bluuebunny/crossref_metadata_2025 huggingface dataset:
Predictive Factors for Extrathyroidal Extension of Papillary Thyroid Carcinoma Based on Preoperative Sonography
Authors: Lee Chang Yoon , Kim Soo Jin , Ko Kyung Ran , Chung Ki-Wook , Lee Joo-Hyuk
Published: January 2014

Objectives

The purpose of this study was to evaluate the diagnostic performance and predictive factors of extrathyroidal extension of papillary thyroid carcinoma based on preoperative sonography.

Methods

Preoperative sonography was performed for 568 patients who underwent surgery for papillary thyroid cancer between May 2009 and December 2010. Patients' T stages based on preoperative sonography were compared with their T stages based on pathologic examination, and we statistically analyzed the discriminatory performance of sonography. Among the 568 patients enrolled in this study, we selected 320 patients in whom extrathyroidal extension was suspected on sonography. We analyzed several predictive factors for extrathyroidal extension.

Results

Two hundred seventy‐five of the 568 patients were proven to have pathologic extrathyroidal extension of papillary thyroid cancer after surgery (75.9% diagnostic accuracy, 83.3% sensitivity, 68.9% specificity, 71.6% positive predictive value, and 81.5% negative predictive value). Of 320 patients with sonographically suspected extrathyroidal extension, a larger lesion size (P < .001) and a higher lymph node stage on sonography (P = .004) were the best predictors of extrathyroidal extension among the features that we measured. There were no significant differences in terms of the lesion site or thyroid parenchymal background echogenicity. Thyroid capsular protrusion had a higher predictive value than the abutting ratio (P = .001). However, increasing the abutting ratio enabled the prediction of extrathyroidal extension on sonography (P = .009).

Conclusions

Preoperative sonography is a helpful tool for predicting pathologic extrathyroidal extension of papillary thyroid cancer. In particular, clinicians should focus on the lesion size, nodal stage, and abutment or capsular protrusion of the lesion while performing sonography because these are the most useful predictive factors for extrathyroidal extension.
Sonographic Detection of Thyroid Pyramidal Lobes Before Thyroid Surgery
Authors: Kim Dong Wook , Ha Tae Kwun , Park Ha Kyoung , Kang Taewoo
Published: January 2014

Objectives

This study aimed to assess the rate of preoperative sonographic detection of thyroid pyramidal lobes with subsequent surgical findings as the reference standard.

Methods

From January 2013 to March 2013, a single radiologist prospectively performed thyroid sonography to detect thyroid pyramidal lobes in consecutive patients who were scheduled for thyroid surgery on the same day. The location, anteroposterior and transverse diameters, length, and location of the upper end of each thyroid pyramidal lobe and its separation or contiguity with the main thyroid gland were investigated by thyroid sonography and surgery.

Results

The types of thyroid surgery included total thyroidectomy (n = 85), subtotal thyroidectomy (n = 4), and hemithyroidectomy (n = 43). The surgical incidence of thyroid pyramidal lobes was 59.8% (79 of 132), and the sensitivity, specificity, positive and negative predictive values, and accuracy of sonography for detection of thyroid pyramidal lobes were 81.0%, 79.2%, 85.3%, 73.7%, and 80.3%, respectively. The mean values for the anteroposterior diameter, transverse diameter, and length of the 79 thyroid pyramidal lobes at surgery were 2.2, 6.2, and 26.5 mm, respectively, but these measurements did not show statistically significant correlations with the sonographic detection rate of thyroid pyramidal lobes.

Conclusions

Our study indicates that thyroid sonography may be helpful for identifying the presence and location of thyroid pyramidal lobes.
Orientation of the Uterine Fundus in Reference to the Longitudinal Axis of the Body
Authors: Sakhel Khaled , Sinkovskaya Elena , Horton Sharon , Beydoun Hind , Chauhan Suneet P. , Abuhamad Alfred Z.
Published: January 2014

Objectives

The aim of this pilot study was to measure the angle of rotation of the uterus at the fundus from horizontal using 3‐dimensional sonography in women presenting for annual gynecologic examinations.

Methods

A total of 51 patients participated in the study. All patients underwent transvaginal sonography, and 3‐dimensional volumes were acquired. The cervicouterine angle and the angle of rotation at the fundus were measured.

Results

The uteri were noted to be anteverted in 64.7%, retroverted in 25.5%, and euverted in 9.8%. They were noted to be pointing toward the right side of the pelvis in 49.0%, to the left side in 39.2%, and at the midline in 11.8%. The median cervicouterine angle was 122° (interquartile range [IQR], 105°–137°). The median angle of rotation at the fundus away from horizontal in either a clockwise or counterclockwise direction on the transverse B‐plane was 10.4° (IQR, 7.1°–19.0°), with a maximal angle of 43°, and on the coronal C‐plane, it was 10.0° (IQR, 3.0°–20.0°), with a maximal angle of 43°. Noneuverted uteri were more likely to be rotated at the fundus.

Conclusions

Our study reveals that, contrary to traditional thinking, the uterus can be rotated at the fundus in relation to the body (z‐axis) along the longitudinal axis of the cervical canal.
Use of Cerclage in Triplet Pregnancies With an Asymptomatic Short Cervix
Authors: Young Christopher M. , Stanisic Tatiana , Wynn Lisa Blair , Shrivastava Vineet L. , Haydon Michael L. , Wing Deborah A.
Published: January 2014

Objectives

The purpose of this study was to compare the outcomes of triplet pregnancies in women with asymptomatic cervical shortening with and without a cervical cerclage.

