bluuebunny/crossref_metadata_2025 huggingface dataset:
Heat Pipes
Authors: Kosoy Boris
Published: December 2015

Heat pipe is a self‐contained heat transfer device based on the evaporation and condensation of a working fluid, with passive pumping of the condensate back to the evaporator; it has no mechanical moving parts and requires no external power other than the heat that flows through it. Heat pipes ensure good heat spreading capability and geometric flexibility.

Heat pipes are used to perform several important heat transfer and thermal management roles in the chemical and linked industries. Examples include separation of hazardous streams associated with heat source and sink, heat recovery, temperature flattening or isothermalization of processes, temperature control in chemical reactions, and spot cooling.

In its simplest function, the heat pipe possesses the property of extremely high effective thermal conductivity (several hundred times that of metals), for that reason they are sometimes referred to as “thermal superconductors.” As a result, the heat pipe can produce nearly isothermal conditions making an almost ideal heat transfer element. In another form, the heat pipe can provide positive, rapid, and precise control of temperature under conditions that vary with respect to time.
Total Synthesis
Authors: Sierra Miguel A. , de la Torre María C.
Published: December 2015

Total synthesis is the production of a molecule from commercially or readily available chemicals through a series of chemical reactions including bio‐mediated transformations. In the first quarter of the twenty‐first century, most complex molecules are, in principle, accesible through total synthesis. However, often, complex molecules can only be prepared in small amounts of a few milligrams. Therefore, the challenges of total synthesis in the XXIth century is the efficiency by which required amounts of a product can be prepared in the shorter time possible.

In this article, different types of syntheses are discussed. These are divided into four classes: target‐oriented synthesis (TOS), combinatorial synthesis (CS), diversity‐oriented synthesis (DOS), and diverted total synthesis (DTS). The concepts, challenges, and requirements of each class are introduced and relevant examples, from classic to contemporary, including Woodward's synthesis of strychnine, are discussed.
Geophysicochemical model of an ionospheric auroral gyroscope
Authors: Serban Andreea I. , Geicu Ovidiu I. , Serban Florea
Published: December 2015

This study presents a geophysicochemical model of an ionospheric auroral gyroscope. The gyroscopic effect occurs due to the electromagnetic interaction in Earth's polar regions between two types of vertical cavity auroras: the herpolhodic cone (proton cavity aurora), operating in the cusp polar region, and two polhodic cones (an electronic cone and a protonic cone), operating in the aurora region. The ratio between the angular speeds of the herpolhodic and polhodic cones is established by the angle between Earth's rotational axis and the geomagnetic dipole axis. We have developed a theory of the ionospheric auroral gyroscope as a kinematic part of the terrestrial magnetosphere and ionosphere that enables a unified explanation of important macroscopic phenomena that occur at this level. Accordingly, we have explained the oval shape of the polar auroras, Schumann resonances, geomagnetic micropulsation excitation, and the structuring of Earth's areas of radiation. The terrestrial gravitomagnetic field and dark matter are implicated in the initiation and behavior of the auroral ionospheric gyroscope, both of which provide stability and accuracy. Viewed in a wider context, the ionospheric auroral gyroscope theory could offer a way to experimentally investigate dark matter on Earth. Furthermore, it may have a potential value as a predictive tool, providing information about the large earthquakes and Earth's phenomena.
Inferring field‐scale properties of a fractured aquifer from ground surface deformation during a well test
Authors: Schuite Jonathan , Longuevergne Laurent , Bour Olivier , Boudin Frédérick , Durand Stéphane , Lavenant Nicolas
Published: December 2015

Fractured aquifers which bear valuable water resources are often difficult to characterize with classical hydrogeological tools due to their intrinsic heterogeneities. Here we implement ground surface deformation tools (tiltmetry and optical leveling) to monitor groundwater pressure changes induced by a classical hydraulic test at the Ploemeur observatory. By jointly analyzing complementary time constraining data (tilt) and spatially constraining data (vertical displacement), our results strongly suggest that the use of these surface deformation observations allows for estimating storativity and structural properties (dip, root depth, and lateral extension) of a large hydraulically active fracture, in good agreement with previous studies. Hence, we demonstrate that ground surface deformation is a useful addition to traditional hydrogeological techniques and opens possibilities for characterizing important large‐scale properties of fractured aquifers with short‐term well tests as a controlled forcing.
Source analysis of a potential hydraulic‐fracturing‐induced earthquake near Fox Creek, Alberta
Authors: Wang Ruijia , Gu Yu Jeffrey , Schultz Ryan , Kim Ahyi , Atkinson Gail
Published: December 2015

An earthquake with a reported magnitude of 4.4 (ML) was detected on 13 June 2015 in western central Alberta, Canada. This event was the third felt earthquake this year near Fox Creek, a shale gas exploration region. Our results from full moment tensor inversions of regional broadband data show a strong strike‐slip mechanism with near‐vertical fault plane solutions. The decomposition of the moment tensor solution is overwhelmingly double couple, while only a modest (∼20%) contribution is attributed to compensated‐linear‐vector‐dipole. The depth of this earthquake is 3–4 km, near the base of the sedimentary layer, and the moment magnitude (M= 3.9) of this event is considerably smaller than the initial reportedMLvalue. The hypocenter location, depth, and mechanism are favorable to a possible association between this earthquake and hydraulic fracturing operations within the Duvernay shale.
Scaling laws for magnetic reconnection, set by regulation of the electron pressure anisotropy to the firehose threshold
Authors: Ohia O. , Egedal J. , Lukin V. S. , Daughton W. , Le A.
Published: December 2015

