bluuebunny/crossref_metadata_2025 huggingface dataset:
EFFECTS OF ACUTE AND CHRONIC MORPHINE ON DELAY DISCOUNTING IN PIGEONS
Authors: Eppolito Amy K. , France Charles P. , Gerak Lisa R.
Published: April 2013

When reinforcers of different magnitudes are concurrently available, choice is greater for a large reinforcer; that choice can be reduced by delaying its delivery, a phenomenon called delay discounting and represented graphically by a delay curve in which choice is plotted as a function of delay to the large reinforcer. Morphine, administered acutely, can alter responding for large, delayed reinforcers. In this study, the impact of morphine tolerance, dependence and withdrawal on choice of delayed reinforcers was examined in six pigeons responding to receive a small amount of food delivered immediately or a larger amount delivered immediately or after delays that increased within sessions. Acutely, morphine decreased responding for the large reinforcer, and the effect was greater when morphine was administered immediately, rather than 6 hr, before sessions. During 8 weeks of daily administration, morphine produced differential effects across pigeons, shifting the delay curve downward in some and upward in others. In all pigeons, tolerance developed to the response‐rate‐decreasing effects of morphine but not to its effects on delay discounting. When chronic morphine treatment was discontinued, rate of responding decreased in four pigeons, indicating the emergence of withdrawal; choice of the large reinforcer increased, regardless of delay, in all pigeons, an effect that persisted for weeks. These data suggest that chronic morphine administration has long‐lasting effects on choice behavior, which might impact vulnerability to relapse in opioid abusers.
Influence of bed patchiness, slope, grain hiding, and form drag on gravel mobilization in very steep streams
Authors: Scheingross Joel S. , Winchell Eric W. , Lamb Michael P. , Dietrich William E.
Published: April 2013

Steep streams are a major portion of channel networks and provide a link to transport sediment from hillslopes to lower gradient rivers. Despite their importance, key unknowns remain, perhaps foremost of which is evaluating in steep streams empirical laws for fluvial sediment transport developed for low‐gradient rivers. To address this knowledge gap, we painted sediment in situ over 3 years to monitor incipient sediment motion and sediment‐patch development in five small (drainage areas of 0.04–2 km2) and steep (slopes of 5–37%) tributaries of Elder Creek, California, United States. We found that channel beds organized into size‐sorted sediment patches which displayed active fluvial transport of gravel annually, consistent year‐to‐year patch median grain sizes, partial transport of bed material, and significantly higher values of critical Shields stress for incipient sediment motion compared to that observed for lower gradient rivers. The high critical Shields stresses (up to ≈0.5 for the median grain size) agree within a factor of ~3 to theoretical predictions which account for slope‐dependent hydraulics, grain hiding, and sediment patches. For grains of approximately the same size as the roughness length scale, slope‐dependent hydraulics and bed patchiness are the dominant controls on critical Shields stress values, while grain hiding is important for grains larger or smaller than the roughness length scale. Form drag exists in our monitored tributaries but has a smaller influence than the above effects. Our field observations show fluvial processes contribute to sediment mobilization in steep channels which are often considered to be dominated by debris flows.
Synthesis of New 1,3,4‐Oxadiazol, Thiadiazole, 1,2,4‐Triazole, and Arylidene Hydrazide Derivatives of 4‐Oxo‐1,4‐dihydroquinoline with Antimicrobial Evaluation
Authors: El‐Essawy Farag A. , El‐Sayed Wael A.
Published: April 2013

A series of substituted 1,3,4‐oxadiazole, 1,2,4‐triazole, and 1,3,4‐thiadiazole derivatives of the substituted 3‐carboethoxy‐1,4‐dihydro‐4‐oxoquinoline have been synthesized through the reaction of the key intermediate thiosemicarbazide derivatives with different reagents. N′‐Arylidene‐4‐oxo‐1,4‐dihydroquinoline‐3‐carbohydrazides were also synthesized through the condensation reaction of the corresponding hydrazides with the appropriate aldehydes. Antimicrobial activity of some of the synthesized compounds was evaluated.
5‐Amido‐ and 5‐Amino‐Substituted Epoxyisoindolo[2,1‐a]tetrahydroquinolines and 10‐Carboxylic Acids: Their Synthesis and Reactivity
Authors: Zaytsev Vladimir P. , Zubkov Fedor I. , Toze Flavien A. A. , Orlova Daria N. , Eliseeva Maria N. , Grudinin Dmitry G. , Nikitina Eugeniya V. , Varlamov Alexey V.
Published: April 2013

The interactions between 4‐R‐substituted 2‐furyl‐1,2,3,4‐tetrahydroquinolines (synthesized by the Povarov reaction) and a number of alkenes have been investigated. Maleic, dibromomaleic, dichloromaleic, and citraconic anhydrides, as well as acryloyl, methacryloyl, crotonyl, and cynnamoyl chlorides were used as alkene components. It was shown that the initial N‐acylation of the tetrahydroquinolines was followed by a spontaneous [4+2]‐cycloaddition of an N‐acryloyl substituent to the furan ring. It was established that the intramolecular Diels–Alder reaction of furans is reversible, occurs stereoselectively as exo‐addition, and led to target epoxyisoindolo[2,1‐a]tetrahydroquinolines with moderate yields. Oxidation and aromatization of the synthesized products were carried out.
Synthesis of 8‐Oxoberbines and Related Benzolactams by Pd(OAc)2‐Catalyzed Direct Aromatic Carbonylation
Authors: Miyazawa Mamoru , Tokuhashi Takashi , Horibata Akiyoshi , Nakamura Takatoshi , Onozaki Yu , Kurono Nobuhito , Senboku Hisanori , Tokuda Masao , Ohkuma Takeshi , Orito Kazuhiko
Published: April 2013

