bluuebunny/crossref_metadata_2025 huggingface dataset:
A population‐based comparison of second primary cancers in Germany and Sweden between 1997 and 2006: clinical implications and etiologic aspects
Authors: Liu Hao , Hemminki Kari , Sundquist Jan , Holleczek Bernd , Katalinic Alexander , Emrich Katharina , Jansen Lina , Brenner Hermann ,   The GEKID Cancer Survival Working Group
Published: August 2013

Second primary cancer (SPC) has become an increasing concern in cancer survivorship. Patterns of SPCs in different populations may offer clinical implications and research priorities into SPCs. This study is devoted to compare the occurrences and rank correlations of SPCs between Germany and Sweden. Patients diagnosed with 10 common first primaries between 1997 and 2006 from the Swedish Family‐Cancer Database and 10 German cancer registries were included in this population‐based study. Spearman's rank correlation coefficients were used to evaluate the strength of the relationship of SPCs between the German and Swedish datasets. Spearman's rank correlation coefficients suggested a strong positive correlation between the German and Swedish datasets based on the ranks of thirty possible SPCs after all selected first cancers. This was also true when we compared the rankings and proportions of the five most common SPCs after site‐specific first primaries between the two populations. For kidney cancer, non‐Hodgkin's lymphoma, and leukemia the components of the five most common SPCs was exactly the same. Also, the ranking and the proportions for the three most common SPCs (i.e., colorectal, bladder, and lung cancers) after prostate cancer were identical in the two populations, as were those after most other primary cancers. The strikingly consistent patterns of SPCs in the two populations provide excellent opportunities for joint studies and they also suggest that many underlying reasons for SPC may have universal and tangible causes that await mechanistic dissection.
Helex device closure of multiple atrial septal defects
Authors: Mehta Smita , Hill James A. , Qureshi Athar M. , Latson Larry A. , Prieto Lourdes R.
Published: August 2013

Objectives : To describe the effectiveness of the Helex Septal Occluder (HSO) to close multiple atrial septal defects (mASDs). Background : Limited information is available describing closure of mASDs with the HSO. Methods : A total of 28 patients who underwent closure of mASDs with the HSO were identified by retrospective review of our catheterization database between 2001 and 2012. Procedural details and follow up information were collected. Results : Median age was 19.2 years, median weight 48 kg, with 10 (36%) patients weighing <25 kg. Indication for closure was RV enlargement (RVE) in all patients and additionally neurologic events occurred in 3/28 (11%). Median stop‐flow diameter for the largest ASD was 14 (4–23) mm. One HSO was implanted in 21/28 (75%), 2 in 6/28 (21%), and 3 in 1/28 (4%). One embolization and one transient arrhythmia occurred with no sequelae. Immediate residual shunt was absent in 5/28 (18%), trivial in 15/28 (54%), small in 6/28 (21%), and moderate in 2/28 (7%). Of the 25 patients with ≥6 months follow‐up (median 53 months), residual shunt was absent in 13/25 (52%), trivial in 5/25 (20%), and small in 7/25 (28%). RVE resolved in all but one patient with no other associated lesions and ≥6 months of follow‐up. No patient with prior neurological event had recurrence at last follow‐up. Conclusions : We conclude that closure of mASDs with ≥1 HSO is effective with a low complication rate. The ability of HSO devices to overlap or sandwich each other may facilitate safe implantation of multiple devices in smaller patients. © 2013 Wiley Periodicals, Inc.
Postdilatation for treatment of perivalvular aortic regurgitation after transcatheter aortic valve implantation
Authors: Lasa Garikoitz , Gaviria Koldo , Sanmartín Juan C. , Telleria Miren , Larman Mariano
Published: August 2013

Objectives

The study is made to describe the efficacy and safety of balloon postdilatation (BPD) for the treatment of residual aortic regurgitation (RAoR) after transcatheter aortic valve implantation (TAVI).

Methods and Results

A single‐center observational study is made with 157 consecutive patients accepted to TAVI. The patients were divided into two groups (no BPD‐period and BPD‐period). Before BPD, RAoR ≥ 2 was seen in 25% of the patients in group 1 and in 29% of the patients in group 2 (P ≥ 0.593). BPD was carried out in 95% (n = 21) of the patients in group 2 with RAoR ≥ 2. Regurgitation improved one grade in 68% of the cases (n = 15), 2 grades in 14% (n = 3), and remained without change in 18% (n = 4). RAoR < 2 was achieved in 91% (n = 73) of the patients in group 2 versus 75% (n = 58) in group 1 (RR = 0.35, 95% CI 0.16–0.80, P = 0.013). We recorded no aortic ring ruptures, damage to the device or displacements. Slight central regurgitation not present before BPD was registered in one case.

Conclusions

BPD offers a very good safety profile and reduces RAoR in a large percentage of cases. BPD should be considered for the treatment of moderate to severe RAoR following TAVI. © 2013 Wiley Periodicals, Inc.
Activation of Isocyanates and Carbon Dioxide by a Monomeric Aluminium Hydrazide as an Active Lewis Pair
Authors: Hengesbach Frank , Jin Xing , Hepp Alexander , Wibbeling Birgit , Würthwein Ernst‐Ulrich , Uhl Werner
Published: August 2013

