streamtube (DMS) model to include the component of wind speed parallel to the rotating shaft. The model is validated against experimental data collected on an H‐Darrieus wind turbine in skewed flow conditions. Three different dynamic stall models are also integrated into the DMS model: Gormont's model with the adaptation of Strickland, Gormont's model with the modification of Berg and the Beddoes–Leishman dynamic stall model. Both the small Sandia 17 m wind turbine and the large DeepWind 5 MW are modelled. According to the experimental data, the DMS model with the inclusion of the dynamic stall model is also well validated. On the basis of the assumption that the velocity component parallel to the rotor shaft is small in the downstream part of the rotor, the effect of tower tilting is quantified with respect to power, rotor torque, thrust force and the normal force and tangential force coefficients on the blades. Additionally, applications of Glauert momentum theory and pure axial momentum theory are compared to evaluate the effect of the velocity component parallel to the rotor shaft on the accuracy of the model. Copyright © 2013 John Wiley & Sons, Ltd.
Strain-specific proteogenomics accelerates the discovery of natural products via their biosynthetic pathways
Authors: Albright Jessica C , Goering Anthony W , Doroghazi James R , Metcalf William W , Kelleher Neil L
Published: November 2013

The use of proteomics for direct detection of expressed pathways producing natural products has yielded many new compounds, even when used in a screening mode without a bacterial genome sequence available. Here we quantify the advantages of having draft DNA-sequence available for strain-specific proteomics using the latest in ultrahigh-resolution mass spectrometry for both proteins and the small molecules they generate. Using the draft sequence of Streptomyces lilacinus NRRL B-1968, we show a >tenfold increase in the number of peptide identifications vs. using publicly available databases. Detected in this strain were six expressed gene clusters with varying homology to those known. To date, we have identified three of these clusters as encoding for the production of griseobactin (known), rakicidin D (an orphan NRPS/PKS hybrid cluster), and a putative thr and DHB-containing siderophore produced by a new non-ribosomal peptide sythetase gene cluster. The remaining three clusters show lower homology to those known, and likely encode enzymes for production of novel compounds. Using an interpreted strain-specific DNA sequence enables deep proteomics for the detection of multiple pathways and their encoded natural products in a single cultured bacterium.
Local effects of gravity on foams
Authors: Davis Michael J. , Stewart Peter S. , Davis Stephen H.
Published: November 2013

The stability of a two-dimensional surfactant-free (gas–liquid) foam in a gravitational field is considered. The foam is assumed to have low liquid fraction, so the gas phase can be divided into approximately polygonal bubbles separated by thin liquid films. These free films drain toward accumulations of liquid at the bubble vertices, the Plateau borders, and eventually rupture due to van der Waals intermolecular attractions; this drives foam coarsening through the coalescence of neighbouring bubbles. In particular, we demonstrate how gravitational effects strongly modify the shape of the Plateau border interfaces and enhance the drainage flow in the liquid films, driving non-uniform thinning with exponential decay of the minimum film thickness, significantly faster than the power-law thinning predicted when gravitational effects are negligible.
High-speed laminar flow past a fin–body junction
Authors: Tutty O. R. , Roberts G. T. , Schuricht P. H.
Published: November 2013

Interference heating effects generated by a blunt fin-type protuberance on a flat plate exposed to a hypersonic flow have been investigated experimentally and numerically. Experiments and simulations were carried out at a free-stream Mach number of 6.7 under laminar flow conditions. The surface heating on the plate was measured experimentally using liquid-crystal thermography, which provided quantitative data with high spatial resolution. Complementary surface oil flow and schlieren experiments were also carried out to gain a better understanding of the interference flow field. The effects of fin leading-edge diameter on the heating distribution on the flat plate surface were explored. The results of the experiments and simulations agree well and reveal a highly complex interaction region which extends over seven diameters upstream of the fin. Within the interaction region surrounding the fin, heating enhancements up to ten times the undisturbed flat plate value were estimated from the experimental data. However, the liquid crystals have a limited range, and the numerical simulations indicated localized peak heating many times this value both on the plate and the fin itself.
The Boussinesq approximation in rapidly rotating flows
Authors: Lopez Jose M. , Marques Francisco , Avila Marc
Published: November 2013

