bluuebunny/crossref_metadata_2025 huggingface dataset:
Asymmetric Cation‐Binding Catalysis
Authors: Oliveira Maria Teresa , Lee Ji‐Woong
Published: December 2016

The employment of metal salts is quite limited in asymmetric catalysis, although it would provide an additional arsenal of safe and inexpensive reagents to create molecular functions with high optical purity. Cation chelation by polyethers increases the salts’ solubility in conventional organic solvents, thus increasing their applicability in synthesis. The expansion of this concept to chiral polyethers led to the emergence of asymmetric cation‐binding catalysis, where chiral counter anions are generated from metal salts, particularly using BINOL‐based polyethers. Alkali metal salts, namely KF and KCN, are selectively bound to the catalyst, providing exceptionally high enantioselectivities for kinetic resolutions, elimination reactions (fluoride base), and Strecker synthesis (cyanide nucleophile). Asymmetric cation‐binding catalysis was recently expanded to silicon‐based reagents, enabling highly enantioselective silylation reactions in polyether‐generated chiral environments, and leading to a record‐high turnover in asymmetric organocatalysis. This can lead to further applications by the asymmetric use of other inorganic salts in various organic transformations.
Electrocatalytic Activity and Stability Enhancement through Preferential Deposition of Phosphide on Carbide
Authors: Regmi Yagya N. , Roy Asa , Goenaga Gabriel A. , McBride James R. , Rogers Bridget. R. , Zawodzinski Thomas A. , Labbé Nicole , Chmely Stephen C.
Published: December 2016

Phosphides and carbides are among the most promising families of materials based on earth‐abundant elements for renewable energy conversion and storage technologies such as electrochemical water splitting, batteries, and capacitors. Nickel phosphide and molybdenum carbide in particular have been extensively investigated for electrochemical water splitting. However, a composite of the two compounds has not been explored. Here, we demonstrate preferential deposition of nickel phosphide on molybdenum carbide in the presence of carbon by using a hydrothermal synthesis method. We employ the hydrogen evolution reaction in acid and base to analyze the catalytic activity of phosphide‐deposited carbide. The composite material also shows superior electrochemical stability in comparison to unsupported phosphide. We anticipate that the enhanced electrochemical activity and stability of carbide deposited with phosphide will stimulate investigations into the preparation of other carbide–phosphide composite materials.
Variable clustering and spectral angle mapper‐orthogonal projection method for Raman mapping of compound detection in tablets
Authors: Farkas Attila , Nagy Brigitta , Démuth Balázs , Balogh Attila , Pataki Hajnalka , Nagy Zsombor K. , Marosi György
Published: December 2016

Raman mapping and chemometrics are proposed to accurately characterize the composition of tablets. The most critical step of the state‐of‐art curve resolution methods (such as multivariate curve resolution‐alternating least squares [MCR‐ALS]) is the determination of the number of constituents, when chemical imaging is coupled with multivariate data analysis. However, it is usually performed in a considerably subjective way. We propose a variable clustering approach for the identification of the main dimensionality of vibrational spectral data. The method was tested on a Raman map of a complex pharmaceutical tablet that contained 4 major components with high spectral resemblance, and a low‐dose lubricant was also added for tableting purposes. Using a variable clustering algorithm called VARCLUS we were able to construct clusters from the Raman mapping data corresponding to the real constitution of the sample. The modeled clusters were analyzed by the “sum of ranking differences” method. All 4 major components could be identified. The potential of the clustering algorithm was further assessed by applying MCR‐ALS and spectral angle mapper‐orthogonal projection methods. We have shown that variable clustering corresponded with MCR‐ALS results and that it can be used to characterize the qualitative composition of an unknown pharmaceutical sample by combining the clustering algorithm with a pure component resolution method. Therefore, this method is well applicable to analyze and interpret the curve resolution of complex samples. Testing of the previously studied spectral angle mapper‐orthogonal projection method, which relies on spectral reference libraries and even the low‐dose lubricant (approximately 1% w/w), was identified through the chemical imaging.
Csp3−H Activation without Chelation Assistance in an Iridium Pincer Complex Forming Cyclometallated Products
Authors: Ahlstrand David A. , Polukeev Alexey V. , Marcos Rocío , Ahlquist Mårten S. G. , Wendt Ola F.
Published: December 2016

Cyclometallation of 8‐methylquinoline and 2‐(dimethylamino)‐pyridine in an iridium‐based pincer complex is described. The C−H activation of 2‐(dimethylamino)pyridine is not chelation assisted, which has not been described before for Csp3−H bonds in cyclometallation reactions. The mechanism of the cyclometallation of 2‐(dimethylamino)pyridine was studied by DFT calculations and kinetic measurements.
New Conjugated meso‐Tetrafluorenylporphyrin‐Cored Derivatives as Fluorescent Two‐Photon Photosensitizers for Singlet Oxygen Generation
Authors: Yao Dandan , Zhang Xu , Triadon Amédée , Richy Nicolas , Mongin Olivier , Blanchard‐Desce Mireille , Paul Frédéric , Paul‐Roth Christine O.
Published: December 2016

