bluuebunny/crossref_metadata_2025 huggingface dataset:
Kontrolle der Freisetzungskinetik von Nanopartikeln aus 3D‐gedruckten Hydrogelgerüsten
Authors: Baumann Bernhard , Jungst Tomasz , Stichler Simone , Feineis Susanne , Wiltschka Oliver , Kuhlmann Matthias , Lindén Mika , Groll Jürgen
Published: March 2017

Die bisher größtenteils unerforschte Kombination aus Biofabrikation und Nanotechnologie ermöglicht eine örtlich und zeitlich aufgelöste Freisetzung von Wirkstoffen aus hierarchischen, zellbeladenen Biomaterialien. Als ein erster Schritt in Richtung der Verknüpfung dieser beiden Forschungsgebiete wird hier gezeigt, dass die Einstellung der elektrostatischen Nanopartikel‐Polymer‐ und Nanopartikel‐Nanopartikel‐Wechselwirkungen verwendet werden kann, um die Freisetzungskinetik von Nanopartikeln aus gedruckten 3D Hydrogelgerüsten zu steuern. Diese grundlegende Strategie kann für die räumliche und zeitliche Kontrolle der Freisetzungskinetik von nanopartikulären Wirkstoffträgern in biofabrizierten Konstrukten verwendet werden.
HACA's Heritage: A Free‐Radical Pathway to Phenanthrene in Circumstellar Envelopes of Asymptotic Giant Branch Stars
Authors: Yang Tao , Kaiser Ralf I. , Troy Tyler P. , Xu Bo , Kostko Oleg , Ahmed Musahid , Mebel Alexander M. , Zagidullin Marsel V. , Azyazov Valeriy N.
Published: March 2017

The hydrogen‐abstraction/acetylene‐addition (HACA) mechanism has been central for the last decades in attempting to rationalize the formation of polycyclic aromatic hydrocarbons (PAHs) as detected in carbonaceous meteorites such as in Murchison. Nevertheless, the basic reaction mechanisms leading to the formation of even the simplest tricyclic PAHs like anthracene and phenanthrene are still elusive. Here, by exploring the previously unknown chemistry of the ortho‐biphenylyl radical with acetylene, we deliver compelling evidence on the efficient synthesis of phenanthrene in carbon‐rich circumstellar environments. However, the lack of formation of the anthracene isomer implies that HACA alone cannot be responsible for the formation of PAHs in extreme environments. Considering the overall picture, alternative pathways such as vinylacetylene‐mediated reactions are required to play a crucial role in the synthesis of complex PAHs in circumstellar envelopes of dying carbon‐rich stars.
Working with Religious and Spiritual Experience in Family Therapy: Manna for the Journey
Authors: Pearson Alastair
Published: March 2017

For many family therapists, exploring religion and spirituality with clients can be challenging. Despite notable contributions to the systemic literature over the last 30 years, family therapy continues to tell the story that this is risky territory. In this article I share the personal and professional stories of a number of family therapists brought together in focus groups to discuss personal and professional beliefs and practices in relation to religion and spirituality. The range of perspectives and issues explored renders these encounters a rich resource for family therapists wishing to develop their practice. Connections are made between themes from the discussions and the literature, and ideas proposed to support the development of positive dialogue between family therapists across the faith/secular spectrum.
A Strategy to Design Hyperpolarized 13C Magnetic Resonance Probes Using [1‐13C]α‐Amino Acid as a Scaffold Structure
Authors: Nishihara Tatsuya , Kameyama Yutaka , Nonaka Hiroshi , Takakusagi Yoichi , Hyodo Fuminori , Ichikawa Kazuhiro , Sando Shinsuke
Published: March 2017

Hyperpolarization is an emerging method that dramatically enhances NMR signal intensity. As a result of their increased sensitivity, hyperpolarized (HP) NMR molecular probes can be used to perform time‐resolved spectroscopy and imaging in vitro and in vivo. It is, however, challenging to design such probes de novo. Herein, the [1‐13C]α‐amino acid is reported as a scaffold structure to design HP 13C NMR molecular probes. The [1‐13C]α‐amino acid can be converted to various HP 13C chemical probes that show sufficient chemical shift change by altering the chemical state of the α nitrogen upon interaction with the target. Several previously reported HP probes could be explained by this design principle. To demonstrate the versatility of this approach, two α‐amino‐acid‐based HP 13C chemical probes, sensitive to pH and Ca2+ ion, were developed and used to detect targets.
Covalent Crosslinking of Graphene Quantum Dots by McMurry Deoxygenation Coupling
Authors: Chen Limei , Hu Peiguang , Lu Jia En , Chen Shaowei
Published: March 2017

Graphene quantum dots were covalently crosslinked forming ensembles of a few hundred nanometers in size by McMurry deoxygenation coupling reactions of peripheral carbonyl functional moieties catalyzed by TiCl4 and Zn powders in refluxing THF, as evidenced by TEM, AFM, FTIR, Raman and XPS measurements. Photoluminescence measurements showed that after chemical coupling, the excitation and emission peaks blue‐shifted somewhat and the emission intensity increased markedly, likely due to the removal of oxygenated species where quinone‐like species are known to be effective electron acceptors and emission quenchers.
Dasatinib inhibits actin fiber reorganization and promotes endothelial cell permeability through RhoA‐ROCK pathway
Authors: Dasgupta Swapan K. , Le Anhquyen , Vijayan K. Vinod , Thiagarajan Perumal
Published: March 2017