The monomeric aluminium hydrazide H10C5NN(AltBu2)Ad (4; Ad=adamantyl, NC5H10=piperidinyl) was obtained in high yield by hydroalumination of the corresponding hydrazone derivative 1. Compound 4 has a strained AlN2 heterocycle formed by a donor–acceptor bond between the β‐nitrogen atom of the hydrazide group and the aluminium atom. Opening of this bond resulted in the formation of an active Lewis pair that was able to cooperatively activate carbon dioxide or isocyanates. Insertion of the heterocumulenes into the AlN bond selectively afforded a carbamate and two urea derivatives in high yield. In the first step, phenyl isocyanate gave the adduct 6, which has the oxygen atom coordinated to the aluminium atom and its central carbon atom bound to the nitrogen atom of the piperidine moiety. Adduct 6 represents a reasonable intermediate state for these activation processes. The applicability of hydroaluminated compounds, such as 4, in organic synthesis was demonstrated by the reaction with an imidoyl chloride, which gave the corresponding amidrazone derivative 9.
Diffusionseffekte in der Magnetresonanztomographie – Eine kleine Übersicht bekannter und weniger bekannter Effekte
Authors: Nestle Nikolaus , Gädke Achim
Published: August 2013

Die Rolle von Diffusionseffekten in der Magnetresonanztomographie (MRT) ist vielfältig. In diesem Beitrag wird ein kurzer Überblick darüber gegeben, wie sich Diffusionseffekte direkt oder indirekt auf den Kontrast von MR‐Bildern auswirken können. Besondere Aufmerksamkeit wird dabei dem Wechselspiel zwischen Diffusion und longitudinaler Magnetisierung in dünnen angeregten Schichten gewidmet. Hierzu werden Experimente vorgestellt, wie sich eine periodische Anregung auf die messbare Signalamplitude in Schichten mit Dicken im Bereich von einigen μm auswirkt. Hierbei konnten Signalerhöhungen um etwa einen Faktor 100 beobachtet werden. Die untersuchten Phänomene sind von Bedeutung für den Kontrast und das Signal/Rausch‐Verhältnis in NMR‐Mikrotomographie‐Experimenten und bei einigen Ansätzen für die NMR‐Kraftmikroskopie.
Caseous Calcification of the Mitral Annulus: A Review
Authors: Elgendy Islam Y. , Conti C. Richard
Published: August 2013

Caseous calcification of the mitral annulus (CCMA) is a rare variant of mitral annular calcification (MAC). Since most cardiologists are unfamiliar with CCMA, it is commonly misdiagnosed as an abscess, tumor or infective vegetation on the mitral valve. In most cases, conservative management for this lesion is sufficient. In this review, we will discuss the various aspects of this condition and illustrate the gross and histologic pathology as well as various imaging modalities (Ultrasound, Computed tomography, Cardiac Magnetic resonance) to assess this unusual cardiac mass.
Distribution and functional expression of Kv4 family α subunits and associated KChIP β subunits in the bed nucleus of the stria terminalis
Authors: Rainnie Donald G. , Hazra Rimi , Dabrowska Joanna , Guo Ji‐Dong , Li Chen Chen , Dewitt Sarah , Muly E. Chris
Published: August 2013

Regulation of BNSTALG neuronal firing activity is tightly regulated by the opposing actions of the fast outward potassium current, IA, mediated by α subunits of the Kv4 family of ion channels, and the transient inward calcium current, IT. Together, these channels play a critical role in regulating the latency to action potential onset, duration, and frequency, as well as dendritic back‐propagation and synaptic plasticity. Previously we have shown that Type I–III BNSTALG neurons express mRNA transcripts for each of the Kv4 α subunits. However, the biophysical properties of native IA channels are critically dependent on the formation of macromolecular complexes of Kv4 channels with a family of chaperone proteins, the potassium channel‐interacting proteins (KChIP1–4). Here we used a multidisciplinary approach to investigate the expression and function of Kv4 channels and KChIPs in neurons of the rat BNSTALG. Using immunofluorescence we demonstrated the pattern of localization of Kv4.2, Kv4.3, and KChIP1–4 proteins in the BNSTALG. Moreover, our single‐cell reverse‐transcription polymerase chain reaction (scRT‐PCR) studies revealed that mRNA transcripts for Kv4.2, Kv4.3, and all four KChIPs were differentially expressed in Type I–III BNSTALG neurons. Furthermore, immunoelectron microscopy revealed that Kv4.2 and Kv4.3 channels were primarily localized to the dendrites and spines of BNSTALG neurons, and are thus ideally situated to modulate synaptic transmission. Consistent with this observation, in vitro patch clamp recordings showed that reducing postsynaptic IA in these neurons lowered the threshold for long‐term potentiation (LTP) induction. These results are discussed in relation to potential modulation of IA channels by chronic stress. J. Comp. Neurol. 522:609–625, 2014. © 2013 Wiley Periodicals, Inc.
A compensated PID active queue management controller using an improved queue dynamic model
Authors: Kahe Ghasem , Jahangir Amir Hossein , Ebrahimi Behrouz
Published: August 2013

Beside the major objective of providing congestion control, achieving predictable queuing delay, maximizing link utilization, and robustness are the main objectives of an active queue management (AQM) controller. This paper proposes an improved queue dynamic model while incorporating the packet drop probability as well. By applying the improved model, a new compensated PID AQM controller is developed for Transmission Control Protocol/Internet Protocol (TCP/IP) networks. The non‐minimum phase characteristic caused by Padé approximation of the network delay restricts the direct application of control methods because of the unstable internal dynamics. In this paper, a parameter‐varying dynamic compensator, which operates on tracking error and internal dynamics, is proposed to not only capture the unstable internal dynamics but also reduce the effect of uncertainties by unresponsive flows. The proposed dynamic compensator is then used to design a PID AQM controller whose gains are obtained directly from the state‐space representation of the system with no further gain tuning requirements. The packet‐level simulations using network simulator (ns2) show the outperformance of the developed controller for both queuing delay stability and resource utilization. The improved underlying model leads also to the faster response of the controller. Copyright © 2013 John Wiley & Sons, Ltd.
Versatile Supramolecular Coordination Behaviour of a Bis(bidentate) Tetraphosphane
Authors: Strabler Christof , Ortner Teresa , Prock Johannes , Granja Alvaro , Gutmann Rene , Kopacka Holger , Müller Thomas , Brüggeller Peter
Published: August 2013