Magnetic reconnection in a weakly collisional plasma, such as in the Earth's magnetosphere, is known to be accompanied by electron pressure anisotropy. For reconnection scenarios including moderate guide magnetic field, electrons are magnetized throughout the reconnection region, and the anisotropy drives extended electron current layers. Along these layers, the anisotropy nears the firehose threshold. We describe how the anisotropy stagnates at this threshold by a mechanism that does not involve pitch‐angle mixing. Using previously established anisotropic equations of state and by imposing the marginal firehose condition, scaling laws are obtained for quantities along the current layers as functions of plasma parameters upstream of the reconnection region. The predicted reconnection region quantities include the magnetic field strength, plasma density, and the parallel and perpendicular electron pressures, allowing for a characterization of electron energization solely as a function of the upstream plasma conditions. This characterization is in agreement with simulations and spacecraft observations.
On the role of buoyant flexure in glacier calving
Authors: Wagner Till J. W. , James Timothy D. , Murray Tavi , Vella Dominic
Published: December 2015

Interactions between glaciers and the ocean are key for understanding the dynamics of the cryosphere in the climate system. Here we investigate the role of hydrostatic forces in glacier calving. We develop a mathematical model to account for the elastic deformation of glaciers in response to three effects: (i) marine and lake‐terminating glaciers tend to enter water with a nonzero slope, resulting in upward flexure around the grounding line; (ii) horizontal pressure imbalances at the terminus are known to cause hydrostatic in‐plane stresses and downward acting torque; (iii) submerged ice protrusions at the glacier front may induce additional buoyancy forces that can cause calving. Our model provides theoretical estimates of the importance of each effect and suggests geometric and material conditions under which a given glacier will calve from hydrostatic flexure. We find good agreement with observations. This work sheds light on the intricate processes involved in glacier calving and can be hoped to improve our ability to model and predict future changes in the ice‐climate system.
Sediment supply versus local hydraulic controls on sediment transport and storage in a river with large sediment loads
Authors: Dean David J. , Topping David J. , Schmidt John C. , Griffiths Ronald E. , Sabol Thomas A.
Published: December 2015

The Rio Grande in the Big Bend region of Texas, USA, and Chihuahua and Coahuila, Mexico, undergoes rapid geomorphic changes as a result of its large sediment supply and variable hydrology; thus, it is a useful natural laboratory to investigate the relative importance of flow strength and sediment supply in controlling alluvial channel change. We analyzed a suite of sediment transport and geomorphic data to determine the cumulative influence of different flood types on changing channel form. In this study, physically based analyses suggest that channel change in the Rio Grande is controlled by both changes in flow strength and sediment supply over different spatial and temporal scales. Channel narrowing is primarily caused by substantial deposition of sediment supplied to the Rio Grande during tributary‐sourced flash floods. Tributary floods have large suspended‐sediment concentrations, occur for short durations, and attenuate rapidly downstream in the Rio Grande, depositing much of their sediment in downstream reaches. Long‐duration floods on the mainstem have the capacity to enlarge the Rio Grande, and these floods, released from upstream dams, can either erode or deposit sediment in the Rio Grande depending upon the antecedent in‐channel sediment supply and the magnitude and duration of the flood. Geomorphic and sediment transport analyses show that the locations and rates of sand erosion and deposition during long‐duration floods are most strongly controlled by spatial changes in flow strength, largely through changes in channel slope. However, spatial differences in the in‐channel sediment supply regulate sediment evacuation or accumulation over time in long reaches (greater than a kilometer).
Performance of the Goddard multiscale modeling framework with Goddard ice microphysical schemes
Authors: Chern Jiun‐Dar , Tao Wei‐Kuo , Lang Stephen E. , Matsui Toshihisa , Li J.‐L. F. , Mohr Karen I. , Skofronick‐Jackson Gail M. , Peters‐Lidard Christa D.
Published: December 2015

The multiscale modeling framework (MMF), which replaces traditional cloud parameterizations with cloud‐resolving models (CRMs) within a host atmospheric general circulation model (GCM), has become a new approach for climate modeling. The embedded CRMs make it possible to apply CRM‐based cloud microphysics directly within a GCM. However, most such schemes have never been tested in a global environment for long‐term climate simulation. The benefits of using an MMF to evaluate rigorously and improve microphysics schemes are here demonstrated. Four one‐moment microphysical schemes are implemented into the Goddard MMF and their results validated against three CloudSat/CALIPSO cloud ice products and other satellite data. The new four‐class (cloud ice, snow, graupel, and frozen drops/hail) ice scheme produces a better overall spatial distribution of cloud ice amount, total cloud fractions, net radiation, and total cloud radiative forcing than earlier three‐class ice schemes, with biases within the observational uncertainties. Sensitivity experiments are conducted to examine the impact of recently upgraded microphysical processes on global hydrometeor distributions. Five processes dominate the global distributions of cloud ice and snow amount in long‐term simulations: (1) allowing for ice supersaturation in the saturation adjustment, (2) three additional correction terms in the depositional growth of cloud ice to snow, (3) accounting for cloud ice fall speeds, (4) limiting cloud ice particle size, and (5) new size‐mapping schemes for snow and graupel. Despite the cloud microphysics improvements, systematic errors associated with subgrid processes, cyclic lateral boundaries in the embedded CRMs, and momentum transport remain and will require future improvement.
Modified Stoichiometry in Homogeneous Indium–Zinc Oxide System as Vertically Graded Oxygen Deficiencies by Controlling Redox Reactions
Authors: Tak Young Jun , Rim You Seung , Yoon Doo Hyun , Kim Si Joon , Park Sung Pyo , Lee Heesoo , Kim Woon Gi , Yang Yang , Kim Hyun Jae
Published: December 2015

