bluuebunny/crossref_metadata_2025 huggingface dataset:
Crustal structure across the Costa Rican Volcanic Arc
Authors: Hayes Jorden L. , Holbrook W. Steven , Lizarralde Dan , van Avendonk Harm J. A. , Bullock Andrew D. , Mora Mauricio , Harder Steven , Alvarado Guillermo E. , Ramírez Carlos
Published: February 2013

Island arcs are proposed to be essential building blocks for the crustal growth of continents; however, island arcs and continents are fundamentally different in bulk composition: mafic and felsic, respectively. The substrate upon which arcs are built (oceanic crust versus large igneous province) may have a strong influence on crustal genesis. We present results from an across‐arc wide‐angle seismic survey of the Costa Rican volcanic front which test the hypothesis that juvenile continental crust is actively forming at this location. Travel‐time tomography constrains velocities in the upper arc to a depth of ~15 km where average velocities are <6.5 km/s. The upper 5 km of crust is constrained by velocities between 4.0 and 5.5 km/s, which likely represent sediments, volcaniclastics, flows, and small intrusions. Between 5 and 15 km depth, velocities increase slowly from 5.5 to 6.5 km/s. Crustal thickness and lower crustal velocities are roughly constrained by reflections from an inferred crust‐mantle transition zone. Crustal thickness beneath the volcanic front in Costa Rica is ~40 km with best‐fit average lower‐crustal velocities between 6.8 and 7.1 km/s. Overall, velocities across the arc in central Costa Rica are at the high‐velocity extreme of bulk continental crust velocities and are lower than modern island arc velocities, suggesting that continental compositions are created at this location. These data suggest that preexisting thick crust of the Caribbean Large Igneous Province has a measurable effect on bulk composition. This thickened arc crust may be a density filter for mafic material and thereby support differentiation toward continental compositions.
Irrigation in California's Central Valley strengthens the southwestern U.S. water cycle
Authors: Lo Min‐Hui , Famiglietti James S.
Published: February 2013

Characterizing climatological and hydrological responses to agricultural irrigation continues to be an important challenge to understanding the full impact of water management on the Earth's environment and hydrological cycle. In this study, we use a global climate model, combined with realistic estimates of regional agricultural water use, to simulate the local and remote impacts of irrigation in California's Central Valley. We demonstrate a clear mechanism that the resulting increase in evapotranspiration and water vapor export significantly impacts the atmospheric circulation in the southwestern United States, including strengthening the regional hydrological cycle. We also identify that irrigation in the Central Valley initiates a previously unknown, anthropogenic loop in the regional hydrological cycle, in which summer precipitation is increased by 15%, causing a corresponding increase in Colorado River streamflow of ~30%. Ultimately, some of this additional streamflow is returned to California via managed diversions through the Colorado River aqueduct and the All‐American Canal.
Revised UV absorption spectra, ozone depletion potentials, and global warming potentials for the ozone‐depleting substances CF2Br2, CF2ClBr, and CF2BrCF2Br
Authors: Papanastasiou Dimitrios K. , Carlon Nabilah Rontu , Neuman J. Andrew , Fleming Eric L. , Jackman Charles H. , Burkholder James B.
Published: February 2013

The contribution of Halons, bromine‐containing haloalkanes, to stratospheric ozone depletion is highly dependent on their atmospheric lifetime, which is primarily determined by UV photolysis. In this work, UV absorption cross‐sections of the ozone‐depleting substances CF2Br2 (Halon‐1202), CF2ClBr (Halon‐1211), and CF2BrCF2Br (Halon‐2402) were measured between 300 and 350 nm over the temperature range 210–296 K using cavity ring‐down spectroscopy. Rayleigh scattering cross‐sections were also determined and utilized in the cross‐section determination. Spectra parameterizations are presented and 2‐D atmospheric model calculations were used to determine global annually averaged atmospheric lifetimes of 2.52, 16.4, and 28.3 years, ozone depletion potentials (ODPs) of 1.95, 8.1, and 18.4, global warming potentials (GWPs) of 175, 1940, and 2270 (100‐year time horizon), and associated uncertainties for CF2Br2, CF2ClBr, and CF2BrCF2Br, respectively. The revised lifetimes, ODPs, and GWPs differ from values currently reported in international assessments to evaluate ozone recovery and climate change.
First investigations of IO, BrO, and NO2 summer atmospheric levels at a coastal East Antarctic site using mode‐locked cavity enhanced absorption spectroscopy
Authors: Grilli Roberto , Legrand Michel , Kukui Alexandre , Méjean Guillaume , Preunkert Suzanne , Romanini Daniele
Published: February 2013

IO, BrO, and NO2 were measured for the first time at Dumont d'Urville (East Antarctic coast) during summer 2011/2012 by using a near‐UV‐Visible laser spectrometer based on mode‐locked cavity‐enhanced absorption spectroscopy. IO mixing ratios ranged from the 2σ detection limit (0.04 pptv) up to 0.15 pptv. BrO remained close or below the detection limit (2 pptv) of the instrument. Daily averaged NO2 values ranged between the detection limit (10 pptv) and 60 pptv being far higher than levels of a few pptv commonly observed in the remote marine boundary layer. Data are discussed and compared with those available for another coastal Antarctic station (Halley, West Antarctica). It is shown that the oxidative capacity of the atmospheric boundary layer at coastal Antarctic sites is quite different in nature from West to East Antarctica, with the halogen chemistry being promoted at West and the OH chemistry at East.
Using synthetic tracers as a proxy for summertime PM2.5 air quality over the Northeastern United States in physical climate models
Authors: Fang Yuanyuan , Fiore Arlene M. , Lamarque Jean‐François , Horowitz Larry W. , Lin Meiyun
Published: February 2013