A variety of alkoxy‐substituted benzolactams with a berbine or yohimbane skeleton were prepared from 1‐benzyl‐1,2,3,4‐tetrahydroisoquinolines or 1‐benzyl‐1,2,3,4‐tetrahydro‐β‐carbolines by a phosphine‐free Pd(II)‐catalyzed direct aromatic carbonylation in a Pd(OAc)2‐Cu(OAc)2 catalytic system. The site selectivity was compared with that of the carbonylation with Pd(OAc)2 or Pd(OAc)2·2 PPh3, respectively.
A Facile Microwave‐Assisted “One‐Pot” Synthesis of Piperazino Pyrimidinyl Acetamides, a Class of Hybrid Bis Heterocycles and Their Structural Elucidation Using NMR Spectral Techniques
Authors: Kanagarajan V. , How Ghee Ang , Siu Choon Ng , Gopalakrishnan M.
Published: April 2013

An array of novel piperazino pyrimidinyl acetamides, a class of hybrid bis heterocycles are synthesized in “one‐pot” by microwave irradiation method catalyzed by heterogeneous NaHSO4.SiO2 catalyst in dry media and are characterized by melting point, elemental analysis, MS, FT‐IR, one‐dimensional NMR (1H and 13C) and two‐dimensional 1H‐1H COSY and 1H‐13C HSQC spectral data.
An Efficient Synthesis of Some New Isolated and Fused Triazole Derivatives
Authors: El Rady Eman A.
Published: April 2013

A facile and efficient route to 5‐hydrazinyl‐3‐phenyl‐3H‐[1,2,4]triazole 2 from the reaction of triazol‐3‐one 1 and hydrazine hydrate is described. In addition, the formation of isolated and fused triazole derivatives was prepared via reaction of 2 with some selected electrophilic reagents in basic medium.
Microwave‐Assisted and Ultrasonic‐Assisted Three‐Component Heterocyclization of 4‐Amino‐5‐carboxamido‐1,2,3‐triazole, Thiopyran‐3‐one‐1,1‐dioxide, and Aromatic Aldehydes
Authors: Gladkov Eugene S. , Desenko Sergey M. , Konovalova Irina S. , Groth Ulrich , Shishkin Oleg V. , Vashchenko Elena V. , Chebanov Valentin A.
Published: April 2013

Three‐component heterocyclization of 4‐amino‐5‐carboxamido‐1,2,3‐triazole, thiopyran‐3‐one‐1,1‐dioxide, and aromatic aldehydes under ultrasonic and microwave irradiation was studied. Regardless of the reaction parameters, 5,6,7,9‐tetrahydro‐4H‐thiopyrano[3,2‐d][1,2,3]triazolo[1,5‐a]pyrimidine‐8,8‐dioxides were isolated as sole reaction products whose structures were proven with help of NMR data and X‐ray analysis.
Reduction of hexavalent chromium by a novel Ochrobactrum sp. – microbial characteristics and reduction kinetics
Authors: Narayani M. , Vidya Shetty K.
Published: April 2013

A Gram negative hexavalent chromium (Cr(VI)) reducing bacteria, Ochrobactrum sp. Cr‐B4 (genbank accession number: JF824998) was isolated from the aerator water of an activated sludge process of a wastewater treatment facility of a dye and pigment based specialty chemical industry. It showed a resistance for 1000 mg L−1 Cr(VI). It exhibited resistance against other heavy metal ions like Ni2+ (900 mg L−1), Cu2+ (500 mg L−1), Pb2+ (800 mg L−1), and Cd2+(250 mg L−1), Zn2+ (700 mg L−1), Fe3+ (800 mg L−1), and against selected antibiotics. Cr‐B4 could efficiently reduce 200 mg L−1 Cr(VI) completely in nutrient and LB media and could convert Cr(VI) to Cr(III) efficiently. Cr(VI) reduction in nutrient media followed allosteric enzyme kinetics with Km values of 59.39 mg L−1 and Vmax values of 47.03 mg L−1 h−1. The reduction in LB media followed Michaelis–Menten kinetics with Km values of 99.52 mg L−1 and Vmax of 77.63 mg L−1 h−1. Scanning electron micrograms revealed the presence of extracellular polymeric secretions.
pH‐dependent effect of pectinase secretion in Penicillium griseoroseum recombinant strains
Authors: Teixeira Janaina Aparecida , Corrêa Thamy Lívia Ribeiro , de Queiroz Marisa Vieira , de Araújo Elza Fernandes
Published: April 2013

A number of parameters, including culture medium pH, affect growth and enzyme production by microorganisms. In the present study, the production and secretion of pectin lyase (PL) and polygalacturonase (PG) by recombinant strains of Penicillium griseoroseum cultured in mineral‐buffered media (MBM; initial pH 6.8) and mineral‐unbuffered medium (MUM; initial pH 6.3) were evaluated. Under these culture conditions, no change in the transcriptional levels of plg1 and pgg2 was observed. However, the levels of secreted total protein ranged from 7.80 ± 1.1 to 3.25 ± 1.50 µg ml−1 in MBM and MUM, respectively, and were evaluated by SDS–PAGE. PL and PG enzymatic activities decreased 6.4 and 3.6 times, respectively, when P. griseoroseum was cultivated under acidic pH conditions (MUM). Furthermore, differences were observed in the hypha and mycelium morphology. These findings suggest that acidic growing conditions affect PL and PG secretion, even though the transcription and translation processes are successful. The data obtained in this study will help to establish optimal culture conditions that increase production and secretion of recombinant proteins by filamentous fungi.
Environmentally safe treatment of black liquor with Comamonas sp. B‐9 under high‐alkaline conditions
Authors: Zheng Yu , Chai Liyuan , Yang Zhihui , Chen Yuehui , Shi Yan , Wang Yangyang
Published: April 2013