The present study suggests a way to improve electrical characteristics and stabilities by forming a different stoichiometry in a homogeneous system without using a multiple deposition process. Post treatment by sequential pressure annealing (SPA) of a homogeneous indium–zinc oxide system is carried out to fabricate vertically graded oxygen deficiencies via redox reactions. The SPA treatment consists of several steps. First, hydrogen pressure annealing is performed to chemically expedite the reduction reaction of weak chemical bonds in the overall channel region and thereby make the material highly conducting. Second, oxygen pressure annealing is performed to render the channel a poor conductor by gradually oxidizing the channel from the back to the front. Such SPA‐treated devices have significantly more oxygen deficiencies in the front‐channel region than in the back‐channel region. The stoichiometry of the channel region modified in this manner provided enhanced mobility, a higher on/off ratio, and a decreased threshold voltage shift (under positive and negative bias stresses).
Why Does Industry Not Use Immobilized Transition Metal Complexes as Catalysts?
Authors: Hübner Sandra , de Vries Johannes G. , Farina Vittorio
Published: December 2015

Much effort has gone into the immobilization of homogeneous catalysts based on the idea that in this way the catalysts could be not only separated more easily from the product but also reused several times, thus reducing the cost of the catalyst use. So far none of these immobilized catalysts have been used by industry. In this article we critically review the use of immobilized homogeneous catalysts from the point of view of process development for the pharmaceutical and fine chemical industry. The first and foremost question that needs to be answered is: will immobilizing a homogeneous catalyst really lead to lower costs? The answer is thus far always no. This is caused mostly by the fact that homogeneous catalysts are not stable and thus there is little point in immobilizing them. The second reason is the extra added cost that is incurred in immobilizing the catalysts. Other problems are lower rates, sometimes lower selectivities and metal leaching. Three different areas are discussed. The research on immobilized metathesis catalysts is analyzed in detail; in general the immobilized catalysts do not achieve sufficient turnovers to be interesting for industrial use. Very many publications have appeared on immobilized palladium catalysts that were used for CC bond‐forming reactions, such as Suzuki, Heck or Sonogashira reactions. These catalysts are invariably converted to nanoparticles after the first run. Although these catalysts can be reused, there is no reason to use an expensive support based on immobilized ligands. This also does not protect the product from palladium contamination. Even more effort has gone into the immobilization of homogeneous hydrogenation catalysts. Most of these catalysts suffer from the same problems as the other immobilized catalysts: catalyst deactivation, low turnover numbers, and leaching of the metal. In addition, the heterogenization adds complexity to the system, increasing risk and prolonging process development.

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Preparation and Properties of Polyimides Containing 1,2,3‐Triazole Moieties
Authors: Rukmanikrishnan Balasubramanian , Muthusamy Sarojadevi
Published: December 2015

A new diamine containing 1,2,3‐triazole ring was synthesized by the click reaction in the presence of Cu (I) catalyst. A series of novel polytriazoleimides (PTAIs) were synthesized using the prepared diamine by the conventional two‐step thermal or chemical imidization method with commercially available aromatic dianhydrides. The chemical structure of the monomers and polymers was characterized by Fourier transform Infrared, 1H nuclear magnetic resonance (NMR), and 13C NMR spectral analysis. Solubility of the PTAIs was tested in various organic solvents. The glass transition temperatures of these PTAIs are in the range of 215–254°C. PTAIs exhibit low dielectric constant of 3.04–3.34 at 1 MHz, high thermal stability, and temperature corresponding to 5% (T5%) weight loss is in the range of 442–492°C. The flame retardance values (limiting oxygen index) are in the range of 38.4–40.5. The PTAI films exhibited good mechanical properties with tensile strength of 96.2–98.9 MPa, elongation to break of 9.8–12.6%, and tensile modulus of 2.5–3.1 GPa.
Spin‐Wave Eigenmodes of Dzyaloshinskii Domain Walls
Authors: Borys Pablo , Garcia‐Sanchez Felipe , Kim Joo‐Von , Stamps Robert L.
Published: December 2015

A theory for the spin‐wave eigenmodes of a Dzyaloshinskii domain wall is presented. These walls are Néel‐type domain walls that can appear in perpendicularly magnetized ultrathin ferromagnets in the presence of a sizeable Dzyaloshinskii–Moriya interaction. The mode frequencies for spin waves propagating perpendicular to the domain wall plane are computed using a continuum approximation. In contrast to Bloch‐type walls, it is found that the spin wave potential associated with Dzyaloshinskii domain walls is not reflectionless, which leads to a finite scattering cross‐section for interactions between spin waves and domain walls. A gap produced by the Dzyaloshinskii interaction emerges and band structures arising from periodic wall arrays are discussed.
An anatomy precourse enhances student learning in veterinary anatomy
Authors: McNulty Margaret A. , Stevens‐Sparks Cathryn , Taboada Joseph , Daniel Annie , Lazarus Michelle D.
Published: December 2015

