bluuebunny/crossref_metadata_2025 huggingface dataset:
Graphene Oxides Prepared by Hummers’, Hofmann’s, and Staudenmaier’s Methods: Dramatic Influences on Heavy‐Metal‐Ion Adsorption
Authors: Moo James Guo Sheng , Khezri Bahareh , Webster Richard D. , Pumera Martin
Published: July 2014

Graphene oxide (GO), an up‐and‐coming material rich in oxygenated groups, shows much promise in pollution management. GO is synthesised using several synthetic routes, and the adsorption behaviour of GO is investigated to establish its ability to remove the heavy‐metal pollutants of lead and cadmium ions. The GO is synthesised by Hummers’ (HU), Hofmann’s (HO) and Staudenmaier’s (ST) methodologies. Characterisation of GO is performed before and after adsorption experiments to investigate the structure–function relationship by using Fourier‐transform infrared spectroscopy and X‐ray photoelectron spectroscopy. Scanning electron microscopy coupled with elemental detection spectroscopy is used to investigate morphological changes and heavy‐metal content in the adsorbed GO. The filtrate, collected after adsorption, is analysed by inductively coupled plasma mass spectrometry, through which the efficiency and adsorption capacity of each GO for heavy‐metal‐ion removal is obtained. Spectroscopic analysis and characterisation reveal that the three types of GO have different compositions of oxygenated carbon functionalities. The trend in the affinity towards both PbII and CdII is HU GO>HO GO>ST GO. A direct correlation between the number of carboxyl groups present and the amount of heavy‐metal ions adsorbed is established. The highest efficiency and highest adsorption capacity of heavy‐metal ions is achieved with HU, in which the relative abundance of carboxyl groups is highest. The embedded systematic study reveals that carboxyl groups are the principal functionality responsible for heavy‐metal‐ion removal in GO. The choice of synthesis methodology for GO has a profound influence on heavy‐metal‐ion adsorption. A further enrichment of the carboxyl groups in GO will serve to enhance the role of GO as an adsorbent for environmental clean‐up.
Water OH Bond Activation by Gas‐Phase Plutonium Atoms: Reaction Mechanisms and Ab Initio Molecular Dynamics Study
Authors: Li Peng , Niu Wenxia , Gao Tao , Wang Hongyan
Published: July 2014

A thorough description of the reaction mechanisms, taking into account different possible spin states, offers insights into the gas‐phase reaction of plutonium atoms with water. Two possible reactions (isomerization and dehydrogenation) are presented. These reactions are found to be exothermic, with the best thermochemical conditions observed for the dehydrogenation reaction at around 23.5 kcal mol−1. The nature of the chemical‐bonding evolution along the reaction pathways are investigated by employing various methods including electron localization function, atoms in molecules, and Mayer bond order. Total, partial, and overlap population density of state diagrams and analyses are also presented. Reaction rates at elevated temperatures (T=298–2 000 K) are calculated by using variational transition‐state theory with one‐dimensional tunneling effects. In dynamics simulations, only the dehydrogenation reaction is observed, and found to be in good agreement with experimental values.
Biological Production of Muconic Acid via a Prokaryotic 2,3‐Dihydroxybenzoic Acid Decarboxylase
Authors: Sun Xinxiao , Lin Yuheng , Yuan Qipeng , Yan Yajun
Published: July 2014

Non‐oxidative decarboxylases belong to a unique enzyme family that does not require any cofactors. Here we report the characterization of a 2,3‐dihydroxybenzoic acid (2,3‐DHBA) decarboxylase (BDC) from Klebsiella pneumoniae and explore its application on the production of muconic acid. The enzyme properties were systematically studied, including the optimal temperature and pH, kinetic parameters, and substrate specificity. On this basis, we designed an artificial pathway for muconic acid production by connecting 2,3‐DHBA biosynthesis with its degradation pathway. Over‐expression of entCBA and the key enzymes in the shikimate pathway led to the production of 900 mg L−1 of 2,3‐DHBA. Further, expression of the BDC coupled with catechol 1,2‐dioxygenase achieved the conversion of 2,3‐DHBA into muconic acid. Finally, assembly of the total pathway resulted in the de novo production of muconic acid up to 480 mg L−1.
Melatonin administered during the fetal stage affects circadian clock in the suprachiasmatic nucleus but not in the liver
Authors: Houdek Pavel , Polidarová Lenka , Nováková Marta , Matějů Kristýna , Kubík Štěpán , Sumová Alena
Published: July 2014

The mammalian circadian system develops gradually during ontogenesis, and after birth, the system is already set to a phase of the mothers. The role of maternal melatonin in the entrainment of fetal circadian clocks has been suggested, but direct evidence is lacking. In our study, intact or pinealectomized pregnant rats were exposed to constant light (LL) throughout pregnancy to suppress the endogenous melatonin and behavioral rhythms. During the last 5 days of gestation, the rats were injected with melatonin or vehicle or were left untreated. After delivery, daily expression profiles of c‐fos and Avp in the suprachiasmatic nuclei (SCN), and Per1, Per2, Rev‐erbα, and Bmal1 in the liver were measured in 1‐day‐old pups. Due to the LL exposure, no gene expression rhythms were detected in the SCN of untreated pregnant rats or in the SCN and liver of the pups. The administration of melatonin to pregnant rats entrained the pups' gene expression profiles in the SCN, but not in the liver. Melatonin did not affect the maternal behavior during pregnancy. Vehicle injections also synchronized the gene expression in the SCN but not in the liver. Melatonin and vehicle entrained the gene expression profiles to different phases, demonstrating that the effect of melatonin was apparently not due to the treatment procedure per se. The data demonstrate that in pregnant rats with suppressed endogenous melatonin levels, pharmacological doses of melatonin affect the fetal clock in the SCN but not in the liver. © 2014 Wiley Periodicals, Inc. Develop Neurobiol 75: 131–144, 2015
Left atrial volume predicts abnormal exercise left ventricular filling pressure
Authors: Hammoudi Nadjib , Achkar Marc , Laveau Florent , Boubrit Lila , Djebbar Morad , Allali Yann , Komajda Michel , Isnard Richard
Published: July 2014