The strain Comamonas sp. B‐9 was isolated from steeping fluid of erosive bamboo slips derived from Kingdom Wu during the Three‐Kingdoms Dynasty of ancient China (A.D. 220–280). It could be used to treat black liquor (BL) with high‐alkaline pH and with an initial chemical oxygen demand (COD) of 18,000–25,000 mg L−1, without the addition of other carbon and nitrogen sources. The results revealed that Comamonas sp. B–9 was capable of reducing the COD, color, and lignin content of BL by up to 56.8, 35.3, and 43.5%, respectively. High levels of laccase, manganese peroxidase, cellulase, and xylanase enzymatic activities were also observed, and these enzymes could play an important role in the biotreatment of BL. Further, GC–MS analysis showed that most of the compounds detected in BL after biotreatment with Comamonas sp. B‐9 were diminished, while 4‐methyl benzaldehyde, 3,4,5‐trihydroxybenzoic acid ethyl ester, and 4‐hydroxy‐3,5‐dimethoxy benzaldehyde were produced as metabolites. The presented results indicate that Comamonas sp. B‐9 has potential application for the treatment of wastewaters from pulp and paper processing with high COD load under high‐alkaline conditions.
Bacterial strains isolated from PCB‐contaminated sediments and their use for bioaugmentation strategy in microcosms
Authors: Dudášová Hana , Lukáčová Lucia , Murínová Slavomíra , Puškárová Andrea , Pangallo Domenico , Dercová Katarína
Published: April 2013

This study was focused on the characterization of 15 bacterial strains isolated from long‐term PCB‐contaminated sediment located at the Strážsky canal in eastern part of Slovakia, in the surroundings of a former PCB producer. PCB‐degrading strains were isolated and identified as Microbacterium oleivorans, Stenotrophomonas maltophilia, Brevibacterium sp., Ochrobactrum anthropi, Pseudomonas mandelii, Rhodococcus sp., Achromobacter xylosoxidans, Stenotrophomonas sp., Ochrobactrum sp., Pseudomonas aeruginosa, and Starkeya novella by the 16S rRNA gene sequence phylogenetic analysis. This study presents a newly isolated bacterial strain S. novella with PCB‐degrading ability in liquid medium as well as in sediment. For A. xylosoxidans, the bphA gene was identified. The best growth ability in the presence of all sole carbon sources (biphenyl and PCBs vapor) was obtained for Ochrobactrum sp. and Rhodococcus sp. Uncultured Achromobacter sp. showed the highest potential for bioaugmentation of PCB‐contaminated sediment.
Evaluation of hydroxylamine oxidoreductase as a functional and phylogenetic marker to differentiate Nitrosomonas spp.
Authors: Keluskar Radhika , Desai Anjana
Published: April 2013

Nitrosomonas genus belongs to beta‐subclass of Proteobacteria and encompasses closely related species. Sequence independent techniques like single strand confirmation polymorphism (SSCP) was attempted in the present study to resolve AOB using ammonia monooxygenase (amoA) and hydroxylamine oxidoreductase (hao) gene fragments, unique to AOB. Variation in hydroxylamine oxidoreductase (HAO) enzyme zymogram of isolates observed in the study was also explored as an additional sequence independent method to substantiate the observations. Nitrosomonas europaea (standard strain) and 12 isolates, obtained by enriching environmental samples, were differentiated into six and four groups by SSCP analyses of amoA and hao gene fragments, respectively, whereas they could be resolved into six distinct groups through activity staining of HAO enzyme. amoA gene fragment was therefore found to be better than hao gene fragment in resolving the studied AOB based on richness and evenness with Simpson's index of diversity – 0.85. However, the ensembled use of these molecular methods (SSCP of amoA and hao gene fragments) and HAO enzyme zymogram in fingerprinting AOB provide better resolution and evenness, contributing significantly in AOB diversity studies. Grouping of AOB isolates by hao gene SSCP analysis followed almost the same pattern as that by 16S rRNA gene based sequence analysis, hence it is suitable as a phylogenetic marker.
Bacillus amyloliquefaciens Q‐426 as a potential biocontrol agent against Fusarium oxysporum f. sp. spinaciae
Authors: Zhao Pengchao , Quan Chunshan , Wang Yingguo , Wang Jianhua , Fan Shengdi
Published: April 2013

In recent years, Bacillus species have received considerable attention for the biological control of many fungal diseases. In this study, Bacillus amyloliquefaciens Q‐426 was tested for its potential use against a variety of plant pathogens. Our screen for genes involved in the biosynthesis of antifungal agents revealed that the fen and bmy gene clusters are present in the Q‐426 genome. Lipopeptides such as bacillomycin D, fengycin A, and fengycin B were purified from the bacterial culture broth and subsequently identified by ESI‐mass spectrometry. The minimal inhibitory concentration of fengycin A against Fusarium oxysporum f. sp. spinaciae W.C. Snyder & H.N. Hansen O‐27 was determined to be 31.25 μg ml−1. However, exposure of fungal cells to 50 μg ml−1 of fengycin A did not allow permeation of fluorescein diacetate into the cytoplasm through the cell membrane. Moreover, leakage of intracellular inorganic cations, nucleic acid and protein were also not detected, indicating that the fungal cell membrane is not the primary target of action for fengycin A. Profound morphological changes were observed in the F. oxysporum strain and spore germination was completely inhibited, suggesting that 50 μg ml−1 of fengycin A acts, at least, as a fungistatic agent.
In vitro evaluation of nematophagous activity of fungal isolates
Authors: Nicola Lidia , Tosi Solveig , Savini Dario
Published: April 2013

