bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental study on ethanol production from hydrothermal pretreated rapeseed straw by simultaneous saccharification and fermentation
Authors: López‐Linares Juan C. , Romero Inmaculada , Cara Cristóbal , Ruiz Encarnación , Castro Eulogio , Moya Manuel
Published: May 2013

BACKGROUND

Rapeseed straw is an agricultural residue increasingly produced in recent years due to a growing interest in biodiesel production. In the present study, rapeseed straw pretreated by liquid hot water was tested as a substrate to optimize ethanol production by simultaneous saccharification and fermentation (SSF). Temperature, time, substrate loading and cellulase charge were selected as operation variables and modified according to a three‐level four‐variable experimental design. Ethanol concentration, ethanol yield and volumetric productivity were monitored and adjusted to a quadratic model using response surface methodology.

RESULTS

Optimal SSF conditions, based on the mathematical model in terms of ethanol yield and concentration, were found to be 40°C, 71 h, 10% substrate loading, and 40 FPU g−1 substrate. The resulting ethanol concentration was 23 g L−1, which corresponds to 69% ethanol yield.

CONCLUSION

Liquid hot water is an effective pretreatment that increased the cellulose concentration of rapeseed straw, making it a good substrate for SSF, with a maximum yield of 0.12 g ethanol g–1 dry straw. The novel combination of hydrothermal pretreatment and SSF configuration results in yields comparable yields with those previously reported, and has additional advantages, e.g. no chemicals use and high solid concentration operation. © 2013 Society of Chemical Industry
Metapodial or Phalanx? An Evolutionary and Developmental Perspective on the Homology of the First Ray's Proximal Segment
Authors: RENO PHILIP L. , HORTON WALTER E. , LOVEJOY C. Owen
Published: May 2013

The first mammalian metapodial (MP1) has periodically been argued to actually be a phalanx, because the first ray has one less element than the four posterior rays, and because the MP1 growth plate is proximal like those of all phalanges, rather than distal as in metapodials 2–5. However, growth plates are formed at both ends in non‐therian tetrapod metapodials, and phylogenetic analysis demonstrates that growth plate loss is a therian synapomorphy that postdates the establishment of the mammalian phalangeal formula. These data, along with results of developmental and morphological studies, suggest that the MP1 is not a phalanx. The singular, proximal growth plates in MPs 2–5 are likely to be an adaptation to dynamic erect quadrupedal gait which was characterized by conversion of the posterior metapodials into rigid struts with the carpus/tarsus. While the adaptive significance of the reversed ossification of MP1 is less clear, we present three functional/developmental hypotheses. J. Exp. Zool. (Mol. Dev. Evol.) 320B:276–285, 2013. © 2013 Wiley Periodicals, Inc.
Fitting method based on correlation maximization: Applications in space physics
Authors: Livadiotis G. , McComas D. J.
Published: May 2013

We develop a new fitting method based on the maximization of the correlation between two curves or sets of discreet observations. We show that this correlation maximization fitting method is mathematically well defined under certain conditions. The key element is the sensitivity of the method—a measure of how localized the correlation maximum is. The most important advantage of the method is that it can be applied to disparate data sets that are expected to be correlated but not fitted to each other. The method is valuable in the analysis of space data sets from (1) physically remote sources that may have complicated and hidden causal linkages or (2) physically distinguished quantities that are reasonably connected. The derived possible relations can be examined by testing the correlation between their observational signals or other measurements. Finally, we examine data of density and temperature in the inner heliosheath, inferred from Interstellar Boundary Explorer observations, and show that the globally distributed flux of energetic neutral atoms represents a source plasma under isobaric thermodynamic processes.
Venus ion outflow estimates at solar minimum: Influence of reference frames and disturbed solar wind conditions
Authors: Nordström T. , Stenberg G. , Nilsson H. , Barabash S. , Zhang T. L.
Published: May 2013

Recent estimates of ion escape rates from Venus, based on ASPERA‐4 data, differ by more than a factor of 4. Whereas the ASPERA‐4 instrument provides state‐of‐the art observations, the limited field of view of the instrument and the strongly limited geographical coverage of the spacecraft orbit means that significant assumptions must be used in the interpretation of the data. We complement previous studies by using a method of average distribution functions to obtain as good statistics as possible while taking the limited field of view into account. We use more than 3 years of data, more than any of the previous studies, and investigate how the choice of a geographical reference frame or a solar wind electric field oriented reference frame affects the results. We find that the choice of reference frame cannot explain the difference between the previously published reports. Our results, based on a larger data set, fall in between the previous studies. Our conclusion is that the difference between previous studies is caused by the large variability of ion outflow at Venus. It matters significantly for the end result which data are selected and which time period is used. The average escape rates were found to be 5.2±1.0×1024 s−1 for heavy ions (m/q ≥16) and 14±2.6×1024 s−1 for protons. We also discuss the spatial distribution of the planetary ion outflow in the solar wind electric field reference frame.
Long‐term ionospheric cooling: Dependency on local time, season, solar activity, and geomagnetic activity
Authors: Zhang Shun‐Rong , Holt John M.
Published: May 2013