Treatment with dasatinib, a tyrosine kinase inhibitor, is associated with edema, pleural effusion, and pulmonary edema. We investigated the effect of dasatinib on the barrier function of human microvascular endothelial cells‐1 (HMEC‐1) in vitro and in vivo. The permeability of HMEC‐1 to fluorescein isothiocyante (FITC)‐dextran increased in Transwell chambers within 5 min following the addition of therapeutic concentrations of dasatinib. The change in permeability was associated with increased activation of RhoA GTPase and its effector Rho‐associated coiled‐coil kinase 1(ROCK1). RhoA inhibitor C3 transferase almost completely inhibited dasatinib‐induced increase in permeability. Under similar conditions, imatinib had no effect on permeability or activation of RhoA. Since integrin‐induced cell spreading suppresses RhoA activation, we examined the effect of dasatinib on cell spreading on fibronectin substrate. Dasatinib impaired endothelial cell spreading in a concentration‐dependent manner and induced disorganization of actin fibers. Tyrosine kinases play an essential role in transmitting signals from integrins to RhoA and we examined tyrosine phosphorylation of several cytoskeletal proteins. Dasatinib markedly inhibited tyrosine phosphorylation of p130 Crk‐associated substrate (p130cas), paxillin and vinculin. These results suggest that the inhibition of tyrosine phosphorylation of the focal adhesion plaque components by dasatinib may alter the assembly of actin fibers resulting in the activation of RhoA/ROCK pathway. Consistent with these findings, dasatinib‐induced increase in the permeability was blocked by ROCK inhibitor y27632. In vivo administration of y27632, significantly inhibited the dasatinib‐induced extravasation of Evans blue in mice and dasatinib‐induced increase in microvascular permeability was attenuated in ROCK1‐deficient mice. These findings suggest that ROCK inhibitors could serve as therapeutic modalities to ameliorate the dasatinib‐induced pulmonary changes.
Dravet syndrome: a new causative SCN1A mutation?
Authors: Poryo Martin , Clasen Oriana , Oehl‐Jaschkowitz Barbara , Christmann Alexander , Gortner Ludwig , Meyer Sascha
Published: March 2017

Key Clinical Message

Dravet syndrome is often caused by SCN1A mutations and has a wide variation in clinical appearance. Indication for genetic analysis should be an epileptic encephalopathy or severe clinical course of seizures in infants with episodes of fever before the first year of life.
Concerted Catalysis in Tight Spaces: Palladium‐Catalyzed Allylation Reactions Accelerated by Accumulated Active Sites in Mesoporous Silica
Authors: Motokura Ken , Ikeda Marika , Nambo Masayuki , Chun Wang‐Jae , Nakajima Kiyotaka , Tanaka Shinji
Published: March 2017

The surface of mesoporous silica was modified with a Pd–bisphosphine complex and/or a tertiary amine group for concerted acceleration of allylation reactions. Mesoporous‐silica‐supported catalysts with a 1.6 nm pore diameter showed higher performance than nonporous or larger mesoporous silica‐supported catalysts owing to the accumulation of active sites into a confined space. For the case in which allyl alcohol was used in the reaction, the presence of a silanol group on the surface was quite effective: the turnover number of Pd was nine times greater than that of the homogeneous Pd complex.
A Fluorine‐18 Radiolabeling Method Enabled by Rhenium(I) Complexation Circumvents the Requirement of Anhydrous Conditions
Authors: Klenner Mitchell A. , Pascali Giancarlo , Zhang Bo , Sia Tiffany R. , Spare Lawson K. , Krause‐Heuer Anwen M. , Aldrich‐Wright Janice R. , Greguric Ivan , Guastella Adam J. , Massi Massimiliano , Fraser Benjamin H.
Published: March 2017

Azeotropic distillation is typically required to achieve fluorine‐18 radiolabeling during the production of positron emission tomography (PET) imaging agents. However, this time‐consuming process also limits fluorine‐18 incorporation, due to radioactive decay of the isotope and its adsorption to the drying vessel. In addressing these limitations, the fluorine‐18 radiolabeling of one model rhenium(I) complex is reported here, which is significantly improved under conditions that do not require azeotropic drying. This work could open a route towards the investigation of a simplified metal‐mediated late‐stage radiofluorination method, which would expand upon the accessibility of new PET and PET‐optical probes.
Synthesis of ortho‐Azophenols by Formal Dehydrogenative Coupling of Phenols and Hydrazines or Hydrazides
Authors: Esguerra Kenneth Virgel N. , Lumb Jean‐Philip
Published: March 2017

Azophenols are important chromophores and reagents in organic synthesis, with applications as pigments and molecular switches. Here, we describe a catalytic aerobic process that couples phenols and hydrazines or hydrazides for their synthesis. The key aromatic C−N bond is formed by condensation between the hydrazine or hydrazide and an ortho‐quinone, which triggers a redox‐isomerization to install the azo‐functionality. Notable features include rapid access to highly functionalized azophenols with a range of electronic configurations, including “push–pull” systems, conditions that employ simple, unactivated substrates, occurrence at room temperature using an earth‐abundant and commercially available copper catalyst, and production of water as the only stoichiometric byproduct.
Chiral exploration of 6,12‐diphenyldibenzo[b,f][1,5]diazocine with stable conformation
Authors: Li Zheng‐Yi , Pan Yong , Jin Lin‐Lin , Yin Yue , Yang Bao‐Zhu , Sun Xiao‐Qiang
Published: March 2017