Veterinary anatomy is often a source of trepidation for many students. Currently professional veterinary programs, similar to medical curricula, within the United States have no admission requirements for anatomy as a prerequisite course. The purpose of the current study was to evaluate the impact of a week‐long precourse in veterinary anatomy on both objective student performance and subjective student perceptions of the precourse educational methods. Incoming first year veterinary students in the Louisiana State University School of Veterinary Medicine professional curriculum were asked to participate in a free precourse before the start of the semester, covering the musculoskeletal structures of the canine thoracic limb. Students learned the material either via dissection only, instructor‐led demonstrations only, or a combination of both techniques. Outcome measures included student performance on examinations throughout the first anatomy course of the professional curriculum as compared with those who did not participate in the precourse. This study found that those who participated in the precourse did significantly better on examinations within the professional anatomy course compared with those who did not participate. Notably, this significant improvement was also identified on the examination where both groups were exposed to the material for the first time together, indicating that exposure to a small portion of veterinary anatomy can impact learning of anatomical structures beyond the immediate scope of the material previously learned. Subjective data evaluation indicated that the precourse was well received and students preferred guided learning via demonstrations in addition to dissection as opposed to either method alone. Anat Sci Educ 9: 344–356. © 2015 American Association of Anatomists.
With or without rafts? Alternative views on cell membranes
Authors: Sevcsik Eva , Schütz Gerhard J.
Published: December 2015

The fundamental mechanisms of protein and lipid organization at the plasma membrane have continued to engage researchers for decades. Among proposed models, one idea has been particularly successful which assumes that sterol‐dependent nanoscopic phases of different lipid chain order compartmentalize proteins, thereby modulating protein functionality. This model of membrane rafts has sustainably sparked the fields of membrane biophysics and biology, and shifted membrane lipids into the spotlight of research; by now, rafts have become an integral part of our terminology to describe a variety of cell biological processes. But is the evidence clear enough to continue supporting a theoretical concept which has resisted direct proof by observation for nearly twenty years? In this essay, we revisit findings that gave rise to and substantiated the raft hypothesis, discuss its impact on recent studies, and present alternative mechanisms to account for plasma membrane heterogeneity.
A Derivative of s‐Triazine Modified Reduced Graphene Oxide with the Function of UV‐absorbing
Authors: Liu Tianye , Yan Hongxia , Chen Zhengyan , Xu Peilun , Su Shikun
Published: December 2015

A new s‐triazine derivative modified graphene composite, in which 2,4,6‐tri(2,4‐dihydroxyphenyl)‐1,3,5‐triazine (TDTA) was attached onto reduced graphene oxide (rGO) via the noncovalent functionalization approach, named TDTA/rGO, was reported. And the TDTA was synthesized via a Friedel‐Crafts reaction. FTIR and NMR spectroscopic characterizations were carried out to confirm the synthesis of TDTA. UV‐Vis, XPS and TEM revealed that TDTA molecules were successfully loaded onto graphene sheets by π‐π stacking, and the composite is found to improve greatly the dispersity of rGO in DMF and to be a good UV‐absorber.
Enantioselective Allylic Amination of Morita‐Baylis‐Hillman Acetates Catalyzed by Chiral Thiourea‐Phosphine
Authors: Zhao Xuan , Kang Tianchen , Shen Jie , Sha Feng , Wu Xinyan
Published: December 2015

The enantioselective allylic amination of Morita‐Baylis‐Hillman acetates catalyzed by chiral cyclohexane‐based thiourea‐phosphine catalysts was investigated. In the presence of 20 mol% rosin‐derived thiourea‐phosphine 3j, the chiral amines were obtained in up to 88% yield and up to 85% ee.
Self‐Assembled Oleic Acid Nanoparticle Mediated Inhibition of Mitogen‐Activated Protein Kinase Signaling in Combination with DNA Damage in Cancer Cells
Authors: Palvai Sandeep , More Piyush , Mapara Nikunj , Nagraj Jyothi , Chowdhury Rajdeep , Basu Sudipta
Published: December 2015

Mitogen‐activated protein kinase (MAPK) signaling has been dysregulated in different types of cancers. However, targeting MAPK signaling with small molecules leads to severe toxic side effects to the patients as well as manifestation of drug resistance. To address these, we have developed 120 nm sized self‐assembled, biocompatible, biodegradable oleic acid nanoparticles (OA‐NPs) which can simultaneously contain AZD6244 (MAPK inhibitor) and cisplatin (DNA damaging drug). These OA‐NPs released AZD6244 and cisplatin in increased amount in pH 5.5 compared to pH 7.4 in a slow and sustained manner over 4 days with excellent stability at 4 °C for 2 months in water and in blood circulation mimic for 6 days. Moreover, these OA‐NPs showed much improved in vitro cytotoxicity in cervical cancer (HeLa) and triple negative breast cancer (MDA‐MB‐231) cells at 48 h and in hepatocellular carcinoma (Hep3B) and cisplatin‐resistant hepatocellular carcinoma (Hep3B‐R) cells at 24 h. In HeLa cells, these OA‐NPs induced apoptosis through inhibiting MAPK signaling and damaging DNA after being internalized through macropinocytosis and homed into the acidic lysosomal compartments. These OA‐NPs have the potential to be translated into the clinic for targeting multiple oncogenic signaling pathways and damaging DNA concurrently for augmented efficacy, reduced toxicity, and overcoming drug resistance in next‐generation cancer treatment.
Incorporation of hafnium (IV) into KTP framework from phosphate‐fluoride fluxes
Authors: Zatovsky Igor V. , Slobodyanik Nikolay S. , Ivanenko V. I. , Oseledchik Yu. S. , Letsenko V. Yu. , Ushchapivska Tetiana I.
Published: December 2015