The bis(bidentate) phosphane cis,trans,cis‐1,2,3,4‐tetrakis(diphenylphosphanyl)cyclobutane (dppcb) has been used for the synthesis of supramolecular complexes, so‐called dyads and triads. Depending on the monometallic precursor compound [Ru(bpy)2(dppcb)](PF6)2 or [Ru(bpy)2(cis‐dppcbO2)](PF6)2 [bpy = 2,2′‐bipyridine, cis‐dppcbO2 = cis,trans,cis‐1,2‐bis(diphenylphosphanoyl)‐3,4‐bis(diphenylphosphanyl)cyclobutane], [Ru(bpy)2(dppcb)NiBr2](PF6)2 (1) or ΔΛ/ΛΔ‐[{Ru(bpy)2(cis‐dppcbO2)}2NiBr](PF6)5 (2) is exclusively formed in good yield by reaction with [NiBr2(DME)] (DME = dimethoxyethane). The versatile coordination behaviour of dppcb compared with that of cis‐dppcbO2 is confirmed by cis,trans,cis‐2,3‐bis(diphenylphosphanoyl)‐1,4‐bis(diphenylphosphanyl)cyclobutane (2,3‐trans‐dppcbO2, 4). Although two dppcb ligands coordinated simultaneously to a PdII centre cannot produce a square‐planar PdP4 core, the reaction of two equivalents of 4 with [Pd(CH3CN)4](BF4)2 exclusively leads to meso‐(MMMP/MPPP)‐[Pd(2,3‐trans‐dppcbO2‐P,P′)2](BF4)2 (3). This means that trans configurations of coordinating 2,3‐trans‐dppcbO2 with respect to the cyclobutane rings allow the formation of this PdP4 moiety. However, in the case of 4 it is also possible to obtain [PdCl2(2,3‐trans‐dppcbO2‐P,P′)] (5) in excellent yield by using [PdCl2(COD)] (COD = cyclooctadiene). In 5, only one ligand 4 is attached to the PdII centre, and a trans configuration of 4 within the five‐membered chelate ring can again be seen. All solid‐state structures 1–5 have been determined by single‐crystal X‐ray structure analysis. The corresponding solution structures are in agreement with these solid‐state structures and have been authenticated by multinuclear NMR spectroscopy, FAB and MALDI‐TOF‐MS measurements, UV/Vis spectroscopy and cyclic voltammetry. In the case of 2, the emission and lifetime properties of the excited state indicate that triads such as 2 could be suitable catalysts for the reductive part of water splitting.
Synthesis and Supramolecular Architectures of Dinuclear Metallacyclic Silver(I) and Zigzag‐Chain Copper(II) Complexes Bearing 2,6‐Pyridinediylbis(3‐pyridinyl)methanone
Authors: Wan Chong‐Qing , Al‐Thabaiti Shaeel A. , Chen Xu‐Dong , Mak Thomas C. W.
Published: August 2013

The reaction of 2,6‐pyridinediylbis(3‐pyridinyl)methanone (abbreviated as L) with various silver(I) salts yielded a series of complexes, namely, [Ag2(L)2](ClO4)2 (1), {[Ag2(L)2](ClO4)2}∞ (2), {[Ag2(L)2](NO3)2}∞ (3), {[Ag2(L)2](C2F5CO2)2}∞ (4), {[Ag2(L)2](C3F7CO2)2}∞ (5), and {[Ag2(L)2](O2CC3F6CO2)·2H2O}∞ (6), which exhibit a common dinuclear metallacyclic [Ag2(L)2]2+ skeleton that involves linear‐dicoordinate AgI and μ2‐N,N‐bridging L. Complex 2 is a polymorph of 1 obtained by the solvent‐medium tuning effect, and it has an {[Ag2(L)2]2+}∞ infinite‐chain structure. In complexes 3–6, the argentophilic interaction plays an important role in connecting the [Ag2(L)2]2+ units to form a similar {[Ag2(L)2]2+}∞ chain structure to that in 2, although the counteranions are markedly different. The copper(II) complex {[Cu2(CH3CO2)4(L)]·2H2O}∞ (7) exhibits a zigzag‐chain structure composed of an alternating arrangement of L and the Cu2(CH3CO2)4 paddlewheel cluster. In the supramolecular architectures of 1–7, the counteranions engage in multiple noncovalent interactions, and the presence of unusual types such as O/F(anion)···π, O/F(anion)···C=O, and C=O···π are noted and discussed.
Solution‐Phase Synthesis of Short Oligo‐2′‐deoxyribonucleotides by Using Clustered Nucleosides as a Soluble Support
Authors: Kungurtsev Vyacheslav , Laakkonen Jouni , Molina Alejandro Gimenez , Virta Pasi
Published: August 2013

5′‐O‐(4,4′‐Dimethoxytrityl)thymidine was attached to a pentaerythrityl‐derived core, and the resulting tetravalent nucleoside cluster and the next dendritic generations served as a soluble support for the synthesis of short oligo‐2′‐deoxyribonucleotides in solution. Couplings using a small excess (1.5 equiv. per 5′‐OH group) of the standard phosphoramidite building blocks proved efficient, and the products could be purified by quantitative precipitation from methanol. Ammonolysis released nearly homogeneous oligonucleotides (CCT, GCT, ACT, and AGCCT) in high yields.
Self‐Referencing Background Correction Method for Voltammetric Investigation of Reversible Redox Reaction
Authors: Ciepiela Filip , Lisak Grzegorz , Jakubowska Małgorzata
Published: August 2013