A first optical resolution of 6,12‐diphenyldibenzo[b,f][1,5]diazocine with stable boat conformation was achieved by chiral supercritical fluid chromatography (SFC). The absolute configurations of enantiomers were first assigned and determined by X‐ray crystal structure based on CIP‐rules. The high optical rotation and circular dichroism spectrum were well explained by electronic helix theory. Owing to the high stabilization of boat conformation, the chiral configuration could be maintained at very high temperature, more than 200 °C, which was proved by Density Functional Theory calculations.
Operational Criteria for the Separation of Alkanes by Zeolite Membranes
Authors: Dragomirova Radostina , Jorabchi Majid Namayandeh , Paschek Dietmar , Wohlrab Sebastian
Published: March 2017

Operational criteria for the adsorption based separation of alkanes by MFI zeolite membranes were evaluated using the model system n‐butane in methane. The influence of operation parameters is rather case sensitive and the separation is determined by the interplay between mobility of adsorbed molecules across the membrane and the depletion of the preferred adsorptive agent, n‐butane, along the membrane. Different aspects in the operational design for the separation of alkanes by zeolite membranes were illuminated, namely separation task, stationarity, and membrane surface.
Über den Technologiewandel in der Propylenoxid‐Herstellung
Authors: Bernhard Maik , Anton Johan , Schmidt Franz , Sandkaulen Florian , Pascaly Matthias
Published: March 2017

Propylenoxid (PO) ist eines der industriell wichtigsten chemischen Zwischenprodukte. Es dient als Ausgangsverbindung für die Herstellung von Schaumstoffen, Lösungsmitteln oder Enteisungsmitteln und leistet damit einen wichtigen Beitrag für das moderne Leben. Traditionell erfolgt die Herstellung von PO nach dem Chlorhydrin‐Verfahren, das noch heute die größte Bedeutung besitzt. Die umweltfreundlichere und chlorfreie Herstellung von PO erlauben die Koppelproduktverfahren SM‐PO und MTBE‐PO, bei denen Styrol und MTBE als Folgeprodukte anfallen. Die Wirtschaftlichkeit dieser Verfahren wird demnach nicht nur durch das PO sondern auch durch die Nachfrage der Folgeprodukte bestimmt. Eine Weiterentwicklung des SM‐PO‐Verfahrens ist das CU‐PO‐Verfahren, bei dem kein Folgeprodukt anfällt. Die Entwicklung des hochselektiven Katalysators Titansilikalit‐1 (TS‐1) gepaart mit der verbesserten Verfügbarkeit großer Mengen von Wasserstoffperoxid ermöglichte die großtechnische Realisierung der koppelproduktfreien HPPO‐Technologie an mehreren Standorten weltweit. Dieses neue Verfahren ermöglicht die Herstellung von PO mit ausgezeichneten Ausbeuten und Selektivitäten, wobei ausschließlich Wasser als umweltfreundliches Nebenprodukt anfällt. Der Einsatz homogener Katalysatoren sowie die einstufige Direktoxidation von Propylen mit Luft bzw. Sauerstoff sind bislang nur von akademischer Bedeutung.
Development of model systems for in vitro investigation of transdermal transport pathways
Authors: Liuzzi Roberta , Preziosi Valentina , Caserta Sergio , Guido Stefano
Published: March 2017

Skin is a complex structured system primarily involved in Transdermal Drug Delivery (TDD). The outer stratum corneum represents the main barrier to the entrance of external molecules. Nowadays, none of the recognized methods, used for the investigation of penetration processes, is able to give a complete overview of the transport mechanisms involved. Standard protocols are based on the use of human or animal skin samples, which are difficult and expensive to obtain. Here, we present a novel experimental setup to investigate TDD by using Confocal Laser Scanning Microscopy and image analysis. The methodology is based on diffusion experiments of fluorescent‐labelled fluids (water, oil, and oil‐in‐water emulsions), in a model matrix. Using an agarose gel as model for a proof of concept, different penetration efficiencies were observed, suggesting an important role of both chemical composition and fluid microstructure on the transport mechanism. An adequate model system should be used to better mimic the stratum corneum morphology and properties. To this aim, several bicontinuous emulsion gels, obtained from an emulsification process, were preliminary formulated and suggested as model systems to mimic the stratum corneum. In this work, we define the key directions for the development of an innovative approach to study the penetration of formulations through the skin.
Salinity tolerance, adsorption, and emulsification properties of nonylphenol alkyl sulphonates derived from bi‐component linear alpha olefin
Authors: Niu Ruixia , Wang Daqiang , Long Biao , Song Hua , Wang Chao , Wang Jingling , He Junyao
Published: March 2017

A series of bi‐component nonylphenol alkyl sulphonate surfactants with different alkyl chains (C12/n‐NPAS, n = 8, 10, 14, 16) were synthesized through sulphonation‐alkylation‐neutralization, using a mixture of linear alpha olefins as raw materials. The chemical structures were characterized by FTIR and ESI‐MS. The purity values measured by the two‐phase titration method were all higher than 0.96 g/g (96 wt%). The effects of the raw materials composition on salinity tolerance, adsorption, and emulsification properties were also investigated. There is marked adsorption amount variation for bi‐component surfactants with a strong difference of carbon number of alkyl groups. The salinity tolerance of C12/n‐NPAS is about 40 g · L−1 of NaCl, and 0.65 g · L−1 of CaCl2. Compared with petroleum sulphonates (14 g · L−1 of NaCl, 0.08 g · L−1 of CaCl2) and LAS (22 g · L−1 of NaCl, 0.37 g · L−1 of CaCl2), NPAS surfactants show a low adsorption, excellent salinity tolerance, and emulsion stability.
A binder‐free Ir0.4Ru0.6‐oxide/functionalized multi‐walled carbon nanotube electrode for possible applications in supercapacitors
Authors: McArthur Mark A. , Ullah Nehar , Coulombe Sylvain , Omanovic Sasha
Published: March 2017