Four filamentous fungi associated with nematodes were isolated and identified from litter samples collected in the Integral Natural Reserve “Bosco Siro Negri” (PV, Italy): Arthrobotrys dactyloides, Arthrobotrys oligospora var. oligospora, Pochonia bulbillosa, and Pochonia chlamydosporia var. catenulata. Their capacity to break down the nematode population was evaluated in vitro by means of simple and reproducible multiwell plates method. All fungal strains were able to cause a death‐rate significantly different from the controls (p < 0.05). Precisely, A. dactyloides caused, on average, a 26% death rate increase in the nematode population compared to the control, A. oligospora var. oligospora 25%, P. bulbillosa 12%, and P. chlamidosporia var. catenulata 17%. The method has also allowed to determine the more active fungi as regards the prey's life cycle stage. The most active strains against nematodes (adults) were A. dactyloides and A. oligospora var. oligospora, known to attack adults or larval stages by means of tridimensional traps. On the contrary P. bulbillosa and P. chlamydosporia, known to attack mainly the nematode life stage of cysts, showed lower activity against adult nematodes.
Wet‐plate culture studies of Penicillium sp. PT95 and Q1 for mass production of sclerotia
Authors: Zhao Wen‐Jing , An Cui‐Hong , Han Jian‐Rong
Published: April 2013

Penicillium sp. PT95 and Q1 strains were able to form abundant orange, sand‐shaped sclerotia in which carotenoids were accumulated. To determine the potential availability of the wet‐plate method for mass production of sclerotia, nine kinds of liquid media were used culture the PT95 and Q1 strains. The results of the wet‐plate culture showed that on 25% glycerol nitrate broth medium, the growth of both strains was relatively slow, and no sclerotia were found. Q1 strain cultured on Czapek's yeast extract broth medium could not form sclerotia. On other media, both strains could form sclerotia. For PT95 strain, the highest sclerotial biomass (380 mg plate−1) and carotenoids yield (20.88 µg plate−1) could be obtained on Czapek's yeast extract broth and Georgiou's liquid medium, respectively. For Q1 strain, malt extract broth medium gave the highest sclerotial biomass (340 mg plate−1) and omitting iron Joham's liquid medium gave the highest carotenoids yield (18.29 µg plate−1). The results from this study suggest the potential usage of wet‐plate method in the mass production of sclerotia of the PT95 and Q1 strains.
Screening and production of a potent extracellular Arthrobacter creatinolyticus urease for determination of heavy metal ions
Authors: Ramesh Rajendran , Aarthy Mayilvahanan , Gowthaman Marichetti Kuppuswami , Gabrovska Katya , Godjevargova Tzonka , Kamini Numbi Ramudu
Published: April 2013

This paper describes the isolation of a potent extracellular urease producing microorganism, identified by 16S rRNA as Arthrobacter creatinolyticus MTCC 5604 and its medium optimization by classical one‐factor‐at‐a‐time method and central composite rotatable design (CCRD), a tool of response surface methodology (RSM). An optimal activity of 9.0 U ml−1 was obtained by classical method and statistical optimization of the medium resulted in an activity of 17.35 U ml−1 at 48 h and 30 °C. This activity was 4.91 times greater than the initial activity (3.53 U ml−1) from the basal medium and the enzyme showed maximum activity at pH 8.0 and 60 °C and was stable at pH 7.0–9.0 and temperatures up to 50 °C. Furthermore, the enzyme was assessed for its activity reduction by determining the inhibitory concentration (IC50) of heavy metal ions and the inhibition of urease was in the order of Cu(II) > Cd(II) > Zn(II) > Ni(II). Urease was highly sensitive to Cu(II) and its inhibition was 94% and 100% in model solutions containing a mixture of Cu(II) with heavy metal ions Cd(II) and Zn(II), respectively. The results of these studies suggested that the enzyme could be utilized as sensors to determine the levels of Cu(II) ions in industrial effluents, contaminated soil and ground water.
Climatological analysis of December rainfall in the Panama Canal Watershed
Authors: Murphy Michael J. , Georgakakos Konstantine P. , Shamir Eylon
Published: April 2013

Monthly accumulated precipitation over the tropical Panama Canal Watershed has the largest interannual variability in December, with the wettest month on record being December 2010. December accumulated precipitation over the watershed is found to vary with sea surface temperature (SST) anomalies in both the tropical North Atlantic and equatorial Pacific oceans, but a considerably stronger relationship is found with the difference between these SST anomalies. The configuration of SST anomalies in these two ocean basins during December has a strong effect on the flux of low‐level moisture over the Caribbean Sea, southern Central America, and the eastern Pacific Ocean through the modification of the Caribbean Low‐Level Jet (CLLJ) and the Chorro del Occidente Colombiano (CHOCO) jet. Wet Decembers in the watershed are associated with cool (warm) SST anomalies in the tropical Pacific (North Atlantic), a weakening (strengthening) of the CLLJ (CHOCO jet), and increased moisture convergence over and around Panama, with the opposite conditions associated with dry Decembers. The SST anomalies in these two ocean basins affect the distribution of daily precipitation during December differently, with SST anomalies in the Pacific (Atlantic) predominately associated with changes in the frequency of heavier (lighter) precipitation. The analysis shows that December 2010 followed the pattern of associations of wet Decembers but with the highest intensity of precipitation and CHOCO jet strength.
Combined effect of glycation and sodium carbonate–bicarbonate buffer concentration on IgG binding, IgE binding and conformation of ovalbumin
Authors: Ma Xiao‐juan , Gao Jin‐yan , Chen Hong‐bing
Published: April 2013

BACKGROUND

Ovalbumin (OVA) is a major allergen in hen egg. During thermal processing, reducing sugars contained in the hen egg white might easily undergo glycation with OVA, but few studies have been conducted on its corresponding immunoreactivity changes. The aim of the present study was to assess changes of the antigenicity, potential allergenicity and conformation of OVA after glycation in a wet‐thermal processing system under different concentrations of sodium carbonate–bicarbonate buffer.