Ionospheric ion temperature Ti is an excellent approximation to neutral temperature Tn in the thermosphere, especially for altitudes below 300 km. This analysis of long‒term Ti trends in the F region over different local times is based on a database of incoherent scatter radar (ISR) observations spanning more than three solar cycles during 1968–2006 at Millstone Hill and represents an extended effort to a prior study focusing on noon‒time only. This study provides important information for understanding the difference between the ISR and other results. A gross average of the Ti trend at heights of Ti ∼ Tn (200–350 km) is ∼ −4 K/decade, a cooling trend close to the Tn estimation based on the satellite neutral density data. However, there exists considerable variability in the cooling: it is strong during the day and very weak during the night with a large apparent warming at low altitudes (200–350 km); it is strong at solar minimum for both daytime and nighttime. The strongest cooling for altitudes below 375 km occurs around 90–120 solar flux units of the 10.7 cm solar flux, not at the lowest solar flux. There appears more cooling toward high magnetic activity, but this dependency is very weak. No consistent and substantial seasonal dependency across different heights was found. We speculate that a fraction of the observed cooling trend may be contributed by a gradual shifting away from the sub‒auroral region at Millstone Hill, as part of the secular change in the Earth's magnetic field. In this 39 year long series of data record, two anomalous Ti drops were noticed, and we speculate on their connection to volcano eruptions in 1982 and 1991.
Satellite observations of ozone in the upper mesosphere
Authors: Smith A. K. , Harvey V. L. , Mlynczak M. G. , Funke B. , García‐Comas M. , Hervig M. , Kaufmann M. , Kyrölä E. , López‐Puertas M. , McDade I. , Randall C. E. , Russell J. M. , Sheese P. E. , Shiotani M. , Skinner W. R. , Suzuki M. , Walker K. A.
Published: May 2013

Ozone profiles in the upper mesosphere (70–100 km) retrieved from nine instruments are compared. Ozone from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument is used as the basis of comparison. Other measurements are from the Halogen Occultation Experiment, the High Resolution Doppler Imager, the Michelson Interferometer for Passive Atmospheric Sounding, the Global Ozone Monitoring by Occultation of Stars, the Atmospheric Chemistry Experiment—Fourier Transform Spectrometer, the Solar Occultation For Ice Experiment, the Optical Spectrograph and InfraRed Imaging System, and the Superconducting Submillimeter‐Wave Limb‐Emission Sounder. Comparisons of each data set with SABER using coincident profiles indicate agreement in the basic vertical profile of ozone but also some systematic differences in daytime ozone. Ozone from the SABER 9.6 μm channel is higher than the other measurements over the altitude range 60–80 km by 20–50%. Nighttime comparisons indicate better relative agreement (<10% difference). Taking all the data, not limited to coincidences, shows the global and seasonal distributions of ozone in the upper mesosphere from each instrument. The average maximum in ozone mixing ratio is around 90–92 km during daytime and 95 km at night. There is a maximum in ozone density at night (∼90 km) and during some hours of the day. The latitude structure of ozone has appreciable variations with season, particularly in the tropical upper mesosphere. The basic latitude‐altitude structure of ozone depends on local time, even when the analysis is restricted to day‐only observations.
Intersatellite calibration of NOAA HIRS CO2 channels for climate studies
Authors: Chen Ruiyue , Cao Changyong , Paul Menzel W.
Published: May 2013

The 30 years of observations from the High‐Resolution Infrared Radiation Sounder (HIRS) longwave CO2 channels aboard the NOAA series of satellites are being used to detect climatological changes of cloud. However, the intersatellite radiance discrepancies in the channels need to be removed for the development of a consistent cloud series using HIRS data. By analyzing the intersatellite radiance comparisons at simultaneous‐nadir‐overpass locations for HIRS longwave CO2 channels onboard the NOAA and MetOp series of satellites, this study optimizes the spectral response functions (SRF) for each HIRS to generate a more consistent long‐term set of observations. Intersatellite radiance biases as large as 5% are found for these channels; the spectral differences and spectral uncertainties are shown to be the main causes. To estimate the radiance change for a specific channel due to SRF difference and uncertainty, a linear model is developed to correlate the radiance change for the channel being analyzed with the spectral radiances in the eight selected HIRS channels. The hyperspectral measurements from the Infrared Atmospheric Sounding Interferometer on the MetOp satellite are used to simulate HIRS observations and estimate the parameters of the linear models. The linear models are applied to the NOAA and MetOp HIRS data at simultaneous‐nadir‐overpass locations to estimate the intersatellite radiance differences due to the SRF differences and uncertainties. The intersatellite mean radiance biases are minimized toward zero with residual maximum uncertainty less than 1% after the SRF differences and uncertainties are mitigated. Using the MetOp Infrared Atmospheric Sounding Interferometer as a reference, the optimized SRFs for every NOAA HIRS are found by effectively minimizing the root‐mean‐square values of the intersatellite radiance differences. The optimized shifts of the SRF can be as large as 3 cm−1.
The influence of observation errors on analysis error and forecast skill investigated with an observing system simulation experiment
Authors: Privé N. C. , Errico R. M. , Tai K.‐S.
Published: May 2013

The National Aeronautics and Space Administration Global Modeling and Assimilation Office (NASA/GMAO) observing system simulation experiment (OSSE) framework is used to explore the response of analysis error and forecast skill to observation quality. In an OSSE, synthetic observations may be created that have much smaller error than real observations, and precisely quantified error may be applied to these synthetic observations. Three experiments are performed in which synthetic observations with magnitudes of applied observation error that vary from zero to twice the estimated realistic error are ingested into the Goddard Earth Observing System Model (GEOS‐5) with Gridpoint Statistical Interpolation (GSI) data assimilation for a 1 month period representing July. The analysis increment and observation innovation are strongly impacted by observation error, with much larger variances for increased observation error. The analysis quality is degraded by increased observation error, but the change in root‐mean‐square error of the analysis state is small relative to the total analysis error. Surprisingly, in the 120 h forecast, increased observation error only yields a slight decline in forecast skill in the extratropics and no discernible degradation of forecast skill in the tropics.
An assessment of cirrus heights from MISR oblique stereo using ground‐based radar and lidar at the Tropical Western Pacific ARM sites
Authors: Prasad Abhnil Amtesh , Davies Roger
Published: May 2013