An initial study on a simple and inexpensive method to form an Ir0.4Ru0.6‐oxide (MMO) coating onto high‐area plasma functionalized multi‐walled carbon nanotubes (f‐MWCNTs) at the bench‐scale for possible supercapacitor (SC) applications is presented. f‐MWCNT electrodes are prepared in a two‐step process combining the growth of MWCNTs directly onto a 316 stainless steel mesh by thermal‐chemical vapour deposition (t‐CVD), followed by the addition of oxygen‐containing functionalities to their surface by plasma functionalization. The plasma functionalization step is done to: (i) improve electrode wettability and (ii) improve capacitive properties through the addition of pseudocapacitive oxygen functionalities. A simple dip‐dry method is then employed to coat the f‐MWCNTs with the desired MMO coating (Ir0.4Ru0.6‐oxide) prepared initially in a liquid precursor mixture. f‐MWCNT electrodes are suspended and dipped into the precursor then heated in air to evaporate the solvent while building the oxide layer. The resulting MMO/f‐MWCNT electrode exhibits excellent stability in 4 mol/L KOH electrolyte, yielding larger specific capacitance values than those obtained on bare f‐MWCNT electrodes; at a charging/discharging current density of 0.5 mA cm−2, the MMO/f‐MWCNT and f‐MWCNT electrodes achieve specific capacitances of 664 ± 7 and 190 ± 30 F g−1 in a 3‐electrode cell, respectively. The MMO/f‐MWCNT electrodes show good rate capability performance up to 10 mA · cm−2 and excellent stability.
Methylene blue adsorption using chabazite: Kinetics and equilibrium modelling
Authors: Solisio Carlo , Aliakbarian Bahar
Published: March 2017

The adsorption of methylene blue from aqueous solution by a natural zeolite (chabazite) was studied. The effect of adsorbate concentration and pH were evaluated using raw and acid‐treated chabazite. Fourier transform infrared spectroscopy analysis revealed surface modification of acid‐treated chabazite, thus resulting in a decrease in adsorption capacity. The sorption kinetics and the equilibrium isotherms were evaluated. The pseudo‐second‐order model was found to be the most suited for kinetic results, and the Langmuir isotherm was chosen to better describe the sorption system. The results confirmed the efficacy of raw chabazite in removing almost all methylene blue fraction from the solution. The use of such a material, at low cost and easily available, can therefore represent a possible efficient way to remove dyes from effluent of many industries.
Hydraulic and disinfection efficiency of an ozonation contactor for a municipal water treatment plant using computational fluid dynamics
Authors: Niazi Shahram , Kalbasi Mansour , Bahramian Alireza
Published: March 2017

Determination of hydrodynamic characteristics and disinfection efficiency are important factors in the operational study of the ozone contactors. In the present work, a full‐scale ozonation contactor for a municipal water treatment plant was simulated by computational fluid dynamics (CFD) approach. The Eulerian multiphase, k–ϵ turbulence, and kinetic‐based reaction models were implemented in a finite volume framework to predict the hydraulic parameters, ozone concentration distribution, total organic carbon (TOC) reduction, and concentration‐contact time (CT) values in the contactor. The reaction kinetics for ozone decay was determined by experimental data collected via the contactor. The quality of mesh near the walls and the results independence on the mesh density were probed to determine the optimal grid density. For the first time, the accuracy of the model was evaluated in contrast with experimental data of TOC reductions during ozonation process. The pulse tracer study and flow field indicated recirculation, dead zones, and therefore non‐optimized baffle configuration in the contactor. The predicted CT values indicated that in the cold and hot months, the ozone dosage must increase by a factor of 3–5 relative to the current dosage values to achieve disinfection log‐inactivation credit for pathogens. Using the CFD simulation results, the correlation between ozone dosage and CT values for the hot and cold months in the ozonation contactor was predicted.
Primary atomization of electrified water sprays
Authors: Manna Lucia , Carotenuto Claudia , Nigro Roberto , Lancia Amedeo , Di Natale Francesco
Published: March 2017

This study reports experimental results on the primary jet breakup parameters of three hollow cone hydraulic spray nozzles electrified by induction. While former evidence indicated that the properties of sprayed droplets are scarcely affected by induction charging, we found that an increase in charging potential from 0 kV to −10 kV led to a reduction of breakup length and an increase of spray angle. For charging potential from −10 kV and −12 kV both the parameters reached asymptotic levels. As for electrosprays, we argue that jet breakup reduction modifications depend on the establishment of electrical stresses over the water sheet, while spray angle enlargements depend on the repulsion forces caused by induced charges. In most of the cases, these modifications are not sufficient to change the secondary atomization regime, but they severely affect the charging level of sprayed droplets.
A phase 1 study to evaluate the safety and LDL cholesterol–lowering effects of RG7652, a fully human monoclonal antibody against proprotein convertase subtilisin/kexin type 9
Authors: Baruch Amos , Luca Diana , Kahn Robert S. , Cowan Kyra J. , Leabman Maya , Budha Nageshwar R. , Chiu Cecilia P.C. , Wu Yan , Kirchhofer Daniel , Peterson Andrew , Davis Jr John C. , Tingley Whittemore G.
Published: March 2017

Background

Proprotein convertase subtilisin/kexin type 9 (PCSK9) downregulates low‐density lipoprotein (LDL) receptors, thereby leading to a rise in circulating LDL cholesterol (LDL‐C). RG7652 is a fully human monoclonal antibody against PCSK9. This placebo‐controlled, phase 1 ascending‐dose study in healthy subjects evaluated the safety of RG7652 and its efficacy as a potential LDL‐C–lowering drug.