Results

IgE binding of the glycated OVA was increased after glycation, and the higher the sodium carbonate–bicarbonate buffer concentration, the higher the IgE binding capacity. The increase in IgE binding of OVA corresponded well with the disruption of the disulfide bond, which exposed the epitopes initially buried. Antigenicity of the glycated OVA was increased, and the amount of the increase varied among samples treated under different buffer concentrations.

Conclusion

Glycation increased the allergenic potential for OVA, with the amount of increase varying with different sodium carbonate–bicarbonate buffer concentrations. © 2013 Society of Chemical Industry
Chemical characteristics and biofuels potentials of various plant biomasses: influence of the harvesting date
Authors: Godin Bruno , Lamaudière Stéphane , Agneessens Richard , Schmit Thomas , Goffart Jean‐Pierre , Stilmant Didier , Gerin Patrick A , Delcarte Jérôme
Published: April 2013

BACKGROUND

An optimal valorization of plant biomasses to produce biofuels requires a good knowledge of the available contents and molecular composition of the main chemical components, which changes with the harvesting date. Therefore, we assessed the influence of harvesting date on the chemical characteristics of various energy crops in the context of their conversion to biofuels.

RESULTS

We showed that the biomass chemical composition, enzymatic digestible organic matter, bioethanol and thermal energy production potential for each species are impacted by the harvesting date. The proportion of enzymatically digestible organic matter decreases as the harvesting date is delayed. This is related to the increase in cellulose and lignin contents. The suitability of the biomasses for bioethanol production increases with harvest stage, as the total carbohydrates content increases. The suitability of the biomasses as a source of thermal energy increases according to the harvesting date as the proportion of organic matter increases and the content of mineral compounds decreases. For all investigated energy conversions, the best harvesting period is autumn, because the significantly higher crop dry matter yield largely compensates for the sometimes slightly less favorable chemical characteristics.

CONCLUSION

While the biomass composition of energy crops changes with harvest stage, the dry biomass yield per unit area is the main factor that controls the total amount of chemical components, digestible organic matter, bioethanol and thermal energy that can be expected to be harvested per unit area. The biomass compositions presented in this paper are essential to investigate their suitability for bioenergy conversion. © 2013 Society of Chemical Industry
Selectivity differences of water‐soluble vitamins separated on hydrophilic interaction stationary phases
Authors: Yang Yuanzhong , Boysen Reinhard I. , Hearn Milton T. W.
Published: April 2013

In this study, the retention behavior and selectivity differences of water‐soluble vitamins were evaluated with three types of polar stationary phases (i.e. an underivatized silica phase, an amide phase, and an amino phase) operated in the hydrophilic interaction chromatographic mode with ESI mass spectrometric detection. The effects of mobile phase composition, including buffer pH and concentration, on the retention and selectivity of the vitamins were investigated. In all stationary phases, the neutral or weakly charged vitamins exhibited very weak retention under each of the pH conditions, while the acidic and more basic vitamins showed diverse retention behaviors. With the underivatized silica phase, increasing the salt concentration of the mobile phase resulted in enhanced retention of the acidic vitamins, but decreased retention of the basic vitamins. These observations thus signify the involvement of secondary mechanisms, such as electrostatic interaction in the retention of these analytes. Under optimized conditions, a baseline separation of all vitamins was achieved with excellent peak efficiency. In addition, the effects of water content in the sample on retention and peak efficiency were examined, with sample stacking effects observed when the injected sample contained a high amount of water.
Different Shades of Green: Environmental Management in Hotels in Accra
Authors: Mensah Ishmael
Published: April 2013

This paper assesses the environmental management practices of different categories of hotels in Accra, Ghana. Managers of 200 hotels were surveyed, employing the stratified random sampling method. Results of the study indicate significant differences in the extent of environmental management of the hotels suggesting that the better the quality of a hotel, the better the environmental management performance. Suggestions are made towards improvement in waste management and voluntary environmental programmes in small and medium hotels that did not perform well in those areas of environmental management Copyright © 2013 John Wiley & Sons, Ltd.
Air space reduction tympanomastoidectomy repairs difficult perforations more reliably than tympanoplasty
Authors: Redleaf Miriam I.
Published: April 2013

Objectives/Hypothesis

Air space reduction tympanomastoidectomy improves outcomes over tympanoplasty in repairing tympanic membrane perforations in the presence of unfavorable risk factors.

Study Design

Retrospective review of 67 subjects' 87 operations.

Methods

Interventions were tympanoplasty versus air space reduction tympanomastoidectomy. Risk factors were contracted mastoid air cells, previous failed operations, descent from the indigenous peoples of the Americas, and middle/ear mastoid volumes l<3 CC. Favorable outcomes were closure of the perforation, no decline in hearing, and creation of a self‐cleaning mastoid bowl.