Solid solutions KTi1‐XHfXOPO4 (х = 0.008 – 0.107) possessing the KTiOPO4 structure, have been synthesized in molten system K2O‐P2O5‐TiO2‐HfF4. The crystal growth experiment of Hf‐doped KTP crystal has been reported. The X‐ray powder diffraction data and chemical analysis are also presented. It has been shown that KTiOPO4 crystal structure slightly changes when Hf incorporates into the framework. Transmission/absorption spectra of KTi0.974Hf0.026OPO4 crystals have been recorded. The incorporation of Hf ions shifts the optical absorption edge in the UV‐visible spectrum towards the long‐wavelength region with absorption near 387 nm.
Limitation of seedling growth by potassium and magnesium supply for two ectomycorrhizal tree species of a Central African rain forest and its implication for their recruitment
Authors: Neba Godlove Ambe , Newbery David McClintock , Chuyong George Bindeh
Published: December 2015

In the ectomycorrhizal caesalpiniaceous groves of southern Korup National Park, the dominant tree species, Microberlinia bisulcata, displays very poor in situ recruitment compared with its codominant, Tetraberlinia bifoliolata. The reported ex situ experiment tested whether availabilities of soil potassium and magnesium play a role. Seedlings of the two species received applications of K and Mg fertilizer in potted native soil in a local shade house, and their responses in terms of growth and nutrient concentrations were recorded over 2 years. Amended soil concentrations were also determined. Microberlinia responded strongly and positively in its growth to Mg, but less to K; Tetraberlinia responded weakly to both. Added Mg led to strongly increased Mg concentration for Microberlinia while added K changed that concentration only slightly; Tetraberlinia strongly increased its concentration of K with added K, but only somewhat its Mg concentration with added Mg. Additions of Mg and K had small but important antagonistic effects. Microberlinia is Mg‐demanding and apparently Mg‐limited in Korup soil; Tetraberlinia, whilst K‐demanding, appeared not to be K‐limited (for growth). Added K enhanced plant P concentrations of both species. Extra applied Mg may also be alleviating soil aluminum toxicity, and hence improving growth indirectly and especially to the benefit of Microberlinia. Mg appears to be essential for Microberlinia seedling growth and its low soil availability in grove soils at Korup may be an important contributing factor to its poor recruitment. Microberlinia is highly shade‐intolerant and strongly light‐responding, whilst Tetraberlinia is more shade‐tolerant and moderately light‐responding, which affords an interesting contrast with respect to their differing responses to Mg supply. The study revealed novel aspects of functional traits and likely niche‐partitioning among ectomycorrhizal caesalps in African rain forests. Identifying the direct and interacting indirect effects of essential elements on tropical tree seedling growth presents a considerable challenge due the complex nexus of causes involved.
Paleodistribution modeling suggests glacial refugia in Scandinavia and out‐of‐Tibet range expansion of the Arctic fox
Authors: Fuentes‐Hurtado Marcelo , Hof Anouschka R. , Jansson Roland
Published: December 2015

Quaternary glacial cycles have shaped the geographic distributions and evolution of numerous species in the Arctic. AncientDNAsuggests that the Arctic fox went extinct in Europe at the end of the Pleistocene and that Scandinavia was subsequently recolonized from Siberia, indicating inability to track its habitat through space as climate changed. Using ecological niche modeling, we found that climatically suitable conditions for Arctic fox were found in Scandinavia both during the last glacial maximum (LGM) and the mid‐Holocene. Our results are supported by fossil occurrences from the last glacial. Furthermore, the model projection for theLGM, validated with fossil records, suggested an approximate distance of 2000 km between suitable Arctic conditions and the Tibetan Plateau well within the dispersal distance of the species, supporting the recently proposed hypothesis of range expansion from an origin on the Tibetan Plateau to the rest of Eurasia. The fact that the Arctic fox disappeared from Scandinavia despite suitable conditions suggests that extant populations may be more sensitive to climate change than previously thought.
Seyferth–Gilbert Homologation as a Route to 18F‐Labeled Building Blocks: Preparation of Radiofluor­inated Phenylacetylenes and Their Application in PET Chemistry
Authors: Krapf Philipp , Richarz Raphael , Urusova Elizaveta A. , Neumaier Bernd , Zlatopolskiy Boris D.
Published: December 2015