Fine particulate matter (PM2.5) is a criteria pollutant. Its sensitivity to meteorology implies its distribution will likely change with climate shifts. Limited availability of global climate models with full chemistry complicates efforts to assess rigorously the uncertainties in the PM2.5 response to a warming climate. We evaluate the potential for PM2.5 distributions in a chemistry‐climate model under current‐day and warmer climate conditions over the Northeastern United States to be represented by a Synthetic Aerosol tracer (SAt). The SAt implemented into the Geophysical Fluid Dynamics Laboratory chemistry‐climate model (AM3) follows the protocol of a recent multimodel community effort (HTAP), with CO emissions, 25‐day chemical lifetime, and wet deposition rate of sulfate. Over the Northeastern United States, the summer daily time series of SAt correlates strongly with that of PM2.5, with similar cumulative density functions under both present and future climate conditions. With a linear regression model derived from PM2.5 and SAt in the current‐day simulation, we reconstruct both the current‐day and future PM2.5 daily time series from the simulated SAt. This reconstruction captures the summer mean PM2.5, the incidence of days above the 24‐h mean PM2.5 NAAQS, and PM2.5 responses to climate change. This reconstruction also works over other polluted Northern Hemispheric regions and in spring. Our proof‐of‐concept study demonstrates that simple tracers can be developed to mimic PM2.5, including its response to climate change, as an easy‐to‐implement and low‐cost addition to physical climate models that should help air quality managers to reap the benefits of climate models that have no chemistry.
Magnetite deformation mechanism maps for better prediction of strain partitioning
Authors: Till J. L. , Moskowitz Bruce
Published: February 2013

A meta‐analysis of existing experimental deformation data for magnetite and other spinel‐structured ferrites reveals that previously published flow laws are inadequate to describe the general deformation behavior of magnetite. Using updated rate equations for oxygen diffusion in magnetite, we present new flow laws that closely predict creep rates similar to those found in deformation experiments and that can be used to predict strain partitioning between cubic Fe oxides and other phases in the Earth's crust. New deformation mechanism maps for magnetite have been constructed as functions of temperature and grain size. Using the revised creep parameters, estimates of strain partitioning between magnetite, ilmenite, and plagioclase indicate that concentrated zones of Fe‐Ti oxides in oceanic crust near slow‐spreading ridges could accommodate significant amounts of strain at moderate temperatures and may contribute to aseismic creep along spreading‐segment faults.
Detection of tropical cyclone track changes from the ECMWF ensemble prediction system
Authors: Tsai Hsiao‐Chung , Elsberry Russell L.
Published: February 2013

A cluster analysis of the 51 member European Center for Medium‐range Weather Forecasts ensemble forecast tracks of existing tropical storms from the THORPEX Interactive Grand Global Ensemble archive is utilized to detect multiple track solutions, and weighted‐mean vector motion (WMVM) tracks are calculated for the ensemble tracks and for the individual track clusters. When three track clusters were present, larger errors occurred in the corresponding deterministic model forecast. Reliability of the European Center for Medium‐range Weather Forecasts ensemble forecast tracks when two distinct clusters exist is examined in terms of the hit rates when the cluster with the larger number of members is selected. A larger hit rate is achieved if track clusters with at least 70%, 80%, or 90% of the members are selected. In these situations, the forecaster can select the WMVM tracks for those clusters and have confidence that a more accurate track than the overall WMVM track will generally be predicted.
Neuropsychiatric symptoms in Alzheimer's disease are related to functional connectivity alterations in the salience network
Authors: Balthazar Marcio L. F. , Pereira Fabrício R. S. , Lopes Tátila M. , da Silva Elvis L. , Coan Ana Carolina , Campos Brunno M. , Duncan Niall W. , Stella Florindo , Northoff Georg , Damasceno Benito P. , Cendes Fernando
Published: February 2013

Neuropsychiatric syndromes are highly prevalent in Alzheimer's disease (AD), but their neurobiology is not completely understood. New methods in functional magnetic resonance imaging, such as intrinsic functional connectivity or “resting‐state” analysis, may help to clarify this issue. Using such approaches, alterations in the default‐mode and salience networks (SNs) have been described in Alzheimer's, although their relationship with specific symptoms remains unclear. We therefore carried out resting‐state functional connectivity analysis with 20 patients with mild to moderate AD, and correlated their scores on neuropsychiatric inventory syndromes (apathy, hyperactivity, affective syndrome, and psychosis) with maps of connectivity in the default mode network and SN. In addition, we compared network connectivity in these patients with that in 17 healthy elderly control subjects. All analyses were controlled for gray matter density and other potential confounds. Alzheimer's patients showed increased functional connectivity within the SN compared with controls (right anterior cingulate cortex and left medial frontal gyrus), along with reduced functional connectivity in the default‐mode network (bilateral precuneus). A correlation between increased connectivity in anterior cingulate cortex and right insula areas of the SN and hyperactivity syndrome (agitation, irritability, aberrant motor behavior, euphoria, and disinhibition) was found. These findings demonstrate an association between specific network changes in AD and particular neuropsychiatric symptom types. This underlines the potential clinical significance of resting state alterations in future diagnosis and therapy. Hum Brain Mapp 35:1237–1246, 2014. © 2013 Wiley Periodicals, Inc.
DTI correlates of distinct cognitive impairments in Parkinson's disease
Authors: Zheng Zhong , Shemmassian Shirag , Wijekoon Christopher , Kim Won , Bookheimer Susan Y. , Pouratian Nader
Published: February 2013

