bluuebunny/crossref_metadata_2025 huggingface dataset:
Bioaccumulation, stress, and swimming impairment in Daphnia magna exposed to multiwalled carbon nanotubes, graphene, and graphene oxide
Authors: Cano Amanda M. , Maul Jonathan D. , Saed Mohammad , Shah Smit A. , Green Micah J. , Cañas-Carrell Jaclyn E.
Published: February 2017

The use of carbon-based nanomaterials (CNMs) such as multiwalled carbon nanotubes (MWCNTs), graphene, and graphene oxide (GO) is increasing across many applications because of their unique and versatile properties. These CNMs may enter the aquatic environment through many pathways, creating the potential for organism exposure. The present study addresses the bioaccumulation and toxicity seen in Daphnia magna exposed to CNMs dispersed in sodium dodecyl benzene sulfonate (SDBS). In study I, D. magna were exposed to varying outer diameters of MWCNTs for 24 h in moderately hard or hard freshwater. Bioaccumulation of MWCNT was found in all treatments, with the highest concentrations (0.53 ± 0.27 μg/g) in D. magna exposed in hard freshwater (p < 0.005). The median lethal concentration (LC50) was determined for D. magna exposed to CNMs in moderately hard and hard freshwater. In study II, D. magna were exposed to CNMs for 72 h in moderately hard freshwater to assess swimming velocity and generation of reactive oxygen species (ROS) detected by dichlorofluorescein fluorescence. An overall decrease was seen in D. magna swimming velocity after exposure to CNMs. The generation of ROS was significantly higher (1.54 ± 0.38 dichlorofluorescein mM/mg dry wt) in D. magna exposed to MWCNTs of smaller outer diameters than in controls after 72 h (p < 0.05). These results suggest that further investigation of CNM toxicity and behavior in the aquatic environment is needed. Environ Toxicol Chem 2017;36:2199–2204. © 2017 SETAC
Long-term effects of fungicides on leaf-associated microorganisms and shredder populations—an artificial stream study
Authors: Zubrod Jochen P. , Englert Dominic , Wolfram Jakob , Rosenfeldt Ricki R. , Feckler Alexander , Bundschuh Rebecca , Seitz Frank , Konschak Marco , Baudy Patrick , Lüderwald Simon , Fink Patrick , Lorke Andreas , Schulz Ralf , Bundschuh Mirco
Published: February 2017

Leaf litter is a major source of carbon and energy for stream food webs, while both leaf-decomposing microorganisms and macroinvertebrate leaf shredders can be affected by fungicides. Despite the potential for season-long fungicide exposure for these organisms, however, such chronic exposures have not yet been considered. Using an artificial stream facility, effects of a chronic (lasting up to 8 wk) exposure to a mixture of 5 fungicides (sum concentration 20 μg/L) on leaf-associated microorganisms and the key leaf shredder Gammarus fossarum were therefore assessed. While bacterial density and microorganism-mediated leaf decomposition remained unaltered, fungicide exposure reduced fungal biomass (≤71%) on leaves from day 28 onward. Gammarids responded to the combined stress from consumption of fungicide-affected leaves and waterborne exposure with a reduced abundance (≤18%), which triggered reductions in final population biomass (18%) and in the number of precopula pairs (≤22%) but could not fully explain the decreased leaf consumption (19%), lipid content (≤43%; going along with an altered composition of fatty acids), and juvenile production (35%). In contrast, fine particulate organic matter production and stream respiration were unaffected. Our results imply that long-term exposure of leaf-associated fungi and shredders toward fungicides may result in detrimental implications in stream food webs and impairments of detrital material fluxes. These findings render it important to understand decomposer communities’ long-term adaptational capabilities to ensure that functional integrity is safeguarded. Environ Toxicol Chem 2017;36:2178–2189. © 2017 SETAC
In Vitro Evaluation of High‐Level, Gentamicin‐Resistant Enterococci Isolated from Bacteremic Patients
Authors: Wiland Anne M. , Plaisance Karen I. , Schwalbe Richard S.
Published: February 2017

We attempted to characterize the susceptibility of high‐level, gentamicin‐resistant (HLGR, minimum inhibitory concentration [MIC] >2000 μg/ml) enterococcal blood isolates and evaluated a small subset of these isolates for bactericidal synergy. Thirteen Enterococcus faecalis and three Enterococcus faecium isolates that were HLGR were prospectively collected. Standard broth macrodilution techniques were used to determine the MICs and minimum bactericidal concentrations to a variety of antibiotics. Two isolates were evaluated for synergy by time‐kill curve methods using combinations of penicillin and streptomycin, teicoplanin and rifampin, and vancomycin and ciprofloxacin. Teicoplanin was the most active antibiotic tested, with all isolates exhibiting susceptibility to this agent. Four E. faecalis isolates and one E. faecium isolate expressed only low‐level resistance to streptomycin (LLSR, MlCs 32–64 μg/ml). Penicillin and streptomycin produced bactericidal synergy in the LLSR isolate. The other antibiotic combinations did not result in bactericidal synergy in the two isolates tested. For HLGR enterococci that are only LLSR, the combination of penicillin‐streptomycin appears to provide adequate bactericidal activity. Teicoplanin may potentially be useful for streptomycin‐resistant HLGR isolates.
Cortisol Pharmacodynamic Response to Long‐Term Methylprednisolone in Renal Transplant Recipients
Authors: Tornatore Kathleen M. , Reed Kristine , Walshe J. Joseph , Venuto Rocco C.
Published: February 2017

Study Objective. To examine the pharmacodynamic patterns of cortisol and pharmacokinetic values of long‐term methylprednisolone in renal transplant recipients.

Design. Twenty‐four‐hour pharmacokinetic and pharmacodynamic evaluation of patients who participated in a glucocorticoid‐monitoring program.