Hypothesis

Anti‐PCSK9 antibody therapy safely and effectively reduces LDL‐C.

Methods

Subjects (N = 80) were randomized into 10 cohorts. Six sequential single‐dose cohorts received 10, 40, 150, 300, 600, or 800 mg of RG7652 via subcutaneous injection. Four multiple‐dose cohorts received 40 or 150 mg of RG7652 once weekly for 4 weeks, either with or without statin therapy (atorvastatin).

Results

Adverse events (AEs) were generally mild; the most common AEs were temporary injection‐site reactions. No serious AEs, severe AEs, AEs leading to study‐drug discontinuation, or dose‐limiting toxicities were reported. RG7652 monotherapy reduced mean LDL‐C levels by up to 64% and as much as 100 mg/dL at week 2; the effect magnitude and duration increased with dose (≥57 days following a single RG7652 dose ≥300 mg). Exploratory analyses showed reduced oxidized LDL, lipoprotein(a), and lipoprotein‐associated phospholipase A2 with RG7652. Antidrug antibody against RG7652 tested positive in 2 of 60 (3.3%) RG7652‐treated and in 4 of 20 (20.0%) placebo‐treated subjects. Simultaneous atorvastatin administration did not appear to impact the pharmacokinetic profile or lipid‐lowering effects of RG7652.

Conclusions

Overall, RG7652 elicited substantial and sustained dose‐related LDL‐C reductions with an acceptable safety profile and minimal immunogenicity.
N‐Guanidino Derivatives of 1,5‐Dideoxy‐1,5‐imino‐d‐xylitol are Potent, Selective, and Stable Inhibitors of β‐Glucocerebrosidase
Authors: Sevšek Alen , Šrot Luka , Rihter Jakob , Čelan Maša , van Ufford Linda Quarles , Moret Ed E. , Martin Nathaniel I. , Pieters Roland J.
Published: March 2017

A series of lipidated guanidino and urea derivatives of 1,5‐dideoxy‐1,5‐imino‐d‐xylitol were prepared from d‐xylose using a concise synthetic protocol. Inhibition assays with a panel of glycosidases revealed that the guanidino analogues display potent inhibition against human recombinant β‐glucocerebrosidase with IC50 values in the low nanomolar range. Related urea analogues of 1,5‐dideoxy‐1,5‐imino‐d‐xylitol were also synthesized and evaluated in the same fashion and found to be selective for β‐galactosidase from bovine liver. No inhibition of human recombinant β‐glucocerebrosidase was observed for the urea analogues. Computational studies provided insight into the potent activity of analogues bearing the substituted guanidine moiety in the inhibition of lysosomal glucocerebrosidase (GBA).
Acute lymphoblastic leukemia in adolescents and young adults
Authors: Rytting Michael E. , Jabbour Elias J. , O'Brien Susan M. , Kantarjian Hagop M.
Published: March 2017

Acute lymphoblastic leukemia (ALL) in the adolescent and young adult (AYA) population is a difficult clinical problem. The AYA population, generally regarded as patients aged 15 to 39 years, currently draws a good deal of attention, particularly in the area of therapy selection. The current trend is to treat this group of patients with leukemia regimens based on pediatric protocols, and results comparing pediatric approaches versus adult approaches to treatment are maturing. Results are pending from a large US trial in which pediatric‐based treatment is given to AYA patients with ALL. In tandem with these new clinical trials, researchers have reported disease features in the AYA group that may explain some of the differences in response to treatment observed in the AYA population compared with the pediatric population. In addition, unique social factors in this age group add to the complexity of ALL therapy in the AYA population. AYA patients are developing independence and separating from their parents. They tend to be noncompliant. Young adults suffer from a lack of health care insurance and poor access to clinical trials, and have specific concerns regarding toxicities, in particular fertility. Cancer 2017;123:2398–403. © 2017 American Cancer Society.
5‐HT3A‐driven green fluorescent protein delineates gustatory fibers innervating sour‐responsive taste cells: A labeled line for sour taste?
Authors: Stratford J. M. , Larson E. D. , Yang R. , Salcedo E. , Finger T. E.
Published: March 2017

Taste buds contain multiple cell types with each type expressing receptors and transduction components for a subset of taste qualities. The sour sensing cells, Type III cells, release serotonin (5‐HT) in response to the presence of sour (acidic) tastants and this released 5‐HT activates 5‐HT3 receptors on the gustatory nerves. We show here, using 5‐HT3AGFP mice, that 5‐HT3‐expressing nerve fibers preferentially contact and receive synaptic contact from Type III taste cells. Further, these 5‐HT3‐expressing nerve fibers terminate in a restricted central‐lateral portion of the nucleus of the solitary tract (nTS)—the same area that shows increased c‐Fos expression upon presentation of a sour tastant (30 mM citric acid). This acid stimulation also evokes c‐Fos in the laterally adjacent mediodorsal spinal trigeminal nucleus (DMSp5), but this trigeminal activation is not associated with the presence of 5‐HT3‐expressing nerve fibers as it is in the nTS. Rather, the neuronal activation in the trigeminal complex likely is attributable to direct depolarization of acid‐sensitive trigeminal nerve fibers, for example, polymodal nociceptors, rather than through taste buds. Taken together, these findings suggest that transmission of sour taste information involves communication between Type III taste cells and 5‐HT3‐expressing afferent nerve fibers that project to a restricted portion of the nTS consistent with a crude mapping of taste quality information in the primary gustatory nucleus.
Efficient quality of service‐aware packet chunking scheme for machine‐to‐machine cloud services
Authors: Sawabe Anan , Tsukamoto Kazuya , Oie Yuji
Published: March 2017