Methods

A retrospective review of all triplet pregnancies with biweekly serial cervical length surveillance was performed. Cervical shortening was defined as a cervical length of 2.5 cm or less before 24 weeks' gestation. Patients with cervical shortening managed with cerclage were compared to those managed expectantly. The primary outcome was the gestational age at delivery, with secondary outcomes including birth weight, neonatal intensive care unit length of stay, and composite neonatal outcome. Statistical significance was defined as P < .05.

Results

Sixteen patients underwent cerclage placement versus 8 managed expectantly (control group). The median gestational ages at delivery were similar between the groups (cerclage, 31.3 weeks; interquartile range [IQR], 29.3–32.3 weeks; control, 29.8 weeks; IQR, 27.5–32.4 weeks; P = .71). The median birth weights were also similar between the groups (cerclage, 1283 g; IQR, 800–1626 g; control, 1109 g; IQR, 776–1500 g; P = .54). There was no significant difference in composite neonatal outcomes between the cerclage and control groups (P = .67).

Conclusions

In this limited case‐control study, we found no benefit in terms of pregnancy prolongation or neonatal outcomes with cerclage placement for triplet gestations complicated by an asymptomatic short cervix.
Making Chorionic Villus Sampling Painless for Both the Patient and the Physician
Authors: Gimovsky Alexis , Khodak-Gelman Slava , Larsen John
Published: January 2014

Currently, in common practice, no pain control is provided to the patient undergoing transvaginal chorionic villus sampling (CVS). Chorionic villus sampling is an invasive procedure involving an 18‐gauge needle stick through the abdomen or passage of a suction catheter through the cervix. Furthermore, CVS is a mechanically difficult procedure for the clinician and requires considerable skill and training. There have been prior studies establishing the efficacy of using a topical anesthetic in similar gynecologic procedures. We share our method of performing CVS, which aids in pain relief for the patient and concurrently aids the practitioner in executing this precise procedure.
Nonrandom X Chromosome Inactivation Detection
Authors: Jones Julie R.
Published: January 2014

X chromosome inactivation patterns may be clinically useful in assessing tumor clonality, determining carrier status for certain X‐linked disorders and evaluating the pathogenicity of a genetic variant identified in an X‐linked gene. The protocols in this unit utilize the highly polymorphic trinucleotide repeat within the first exon of the human androgen receptor gene (AR) and the methylation‐sensitive restriction enzyme HpaII to distinguish between the maternal and paternal alleles and simultaneously determine their methylation status. The data obtained from these protocols can be used to calculate the ratio of inactivation between the two alleles that ultimately reflects whether a female has a random or nonrandom pattern of X chromosome inactivation. Curr. Protoc. Hum. Genet. 80:9.7.1‐9.7.7. © 2014 by John Wiley & Sons, Inc.
Anisotropy beneath a highly extended continental rift
Authors: Eilon Zachary , Abers Geoffrey A. , Jin Ge , Gaherty James B.
Published: January 2014

We have employed shear wave splitting techniques to image anisotropy beneath the D'Entrecasteaux Islands, in southeastern Papua New Guinea. Our results provide a detailed picture of the extending continent that lies immediately ahead of a propagating mid‐ocean ridge tip; we image the transition from continental to oceanic extension. A dense shear wave splitting data set from a 2010 to 2011 passive‐source seismic deployment is analyzed using single and multichannel methods. Splitting delay times of 1–1.5 s are observed and fast axes of anisotropy trending N‐S, parallel to rifting direction, predominate the results. This trend is linked to lattice‐preferred orientation of olivine, primarily in the shallow convecting mantle, driven by up to 200 km of N‐S continental extension ahead of the westward‐propagating Woodlark Rift. This pattern differs from several other continental rifts that evince rift‐strike‐parallel fast axes and is evident despite the complex recent tectonic history. We contend that across most of this rift, the unusually high rate and magnitude of extension has been sufficient to produce a regime change to a mid‐ocean‐ridge‐like mantle fabric. Stations in the south of our array show more complex splitting that might be related to melt or to complex inherited structure at the edge of the extended region.
The response to MJO‐like forcing in a nonlinear shallow‐water model
Authors: Bao Ming , Hartmann Dennis L.
Published: January 2014

This study examines the response to Madden‐Julian Oscillation (MJO)‐like heat forcing in a nonlinear shallow‐water model, including monopolar heating source traveling eastward with an around the world period of 48 days and dipolar heating with zonal wave period of 48 days, with zonal wave number 2 confined in longitude to the MJO active regions. A jet localized in the Pacific is compared to a zonally uniform boreal basic flow. The results show that the Rossby wave response downstream exhibits intensified quasi‐stationary anomalies in the Pacific jet exit region when the MJO‐like heat forcing passes the Maritime Continent, in accord with the observational analysis by Adames and Wallace (2014). The dynamical mechanism suggested in this study can be used to interpret the intraseasonal MJO‐Pacific North American pattern coherence and other extratropical intraseasonal events.
Pressure‐induced enhancement of proton conduction in brucite
Authors: Guo Xinzhuan , Yoshino Takashi
Published: January 2014