The spectrum of cognitive symptoms in Parkinson's disease (PD) can span various domains, including executive function, language, attention, memory, and visuospatial skills. These symptoms may be attributable to the degradation of projection fibers associated with the underlying neurodegenerative process. The primary purpose of this study is to find microstructural correlates of impairments across these cognitive domains in PD using diffusion tensor imaging (DTI). Sixteen patients with PD with comprehensive neuropsychological evaluation and DTI data were retrospectively studied. Fractional anisotropy (FA) and mean diffusivity (MD) were assessed using regions‐of‐interest (ROI) analysis and confirmed with a voxel‐based approach. Executive function directly correlated with FA and inversely correlated with MD in mostly frontal white matter tracts, especially the anterior limb of the internal capsule and genu of the corpus callosum. Likewise, language and attentional performance demonstrated correlations with DTI parameters in the frontal regions, but the attention domain additionally recruited regions widespread throughout the brain, with the most significant correlation identified in cingulate gyrus (cingulum). Lastly, memory impairment mainly involved MD alterations within the fornix. No significant correlations were found between visuospatial skills and DTI measures. Despite some overlap, unique patterns of white matter diffusivity underlie impairments in distinct cognitive domains in patients with PD. DTI combined with neurocognitive tests may be a valuable biomarker for identifying cognitive impairments in PD. Hum Brain Mapp 35:1325–1333, 2014. © 2013 Wiley Periodicals, Inc.
New Lignans from the Aerial Parts of Rudbeckia laciniata
Authors: Lee Seung Young , Woo Kyeong Wan , Kim Chung Sub , Lee Dong Ung , Lee Kang Ro
Published: February 2013

Three new furofuran lignans, (+)‐4,4′‐O‐diangeloylpinoresinol (1), (+)‐4,4′‐O‐diangeloylmedioresinol (2), and (+)‐4,4′‐O‐diangeloylsyringaresinol (3), together with the known compound (+)‐syringaresinol, were isolated from the MeOH extract of Rudbeckia laciniata. The structure elucidation of these compounds were based on 1D‐ and 2D‐NMR, and HR‐ESI‐MS data. The additional structural evidence was obtained from alkaline hydrolysis of the compounds.
Synthesis and Metal Complexes of Thiourea Ligands Containing Carbohydrate‐Derived Substituents
Authors: Sternberg Michelle , Rust Jörg , Lehmann Christian W. , Mohr Fabian
Published: February 2013

Two glucose‐derived thiourea derivatives,2aand2b, were prepared by addition of the corresponding amino sugars to a solution of 4‐nitrobenzoyl isothiocyanate (Scheme 1). The thioureas were isolated as colorless solids in good yields and were fully characterized by NMR spectroscopy, optical rotation, elemental analysis, and also by single‐crystal X‐ray diffraction. Attempts to obtain CuIIand NiIIbis(chelate) complexes with these thioureas failed. However, the C(1)‐protected thiourea derivative2areacted with orthopalladated acetato‐bridged dimers to afford the corresponding monomeric PdIIcomplexes3and4(Scheme 2). In these compounds, the thiourea coordinates to the metal as monoanionic O,S chelate ligand, which was confirmed by X‐ray crystallography.
Further Explorations into the Synthesis of Dehydro‐Hedione®
Authors: Winter Béat , Chapuis Christian , Brauchli Robert , de Saint Laumer Jean‐Yves
Published: February 2013

Dehydrohedione (DHH) 1 may be obtained in 20% overall yield by a Reformatsky reaction with enone methyl ether 3b, followed by acidic workup of the crude reaction mixture. Alternatively, epoxidation (3‐chloroperbenzoic acid, CH2Cl2, 84% yield) of the tertiary allyl alcohol derivative 4 affords a 1 : 2 mixture of 8a and 8b. The latter epoxy ester 8b may also be obtained stereoselectively either from 4 (tBuO2H, [Mo(CO)6], 1,2‐dichloroethane, 70°, 62% yield; or tBuO2H, [VO(acac)2], decane, 20°, 92% yield), or from 5 (AcOMe, LiN(SiMe3)2, THF, −78°, 84–87%). BF3⋅Et2O‐Catalyzed cascade rearrangement and OH elimination of 8a afford selectively DHH 1 in 88% yield. The cis disposition of the side chains of the weakly odoriferous hedione‐like analogues 2b and 2c was maintained by means of either an epoxy or a cyclopropane moiety.
FUNCTIONAL ANALYSIS AND TREATMENT OF DIURNAL BRUXISM
Authors: Lang Russell , Davenport Katy , Britt Courtney , Ninci Jennifer , Garner Jennifer , Moore Melissa
Published: February 2013

An analogue functional analysis identified attention as a function for a 5‐year‐old boy's bruxism (teeth grinding). Functional communication training resulted in a reduction of bruxism and an increase in alternative mands for attention. Results were maintained 3 weeks following the intervention.
Role of ATF7-TAF12 interactions in the vitamin D response hypersensitivity of osteoclast precursors in Paget's disease
Authors: Teramachi Jumpei , Hiruma Yuko , Ishizuka Seiichi , Ishizuka Hisako , Brown Jacques P , Michou Laëtitia , Cao Huiling , Galson Deborah L , Subler Mark A , Zhou Hua , Dempster David W , Windle Jolene J , Roodman G David , Kurihara Noriyoshi
Published: February 2013