We compare cirrus presence and heights (CTHs) using oblique stereo by the Multiangle Imaging SpectroRadiometer (MISR) with measurements from ground‐based cloud radar and lidar sensors at the Tropical Western Pacific (TWP) sites operated by the U.S. Department of Energy Atmospheric Radiation Measurement Program. Precise point‐wise comparisons, limited to only 195 coincident cases, showed that the total number of cirrus retrieved using oblique‐stereo analysis improved to 70% from 39% using the standard‐stereo technique. The stereo technique detects cloud with the highest contrast, which is often at lower altitude. The oblique‐stereo technique's efficiency depends on the thickness and number of underlying cloud layers. A histogram approach allowed similar regions to be compared statistically with many more samples and showed three distinct peaks at ≈13 km, 15 km, and 19 km related to deep convective clouds, tropical tropopause layer (TTL) cirrus, and overshooting convective clouds, respectively. Most differences between the satellite and ground‐based measurements resulted from a number of cases of invalid cloud comparisons (14%), blunders from edges and broken clouds (7%), low contrast stereo mismatches (4%), and under‐estimation of CTHs (3%). Overall, the oblique‐stereo analysis detected a cirrus‐top layer in 65% of all the valid coincident cases, mostly <1 km in thickness. The oblique‐stereo derived cirrus CTHs differed from the heights of cirrus‐top layers from ground‐based cloud radar and lidar by −0.5 ± 1.0 km, validating the MISR retrievals. This suggests global thin cirrus retrievals are possible with the oblique‐stereo technique after the screening of occasional blunders.
Statistical modeling of a former Arctic Ocean ice shelf complex using Antarctic analogies
Authors: Kirchner N. , Furrer R. , Jakobsson M. , Zwally H. J. , Robbins J. W.
Published: May 2013

Geophysical mapping and coring of the central Arctic Ocean seafloor provide evidence for repeated occurrences of ice sheet/ice shelf complexes during previous glacial periods. Several ridges and bathymetric highs shallower than present water depths of ∼1000m show signs of erosion from deep‐drafting (armadas of) icebergs, which originated from thick outlet glaciers and ice shelves. Mapped glacigenic landforms and dates of cored sediments suggest that the largest ice shelf complex was confined to the Amerasian sector of the Arctic Ocean during Marine Isotope Stage (MIS) 6. However, the spatial extent of ice shelves can not be well reconstructed from occasional groundings on bathymetric highs. Therefore, we apply a statistical approach to provide independent support for an extensive MIS 6 ice shelf complex, which previously was inferred only from interpretation of geophysical and geological data. Specifically, we assess whether this ice shelf complex comprises a likely source of the deep‐draft icebergs responsible for the mapped scour marks. The statistical modeling is based on exploiting relations between contemporary Antarctic ice shelves and their local physical environments and the assumption that Arctic Ocean MIS6 ice shelves scale similarly. Analyzing ice thickness data along the calving front of contemporary ice shelves, a peak over threshold method is applied to determine sources of deep‐drafting icebergs in the Arctic Ocean MIS6 ice shelf complex. This approach is novel to modeling Arctic paleoglacial configurations. Predicted extreme calving front drafts match observed deep‐draft iceberg scours if the ice shelf complex is sufficiently large.
Sources of terrigenous inputs to surface sediments of the Colville River Delta and Simpson's Lagoon, Beaufort Sea, Alaska
Authors: Schreiner Kathryn M. , Bianchi Thomas S. , Eglinton Timothy I. , Allison Mead A. , Hanna Andrea J. M.
Published: May 2013

The provenance of sediments and particulate organic carbon (POC) in the Colville River delta and adjacent Simpson's Lagoon, in the Alaskan Beaufort Sea, was investigated using a variety of bulk and molecular techniques, including stable and radiocarbon isotopes, neodymium isotopes, algal pigments, and lignin‐phenols. Additionally, stable carbon isotopes and lignin‐phenols were analyzed on four different density fractions from sediments. The Colville River, the largest river in North America with a watershed exclusively located in the high‐Arctic tundra, was an important source of terrestrial POC to the western edge of the Lagoon, shown by extremely old radiocarbon ages (fraction modern of 0.165 ± 0.001 close to the river mouth up to 0.418 ± 0.002 farther away). Stations without northern protective barrier islands had large amounts of marine POC input, and evidence of benthic microalgae was found in one area of the Lagoon (chlorophyll‐a concentration 35.0 µg gOC−1 in the high‐algal biomass area compared to 1 to 7 µg gOC−1 outside of it). Stations in the middle and eastern end of the Lagoon showed significant sediment input from coastal erosion (input of peat‐indicating non‐lignin‐phenols 0.079 mg (100mgOC)−1 in the eastern lagoon compared to 0.022 mg (100mgOC)−1 near the Colville delta), and on the eastern end of the Lagoon there was evidence of input of Mackenzie River POC, shown with neodymium isotopes and also COP. POC inputs derived from rivers, coastal erosion, and marine productivity were quantified using a ternary mixing model and showed that fluvial supply and coastal erosion were the dominant carbon sources to the Lagoon. This constitutes the first study of POC delivery by the Colville River into a nearshore region and illustrates that continued warming of the high Arctic tundra will likely lead to increased riverine POC delivery to this region of the world.
An Extremal Property of Turán Graphs, II
Authors: Tofts Spencer N.
Published: May 2013