Setting. University‐based renal transplant clinic.

Patients. Fourteen renal transplant recipients studied during a clinically stable period.

Interventions. The daily oral methylprednisolone dose for each patient was administered intravenously and serial plasma cortisol and methylprednisolone samples were obtained over 24 hours.

Measurements and Main Results. Methylprednisolone was analyzed by high‐performance liquid chromatography. The baseline morning cortisol serum concentrations ranged from 9.8–210.7 ng/ml. After the drug was administered, cortisol declined in a linear fashion with a mean suppression half‐life of 2.4 ± 0.9 hours. The cortisol nadir was reached at 12–16 hours in 11 of 14 patients. The return cortisol area under the curve (AUC‐Cret) was noted in all patients and ranged from 57–987 ng·hr/ml. The total cortisol area under the curve was greater in patients who had been transplanted for longer than 2 years (1676 ± 252 vs 836 ± 405 ng·hr/ml; p<0.05) compared with more recently transplanted patients. Methylprednisolone clearance ranged from 100–1181 ml/hr/kg with a mean volume of distribution of 1.3 ± 0.6 L/kg. The methylprednisolone half‐life ranged from 1.2–4.7 hours. The correlation between AUC‐Cret and methylprednisolone AUC was −0.64 (p<0.05).

Conclusions. The pharmacodynamic response of cortisol in renal transplant recipients may be associated in part with long‐term steroid exposure. However, the interrelationship between the endocrine and immune system may also affect cortisol's disposition and subsequent recovery patterns in this population. Considerable interpatient variability was apparent in both the cortisol pharmacodynamic response as well as the pharmacokinetics of methylprednisolone. These findings suggest a more individualized dosing method may be necessary to optimize the immunosuppressive effect of glucocorticoids and minimize clinical toxicity.
Deubiquitinating enzyme USP22 positively regulates c‐Myc stability and tumorigenic activity in mammalian and breast cancer cells
Authors: Kim Dongyeon , Hong Ahyoung , Park Hye In , Shin Woo Hyun , Yoo Lang , Jeon Seo Jeong , Chung Kwang Chul
Published: February 2017

The proto‐oncogene c‐Myc has a pivotal function in growth control, differentiation, and apoptosis and is frequently affected in human cancer, including breast cancer. Ubiquitin‐specific protease 22 (USP22), a member of the USP family of deubiquitinating enzymes (DUBs), mediates deubiquitination of target proteins, including histone H2B and H2A, telomeric repeat binding factor 1, and cyclin B1. USP22 is also a component of the mammalian SAGA transcriptional co‐activating complex. In this study, we explored the functional role of USP22 in modulating c‐Myc stability and its physiological relevance in breast cancer progression. We found that USP22 promotes deubiquitination of c‐Myc in several breast cancer cell lines, resulting in increased levels of c‐Myc. Consistent with this, USP22 knockdown reduces c‐Myc levels. Furthermore, overexpression of USP22 stimulates breast cancer cell growth and colony formation, and increases c‐Myc tumorigenic activity. In conclusion, the present study reveals that USP22 in breast cancer cell lines increases c‐Myc stability through c‐Myc deubiquitination, which is closely correlated with breast cancer progression.
Molecular pathogenesis in chronic obstructive pulmonary disease and therapeutic potential by targeting AMP‐activated protein kinase
Authors: Zhang Zhihui , Cheng Xiaoyu , Yue Li , Cui Wenhui , Zhou Wencheng , Gao Jian , Yao Hongwei
Published: February 2017

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide, which is characterized by a persistent airflow limitation caused by chronic inflammatory responses to noxious particles or gases. Cigarette smoke and environmental pollutions are major etiological factors for causing COPD. It has been shown that cigarette smoking causes abnormal inflammatory responses, cellular senescence, mitochondrial dysfunction and metabolic dysregulation, suggesting their involvement in the development of COPD. Although the medical care and treatment have advanced, there are no effective therapies to stop or reverse lung destruction in COPD/emphysema. AMP‐activated protein kinase (AMPK) is a serine threonine kinase with α, β, and γ subunits that are highly conserved through evolution. AMPK has been shown to regulate bioenergetics, inflammatory responses, senescence, and metabolism. This review focused on the updated understanding of molecular pathogenesis of COPD, and highlighted the crucial roles of AMPK in lung abnormalities as well as discussed the potential therapeutics of AMPK activators in preventing and halting the progression of COPD.
A prognostic 4‐gene expression signature for squamous cell lung carcinoma
Authors: Li Jun , Wang Jing , Chen Yanbin , Yang Lijie , Chen Sheng
Published: February 2017

Squamous cell lung carcinoma (SQCLC), a common and fatal subtype of lung cancer, caused lots of mortalities and showed different outcomes in prognosis. This study was to screen key genes and to figure a prognostic signature to cluster the patients with SQCLC. RNA‐Seq data from 550 patients with SQCLC were downloaded from The Cancer Genome Atlas (TCGA). Genetically changed genes were identified and analyzed in univariate survival analysis. Genes significantly influencing prognosis were selected with frequency higher than 100 in lasso regression. Meanwhile, area under the curve (AUC) values and hazard ratios (HR) for seed genes were obtained with R Language. Functional enrichment analysis was performed and clustering effectiveness of the selected common gene set was analyzed with Kaplan–Meier. Finally, the stability and validity of the optimal clustering model were verified. A total of 7,222 genetically changed genes were screened, including 1,045 ones with p < 0.05, 1,746, p < 0.1, and 2,758, p < 0.2. The common gene sets with more than 100 frequencies were 14‐Genes, 10‐Genes and 6‐Genes. Genes with p < 0.05 participated in positive regulation of ERK1 and ERK2 cascade, angiogenesis, platelet degranulation, cell–matrix adhesion, extracellular matrix organization, macrophage activation, and so on. A four‐gene clustering model in 14‐Genes (DPPA, TTTY16, TRIM58, HKDC1, ZNF589, ALDH7A1, LINC01426, IL19, LOC101928358, TMEM92, HRASLS, JPH1, LOC100288778, GCGR) was verified as the optimal. The discovery of four‐gene clustering model in 14‐Genes can cluster the patient samples effectively. This model would help predict the outcomes of patients with SQCLC then improve the treatment strategies.
A novel preservative‐free seasonal influenza vaccine safety and immune response study in the frame of preclinical research
Authors: Sarsenbayeva Gulbanu , Volgin Yevgeniy , Kassenov Markhabat , Issagulov Timur , Bogdanov Nikolay , Nurpeisova Ainur , Sagymbay Altynay , Abitay Ruslan , Stukova Marina , Sansyzbay Abylay , Khairullin Berik
Published: February 2017