The electrical conductivity of single‐crystal brucite was measured as a function of pressure and temperature (P‐T) using impedance spectroscopy (IS). IS measurements demonstrated that electrical conductivity perpendicular to the c axis is nearly half order of magnitude higher than that parallel to the c axis under the same P‐T conditions. Electrical conductivity increased by 2 orders of magnitude during compression from 3.7 to 11 GPa, irrespective of crystallographic direction. However, the conductivity increase with pressure became less significant upon further compression from 11 to 13 GPa. The pressure effect is closely related to the interactions between neighboring hydroxyls. The ratio of free protons to total hydrogen increases from 2% to 33% when pressure increases from 3.7 to 13 GPa at 950 K. This indicates that most of the protons are bound within the crystal structure at low pressures, whereas more protons become free and mobile at higher pressures.
Mobilization of optically invisible dissolved organic matter in response to rainstorm events in a tropical forest headwater river
Authors: Pereira Ryan , Isabella Bovolo C. , Spencer Robert G. M. , Hernes Peter J. , Tipping Edward , Vieth‐Hillebrand Andrea , Pedentchouk Nikolai , Chappell Nick A. , Parkin Geoff , Wagner Thomas
Published: January 2014

This study emphasizes the importance of rainstorm events in mobilizing carbon at the soil‐stream interface from tropical rainforests. Half‐hourly geochemical/isotopic records over a 13.5 h period from a 20 km2 tropical rainforest headwater in Guyana show an order of magnitude increase in dissolved organic carbon (DOC) concentration in less than 30 mins (10.6–114 mg/L). The composition of DOC varies significantly and includes optically invisible dissolved organic matter (iDOM) that accounts for a large proportion (4–89%) of the total DOC, quantified using size exclusion chromatography (SEC). SEC suggests that iDOM is comprised of low molecular weight organic moieties, which are likely sourced from fresh leaf litter and/or topsoil, as shown in soils from the surrounding environment. Although poorly constrained at present, the presence of iDOM further downstream during the wet season suggests that this organic matter fraction may represent an unquantified source of riverine CO2 outgassing in tropical headwaters, requiring further consideration.
Passive margin subduction and the dynamics of collisional orogenesis
Authors: Schoettle‐Greene P. , Pysklywec R. N.
Published: January 2014

Continental passive margins are characterized by a wide variety of geometries and widths. Whether these variations have an influence on subsequent dynamics of orogenesis is unresolved. To investigate, a series of upper mantle numerical experiments were performed with systematically varied continental margin widths and geometries. Results show that the vertical geometry of subducting continental margin crust controls both crustal and mantle lithosphere deformation. On both scales, end‐members can be identified. Namely, break‐off versus delamination of continental mantle lithosphere and double vergence versus single vergence of crustal thrust fronts form as a direct result of passive margin geometry. We find that the subduction of upper crust to depths >100 km promotes lithospheric delamination and is facilitated by an extended passive margin. Modeled orogens show decreasing upper plate deformation with increasing margin width. These results suggest that along‐strike deformational variation within orogens may develop due to precollision passive margin geometry.
Tracking high‐frequency seismic source evolution: 2004 Mw 8.1 Macquarie event
Authors: Kennett B. L. N. , Gorbatov A. , Spiliopoulos S.
Published: January 2014

The 2004 Mw 8.1 event on 23 December 2004 near the Macquarie Ridge is a very large intraplate event that has been overshadowed by the Mw 9.3 Sumatra‐Andaman event only 3 days later. We are able to track the progress of source evolution by estimating the progression of the points of energy emission, exploiting the good azimuthal distribution of available stations. The results indicate that this event ruptured on two nearby fault systems reactivating fossil fracture zones, with the second subevent to the west triggered by the first. The total duration of high‐frequency radiation is quite short, about 60 s, for such a large event. Much of the high‐frequency radiation occurs on a fault subparallel to that inferred from long‐period studies. This composite fault behavior with displaced triggered failure appears to be a characteristic of large intraplate events beneath the oceans.
Advanced spectral analysis of ionospheric waves observed with sparse arrays
Authors: Helmboldt J. F. , Intema H. T.
Published: January 2014

This paper presents a case study from a single, 6h observing period to illustrate the application of techniques developed for interferometric radio telescopes to the spectral analysis of observations of ionospheric fluctuations with sparse arrays. We have adapted the deconvolution methods used for making high dynamic range images of cosmic sources with radio arrays to making comparably high dynamic range maps of spectral power of wavelike ionospheric phenomena. In the example presented here, we have used observations of the total electron content (TEC) gradient derived from Very Large Array (VLA) observations of synchrotron emission from two galaxy clusters at 330MHz as well as GPS‐based TEC measurements from a sparse array of 33 receivers located within New Mexico near the VLA. We show that these techniques provide a significant improvement in signal‐to‐noise ratio (S/N) of detected wavelike structures by correcting for both measurement inaccuracies and wavefront distortions. This is especially true for the GPS data when combining all available satellite/receiver pairs, which probe a larger physical area and likely have a wider variety of measurement errors than in the single‐satellite case. In this instance, we found that the peak S/N of the detected waves was improved by more than an order of magnitude. The data products generated by the deconvolution procedure also allow for a reconstruction of the fluctuations as a two‐dimensional waveform/phase screen that can be used to correct for their effects.
Energy coupling during the August 2011 magnetic storm
Authors: Huang C. Y. , Su Y.‐J. , Sutton E. K. , Weimer D. R. , Davidson R. L.
Published: January 2014

We present results from an analysis of high‐latitude ionosphere‐thermosphere (IT) coupling to the solar wind during a moderate magnetic storm which occurred on 5–6 August 2011. During the storm, a multipoint set of observations of the ionosphere and thermosphere was available. We make use of ionospheric measurements of electromagnetic and particle energy made by the Defense Meteorological Satellite Program and neutral densities measured by the Gravity Recovery and Climate Experiment satellite to infer (1) the energy budget and (2) timing of the energy transfer process during the storm. We conclude that the primary location for energy input to the IT system may be the extremely high latitude region. We suggest that the total energy available to the IT system is not completely captured either by observation or empirical models.
Chorus wave scattering responsible for the Earth's dayside diffuse auroral precipitation: A detailed case study
Authors: Ni Binbin , Bortnik Jacob , Nishimura Yukitoshi , Thorne Richard M. , Li Wen , Angelopoulos Vassilis , Ebihara Yusuke , Weatherwax Allan T.
Published: January 2014