Let denote Turán's graph—the complete 2‐partite graph on n vertices with partition sizes as equal as possible. We show that for all , the graph has more proper vertex colorings in at most 4 colors than any other graph with the same number of vertices and edges.
The use of X‐shaped cross‐link in posterior spinal constructs improves stability in thoracolumbar burst fracture: A finite element analysis
Authors: Alizadeh Mina , Kadir Mohammed Rafiq Abdul , Fadhli Miskon Mohd , Fallahiarezoodar Ali , Azmi Baharudin , Murali Malliga Raman , Kamarul Tunku
Published: May 2013

Posterior instrumentation is a common fixation method used to treat thoracolumbar burst fractures. However, the role of different cross‐link configurations in improving fixation stability in these fractures has not been established. A 3D finite element model of T11‐L3 was used to investigate the biomechanical behavior of short (2 level) and long (4 level) segmental spine pedicle screw fixation with various cross‐links to treat a hypothetical L1 vertebra burst fracture. Three types of cross‐link configurations with an applied moment of 7.5 Nm and 200 N axial force were evaluated. The long construct was stiffer than the short construct irrespective of whether the cross‐links were used (p < 0.05). The short constructs showed no significant differences between the cross‐link configurations. The XL cross‐link provided the highest stiffness and was 14.9% stiffer than the one without a cross‐link. The long construct resulted in reduced stress to the adjacent vertebral bodies and screw necks, with 66.7% reduction in bending stress on L2 when the XL cross‐link was used. Thus, the stability for L1 burst fracture fixation was best achieved by using long segmental posterior instrumentation constructs and an XL cross‐link configuration. Cross‐links did not improved stability when a short structure was used. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1447–1454, 2013
A Modified Technique of End‐to‐End Pancreaticojejunostomy With Transpancreatic Interlocking Mattress Sutures
Authors: Wang Min , Zhu Feng , Wang Xin , Tian Rui , Shi Chengjian , Shen Ming , Xu Meng , Han Juan , Luo Niannian , Qin Renyi
Published: May 2013

Background

Postoperative pancreatic fistula (POPF) represents the most important cause of morbidity after pancreaticoduodenectomy (PD) and contributes to prolonged hospitalization and increased mortality rates. This study presents a new technique, which involves end‐to‐end pancreaticojejunostomy with transpancreatic interlocking mattress sutures, and evaluates its safety and reliability.

Methods

From January 2011 to May 2012, 79 patients with periampullary malignancies underwent PD by using this modified technique, and the morbidity and mortality rates were calculated.

Results

In this study, all cases recovered well from PD. Four transpancreatic interlocking mattress sutures were performed in 79 patients. The median duration of surgery was 3.9 hr (range 3.1–6.8), and the median time to perform pancreaticojejunostomy was 15.3 min (range 9–24). Overall, morbidity occurred in 16 patients (22.3%), and the causes included upper gastrointestinal bleeding (n = 2), biliary fistula (n = 1), pulmonary infection (n = 1), delayed gastric emptying (n = 1), abdominal abscess (n = 1, caused by PF), wound infection (n = 3), arrhythmia or myocardial infarction (n = 3), urinary tract infection (n = 2), and POPF (n = 2, 2.53%). One patient had grade A POPF, one had grade B POPF, and none of them had grade C POPF. No death occurred during surgery.

Conclusion

The end‐to‐end pancreaticojejunostomy with transpancreatic interlocking mattress sutures is a simple, rapid, safe, and reliable technique with low POPF rate and low delayed massive hemorrhage rate. J. Surg. Oncol. 2013 9999:XX–XX. © 2013 Wiley Periodicals, Inc. J. Surg. Oncol. 2013;107:783–788. © 2013 Wiley Periodicals, Inc.
Surgery for Metastasis to the Pancreas: Is it Safe and Effective?
Authors: Niess Hanno , Conrad Claudius , Kleespies Axel , Haas Florian , Bao Qi , Jauch Karl‐Walter , Graeb Christian , Bruns Christiane J.
Published: May 2013

Background

Pancreatic metastases are rare and only sparse data exists on treatment options. After recent advances in pancreatic surgery, metastasectomies have become promising treatment alternatives.

Methods

Twenty‐six patients underwent pancreatic metastasectomy between 1991 and 2010 at our institution. Data was evaluated retrospectively.

Results

Renal cell carcinoma was the most common origin of pancreatic metastases (n = 16; 62%). Other primaries include gall bladder carcinoma, leiomyosarcoma, colon cancer (all n = 2), and others. The median time interval between primary tumor and pancreatic resection was 5.3 years [0–24]. Eleven pancreatic head resections (42%), fourteen distal pancreatectomies (54%), and one total pancreatectomy were performed (4%). The estimated 3‐ and 5‐year survival rates were 73.2% and 52.3%, respectively. The estimated median overall survival was 63 months (CI: 37.8–88.1 months). There' was no perioperative death. The complication rate and relaparotomy rate was 31% and 19%, respectively. Patients suffering from synchronous metastases at the time of pancreatic surgery had a statistically significant shorter median overall survival time (11 months vs. 64 months).