A series of three conjugated meso‐porphyrin dendrimers containing conjugated dendrons featuring 2,7‐fluorenyl groups, incorporating overall 8, 12, or 28 fluorenyl units have been synthesized and characterized. The photophysical properties of these new compounds were studied in the context of photodynamic therapy. The relevant linear and nonlinear optical properties were measured in organic media and useful structure–properties relationships were derived.
Crystal Structure of the DFNKF Segment of Human Calcitonin Unveils Aromatic Interactions between Phenylalanines
Authors: Bertolani Arianna , Pizzi Andrea , Pirrie Lisa , Gazzera Lara , Morra Giulia , Meli Massimiliano , Colombo Giorgio , Genoni Alessandro , Cavallo Gabriella , Terraneo Giancarlo , Metrangolo Pierangelo
Published: December 2016

Invited for the cover of this issue is the group of Pierangelo Metrangolo at the Politecnico di Milano. The image depicts the steric zipper formed by the amyloidogenic peptide, DFNKF. Read the full text of the article at 10.1002/chem.201604639.
Functionalization of Hydrogenated Chemical Vapour Deposition‐Grown Graphene by On‐Surface Chemical Reactions
Authors: Drogowska Karolina , Kovaříček Petr , Kalbáč Martin
Published: December 2016

The reactivity of hydrogenated graphene when treated with oxidising agents, KMnO4 and KIO4, as well as alkylated with benzyl bromide (BnBr) was studied. The probed reactions are strictly limited to the partly hydrogenated form of graphene in which most of the hydrogen atoms are located in activated benzylic/allylic positions. This, in turn, clearly demonstrates the presence of hydrogen attached to the graphene lattice. Attachment of the benzyl group was also unequivocally demonstrated by characteristic vibrations recorded in the surface‐enhanced Raman spectra, and all reactions were shown to proceed solely on hydrogenated graphene as evidenced by the comparison with pristine chemical vapour deposition‐grown graphene.
Zuverlässigkeit in der Nanosicherheitsforschung
Authors: Krug Harald Friedrich , Nau Katja
Published: December 2016

Auch nach 15 Jahren intensiver Risikoforschung zu Nanomaterialien gestaltet sich die Beurteilung einzelner Materialien noch schwierig. Je länger geforscht wird, umso mehr Studien werden publiziert, die kritische Effekte der Nanomaterialien beobachten. Dabei sollte aber beachtet werden, dass die meisten Studien keine verwertbaren toxikologischen Inhalte haben, auch wenn sie vielfach als solche zitiert und von der Tagespresse aufgegriffen werden. Es mangelt an Verlässlichkeit in der wissenschaftlichen Praxis, insb. in der Nanosicherheitsforschung. Hier wird diese Aussage anhand von Beispielen belegt und Lösungsvorschläge werden aufgezeigt.
Recommendations for the standardization of bone marrow disease assessment and reporting in children with neuroblastoma on behalf of the International Neuroblastoma Response Criteria Bone Marrow Working Group
Authors: Burchill Susan A. , Beiske Klaus , Shimada Hiroyuki , Ambros Peter F. , Seeger Robert , Tytgat Godelieve A.M. , Brock Penelope R. , Haber Michelle , Park Julie R. , Berthold Frank
Published: December 2016

BACKGROUND

The current study was conducted to expedite international standardized reporting of bone marrow disease in children with neuroblastoma and to improve equivalence of care.

METHODS

A multidisciplinary International Neuroblastoma Response Criteria Bone Marrow Working Group was convened by the US National Cancer Institute in January 2012 with representation from Europe, North America, and Australia. Practical transferable recommendations to standardize the reporting of bone marrow disease were developed.

RESULTS

To the authors' knowledge, the current study is the first to comprehensively present consensus criteria for the collection, analysis, and reporting of the percentage area of bone marrow parenchyma occupied by tumor cells in trephine‐biopsies. The quantitative analysis of neuroblastoma content in bone marrow aspirates by immunocytology and reverse transcriptase‐quantitative polymerase chain reaction are revised. The inclusion of paired‐like homeobox 2b (PHOX2B) for immunohistochemistry and reverse transcriptase‐quantitative polymerase chain reaction is recommended. Recommendations for recording bone marrow response are provided. The authors endorse the quantitative assessment of neuroblastoma cell content in bilateral core needle biopsies‐trephines and aspirates in all children with neuroblastoma, with the exception of infants, in whom the evaluation of aspirates alone is advised. It is interesting to note that 5% disease is accepted as an internationally achievable level for disease assessment.

CONCLUSIONS

The quantitative assessment of neuroblastoma cells is recommended to provide data from which evidence‐based numerical criteria for the reporting of bone marrow response can be realized. This is particularly important in the minimal disease setting and when neuroblastoma detection in bone marrow is intermittent, where clinical impact has yet to be validated. The wide adoption of these harmonized criteria will enhance the ability to compare outcomes from different trials and facilitate collaborative trial design. Cancer 2017;123:1095–1105. © 2016 American Cancer Society.
No impact of breast magnetic resonance imaging on 15‐year outcomes in patients with ductal carcinoma in situ or early‐stage invasive breast cancer managed with breast conservation therapy
Authors: Vapiwala Neha , Hwang Wei‐Ting , Kushner Carolyn J. , Schnall Mitchell D. , Freedman Gary M. , Solin Lawrence J.
Published: December 2016

BACKGROUND

For women undergoing breast conservation therapy (BCT), the added value of breast magnetic resonance imaging (MRI) at the time of initial diagnosis remains controversial. The current study was performed to determine long‐term outcomes after BCT for women with and without pretreatment breast MRI.