The diffuse aurora is an almost permanent feature in the Earth's upper polar atmosphere, providing the major source of ionizing energy input into the high‐latitude region. Previous theoretical and observational studies have demonstrated that whistler mode chorus scattering primarily accounts for intense nightside diffuse auroral precipitation within ~ 8 RE, but what causes the dayside diffuse aurora remains poorly understood. Using conjugate satellite wave and particle observations on 13 August 2009 from the Time History of Events and Macroscale Interactions during Substorms spacecraft and ground‐based all‐sky imager measurements at the South Pole on the dayside, we perform a quantitative analysis of wave‐driven diffusion and electron precipitation. Our results demonstrate that the dayside chorus scattering was the dominant contributor to the observed dayside diffuse auroral precipitation and that the chorus wave intensity primarily controlled its brightness, indicating that dayside chorus can be the major driver of the Earth's dayside diffuse aurora. While further investigations are required to bring closure to the origin of the dayside diffuse aurora under differing solar wind conditions and geomagnetic situations, our finding is an important complement to recent work on the formation mechanism of the diffuse aurora and provides improved understanding of the roles of resonant wave‐particle interactions in diffuse auroral precipitation pattern on a global scale.
On the use of geomagnetic indices and ULF waves for earthquake precursor signatures
Authors: Currie J. L. , Waters C. L.
Published: January 2014

Ultralow frequency (ULF: 0.001–5 Hz) magnetic records have recently been used in the search for short‐term earthquake prediction methods. The separation of local and global effects in the magnetic records is the greatest challenge in this research area. Geomagnetic indices are often used to predict global ULF magnetic behavior where it is assumed that increases in a geomagnetic index correspond with an increase in ULF power. This paper examines the relationships between geomagnetic indices and ULF power, spectral polarization ratio, and the relationship between the spectral polarization ratio and solar wind parameters. The power in the ULF, Pc3‐5 bands (10–600 s), shows a linear correlation coefficient of 0.2 with the Kp magnetic activity index. The correlation varies with magnetic local time (MLT) and latitude. The correlation coefficient is inversely related to the integrated power in the ULF Pc3 band (10–45 s) over MLT and magnetic latitude. The ratio of spectral powers Z(ω)/G(ω) is discussed and shown to be a promising parameter in the search for earthquake precursor signals in ULF records.
Testing a two‐loop pattern of the substorm current wedge (SCW2L)
Authors: Sergeev V. A. , Nikolaev A. V. , Tsyganenko N. A. , Angelopoulos V. , Runov A. V. , Singer H. J. , Yang J.
Published: January 2014

Recent quantitative testing of the classical (region 1 sense) substorm current wedge (SCI) model revealed systematic discrepancies between the observed and predicted amplitudes, which suggested us to include additional region 2 sense currents (R2 loop) earthward of the dipolarized region (SCW2L model). Here we discuss alternative circuit geometries of the 3‐D substorm current system and interpret observations of the magnetic field dipolarizations made between 6.6RE and 11RE, to quantitatively investigate the SCW2L model parameters. During two cases of a dipole‐like magnetotail configuration, the dipolarization/injection front fortuitously stopped at r ~ 9RE for the entire duration of ~ 30 min long SCW‐related dipolarization within a unique, radially distributed multispacecraft constellation, which allowed us to determine the locations and total currents of both SCW2L loops. In addition, we analyzed the dipolarization amplitudes in events, simultaneously observed at 6.6RE, 11RE and at colatitudes under a wide range of magnetograph conditions. We infer that the ratio I2/I1 varies in the range 0.2 to 0.6 (median value 0.4) and that the equatorial part of the R2 current loop stays at r>6.6RE in the case of a dipole‐like field geometry (BZ0>75 nT at 6.6RE prior to the onset), but it is located at r<6.6RE in the case of a stretched magnetic field configuration (with BZ0<60 nT). Since the ground midlatitude perturbations are sensitive to the combined effect of the R1 and R2 sense current loops with the net current roughly equal to I1−I2, the ratio I2/I1 becomes an important issue when attempting to monitor the current disruption intensity from ground observations.
Northern hemispheric winter warming pattern after tropical volcanic eruptions: Sensitivity to the ozone climatology
Authors: Muthers S. , Anet J. G. , Raible C. C. , Brönnimann S. , Rozanov E. , Arfeuille F. , Peter T. , Shapiro A. I. , Beer J. , Steinhilber F. , Brugnara Y. , Schmutz W.
Published: January 2014

An important key for the understanding of the dynamic response to large tropical volcanic eruptions is the warming of the tropical lower stratosphere and the concomitant intensification of the polar vortices. Although this mechanism is reproduced by most general circulation models today, most models still fail in producing an appropriate winter warming pattern in the Northern Hemisphere. In this study ensemble sensitivity experiments were carried out with a coupled atmosphere‐ocean model to assess the influence of different ozone climatologies on the atmospheric dynamics and in particular on the northern hemispheric winter warming. The ensemble experiments were perturbed by a single Tambora‐like eruption. Larger meridional gradients in the lower stratospheric ozone favor the coupling of zonal wind anomalies between the stratosphere and the troposphere after the eruption. The associated sea level pressure, temperature, and precipitation patterns are more pronounced and the northern hemispheric winter warming is highly significant. Conversely, weaker meridional ozone gradients lead to a weaker response of the winter warming and the associated patterns. The differences in the number of stratosphere‐troposphere coupling events between the ensembles experiments indicate a nonlinear response behavior of the dynamics with respect to the ozone and the volcanic forcing.
The effects of temperature and nitrogen and sulfur additions on carbon accumulation in a nutrient‐poor boreal mire: Decadal effects assessed using 210Pb peat chronologies
Authors: Olid Carolina , Nilsson Mats B. , Eriksson Tobias , Klaminder Jonatan
Published: January 2014