With the recent advances in machine‐to‐machine communications, huge numbers of devices have become connected and massive amounts of traffic are exchanged. Machine‐to‐machine applications typically generate small packets, which can profoundly affect the network performance. Namely, even if the packet arrival rate at the router is lower than the link bandwidth, bits per second, it can exceed the router forwarding capacity, which indicates the maximum number of forwarded packets per second. This will cause the decrease in the network throughput. Therefore, eliminating the packets per second limitation by chunking small packets will enable machine‐to‐machine cloud services to spread further. This paper proposes new packet‐chunking schemes aimed at meeting both application requirements and improving achievable router throughput. In our schemes, multiple buffers, each of which accommodates packets classified based on their delay requirement, are installed in parallel. Herein, we report on analysis of the theoretically performance of these schemes, which enabled us to derive some important features. We also propose a scheme whereby a single chunking buffer and parallel multiple buffers were arranged in tandem. Through our simulation and numerical results, we determined that these schemes provide excellent performance in reducing the number of outgoing packets from the router while meeting various delay requirements.
Study of low‐frequency oscillations in a double‐stage Hall thruster
Authors: Zhang Xu , Ding Yongjie , Han Liang , Wei Liqiu , Yu Daren
Published: March 2017

The characteristics of low‐frequency oscillations of double‐stage Hall thrusters are quite different from those of conventional single‐stage Hall thrusters. In this paper, the effects of double‐stage discharge on the low‐frequency oscillations are experimentally investigated. The results indicate that the amplitude significantly decreases with increasing magnetic field strength and voltage during the ionization stage. Meanwhile, data analysis reveals that ionization occurs in both stages and that the transport ion current between the two stages is the key factor that affects the amplitude and main frequency of the oscillations. Two new processes, namely the ion transport and ion recombination caused by double‐stage discharge, are found to be relevant to the change in the current oscillations. To summarize, the ionization stage relieves the oscillations in the acceleration stage, leading to a reduction in the amplitude of the discharge current.
Hatching date variability in wild populations of four coexisting species of African annual fishes
Authors: Reichard Martin , Blažek Radim , Polačik Matej , Vrtílek Milan
Published: March 2017

Background: Hatching is modulated by a combination of intrinsic and extrinsic factors. Annual killifish are adapted to complete their entire life cycle in annually desiccating habitats. Spending most of their life in the embryonic stage, they have evolved adaptations to survive desiccated conditions and match their hatching with the unpredictable onset of the aquatic phase of the pool. We examined spatial and temporal synchrony of hatching in natural populations of four species of African annual killifish (genus Nothobranchius). We compared differences and variability in hatching dates among years, regions, pools, and species and matched them with data on inundations of individual pools. Results: Inundations typically coincided with peak rainfall in early January. We found considerable spatial and temporal synchrony in 1 year, but less synchrony in the other 2 years. Hatching generally occurred 0–20 days after inundation; fish at most sites hatched synchronously (<1 week) but some sites showed protracted hatching or two age cohorts. One species tended to hatch earlier than the other three. Conclusions: We suggest that hatching of annual killifish in the wild is a result of the interplay between environmental conditions and individual predisposition to respond to threshold environmental cues, ensuring effective bet‐hedging against unpredictable inundation. Developmental Dynamics 246:827–837, 2017. © 2017 Wiley Periodicals, Inc.
Patterns in Greater Sage‐grouse population dynamics correspond with public grazing records at broad scales
Authors: Monroe Adrian P. , Aldridge Cameron L. , Assal Timothy J. , Veblen Kari E. , Pyke David A. , Casazza Michael L.
Published: March 2017

Human land use, such as livestock grazing, can have profound yet varied effects on wildlife interacting within common ecosystems, yet our understanding of land‐use effects is often generalized from short‐term, local studies that may not correspond with trends at broader scales. Here we used public land records to characterize livestock grazing across Wyoming,USA, and we used Greater Sage‐grouse (Centrocercus urophasianus) as a model organism to evaluate responses to livestock management. With annual counts of male Sage‐grouse from 743 leks (breeding display sites) during 2004–2014, we modeled population trends in response to grazing level (represented by a relative grazing index) and timing across a gradient in vegetation productivity as measured by the Normalized Vegetation Difference Index (NDVI). We found grazing can have both positive and negative effects on Sage‐grouse populations depending on the timing and level of grazing. Sage‐grouse populations responded positively to higher grazing levels after peak vegetation productivity, but populations declined when similar grazing levels occurred earlier, likely reflecting the sensitivity of cool‐season grasses to grazing during peak growth periods. We also found support for the hypothesis that effects of grazing management vary with local vegetation productivity. These results illustrate the importance of broad‐scale analyses by revealing patterns in Sage‐grouse population trends that may not be inferred from studies at finer scales, and could inform sustainable grazing management in these ecosystems.
Screening mitochondrial DNA sequence variation as an alternative method for tracking established and outbreak populations of Queensland fruit fly at the species southern range limit
Authors: Blacket Mark J. , Malipatil Mali B. , Semeraro Linda , Gillespie Peter S. , Dominiak Bernie C.
Published: March 2017