Aims

Latent heart failure at rest can be observed in a number of patients upon exercise. Considering left atrial (LA) remodelling as the reflection of the cumulative effects of the LV filling pressure (FP) over time, our aim was to investigate whether the LA volume would predict abnormal exercise LVFP.

Methods and results

Ninety patients (58.6 ± 10.8 years, 74 men) underwent exercise echocardiography. The LA maximal volume was measured by the Simpson method and indexed to body surface area. LVFP was assessed by the ratio between early peak diastolic velocities of mitral inflow and the septal annular mitral plane (E/e′). Exercise E/e′ >13 was used as a threshold to define abnormal LVFP. Indexed LA volume was correlated with E/e′ at rest (r = 0.37, P = 0.003), but the correlation was better with exercise E/e′ (r = 0.54, P < 0.0001). In multivariate analysis, age, LV end‐diastolic volume index, LVEF, and exercise E/e′ were the independent determinants of LA volume index (R2 = 0.47, P < 0.0001). Eleven patients had exercise E/e′ >13; compared with the rest of the population, these patients were older and achieved a milder effort. LA volume index >33 mL/m2 predicted an abnormal exercise LVFP with a 91% sensitivity and a 78% specificity. None of the patients with an LA volume index <26 mL/m2 (n = 31, 34%) had an exercise E/e′ >13.

Conclusion

Exercise LVFP is a determinant of LA size. LA volume index seems to be helpful for predicting abnormal exercise LVFP. The potential use of LA remodelling to identify the patients benefitting most from exercise echocardiography should be investigated in larger studies.
Influence of systolic blood pressure on clinical outcomes in elderly heart failure patients treated with nebivolol: data from the SENIORS trial
Authors: Montero‐Perez‐Barquero Manuel , Flather Marcus , Roughton Michael , Coats Andrew , Böhm Michael , Van Veldhuisen Dirk J. , Babalis Daphne , Solal Alain Cohen , Manzano Luis
Published: July 2014

Aims

There is limited information about the effects of beta‐blockers in heart failure (HF) stratified by blood pressure, especially in the elderly and those with preserved EF. We evaluate the effects of nebivolol on outcomes in elderly patients with HF stratified by baseline systolic blood pressure (SBP) and EF.

Methods and results

The SENIORS trial evaluated the effects of nebivolol and enrolled 2128 patients ≥70 years of age with HF. Patients were divided into three baseline pre‐treatment SBP categories (<110, 110–130, and >130 mmHg). In addition, we evaluated the influence of SBP (≤130 and >130 mmHg) on patients with LVEF <40% vs. ≥40%. Low baseline SBP was associated with worse clinical outcomes irrespective of treatment group, both in patients with reduced EF and in those with preserved EF. Nebivolol had similar benefits irrespective of baseline SBP: the hazard ratio (HR) for primary outcome of all‐cause mortality or cardiovascular hospitalization in the three SBP categories for nebivolol vs. placebo was 0.85 [95% confidence interval (CI) 0.50–1.45], 0.79 (95% CI 0.61–1.01), and 0.88 (95% CI 0.72–1.07), respectively (P for interaction = 0.61). Similar results were obtained for the secondary endpoint of all‐cause mortality. There was no significant interaction for the effects of nebivolol by baseline SBP stratified by LVEF.

Conclusions

Elderly HF patients with lower SBP have a worse outcome than those with higher SBP, but nebivolol appears to be safe and well tolerated, with similar benefits on the composite outcome of death or cardiovascular hospital admission irrespective of baseline SBP and LVEF.
Innate immune receptor NOD2 promotes vascular inflammation and formation of lipid‐rich necrotic cores in hypercholesterolemic mice
Authors: Johansson Maria E. , Zhang Xiao‐Ying , Edfeldt Kristina , Lundberg Anna M. , Levin Malin C. , Borén Jan , Li Wei , Yuan Xi‐Ming , Folkersen Lasse , Eriksson Per , Hedin Ulf , Low Hann , Sviridov Dmitri , Rios Francisco J. , Hansson Göran K. , Yan Zhong‐Qun
Published: July 2014