Conclusions

Despite the operative risk involved, we believe that pancreatic resection should be considered in selected patients with good performance status, stable disease and isolated pancreatic metastases. J. Surg. Oncol. 2013;107:859–864. © 2013 Wiley Periodicals, Inc.
Development of a new in‐vial standard gas system for calibrating solid‐phase microextraction in high‐throughput and on‐site applications
Authors: Gómez‐Ríos German A. , Reyes‐Garcés Nathaly , Pawliszyn Janusz
Published: May 2013

In this work, an innovative, reproducible, and reusable standard generator vial is presented. The standard generator vial consists of vacuum‐pump oil doped with McReynolds probes (benzene, 2‐pentanone, pyridine, nitropropane, 1‐pentanol, and n‐octane) mixed with a polystyrene‐divinylbenzene resin without functional groups. The evaluation of this vial was fully automated on a multifiber exchanger system and the extraction/desorption cycle, together with the programmed GC–qMS analysis, did not exceed 13 min. The results showed that after 160 extraction/injections cycles of the vial the relative SDs were smaller than 4% for all the standards. A randomized block design was used to evaluate the inter and intravial repeatability, and at 95% level of confidence nonstatistical differences among vials were found. Because of its compacted granular appearance this vial is easy to transport, and it is an ideal calibration standard for bench and field instruments and devices.
Black Marking and Smooth Surfaces
Authors: Ofer Ulrich
Published: May 2013

During the past 30 years, laser marking has become an established industry, facing both significant growth rates and the related consequences such as concentration and specialization.
New Systems for Laser Cladding
Authors: Lester Sam , Longfield Nick , Griffiths Justin , Cocker John , Staudenmaier Christian , Broadhead Gary
Published: May 2013

Components used in the manufacture of steel strip work in exceptionally aggressive environments and have to withstand service at high temperatures in corrosive atmospheres under mechanical wear and frequent and heavy impact loading. Conventionally, components that are subject to high wear or corrosion have often been manufactured from rich chemistry steels or hardfaced using submerged arc clad martensitic stainless steels to increase their campaign life and therefore maximise line throughput by extending maintenance intervals without any sacrifice to product quality.
Ring‐Opening Polymerization of Racemic β‐Butyrolactone Promoted by Salan‐ and Salen‐Type Yttrium Amido Complexes
Authors: Pappalardo Daniela , Bruno Massimo , Lamberti Marina , Pellecchia Claudio
Published: May 2013

A series of yttrium amido complexes bearing quadridentate binaphthyl‐bridged Schiff‐base salen‐like and diamine bisphenolate salan‐like ligands are synthesized and characterized. The complexes act as active initiators in the polymerization of rac‐β‐butyrolactone (rac‐BBL) under mild conditions. The obtained poly(3‐hydroxybutyrate) (PHBs) are syndiotactic enriched. 13C NMR spectroscopy microstructure analysis shows the probability of racemic linkages Pr to be up to 0.81. Statistical Bernoullian analysis evidences that a chain‐end mechanism of steric control operates for the salan‐like compound bearing cumyl substituents in the ortho position of the phenolate rings. The melting temperatures of the syndiotactic enriched PHBs are in the range 120–157 °C, depending on the degree of stereoregularity of the polymers.

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A Poly(vinyl alcohol)‐graft‐Copolyester: Synthesis of a Novel Graft Copolymer Containing Adamantane Moieties as Guest for Cyclodextrin
Authors: Stöhr Olesja , Winsberg Jan , Ritter Helmut
Published: May 2013

A novel graft copolymer is synthesized from commercially available poly(vinyl alcohol) using ring‐opening polymerization. For the polymerization reaction of novel brush‐like poly(vinyl alcohol)‐graft‐poly(ϵ‐caprolactone‐co‐(3‐/7‐(prop‐2‐ynyl)oxepan‐2‐one) 5 Sn(Oct)2 is used as a catalyst. The formation of the graft copolymer is confirmed by 1H NMR, 13C NMR, and Fourier transform infrared (FTIR) spectroscopy. Furthermore, the modification of the novel synthesized graft copolymer via a “click” reaction to implement adamantane groups is described. The success of the “click” reaction is proven by 1H NMR spectroscopy and visualized by decomplexation of cyclodextrin with included phenolphthalein.

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Development of New Atom Transfer Radical Polymerization System by Iron (III)‐Metal Salts Without Using any External Initiator and Reducing Agent
Authors: Khan Mohd Yusuf , Chen Xiangxiong , Lee Seung Woo , Noh Seok Kyun
Published: May 2013

Atom transfer radical polymerization (ATRP) catalyzed by high oxidation state metal salts of FeX3 is developed for the first time in the absence of both external initiator and reducing agent. Methyl methacrylate (MMA) and styrene are polymerized successfully using FeX3/Phosphorous ligands with well‐controlled molecular weight distributions (=1.5). The molecular weight of the polymers increases with monomer consumption with the progress of time and the polymerization behaviors show a decent ATRP trend. Activators and initiators are suggested to generate in situ by the addition reaction of MMA and one equivalent of FeX3. The PMMA synthesized from without‐initiator system is characterized by 1H, 13C and DEPT (distortionless enhancement by polarization transfer nuclear magnetic resonance) nuclear magnetic resonance spectroscopy. Chain extension and copolymerization experiments prove the livingness of the obtained polymer.