METHODS

Between 1992 and 2001, a total of 755 women with ductal carcinoma in situ or early‐stage invasive breast cancer underwent breast‐conserving surgery (with axillary lymph node staging for invasive carcinoma) followed by definitive breast radiotherapy. Evaluation at the time of the initial diagnosis included conventional mammography in all subjects and breast MRI in 215 women (28%). Clinical, pathologic, and treatment characteristics were comparable for patients with and without breast MRI. Outcomes were determined using the Kaplan‐Meier method and compared using the log‐rank method.

RESULTS

At a median follow‐up of 13.8 years, there were 49 local failures (15 women with and 34 women without breast MRI, respectively). The 15‐year local failure rates were 8% for women with and 8% for women without MRI (P = .59). There also were no differences noted between women with and without breast MRI with regard to 15‐year rates of overall survival (77% vs 71%;P = .24), freedom from distant metastases (86% vs 90%;P = .08), and contralateral breast cancer (10% vs 8%;P = .10). Multivariate analysis demonstrated no significant impact of breast MRI on local failure (P = .96).

CONCLUSIONS

Breast MRI during the initial evaluation for BCT appears to have no significant impact on 15‐year rates for local control, overall survival, freedom from distant metastases, or contralateral breast cancer. The routine use of pretreatment breast MRI is not indicated for patients undergoing BCT.Cancer2017;123:1324–1332.©2016 American Cancer Society.
Lipidic Cubic‐Phase Nanoparticles—Cubosomes for Efficient Drug Delivery to Cancer Cells
Authors: Nazaruk Ewa , Majkowska‐Pilip Agnieszka , Bilewicz Renata
Published: December 2016

Self‐assembled lipid liquid‐crystalline nanoparticles, known as cubosomes, were used for the delivery of the anticancer drug doxorubicin (DOX). Several properties make cubosomes a promising alternative in the development of controlled‐release systems for drug delivery. They have a larger internal surface area than other carriers, hence deliver more drug molecules to the affected cells and maintain the cubic symmetry of the parent lipidic cubic phase, but at the same time they have a lower viscosity thereby facilitating transport of the drug. The pH‐dependent drug release profiles, evaluated by voltammetry, demonstrated triggered drug release from the cubosome carrier to the environment of the cancer cells, where pH is lower. The anticancer effect of a DOX‐loaded cubosome on the glioblastoma T98G cell line was found to be highly efficient and required lower concentrations of DOX to inhibit the proliferation of cancer cells than the effective concentrations of free DOX.
Pharmacogenetic Implementation Lessons From the “Real World”
Authors: Roden DM
Published: December 2016

The manuscript “Anticoagulation Endpoints With Clinical Implementation of Warfarin Pharmacogenetic Dosing in a Real‐ World Setting: A Proposal for a New Pharmacogenetic Dosing Approach” describes process outcomes in an institutional program to use pharmacogenetic testing to optimize warfarin dose in a cohort of 257 patients of diverse ancestries. The strengths and weaknesses of the approach and program are discussed, along with the current and potential future status of warfarin as a model for pharmacogenetic testing.
Clinical Pharmacokinetics and Pharmacodynamics of Atezolizumab in Metastatic Urothelial Carcinoma
Authors: Stroh M , Winter H , Marchand M , Claret L , Eppler S , Ruppel J , Abidoye O , Teng SL , Lin WT , Dayog S , Bruno R , Jin J , Girish S
Published: December 2016

Atezolizumab, a humanized immunoglobulin G1 (IgG1) monoclonal antibody targeting human programmed death‐ligand 1 (PD‐L1), is US Food and Drug Administration (FDA) approved in metastatic urothelial carcinoma (MUC) and is being investigated in various malignancies. This analysis based upon 906 patients from two phase I and one phase II MUC studies, is the first report of the clinical pharmacokinetics (PK) and pharmacodynamics (PD) of atezolizumab. Atezolizumab exhibited linear PK over a dose range of 1–20 mg/kg, including the labeled 1,200 mg dose. The clearance, volume of distribution, and terminal half‐life estimates from population pharmacokinetic (PopPK) analysis of 0.200 L/day, 6.91 L, and 27 days, respectively, were as expected for an IgG1. Exposure‐response analyses did not identify statistically significant relationships with either objective response rate or adverse events of grades 3–5 or of special interest. None of the statistically significant covariates from PopPK (body weight, gender, antitherapeutic antibody, albumin, and tumor burden) would require dose adjustment.
Resource allocation in heterogeneous cooperative cognitive radio networks
Authors: Awoyemi Babatunde S. , Maharaj Bodhaswar T. , Alfa Attahiru S.
Published: December 2016

In cognitive radio networks (CRNs), resources available for use are usually very limited. This is generally because of the tight constraints by which the CRN operate. Of all the constraints, the most critical one is the level of permissible interference to the primary users. Attempts to mitigate the limiting effects of this constraint, thus achieving higher productivity, are a current research focus, and in this work cooperative diversity is investigated as a promising solution. Cooperative diversity has the capability to achieve diversity gain for wireless networks. In the work, therefore, the possibility of and mechanism for achieving greater utility for the CRN when cooperative diversity is incorporated are studied. To accomplish this, a resource allocation model is developed and analyzed for the heterogeneous, cooperative CRN. In the model, during cooperation, a best relay is selected to assist the secondary users that have poor channel conditions. Overall, the cooperation makes it feasible for virtually all the secondary users to improve their transmission rates while still causing minimal harm to the primary users. The results show a marked improvement in the resource allocation performance of the CRN when cooperation is used in contrast to when the CRN operates only by direct communication.
The Antinociceptive Effect of a Tapentadol‐Ketorolac Combination in a Mouse Model of Trigeminal Pain is Mediated by Opioid Receptors and ATP‐Sensitive K+ Channels
Authors: Barreras‐Espinoza Israel , Soto‐Zambrano José Alberto , Serafín‐Higuera Nicolás , Zapata‐Morales Ramón , Alonso‐Castro Ángel , Bologna‐Molina Ronell , Granados‐Soto Vinicio , Isiordia‐Espinoza Mario A.
Published: December 2016