Atherosclerosis is an inflammatory disease associated with the activation of innate immune TLRs and nucleotide‐binding oligomerization domain‐containing protein (NOD)‐like receptor pathways. However, the function of most innate immune receptors in atherosclerosis remains unclear. Here, we show that NOD2 is a crucial innate immune receptor influencing vascular inflammation and atherosclerosis severity. 10‐week stimulation with muramyl dipeptide (MDP), the NOD2 cognate ligand, aggravated atherosclerosis, as indicated by the augmented lesion burden, increased vascular inflammation and enlarged lipid‐rich necrotic cores in Ldlr−/− mice. Myeloid‐specific ablation of NOD2, but not its downstream kinase, receptor‐interacting serine/threonine‐protein kinase 2, restrained the expansion of the lipid‐rich necrotic core in Ldlr−/− chimeric mice. In vitro stimulation of macrophages with MDP enhanced the uptake of oxidized low‐density lipoprotein and impaired cholesterol efflux in concordance with upregulation of scavenger receptor A1/2 and downregulation of ATP‐binding cassette transporter A1. Ex vivo stimulation of human carotid plaques with MDP led to increased activation of inflammatory signaling pathways p38 MAPK and NF‐κB‐mediated release of proinflammatory cytokines. Altogether, this study suggests that NOD2 contributes to the expansion of the lipid‐rich necrotic core and promotes vascular inflammation in atherosclerosis.
Recent Developments in the Chemistry of gem‐Halonitro Compounds
Authors: Soengas Raquel G. , Acúrcio Rita C. , Silva Artur M. S.
Published: July 2014

gem‐Halonitro compounds are valuable synthetic intermediates of growing chemical interest that have been known for many years. Initially, the interest in gem‐halonitro compounds lay in their biological activity, whereas their chemistry remained quite underdeveloped. In the past few years, however, interest in the chemistry of gem‐halonitro compounds has grown exponentially, sparked by some recent investigations into the reactivity of the gem‐halonitro moiety. Nowadays, gem‐halonitro compounds are recognized as powerful chemical tools on account of their usefulness as synthetic intermediates. This review highlights recent synthetic strategies based on gem‐halonitro compounds and provides an overview of their usefulness in organic chemistry.
Chiral Room Temperature Ionic Liquids as Enantioselective Promoters for the Asymmetric Aldol Reaction
Authors: González Laura , Escorihuela Jorge , Altava Belén , Burguete M. Isabel , Luis Santiago V.
Published: July 2014

Chiral ionic liquids derived from natural amino acids are shown to be green and efficient media for direct asymmetric aldol reactions at room temperature catalyzed by (S)‐proline. The corresponding aldol products were obtained with moderate to good enantioselectivities. A transfer of chirality from the chiral reaction media has been observed as well as the participation of match/mismatch interactions of the chiral medium with both enantiomers of proline. Moreover, these catalytic systems were easily recovered by simple filtration, and studies on their reuse have demonstrated that recycling is possible for at least four runs with only a slight reduction in activity.
N‐Acyl‐N‐tosylhydrazine as a Synthon To Construct Tetrasubstituted Carbon Centers Possessing a Nitrogen Group
Authors: Namba Kosuke , Shobo Yoshihiro , Fujimoto Kazuki , Shoji Isamu , Yoshida Masahiro , Tanino Keiji
Published: July 2014

New halohydrazidation and hydrazidopalladation reactions were developed that use the synthon N‐acyl‐N‐tosylhydrazine. The intramolecular bromohydrazidation reactions of β,γ‐unsaturated N‐acyl‐N‐tosylhydrazines readily afforded pyrazolidinone ring systems that contained a tetrasubstituted carbon center, and the primary amine of the N‐acyl‐N‐tosylhydrazine was shown to be a soft nucleophile. The similar bromohydrazidation reaction of γ,δ‐unsaturated N‐acyl‐N‐tosylhydrazine resulted in O‐cyclization to give a lactone ring instead of N‐cyclization to give a hydropyridazine ring system; however, the intramolecular hydrazidopalladation reaction predominantly afforded a hydropyridazine ring. The established catalytic hydrazidopalladation reaction was applicable to several multisubstituted alkenes to construct a tetrasubstituted carbon center possessing a nitrogen group.
Electrochemical Determination of Phenolic Acids at a Zn/Al Layered Double Hydroxide Film Modified Glassy Carbon Electrode
Authors: Kahl Michael , Golden Teresa D.
Published: July 2014

A stable sensor for the determination of gallic acid (GA) and caffeic acid (CA) was fabricated by electrodeposition of Zn‐Al‐NO3 layered double hydroxide film on a glassy carbon electrode (LDHf/GCE). A sensitive electrochemical method was achieved for the determination of GA and CA in a phosphate buffer solution (pH 3). The differential pulse voltammetry response of the LDHf/GCE to GA has a linear concentration range from 4 µM to 600 µM with a correlation coefficient of 0.9985 and the calculated detection limit of 1.6 µM at a signal‐to‐noise ratio of 3. The differential pulse voltammetry response of the LDHf/GCE to CA has a linear concentration range from 7 µM to 180 µM with a correlation coefficient of 0.9969 and the calculated detection limit of 2.6 µM at a signal‐to‐noise ratio of 3. The constructed sensor was applied to the determination of GA in commercial green tea samples.
Double‐injection capillary electrophoresis for the identification of analytes
Authors: Amini Ahmad
Published: July 2014

This paper presents a new approach for identifying analytes by CE. The compound to be identified is analyzed together with the corresponding reference standard during a double injection capillary electrophoretic run. The inter‐plug distance is regulated by applying an electrical field over the capillary for a predetermined time period (tPE). The migration time of an analyte being exposed to the partial electrophoresis was calculated from the partial migration time (tmig(p)) as described in this paper. The identification is based on the closeness of agreement between the calculated migration time (tmig(c)) and observed migration time (tmig) of the reference standard. The validity of the derived equations was checked by analyzing several substances such as caffeine, melamine, acetyl salicylic acid, paracetamol, ibuprofen, metoprolol, naproxen, somatropin, several insulin analogs, as well as different pharmaceutical and natural products. The migration time ratios for the identified solutes varied between 0.996 and 1.006 (i.e., 1.001 ± 0.005), indicating good agreement between the observed and calculated migration times.
Hydraulic “Fracking”: Are surface water impacts an ecological concern?
Authors: Burton G. Allen , Basu Niladri , Ellis Brian R. , Kapo Katherine E. , Entrekin Sally , Nadelhoffer Knute
Published: July 2014