This paper presents a novel fully automated background correction method, which internally validates its results. The method requires a set of voltammograms recorded for calibration with different sensitivities but offers reproducibility, high precision and accuracy. In this paper the results obtained with the use of the proposed algorithm were verified by the processing of both simulated and experimentally registered signals. In both cases recovery and confidence intervals were very satisfactory.
Electrochemical Oxidation Mechanism of Ethidium Bromide at a Glassy Carbon Electrode
Authors: Oliveira Severino Carlos B. , Nascimento Valberes B.
Published: August 2013

The electrochemical behavior of ethidium bromide (EtBr) on a glassy carbon electrode (GCE) was studied by cyclic, square wave and differential pulse voltammetry over a wide pH interval. The results revealed that the oxidation mechanism of EtBr is an irreversible and adsorption‐controlled electrode process that occurs in two consecutives steps. The first step is pH‐dependent and occurs at the amino group in the C8 position with the formation of ortho‐ and para‐quinone derivatives, while the second step is pH‐independent and occurs at the amino group in the C3 position. A square wave method for quantitative determination of EtBr is also proposed.
Towards Graphane Applications in Security: The Electrochemical Detection of Trinitrotoluene in Seawater on Hydrogenated Graphene
Authors: Seah Tzu Hui , Poh Hwee Ling , Chua Chun Kiang , Sofer Zdeněk , Pumera Martin
Published: August 2013

With greater security and humanitarian concerns, the pressing need to develop fast and sensitive point‐of‐care explosives detectors has never been more pronounced. Electrochemical detectors facilitate accurate and swift detection of these explosive traces to provide opportunities for preemptive measures. Sensitivity of the electrode material is one of the many important factors in the development of an effective and efficient electrochemical detector. Herein, we present study on the applicability of graphene and hydrogenated graphene for the detection of TNT in seawater. Graphene was found to display a higher sensitivity than hydrogenated graphene and could be an ideal material for the detection of TNT in seawater. This is likely due to the fact that graphene contains a larger amount of aromatic rings than hydrogenated graphene, enabling larger preconcentration. These finding are of high importance to the application of graphene‐based materials for explosives detection.
Gas Sensing Ability of a Nanostructured Conducting Polypyrrole Film Prepared by Catalytic Electropolymerization on Cu/Au Interdigital Electrodes
Authors: Alizadeh Naader , Babaei Mohsen , Nabavi Samaneh
Published: August 2013

Nanostructured conductive polypyrrole has been prepared electrochemically on the surfaces of Cu/Au interdigital electrodes in the presence of Fe(II) as catalyst and ClO4− as anion dopant by using constant potential amperometry and cyclic voltammetry. The morphology of the conducting films was examined by field emission scanning electron microscopy, indicating a dependence from the processing technique. The synthesized polymer was used to investigate the properties of the gas sensing ability. The effect of the catalyst concentration on the oxidation mechanism of pyrrole was discussed. The PPy‐ClO4 gas sensors had demonstrated fast response time and high sensitivity to VOCs.
Preparation of Silver Nanoparticles‐Based Sensors for the Electrochemical Detection of Thiourea in Leaching Solutions of Waste Electrical and Electronic Equipment
Authors: Tashdjian Agustín , Sánchez Loredo María Guadalupe , González Graciela Alicia
Published: August 2013

Waste of electrical and electronic equipment is an interesting secondary resource of base and precious metals. Particularly the use of thiourea‐leaching in acidic medium was proposed for noble metals recovery. In this work, a novel and easy‐to‐use electrochemical sensor was developed, aimed to test thiourea from leaching solutions containing significant thiourea and copper amounts. The sensor was constructed using silver nanoparticles (AgNPs) deposited on screen‐printed electrodes. Its performance was studied in a synthetic leaching solution; changes in the overall surface charge of AgNPs resulting in changes in the charge‐transfer resistance for the copper ions were evaluated by electrochemical impedance spectroscopy.
Electrochemical Magnetic Immunosensors for the Determination of Ceruloplasmin
Authors: Ojeda Irene , Moreno‐Guzmán María , González‐Cortés Araceli , Yáñez‐Sedeño Paloma , Pingarrón José M.
Published: August 2013

Electrochemical immunosensors for ceruloplasmin (Cp) are reported for the first time. Two configurations involving magnetic beads (MBs) functionalized with Protein A or Streptavidin for immobilization of Cp antibodies were compared, using competitive immunoassay with synthesized alkaline phosphatase‐Cp conjugate. Upon capturing MBs‐immunoconjugates onto screen‐printed carbon electrodes, quantification of Cp was accomplished by DPV measurement of 1‐naphthol generated after 1‐naphthylphosphate addition. Linear ranges of calibration curves and detection limits were 0.1–1000 µg/mL and 0.040 µg/mL (Protein A‐MBs), and 0.025–20 µg/mL and 0.018 µg/mL (Strept‐MBs). Good results were obtained in the determination of Cp in spiked human serum samples.
Ecogenetics of mercury: From genetic polymorphisms and epigenetics to risk assessment and decision-making
Authors: Basu Niladri , Goodrich Jaclyn M. , Head Jessica
Published: August 2013

The risk assessment of mercury (Hg), in both humans and wildlife, is made challenging by great variability in exposure and health effects. Although disease risk arises following complex interactions between genetic (“nature”) and environmental (“nurture”) factors, most Hg studies thus far have focused solely on environmental factors. In recent years, ecogenetic-based studies have emerged and have started to document genetic and epigenetic factors that may indeed influence the toxicokinetics or toxicodynamics of Hg. The present study reviews these studies and discusses their utility in terms of Hg risk assessment, management, and policy and offers perspectives on fruitful areas for future research. In brief, epidemiological studies on populations exposed to inorganic Hg (e.g., dentists and miners) or methylmercury (e.g., fish consumers) are showing that polymorphisms in a number of environmentally responsive genes can explain variations in Hg biomarker values and health outcomes. Studies on mammals (wildlife, humans, rodents) are showing Hg exposures to be related to epigenetic marks such as DNA methylation. Such findings are beginning to increase understanding of the mechanisms of action of Hg, and in doing so they may help identify candidate biomarkers and pinpoint susceptible groups or life stages. Furthermore, they may help refine uncertainty factors and thus lead to more accurate risk assessments and improved decision-making. Environ Toxicol Chem 2014;33:1248–1258. © 2013 SETAC
A fictitious domain approach for the Stokes problem based on the extended finite element method
Authors: Court Sébastien , Fournié Michel , Lozinski Alexei
Published: August 2013