Boreal peatlands are a major long‐term reservoir of atmospheric carbon (C) and play an important role in the global C cycle. It is unclear how C accumulation in peatlands responds to changing temperatures and nutrients (specifically, nitrogen and sulfur). In this study, we assessed how the C input rate and C accumulation rate in decadal old peat layers respond to increased air temperatures (+3.6°C) during the growing season and the annual additions of nitrogen (N) and sulfur (S) (30 and 20 kg ha−1 yr−1, respectively) over 12 years of field treatments in a boreal mire. An empirical mass balance model was applied to 210Pb‐dated peat cores to evaluate changes in C inputs, C mass loss, and net C accumulation rates in response to the treatments. We found that (i) none of the treatments generated a significant effect on peat mass loss decay rates, (ii) C input rates were positively affected by N additions and negatively affected by S additions, (iii) the C accumulation rate in the uppermost (10 to 12 cm) peat was increased by N additions and decreased by S additions, and (iv) only air temperature significantly affected the main effects induced by N and S additions. Based on our findings, we argue that C accumulation rates in surface peat layers of nutrient‐poor boreal mires can increase despite the predicted rise in air temperatures as long as N loads increase and acid atmospheric S remains low.
Beyond leaf color: Comparing camera‐based phenological metrics with leaf biochemical, biophysical, and spectral properties throughout the growing season of a temperate deciduous forest
Authors: Yang Xi , Tang Jianwu , Mustard John F.
Published: January 2014

Plant phenology, a sensitive indicator of climate change, influences vegetation‐atmosphere interactions by changing the carbon and water cycles from local to global scales. Camera‐based phenological observations of the color changes of the vegetation canopy throughout the growing season have become popular in recent years. However, the linkages between camera phenological metrics and leaf biochemical, biophysical, and spectral properties are elusive. We measured key leaf properties including chlorophyll concentration and leaf reflectance on a weekly basis from June to November 2011 in a white oak forest on the island of Martha's Vineyard, Massachusetts, USA. Concurrently, we used a digital camera to automatically acquire daily pictures of the tree canopies. We found that there was a mismatch between the camera‐based phenological metric for the canopy greenness (green chromatic coordinate, gcc) and the total chlorophyll and carotenoids concentration and leaf mass per area during late spring/early summer. The seasonal peak of gcc is approximately 20 days earlier than the peak of the total chlorophyll concentration. During the fall, both canopy and leaf redness were significantly correlated with the vegetation index for anthocyanin concentration, opening a new window to quantify vegetation senescence remotely. Satellite‐ and camera‐based vegetation indices agreed well, suggesting that camera‐based observations can be used as the ground validation for satellites. Using the high‐temporal resolution dataset of leaf biochemical, biophysical, and spectral properties, our results show the strengths and potential uncertainties to use canopy color as the proxy of ecosystem functioning.
Spatial patterns of vegetation, soils, and microtopography from terrestrial laser scanning on two semiarid hillslopes of contrasting lithology
Authors: Harman Ciaran J. , Lohse Kathleen A. , Troch Peter A. , Sivapalan Murugesu
Published: January 2014

Shrublands in semiarid regions are heterogeneous landscapes consisting of infertile bare areas separated by nutrient rich vegetated areas known as resource islands. Spatial patterns in these landscapes are structured by feedbacks driven by the transport of water and nutrient resources from the intershrub space to areas below shrubs, and the retention of these resources to locally drive productivity and tight biogeochemical cycles. Most understanding of plant‐soil feedbacks is based predominantly on studies of low topographic gradient landscapes, and it is unclear whether the patterns of association between soils and vegetation, and the autogenic processes that create them, also occur on more steeply sloping terrain. Here we analyze the spatial patterns of soils, vegetation, and microtopography on hillslopes of contrasting lithology (one granite at 16°, one schist at 27°) in the Sonoran desert foothills of the Catalina Mountains. We also describe a method of extracting vegetation density from terrestrial laser scanning point cloud data at 5 cm × 5 cm scales and find that it correlates well with soil organic carbon measurements. Vegetation was associated with microtopographic mounds (relative to the mean slope) extending 0.3 m downslope and 1.8 m (schist) and 0.9 m (granite) upslope on the study hillslopes. Soils below the shrub canopies exhibited 2–3 times more soil organic matter and 2–4 times higher hydraulic conductivity than the interspaces. Soils enriched with organic matter were found to extend at least two canopy radii downslope of woody shrubs, but not upslope. These plumes were clearest in the lower gradient granite site where vegetation mounds created distinct patterns of microtopographic convergence and divergence. At the steeper schist site, microtopography appeared to have a weaker control on topographic flow accumulation. Collectively, our findings suggest that the spatial structure of association between soils and microtopography and vegetation on these slopes exhibit many of the features observed in lower gradient areas. However, microtopography and soils are more asymmetric along the downslope axis of the hillslopes than lower gradient areas and vary with lithology. Alluvial and colluvial processes are likely more important in shaping vegetation and soil dynamics on hillslopes, and these factors need further consideration in scaling results to the landscape level.
Western U.S. Water Supply Forecasting: A Tradition Evolves
Authors: Pagano Thomas , Wood Andrew , Werner Kevin , Tama‐Sweet Rashawn
Published: January 2014