Preclinical Research

The aim of the present study was to evaluate the antinoceptive interaction between the opioid analgesic, tapentadol, and the NSAID, ketorolac, in the mouse orofacial formalin test. Tapentadol or ketorolac were administered ip 15 min before orofacial formalin injection. The effect of the individual drugs was used to calculate their ED50 values and different proportions (tapentadol‐ketorolac in 1:1, 3:1, and 1:3) were assayed in the orofacial test using isobolographic analysis and interaction index to evaluate the interaction between the drugs. The combination showed antinociceptive synergistic and additive effects in the first and second phase of the orofacial formalin test. Naloxone and glibenclamide were used to evaluate the possible mechanisms of action and both partially reversed the antinociception produced by the tapentadol‐ketorolac combination. These data suggest that the mixture of tapentadol and ketorolac produces additive or synergistic interactions via opioid receptors and ATP‐sensitive K+ channels in the orofacial formalin‐induced nociception model in mice. Drug Dev Res 78 : 63–70, 2017. © 2016 Wiley Periodicals, Inc.
Neural mechanisms of attention become more specialised during infancy: Insights from combined eye tracking and EEG
Authors: Kulke Louisa , Atkinson Janette , Braddick Oliver
Published: December 2016

The Fixation Shift Paradigm (FSP) measures infants’ ability to shift gaze from a central fixation stimulus to a peripheral target (e.g. Hood & Atkinson, 1993: Infant Behavior and Development, 16(4), 405–422). Cortical maturation has been suggested as crucial for the developing ability to shift attention. This study investigated the development of neural mechanisms by combining EEG with simultaneous eye tracking during FSP testing, in typically developing infants aged between 1 and 8 months. The most prominent neural response was a frontal positivity which occurred only in the hemisphere contralateral to the target in the youngest infants but became more ipsilateral with age. This changing lateralisation was associated with improving ability to shift attention (decreasing saccade latencies and fewer ‘sticky fixations’—failures to disengage attention from the central target). These findings suggest that the lateralisation of neural responses develops during infancy, possibly due to developing intracortical connections, allowing infants to shift attention more efficiently.

RESEARCH HIGHLIGHTS

Successful use of combined simultaneous remote eye tracking and EEG to measure infant attention shifts.

Neural responses involved in attention shifts change in the first year of life.

The lateralisation of EEG responses changes with age in the first year of life.

Frontal cortex is involved in attention shifts from around 2 months of age.
Assessing the ecosystem‐level consequences of a small‐scale artisanal kelp fishery within the context of climate‐change
Authors: Krumhansl Kira A. , Bergman Jordanna N. , Salomon Anne K.
Published: December 2016

Coastal communities worldwide rely on small‐scale artisanal fisheries as a means of increasing food security and alleviating poverty. Even small‐scale fishing activities, however, are prone to resource depletion and environmental degradation, which can erode livelihoods in the long run. Thus, there is a pressing need to identify viable and resilient artisanal fisheries, and generate knowledge to support management within the context of a rapidly changing climate. We examined the ecosystem‐level consequences of an artisanal kelp fishery (Macrocystis pyrifera), finding small‐scale harvest of this highly productive species poses minimal impacts on kelp recovery rates, survival, and biomass dynamics, and abundances of associated commercial and culturally important fish species. These results suggest that small‐scale harvest poses minimal trade‐offs for the other economic benefits provided by these ecosystems, and their inherent, spiritual, and cultural value to humans. However, we detected a negative impact of warmer seawater temperatures on kelp recovery rates following harvest, indicating that the viability of harvest, even at small scales, may be threatened by future increases in global ocean temperature. This suggests that negative impacts of artisanal fisheries may be more likely to arise in the context of a warming climate, further highlighting the widespread effects of global climate change on coastal fisheries and livelihoods.
Disordered eating in ethnic minority adolescents with overweight
Authors: Rodgers Rachel F. , Watts Allison W. , Austin S. Bryn , Haines Jess , Neumark‐Sztainer Dianne
Published: December 2016

High rates of disordered eating exist among adolescents with overweight and among ethnic/racial minority adolescents. Given the lack of research examining how eating disorder risk is moderated by both overweight and ethnicity/race, this study aimed to explore interactions between ethnicity/race and overweight status on disordered eating behaviors in a population‐based adolescent sample.

Cross‐sectional data from adolescents (n = 2,271; 52% females) of White (23%), Black (34%), Hispanic (20%), and Asian (23%; 82% Hmong) ethnicity/race participating in the EAT 2010 study were used to examine associations between overweight status and disordered eating behaviors across ethnic/racial groups.

Disordered eating behaviors occurred more frequently among adolescents with overweight compared with those without overweight across all ethnic/racial groups. Although some differences in the prevalence of disordered eating were found by ethnicity/race, particularly in girls, no consistent patterns of interaction emerged. Overweight White and Hispanic girls reported the highest risk for dieting, while the highest risk for unhealthy weight control behaviors was among overweight Black girls, and for overeating among overweight White and Asian girls.