In the present work, we propose to extend to the Stokes problem a fictitious domain approach inspired by extended finite element method and studied for the Poisson problem in a paper of Renard and Haslinger of 2009. The method allows computations in domains whose boundaries do not match. A mixed FEM is used for the fluid flow. The interface between the fluid and the structure is localized by a level‐set function. Dirichlet boundary conditions are taken into account using Lagrange multiplier. A stabilization term is introduced to improve the approximation of the normal trace of the Cauchy stress tensor at the interface and avoid the inf‐sup condition between the spaces for the velocity and the Lagrange multiplier. Convergence analysis is given, and several numerical tests are performed to illustrate the capabilities of the method. Copyright © 2013 John Wiley & Sons, Ltd.
Are we missing the tail (and the tale) of residence time distributions in watersheds?
Authors: Frisbee Marty D. , Wilson John L. , Gomez‐Velez Jesus D. , Phillips Fred M. , Campbell Andrew R.
Published: August 2013

Residence times provide vital information on hydrological, geochemical, and ecological processes in watersheds. The common perception is that mean residence times in watersheds are very short, on the order of days to years. However, there is growing concern that longer residence times of centuries to millennia are not being captured by traditional surface water age‐dating methods. We hypothesize that if mean residence times are biased short, then weathering rates calculated from mean residence times will be forced unrealistically high to match observed solute concentrations. We test this hypothesis by calculating weathering rates from springs based upon residence times estimated using three different age‐dating methods. Observed solute concentrations require unrealistically large weathering rates if typical short residence times are employed as compared to rates derived from longer residence times. Residence time distributions in watersheds have substantially longer tails than previously thought, with implications for age‐dating methods and their interpretation to infer process behavior.
Charred forests increase snowmelt: Effects of burned woody debris and incoming solar radiation on snow ablation
Authors: Gleason Kelly E. , Nolin Anne W. , Roth Travis R.
Published: August 2013

We document effects of postfire forest conditions on snow accumulation, albedo, and ablation in the Oregon Cascades. We measured snow water equivalent, solar radiation, snow albedo, and snowpack surface debris at a pair of burned and unburned forest plots. Snow accumulation was greater in the burned forest; however, the snowpack disappeared 23 days earlier and had twice the ablation rate than in the unburned forest. Snow albedo was 40% lower in the burned forest during ablation, while approximately 60% more solar radiation reached the snow surface, driving a 200% increase in net shortwave radiation. Significant amounts of pyrogenic carbon particles and larger burned woody debris shed from standing charred trees accumulated on the snowpack and darkened its surface. Spatial analysis showed that across the Western U.S., 80% of all forest fires occurred in the seasonal snow zone, and were 4.4 times larger than fires outside the seasonal snow zone.
Field‐aligned currents associated with dipolarization fronts
Authors: Sun W. J. , Fu S. Y. , Parks G. K. , Liu J. , Yao Z. H. , Shi Q. Q. , Zong Q.‐G. , Huang S. Y. , Pu Z. Y. , Xiao T.
Published: August 2013

Current densities associated with dipolarization fronts (DFs) have been calculated in the geomagnetic tail using the curlometer technique applied to high‐resolution magnetic field data obtained by the four Cluster spacecraft. We then use the relation to characterize the behavior of field‐aligned current (FAC) during 25 DF events. Our results show that the magnitude of FAC density (J//) ranges from 5 to 20 nA/m2, and they are observed in Northern and Southern Hemispheres flowing along both directions of the ‐field. The FACs have dimensions characteristic of the DFs and with region‐1 current sense flowing inside the DFs and region‐2 sense just in front of DF (in the Bz dips). Most of our observations come from 15 to 20 RE in the tail, different from previous statistical studies based mainly on observations made around 9–12 RE. We suggest that DFs can sustain significant FACs and appear as “wedgelets” in the early stage.
Visible channel development during the initial breakdown of a natural negative cloud‐to‐ground flash
Authors: Campos Leandro Z. S. , Saba Marcelo M. F.
Published: August 2013

GPS time synchronized high‐speed video records (at 4000 frames per second) and electric field waveforms are discussed for one stepped leader of a negative cloud‐to‐ground flash whose initial development becomes visible above cloud base. The leader emerges from the opaque region of the thundercloud around 4800 m above ground, propagating with speeds of the order of 106 m s−1. It is possible to see that this early, bright, and fast propagation period occurred simultaneously with the emission of initial breakdown bipolar pulse trains. The leader gradually reduces its speed and luminous intensity: When its tip is less than 3000 m above the ground, the propagation speeds oscillate between 2 and 4 × 105 m s−1 until it makes contact approximately 16 ms after it first became visible. With time, the initial breakdown waveform is gradually replaced by unipolar pulses and the leader propagation speed drops to the 105 m s−1 range.
Distinguishing between pain intensity and pain resolution: Using acute post‐surgical pain trajectories to predict chronic post‐surgical pain
Authors: Althaus A. , Arránz Becker O. , Neugebauer E.
Published: August 2013

Background

High intensity of acute post‐surgical pain is one of the strongest predictors for chronic post‐surgical pain (CPSP). We investigated the predictive power of acute post‐surgical pain trajectories and the interplay of pain trajectories and diverse psychosocial risk factors in the development of CPSP.