The paper describes the results of preclinical testing of the preparation “Vaccine allantoic split‐virus inactivated against seasonal influenza.” Acute toxicity and local irritating effect, anaphylactic reactions to different antigens (vaccine and ovalbumin), delayed‐type hypersensitivity to ram erythrocytes, humoral immune response in hemaggtination reaction, immunogenic activity was studied in laboratory animals of various species (mice, rats, guinea pigs). Comparative analysis of the results from testing immunogenic activity of the preparation under study and the commercial influenza vaccines was performed. The preclinical testing has demonstrated safety and immune response of the seasonal split influenza vaccine, so it may be recommended for clinical study on limited contingent of volunteers.
From IRIOP to the JOB Annual Review: The past and future of a venerable outlet
Authors: Harvey Paul , Dasborough Marie
Published: February 2017

As incoming co‐editors, we introduce the 2017 International Review of Industrial and Organizational Psychology (IRIOP) Annual Review Issue. We begin this editorial with a brief history of IRIOP, from its creation as a book series in 1986 to the present issue—its fifth as an annual Journal of Organizational Behavior publication. We also summarize several changes we will be implementing, including expanded page limits for submissions and a name change. Most importantly, we then introduce the six manuscripts that appear in this issue. These papers, selected by former editors Gerard Hodgkinson and Kevin Ford, carry on the tradition of high‐quality, impactful reviews that IRIOP has published for the past 30 years. Copyright © 2017 John Wiley & Sons, Ltd.
Preoperative β‐blockade and hypertension in the first hour of functional endoscopic sinus surgery
Authors: Schechtman Samuel A. , Wertz Aileen P. , Shanks Amy , Thompson Aleda , Tremper Kevin , Pynnonen Melissa A. , Healy David W.
Published: February 2017

Objectives/Hypothesis

Local anesthetic with epinephrine is commonly injected into the nasal mucosa during functional endoscopic sinus surgery (FESS). Systemic absorption of epinephrine following local injection may occur, resulting in a mild sympathetic response. This study seeks to determine whether an exaggerated sympathetic response to epinephrine is demonstrated in patients undergoing FESS treated preoperatively with established pharmacologic beta (β) adrenoceptor blockade.

Study Design

A retrospective analysis of adult patients undergoing FESS at a tertiary care university hospital.

Methods

The primary outcome was the occurrence of an exaggerated hypertensive response within the first hour of surgical time defined by a relative increase (>20%) in the first measured intraoperative systolic blood pressure (SBP) prior to induction of anesthesia, or a single SBP value above 200 mm Hg. A mixed effects logistic regression model was developed to identify independent predictors of an exaggerated hypertensive response and describe the variance in the outcome attributable to the surgeon and anesthesiologist.

Results

There were 2,051 patients identified. Independent predictors of an exaggerated intraoperative hypertensive event included: preoperative β‐blocker use (adjusted odds ratio [AOR]: 3.33), female gender (AOR: 1.92), body mass index (AOR: 1.03), lower baseline SBP (AOR: 0.93), and advanced age (AOR: 1.03). The C statistic for the model was 0.8881.

Conclusions

Preoperative β‐blocker use is an independent predictor of an exaggerated hypertensive response within the first hour of operative time. An exaggerated hypertensive effect should be anticipated in patients presenting for FESS with established pharmacologic β‐blockade, and caution should be applied to use of epinephrine‐containing solutions.

Level of Evidence

4. Laryngoscope, 127:1496–1505, 2017
Soil Reserves of Potassium: Release and Availability to Lolium perenne in Relation to Clay Minerals in Six Cropland Soils from Eastern China
Authors: Li Ting , Wang Huoyan , Chen Xiaoqin , Zhou Jianmin
Published: February 2017

An 8‐month greenhouse experiment with ryegrass (Lolium perenne L.) examined the relationship between the dynamics of potassium (K) reserves in soil and changes in clay minerals, using X‐ray diffraction. The capacity of soil to release K was consistent with its ability to supply it and was the highest in the soil samples collected from Laiyang (H1T2a), Harbin (H1T1) and Beibei (H2T4), followed by the sample from Jiangyan (H1T2b), and the lowest in the samples from Gao'an (H2T3a) and Wangcheng (H2T3b). Removal of soil K decreases the intensity of reflections for illite and increases that for interstratified clay minerals. The centre of gravity values of the clay fractions was significantly negatively correlated to the depletion of soil K reserves, as ascertained through chemical extraction or through plant action. The quantitative regression equations between the centre of gravity values and the dynamics of soil reserves of K can be used for predicting the release and plant availability of K even without growing a crop. Copyright © 2017 John Wiley & Sons, Ltd.
Role of internal waves on mixing, nutrient supply and phytoplankton community structure during spring and neap tides in the upwelling ecosystem of Ría de Vigo (NW Iberian Peninsula)
Authors: Villamaña Marina , Mouriño‐Carballido Beatriz , Marañón Emilio , Cermeño Pedro , Chouciño Paloma , da Silva José C. B. , Díaz Patricio A. , Fernández‐Castro Bieito , Gilcoto Miguel , Graña Rocío , Latasa Mikel , Magalhaes Jorge M. , Luis Otero‐Ferrer José , Reguera Beatriz , Scharek Renate
Published: February 2017