A convenient method for the preparation of hitherto unknown ([18F]fluorophenyl)acetylenes ([18F]FPAs) using the Seyferth–Gilbert homologation is reported. The novel building blocks were efficiently prepared from easily accessible [18F]fluorobenzaldehydes by using the Bestmann–Ohira reagent. High radiochemical yields and excellent radiochemical purities were achieved within only 20 min of reaction time; 2‐ and 4‐[18F]FPAs were applied to prepare radiofluorinated heterocycles by using different cycloaddition and cross‐coupling reactions. Additionally, these building blocks were used to prepare three novel PET tracers. Thus, an artificial radiofluorinated protected amino acid [18F]10, a COX‐2‐specific ligand [18F]14, and a PSMA‐selective inhibitor [18F]16 were obtained in high radiochemical yields.
Sugar‐Based Organocatalyst for the Diastereoselective Desymmetrization of Dibenzylideneacetones
Authors: Pinheiro Danielle L. J. , Batista Gabriel M. F. , Gonçalves Jaqueline R. , Duarte Talita N. , Amarante Giovanni W.
Published: December 2015

A Brønsted acid catalyzed highly regio‐ and diastereoselective desymmetrization of dibenzylideneacetones in the presence of azlactones is described (only 1,4 addition, > 20:1 dr). A novel organocatalyst based on D‐galactose was synthesized and applied in this reaction. In terms of product, a new C–C σ‐bond and two stereogenic centers are created, one of which is quaternary. The relative stereochemistry was assigned by comparison of both chiral HPLC traces and 13C NMR spectroscopic data as being 1,2‐anti. One of the final Michael‐type adducts could be converted into an N‐protected α‐functionalized amino acid in good yield and with no loss of diastereoselectivity.
Introverted Phosphorus‐Au Cavitands for Catalytic Use
Authors: Schramm Michael P. , Kanaura Mao , Ito Kouhei , Ide Masataka , Iwasawa Tetsuo
Published: December 2015

A preparative synthesis of an inwardly directed phosphoramidite‐Au complex is described and a description of some of its catalytic performance. The molecular structure was determined by crystallographic analysis, which disclosed that the phosphoramidite ligand points “out” and places the complexed Au “in”. We investigated its catalytic activities and found that the inwardly directed Au is surrounded by three inert walls that provide new opportunities for supramolecular catalysis and study of reactive intermediates.
Ultrasensitive analysis of glucose in serum by capillary electrophoresis with LIF detection in combination with signal amplification strategies and on‐column enzymatic assay
Authors: Guan Yueqing , Zhou Guobin
Published: December 2015

A highly specific and sensitive method for glucose quantification in human serum samples based on on‐column enzymatic assay is described. In this method, the head of the capillary was used as a nanoliter‐microreactor, the diluted samples spiked with a novel fluorogenic reagent named 2‐[6‐(4′‐amino) phenoxy‐3H‐xanthen‐3‐on‐9‐yl] benzoic acid (APF), and the mixed enzyme solutions of glucose oxidase (GOx) and horseradish peroxidase (HRP), were individually injected into the capillary. Hydrogen peroxide (H2O2) generated in situ by catalytic reaction between GOx and glucose, activates APF in the presence of HRP to form a highly fluorescent product, which was electrophoretically separated from the unreacted APF and detected by the LIF detector. The proposed method allowed the determination of glucose down to 10 nM in real samples, with RSD values lower than 3.5%, which also has the potential for measurements of multicomponents in many other systems including measurement of α‐glucosidase activity and screening for its inhibitors.
Microbial community shifts of anaerobic sludge in response to nitrate and nitrite in simultaneous denitrification and methanogenesis systems
Authors: Li Zhen‐Zhen , Shi Xian‐Yang
Published: December 2015

Anaerobic sludge was exposed to an increasing gradient of nitrite/nitrate using acetate as the carbon source in order to explore its community shifts in response to nitrate and nitrite in simultaneous denitrification and methanogenesis (SDM) systems. Amplified ribosomal DNA restriction digestion analysis (ARDRA), quantitative polymerase chain reaction (qPCR) and statistical analysis of non‐metric multidimensional scaling (NMS) was used in this study. The methanogenesis was inhibited by nitrate transiently and recovered soon, whereas when it was inhibited by 200 and 400 mg N/L nitrite, it recovered after a longer time. Dominant archaea in anaerobic sludge dosed with 0‐200 mg N/L nitrite/nitrate was Methanosarcinaceae and changed to Methanosaetaceae when nitrate/nitrite was increased to 400 mg N/L. Changes of methanogenic archaea communities were influenced by carbon source limitation rather than nitrate/nitrite inhibition. The results provided biochemical and molecular biological insight into the SDM system, which could be helpful for anaerobic reactor design and performance in the SDM system. © 2015 American Institute of Chemical Engineers Environ Prog, 35: 661–668, 2016
The practice of DEM stream burning revisited
Authors: Lindsay John B.
Published: December 2015