Use of high-volume hydraulic fracturing (HVHF) in unconventional reservoirs to recover previously inaccessible oil and natural gas is rapidly expanding in North America and elsewhere. Although hydraulic fracturing has been practiced for decades, the advent of more technologically advanced horizontal drilling coupled with improved slickwater chemical formulations has allowed extensive natural gas and oil deposits to be recovered from shale formations. Millions of liters of local groundwaters are utilized to generate extensive fracture networks within these low-permeability reservoirs, allowing extraction of the trapped hydrocarbons. Although the technology is relatively standardized, the geographies and related policies and regulations guiding these operations vary markedly. Some ecosystems are more at risk from these operations than others because of either their sensitivities or the manner in which the HVHF operations are conducted. Generally, the closer geographical proximity of the susceptible ecosystem to a drilling site or a location of related industrial processes, the higher the risk of that ecosystem being impacted by the operation. The associated construction of roads, power grids, pipelines, well pads, and water-extraction systems along with increased truck traffic are common to virtually all HVHF operations. These operations may result in increased erosion and sedimentation, increased risk to aquatic ecosystems from chemical spills or runoff, habitat fragmentation, loss of stream riparian zones, altered biogeochemical cycling, and reduction of available surface and hyporheic water volumes because of withdrawal-induced lowering of local groundwater levels. The potential risks to surface waters from HVHF operations are similar in many ways to those resulting from agriculture, silviculture, mining, and urban development. Indeed, groundwater extraction associated with agriculture is perhaps a larger concern in the long term in some regions. Understanding the ecological impacts of these anthropogenic activities provides useful information for evaluations of potential HVHF hazards. Geographic information system–based modeling combined with strategic site monitoring has provided insights into the relative importance of these and other ecoregion and land-use factors in discerning potential HVHF impacts. Recent findings suggest that proper siting and operational controls along with strategic monitoring can reduce the potential for risks to aquatic ecosystems. Nevertheless, inadequate data exist to predict ecological risk at this time. The authors suggest considering the plausibility of surface water hazards associated with the various HVHF operations in terms of the ecological context and in the context of relevant anthropogenic activities. Environ Toxicol Chem 2014;33:1679–1689. © 2014 SETAC
Are flat‐field snow depth measurements representative? A comparison of selected index sites with areal snow depth measurements at the small catchment scale
Authors: Grünewald Thomas , Lehning Michael
Published: July 2014

Single or a limited number of point observations, such as from index stations, are commonly assumed to be representative for the snow cover of larger areas in many applications. This study presents a systematic investigation of the relationship between point observations and areal mean snow depths ranging from the scale of tens of metres to entire catchments. We analyse aerial snow depth information from four mountain regions in the European Alps, one in the Spanish Pyrenees and one in the Canadian Rocky Mountains, obtained from airborne laser scanning surveys. This rich data set allowed to compare point values with snow cover statistics, reflecting the real snow depth distribution of the investigation areas. We present two contrasting approaches in order to assess the representativeness of typical flat‐field snow depth measurements. In the first approach, we define potential index stations based on topographic characteristics as commonly applied for snow cover monitoring stations. The point observations of these index stations are then compared with the mean values in their vicinities. We show that most of the index stations strongly overestimate the snow depth of the catchment and of their surrounding area at distances of several hundreds of metres. Results confirm the expectation that the larger the support area, the smaller the difference to the mean of the complete catchment. The second approach was to analyse topographic characteristics of all cells with snow depths that deviated less than 10% from the catchment mean. It appears that these representative cells are rather randomly distributed and cannot be identified a priori. In summary, our results show large potential biases of index stations with respect to snow distribution and therefore also snow water equivalent. Copyright © 2014 John Wiley & Sons, Ltd.
Identifying the probabilistic structure of drained areas as a function of hypsometry in river networks
Authors: Gsell Pierre‐Stéphane , Le Moine Nicolas , Moussa Roger , Ribstein Pierre
Published: July 2014

Classical morphological descriptors of river networks have been developed in 2D planar system. The third z‐dimension (elevation), however, is necessary to model landscape evolution, particularly in a mountainous region when taking into account transport processes such as in glaciology and erosion. This paper aims at analyzing 3D morphometric properties of channel networks on the basis of probabilistic relationships relating the drained area and the elevation. The methodology is an extension of the fundamental planar power‐law description proposed by Rodriguez‐Iturbe et al. () representing the probability that the drained area A is higher than a threshold area a, P[A > a] ~ a− β, where β is constant and represents an invariant property of natural river networks. A new scaling factor taking into account hypsometry is introduced in the previous power‐law relationship, as , where F is a scaling function and θ is a measure of the system scale and a function of hypsometry. The new power law has one empirical parameter τ. A procedure was developed to calibrate this parameter and to calculate the corresponding uncertainty for applications on a single basin and then extended to a set of 70 basins in the Southern Rocky Mountains. The results show that the 3D power law exhibits scale‐invariance properties with respect to θ, when applied to a single basin. Looking at the entire set of 70 basins, the criterion value associated with the uncertainty model shows a moderate loss in scaling quality compared with the basin‐per‐basin description but nevertheless remains acceptable. This 3D power law provides a geomorphologic basis for applications in mountainous regions where the relation between drained area and hypsometry has to be considered. Copyright © 2014 John Wiley & Sons, Ltd.
Distributed discharge and sediment concentration predictions in the sub‐humid Ethiopian highlands: the Debre Mawi watershed
Authors: Tilahun Seifu A. , Guzman Christian D. , Zegeye Assefa D. , Dagnew Dessalegn C. , Collick Amy S. , Yitaferu Birru , Steenhuis Tammo S.
Published: July 2014