Results

Five out of 46 air space reduction tympanomastoidectomies failed to close their perforations (11%). Pure‐tone threshold (PTA) worsened in 13/46 ears (28%). Four of 46 required mastoid bowl cleaning (9%). In contrast, 21 of 41 tympanoplasties failed to close (51%). PTA worsened in 9/34 ears (26%). All four tympanoplasty failures treated with an air space reduction tympanomastoidectomy closed. Three of the seven tympanoplasty failures treated with a second tympanoplasty did not close. Statistical analysis found two risk factors more prevalent among the air space reduction tympanomastoidectomies: contracted mastoids (P = .019) and middle ear volumes <3 CC (P = .0001). Increased closure of perforations occurring after the air space reduction tympanomastoidectomy was also statistically significant (P = .0002). Descendants of indigenous peoples of the Americas trended toward better PTAs after their air space reduction tympanomastoidectomies than their tympanoplasties and showed statistically significant increases in closure of perforation (P = .0046).

Conclusions

Air space reduction tympanomastoidectomy is an effective and safe method for closing tympanic membrane perforations. © 147.

Level of Evidence

Level of Evidence: 2b Laryngoscope, 124:S1–S13, 2014
Eosinophilic rhinosinusitis is not a disease of ostiomeatal occlusion
Authors: Snidvongs Kornkiat , Chin David , Sacks Raymond , Earls Peter , Harvey Richard J.
Published: April 2013

Objectives/Hypothesis

Ostiomeatal complex (OMC) occlusion may play a role in the pathogenesis of some chronic rhinosinusitis (CRS) subgroups, but its role in diffuse mucosal inflammation is strongly debated. The association between radiological OMC occlusion and its draining sinuses in patients with eosinophilic rhinosinusitis (ECRS) compared to non‐ECRS is investigated.

Study Design

Case‐control study.

Methods

Patients with CRS who underwent endoscopic sinus surgery were investigated. Preoperative computed tomography scans were evaluated. Structured histopathology reporting was performed. The study group was patients with high tissue eosinophil >10/high power fields (HPF), and the control group was patients with low tissue eosinophil ≤10/HPF. The radiological relationship of OMC occlusion to the draining sinuses was analyzed in each group.

Results

Seventy patients with a mean age of 49.7 ± 14.1 years were analyzed. Forty‐one (58.6%) patients had high tissue eosinophil >10/HPF. All patients with ECRS had maxillary disease, and there were 36.2% without OMC occlusion. There was no association of OMC occlusion to either the anterior ethmoid (ECRS: odds ratio [OR], 1.84; 95% confidence interval [CI], 0.24‐14.14; P = .55; non‐ECRS: OR, 1.57; 95% CI, 0.34‐7.33; P = .56) or frontal sinuses (ECRS: OR, 0.67; 95% CI, 0.12‐3.82; P = .65; non‐ECRS: OR, 1.58; 95% CI, 0.45‐5.54; P = .47). For patients with non‐ECRS, maxillary sinus diseases was present in 96.2% of those with OMC occlusion and 50% of those without (OR, 25.0; 95% CI, 2.77‐226.08; P < .001).

Conclusions

OMC occlusion is not associated with draining sinuses for patients with ECRS. Simple surgical interventions directed at the OMC are unlikely to be of benefit to this CRS subgroup.

Level of Evidence

3b.
Parental stress in raising mandarin‐speaking children with cochlear implants
Authors: Chen Yen‐An , Chan Kai‐Chieh , Liao Pei‐Ju , Chen Chin‐Kuo , Wu Che‐Ming
Published: April 2013

Objectives/Hypothesis

To investigate the characteristics of parental stress in the child, parent, and total domains in families of Mandarin‐speaking children with cochlear implants at four different time periods in the implantation process. Previous studies have shown that parental stress lessens after cochlear implantation surgery.

Study Design

Cross‐sectional case series.

Methods

Self‐reported questionnaires based on Abidin's Parenting Stress Index (Taiwanese edition) were filled out by 113 mothers of children with cochlear implants. Factors related to parental stress were analyzed. In addition, we calculated the percentage of families experiencing high levels of stress (percentile ≥90) and compared the differences in stress level between each time period (preoperatively, postoperative time < 2 years, postoperative time between 2 and 5 years, and postoperative time >5 years).

Results

Parent socioeconomic status, patient sex, and patient age were significantly related to the total parental stress. In the study of families experiencing high‐stress between each time period, we found that parents had the highest level of parenting stress during the period of 0 to 2 years postoperatively in the total (odds ratio, 1.89) and child domain (odds ratio, 4.23). The contrary result was found in the parent domain, of which the highest odds ratio was found in the preoperative period.

Conclusions

Although parental stress in the parent domain lessened after the cochlear implantation surgery, parents experienced the highest level of total parental stress during the period of 0 to 2 years postoperatively. The degree of total parenting stress did not lessen after the cochlear implantation surgery.

Level of Evidence

4.
Cochlear implantation for unilateral deafness with and without tinnitus: A case series
Authors: Távora‐Vieira Dayse , Marino Roberta , Krishnaswamy Jay , Kuthbutheen Jafri , Rajan Gunesh P.
Published: April 2013

Objectives/Hypothesis

To investigate cochlear implantation (CI) in patients with unilateral deafness with and without tinnitus.

Study Design

Prospective case series of patients undergoing cochlear implantation for unilateral deafness and tinnitus in a tertiary academic unit.

Methods

Nine postlingually deafened subjects with unilateral hearing loss, with and without tinnitus ipsilaterally, and functional hearing in the contralateral ear were implanted with a standard electrode. Speech perception in noise was tested using the Bamford‐Kowal‐Bench presented at 65 dB SPL. The Speech, Spatial, and Qualities (SSQ) of Hearing Scale was used to evaluate the subjective perception of hearing outcomes, and the Tinnitus Reaction Questionnaire assessed the effect on tinnitus.

Results

All patients were implanted with the Med‐El Flex soft electrode, Innsbruck, Austria. They are regularly wearing the speech processor and find it beneficial in improving their ability to hear, particularly in noise. Decrease of tinnitus perception and an improvement of sound localization sounds were also reported by these patients.