Since 2011, the U.S. Department of Agriculture (USDA) Natural Resources Conservation Service (NRCS) and three major river forecasting centers of the National Oceanic and Atmospheric Administration's (NOAA) National Weather Service (NWS) have discontinued a long‐standing practice of publishing consensus water supply forecasts in western U.S. river basins.
Modern Arctic temperatures unprecedented in past 44,000 years
Authors: Schultz Colin
Published: January 2014

When the temperature rises on Baffin Island, in the Canadian high Arctic, ancient Polytrichum mosses are exposed from beneath melting glacier ice. Within a few years of exposure the mosses are quickly eroded away by snow and wind, but trapped beneath the ice, they can remain, frozen, for thousands of years.
Simulations of scalar dispersion in fluidized solid–liquid suspensions
Authors: Derksen J. J.
Published: January 2014

Direct, particle‐resolved simulations of solid–liquid fluidization with the aim of quantifying dispersion have been performed. In addition to simulating the multiphase flow dynamics (that is dealt with by a lattice‐Boltzmann method coupled to an event‐driven hard‐sphere algorithm), a transport equation of a passive scalar in the liquid phase has been solved by means of a finite‐volume approach. The spreading of the scalar—as a consequence of the motion of the fluidized, monosized spherical particles that agitate the liquid—is quantified through dispersion coefficients. Particle self‐diffusivities have also been determined. Solids volume fractions were in the range 0.2–0.5, whereas single‐sphere settling Reynolds numbers varied between approximately 3 and 20. The dispersion processes are highly anisotropic with lateral spreading much slower (by one order of magnitude) than vertical spreading. Scalar dispersion coefficients are of the same order of magnitude as particle self‐diffusivities. © 2014 American Institute of Chemical EngineersAIChE J, 60: 1880–1890, 2014
Predicting Alzheimer disease with β‐amyloid imaging: Results from the Australian imaging, biomarkers, and lifestyle study of ageing
Authors: Rowe Christopher C. , Bourgeat Pierrick , Ellis Kathryn A. , Brown Belinda , Lim Yen Ying , Mulligan Rachel , Jones Gareth , Maruff Paul , Woodward Michael , Price Roger , Robins Peter , Tochon‐Danguy Henri , O'Keefe Graeme , Pike Kerryn E. , Yates Paul , Szoeke Cassandra , Salvado Olivier , Macaulay S. Lance , O'Meara Timothy , Head Richard , Cobiac Lynne , Savage Greg , Martins Ralph , Masters Colin L. , Ames David , Villemagne Victor L.
Published: January 2014

Objective

Biomarkers for Alzheimer disease (AD) can detect the disease pathology in asymptomatic subjects and individuals with mild cognitive impairment (MCI), but their cognitive prognosis remains uncertain. We aimed to determine the prognostic value of β‐amyloid imaging, alone and in combination with memory performance, hippocampal atrophy, and apolipoprotein E ε4 status in nondemented, older individuals.

Methods

A total of 183 healthy individuals (age = 72.0 ± 7.26 years) and 87 participants with MCI (age = 73.7 ± 8.27) in the Australian Imaging, Biomarkers, and Lifestyle study of ageing were studied. Clinical reclassification was performed after 3 years, blind to biomarker findings. β‐Amyloid imaging was considered positive if the 11C‐Pittsburgh compound B cortical to reference ratio was ≥1.5.

Results

Thirteen percent of healthy persons progressed (15 to MCI, 8 to dementia), and 59% of the MCI cohort progressed to probable AD. Multivariate analysis showed β‐amyloid imaging as the single variable most strongly associated with progression. Of combinations, subtle memory impairment (Z score = −0.5 to −1.5) with a positive amyloid scan was most strongly associated with progression in healthy individuals (odds ratio [OR] = 16, 95% confidence interval [CI] = 3.7–68; positive predictive value [PPV] = 50%, 95% CI = 19–81; negative predictive value [NPV] = 94%, 95% CI = 88–98). Almost all amnestic MCI subjects (Z score ≤ −1.5) with a positive amyloid scan developed AD (OR = ∞; PPV = 86%, 95% CI = 72–95; NPV = 100%, 95% CI = 80–100). Hippocampal atrophy and ε4 status did not add further predictive value.

Interpretation

Subtle memory impairment with a positive β‐amyloid scan identifies healthy individuals at high risk for MCI or AD. Clearly amnestic patients with a positive amyloid scan have prodromal AD and a poor prognosis for dementia within 3 years. Ann Neurol 2013;74:905–913
Multivalente synthetische Glycopeptid‐Lipopeptid‐Antitumorvakzine: Auswirkung des Cluster‐Effekts auf das Abtöten von Tumorzellen
Authors: Cai Hui , Sun Zhan‐Yi , Chen Mei‐Sha , Zhao Yu‐Fen , Kunz Horst , Li Yan‐Mei
Published: January 2014