Despite evidence of internal waves in the NW Iberian upwelling region, their action and role on nutrient supply dynamics and phytoplankton community structure remain unexplored. A multidisciplinary approach, combining analysis of Synthetic Aperture Radar (SAR) images acquired during the summer months of 2008–2011, together with high‐frequency samplings carried out in the Ría de Vigo in August 2013 during spring (CHAOS1) and neap tides (CHAOS2), was used to characterize: (1) the internal wave activity, (2) its influence on mixing and nutrient supply, and (3) its role on phytoplankton community. SAR images revealed that internal waves were more energetic during spring tides. Turbulent mixing was higher during CHAOS1‐springs (Kz =1.3 [1.0–2.0, 95% confidence interval] × 10−3 m2 s−1) compared to CHAOS2‐neaps (Kz = 0.7 [0.5–1.0] × 10−3 m2 s−1), and as a result nitrate diffusive fluxes were approximately fourfold higher (35 [17–73] mmol m−2 d−1) during CHAOS1‐springs. The sampling covered a transition from relaxation‐stratification (CHAOS1‐springs) to intensifying upwelling (CHAOS2‐neaps) conditions, resulting in nitrate supply (including both diffusive and advective fluxes) being about 50% higher during CHAOS2‐neaps. The phytoplankton community, which was overwhelmingly dominated by diatoms in both cruises, exhibited a shift in species composition, with an increase in the abundance of large Chaetoceros spp. during CHAOS2‐neaps. About 50% of the primary production in the ecosystem during periods of upwelling relaxation‐stratification could be sustained by enhanced nitrate diffusive fluxes during spring tides. Therefore, even in coastal upwelling regions, turbulent mixing driven by internal waves could play an important role in controlling phytoplankton productivity and community structure.
A river‐scale Lagrangian experiment examining controls on phytoplankton dynamics in the presence and absence of treated wastewater effluent high in ammonium
Authors: Kraus Tamara E. C. , Carpenter Kurt D. , Bergamaschi Brian A. , Parker Alexander E. , Stumpner Elizabeth B. , Downing Bryan D. , Travis Nicole M. , Wilkerson Frances P. , Kendall Carol , Mussen Timothy D.
Published: February 2017

Phytoplankton are critical component of the food web in most large rivers and estuaries, and thus identifying dominant controls on phytoplankton abundance and species composition is important to scientists, managers, and policymakers. Recent studies from a variety of systems indicate that ammonium (
) in treated wastewater effluent decreases primary production and alters phytoplankton species composition. However, these findings are based mainly on laboratory and enclosure studies, which may not adequately represent natural systems. To test effects of effluent high in ammonium on phytoplankton at the ecosystem scale, we conducted whole‐river–scale experiments by halting discharges to the Sacramento River from the regional wastewater treatment plant (WWTP), and used a Lagrangian approach to compare changes in phytoplankton abundance and species composition in the presence (+EFF) and absence (−EFF) of effluent. Over 5 d of downstream travel from 20 km above to 50 km below the WWTP, chlorophyll concentrations declined from 15–25 to ∼2.5 μg L−1, irrespective of effluent addition. Benthic diatoms were dominant in most samples. We found no significant difference in phytoplankton abundance or species composition between +EFF and −EFF conditions. Moreover, greatest declines in chlorophyll occurred upstream of the WWTP where
concentrations were low. Grazing by clams and zooplankton could not account for observed losses, suggesting other factors such as hydrodynamics and light limitation were responsible for phytoplankton declines. These results highlight the advantages of conducting ecosystem‐scale, Lagrangian‐based experiments to understand the dynamic and complex interplay between physical, chemical, and biological factors that control phytoplankton populations.
Cardiovascular morbidity and mortality after liver transplantation: The protective role of mycophenolate mofetil
Authors: D'Avola Delia , Cuervas‐Mons Valentín , Martí Josep , Ortiz de Urbina Jorge , Lladó Laura , Jimenez Carlos , Otero Esteban , Suarez Francisco , Rodrigo Juan M. , Gómez Miguel‐Angel , Fraga Enrique , Lopez Pedro , Serrano M. Trinidad , Rios Antonio , Fábrega Emilio , Herrero José Ignacio
Published: February 2017

Cardiovascular (CV) diseases are recognized longterm causes of death after liver transplantation (LT). The objective of this multicenter study was to analyze the prevalence and the evolution of CV risk factors and CV morbidity and mortality in 1819 LT recipients along 5 years after LT. The influence of baseline variables on survival, morbidity, and mortality was studied. There was a continuous and significant increase of the prevalence of all the CV risk factors (except smoking) after LT. CV diseases were the fourth cause of mortality in the 5 years after LT, causing 12% of deaths during the follow‐up. Most CV events (39%) occurred in the first year after LT. Preexisting CV risk factors such as age, pre‐LT CV events, diabetes, metabolic syndrome, and hyperuricemia, and mycophenolate‐free immunosuppressive therapy, increased post‐LT CV morbidity and mortality. The development of new‐onset CV risk factors after LT, such as dyslipidemia and obesity, independently affected late CV morbidity and mortality. Tacrolimus and steroids increased the risk of posttransplant diabetes, whereas cyclosporine increased the risk of arterial hypertension, dyslipidemia, and metabolic syndrome. In conclusion, CV complications and CV mortality are frequent in LT recipients. Preexisting CV risk factors, immunosuppressive drugs, but also the early new onset of obesity and dyslipidemia after LT play an important role on late CV complications. A strict metabolic control in the immediate post‐LT period is advisable for improving CV risk of LT recipients. Liver Transplantation 23 498–509 2017 AASLD.
Recipient vessels for microsurgical flaps to the abdomen: A systematic review
Authors: Gurunluoglu Raffi , Rosen Michael J.
Published: February 2017

Background

Large soft tissue defects of the abdominal wall resulting from various reasons may require free tissue transfer.