Conclusion

In our case series, CI was successful for all nine patients, with improvement of speech recognition in noise, self‐perceived improvement of hearing, and for tinnitus control. Several factors such as deafness duration, age of deafness onset, the presence of residual hearing, patient motivation, and the rehabilitation intensity need to be further investigated in order to understand their impact on performance after implantation.

Level of Evidence

4.
The use of the facial clinimetric evaluation scale as a patient‐based grading system in bell's palsy
Authors: Ng Jia Hui , Ngo Raymond Yeow Seng
Published: April 2013

Objectives/Hypothesis

The severity of Bell's facial palsy is monitored through physician‐graded instruments, like the House‐Brackmann or Sunnybrook Facial Grading System (FGS). These instruments primarily measure the degree of facial muscle impairment and its resulting asymmetry, but neglect the other functional aspects of facial disability. The aim of this study is therefore to compare the FGS with a patient‐graded quality‐of‐life (QOL) instrument, Facial Clinimetric Evaluation Scale (FaCE).

Study Design

Prospective longitudinal study.

Methods

Twenty‐one patients with newly diagnosed Bell's palsy were recruited. All patients received standard treatment with a corticosteroid. They were scored with the FGS at every visit, and they also completed the FaCE at baseline and when they recovered from their palsy.

Results

At presentation, there was a positive correlation between the FGS score and the total FaCE score (ρ = 0.63, P = .002). However, when individual domains of the FaCE score were analyzed separately, the domains of facial comfort and lacrimal score did not have significant correlation with the FGS. Similarly, at the end of follow‐up, the amount of improvement in FGS and the amount of improvement in the FaCE domains of facial comfort, lacrimal control, and social function showed insignificant and low correlation (P < .05).

Conclusions

This is the first longitudinal study comparing scores on the FGS and FaCE in patients with Bell's palsy. Our findings suggest that without patient‐based QOL assessments such as the FaCE, certain functional aspects of facial disability may be overlooked by physician‐graded instruments, which focus on facial aesthetics.

Level of Evidence

4.
Hearing loss with phosphodiesterase‐5 inhibitors
Authors: Thakur Jagdeep S. , Thakur Somesh , Sharma Dev R. , Mohindroo Narinder K. , Thakur Anamika , Negi Prakash C.
Published: April 2013

Objectives/Hypothesis

To assess the effect of tadalafil on auditory functions.

Study Design

Prospective observational study in a tertiary care hospital.

Methods

Twenty‐five tadalafil naïve patients with erectile dysfunction or pulmonary artery hypertension were subjected to pure‐tone and brainstem‐evoked response audiometry before drug therapy, and 3 and 30 days following drug therapy. Results were compared using analysis of variance for repeated measures with Bonferonni correction.

Results

Fifteen patients were taking tadalafil 10 mg for erectile dysfunction, and another 10 patients were on tadalafil 20 mg once daily for pulmonary artery hypertension. No statistically significant difference was found in hearing threshold at baseline and at follow‐up (P > .05). However, three patients on tadalafil 20 mg showed a significant increase in hearing threshold at higher frequencies. There was no incidence of sudden sensorineural hearing loss in the study group.

Conclusions

This is the first prospective and observational study that evaluated the effect of tadalafil on auditory functions with objective tests. Although there was no statistically significant result to confirm or refute the association between tadalafil and hearing impairment, increased threshold at higher frequencies after taking tadalafil supports the results from previous studies and hints at a possible relationship between the two. Similar large sample studies are warranted to know the exact association of phosphodiesterase‐5 inhibitors on auditory functions.

Level of Evidence

4.
The Effects of topical anesthetic on swallowing during nasoendoscopy
Authors: Lester Scott , Langmore Susan E. , Lintzenich Catherine R. , Wright S. Carter , Grace‐Martin Karen , Fife Tim , Butler Susan G.
Published: April 2013

Objectives/Hypothesis

To assess the effects of a typical otolaryngologic dose of 1 mL of 4% lidocaine on penetration aspiration scale scores and participant discomfort during flexible endoscopic evaluation of swallowing.

Study Design

A prospective pilot study.

Methods

Twenty healthy participants consumed 12 swallows consisting of graduated volumes of milk, water, pudding, and cracker in anesthetized and nonanesthetized conditions. Each participant was randomly selected to begin with the anesthetized or nonanesthetized condition. Each participant returned within 7 days to repeat the study in the other condition. Digital recordings of their evaluations were scored via the penetration‐aspiration scale in a blinded fashion. Participants recorded their discomfort and tolerance of each flexible endoscopic evaluation of swallowing.

Results

The anesthetized condition yielded significantly worse swallowing function (P = .001) than the nonanesthetized condition. The nonanesthetized condition yielded greater discomfort and pain during the procedure (P = .006, .018), greater pain during insertion and removal of the endoscope (P = .002, .003) and less overall tolerance (P = .016) than the anesthetized condition.

Conclusions

A typical otolaryngologic anesthetic dose of 1 mL of 4% lidocaine during flexible endoscopic evaluation of swallowing predisposed healthy young adults to higher penetration aspiration scale scores (less safe swallowing) than the nonanesthetized condition; however, the anesthetic reduced discomfort and provided better overall tolerance. Future studies need to evaluate the effects of lower doses of lidocaine (0.2 and 0.5 mL) on swallowing function and comfort.