Within a society in which thinness is highly valued and being overweight is stigmatized, across diverse cultural groups, adolescents with overweight are at risk for disordered eating.
Spatial and temporal avoidance of risk within a large carnivore guild
Authors: Dröge Egil , Creel Scott , Becker Matthew S. , M'soka Jassiel
Published: December 2016

Within a large carnivore guild, subordinate competitors (African wild dog,Lycaon pictus, and cheetah,Acinonyx jubatus) might reduce the limiting effects of dominant competitors (lion,Panthera leo, and spotted hyena,Crocuta crocuta) by avoiding them in space, in time, or through patterns of prey selection. Understanding how these competitors cope with one other can inform strategies for their conservation. We tested how mechanisms of niche partitioning promote coexistence by quantifying patterns of prey selection and the use of space and time by all members of the large carnivore guild within Liuwa Plain National Park in western Zambia. Lions and hyenas specialized on wildebeest, whereas wild dogs and cheetahs selected broader diets including smaller and less abundant prey. Spatially, cheetahs showed no detectable avoidance of areas heavily used by dominant competitors, but wild dogs avoided areas heavily used by lions. Temporally, the proportion of kills by lions and hyenas did not detectably differ across four time periods (day, crepuscular, early night, and late night), but wild dogs and especially cheetahs concentrated on time windows that avoided nighttime hunting by lions and hyenas. Our results provide new insight into the conditions under which partitioning may not allow for coexistence for one subordinate species, the African wild dog, while it does for cheetah. Because of differences in responses to dominant competitors, African wild dogs may be more prone to competitive exclusion (local extirpation), particularly in open, uniform ecosystems with simple (often wildebeest dominated) prey communities, where spatial avoidance is difficult.
The effects of catchment and riparian forest quality on stream environmental conditions across a tropical rainforest and oil palm landscape in Malaysian Borneo
Authors: Luke Sarah H. , Barclay Holly , Bidin Kawi , Chey Vun Khen , Ewers Robert M. , Foster William A. , Nainar Anand , Pfeifer Marion , Reynolds Glen , Turner Edgar C. , Walsh Rory P. D. , Aldridge David C.
Published: December 2016

Freshwaters provide valuable habitat and important ecosystem services but are threatened worldwide by habitat loss and degradation. In Southeast Asia, rainforest streams are particularly threatened by logging and conversion to oil palm, but we lack information on the impacts of this on freshwater environmental conditions, and the relative importance of catchment versus riparian‐scale disturbance. We studied 16 streams in Sabah, Borneo, including old‐growth forest, logged forest, and oil palm sites. We assessed forest quality in riparian zones and across the whole catchment and compared it with stream environmental conditions including water quality, structural complexity, and organic inputs. We found that streams with the highest riparian forest quality were nearly 4 °C cooler, over 20 cm deeper, had over 40% less sand, greater canopy cover, more stored leaf litter, and wider channels than oil palm streams with the lowest riparian forest quality. Other variables were significantly related to catchment‐scale forest quality, with streams in the highest quality forest catchments having 40% more bedrock and 20 times more dead wood, along with higher phosphorus, and lower nitrate‐N levels compared to streams with the lowest catchment‐scale forest quality. Although riparian buffer strips went some way to protecting waterways, they did not maintain fully forest‐like stream conditions. In addition, logged forest streams still showed signs of disturbance 10–15 years after selective logging. Our results suggest that maintenance and restoration of buffer strips can help to protect healthy freshwater ecosystems but logging practices and catchment‐scale forest management also need to be considered.
Long‐term structural and biomass dynamics of virgin Tsuga canadensis–Pinus strobus forests after hurricane disturbance
Authors: D'Amato Anthony W. , Orwig David A. , Foster David R. , Barker Plotkin Audrey , Schoonmaker Peter K. , Wagner Maggie R.
Published: December 2016

The development of old‐growth forests in northeastern North America has largely been within the context of gap‐scale disturbances given the rarity of stand‐replacing disturbances. Using the 10‐ha old‐growth Harvard Tract and its associated 90‐year history of measurements, including detailed surveys in 1989 and 2009, we document the long‐term structural and biomass development of an old‐growth Tsuga canadensis–Pinus strobus forest in southern New Hampshire, USA following a stand‐replacing hurricane in 1938. Measurements of aboveground biomass pools were integrated with data from second‐ and old‐growth T. canadensis forests to evaluate long‐term patterns in biomass development following this disturbance. Ecosystem structure across the Tract prior to the hurricane exhibited a high degree of spatial heterogeneity with the greatest levels of live tree basal area (70–129 m2/ha) on upper west‐facing slopes where P. strobus was dominant and intermixed with T. canadensis. Live‐tree biomass estimates for these stratified mixtures ranged from 159 to 503 Mg/ha at the localized, plot scale (100 m2) and averaged 367 Mg/ha across these portions of the landscape approaching the upper bounds for eastern forests. Live‐tree biomass 71 years after the hurricane is more uniform and lower in magnitude, with T. canadensis currently the dominant overstory tree species throughout much of the landscape. Despite only one living P. strobus stem in the 2009 plots (and fewer than five stems known across the entire 10‐ha area), the detrital legacy of this species is pronounced with localized accumulations of coarse woody debris exceeding 237.7–404.2 m3/ha where this species once dominated the canopy. These patterns underscore the great sizes P. strobus attained in pre‐European landscapes and its great decay resistance relative to its forest associates. Total aboveground biomass pools in this 71‐year‐old forest (255 Mg/ha) are comparable to those in modern old‐growth ecosystems in the region that also lack abundant white pine. Results highlight the importance of disturbance legacies in affecting forest structural conditions over extended periods following stand‐replacing events and underscore that post‐disturbance salvage logging can alter ecosystem development for decades. Moreover, the dominant role of old‐growth P. strobus in live and detrital biomass pools before and after the hurricane, respectively, demonstrate the disproportionate influence this species likely had on carbon storage at localized scales prior to the widespread, selective harvesting of large P. strobus across the region in the 18th and 19th centuries.
Sources of variation in foliar secondary chemistry in a tropical forest tree community
Authors: Sedio Brian E. , Rojas Echeverri Juan C. , Boya P. Cristopher A. , Wright S. Joseph
Published: December 2016