Experimental research in the Ethiopian highlands found that saturation excess induced runoff and erosion are common in the sub‐humid conditions. Because most erosion simulation models applied in the highlands are based on infiltration excess, we, as an alternative, developed the Parameter Efficient Distributed (PED) model, which can simulate water and sediment fluxes in landscapes with saturation excess runoff. The PED model has previously only been tested at the outlet of a watershed and not for distributed runoff and sediment concentration within the watershed. In this study, we compare the distributed storm runoff and sediment concentration of the PED model against collected data in the 95‐ha Debre Mawi watershed and three of its nested sub‐watersheds for the 2010 and 2011 rainy seasons. In the PED model framework, the hydrology of the watershed is divided between infiltrating and runoff zones, with erosion only taking place from two surface runoff zones. Daily storm runoff and sediment concentration values, ranging from 0.5 to over 30 mm and from 0.1 to 35 g l−1, respectively, were well simulated. The Nash Sutcliffe efficiency values for the daily storm runoff for outlet and sub‐watersheds ranged from 0.66 to 0.82, and the Nash–Sutcliffe efficiency for daily sediment concentrations were greater than 0.78. Furthermore, the model uses realistic fractional areas for surface and subsurface flow contributions, for example between saturated areas (15%), degraded areas (30%) and permeable areas (55%) at the main outlet, while close similarity was found for the remaining hydrology and erosion parameter values. One exception occurred for the distinctly greater transport limited parameter at the actively gullying lower part of the watershed. The results suggest that the model based on saturation excess provides a good representation of the observed spatially distributed runoff and sediment concentrations within a watershed by modelling the bottom lands (as opposed to the uplands) as the dominant contributor of the runoff and sediment load. Copyright © 2014 John Wiley & Sons, Ltd.
Population pharmacokinetic modeling and simulation to guide dose selection for RBP‐7000, a new sustained‐release formulation of risperidone
Authors: Laffont Celine M. , Gomeni Roberto , Zheng Bo , Heidbreder Christian , Fudala Paul J. , Nasser Azmi F.
Published: July 2014

RBP‐7000 is a long‐acting formulation of risperidone designed for once‐monthly subcutaneous injection for the treatment of schizophrenia. The objective was to estimate clinically effective doses of RBP‐7000 based on model simulations and on the comparison with other long‐acting injectable antipsychotics. A population pharmacokinetic model of RBP‐7000 was developed in 90 clinically stable schizophrenic patients having received single/repeated doses of 60, 90, or 120 mg. Model simulations were conducted to compare active moiety plasma exposure after repeated RBP‐7000 administrations to the published data of long‐acting risperidone injection (Risperdal® Consta®) at 25 and 50 mg, and of paliperidone palmitate (Invega® Sustenna®) at 50 and 100 mg equivalent paliperidone. Predictions of dopamine D2 receptor occupancy were derived from the simulated active moiety concentrations. Simulations showed similar active moiety plasma exposure at steady‐state for 90 mg of RBP‐7000 and 25 mg of long‐acting risperidone. In comparison to risperidone, RBP‐7000 reached effective concentrations immediately after the first administration. RBP‐7000 at the doses of 60 and 90 mg provided similar active moiety plasma concentrations at steady‐state compared to 50 and 100 mg equivalent paliperidone, respectively. These findings provide guidance for dose selection in Phase III clinical trials and suggest potential benefits for RBP‐7000 over competitors.
Synthesis of 6‐Aryl‐4H‐imidazo[1,2‐b][1,2,4]triazoles and 6‐Aryl‐thiazolo[3,2‐b][1,2,4]triazoles
Authors: Krishnaraj T. , Muthusubramanian S.
Published: July 2014

The cyclization of the derivatives of 3‐aminotriazole, 2‐(5‐substituted 4H‐1,2,4‐triazol‐3‐ylamino)‐1‐arylethanones and 2‐(4H‐1,2,4‐triazol‐3‐ylthio)‐1‐arylethanones to yield 6‐aryl‐4H‐imidazo[1,2‐b][1,2,4]triazoles and 6‐aryl‐thiazolo[3,2‐b][1,2,4]triazoles has been described.
Winter snowfall prediction in the United States using multiple discriminant analysis
Authors: Kluver Daria , Leathers Daniel
Published: July 2014

This study seeks to determine the skill of multiple discriminant analysis for predicting seasonal snowfall. Winter total snowfall amount and frequency of snowfall events are examined for 440 stations in the United States from 1930 to 2006. The independent variables used to create the forecast include ocean–atmosphere teleconnection patterns [such as the Pacific Decadal Oscillation (PDO) and El Niño Southern Oscillation (ENSO)], large‐scale atmospheric patterns [such as the Arctic Oscillation (AO), North Atlantic Oscillation (NAO) and Pacific/North American (PNA)], land cover (such as Arctic sea ice extent and Eurasian snow cover extent), and temperature. Based on a jackknife analysis, forecasts are correct 20–80% of the time for categories of ‘below normal’, ‘near normal’, and ‘above normal’. When broader categories are used of ‘normal or below’, ‘near normal’, and ‘normal or above’ the forecasts are correct as much as 90% of the time at some stations. The Central United States, Ohio River Valley, Great Lakes, and Upper Midwest regions show the highest level of skill. Results not only confirm relationships previously documented between atmospheric phenomena and US snowfall (such as with the PNA, NAO, and ENSO), but also expand our understanding of factors that influence decadal‐scale snowfall variation (such as Arctic sea ice extent and Eurasian snow cover extent).
Raman study of different crystalline forms of PbCrO4 and PbCr1−xSxO4 solid solutions for the noninvasive identification of chrome yellows in paintings: a focus on works by Vincent van Gogh
Authors: Monico Letizia , Janssens Koen , Hendriks Ella , Brunetti Brunetto G. , Miliani Costanza
Published: July 2014