Methods

A literature search of PubMed and Cochrane electronic databases was conducted to identify articles involving abdominal wall reconstruction (AWR) with microsurgical flap. Number of cases, etiology, and reconstruction site, type of microsurgical flap and recipient vessels were analyzed.

Results

Thirty‐eight articles published between 1983 and 2016 reported on 149 patients undergoing free flap AWR. TFL was used in 43 patients (28.8%), LAD in 43 (28.8%), and ALT in 28 (18.7%). Conjoined ALT and TFL flap was reported in 24 patients (16.1%). The inferior epigastric artery/vein were the most commonly utilized recipient vessels (n = 43 patients). Intraperitoneal vessels were used in 18 cases, the gastroepiploic vessels being the most common (n = 9). Femoral vessels were used directly or along with a vein graft in 14 patients. AV loop or vein graft was reported in 46 patients. Great saphenous vein rerouting was used in 8 cases. DLCF vessels were used in 2 patients to support an AV loop or directly the pedicle of a microsurgical flap. The internal thoracic vessels were used in only 3 patients.

Conclusions

The current review analyzed articles on AWR using microsurgical flaps with a special emphasis on the recipient vessels. The literature review demonstrated that there is no standard approach to repair a complex abdominal defect given the diversity of patient population. The choice of microsurgical flap and selection of recipient vessels should be tailored to the individual patient's circumstances.
Cover Image, Volume 66, Issue 3
Authors: Sparnacci Katia , Antonioli Diego , Perego Michele , Giammaria Tommaso Jacopo , Seguini Gabriele , Ferrarese Lupi Federico , Zuccheri Giampaolo , Gianotti Valentina , Laus Michele
Published: February 2017

The cover image, by Katia Sparnacci et al., is based on the Research Article High temperature surface neutralization process with random copolymers for block copolymer self‐assembly, DOI: 10.1002/pi.5285.

image
Enzymatic ring opening polymerization of ω‐Pentadecalactone in different solvents in a variable‐volume view reactor
Authors: Polloni André E. , Rebelatto Evertan A. , Veneral Josamaique G. , de Oliveira Débora , Oliveira J. Vladimir , Araújo Pedro H.H. , Sayer Claudia
Published: February 2017

The use of enzymes as catalyst in polyesters production enables the creation of new materials for use in biomedical applications. In this work, a polyester derived from ω‐pentadecalactone was synthesized. The polymer synthesis was performed using lipase Novozym 435 as catalyst and several solvents at 70 °C. The use of a closed variable volume reactor allowed the use of solvents with a boiling point lower than the reaction temperature, without affecting the ratio of solvent to monomer. Yields above 49 wt% and high molecular weights were obtained for all tested solvents. Dichloromethane (DCM) and chloroform were used as solvents for the evaluation of water content on enzyme and reaction time over the properties of final polymer. The amount of water on enzyme has a direct influence on reaction yields though higher molecular weights were obtained in reactions with lower water content. Yields of around 90 wt% were obtained in 6 h of reaction and molecular weights up to 42,300 and 51,900 g mol−1 were obtained in 2 h of reactions using DCM and chloroform as solvents. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 55, 1219–1227
Aqueous micro and nanoreactors based on alternating copolymers of phenylmaleimide and vinylpyrrolidone bearing pendant l‐proline stabilized with PEG grafted chains
Authors: del Prado Anselmo , Pintado‐Sierra Mercedes , Juan‐y‐Seva Marta , Navarro Rodrigo , Reinecke Helmut , Rodríguez‐Hernández Juan , Elvira Carlos , Fernández‐Mayoralas Alfonso , Gallardo Alberto
Published: February 2017

Proline may work efficiently in water as catalyst of aldol reactions if it is hydrophobically activated. In this work, we have maximized this hydrophobic activation by the preparation of linear alternating copolymers of hydrophobic phenylmaleimide and a vinylpyrrolidone derivative bearing proline. These copolymers were water soluble above pH 5.0 and, unlike the free proline, exhibited efficient catalysis at pH 7.0. Moreover, they catalyzed and presented enantioselectivity in an aggregated form at pH 4.0 (close to the isoelectric point, IEP, of the polymer). This enantioselectivity has been related to the exclusion of water at this IEP. To control the size and stabilize the aggregates, PEG grafted copolymers were prepared by the incorporation of a PEG‐macromer (2–10 mol%), which rendered stable nano‐aggregates in water at the IEP. At this pH they catalyzed the aldol reaction in a higher rate than the non‐grafted polymer, but the enantioselectivity was decreased. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 55, 1228–1236
Influence of topology on the gelation behavior of coordination polymers prepared via ROMP of macrocyclic olefins
Authors: Albano Simone , Fantozzi Alessio , Berrocal José Augusto , Di Stefano Stefano
Published: February 2017