Multivalente synthetische Vakzine wurden durch Festphasensynthese von tumorassoziierten MUC1‐Glycopeptidantigenen und deren Kupplung an ein Pam3Cys‐Lipopeptid durch Klick‐Reaktion gewonnen. Diese Vakzine lösen in Mäusen Immunreaktionen aus, ohne dass externe Adjuvantien angewendet werden. Die vier MUC1‐Sialyl‐TN‐Antigene enthaltende Vakzine zeigte einen signifikanten Cluster‐Effekt. Sie induzierte in Mäusen vorwiegend IgG2a‐Antikörper, die an MCF‐7‐Brusttumorzellen binden und diese Tumorzellen durch Aktivierung des Complement‐abhängigen Cytotoxizitätskomplexes (CDC) abtöten.
Polymerization of Ethylene by Silica‐Supported Dinuclear CrIII Sites through an Initiation Step Involving CH Bond Activation
Authors: Conley Matthew P. , Delley Murielle F. , Siddiqi Georges , Lapadula Giuseppe , Norsic Sébastien , Monteil Vincent , Safonova Olga V. , Copéret Christophe
Published: January 2014

The insertion of an olefin into a preformed metal–carbon bond is a common mechanism for transition‐metal‐catalyzed olefin polymerization. However, in one important industrial catalyst, the Phillips catalyst, a metal–carbon bond is not present in the precatalyst. The Phillips catalyst, CrO3 dispersed on silica, polymerizes ethylene without an activator. Despite 60 years of intensive research, the active sites and the way the first CrC bond is formed remain unknown. We synthesized well‐defined dinuclear CrII and CrIII sites on silica. Whereas the CrII material was a poor polymerization catalyst, the CrIII material was active. Poisoning studies showed that about 65 % of the CrIII sites were active, a far higher proportion than typically observed for the Phillips catalyst. Examination of the spent catalyst and isotope labeling experiments showed the formation of a Si–(μ‐OH)–CrIII species, consistent with an initiation mechanism involving the heterolytic activation of ethylene at CrIIIO bonds.
Block copolymers for protein ordering
Authors: Malmström Jenny , Travas‐Sejdic Jadranka
Published: January 2014

Large scale production of sub‐micrometer features aids vital understanding of the interactions present at that scale in the biological world as well as the interactions with artificial surfaces. Considerable research efforts have been put into the study and control of block copolymer self‐assembly, both in bulk phase and as thin films. Well‐ordered block copolymer films can be used for pattern transfer through etching or evaporation and have also been explored as templates for directed nanoparticle assembly and as hosts for proteins. This review is focused on the emerging area of using block copolymer films for the creation of ordered arrays of protein or peptides. The work done in the field is reviewed and focus is being put on how the systems have been characterized as this is an inherent difficulty of such systems. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40360.
Microstructure, rheological behavior, and properties of poly(lactic acid)/poly(butylene succinate)/organoclay nanocomposites
Authors: Risse Sophie , Tighzert Lan , Berzin Françoise , Vergnes Bruno
Published: January 2014

Nanocomposites made of poly(lactic acid), poly(butylene succinate), and organically modified montmorillonite were prepared by melt blending in a twin screw extruder. The influence of the organoclay content on nanocomposite properties was investigated. The nanocomposite structure has been characterized by various techniques at different scales. X‐ray diffraction showed an intercalated structure whereas rheological investigations in small amplitude oscillatory shear indicated a partial exfoliation. It was also shown that organoclay was evenly dispersed in the matrix even though some large aggregates were also observed. The mechanical properties of nanocomposites were measured in uniaxial tensile test. Oxygen and water vapor permeability was also characterized. It was shown that dispersed organoclay and aggregates have a direct impact on mechanical properties and permeability. An increase of Young's modulus by 41% and a decrease of permeability by 40% could be obtained with 7 wt % organoclay. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40364.
Synthesis and Pharmacological Evaluation of Novel 1′‐[2‐(Difluoromethoxy)benzyl]‐2′H,5′H‐spiro[8‐azabicyclo[3.2.1]octane‐3,4′‐imidazolidine]‐2′,5′‐diones and Their Derivatives
Authors: Madaiah Malavalli , Prashanth Maralekere K. , Revanasiddappa Hosakere D. , Veeresh Bantal
Published: January 2014

A series of novel 1′‐[2‐(difluoromethoxy)benzyl]‐2′H,5′H‐spiro[8‐azabicyclo[3.2.1]octane‐3,4′‐imidazolidine]‐2′,5′‐dione substituted hydantoins (5–32) were synthesized using an appropriate synthetic route and characterized by elemental analysis and spectral data. The novel molecules were screened for anticonvulsant activity in mice by maximal electroshock (MES) and subcutaneous pentylenetetrazol (ScPTZ)‐induced seizure tests. The neurotoxicity was assessed using the rotarod method. Compounds 9, 10, 18, 30, and 31 exhibited anticonvulsant potency against MES seizure and in the ScPTZ model, with lesser neurotoxicity. Some title compounds showed lesser central nervous system depression compared to phenytoin.
Gas Sorption Studies on a Microporous Coordination Polymer Assembled from 2D Grid Layers by Strong π–π Interactions
Authors: Lv Xiaoxia , Li Liangjun , Sun Xiaoming , Zhang Hongyu , Cai Jinjun , Wang Chao , Tang Sifu , Zhao Xuebo
Published: January 2014

The microporous coordination polymer [Co(H2L)(bipy)0.5]⋅2 H2O (1, bipy=4,4′‐bipyridine) was synthesized on the basis of the V‐shaped flexible diphosphonate ligand (2,4,6‐trimethyl‐1,3‐phenylene)bis(methylene)diphosphonic acid (H4L) and the auxiliary bipy ligand under hydrothermal conditions. The structure of this compound was characterized by single‐crystal X‐ray diffraction. By joining the diphosphonate ligands and bipy through tetrahedral [CoO3N] clusters, a 2D square grid layered network was formed. Further stacking of these layers on the basis of π–π interactions resulted in a pseudo‐3D microporous network with 1D channels running through the a axis. Gas sorption studies for CO2, H2, CH4, N2, and O2 on this coordination polymer were performed, and the results revealed interesting dynamic and hysteresis sorption behavior toward H2 at low temperature.
Teaching the structure of immunoglobulins by molecular visualization and SDS‐PAGE analysis
Authors: Rižner Tea Lanišnik
Published: January 2014