Chrome yellows, a class of pigments frequently used by painters of the Impressionism and Post‐impressionism period, are known for their different chemical stability; the latter depends on the chemical composition (PbCrO4, PbCr1−xSxO4) and crystalline structure (monoclinic or orthorhombic) of the material. The possibility to distinguish among different forms of this pigment is therefore relevant in order to extend knowledge on the corresponding degradation process that is observed on several original paintings. For this purpose, three paintings conserved at the Van Gogh Museum (Amsterdam) were analyzed using noninvasive Raman spectroscopy, while equivalent investigations employing bench‐top instrumentation were performed to obtain information from micro‐samples originating from these works of art. In each painting, the chrome yellow was identified either as monoclinic PbCrO4 or in the form of monoclinic PbCr1−xSxO4 (x < 0.25) or S‐rich orthorhombic PbCr1−xSxO4 (x ~ 0.5). Our ability to make this fairly subtle distinction is based on a Raman study of several oil paint model samples made up of monoclinic and/or orthorhombic crystalline forms of PbCrO4 and PbCr1−xSxO4 (0.1 ≤ × ≤ 0.8). These paints were studied using several excitation wavelengths (namely 785.0, 532.0, 514.5, and 488 nm). Because of the absence of the resonance Raman effect, which strongly enhances the chromate symmetric stretching band, and the absence of any laser‐induced photodecomposition, it is advantageous to acquire data at 785.0 nm. The band‐shape and the position of the chromate bending modes proved to be more sensitive to the solid solution composition and crystalline structure than the stretching modes and can be used as distinctive spectral markers to discriminate among the different chrome yellow forms that are present. Copyright © 2014 John Wiley & Sons, Ltd.
Mallampati class, obesity, and a novel airway trajectory measurement to predict difficult laryngoscopy
Authors: Lee Scott L. , Hosford Clint , Lee Quyen T. , Parnes Steve M. , Shapshay Stanley M.
Published: July 2014

Objectives/Hypothesis

To determine whether Mallampati class correlates with Cormack‐Lehane grade in obese adults, and investigate a novel airway trajectory measurement (ATM) to anticipate difficult laryngoscopy.

Study Design

Retrospective cohort plus a pilot study.

Methods

One hundred eighty‐four nonobese and 160 obese adults underwent laryngoscopy. Spearman correlations, gamma coefficients (G), and Kendall's τ investigated body mass index (BMI):Mallampati, BMI: Cormack‐Lehane, and Mallampati:Cormack‐Lehane. A z test compared the two groups. Twenty‐six volunteers had neck x‐rays taken in the sniffing position to examine trajectories to the larynges (ATM).

Results

Positive predictive value of high Mallampati for difficult laryngoscopy was 8.57%. BMI did not correlate with Mallampati (r = 0.055 [nonobese], r = −0.056 [obese]) or Cormack‐Lehane [r = −0.014 [nonobese], r = −0.022 [obese]). Among nonobese adults, gamma coefficients for BMI:Mallampati was 0.039 (P = .63), for BMI:Cormack‐Lehane was 0.02 (P = .85), and for Mallampati:Cormack‐Lehane was 0.43 (P = .004). Among obese adults, gamma coefficients for BMI:Mallampati was −0.127 (P = .16), for BMI:Cormack‐Lehane was 0.014 (P = .88), and for Mallampati:Cormack‐Lehane was 0.365 (P = .01). Kendall's τ were comparable to gamma coefficients in all analyses. When comparing gamma coefficients for Mallampati:Cormack‐Lehane among the nonobese and obese, z = 0.04 (P = .98). In the ATM study, only Mallampati and upper lip bite test had a significant relationship (G = 1.00, P < .001).

Conclusions

Mallampati correlates poorly with Cormack‐Lehane, regardless of BMI. Pilot data suggest that ATM is feasible.

Level of Evidence

4. Laryngoscope, 125:161–166, 2015
Synthesis of Y‐Shaped Copolymers Containing Phenylborate Ester and Biodegradable Poly(lactic acid) Blocks and Their Glucose‐Sensitive Behavior for Controlled Insulin Release
Authors: Zhao Liyuan , Zhang Xuan , Yao Yuan , Yu Changyuan , Yang Jing
Published: July 2014

This study is devoted to developing amphiphilic, biodegradable, Y‐shaped block polymers, which can self‐assemble to form nanoparticles, as a glucose‐sensitive drug carrier. Y‐shaped poly(ethylene glycol)‐block‐[poly(lactic acid)‐block‐poly (2‐phenylborate esters‐1,3‐dioxane‐5‐methyl) methylacrylate)]2 (MPEG‐(PLA‐block‐PPBDMMA)2) polymers are constructed via a combination of ring‐opening polymerization (ROP) and atom transfer radical polymerization (ATRP) with MPEG‐(OH)2, having double initiation endings, as starting material. These Y‐shaped block polymers can disperse in an aqueous medium and self‐assemble into micellar aggregates with a spherical core–shell structure. Dynamic laser scattering (DLS), zeta potential measurements, and transmission electron microscopy (TEM) show the solution properties of these poly­meric micelles with or without insulin loading. Compared with MPEG‐PLA‐block‐PPBDMMA linear polymer, in vitro insulin release at different glucose concentrations, revealed by the fluorescence technique, shows that the studied Y‐shaped polymers have intelligent glucose‐concentration‐dependent manner of insulin release at pH 7.4 and 37 °C. The bulk swelling phenomenon of the polymeric micelles formed from the Y‐shaped polymers is detected by DLS in the process of their glucose‐responsiveness. Such a Y‐shaped glucose‐responsive polymer is a promising candidate that holds great potential in the treatment of diabetes.