Stream burning is a common flow enforcement technique used to correct surface drainage patterns derived from digital elevation models (DEM). The technique involves adjusting the elevations of grid cells that are coincident with the features of a vector hydrography layer. This paper focuses on the problematic issues with common stream burning practices, particularly the topological errors resulting from the mismatched scales of the hydrography and DEM data sets. A novel alternative stream burning method is described and tested using five DEMs of varying resolutions (1 to 30 arc‐seconds) for an extensive area of southwestern Ontario, Canada. This TopologicalBreachBurn method uses total upstream channel length (TUCL) to prune the vector hydrography layer to a level of detail that matches the raster DEM grid resolution. Network pruning reduces the occurrence of erroneous stream piracy caused by the rasterization of multiple stream links to the same DEM grid cell. The algorithm also restricts flow within individual stream reaches, further reducing erroneous stream piracy. In situations where two vector stream features occupy the same grid cell, the new tool ensures that the larger stream, designated by higher TUCL, is given priority. TUCL‐based priority minimizes the impact of the topological errors that occur during the stream rasterization process on modeled regional drainage patterns. The test data demonstrated that TopologicalBreachBurn produces highly accurate and scale‐insensitive drainage patterns and watershed boundaries. The drainage divides of four large watersheds within the study region that were delineated from the TopologicalBreachBurn‐processed DEMs were found to be highly accurate when compared with the official watershed boundaries, even at the coarsest grid resolutions, with Kappa index of agreement values ranging from 0.952 to 0.921. The corresponding Kappa coefficient values for a traditional stream burning method (FillBurn) ranged from 0.953 to 0.490, demonstrating a significant decrease in mapping accuracy at coarser DEM grid resolutions. Copyright © 2015 John Wiley & Sons, Ltd.
Spatial learning and neurogenesis: Effects of cessation of wheel running and survival of novel neurons by engagement in cognitive tasks
Authors: Motta‐Teixeira Lívia Clemente , Takada Silvia Honda , Machado‐Nils Aline Vilar , Nogueira Maria Inês , Xavier Gilberto Fernando
Published: December 2015

Physical exercise stimulates cell proliferation in the adult dentate gyrus and facilitates acquisition and/or retention of hippocampal‐dependent tasks. It is established that regular physical exercise improves cognitive performance. However, it is unclear for how long these benefits last after its interruption. Independent groups of rats received both free access to either unlocked (EXE Treatment) or locked (No‐EXE Treatment) running wheels for 7 days, and daily injections of bromodeoxyuridine (BrdU) in the last 3 days. After a time delay period of either 1, 3, or 6 weeks without training, the animals were tested in the Morris water maze (MWM) either in a working memory task dependent on hippocampal function (MWM‐HD) or in a visible platform searching task, independent on hippocampal function (MWM‐NH). Data confirmed that exposure of rats to 7 days of spontaneous wheel running increases cell proliferation and neurogenesis. In contrast, neurogenesis was not accompanied by significant improvements of performance in the working memory version of the MWM. Longer time delays between the end of exercise and the beginning of cognitive training in the MWM resulted in lower cell survival; that is, the number of novel surviving mature neurons was decreased when this delay was 6 weeks as compared with when it was 1 week. In addition, data showed that while exposure to the MWM‐HD working memory task substantially increased survival of novel neurons, exposure to the MWM‐NH task did not, thus indicating that survival of novel dentate gyrus neurons depends on the engagement of this brain region in performance of cognitive tasks. © 2015 Wiley Periodicals, Inc.
Marital Therapy: Beyond Evaluation
Authors: Harvey Les
Published: December 2015

This discussion on the use of evaluation research by policy makers was stimulated by Hartin's article Evaluating Marital Therapy (this issue). Problems arise because evaluation research and accountability reporting are often confused, and because evaluation researchers tend to communicate with each other rather than with policy makers and program managers.
Family Therapy, Group Work and Psychiatry—Working Under the Influence
Authors: Munt Glenn
Published: December 2015

When people are admitted to a psychiatric hospital they are degraded in status by the admission process — a ceremony supported by structures built into the hospital/treatment system. This paper explores some aspects of this process and proposes systemic group work as one way of redressing the balance for process. Regrading of status begins when patients discover the important contribution they have made to their own recovery.

The development and application of systemic group work is traced, and Jantsch's concept of co‐evolution is invoked as one useful way of understanding the process. Co‐evolutionary ideas are also important in understanding the processes which occur in the context of the hospital ward and the wider systems into which influence extends.
Topically Administered Clindamycin in the Treatment of Acne Vulgaris and Other Dermatologic Disorders
Authors: Rosen Theodore , Waisman Margaret
Published: December 2015

Clindamycin is a macrolide antibiotic that has been used orally and topically in the treatment of acne vulgaris. Unfortunately, oral administration is associated with pseudomembranous colitis in up to 10% of patients; consequently, it is no longer a generally accepted form of acne therapy. Topical application is an effective, safer alternative. Topical formulations may be extemporaneously prepared or purchased as a pre‐mixed hydroalcoholic solution. Adverse effects associated with topical preparations are few and mostly minor. Topical clindamycin is also used in the treatment of erythrasma, rosacea, periorificial facial dermatitis, and folliculitis.
Myasthenia Gravis: Signs, Symptoms, Diagnosis, Immunology, and Current Therapy
Authors: Scheife Richard T. , Hills John R. , Munsat Theodore L.
Published: December 2015

Myasthenia gravis is a neuromuscular disease that presents clinically as fluctuating weakness of one or more skeletal muscle groups. Weakness becomes more severe with exercise and improves with rest. The disease is caused by an autoimmune reaction at or near the post‐synaptic nicotinic acetylcholine receptor. The results of this immune reaction are the lytic destruction of the post‐synaptic membrane and a reduction in the number of acetylcholine receptors.

Myasthenia gravis can be diagnosed by repetitive exercise of the involved muscles, administration of edrophonium (Tensilon), electrophysiologic testing, or demonstration of anti‐acetylcholine receptor antibodies.