Understanding the relationship between incursions of insect pests and established populations is critical to implementing effective control. Studies of genetic variation can provide powerful tools to examine potential invasion pathways and longevity of individual pest outbreaks. The major fruit fly pest in eastern Australia, Queensland fruit fly Bactrocera tryoni (Froggatt), has been subject to significant long‐term quarantine and population reduction control measures in the major horticulture production areas of southeastern Australia, at the species southern range limit. Previous studies have employed microsatellite markers to estimate gene flow between populations across this region. In this study, we used an independent genetic marker, mitochondrial DNA (mtDNA) sequences, to screen genetic variation in established and adjacent outbreak populations in southeastern Australia. During the study period, favorable environmental conditions resulted in multiple outbreaks, which appeared genetically distinctive and relatively geographically localized, implying minimal dispersal between simultaneous outbreaks. Populations in established regions were found to occur over much larger areas. Screening mtDNA (female) lineages proved to be an effective alternative genetic tool to assist in understanding fruit fly population dynamics and provide another possible molecular method that could now be employed for better understanding of the ecology and evolution of this and other pest species.
Phylogeny and biogeography of the scaleless scale worm Pisione (Sigalionidae, Annelida)
Authors: Gonzalez Brett C. , Petersen Haidi Cecilie B. , Di Domenico Maikon , Martínez Alejandro , Armenteros Maickel , García‐Machado Erik , Møller Peter Rask , Worsaae Katrine
Published: March 2017

Pisione is a scaleless group of small scale worms inhabiting sandy bottoms in shallow marine waters. This group was once considered rare, but now 45 described species can be characterized, among others, by their paired, segmental copulatory organs (one to multiple external pairs), which display a complexity of various accessory structures. The evolutionary significance of these unique organs was suggested in the late 1960s, but has been heavily debated since the late 1990s and remains controversial. In the present paper, we study the internal relationships within Pisione, employing combined phylogenetic analyses of both molecular and morphological data from 16 terminals of Pisione, as well as two terminals of Pisionidens, and eight additional scale worms as outgroups. Our taxon sampling covers all geographical areas where the genus has been reported, as well as most of their morphological and copulatory variability, including representatives of the “africana,” “remota,” “crassa,” and “papuensis” groups, established previously by Yamanishi. We hereby provide a first insight into the relationships of the genus, testing previously proposed hypotheses on the evolutionary significance of male copulatory structures within Pisione, while attempting to understand patterns of distribution. The phylogenetic analyses using maximum likelihood and Bayesian methods consistently recovered two large clades spanning the East Atlantic (including the Mediterranean) and the Indo‐Pacific–West Atlantic, respectively. Character optimization on our trees revealed a high degree of homoplasy in both non‐reproductive and sexual characters of Pisione, with buccal acicula found to be the sole apomorphy among the morphological features assessed herein, with none defining the biogeographical subclades within. Overall, our comparative analyses highlight the high degree of morphological variation in this widely distributed genus, rejecting previous assertions of an increasing number and complexity of copulatory structures across the genus.
Temperature increase and fluctuation induce phytoplankton biodiversity loss – Evidence from a multi‐seasonal mesocosm experiment
Authors: Rasconi Serena , Winter Katharina , Kainz Martin J.
Published: March 2017

Global climate change scenarios predict lake water temperatures to increase up to 4°C and extreme weather events, including heat waves and large temperature fluctuations, to occur more frequently. Such changes may result in a reorganization of the plankton community structure, causing shifts in diversity and structure toward a community dominated by fewer species that are more adapted to endure warmer and irregular temperature conditions. We designed a long‐term (8 months) mesocosm experiment to explore how ambient water temperature (C: control), induced increased temperature (T: +4°C), and temperature fluctuations (F: ±4°C relative to T) change phytoplankton phenology, taxonomical diversity, and community structure, and how such changes affected zooplankton abundance and composition. Synthesis. Our results show that T and F relative to C significantly decreased phytoplankton diversity. Moreover, there was a clear effect of the temperature treatments (T and F) on phytoplankton size structure that resulted in a significantly lower growth of large species (i.e., large Chlorophyta) compared to C. Decreased diversity and evenness in the T and F treatments pushed the community toward the dominance of only a few phytoplankton taxa (mainly Cyanobacteria and Chlorophyta) that are better adapted to endure warmer and more irregular temperature conditions. The observed shift toward Cyanobacteria dominance may affect trophic energy transfer along the aquatic food web.
Genetic structure among greater white‐fronted goose populations of the Pacific Flyway
Authors: Ely Craig R. , Wilson Robert E. , Talbot Sandra L.
Published: March 2017