Specialist herbivores and pathogens could induce negative conspecific density dependence among their hosts and thereby contribute to the diversity of plant communities. A small number of hyperdiverse genera comprise a large portion of tree diversity in tropical forests. These closely related congeners are likely to share natural enemies. Diverse defenses could still allow congeners to partition niche space defined by natural enemies, but interspecific differences in defenses would have to exceed intraspecific variation in defenses. We ask whether interspecific variation in secondary chemistry exceeds intraspecific variation for species from four hyperdiverse tropical tree genera. We used novel methods to quantify chemical structural similarity for all compounds present in methanol extracts of leaf tissue. We sought to maximize intraspecific variation by selecting conspecific leaves from different ontogenetic stages (expanding immature vs. fully hardened mature), different light environments (deep understory shade vs. large forest gaps), and different seasons (dry vs. wet). Chemical structural similarity differed with ontogeny, light environment, and season, but interspecific differences including those among congeneric species were much larger. Our results suggest that species differences in secondary chemistry are large relative to within‐species variation, perhaps sufficiently large to permit niche segregation among congeneric tree species based on chemical defenses.
Coastal regime shifts: rapid responses of coastal wetlands to changes in mangrove cover
Authors: Guo Hongyu , Weaver Carolyn , Charles Sean P. , Whitt Ashley , Dastidar Sayantani , D'Odorico Paolo , Fuentes Jose D. , Kominoski John S. , Armitage Anna R. , Pennings Steven C.
Published: December 2016

Global changes are causing broad‐scale shifts in vegetation communities worldwide, including coastal habitats where the borders between mangroves and salt marsh are in flux. Coastal habitats provide numerous ecosystem services of high economic value, but the consequences of variation in mangrove cover are poorly known. We experimentally manipulated mangrove cover in large plots to test a set of linked hypotheses regarding the effects of changes in mangrove cover. We found that changes in mangrove cover had strong effects on microclimate, plant community, sediment accretion, soil organic content, and bird abundance within 2 yr. At higher mangrove cover, wind speed declined and light interception by vegetation increased. Air and soil temperatures had hump‐shaped relationships with mangrove cover. The cover of salt marsh plants decreased at higher mangrove cover. Wrack cover, the distance that wrack was distributed from the water's edge, and sediment accretion decreased at higher mangrove cover. Soil organic content increased with mangrove cover. Wading bird abundance decreased at higher mangrove cover. Many of these relationships were non‐linear, with the greatest effects when mangrove cover varied from zero to intermediate values, and lesser effects when mangrove cover varied from intermediate to high values. Temporal and spatial variation in measured variables often peaked at intermediate mangrove cover, with ecological consequences that are largely unexplored. Because different processes varied in different ways with mangrove cover, the “optimum” cover of mangroves from a societal point of view will depend on which ecosystem services are most desired.
Iron controls over di‐nitrogen fixation in karst tropical forest
Authors: Winbourne Joy B. , Brewer Steven W. , Houlton Benjamin Z.
Published: December 2016

Limestone tropical forests represent a meaningful fraction of the land area in Central America (25%) and Southeast Asia (40%). These ecosystems are marked by high biological diversity, CO2 uptake capacity, and high pH soils, the latter making them fundamentally different from the majority of lowland tropical forest areas in the Amazon and Congo basins. Here, we examine the role of bedrock geology in determining biological nitrogen fixation (BNF) rates in volcanic (low pH) vs. limestone (high pH) tropical forests located in the Maya Mountains of Belize. We experimentally test how BNF in the leaf‐litter responds to nitrogen, phosphorus, molybdenum, and iron additions across different parent materials. We find evidence for iron limitation of BNF rates in limestone forests during the wet but not dry season (response ratio 3.2 ± 0.2; P = 0.03). In contrast, BNF in low pH volcanic forest soil was stimulated by the trace‐metal molybdenum during the dry season. The parent‐material induced patterns of limitation track changes in siderophore activity and iron bioavailability among parent materials. These findings point to a new role for iron in regulating BNF in karst tropical soils, consistent with observations for other high pH systems such as the open ocean and calcareous agricultural ecosystems.
Position Sensorless Control for IPMSM Based on Extended EMF and Voltage Injection Synchronized with Pulse‐Width Modulation Carrier
Authors: YOKOYAMA TOMOYA , UCHIDA KOUSUKE , KUBOTA HISAO
Published: December 2016