Methods

Data from 199 patients were examined using latent growth curve analysis by means of structural equation modelling. This analytical approach was used to explicitly test the mediating role of acute pain trajectories within the association between preoperative psychosocial vulnerability factors and CPSP.

Results

Both initial pain intensity and pain resolution during the first five post‐operative days independently contributed to the prediction of CPSP 6 months after surgery. In terms of vulnerability, anxiety and depression had clear but opposing effects on post‐operative pain trajectories. Whereas depressive patients exhibited impaired pain resolution, patients with high anxiety showed better rates of pain resolution after surgery. Both effects on acute pain resolution extended to chronic pain 6 months after surgery.

Conclusions

In this study, we demonstrated that going beyond conventional one‐time measurements of acute pain by modelling pain trajectories may substantially enhance research on pain chronification in two ways: First, pain trajectories bear great potential to improve the prediction of CPSP. Second, they represent a meaningful link between psychosocial vulnerability and CPSP because they can be used to uncover mechanisms by which psychosocial vulnerability unfolds. The reported findings suggest that the incidence of CPSP may be reduced by optimizing post‐operative pain monitoring.
Identification of the Vitamin D Receptor in Osteoblasts and Chondrocytes But Not Osteoclasts in Mouse Bone
Authors: Wang Yongji , Zhu Jinge , DeLuca Hector F
Published: August 2013

Bone is clearly a target of vitamin D and as expected, the vitamin D receptor (VDR) is expressed in osteoblasts. However, the presence of VDR in other cells such as osteocytes, osteoclasts, chondroclasts, and chondrocytes is uncertain. Because of difficulties in obtaining sections of undecalcified adult bone, identification of the site of VDR expression in adult bone tissue has been problematic. In addition, the antibodies to VDR used in previous studies lacked specificity, a property crucial for unambiguous conclusions. In the present study, VDR in the various cells from neonatal and adult mouse bone tissues was identified by a highly specific and sensitive immunohistochemistry method following bone decalcification with EGTA. For accurate evaluation of weak immunosignals, samples from Demay VDR knockout mice were used as negative control. Molecular markers were used to identify cell types. Our results showed that EGTA-decalcification of bone tissue had no detectable effect on the immunoreactivity of VDR. VDR was found in osteoblasts and hypertrophic chondrocytes but not in the multinucleated osteoclasts, chondroclasts, and bone marrow stromal cells. Of interest is the finding that immature osteoblasts contain large amounts of VDR, whereas the levels are low or undetectable in mature osteoblasts including bone lining cells and osteocytes. Proliferating chondrocytes appear devoid of VDR, although low levels were found in the hypertrophic chondrocytes. These data demonstrate that osteoblasts and chondrocytes are major targets of 1α,25-dihydroxyvitamin D, but osteoclasts and chondroclasts are minor targets or not at all. A high level of VDR was found in the immature osteoblasts located in the cancellous bone, indicating that they are major targets of 1α,25-dihydroxyvitamin D. Thus, the immature osteoblasts are perhaps responsible for the vitamin D hormone signaling resulting in calcium mobilization and in osteogenesis. © 2014 American Society for Bone and Mineral Research.
Electron density deformations provide new insights into the spectral shift of rhodopsins
Authors: Hernández‐Rodríguez Erix Wiliam , Montero‐Alejo Ana Lilian , López Rafael , Sánchez‐García Elsa , Montero‐Cabrera Luis Alberto , García de la Vega José Manuel
Published: August 2013

Spectral shifts of rhodopsin, which are related to variations of the electron distribution in 11‐cis‐retinal, are investigated here using the method of deformed atoms in molecules. We found that systems carrying the M207R and S186W mutations display large perturbations of the π‐conjugated system with respect to wild‐type rhodopsins. These changes agree with the predicted behavior of the bond length alternation (BLA) and the blue shifts of vertical excitation energies of these systems. The effect of the planarity of the central and Schiff‐base regions of retinal chain on the electronic structure of the chromophore is also investigated. By establishing nonlinear polynomial relations between BLA, chain distortions, and vertical excitation energies, we are also able to provide a semiquantitative approach for the understanding of the mechanisms regulating spectral shifts in rhodopsin and its mutants. © 2013 Wiley Periodicals, Inc.
15‐LO/15‐HETE Mediated Vascular Adventitia Fibrosis via p38 MAPK‐Dependent TGF‐β
Authors: Zhang Li , Li Yumei , Chen Minggang , Su Xiaojie , Yi Dan , Lu Ping , Zhu Daling
Published: August 2013

15‐Lipoxygenase/15‐hydroxyeicosatetraenoic acid (15‐LO/15‐HETE) is known to modulate pulmonary vascular medial hypertrophy and intimal endothelial cells migration and angiogenesis after hypoxia. However, it is unclear whether 15‐HETE affects the adventitia of the pulmonary arterial wall. We performed immunohistochemistry, adventitia fibrosis, pulmonary artery fibroblasts phenotype and extracellular matrix (ECM) deposition to determine the role of 15‐HETE in hypoxia‐induced pulmonary vascular adventitia remodeling. Our studies showed that O2 deprivation induced adventitia hypertrophy of pulmonary arteries with ECM accumulation in both humans with pulmonary arterial hypertension and hypoxic rats. Hypoxia induced 15‐LO expression in adventitia. With the inhibitor, NDGA depressed the hypoxia induced ECM deposition and 15‐LO production in hypoxic rats. Hypoxia up‐regulated the expression of α‐SMA, type‐Ia collagen and fibronectin in cultured fibroblasts, which seemed to be due to the increased 15‐LO/15‐HETE. Exogenous 15‐HETE mediated the ECM and phenotypic alterations of the fibroblasts as well. The 15‐LO/15‐HETE induced adventitia fibrosis and fibroblasts phenotypic alterations depended on signaling of the transforming growth factor‐β1 (TGF‐β1)/Smad2/3 pathway. P38 mitogen‐activated protein kinase (p38 MAPKs) was likely to mediate 15‐LO induced TGF‐β1 and Smad2/3 activation after hypoxia. The results suggest that adventitia fibrosis is an important event in the hypoxia induced pulmonary arterial remodeling, which relies on 15‐LO/15‐HETE induced p38 MAPK‐dependent TGF‐β1/Smad2/3 intracellular signaling systems. J. Cell. Physiol. 229: 245–257, 2014. © 2013 Wiley Periodicals, Inc.
Sonographic appearance of the cavum septum pellucidum et vergae in normal fetuses in the second and third trimesters of pregnancy
Authors: Tao Guowei , Lu Gang , Zhan Xinfeng , Li Jun , Cheng Lin , Lee Kingyin , Poon Wai Sang
Published: August 2013