An understanding of the genetic structure of populations in the wild is essential for long‐term conservation and stewardship in the face of environmental change. Knowledge of the present‐day distribution of genetic lineages (phylogeography) of a species is especially important for organisms that are exploited or utilize habitats that may be jeopardized by human intervention, including climate change. Here, we describe mitochondrial (mtDNA) and nuclear genetic (microsatellite) diversity among three populations of a migratory bird, the greater white‐fronted goose (Anser albifrons), which breeds discontinuously in western and southwestern Alaska and winters in the Pacific Flyway of North America. Significant genetic structure was evident at both marker types. All three populations were differentiated for mtDNA, whereas microsatellite analysis only differentiated geese from the Cook Inlet Basin. In sexual reproducing species, nonrandom mate selection, when occurring in concert with fine‐scale resource partitioning, can lead to phenotypic and genetic divergence as we observed in our study. If mate selection does not occur at the time of reproduction, which is not uncommon in long‐lived organisms, then mechanisms influencing the true availability of potential mates may be obscured, and the degree of genetic and phenotypic diversity may appear incongruous with presumed patterns of gene flow. Previous investigations revealed population‐specific behavioral, temporal, and spatial mechanisms that likely influence the amount of gene flow measured among greater white‐fronted goose populations. The degree of observed genetic structuring aligns well with our current understanding of population differences pertaining to seasonal movements, social structure, pairing behavior, and resource partitioning.
Water and nitrogen uptake are better associated with resource availability than root biomass
Authors: Kulmatiski Andrew , Adler Peter B. , Stark John M. , Tredennick Andrew T.
Published: March 2017

Plant uptake of soil water and nitrogen can determine plant growth, community composition, and ecosystem functioning. Despite its importance, resource uptake is typically inferred from root biomass distributions rather than measured directly. Using a depth‐controlled, dual‐tracer experiment, here we show that during peak growing season in a sagebrush‐steppe ecosystem, vertical patterns of root biomass, water uptake, and nitrogen uptake are strikingly different from one another. Half of root biomass (0–188 cm) occurred in the top 24 cm of the soil. Half of water uptake occurred in the top 14 cm. Half of nitrogen uptake occurred in the top 79 cm. Shallow water uptake and deep nitrogen uptake were better correlated with water and nitrogen availability than with root biomass, suggesting that root systems foraged independently for different resources. Root biomass has long been used as a proxy measure of plant access to soil resources, but our results suggest that resource availability may be a better predictor of uptake.
Short‐range dispersal maintains a volatile marine metapopulation: the brown algaPostelsia palmaeformis
Authors: Paine Robert T. , Buhle Eric R. , Levin Simon A. , Kareiva Peter
Published: March 2017

The annual brown algaPostelsia palmaeformisis dependent for its survival on short‐distance dispersal (SDD) where it is already established, as well as occasional long‐distance colonization of novel sites. To quantifySDD, we transplantedPostelsiato sites lacking established plants within ≥10 m. The spatial distribution of the first naturally produced sporophyte generation was used to fit dispersal kernels in a hierarchical Bayesian framework. Mean dispersal distance within a year ranged from 0.16 to 0.50 m across sites; 95% of the recruits were within 0.38–1.32 m of the transplant. The fat‐tailed exponential square root kernel was the best among the candidate models at describing offspring density and dispersal. Independent measurements of patch size over two to five generations permitted an evaluation of whether models parameterized by individual‐level data could adequately predict longer‐term persistence and spread at the patch scale. The observed spread rates generally fell within the 95% predictive intervals. Finally,Postelsiawas eliminated from 14 occupied sites that were then followed for ≥27 yr. The probability of invasion when unoccupied declined and the probability of extinction when occupied increased with distance from the nearest propagule source. Sites >10 m from a source were rarely invaded, and one initially densely populated site isolated by 39 m has remainedPostelsia‐free since 1981. In spite of dispersal that is almost entirely within 2 m of the parent, the ability of our models to capture the observed dynamics ofPostelsiaindicates that short‐range dispersal adequately explains the persistent and thrivingPostelsiametapopulation on Tatoosh Island. However, the presence ofPostelsiaover a 2000‐km coastal range with many gaps >1 km makes it clear that rare long‐distance dispersal must be required to explain the geographic range of the species.
Contribution by vertebrates to seed dispersal effectiveness in the Galápagos Islands: a community‐wide approach
Authors: Nogales M. , González‐Castro A. , Rumeu B. , Traveset A. , Vargas P. , Jaramillo P. , Olesen J. M. , Heleno R. H.
Published: March 2017

Seed dispersal and seedling recruitment are crucial phases in the life cycle of all spermatophyte plants. The net contribution of seed dispersers to plant establishment is known as seed dispersal effectiveness (SDE) and is defined as the product of a quantitative (number of seeds dispersed) and a qualitative (probability of recruitment) component. In Galápagos, we studied the direct contribution toSDE(number of seeds dispersed and effect on seedling emergence) provided by the five island groups of frugivores (giant tortoises, lizards, medium‐sized passerine birds, small non‐finch passerine birds, and finches) in the two main habitats in this archipelago: the lowland and the highland zones, and found 16 vertebrate species dispersing 58 plant species. Data on frequency of occurrence of seeds in droppings and number of seeds dispersed per unit area produced contrasting patterns of seed dispersal. Based on the former, giant tortoises and medium‐sized passerines were the most important seed dispersers. However, based on the latter, small non‐finch passerines were the most important dispersers, followed by finches and medium‐sized passerines. The effect of disperser gut passage on seedling emergence varied greatly depending on both the disperser and the plant species. Although the contribution toSDEprovided by different disperser guilds changed across plant species, medium‐sized passerines (e.g., mockingbirds) provided a higher contribution toSDEthan lava lizards in 10 out of 16 plant species analysed, whereas lava lizards provided a higher contribution toSDEthan birds in five plant species. While both the quantitative and qualitative components addressed are important, our data suggests that the former is a better predictor ofSDEin the Galápagos archipelago.