This laboratory class combines molecular visualization and laboratory experimentation to teach the structure of the immunoglobulins (Ig). In the first part of the class, the three‐dimensional structures of the human IgG and IgM molecules available through the RCSB PDB database are visualized using freely available software. In the second part, IgG and IgM are studied using electrophoretic methods. Through SDS‐PAGE analysis under reducing conditions, the students determine the number and molecular masses of the polypeptide chains, while through SDS‐PAGE under nonreducing conditions, the students assess the oligomerization of these Ig molecules. The aims of this class are to expand upon the knowledge and understanding of the Ig structure that the students have gained from classroom lectures. The combination of this molecular visualization of the Ig molecules and the SDS‐PAGE experimentation ensures variety in the teaching techniques, while the implication of the Ig molecules in human disease promotes interest for biomedical students. © 2014 by The International Union of Biochemistry and Molecular Biology, 42(2):152–159, 2014.
An educational software tool to teach hyper‐heuristics to engineering students based on the bubble breaker puzzle
Authors: Salcedo‐Sanz S. , Jiménez‐Fernández S. , Matías‐Román J. M. , Portilla‐Figueras J. A.
Published: January 2014

This paper presents an educational software tool to teach Artificial Intelligence (AI) techniques, specifically Hyper‐heuristics, to Engineering students. This tool is based on the “Bubble Breaker” puzzle, an addictive game consisting in an M × M matrix of colored bubbles. These balls, when forming sets of two or more same colored balls, can be popped and cleared out. Thus, this puzzle can be solved by setting many different low‐level heuristics and applying a global search procedure (i.e., evolutionary algorithm) that conforms a robust hyper‐heuristic technique. The hyper‐heuristic decides what low‐level heuristics are the best, and the sequential way in which they have to be applied to gain the highest score. This approach has proven an interesting method to teach AI techniques, since simple heuristics, evolutionary algorithms, and its combination are studied in an increasing manner. © 2014 Wiley Periodicals, Inc. Comput Appl Eng Educ 23:277–285, 2015; View this article online at wileyonlinelibrary.com/journal/cae; DOI 10.1002/cae.21597
Control of Plant Defense Mechanisms and Fire Blight Pathogenesis through the Regulation of 6‐Thioguanine Biosynthesis in Erwinia amylovora
Authors: Coyne Sébastien , Litomska Agnieszka , Chizzali Cornelia , Khalil Mohammed N. A. , Richter Klaus , Beerhues Ludger , Hertweck Christian
Published: January 2014

Fire blight is a devastating disease of Rosaceae plants, such as apple and pear trees. It is characterized by necrosis of plant tissue, caused by the phytopathogenic bacterium Erwinia amylovora. The plant pathogen produces the well‐known antimetabolite 6‐thioguanine (6TG), which plays a key role in fire blight pathogenesis. Here we report that YcfR, a member of the LTTR family, is a major regulator of 6TG biosynthesis in E. amylovora. Inactivation of the regulator gene (ycfR) led to dramatically decreased 6TG production. Infection assays with apple plants (Malus domestica cultivar Holsteiner Cox) and cell cultures of Sorbus aucuparia (mountain ash, rowan) revealed abortive fire blight pathogenesis and reduced plant response (biphenyl and dibenzofuran phytoalexin production). In the presence of the ΔycfR mutant, apple trees were capable of activating the abscission machinery to remove infected tissue. In addition to unveiling the regulation of 6TG biosynthesis in a major plant pathogen, we demonstrate for the first time that this antimetabolite plays a pivotal role in dysregulating the plant response to infection.
Nickel Boosts Ring‐Opening Activity of Iridium
Authors: Ziaei‐Azad Hessam , Semagina Natalia
Published: January 2014

A variety of bimetallic Ni–Ir catalysts were synthesised by preforming nanoparticles in the presence of polyvinylpyrrolidone, followed by deposition on γ‐alumina and high‐temperature polymer removal. The Ni–Ir (1:1 molar ratio) nanoparticles prepared by the hydrogen‐sacrificial technique (Ir reduction on the preformed Ni nanoparticles with surface Ni hydride) allowed increasing indane ring opening activity per total amount of Ir as compared to monometallic Ir. The simultaneous reduction of Ni and Ir precursors was not as efficient. The catalysts were characterised with UV/Vis spectroscopy, TEM, temperature‐programmed reduction, CO2 temperature‐programmed desorption, CO diffuse reflectance Fourier transform spectroscopy, X‐ray photoelectron spectroscopy and CHN analysis. The study only explored the catalyst’s metal function and allows saving rare and expensive iridium without loss of its outstanding performance as a ring‐opening catalyst.
Cereus‐Shaped Mesoporous Rutile TiO2 Formed in Ionic Liquid: Synthesis and Li‐Storage Properties
Authors: Suo Liumin , Sallard Sébastien , Hu Yong‐Sheng , Smarsly Bernd M. , Chen Liquan
Published: January 2014

Mesoporous rutile TiO2 with a cereus‐shaped structure was synthesized through a low‐temperature sol‐gel synthesis approach in a bromide ionic liquid/water mixture. The electrochemical Li‐storage performance of the annealed material exhibits a high reversible capacity, long cycling stability, and excellent rate capability.