Background

To characterize the cavum septum pellucidum et vergae (CSPV) in normal fetuses in the second to third trimester.

Methods

The cavum septum pellucidum (CSP) and CSPV were investigated in 322 uncomplicated singleton pregnancies from 25 to 39 weeks' gestation. Visualization rate, width, and morphology of both CSP and cavum vergae (CV) were assessed by ultrasound and MRI.

Results

The CSP and CSPV visualization rates were 100% and 7.8% (25/322), respectively. The mean widths were 6.3 ± 1.2 mm (3.4–10 mm) and 6.7 ± 1.0 mm (5.1–9 mm), respectively, with no significant correlation between width and gestational age (r = −0.108, p > 0.05 and r = −0.182, p > 0.05, respectively). In CSPV fetuses, the CV to CSP ratio was 1.004 ± 0.018 (0.967–1.033). All CSPVs were rectangular in the transverse plane and extended posteriorly beyond the midpoint of the brain.

Conclusions

Common features of CSPVs include (1) a rectangular morphology, (2) communication between the two cavities, (3) a CV width within the normal range for CSP, and (4) a CV‐CSP ratio of 1. These findings may help distinguish normal from abnormal CSPV. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 41:525–531, 2013.
Glutathione‐sensitive RGD‐poly(ethylene glycol)‐SS‐polyethylenimine for intracranial glioblastoma targeted gene delivery
Authors: Lei Yang , Wang Jing , Xie Cao , Wagner Ernst , Lu Weiyue , Li Ying , Wei Xiaoli , Dong Jibin , Liu Min
Published: August 2013

Background

Reductively reversible and hydrolytically degradable cationic polymers have been used as gene delivery systems. The present study aimed to enhance the low transfection efficiency caused by PEGylation by taking advantage of a nonviral vector containing a disulfide linkage.

Methods

The novel reducible targeted gene vector c(RGDyK)‐poly(ethylene glycol)‐SS‐polyethylenimine (RGD‐PEG‐SS‐PEI), representing a combination of RGD‐PEG with PEI through a disulfide linkage, was synthesized and its reduction‐sensitivity was tested in the presence of glutathione. The RGD‐PEG‐SS‐PEI/pDNA complexes were formed and their stability was evaluated by agarose gel electrophoresis in both phosphate‐buffered saline and Dulbecco's modified Eagle's medium with 10% serum. In vitro transfection efficiency and cell viability assay of the different polymers was performed for U87 cells using pEGFP‐N2 and pGL4.2 reporter gene systems. RGD‐PEG‐SS‐PEI/pDsRED‐N1 and RGD‐PEG‐PEI/pDsRED‐N1 complexes were injected intravenously into the U87 cell‐bearing nude mice via their tail vein to investigate in vivo gene expression.

Results

RGD‐PEG‐SS‐PEI has been synthesized successfully and its reduction‐sensitivity was confirmed in the presence of glutathione. The RGD‐PEG‐SS‐PEI/pDNA complexes demonstrated good stability in both conditions. In comparison with mPEG‐PEI/pDNA for gene delivery, the RGD‐PEG‐SS‐PEI/pDNA complex provided improved levels of transfection efficiency and reduced cytotoxicity when tested in U87 cells in vitro, and also enhanced levels of gene expression in the brains of intracranial U87 glioblastoma‐bearing mice as demonstrated using dsRed gene transfer and bioimaging in vivo.

Conclusions

The results of the present study suggest that RGD‐PEG‐SS‐PEI represents a promising candidate for further study in glioblastoma and combined gene therapies. Copyright © 2013 John Wiley & Sons, Ltd.
A kinetic model for the methane hydrate precipitated from venting gas at cold seep sites at Hydrate Ridge, Cascadia margin, Oregon
Authors: Cao Yuncheng , Chen Duofu , Cathles Lawrence M.
Published: August 2013

We develop a kinetic model for hydrate crystallization from methane gas venting through shallow sediments at Hydrate Ridge on the Cascadia margin of Oregon that predicts how pore water chlorinity, temperature, and crystallized hydrate evolve after the onset of steady venting. Predictions are compared to observations at Ocean Drilling Program Site 1249. In the preferred model, calculated gas hydrate saturation and chloride concentrations reach those observed at depths less than 20 m below seafloor (bsf) under the southern summit of Hydrate Ridge in ~650 years, and the vertical water flux must be less than 50 kg/m2/yr. Hydrate accumulates more slowly between 20 m bsf and the base of the hydrate stability zone where there is no free gas, accumulating to observed levels of a few volume percent of hydrate in 105 to 106 years, depending on the water flux that is assumed through this zone. This dichotomy means that the presently observed gas venting must have been diverted to this area ~650 years ago, or be episodic and infrequent. If the gas venting for the last 650 years has been as observed today, the latent heat of hydrate precipitation in the upper 20 m of sediments would have caused the temperature to increase ~0.8°C at ~20 m bsf and ~0.2°C at ~100 m bsf. This would have caused a ~5 m rise in the elevation of the base of hydrate stability zone, and decreased the rate of hydrate crystallization from 1.5 kg CH4/m2/yr 650 years ago to 0.7 kg CH4/m2/yr today.
Rain characteristics and large‐scale environments of precipitation objects with extreme rain volumes from TRMM observations
Authors: Zhou Yaping , Lau William K. M. , Liu Chuntao
Published: August 2013