Level of Evidence

4. Laryngoscope, 2012
Clinical predictors of post–liver transplant new-onset heart failure
Authors: Qureshi Waqas , Mittal Chetan , Ahmad Umair , Alirhayim Zaid , Hassan Syed , Qureshi Sophia , Khalid Fatima
Published: April 2013

Objectives of this study were (1) to evaluate preoperative predictors of systolic and diastolic heart failure in patients undergoing liver transplantation (LT) and (2) to describe the prognostic implications of systolic and diastolic heart failure in these patients. The onset of heart failure after orthotopic LT remains poorly understood. Data were obtained for all LT recipients between January 2000 and December 2010. The primary outcome was post-LT heart failure: systolic (ejection fraction ≤ 50%), diastolic, or mixed heart failure. Patients underwent echocardiographic evaluation before and after LT. Pretransplant variables were evaluated as predictors of heart failure with Cox proportional hazards model. 970 LT recipients were followed for 5.3 ± 3.4 years. Ninety-eight patients (10.1%) developed heart failure in the posttransplant period. There were 67 systolic (6.9%), 24 diastolic (2.5%), and 7 mixed systolic/diastolic (0.7%) heart failures. Etiology was ischemic in 18 (18.4%), tachycardia-induced in 8 (8.2%), valvular in 7 (7.1%), alcohol-related in 4 (4.1%), hypertensive heart disease in 3 (3.1%), and nonischemic in majority of patients (59.2%). Pretransplant grade 3 diastolic dysfunction, diabetes, hypertension, mean arterial pressure ≤ 65 mm Hg, mean pulmonary artery pressure ≥ 30 mm Hg, mean pulmonary capillary wedge pressure ≥ 15 mm Hg, hemodialysis, brain natriuretic peptide level and QT interval > 450 ms were found to be predictive for the development of new-onset systolic heart failure. However beta-blocker use before LT and tacrolimus after LT were associated with reduced development of new-onset systolic heart failure. In conclusion, pretransplant risk factors, hemodynamic variables, and echocardiographic variables are important predictors of post-LT heart failure. In patients undergoing LT, postoperative onset of systolic or diastolic heart failure was found to be an independent predictor of mortality. Liver Transpl 19:701–710, 2013. © 2013 AASLD.
ZnIIBisterpyridine Metallopolymers: Improved Processability by the Introduction of Polymeric Side Chains
Authors: Wild Andreas , Teichler Anke , von der Ehe Christian , Winter Andreas , Hager Martin D. , Yao Bing , Zhang Baohua , Xie Zhiyuan , Wong Wai‐Yeung , Schubert Ulrich S.
Published: April 2013

Introducing well‐defined polymeric side chains to bisterpyridine coordination polymers enables the synthesis of materials with tailor‐made optical and mechanical properties. The polymers are introduced either by a copper‐catalyzed azide–alkyne cycloaddition (grafting‐onto) or an atom transfer radical polymerization (polymerization‐from) method. The resulting metallopolymers exhibit improved solubility in common organic solvents and can, therefore, be inkjet‐printed from chlorinated benzene solutions. The photophysical properties of the so‐produced homogeneous films are investigated and a proof‐of‐principle polymer light‐emitting device can be constructed.

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On the tangential Cauchy‐Fueter operators on nondegenerate quadratic hypersurfaces in \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}${\mathbb {H}^2}$\end{document}
Authors: Wang Wei
Published: April 2013

On quadratic hypersurfaces in \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathbb {H}^2$\end{document}, we find the explicit forms of tangential Cauchy‐Fueter operators and associated tangential Laplacians □b. Then by using the Fourier transformation on the associated nilpotent Lie groups of step two, we construct the relative fundamental solutions to the tangential Laplacians and Szegö kernels on the nondegenerate quadratic hypersurfaces. It is different from the complex case that the quaternionic tangential structures on the nondegenerate quadratic hypersurfaces in \documentclass{article}\usepackage{amssymb}\begin{document}\pagestyle{empty}$\mathbb {H}^2$\end{document} cannot be reduced to one standard model and the non‐homogeneous tangential Cauchy‐Fueter equations are solvable even in many convex cases.
Pathological gambling in Parkinson's disease: Subthalamic oscillations during economics decisions
Authors: Rosa Manuela , Fumagalli Manuela , Giannicola Gaia , Marceglia Sara , Lucchiari Claudio , Servello Domenico , Franzini Angelo , Pacchetti Claudio , Romito Luigi , Albanese Alberto , Porta Mauro , Pravettoni Gabriella , Priori Alberto
Published: April 2013

Pathological gambling develops in up to 8% of patients with Parkinson's disease. Although the pathophysiology of gambling remains unclear, several findings argue for a dysfunction in the basal ganglia circuits. To clarify the role of the subthalamic nucleus in pathological gambling, we studied its activity during economics decisions. We analyzed local field potentials recorded from deep brain stimulation electrodes in the subthalamic nucleus while parkinsonian patients with (n = 8) and without (n = 9) pathological gambling engaged in an economics decision‐making task comprising conflictual trials (involving possible risk‐taking) and non conflictual trials. In all parkinsonian patients, subthalamic low frequencies (2–12 Hz) increased during economics decisions. Whereas, in patients without gambling, low‐frequency oscillations exhibited a similar pattern during conflictual and non conflictual stimuli, in those with gambling, low‐frequency activity increased significantly more during conflictual than during non conflictual stimuli. The specific low‐frequency oscillatory pattern recorded in patients with Parkinson's disease who gamble could reflect a subthalamic dysfunction that makes their decisional threshold highly sensitive to risky options. When parkinsonian patients process stimuli related to an economics task, low‐frequency subthalamic activity increases. This task‐related change suggests that the cognitive‐affective system that drives economics decisional processes includes the subthalamic nucleus. The specific subthalamic neuronal activity during conflictual decisions in patients with pathological gambling supports the idea that the subthalamic nucleus is involved in behavioral strategies and in the pathophysiology of gambling. © 2013 International Parkinson and Movement Disorder Society