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The Babinski‐2 sign in hemifacial spasm
Authors: Pawlowski Matthias , Gess Burkhard , Evers Stefan
Published: May 2013

Background

Hemifacial spasm is a common movement disorder. Differential diagnosis relies on clinical examination and is often difficult. The Babinski‐2 sign is an underrecognized physical sign specifically found in patients with hemifacial spasm, although its prevalence and usefulness are a matter of debate.

Methods

We examined 35 patients with hemifacial spasm prospectively for the presence of the Babinski‐2 sign. We evaluated its correlation with severity of hemifacial spasm, concomitant facial nerve paralysis, and response to botulinum toxin. Twelve patients with blepharospasm served as the control population.

Results

The data for the Babinski‐2 sign demonstrated high prevalence (86%), high specificity (100%), and high interrater reliability (92%).

Conclusions

Increased awareness of the Babinski‐2 sign may aid diagnosis and potentially prompt earlier initiation of appropriate treatment. © 2013 Movement Disorder Society
Metabolomic fingerprint in patients at high risk of cardiovascular disease by cocoa intervention
Authors: Llorach Rafael , Urpi‐Sarda Mireia , Tulipani Sara , Garcia‐Aloy Mar , Monagas Maria , Andres‐Lacueva Cristina
Published: May 2013

Scope

Metabolomics approach is focused on identifying all metabolites present in a biological sample (metabolome). Consumption of cocoa products has been related to health benefits including positive effect on cardiovascular health.

Methods and results

Twenty volunteers were included in this randomized, crossover, and controlled clinical trial. After a 2‐wk washout period, subjects received 40 g/day of cocoa powder with 500 mL skimmed milk (cocoa with skimmed milk intervention) or 500 mL/day of skimmed milk (skimmed milk intervention) for 4‐wk. Urine (24 h) samples were collected at baseline and after each intervention and were analyzed by HPLC‐hybrid quadrupole TOF in negative and positive ionization modes followed by multivariate analysis. This analysis revealed a marked separation between the cocoa with skimmed milk intervention and skimmed milk intervention and baseline periods. Thirty‐nine compounds linked with cocoa intake, including alkaloid metabolites, polyphenol host and gut microbial metabolites (hydroxyphenylvalerolactones and hydroxyphenylvaleric acids), diketopiperazines and N‐phenylpropenoyl‐l‐amino acids were identified. In the case of endogenous metabolites, putative identifications suggested that metabolites linked with carnitine metabolism and sulfation of tyrosine were decreased by the consumption of cocoa.

Conclusion

LC‐MS metabolomics strategy allows the defining of a complex metabolic profile derived from cocoa phytochemicals. Likewise, the identification of endogenous markers could lead to new hypotheses to unravel the relationship between cocoa intake and cardiovascular diseases.
Magnetic susceptibility induced white matter MR signal frequency shifts—experimental comparison between Lorentzian sphere and generalized Lorentzian approaches
Authors: Luo J. , He X. , Yablonskiy D. A.
Published: May 2013

Purpose

The nature of the remarkable phase contrast in high‐field gradient echo MRI studies of human brain is a subject of intense debates. The generalized Lorentzian approach (He and Yablonskiy, Proc Natl Acad Sci USA 2009;106:13558–13563) provides an explanation for the anisotropy of phase contrast, the near absence of phase contrast between white matter and cerebrospinal fluid, and changes of phase contrast in multiple sclerosis. In this study, we experimentally validate the generalized Lorentzian approach.

Theory and Methods

The Generalized Lorentzian Approach suggests that the local contribution to frequency shifts in white matter does not depend on the average tissue magnetic susceptibility (as suggested by Lorentzian sphere approximation), but on the distribution and symmetry of magnetic susceptibility inclusions at the cellular level. We use ex vivo rat optic nerve as a model system of highly organized cellular structure containing longitudinally arranged myelin and neurofilaments. The nerve's cylindrical shape allowed accurate measurement of its magnetic susceptibility and local frequency shifts.

Results

We found that the volume magnetic susceptibility difference between nerve and water is −0.116 ppm, and the magnetic susceptibilities of longitudinal components are −0.043 ppm in fresh nerve, and −0.020 ppm in fixed nerve.

Conclusion

The frequency shift observed in the optic nerve as a representative of white matter is consistent with generalized Lorentzian approach but inconsistent with Lorentzian sphere approximation. Magn Reson Med 71:1251–1263, 2014. © 2013 Wiley Periodicals, Inc.
Search games on networks with travelling and search costs and with arbitrary searcher starting points
Authors: Baston Vic , Kikuta Kensaku
Published: May 2013

The authors analyze two‐person zero‐sum search games of the following type. Play takes place on a network; the hider must choose a node and remain there while the searcher can choose the node at which he starts. To detect the hider, the searcher needs to conduct a search at the node chosen by the hider. Searching a node involves a cost which can vary from node to node. In addition to the search costs, the searcher also incurs travelling costs represented by distances on the edges. The costs are known to both players and the searcher wants to minimize his total costs. An upper bound for the value of the game is obtained and a lower bound when the network has all its edge lengths the same. Restricting attention to networks which have all their edges of the same length, the upper, and lower bounds are shown to coincide for some networks including Hamiltonian ones. Some results for the star and line networks are also given. © 2013 Wiley Periodicals, Inc. NETWORKS, 2013
Predicting Variation in Funding for International Nongovernmental Organizations Following Three External Events
Authors: Kerlin Janelle A.
Published: May 2013