Osteoclast (OCL) precursors from many Paget's disease (PD) patients express measles virus nucleocapsid protein (MVNP) and are hypersensitive to 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3; also know as calcitriol). The increased 1,25-(OH)2D3 sensitivity is mediated by transcription initiation factor TFIID subunit 12 (TAF12), a coactivator of the vitamin D receptor (VDR), which is present at much higher levels in MVNP-expressing OCL precursors than normals. These results suggest that TAF12 plays an important role in the abnormal OCL activity in PD. However, the molecular mechanisms underlying both 1,25-(OH)2D3's effects on OCL formation and the contribution of TAF12 to these effects in both normals and PD patients are unclear. Inhibition of TAF12 with a specific TAF12 antisense construct decreased OCL formation and OCL precursors' sensitivity to 1,25-(OH)2D3 in PD patient bone marrow samples. Further, OCL precursors from transgenic mice in which TAF12 expression was targeted to the OCL lineage (tartrate-resistant acid phosphatase [TRAP]-TAF12 mice), formed OCLs at very low levels of 1,25-(OH)2D3, although the OCLs failed to exhibit other hallmarks of PD OCLs, including receptor activator of NF-κB ligand (RANKL) hypersensitivity and hypermultinucleation. Chromatin immunoprecipitation (ChIP) analysis of OCL precursors using an anti-TAF12 antibody demonstrated that TAF12 binds the 24-hydroxylase (CYP24A1) promoter, which contains two functional vitamin D response elements (VDREs), in the presence of 1,25-(OH)2D3. Because TAF12 directly interacts with the cyclic adenosine monophosphate–dependent activating transcription factor 7 (ATF7) and potentiates ATF7-induced transcriptional activation of ATF7-driven genes in other cell types, we determined whether TAF12 is a functional partner of ATF7 in OCL precursors. Immunoprecipitation of lysates from either wild-type (WT) or MVNP-expressing OCL with an anti-TAF12 antibody, followed by blotting with an anti-ATF7 antibody, or vice versa, showed that TAF12 and ATF7 physically interact in OCLs. Knockdown of ATF7 in MVNP-expressing cells decreased cytochrome P450, family 24, subfamily A, polypeptide 1 (CYP24A1) induction by 1,25-(OH)2D3, as well as TAF12 binding to the CYP24A1 promoter. These results show that ATF7 interacts with TAF12 and contributes to the hypersensitivity of OCL precursors to 1,25-(OH)2D3 in PD.
Is retention of zoledronic acid onto bone different in multiple myeloma and breast cancer patients with bone metastasis?
Authors: Søe Kent , Plesner Torben , Jakobsen Erik H , Hansen Charlotte T , Jørgensen Henrik B , Delaissé Jean-Marie
Published: February 2013

Zoledronic acid (Zol) is used to treat bone disease in both multiple myeloma (MM) and breast cancer patients with bone metastasis (BC). However, bones of MM and BC patients show a difference in retention of the bisphosphonate used for bone scintigraphy. Therefore, we hypothesized that disease-specific factors may differently influence Zol retention in MM and BC patients. We tested this hypothesis in an investigator initiated phase II clinical trial in which we compared the whole-body retention (WBrt) of Zol in a cohort of 30 multiple myeloma (MM) and 30 breast cancer (BC) (20 Zol naive and 40 with six or more previous administrations). On average, 62% of the administered Zol was retained in the skeleton of both MM and BC patients and independently of the number of treatments. WBrt of Zol did not correlate with cross-linked C-telopeptide (CTX) levels, but linear regression analyses showed that WBrt of Zol correlated with bone-specific alkaline phosphatase (bALP) levels in BC (p = 0.001), and with CTX/bALP in Zol naive MM patients (p = 0.012). Especially in BC patients, WBrt correlated with age (p = 0.014) independently of kidney function. In MM patients WBrt was found to primarily correlate with the extent of bone disease (p = 0.028). Multivariate linear regression analyses of the entire cohort pointed out that WBrt of Zol was best predicted by age (p < 0.000), osseous lesions (p < 0.001), and the preceding Zol dosing (p < 0.005) (r2 = 0.97). Comparing bone scintigrams with CT/X-ray images showed a poor correlation between sites of active bone disease and binding of scintigraphy bisphosphonate in 36% of MM patients and in 13% of BC patients. We conclude that WBrt of Zol is primarily determined by two non-disease related factors and only one disease related, but that there may be differences in retention or drug delivery at individual sites of bone disease between MM and BC patients. In order to find the optimal dosing of Zol, these observations should be taken into account.
Pharmacogenetics of Allopurinol—Making an Old Drug Safer
Authors: Lam May P. S. , Yeung Chi K. , Cheung Bernard M. Y.
Published: February 2013

Allopurinol is a drug that has been used for decades to lower serum urate levels in patients with gout or chronic renal failure and in cancer patients undergoing chemotherapy at risk of tumor lysis syndrome. Patients may develop cutaneous hypersensitivity reactions, ranging from mild rashes to potentially fatal severe cutaneous adverse reactions (SCARs) namely drug hypersensitivity syndrome, Stevens–Johnson syndrome (SJS), and toxic epidermal necrolysis (TEN). Recent studies have demonstrated the association between human leukocyte antigen (HLA) B*58:01 allele and allopurinol‐induced SCARs, which might explain ethnic differences in their incidences. Genotyping is now required before starting abacavir and carbamazepine so as to identify individuals susceptible to SJS. However, no genetic screening is advocated before commencement of allopurinol. The lack of availability of a rapid and inexpensive screening test for the HLA‐B*58:01 allele is one of the obstacles to such screening. Development of a test that is quick, accurate, and cost‐effective is warranted.
New constraints on Greenland ice sheet dynamics during the last glacial cycle: Evidence from the Uummannaq ice stream system
Authors: Roberts David H. , Rea Brice R. , Lane Tim P. , Schnabel Christoph , Rodés Angel
Published: February 2013