This paper presents a new position sensorless control system for an interior permanent magnet synchronous motor (IPMSM). The proposed method is based on the extended electromotive force (EMF) and voltage injection synchronized with a pulse‐width modulation carrier. The proposed method does not need to switch the estimation method by speed in order to estimate the magnetic pole position by extended EMF, even at low speeds. Further, the amplitude of the superimposing voltage is changed according to the extended EMF; the applied voltage is not saturated in the high‐load and high‐speed regions. The effectiveness of the proposed sensorless control system was verified experimentally.
Reducing Acoustic Noise of Axial‐Gap SRMs by Decreasing Axial Electromagnetic Force Ripple
Authors: TOKITA TAKAHIRO , GOTO HIROKI , ICHINOKURA OSAMU
Published: December 2016

Switched reluctance (SR) motors are motors that utilize the reluctance torque originating in the magnetic saliency between the stator and the rotor, which are made up of an electromagnetic steel sheet and windings without a permanent magnet. Because of their robustness and simple structure, SR motors are suited for use as the in‐wheel motor for traction motors of vehicles. In a flat space such as is present in in‐wheel motors, the axial‐gap structure has an advantage compared with the conventional radial‐gap structure for the space factor of a motor. An axial‐gap in‐wheel SR motor was tested in a microbus, and the bus could be successfully driven. The test results regarding the motor performance were satisfactory. However, the motor emits a loud sound. The acoustic noise of the axial‐gap SR motor is mainly caused by the axial electromagnetic force. This paper presents a method of reducing acoustic noise that is based on a model of the electromagnetic force on the axial‐gap SR motor.
Study on Rotary Loop Flow Controller for the Next‐Generation Distribution System
Authors: VERMA S. C. , YAMADA FUJIHIRO , KUNII YASUYUKI , UEDA FUKASHI , KURODA KENICHI , KITAYAMA MASASHI , KONO YOSHIYUKI
Published: December 2016

This paper describes two types of rotary loop flow controller, one is series type and the other is unified power flow controller (UPFC) type. Both of them can maintain the suitable voltage level of distribution system even with a large and uneven penetration of distributed generation. The configurations of proposed controllers are essentially same as wound rotor induction machine with no slip rings. The proposed controllers are less costly, more efficient, and more tolerant to overvoltages/currents as compared to power electronics‐type controllers. Further, UPFC‐type rotary loop flow controller has additional advantages like relatively smaller capability and ability to control reactive power than the series type of rotary loop flow controller. The proper functioning of the proposed controllers is confirmed through simulations and experiments.
Biological Evaluation of l‐Tyrosine Labelled with fac‐[99mTc(CO)3]+ at a para‐OH‐Coupled 2,3‐Diaminopropionic Acid Based Chelator
Authors: Felber Michael , Bauwens Matthias , Imstepf Sebastian , Fox Thomas , Mottaghy Felix M. , Alberto Roger
Published: December 2016

Radiolabeled amino acids as metabolic tracers are increasingly important for imaging and therapy applications. There are only a few reports on 99mTc‐labeled amino acids that have been evaluated in vivo. In this work we coupled a small and highly potent chelator for the fac‐[99mTc(CO)3]+ core to l‐tyrosine through a poly(ethylene glycol) linker and investigated the in vivo biodistribution of the 99mTc‐labeled l‐tyrosine derivative. In vivo evaluation and biodistribution in mice bearing C6‐tumor xenografts revealed little tumor and pancreas uptake. The microSPECT images showed rapid clearance from the blood pool. Fast uptake into the gallbladder and an extended residence time makes this labeled tyrosine suitable for gallbladder imaging and associated dysfunctions.
Ba32[Li15Si9W16N67O5]: A Barium‐Containing Oxonitridolithotungstosilicate with a Highly Condensed Network Structure
Authors: Horky Katrin , Schnick Wolfgang
Published: December 2016

The oxonitridolithotungstosilicate Ba32[Li15Si9W16N67O5] was synthesized by metathesis reaction of the reactive starting compounds Si(NH)2, LiNH2, LiF, and BaH2 in a radiofrequency furnace at 1000 °C by using tungsten crucibles. Single crystals of Ba32[Li15Si9W16N67O5] were obtained as a byproduct from reaction of the starting materials with the crucible. The crystal structure was solved and refined on the basis of single‐crystal X‐ray diffraction data [P21/n (no. 14), a = 8.3402(3), b = 8.5465(3), c = 16.6736(6) Å, β = 99.1950(10)°, Z = 1, R1(all) = 0.0302]. Ba32[Li15Si9W16N67O5] is the first oxonitridolithotungstosilicate containing a three‐dimensional network of vertex‐ (WN4) and edge‐sharing (LiN3O, Li/SiN3O, and SiN3O) tetrahedra with Ba2+ ions that fill the voids of the structure. The network is characterized by channels of fünfer rings running along [100] as well as channels of sechser and achter rings along [010]. Magnetic measurements verified an oxidation state of +VI for W. X‐ray spectroscopy, lattice energy calculations with MAPLE, and X‐ray diffraction confirmed the chemical composition and the structural model of Ba32[Li15Si9W16N67O5]. IR spectra corroborated the absence of N–H bonds. The optical band gap of Ba32[Li15Si9W16N67O5] has been determined by UV/Vis spectroscopy.
Mechanical pinprick pain in patients with unilateral spatial neglect: The influence of space representation on the perception of nociceptive stimuli
Authors: Vizzari V. , Barba S. , Gindri P. , Duca S. , Giobbe D. , Cerrato P. , Geminiani G. , Torta D.M.
Published: December 2016

Background

Crossing the hands over the midline can reduce the perceived intensity of nociceptive stimuli applied onto the hands. It remains unclear to what extent intact representation of peripersonal space influences this effect. Here we used the crossed‐hands paradigm in patients with unilateral spatial neglect, a neuropsychological condition characterized by the inability to detect, attend and respond to contralesional (most often left) stimuli, and spared ability to process stimuli in the non‐affected space.