This work reports on the consequences of concatenation of two twin macrocycles on the gelation behavior of coordination polymers obtained via ring‐opening metathesis polymerization (ROMP) initiated by 2nd generation Grubbs' catalyst. The influence of concatenation is evaluated by comparison with the behavior of a non‐interlocked model complex under the same reaction conditions. The suitability of the choice of the non‐interlocked model complex is discussed in terms of molecular structure and effective molarity (EM). It is found that concatenation has a primary role in the gelation process, resulting in lower critical gelation concentrations for the endotopic, interlocked complex compared with the exotopic, non‐interlocked one. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 55, 1237–1242
Chemistry of Hydrocarbons Under Extreme Thermobaric Conditions
Authors: Kolesnikov Anton Yu. , Saul John M. , Kutcherov Vladimir G.
Published: February 2017

What will happen when methane is at a temperature of 1500 K? On the first glance the answer seems to be obvious ‐ methane will decompose into hydrogen and one of the forms of carbon. Yes. However is does not do so at very high pressure, when novel reaction pathways become possible. The latest experimental results and theoretical calculations show that methane and heavier hydrocarbons are, remarkably enough, stable under extreme pressures and temperatures. Even more, experiments confirm the possibility of abiogenic synthesis of natural gas at 5.0 GPa and 1500 K. The review summarizes published results of theoretical and experimental investigations of possible pathways under the conditions of pressure and temperature that prevail in the Earth's upper mantle for the formation of (1) particular species of hydrocarbon molecules, and of (2) complex hydrocarbon systems. The results raise fundamental questions on the genesis of hydrocarbons.
Lipid Matrices Destabilization Induced by Some Newly Synthesized Pyridinium Salts
Authors: Luchese Angélica M. , Di Vitta Cláudio , Marzorati Liliana , Yamaoka Patrícia , Funari Sérgio S.
Published: February 2017

The influence of some newly synthesized pyridinium salts on the structural behavior of two lipid matrices formed with POPC or POPE was investigated by using SAXD. The structural impact / evolution of temperature scans were determined on samples prepared with different pyridinium salts / lipid helper molar ratio compositions, in water. In POPC based samples most complexes showed a strong sensitivity to the presence of pyridinium salts, mostly destructive of the long range order. A clear dependence of the structural behavior was correlated with pyridinium salt concentration. In POPE based samples the conformation of the hydrophobic part of such pyridinium salts seems to have a significant impact on the overall matrix structural behavior.
Mesoporous Quaternary Ce‐Ni‐Mn–Co Oxides as Electrodematerials forHighPerformance Flexible Solid‐StateAsymmetric Supercapacitors
Authors: Cheng Cheng , Wang Yan , Guo Ningning , Chang Jingjing , Du Weimin , Zhao Jianbo , Wei Chengzhen
Published: February 2017

Mesoporous quaternary Ce‐Ni‐Mn‐Co oxides microspheres have been successfully prepared by a solvothermal approach and subsequent heat treatment in air.As‐prepared mesoporous quaternary Ce‐Ni‐Mn‐Co oxides microspheres show a large specific surface areas of 146.1 m2 g‐1. When evaluated as an electrode of supercapacitors, the Ce‐Ni‐Mn‐Co oxides microspheres presents an outstanding specific capacitance of 1840.6 F g‐1 at 1.0 A g‐1. Furthermore, a flexible solid‐state asymmetric supercapacitor based on Ce‐Ni‐Mn‐Co oxides was also assembled, which possessed a highenergy density of 0.43 mW h cm‐3 and good electrochemical stability for 5000 cycles charge‐discharge measurement.Encouragingly, the flexible solid‐state electrochemical energy storage device shows well mechanical flexibility under various bending angles. The excellent electrochemical performances indicate the mesoporous quaternary Ce‐Ni‐Mn‐Co oxides microspheres are promising electrode materials in the energy storage.
Coumarin‐Rhodamine Hybrids – Synthesis, Photophysical Properties, NLO Properties and DFT Studies
Authors: Shreykar Milind R. , Sekar Nagaiyan
Published: February 2017

Solvatochromic and solvatofluoric behaviour of three coumarin rhodamine hybrid dyes (Cou‐Rhod1, Cou‐Rhod2 and Cou‐Rhod3) have been studied in ten different solvents with varying polarity. The pH (1‐10) study was done to investigate the spirocyclic ring opening. All the dyes show charge transfer phenomenon in local as well as charge transfer excitation. The non‐linear optical properties of coumarin rhodamine hybrid dyes were studied using solvatochromic method (highest value of αCT for Cou‐Rhod1=2.44 X 10−23; highest value of βCT for Cou‐Rhod2=0.14 X 10−28 and the highest value of γ for Cou‐Rhod2=0.02 X 10−34) and computational (highest value of α0 for Cou‐Rhod3=9.89 X 10−23; highest value of β0 for Cou‐Rhod1=0.90 X 10−28 and highest value of γ for Cou‐Rhod3=5.10 X 10−34) approach. As the non‐radiative rate constant increases quantum yield of the dyes decreases. Correlation of calculated radiative lifetime (τ), radiative (Kr) and non‐radiative rate constant (Knr) has been made to explain the quantum yield of dyes using Strickler‐Berg equation. The charge transfer behaviour, structural parameters and non‐linear optical properties of the dyes are well described by DFT and TD‐DFT calculations.
A Facile and Green Route for Conversion of Bifunctional Epoxide and Vegetable Oils to Cyclic Carbonate: A Green Route to CO2 Fixation
Authors: Farhadian Abdolreza , Gol Afshani Meisam Babapour , Babaei Miyardan Ahmad , Nabid Mohammad Reza , Safari Nasser
Published: February 2017