This paper presents the first assessment of the Uummannaq ice stream system (UISS) in West Greenland. The UISS drained ~6% of the Greenland ice sheet (GrIS) at the Last Glacial Maximum (LGM). The onset of the UISS is a function of a convergent network of fjords which feed a geologically controlled trough system running offshore to the shelf break. Mapping, cosmogenic radiogenic nuclide (CRN) dating, and model output reveal that glacially scoured surfaces up to 1266 m above sea level (asl) in fjord‐head areas were produced by warm‐based ice moving offshore during the LGM, with the elevation of warm‐based ice dropping westwards to ~700 m asl as the ice stream trunk zone developed. Marginal plateaux with allochthonous blockfields suggest that warm‐based ice produced till and erratics up to ~1200 m asl, but CRN ages and weathering pits suggest this was pre‐LGM, with only cold‐based ice operating during the LGM. Deglaciation began on the outer shelf at ~14.8 cal. kyrs B.P., with Ubekendt Ejland becoming ice free at ~12.4 ka. The UISS then collapsed with over 100 km of retreat by ~11.4 ka–10.8 cal. kyrs B.P., a rapid and complex response to bathymetric deepening, trough widening, and sea‐level rise coinciding with rapidly increasing air temperatures and solar radiation, but which occurred prior to ocean warming at ~8.4 cal. kyrs B.P. Local fjord constriction temporarily stabilized the unzipped UISS margins at the start of the Holocene before ice retreat inland of the current margin at ~8.7 ka.
Impacts of disturbance on the terrestrial carbon budget of North America
Authors: Kasischke Eric S. , Amiro Brian D. , Barger Nichole N. , French Nancy H. F. , Goetz Scott J. , Grosse Guido , Harmon Mark E. , Hicke Jeffrey A. , Liu Shuguang , Masek Jeffrey G.
Published: February 2013

Because it is an important regulator of terrestrial carbon cycling in North America, extensive research on natural and human disturbances has been carried out as part of the North American Carbon Program and the CarboNA project. A synthesis of various components of this research was carried out, and the results are presented in the papers contained in this special section. While the synthesis primarily focused on the impacts of fire, insects/disease, and harvesting on terrestrial carbon cycling in forests, several groups focused on impacts of disturbance on woody encroachment in western U.S. dry lands and on soil carbon present in northern high‐latitude regions. Here, we present a summary of the results from these papers, along with the findings and recommendations from the disturbance synthesis.
The Degree‐Diameter Problem for Claw‐Free Graphs and Hypergraphs
Authors: Dankelmann Peter , Vetrík Tomáš
Published: February 2013

We study the degree‐diameter problem for claw‐free graphs and 2‐regular hypergraphs. Let be the largest order of a claw‐free graph of maximum degree Δ and diameter D. We show that , where , for any D and any even . So for claw‐free graphs, the well‐known Moore bound can be strengthened considerably. We further show that for with (mod 4). We also give an upper bound on the order of ‐free graphs of given maximum degree and diameter for . We prove similar results for the hypergraph version of the degree‐diameter problem. The hypergraph Moore bound states that the order of a hypergraph of maximum degree Δ, rank k, and diameter D is at most . For 2‐regular hypergraph of rank and any diameter D, we improve this bound to , where . Our construction of claw‐free graphs of diameter 2 yields a similar result for hypergraphs of diameter 2, degree 2, and any even rank .
Synthesis of selectively labeled histidine and its methylderivatives with deuterium, tritium, and carbon‐14
Authors: Šamonina‐Kosicka J. , Kańska M.
Published: February 2013

Isotopologues of l‐histidine and its N‐methylderivatives labeled with deuterium and tritium at the 5‐position in the imidazole ring were obtained using the isotope exchange method. The deuterium‐labeled isotopologues [5‐2H]‐l‐histidine, [5‐2H]‐Nτ‐methyl‐l‐histidine, [5‐2H]‐Nπ‐methyl‐l‐histidine, and [2,5‐2H2]‐l‐histidine were synthesized by isotope exchange method carried out in a fully deuterated medium with. The same reaction conditions were applied to synthesize [5‐3H]‐Nτ‐methyl‐l‐histidine, [5‐3H]‐Nπ‐methyl‐l‐histidine, and [5‐3H]‐l‐histidine with specific activity of 2.0, 5.0, and 2.6 MBq/mmol, respectively. The Nπ‐[methyl‐14C]‐histamine was obtained with specific activity of 0.23 MBq/mmol in a one‐step reaction by the direct methylation of histamine by [14C]iodomethane.
Carbon‐14 radiosynthesis of the benzofuran derivative and β‐amyloid plaque neuroimaging positron emission tomography radioligand AZD4694
Authors: Sandell Johan
Published: February 2013

In support of a metabolite study, the β‐amyloid plaque neuroimaging positron‐emission tomography radioligand AZD4694 was labeled with carbon‐14 in 10 radiosynthetic steps starting from radiolabeled carbon dioxide. [14C]AZD4694 was labeled in the benzofuran heterocycle with a specific activity of 2.1 GBq/mmol and with a radiochemical purity of >99%. The described synthesis constitutes a general method to carbon‐14‐labeled substituted benzofurans.
Probing crystallographic orientation of a single GaN nanotube using polarized Raman imaging
Authors: Patsha Avinash , Sahoo Prasana , Dhara S. , Amirthapandian S. , Tyagi A. K.
Published: February 2013