Methods

Sixteen post‐stroke patients without unilateral neglect and 11 patients with unilateral spatial neglect received punctate mechanical pinprick stimuli onto their crossed or uncrossed hands. We tested: (i) whether deficits in space representation reduce the possibility of observing ‘crossed‐hands analgesia’, and; (ii) whether placing the contralesional hand, normally lying in the affected space in the healthy space would increase the number of detected stimuli.

Results

Our results showed that neglect patients did not exhibit ‘crossed‐hands’ analgesia, but did not provide strong evidence for an improvement in the number of detected stimuli when the contralesional hand was in the healthy space.

Conclusion

These findings uphold the notion that the perception of nociceptive stimuli is modulated by the relative position of the hands in space, but raise questions about the conditions under which these effects may arise.

Significance

We show that deficits in space representation can influence the processing of mechanical pinprick stimuli. Our results raise several questions on the mechanisms underlying these effects, which are relevant for the clinical practice.
Preoperative sleep quality predicts postoperative pain after planned caesarean delivery
Authors: Orbach‐Zinger S. , Fireman S. , Ben‐Haroush A. , Karoush T. , Klein Z. , Mazarib N. , Artyukh A. , Chen R. , Ioscovich A. , Eidelman L.A. , Landau R.
Published: December 2016

Background

Severe post‐caesarean pain remains an important issue associated with persistent pain and postpartum depression. Women's sleep quality prior to caesarean delivery and its influence on postoperative pain and analgesic intake have not been evaluated yet.

Methods

Women undergoing caesarean delivery with spinal anaesthesia (bupivacaine 12 mg, fentanyl 20 μg, morphine 100 μg) were evaluated preoperatively for sleep quality using the Pittsburgh Sleep Quality Index (PSQI) questionnaire (PSQI 0–5 indicating good sleep quality, PSQI 6–21 poor sleep quality). Peak and average postoperative pain scores at rest, movement and uterine cramping were evaluated during 24 h using a verbal numerical pain score (VNPS; 0 indicating no pain and 100 indicating worst pain imaginable), and analgesic intake was recorded. Primary outcome was peak pain upon movement during the first 24 h.

Results

Seventy‐eight of 245 women reported good sleep quality (31.2%; average PSQI 3.5 ± 1.2) and 167 poor sleep quality (68.2%; average PSQI 16.0 ± 3.4; p < 0.001). Women with poor sleep quality had significantly higher peak pain scores upon movement (46.7 ± 28.8 vs. 36.2 ± 25.6, respectively; p = 0.006). With multivariable logistic regression analysis, poor sleep quality significantly increased the risk for severe peak pain upon movement (VNPS ≥70; OR 2.64; 95% CI 1.2–6.0; p = 0.02).

Discussion

A significant proportion of women scheduled for caesarean delivery were identified preoperatively as having poor sleep quality, which was associated with more severe pain and increased analgesic intake after delivery. The PSQI score may therefore be a useful tool to predict increased risk for acute post‐caesarean pain and higher analgesic requirements, and help tailor anaesthetic management.

Significance

Multiple studies have evaluated predictors for severe acute pain after caesarean delivery that may be performed in a clinical setting, however, sleep quality prior to delivery has not been included in predictive models for post‐caesarean pain. The PSQI questionnaire, a simple test to administer preoperatively, identified that up to 70% of women report poor sleep quality before delivery, and poor sleep quality was associated with increased post‐caesarean pain scores and analgesic intake, indicating that PSQI could help identify preoperatively women at risk for severe pain after caesarean delivery.
β‐cyclodextrin‐ionic liquid polymer based dynamically coating for simultaneous determination of tetracyclines by capillary electrophoresis
Authors: Zhou Chunyan , Deng Jingjing , Shi Guoyue , Zhou Tianshu
Published: December 2016

Tetracyclines are a group of broad spectrum antibiotics widely used in animal husbandry to prevent and treat diseases. However, the improper use of tetracyclines may result in the presence of their residues in animal tissues or waste. Recently, great attention has been drawn towards the green solvents ionic liquids. Ionic liquids have been employed as a coating material to modify the electroosmotic flow in capillary electrophoresis. In this study, a functionalized ionic liquid, mono‐6‐deoxy‐6‐(3‐methylimidazolium)‐β‐cyclodextrin tosylate, was synthesized and used for the simultaneous separation and quantification of tetracyclines by capillary electrophoresis. Good separation efficiency could be achieved due to the multiple functions of β‐cyclodextrin derived ionic liquid, including the electrostatic interaction, the hydrogen bonding, and the cavity structure in β‐cyclodextrin ionic liquid which can entrap the tetracyclines to form inclusion complex. After optimization, baseline separation achieved in 25 min with the running buffer consisted of 10 mmol/L, pH 7.2 phosphate buffer and 20 mmol/L β‐cyclodextrin ionic liquid. The satisfied result demonstrated that the β‐cyclodextrin ionic liquid is an ideal background electrolyte modifier in the separation of tetracyclines with high stability and good reproducibility. And it is an effective strategy to design and synthesize specific ILs as additive applied in separation.