A porphyrin based catalytic system with three metals of Manganese, Zinc and Iron and quaternary ammonium salt as co‐catalyst showed very high selectivity for CO2 fixation reaction of different epoxide monomers for synthesizing cyclic carbonates. The reaction showed quantitative yields under solvent‐free and atmospheric pressure. Quaternary ammonium salts were able to catalyse these reactions singlehandedly, thus their mole ratios were decreased to investigate metalloporphyrins effect. After three cycles of reusing, this catalytic system showed minor reduction in activity and no weight loss. Also, manganese porphyrin has high ability to convert bifunctional epoxides (yield 98% in 4h) and vegetable oil by CO2 (yield 99% in 30h) to cyclic carbonates at ambient condition.
Prediction and Characterization of Alkaline‐Earth (M=Be, Mg, Ca, Sr, and Ba) Metallacyclopentadienes and Relevant Derivatives
Authors: Sun Zhi , Launder Andrew M. , Schaefer Henry F.
Published: February 2017

Alkaline‐earth metallacyclopentadienes are an active area of research in synthetic chemistry, notable for their roles as precursors of key cyclopentadiene derivatives. However, experimental characterization is limited due to their challenging synthesis and subsequent isolation. Herein, we report systematic theoretical studies of MC4H4 (M=Be, Mg, Ca, Sr, Ba) rings and experimentally relevant complexes. Benchmarking against CCSD(T) and experiment shows reasonable performance for the B3LYP, BP86, and M06‐2X density functionals in predicting the equilibrium geometries, thermochemistry, and vibrational spectra of these species. NICS indices and extra cyclic resonance energies confirm that the compounds in question possess antiaromatic character. For both the bare MC4H4 rings and larger complexes, the Be‐containing compounds were found to be the most strongly bound species. Such viability is explained via ring strain, electron densities, natural bond orders, and orbital analyses. Given that the second least viable Mg complex has been reported in recent experiments, synthesis and characterization of the other group IIA analogs are anticipated.
Microwave‐Assisted Valorization of Biowastes to Levulinic Acid
Authors: Tukacs József M. , Holló Ambrus T. , Rétfalvi Nóra , Cséfalvay Edit , Dibó Gábor , Havasi Dávid , Mika László T.
Published: February 2017

The valorization of cheap and readily available biomass‐based wastes such as various straws, husks, shells and peels, moreover, so far unprecedented, commercial and household wastes produced on large scale, i. e. spent coffee grounds and cooked tea leaves waste were processed as raw materials for the production of levulinic acid, a C5‐platform molecule. The results obtained by applying conventional and microwave dielectric heating at 170 °C were compared. It was revealed that depending on the source, the average product yields were 10–25 wt% when 2 M aqueous sulfuric acid solution was used. By applying microwave irradiation the reaction time can be significantly reduced (30 min instead of 8 h) without a decrease in product formation. The influence of the feedstock's water content on the formation of levulinic acid was investigated revealing that the drying process having significant energy needs can be eliminated from the procedure.
Facile Synthesis of 2,3‐Disubstituted Indoles by NBS/CuCl Mediated Oxidative Cyclization of N‐Aryl Enamines
Authors: Hu Fang‐Zhi , Zhao Si‐Han , Chen Hui , Yu Shuo‐Wen , Xu Xiao‐Ying , Yuan Wei‐Cheng , Zhang Xiao‐Mei
Published: February 2017

A one‐pot synthesis of 2,3‐disubstituted indoles has been accomplished through a facile, mild and efficient oxidative cyclization of N‐aryl enamines mediated by N‐bromosuccinimide (NBS)/copper chloride (CuCl). This method is applicable to a series of N‐aryl β‐enaminoesters and N‐aryl β‐amino nitroolefins containing different substituents such as halides, alkyls, heterocycles, etc. A variety of 2‐aryl‐3‐carboxylate indoles and 2‐aryl‐3‐nitro indoles have been prepared with moderate to quantitative yields in only 20 minutes to 2 hours in refluxing ethanol. Moreover, in order to demonstrate the synthetic utility of this transformation, 2‐phenyl‐3‐nitro indole was subjected in reduction and reduction‐alkylation to generate 2‐phenyl‐3‐amino indole and N,N‐diethyl‐2‐phenyl‐3‐amino indole respectively.
Hierarchical Porous O‐Doped g‐C3N4 with Enhanced Photocatalytic CO2 Reduction Activity
Authors: Fu Junwei , Zhu Bicheng , Jiang Chuanjia , Cheng Bei , You Wei , Yu Jiaguo
Published: February 2017

Artificial photosynthesis of hydrocarbon fuels by utilizing solar energy and CO2 is considered as a potential route for solving ever‐increasing energy crisis and greenhouse effect. Herein, hierarchical porous O‐doped graphitic carbon nitride (g‐C3N4) nanotubes (OCN‐Tube) are prepared via successive thermal oxidation exfoliation and curling‐condensation of bulk g‐C3N4. The as‐prepared OCN‐Tube exhibits hierarchically porous structures, which consist of interconnected multiwalled nanotubes with uniform diameters of 20–30 nm. The hierarchical OCN‐Tube shows excellent photocatalytic CO2 reduction performance under visible light, with methanol evolution rate of 0.88 µmol g−1 h−1, which is five times higher than bulk g‐C3N4 (0.17 µmol g−1 h−1). The enhanced photocatalytic activity of OCN‐Tube is ascribed to the hierarchical nanotube structure and O‐doping effect. The hierarchical nanotube structure endows OCN‐Tube with higher specific surface area, greater light utilization efficiency, and improved molecular diffusion kinetics, due to the more exposed active edges and multiple light reflection/scattering channels. The O‐doping optimizes the band structure of g‐C3N4, resulting in narrower bandgap, greater CO2 affinity, and uptake capacity as well as higher separation efficiency of photogenerated charge carriers. This work provides a novel strategy to design hierarchical g‐C3N4 nanostructures, which can be used as promising photocatalyst for solar energy conversion.
Lightning detection in planetary atmospheres
Authors: Aplin Karen L. , Fischer Georg
Published: February 2017