We report the study of crystallographic orientation of a highly anisotropic square‐shaped single wurtzite GaN nanotube (NT) probed by polarized Raman imaging. The polarization‐dependent Raman intensities are collected in two mutually orthogonal directions with respect to the NT long axis. Variation in intensities of symmetry allowed A1(LO) mode of GaN with two different polarization directions reveals the possible crystalline orientations in the NT. The polarized Raman spectral imaging illustrates the fact of inhomogeneous crystalline orientations along the edges of the NT facets owing to its finite wall thickness. The deviation of polarization selection rule for GaN is attributed to the geometrical anisotropy of the NT. Electron microscopic structural data confirms the spectral imaging analyses. Copyright © 2013 John Wiley & Sons, Ltd.
Strategic Governance Lessons from History for West African Microfinance Cooperatives
Authors: Périlleux Anaïs
Published: February 2013

Cooperatives actively pursuing financial inclusion in West Africa could potentially benefit from a closer look at the historical Raiffeisen model, which may help them provide long‐term loans in rural areas through specific strategic changes.
Over‐expression, secretion, biochemical characterisation, and structure analysis of Bacillus subtilis aminopeptidase
Authors: Gao Xinxing , Cui Wenjing , Tian Yaping , Zhou Zhemin
Published: February 2013

Background

Aminopeptidases have great application in the food industry. Current research on the expression of aminopeptidases mainly focuses on the Escherichia coli expression system. However, the application of recombinant E. coli in the food industry is restricted due to its pathogenicity and low secretory efficiency, which should be concerned in the industrial production of aminopeptidases.

Results

The gene of aminopeptidase from Bacillus subtilis Zj016 (BSAP) was identified. Over‐expression and secretion of BSAP were achieved in a B. subtilis expression system with the signal peptide of itself. The yield researched 52 ± 1.9 U mL−1, which was 18 times that of the wild‐type microbe. The purified enzyme was stable at pH 7.5–9.0 and below 60°C, and was inhibited by several metal ions except appropriate Co2+. BSAP was most active toward p‐nitroaniline derivatives of Leu, Arg and Lys. Homology modelling and structure analysis showed that there was a flexible protease‐associated domain in the predicted structure of BSAP.

Conclusions

The study presented a simple procedure for over‐expression and purification of BSAP. The substrate specificity and structure information were indicated based on the characterisation and homology modelling. This will be useful for further research of aminopeptidases not only from an academic standpoint but also from an applied point of view. © 2013 Society of Chemical Industry
Trauma Associated With Civil Conflict and Posttraumatic Stress Disorder: Evidence From the Northern Ireland Study of Health and Stress
Authors: Bunting Brendan P. , Ferry Finola R. , Murphy Samuel D. , O'Neill Siobhan M. , Bolton David
Published: February 2013

The authors provide epidemiological estimates of trauma, posttraumatic stress disorder (PTSD), and associated mental disorders in Northern Ireland (NI) with a focus on the impact of civil conflict using data from the NI Study of Health and Stress (NISHS), a representative epidemiological survey of adults in NI. Overall 60.6% had a lifetime traumatic event, and 39.0% experienced a presumed conflict‐related event. Men were significantly more likely to experience any traumatic event and most conflict‐related event types (p < .05). The lifetime and 12‐month prevalence of PTSD were 8.8% and 5.1%, respectively. Furthermore, the lifetime prevalence of any mental disorder among men and women who experienced a conflict‐related trauma (46.0% and 55.9%, respectively) was significantly higher than the prevalence among men and women who did not experience this type of traumatic event (27.2% and 31.1%, respectively). Given the public health burden posed by PTSD and additional impact of conflict, specific attention must be paid to the policy, service, and clinical challenge of delivering evidence‐based treatments in the wake of a tumultuous period of conflict.
Comparison of scholarly impact among surgical specialties: An examination of 2429 academic surgeons
Authors: Svider Peter F. , Pashkova Anna A. , Choudhry Zaid , Agarwal Nitin , Kovalerchik Olga , Baredes Soly , Liu James K. , Eloy Jean Anderson
Published: February 2013

Objectives/Hypothesis

The h‐index, a bibliometric indicator that objectively characterizes the impact of an author's scholarship, is an effective tool that may be considered by academic departments for decisions related to hiring and faculty advancement. Our objective was to characterize the scholarly productivity of academic surgeons from different specialties relative to otolaryngologists.

Study Design

Analysis of a bibliometric database.

Methods

The h‐indices of 2,429 faculty members within surgical specialties at 20 randomly selected academic institutions were calculated using the Scopus database and were examined to determine relationship with academic rank and comparison among surgical subspecialties.

Results

The h‐index statistically increased with academic rank. Mean h‐indices were as follows: assistant professor, 4.37 (range, 2.73–6.69); associate professor, 8.70 (6.53–11.02); professor, 16.44 (13.39–20.45); and chairperson, 20.79 (14.81–27.89). Mean increase between academic rank was 5.47, with the largest increase between the levels of associate professor and professor. Further examination demonstrated statistically significant increases through all academic ranks for most, but not all, individual specialties. Urologists, general surgeons, and neurosurgeons had the highest mean h‐indices.