This article analyzes the impact of a number of external events on major funding streams for U.S.‐based international nongovernmental organizations (INGOs) to inform government and organizational policy relevant to INGO managers. The first years of the twenty‐first century saw three events that influenced INGO financing: the 2001 economic downturn, the shift in U.S. foreign policy following the terrorist attacks of September 11, 2001, and the 2004 East Asian tsunami. Drawing on data from the National Center for Charitable Statistics, this study provides large dataset analysis of the finances of U.S.‐based INGOs during the 2001–05 period. As predicted, the analysis finds that these outside events appeared to affect the different funding streams of INGOs in different ways, with variation seen across type of INGO program and geographic focus. These findings help inform policy for managers, funders, and policymakers in the U.S. international community.
Abuse victimization in childhood or adolescence and risk of food addiction in adult women
Authors: Mason Susan M. , Flint Alan J. , Field Alison E. , Austin S. Bryn , Rich‐Edwards Janet W.
Published: May 2013

Objective

Child abuse appears to increase obesity risk in adulthood, but the mechanisms are unclear. This study examined the association between child abuse victimization and food addiction, a measure of stress‐related overeating, in 57,321 adult participants in the Nurses' Health Study II (NHSII).

Design and Methods

The NHSII ascertained physical and sexual child abuse histories in 2001 and current food addiction in 2009. Food addiction was defined as ≥3 clinically significant symptoms on a modified version of the Yale Food Addiction Scale. Confounder‐adjusted risk ratios (RRs) and 95% confidence intervals (CIs) were estimated using modified Poisson regression.

Results

Over 8% of the sample reported severe physical abuse in childhood, while 5.3% reported severe sexual abuse. Eight percent met the criteria for food addiction. Women with food addiction were 6 U of BMI heavier than women without food addiction. Severe physical and severe sexual abuse were associated with roughly 90% increases in food addiction risk (physical abuse RR = 1.92; 95% CI: 1.76, 2.09; sexual abuse RR = 1.87; 95% CI: 1.69, 2.05). The RR for combined severe physical abuse and sexual abuse was 2.40 (95% CI: 2.16, 2.67).

Conclusions

A history of child abuse is strongly associated with food addiction in this population.
Late Pliocene to early Pleistocene changes in the North Atlantic Current and suborbital‐scale sea‐surface temperature variability
Authors: Friedrich Oliver , Wilson Paul A. , Bolton Clara T. , Beer Christopher J. , Schiebel Ralf
Published: May 2013

The strength and latitudinal position of the North Atlantic Current, NAC, determines the position of the Arctic front and heat transport to the high northern latitudes with potentially important consequences for Northern Hemisphere glaciation. A southward shift in the NAC and reduced poleward heat transport is hypothesized to have triggered the last major climate transition in Earth's history—late Pliocene intensification of Northern Hemisphere glaciation (iNHG). In turn, iNHG is hypothesized to have led to the amplification of climate variability on suborbital time scales. To date, however, only a handful of adequately resolved records are available to test these two hypotheses. Here we present a new late Pliocene to earliest Pleistocene record from Integrated Ocean Drilling Program Site U1313 (North Atlantic, 41°N; 2.9 to 2.4 Ma). We use Mg/Ca‐derived paleotemperature records in planktic foraminiferal calcite to investigate changes in summer sea‐surface temperatures (SST) on orbital and suborbital time scales. Our results call into question the suggestion that significant weakening and/or southward shift of the NAC served as a trigger for Northern Hemisphere cooling and intensified continental ice sheet growth across iNHG. In contrast to the late Pleistocene, during iNHG, we find that the position of the NAC and Arctic Front probably lay well to the north of Site U1313 and that the amplitude of suborbital SST variability did not change on glacial‐interglacial time scales. Conservative estimates of Late Pliocene to earliest Pleistocene interglacial summer SSTs in our record are up to 3°C warmer than present, while glacial summer SSTs are only 2°C to 3°C cooler. In fact, our interglacial summer SSTs are remarkably similar to those of the mid‐Pliocene. Our findings indicate that iNHG must have involved amplifying feedback mechanisms that are tightly coupled to ice sheet growth but that these processes were insufficiently developed by the late Pliocene/earliest Pleistocene to have triggered large amplitude changes in suborbital climate in the midlatitude North Atlantic.
Selective interfacial localization in conducting polycaprolactam/ethylene vinyl acetate/carbon black composites
Authors: Sinha S.K. , Dubey K.A. , Grover V. , Sastry P. , Bhardwaj Y.K. , Panicker L. , Tyagi A.K. , Mahanwar P.A. , Bambole V.A.
Published: May 2013

Unusual electrical conductivity was demonstrated by ethylene vinyl acetate/polycaprolactam/carbon black (CB) composites. The critical exponent value was 1.2 ± 0.2 for ternary composites and was greater than 2.0 for the binary composites, indicating two‐dimensional electrical conduction in ternary composites. The ternary composites also showed inverted U‐shaped conductivity curves when CB weight fraction was greater than 10 wt%. However, at 10 wt% CB, a discontinuous conductivity curve showing conductivity only when polycaprolactam content was greater than 50% was observed, suggesting substantial variation in the interfacial characteristics with the change in the blend composition. Small‐angle X‐ray scattering studies pointed out that ternary composites can be viewed as a two‐phase system with sharp boundaries, and that interface layer in the composites does not exist. Differential scanning calorimetry studies suggested composition dependent variation in the crystallinity of polycaprolactam phase, partially contributing to the increase in the composites' conductivity at higher polycaprolactam fractions. POLYM. COMPOS., 34:912–919, 2013. © 2013 Society of Plastics Engineers
Preparation and capacitive performances of PEDOT/indigo carmine composite hydrogel
Authors: Han Yongqin , Shen Mingxia , Zhu Jiajia , Wu Ying , Zhang Xiaogang
Published: May 2013