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Relaxation Time at Glass Transition Temperature Measured by Simplex Thermo Stimulated Depolarisation Current
Authors: Bahous Hadj , Soufi Manil M. , Meuret Laurent , Benzohra Mohammed
Published: July 2014

The aim of this work is to propose a reliable approach to estimate values of the relaxation time constant of polymers at the glass transition temperature. This approach consists of using a new thermo stimulated depolarisation current TSDC protocol which analyzes the relaxation current kinetics obtained after submitting the sample to an electrical field shock at constant temperature. The measurements have been performed on a series of polyethylene terephthalate (PET), polycarbonate (PC) and polyethylene terephthalate glycol (PETg) samples. Different temperatures were needed to explore the range of the glass transition domain of each polymer. The results compared to calorimetric and dielectric data show a good agreement. So we confirm that the value τms = 100 s often used for characterizing the molecular dynamic of the liquid glass former at Tg is not universal.
Epoxidation of Styrene/Butadiene Star Block Copolymer by Different Methods and Characterization of the Blends with Epoxy Resin
Authors: Pandit Rajesh , Michler Goerg H. , Lach Ralf , Grellmann Wolfgang , Saiter Jean Marc , Berkessel Albrecht , Adhikari Rameshwar
Published: July 2014

A star shaped polystyrene‐block‐polybutadiene‐block‐polystyrene (SBS) block copolymer was subjected to epoxidation reaction using different reagents such as m‐chloroperoxy benzoic acid (MCPBA), peracetic acid (PAA), performic acid (PFA) and hexaflouro‐isopropanol (HFIP). All the methods led to the targeted modification of the block copolymer satisfactorily, some of them also accompanying rapid side reactions. The epoxidized polymer was then blended with epoxy resin comprising diglycidyl ether of bisphenol‐A in presence of methylene dianiline (MDA) as hardener. The mixing of the epoxidized block copolymer into the epoxy resin led to the formation of well dispersed uniform blend morphology and imparted enhanced thermostability and ductility to the blends. A brittle‐to‐ductile transition was observed in the blends.
Effect of Multiwalled Carbon Nanotubes on the Properties of Poly(methyl methacrylate) in PMMA/CNT Nanocomposites
Authors: Tripathi Sandeep Nath , Singh Sauraj , Malik Rajender Singh , Choudhary Veena
Published: July 2014

In the present paper poly(methyl methacrylate) (PMMA)/multiwall carbon nanotubes (MWCNT) nanocomposites were prepared by bulk polymerization of MMA in presence of varying amounts of MWCNT and 2‐hydroxyethyl methacrylate (HEMA) modified MWCNT (HCNT) using azobisisobutyronitrile (AIBN) as an initiator. The nanocomposites were characterized for their structural, thermal, electrical and morphological behaviour using Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The presence of nanofiller inhibits the formation of head to head linkages as all the nanocomposite samples show two step degradation whereas PMMA prepared under similar condition showed three step degradation. The glass transition temperature (Tg) of PMMA increased after incorporation of MWCNTs. The obtained nanocomposites show an increasing trend in the molecular weight with increase in the wt % of MWCNT whereas it decreases with the increasing initiator concentration. It was observed that the electrical conductivity is the function of molecular weight of the polymer as well as the content of MWCNT in the nanocomposites. The electrical conductivity of PMMA/HCNT composites was slightly lower as compared to PMMA/MWCNT whereas an increasing trend in the storage modulus of PMMA/HCNT nanocomposites was observed.
Biological effects of paenilamicin, a secondary metabolite antibiotic produced by the honey bee pathogenic bacterium Paenibacillus larvae
Authors: Garcia‐Gonzalez Eva , Müller Sebastian , Hertlein Gillian , Heid Nina , Süssmuth Roderich D. , Genersch Elke
Published: July 2014

Paenibacillus larvae is the etiological agent of American Foulbrood (AFB) a world‐wide distributed devastating disease of the honey bee brood. Previous comparative genome analysis and more recently, the elucidation of the bacterial genome, provided evidence that this bacterium harbors putative functional nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs) and therefore, might produce nonribosomal peptides (NRPs) and polyketides (PKs). Such biosynthesis products have been shown to display a wide‐range of biological activities such as antibacterial, antifungal or cytotoxic activity. Herein we present an in silico analysis of the first NRPS/PKS hybrid of P. larvae and we show the involvement of this cluster in the production of a compound named paenilamicin (Pam). For the characterization of its in vitro and in vivo bioactivity, a knock‐out mutant strain lacking the production of Pam was constructed and subsequently compared to wild‐type species. This led to the identification of Pam by mass spectrometry. Purified Pam‐fractions showed not only antibacterial but also antifungal and cytotoxic activities. The latter suggested a direct effect of Pam on honey bee larval death which could, however, not be corroborated in laboratory infection assays. Bee larvae infected with the non‐producing Pam strain showed no decrease in larval mortality, but a delay in the onset of larval death. We propose that Pam, although not essential for larval mortality, is a virulence factor of P. larvae influencing the time course of disease. These findings are not only of significance in elucidating and understanding host–pathogen interactions but also within the context of the quest for new compounds with antibiotic activity for drug development.
The clinical spectrum of anxiety in Parkinson's disease
Authors: Dissanayaka Nadeeka N.N.W. , White Elizabeth , O'Sullivan John D. , Marsh Rodney , Pachana Nancy A. , Byrne Gerard J.
Published: July 2014