Conclusions

h‐indices among the different surgical specialties vary and are potentially impacted by the number of practitioners as well as research emphasis within a field. The mean h‐index of academic otolaryngologists falls in the lower values for academic surgeons. Because this metric varies among different fields, it is most relevant for comparison when examining values within a field. H‐indices reliably increase with increasing academic rank through professor and offer a quantifiable and objective alternative to other metrics when evaluating faculty members for academic advancement.
Hollow Multilayer Microcapsules for pH‐/Thermally Responsive Drug Delivery using Aliphatic Poly(urethane‐amine) as Smart Component
Authors: Shi Jun , Du Chao , Shi Jin , Wang Yaming , Cao Shaokui
Published: February 2013

Hollow multilayer microcapsules made of aliphatic poly(urethane‐amine) (PUA) and sodium poly(styrene sulfonate) (PSS), templated on PSS‐doped CaCO3 particles, are prepared for pH‐/thermally responsive drug delivery. The electrostatic interaction and hydrogen bonding under weak‐acid conditions between aliphatic PUA and PSS contribute to the formation of multilayer microcapsules. Scanning electron microscopy (SEM) results demonstrate an obvious variation of the hollow multilayer microcapsules in response to changes in temperature and pH value. Drug‐release behaviors using DOX as a model drug demonstrate that the drug release increases on decreasing the pH value because of the interaction weakness between aliphatic PUA and PSS in acidic conditions. Moreover, the drug release is higher at 55 °C than that at 37 °C for the sake of the shrinkage of aliphatic PUA above its lower critical solution temperature (LCST).

magnified image
Nonpharmacological enhancement of cognitive function in Parkinson's disease: A systematic review
Authors: Hindle John V. , Petrelli Annette , Clare Linda , Kalbe Elke
Published: February 2013

Cognitive decline and dementia are frequent in patients with Parkinson's disease (PD). The evidence for nonpharmacological therapies in Alzheimer's disease and other dementias has been studied systematically, but the evidence is unclear for their efficacy in cognition and dementia in PD. An international collaboration produced a comprehensive, systematic review of the effectiveness and of nonpharmacological and noninvasive therapies in cognitively intact, cognitively impaired, and PD dementia groups. The interventions included cognitive rehabilitation, physical rehabilitation, exercise, and brain stimulation techniques but excluded invasive treatments, such as surgery and deep brain stimulation. The potential biases and evidence levels for controlled trials (CTs) were analyzed based on Cochrane and National Institute for Health and Clinical Excellence criteria. After exclusions, 18 studies were reviewed, including 5 studies of cognitive training, 4 of exercise and physical therapies, 4 of combined cognitive and physical interventions, and 5 of brain stimulation techniques. The methodology, study populations, interventions, outcomes, control groups, analyses, results, limitations, biases, and evidence levels of all reviewed studies were described. There were 9 CTs, including 6 randomized CTs (RCTs). Although 5 trials showed positive results, only 1 study of cognitive training achieved evidence grading of 1+ with a low risk of bias. There were no studies on PD dementia. Current research on nonpharmacological therapies for cognitive dysfunction and dementia in PD is very limited in quantity and quality. There is an urgent need for rigorous RCTs of nonpharmacological treatments for cognitive impairment and dementia in PD. © 2013 Movement Disorder Society
The role of leech water sampling in choice of prophylactic antibiotics in medical leech therapy
Authors: Wilmer Amanda , Slater Karen , Yip Judy , Carr Nicholas , Grant Jennifer
Published: February 2013

Medical leech therapy (MLT) with Hirudo medicinalis is well established as a treatment for venous congestion of tissue flaps, grafts, and replants. Unfortunately, this treatment is associated with surgical site infections with bacterial species, most commonly Aeromonas hydrophila, which is an obligate symbiot of H. medicinalis. For this reason, prophylactic antibiotics are recommended in the setting of MLT. After culturing Aeromonashydrophila resistant to ciprofloxacin from a tissue specimen from a patient with a failed replant of three digits post‐MLT, we performed environmental surveillance cultures and antibiotic susceptibility testing on water collected from leech tanks. This surveillance was performed twice weekly for 2.5 months. Fourteen surveillance cultures demonstrated 21 isolates of Aeromonas species, 71.4% of which were ciprofloxacin susceptible. All isolates were sulfamethoxazole‐trimethoprim (SXT) susceptible. The prophylactic antibiotic regimen of choice for leech therapy at our institution is SXT, with culture of tank water to refine antimicrobial choice if necessary. This study demonstrates the importance of regular surveillance to detect resistant Aeromonas species in medical leeches; however optimal practice has not been established. © 2013 Wiley Periodicals, Inc. Microsurgery, 2013.
Global gray and white matter metabolic changes after simian immunodeficiency virus infection in CD8‐depleted rhesus macaques: proton MRS imaging at 3 T
Authors: Wu William E. , Tal Assaf , Kirov Ivan I. , Rusinek Henry , Charytonowicz Daniel , Babb James S. , Ratai Eva‐Maria , Gilberto Gonzalez R. , Gonen Oded
Published: February 2013

To test the hypotheses that global decreased neuro‐axonal integrity reflected by decreased N‐acetylaspartate (NAA) and increased glial activation reflected by an elevation in its marker, the myo‐inositol (mI), present in a CD8‐depleted rhesus macaque model of HIV‐associated neurocognitive disorders. To this end, we performed quantitative MRI and 16 × 16 × 4 multivoxel proton MRS imaging (TE/TR = 33/1400 ms) in five macaques pre‐ and 4–6 weeks post‐simian immunodeficiency virus infection. Absolute NAA, creatine, choline (Cho), and mI concentrations, gray and white matter (GM and WM) and cerebrospinal fluid fractions were obtained. Global GM and WM concentrations were estimated from 224 voxels (at 0.125 cm3 spatial resolution over ~35% of the brain) using linear regression. Pre‐ to post‐infection global WM NAA declined 8%: 6.6 ± 0.4 to 6.0 ± 0.5 mM (p = 0.05); GM Cho declined 20%: 1.3 ± 0.2 to 1.0 ± 0.1 mM (p < 0.003); global mI increased 11%: 5.7 ± 0.4 to 6.5 ± 0.5 mM (p < 0.03). Global GM and WM brain volume fraction changes were statistically insignificant. These metabolic changes are consistent with global WM (axonal) injury and glial activation, and suggest a possible GM host immune response. Copyright © 2013 John Wiley & Sons, Ltd.
Genetic predisposition to an adverse lipid profile limits the improvement in total cholesterol in response to weight loss
Authors: Walker Celia G. , Holzapfel Christina , Loos Ruth J.F. , Mander Adrian P. , Klopp Norman , Illig Thomas , Caterson Ian D. , Hauner Hans , Jebb Susan A.
Published: February 2013

Objective

Overweight and obesity are associated with a dyslipidaemia which can be improved by weight loss. Whether genetic predisposition to an adverse lipid profile modifies such beneficial effects of weight loss on lipid levels in overweight and obese individuals was examined.