Lightning in planetary atmospheres is now a well‐established concept. Here we discuss the available detection techniques for, and observations of, planetary lightning by spacecraft, planetary landers and, increasingly, sophisticated terrestrial radio telescopes. Future space missions carrying lightning‐related instrumentation are also summarised, specifically the European ExoMars mission and Japanese Akatsuki mission to Venus, which could both yield lightning observations in 2016.
“They Just Want to Know” ‐ Genetic Health Professionals' Beliefs About Why Parents Want to Know their Child's Carrier Status
Authors: Vears Danya F. , Delany Clare , Massie John , Gillam Lynn
Published: February 2017

In the context of a child being diagnosed with a genetic condition, reports from both parents and health professionals suggest many genetic health professionals are reluctant to provide carrier testing for unaffected siblings, despite the lack of evidence of harm. We propose that genetic health professionals’ understandings of why parents want to have their children tested may contribute to their reluctance to test. We draw on interviews with 17 genetic health professionals, reporting their beliefs about parents’ motivations for testing and their intentions to communicate results to their children. Data were analyzed using inductive content analysis. Genetic health professionals reported attributions that contrasted with reasons parents actually report. These disparities fall into two categories: 1) attributing reasons that parents do not themselves report (i.e. for reassurance about their child's health), and 2) not recognizing the reasons that parents actually do report for wanting testing (i.e. to communicate the information to their child). By identifying that genetic health professionals may be misattributing reasons to parents for desiring their child”s carrier status, they may be missing an opportunity to assist parents to make decisions that are in line with their values and the best interests of the family.
Spatial pattern of soil nitrogen availability and its relationship to stand structure in a coniferous‐broadleaved mixed forest with a dense dwarf bamboo understory in northern Japan
Authors: Inoue Takahiro , Fukuzawa Karibu , Watanabe Tsunehiro , Yoshida Toshiya , Shibata Hideaki
Published: February 2017

Natural disturbances create spatial patterns of the ecosystem processes and functions in natural forests. However, how dynamics and the spatial structure of forests relate to soil nitrogen dynamics is not well understood. We examined the spatial relationship between the distributions of canopy and understory species, and soil nitrogen dynamics in a natural coniferous‐broadleaved mixed forest with a dense understory of Sasa dwarf bamboo in northern Japan. The O horizon was thick where coniferous litter predominated, and it was thin where broadleaved litter predominated. The soil water content was low in areas with a thick O horizon and a high abundance of coniferous trees. The soil nitrate content was low where the soil water content was low, and the soil nitrate content increased linearly with increasing net nitrification potential. These results suggest that the soil nitrate content under the coniferous canopy was lower because of the low nitrification potential of soil microbes in soils with low water contents. The soil nitrate content and nitrification potential were higher in the canopy gap than under the canopy. Our results suggest that forest structure, specifically the thickness of the forest floor, significantly affects the spatial pattern of the soil water content, thereby creating a spatial pattern of soil nitrogen availability at a relatively small scale with flat topography. The higher nitrification potential under the canopy gap could pose a long‐term risk of nitrate leaching because of the suppression of the natural regeneration of canopy species by dense Sasa dwarf bamboo in this forest ecosystem.
Associations between alcohol‐use and depression symptoms in adolescence: Examining gender differences and pathways over time
Authors: Danzo Sarah , Connell Arin M. , Stormshak Elizabeth A.
Published: February 2017

Several studies examining alcohol use and depression in youth have focused on documenting prevalence of overlap, or temporal ordering in longitudinal samples. Fewer studies have examined pathways connecting alcohol use and depression over time. This study examined gender differences between depression and alcohol use across adolescence while examining peer and family pathways as possible mediators of effects. Data was collected longitudinally from 593 families from three urban public middle schools in the United States. Participants were recruited in 6th grade and followed through 9th grade. We examined gender differences using a nested model comparison approach. Results indicated the association between depression and alcohol use differs by gender. For males, depression and alcohol use were independent across adolescence, and no significant indirect pathways were observed. For females, bidirectional effects were found between alcohol use and depression, as well as an indirect effect from depression to alcohol use via peer deviance.
Colovesical fistula secondary to hernia mesh migration: an unusual incident
Authors: Ramanathan Sabarinathan , Krishnamoorthy Veeraraghavan , Ratnakar Kini , Thangavel Pugazhendhi , Sundarraj Raju
Published: February 2017

We evaluated a 27-year old male with pneumaturia and fecaluria with a past history of right inguinal hernia repair. Though, cystoscopy and contrast enhanced computed tomography did not furnish any evidence to arrive at a diagnosis, interestingly, colonoscopy revealed a mesh in the sigmoid colon making apparent the diagnosis of colovesical fistula secondary to mesh migration. Later, surgical removal of the mesh from the sigmoid colon with rent closure of the fistulous opening was done successfully. Our case thus, highlights the vital role of common diagnostic tool like colonoscopy in making an uncommon diagnosis.
High‐resolution mapping and ablation of recurrent left lateral accessory pathway conduction
Authors: Solimene Francesco , Schillaci Vincenzo , Shopova Gergana , Maddaluno Francesco , Malacrida Maurizio , Stabile Giuseppe
Published: February 2017

Proper localization of the anatomical target during ablation of the accessory pathways (AP) and the ability to detect clear AP potentials on the ablation catheter are crucial for successful AP ablation. We report a case of recurring AP conduction that was finally eliminated using a novel ablation catheter equipped with high‐resolution mini‐electrodes. Smaller and closer electrodes result in high mapping resolution with less signal averaging and cancellation effects. Owing to improved sensitivity, the new catheter seems effective in detecting fragmented and high frequency signals, thus allowing more effective radiofrequency application and improving ablation success.