Anxiety is common in Parkinson's disease (PD), and contributes to increased disability and poorer quality of life. In spite of its significant impact, the symptomatology, chronology, and neurobiology of anxiety in PD are all poorly understood, and this hinders accurate diagnosis and development of effective treatment strategies. This review investigates and updates literature related to the clinical spectrum of anxiety in PD. The reported prevalence of anxiety in PD varies considerably, with emerging interest in the frequency of the DSM‐IV residual category of “Anxiety disorder, not otherwise specified” (Anxiety disorder NOS), which is observed in up to 25% of PD patients. By design, there are no standardized diagnostic criteria for Anxiety disorder NOS, because this is the category applied to individuals who do not meet diagnostic criteria for any other current anxiety disorder. Anxiety rating scales incompletely capture anxiety symptoms that relate specifically to PD symptoms and the complications arising from PD therapy. Consequently, these scales have been deemed inappropriate for use in PD, and there remains a need for the development of a new PD‐specific anxiety scale. Research establishing accurate symptom profiles of anxiety in PD is sparse, although characterizing such symptomatology would likely improve clinical diagnosis and facilitate targeted treatment strategies. Research into the neurobiological and psychological underpinnings of anxiety in PD remains inconclusive. Anxiety can precede the onset of PD motor symptoms or can develop after a diagnosis of PD. Further investigations focused on the chronology of anxiety and its relationship to PD diagnosis are required. © 2014 International Parkinson and Movement Disorder Society
Nutrikinetic modeling reveals order of genistein phase II metabolites appearance in human plasma
Authors: Smit Suzanne , Szymańska Ewa , Kunz Iris , Roldan Victoria Gomez , van Tilborg Marcel W. E. M. , Weber Peter , Prudence Kevin , van der Kloet Frans M. , van Duynhoven John P. M. , Smilde Age K. , de Vos Ric C. H. , Bendik Igor
Published: July 2014

Scope

Genistein from foods or supplements is metabolized by the gut microbiota and the human body, thereby releasing many different metabolites into systemic circulation. The order of their appearance in plasma and the possible influence of food format are still unknown. This study compared the nutrikinetic profiles of genistein metabolites.

Methods and results

In a randomized cross‐over trial, 12 healthy young volunteers were administered a single dose of 30 mg genistein provided as a genistein tablet, a genistein tablet in low fat milk, and soy milk containing genistein glycosides. A high mass resolution LC‐LTQ‐Orbitrap FTMS platform detected and quantified in human plasma: free genistein, seven of its phase‐II metabolites and 15 gut‐derived metabolites. Interestingly, a novel metabolite, genistein‐4′‐glucuronide‐7‐sulfate (G‐4′G‐7S) was identified. Nutrikinetic analysis using population‐based modeling revealed the order of appearance of five genistein phase II metabolites in plasma: (1) genistein‐4′,7‐diglucuronide, (2) genistein‐7‐sulfate, (3) genistein‐4′‐sulfate‐7‐glucuronide, (4) genistein‐4′‐glucuronide, and (5) genistein‐7‐glucuronide, independent of the food matrix.

Conclusion

The conjugated genistein metabolites appear in a distinct order in human plasma. The specific early appearance of G‐4′,7‐diG suggests a multistep formation process for the mono and hetero genistein conjugates, involving one or two deglucuronidation steps.
Pseudo‐random center placement O‐space imaging for improved incoherence compressed sensing parallel MRI
Authors: Tam Leo K. , Galiana Gigi , Stockmann Jason P. , Tagare Hemant , Peters Dana C. , Constable R. Todd
Published: July 2014

Purpose

Nonlinear spatial encoding magnetic (SEM) field strategies such as O‐space imaging have previously reported dispersed artifacts during accelerated scans. Compressed sensing (CS) has shown a sparsity‐promoting convex program allows image reconstruction from a reduced data set when using the appropriate sampling. The development of a pseudo‐random center placement (CP) O‐space CS approach optimizes incoherence through SEM field modulation to reconstruct an image with reduced error.

Theory and Methods

The incoherence parameter determines the sparsity levels for which CS is valid and the related transform point spread function measures the maximum interference for a single point. The O‐space acquisition is optimized for CS by perturbing the Z2 strength within 30% of the nominal value and demonstrated on a human 3T scanner.

Results

Pseudo‐random CP O‐space imaging is shown to improve incoherence between the sensing and sparse domains. Images indicate pseudo‐random CP O‐space has reduced mean squared error compared with a typical linear SEM field acquisition method.

Conclusion

Pseudo‐random CP O‐space imaging, with a nonlinear SEM field designed for CS, is shown to reduce mean squared error of images at high acceleration over linear encoding methods for a 2D slice when using an eight channel circumferential receiver array for parallel imaging. Magn Reson Med 73:2212–2224, 2015. © 2014 Wiley Periodicals, Inc.