Design and methods

White European participants (n = 374) who completed a 12‐month weight loss trial were genotyped for 36 lipid‐associated single nucleotide polymorphisms (SNPs), previously identified in genome‐wide association studies (GWAS). Genetic predisposition scores (GPSs) were calculated for four lipid traits by summing the number of risk alleles (RA) for each participant. The associations of each GPS with four lipid traits were assessed at baseline, and with lipid changes in response to weight change after 12 months.

Results

At baseline, the trait‐specific GPSs were associated with 0.11 ± 0.04 mM higher total cholesterol/RA (P = 0.004), 0.05 ± 0.02 mM higher low density lipoprotein cholesterol/RA (P = 0.005), 0.03 ± 0.007 mM lower high density lipoprotein cholesterol/RA (P = 0.00002) and 0.04 ± 0.01 mM higher triglyceride/RA (P = 0.00002). After the intervention, weight loss was associated with improvements in all lipids (P < 0.01). GPS attenuated the weight loss‐associated reduction in TC so those with a higher GPS had less improvement (interaction = 0.01 ± 0.005 mM/GPS/kg weight loss, P = 0.003). A similar pattern was observed for LDLC (interaction = 0.004 ± 0.002 mM/GPS/kg weight loss, P = 0.07). There was no evidence of a GPS‐modifying effect for change in HDLC or TG.

Conclusion

Genetic predisposition is an important determinant of lipid levels and appears to limit the improvement in TC and to some extent LDLC levels, but not in other plasma lipids, in response to weight loss. © 2013 American Institute of Chemical Engineers AIChE J, 2013
Effect of rolling temperature on microstructure and tensile properties of polypropylene
Authors: Murata Takuya , Qiu Jianhui , Wu Xueli
Published: February 2013

Rolling process was carried out with extruded polypropylene as crystalline polymer at various rolling temperatures, and the rolling characteristics, cross‐section morphologies, and tensile properties were investigated. The rolling characteristics were evaluated by springback and dimensional change. The springback increased with increasing rolling temperature. The increment of length was larger than that of width because of the influence of uniaxial drawing by rotation of the rollers. Uniform morphologies were observed at a rolling ratio of 70% and a rolling temperature of 23°C. In contrast, molecular orientation near the surface was higher compared with the inner part when rolled at 70°C. Furthermore, micro spherulitic structures were observed near the surface where recrystallization occurred because of the rising temperature on the specimen surface by friction. Therefore, different morphologies appeared near the surface and in the inner part. Tensile strength was obtained for the rolling direction when rolled at 110°C lower than at other rolling temperatures. It was likely that the molecular orientation was decreased by increasing the springback when rolled at high temperature. POLYM. ENG. SCI., 53:2573–2581, 2013. ©2013 Society of Plastics Engineers
G. C. Lichtenberg, der Physiker: Altes und Neues
Authors: Brix P.
Published: February 2013

Die mathematischen Zeichen + und – für die elektrische Ladung hat er (Bild 1) eingeführt [4]. Er erfand das Elektroschweißen. Von ihm stammen die Idee des Faradaykäfigs und die Grundlagen moderner Blitzschutztechnik: Wenn ich in einem Lande wohnte, wo die Gewitter so tobten, wie etwa in Carolina, so baute ich mir einen Käfig von vergoldeten Stangen über mein Haus. — Wir wissen von der Natur des Blitzes nur folgende beide Sätze mit Gewißheit: 1. Er ist etwas Elektrisches, 2. wenn er eine ununterbrochene Strecke Metall antrifft, so folgt er ihr, leitet man also diese nach der Erde, so geht er auch dahin. … Es ist schon vollkommen hinreichend, wenn nur die Schornsteine, die Firsten und alle hervorstehende Ecken der Gebäude mit zusammenhängenden Streifen von Blei oder Kupfer belegt, und [diese geerdet] werden. Die hohen und spitzen Stangen können ganz wegbleiben.
Das Modell des inflationären Universums
Authors: Börner G. , Straumann N.
Published: February 2013

„Ich habe mit viel Interesse Deinen Vortrag gegen die Hegelei gelesen, welche bei uns Theoretikern das Don Quijotesche Element ausmacht oder soll ich sagen, den Verführer? Wo dies Übel oder Laster aber gründlich fehlt, ist der hoffnungslose Philister auf dem Plan … ”︁ (Aus einem Brief von Einstein an Born)
Bedeutung und Zukunft von Hochenergiebeschleunigern
Authors: Telegdi V. L.
Published: February 2013

Die Zielsetzungen und gegenwärtigen Tätigkeiten von ICFA, dem International Committee for Future Accelerators, werden als Einleitung kurz erörtert. Das ursprüngliche Ziel, der Bau eines Superbeschleunigers (VBA) auf weltweiter Basis, erscheint zur Zeit etwas unrealistisch angesichts der ambitiösen, sich bis in die neunziger Jahre erstreckenden Baupläne der verschiedenen Regionen. Diese Pläne werden relativ ausführlich vorgestellt.