In this article, indigo carmine (IC) was introduced into poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT‐PSS) hydrogel by in situ polymerization to prepare PEDOT/IC composite hydrogel. The structural characterization of PEDOT/IC composite hydrogel was analyzed by Fourier‐transform infrared spectroscopy (FTIR), UV–vis spectroscopy, X‐Ray diffraction (XRD), and Scanning electron microscopy (SEM). The results indicated that IC was successfully introduced into PEDOT‐PSS hydrogel. Electrochemical performances were investigated by cyclic voltammetry, galvostatic charge‐discharge, and electrochemical impedance technology. The specific capacitance of PEDOT‐PSS hydrogel was efficiently increased by the introduction of IC. The specific capacitance of PEDOT‐PSS hydrogel increased first and then decreased with the increase of the concentration of IC. The specific capacitance of PEDOT‐PSS hydrogel was increased from 38F/g to a maximum value of 123F/g (current density = 0.5 A/g) when the concentration of IC reached 5 mM. On the basis of cycle‐life tests, the capacitance retention of about 68% for the PEDOT/IC composite hydrogel after 5000 cycles suggested a high cycle stability of PEDOT/IC composite hydrogel and its potential as an electrode material for supercapacitor applications. POLYM. COMPOS., 34:989–996, 2013. © 2013 Society of Plastics Engineers
Global gene expression analysis of amniotic fluid cell‐free RNA from recipient twins with twin–twin transfusion syndrome
Authors: Hui Lisa , Wick Heather C. , Moise Kenneth J. , Johnson Anthony , Luks Francois , Haeri Sina , Johnson Kirby L. , Bianchi Diana W.
Published: May 2013

Objective

The objective of this study was to understand the biological pathways involved in twin–twin transfusion syndrome (TTTS) by performing global gene expression analysis of amniotic fluid (AF) cell‐free RNA.

Methods

A prospective whole transcriptome microarray study analyzing cell‐free RNA in AF from TTTS recipient twins and singleton controls was carried out. Significantly differentially regulated genes in TTTS cases (N = 8) versus matched controls (N = 8) were identified and pathways analyses performed. Significant gene expression differences between stage II TTTS recipients (N = 5) and stage III TTTS recipients with abnormal Doppler measurements (N = 5) were also analyzed.

Results

Analysis of paired data from TTTS cases and controls revealed differential expression of 801 genes, which were significantly enriched for neurological disease and cardiovascular system pathways. We also identified cardiovascular genes and pathways associated with the presence of critically abnormal Doppler measurements in stage III TTTS recipients.

Conclusions

This study provides the first transcriptome‐wide data on the impact of TTTS on fetal development. Our results show that gene expression involving neurological and cardiovascular pathways are altered in recipient fetuses prior to surgical treatment. This has relevance for the origins of long‐term complications seen in survivors and for the development of future fetal biomarkers. © 2013 John Wiley & Sons, Ltd.
Schillernde Spinnennetze
Authors: Schlichting H. Joachim , Suhr Wilfried
Published: May 2013

Im Gegenlicht schillert ein Spinnennetz in vielfältigen Farben, besonders der Fangfaden. Die Farben verdanken sich der Periodizität der Klebetröpfchen auf diesem Faden. Dadurch stellt er ein lineares optisches Gitter dar, das dieses komplexe, irisierende Beugungsmuster hervorruft. Mit leicht über das Spinnennetz schweifendem Blick lässt es sich abtasten. Laborexperimente schlüsseln auf, welchen Beitrag die jeweiligen Beugungselemente des Fangfadens dazu liefern.
Characterization of PAX‐21 Insensitive Munition Detonation Residues
Authors: Walsh Michael R. , Walsh Marianne E. , Taylor Susan , Ramsey Charles A. , Ringelberg David B. , Zufelt Jan E. , Thiboutot Sonia , Ampleman Guy , Diaz Emmanuela
Published: May 2013

Insensitive high explosives are being used in military munitions to counteract unintended detonations during storage and transportation. These formulations contain compounds such as 2,4‐dinitroanisole (DNAN) and 3‐nitro‐1,2,4‐triazol‐5‐one (NTO), which are less sensitive to shock and heat than conventional explosives. We conducted a series of four tests on snow‐covered ice utilizing 60‐mm mortar cartridges filled with 358 g of PAX‐21, a mixture of RDX, DNAN, and ammonium perchlorate. Rounds were detonated high‐ and low‐order using a fuze simulator to initiate detonation. Blow‐in‐place (BIP) operations were conducted on fuzed rounds using an external donor charge or a shaped‐charge initiator. Results indicate that 0.001 % of the original mass of RDX and DNAN were deposited during high‐order detonations, but up to 28 % of the perchlorate remained. For the donor block BIPs, 1 % of the RDX and DNAN remained. Residues masses for these operations were significantly higher than for conventional munitions. Low‐order detonations deposited 10–15 % of their original explosive filler in friable chunks up to 5.2 g in mass. Shaped‐charge BIPs scattered 15 % of the filler and produced chunks up to 15 g. Ammonium perchlorate residue masses were extremely high because of the presence of large AP crystals, up to 400 μm in the recovered particles.