When the myasthenic weakness is mild or limited to the extraocular muscles, it may be treated with acetylcholinesterase inhibitors. When the weakness is more severe and/or more generalized, immunotherapy is most often indicated. Prednisone or prednisone plus thymectomy is the most frequently used form of immunotherapy. Azathioprine, 6‐mercaptopurine, plasmapheresis, or gamma globulin injections are other immunotherapeutic options that may be useful in selected patients.

A large number of drugs may precipitate or exacerbate myasthenic weakness.
Netilmicin Sulfate: A Comparative Evaluation of Antimicrobial Activity, Pharmacokinetics, Adverse Reactions and Clinical Efficacy
Authors: Craig William A. , Gudmundsson Sigurdur , Reich Richard M.
Published: December 2015

Netilmicin, the 1‐N‐ethyl derivative of sisomicin, is a new aminoglycoside antibiotic that was recently marketed in the United States. Its role in therapeutics is not yet established. The pharmacokinetic profile of netilmicin is very similar to that of gentamicin. Its antimicrobial spectrum and clinical efficacy is similar to that of gentamicin, tobramycin and amikacin. It is less active in vitro against Pseudomonas aeruginosa than gentamicin and tobramycin, but in clinical trials the efficacy of netilmicin against this organism has been similar to other aminoglycosides. Netilmicin is active against some gentamicin and tobramycin‐resistant strains of gram‐negative bacilli, particularly those harboring adenylating and phosphorylating enzymes. Most of these strains are sensitive to amikacin as well, and amikacin is also active against most netilmicin‐resistant strains of these bacteria. Therefore, amikacin remains the aminoglycoside of choice against gentamicin tobramycin and netilmicin‐resistant gram‐negative bacilli. In comparison to other currently available aminoglycosides, a lower frequency of nephrotoxicity and ototoxicity has been observed in laboratory animals given netilmicin. This has not been unequivocally demonstrated in humans. The frequency of nephrotoxicity in humans has been similar to that of other aminoglycosides. The frequency of ototoxicity associated with netilmicin in humans has been low but not significantly less than with other aminoglycosides, except in one trial. If further studies document a significantly lower frequency of ototoxicity with netilmicin, it may become the aminoglycoside of choice for patients with significant risk factors for ototoxicity, such as advanced age, renal impairment, concomitant ototoxic drug therapy and prolonged aminoglycoside administration.
Dissolution of Struvite Calculi by Hemiacidrin Solution
Authors: Massaro Frank J. , Weiner Bruce , Sant Grannum R. , Meares Edwin M.
Published: December 2015

Struvite calculi result from urinary tract infections secondary to urease‐producing bacteria. To prevent recurrent infection and stone formation complete removal of struvite calculi is recommended. Two illustrative reports of patients with renal struvite calculi are presented in which 10% hemiacidrin (Renacidin) irrigation was instituted for stone dissolution. After surgical removal of the calculi a nephrostomy tube was placed in the renal pelvis. With confirmation of residual struvite calculi, 10% hemiacidrin irrigation was initiated. Urine cultures, electrolytes and nephrotomograms were performed and adverse effects monitored. Using strict aseptic technique and appropriate precautions, hemiacidrin irrigation safely dissolves struvite calculi.
Evaluation of Bupropion Hydrochloride: The First of a New Class of Atypical Antidepressants
Authors: Preskorn Sheldon H. , Othmer Sieglinde C.
Published: December 2015

Bupropion hydrochloride is a new antidepressant that differs clinically and pharmacologically from the tricyclic antidepressants and the monoamine oxidase inhibitors. Pharmacokinetically, bupropion is an intermediate‐lived drug with a half‐life of about 12 hours. Its antidepressant activity in man has been demonstrated in double‐blind, placebo and active drug‐controlled studies. Onset of antidepressant action occurs in one to three weeks. Bupropion has a greater effect on the neuronal reuptake of dopamine than of other biogenic amines. At a recommended dose of 450–600 mg/day, the side effect profile of bupropion also distinguishes it from other antidepressants. It does not bind to cholinergic receptors in vitro at clinically relevant concentrations and does not produce appreciable autonomic side effects. The exception is dry mouth, which is reported in 13% of patients. The mechanism underlying this effect is unclear. Bupropion is devoid of cardiovascular effects (e.g., impaired intracardiac conduction, reduced myocardial contractility, decreased peripheral resistance, orthostatic hypotension) in both human and animal studies. The drug is nonsedating and antagonizes the effects of commonly used sedatives, such as alcohol and diazepam. It does not produce weight gain. In susceptible patients, activating effects can occur. Given this profile, bupropion should be less toxic than conventional antidepressants when taken in overdoses; however overdose experience with the drug is limited.
Liquid and Solid Potassium Chloride: Bioavailability and Safety
Authors: Skoutakis Vasilios A. , Acchiardo Sergio R. , Wojciechowski Norbert J. , Carter Charles A.
Published: December 2015

Studies have suggested that microencapsulated preparations of potassium chloride may pose less risk to the upper gastrointestinal mucosa than the currently available wax‐matrix preparations. Based on our own clinical experience and data available from the literature, we have concluded that (1) liquid and slow‐release preparations of potassium chloride are safe and effective when used appropriately and (2) at present there is no conclusive evidence to suggest that lesions of the upper gastrointestinal tract are more prevalent with one slow‐release preparation than with another.