In commonly used formulations of the Boussinesq approximation centrifugal buoyancy effects related to differential rotation, as well as strong vortices in the flow, are neglected. However, these may play an important role in rapidly rotating flows, such as in astrophysical and geophysical applications, and also in turbulent convection. Here we provide a straightforward approach resulting in a Boussinesq-type approximation that consistently accounts for centrifugal effects. Its application to the accretion-disc problem is discussed. We numerically compare the new approach to the typical one in fluid flows confined between two differentially heated and rotating cylinders. The results justify the need of using the proposed approximation in rapidly rotating flows.
THE ASEAN HUMAN RIGHTS DECLARATION AND THE IMPLICATIONS OF RECENT SOUTHEAST ASIAN INITIATIVES IN HUMAN RIGHTS INSTITUTION-BUILDING AND STANDARD-SETTING
Authors: Doyle Nicholas
Published: November 2013

On 18 November 2012 the ‘Association of Southeast Asian Nations’ (ASEAN) adopted the ASEAN Human Rights Declaration (AHRD). ASEAN has existed since 1967 and as a result allows Southeast Asia to be identified as a ‘region’ comparable with other regions such as Africa, the Americas and Europe which have been seen as such in human rights terms for over 40 years. However, until recently Southeast Asia has not been involved in a process of regional human rights institutionalization which in other regions has been an important means of implementing international human rights treaty commitments adopted by their member-States in global forums. Furthermore, the ten States of ASEAN as a group are parties to relatively few of the principal international human rights standard-setting and monitoring regimes. Hence vesting ASEAN with a human rights mandate would seem to present an opportunity to enhance the range of human rights commitments to which ASEAN States are subject. However, after reviewing the ‘ASEAN human rights mechanism’ it is concluded that much recent ASEAN activity amounts either to political rhetoric or has potential to fragment the human rights norms recognized by those ASEAN States which are committed to international human rights treaties. For the ASEAN States which are relatively uncommitted to international human rights treaty regimes, participating in the ASEAN mechanism may reduce pressure to recognize international norms.
Myogenic bladder defects in mouse models of human oculodentodigital dysplasia
Authors: Huang Tao , Shao Qing , Barr Kevin , Simek Jamie , Fishman Glenn I. , Laird Dale W.
Published: November 2013

To date, over 65 mutations in the gene encoding Cx43 (connexin43) have been linked to the autosomal-dominant disease ODDD (oculodentodigital dysplasia). A subset of these patients experience bladder incontinence which could be due to underlying neurogenic deterioration or aberrant myogenic regulation. BSMCs (bladder smooth muscle cells) from wild-type and two Cx43 mutant lines (Cx43G60S and Cx43I130T) that mimic ODDD exhibit a significant reduction in total Cx43. Dye transfer studies revealed that the G60S mutant was a potent dominant-negative inhibitor of co-expressed Cx43, a property not equally shared by the I130T mutant. BSMCs from both mutant mouse strains were defective in their ability to contract, which is indicative of phenotype changes due to harbouring the Cx43 mutants. Upon stretching, Cx43 levels were significantly elevated in controls and mutants containing BSMCs, but the non-muscle myosin heavy chain A levels were only reduced in cells from control mice. Although the Cx43G60S mutant mice showed no difference in voided urine volume or frequency, the Cx43I130T mice voided less frequently. Thus, similar to the diversity of morbidities seen in ODDD patients, genetically modified mice also display mutation-specific changes in bladder function. Furthermore, although mutant mice have compromised smooth muscle contraction and response to stretch, overriding bladder defects in Cx43I130T mice are likely to be complemented by neurogenic changes.
An Enantiomerically Pure Pyridine NC-Palladacycle Derived from [2.2]Paracyclophane
Authors: Glover Jean E. , Plieger Paul G. , Rowlands Gareth J.
Published: November 2013

An enantiomerically pure planar chiral pyridine-based palladacycle was prepared from [2.2]paracyclophane in just four steps. The palladacycle shows potential in catalysis, mediating the Suzuki coupling of an aryl chloride. It also permits the ortho bromination of [2.2]paracyclophane, a reaction that can be hard to achieve selectively.