This study adopts a “precipitation object” approach by using 14 years of Tropical Rainfall Measuring Mission (TRMM) Precipitation Feature (PF) and National Centers for Environmental Prediction (NCEP) reanalysis data to study rainfall structure and environmental factors associated with extreme heavy rain events. Characteristics of instantaneous extreme volumetric PFs are examined and compared to those of intermediate and small systems. It is found that instantaneous PFs exhibit a much wider scale range compared to the daily gridded precipitation accumulation range. The top 1% of the rainiest PFs contribute over 55% of total rainfall and have 2 orders of rain volume magnitude greater than those of the median PFs. We find a threshold near the top 10% beyond which the PFs grow exponentially into larger, deeper, and colder rain systems. NCEP reanalyses show that midlevel relative humidity and total precipitable water increase steadily with increasingly larger PFs, along with a rapid increase of 500 hPa upward vertical velocity beyond the top 10%. This provides the necessary moisture convergence to amplify and sustain the extreme events. The rapid increase in vertical motion is associated with the release of convective available potential energy (CAPE) in mature systems, as is evident in the increase in CAPE of PFs up to 10% and the subsequent dropoff. The study illustrates distinct stages in the development of an extreme rainfall event including (1) a systematic buildup in large‐scale temperature and moisture, (2) a rapid change in rain structure, (3) explosive growth of the PF size, and (4) a release of CAPE before the demise of the event.
Synthesis and In Vitro Antibacterial Activities of Novel 2‐Aryl‐3‐(phenylamino)‐2,3‐dihydroquinazolin‐4(1H)‐one Derivatives
Authors: Mohammadi Ali A. , Rohi Hamed , Soorki Ali Abolhasani
Published: August 2013

An efficient synthesis of novel 2‐aryl‐3‐(phenylamino)‐2,3‐dihydroquinazolin‐4(1H)‐one derivatives using KAl(SO4)2.12H2O (Alum) as a catalyst from an aldehyde and 2‐amino‐N‐phenylbenzohydrazine in ethanol is described. All synthesized derivatives were screened for anti‐bacterial activity. Some compounds exhibited promising anti‐bacterial activity with reference to standard antibiotics.
An Efficient Synthetic Protocol for Quinoxalinones, Benzoxazinones, and Benzothiazinones from 2‐Oxo‐2‐aryl‐acetyl Bromide Precursors
Authors: Nagaraj Muthupandi , Sathiyamoorthy Sithuraj , Boominathan Muthusamy , Muthusubramanian Shanmugam , Bhuvanesh Nattamai
Published: August 2013

α‐Bromoketones undergo selenium dioxide oxidation to yield reactive 2‐oxo‐2‐arylacetyl bromides that are trapped by aryl‐1,2‐diamines, 1,2‐aminophenol or 1,2‐aminothiophenol to give quinoxalinones, benzoxazinones, and benzothiazinones, respectively, in good yield.
An Efficient and Green Synthesis of 6‐Amino‐3‐phenyl‐4‐aryl‐1,4‐dihydropyrano [2,3‐c]pyrazole‐5‐carbonitrile Derivatives under Ultrasound Irradiation in Aqueous Medium
Authors: Zou Yi , Hu Yu , Liu Hai , Shi Da‐Qing
Published: August 2013

A facile and eco‐friendly approach for the synthesis of 6‐amino‐3‐phenyl‐4‐aryl‐1,4‐dihydropyrano[2,3‐c]pyrazole‐5‐carbonitrile derivatives via four‐component reaction of hydrazine, ethyl 3‐oxo‐3‐phenylpropanoate, aldehydes, and malononitrile is described. The reaction is performed in water, without using any catalyst, and under ultrasound irradiation. The developed sonochemical‐assisted multi‐component reaction provides an improved and accelerated conversion when compared with conventional procedure.
Human pharmacokinetics of xanthohumol, an antihyperglycemic flavonoid from hops
Authors: Legette LeeCole , Karnpracha Chanida , Reed Ralph L. , Choi Jaewoo , Bobe Gerd , Christensen J. Mark , Rodriguez‐Proteau Rosita , Purnell Jonathan Q. , Stevens Jan F.
Published: August 2013

Scope

Xanthohumol (XN) is a bioactive prenylflavonoid from hops. A single‐dose pharmacokinetic (PK) study was conducted in men (n = 24) and women (n = 24) to determine dose–concentration relationships.

Methods and results

Subjects received a single oral dose of 20, 60, or 180 mg XN. Blood was collected at 0, 0.25, 0.5, 1, 2, 4, 8, 12, 24, 48, 72, 96, and 120 h. Plasma levels of XN and its metabolites, isoxanthohumol (IX), 8‐prenylnaringenin (8PN), and 6‐prenylnaringenin (6PN) were measured by LC‐MS/MS. Xanthohumol (XN) and IX conjugates were dominant circulating flavonoids among all subjects. Levels of 8PN and 6PN were undetectable in most subjects. The XN PK profile showed peak concentrations around 1 h and between 4–5 h after ingestion. The maximum XN concentrations (Cmax) were 33 ± 7 mg/L, 48 ± 11 mg/L, and 120 ± 24 mg/L for the 20, 60, and 180 mg dose, respectively. Using noncompartmental modeling, the area under the curves (AUC0→∞) for XN were 92 ± 68 h × μg/L, 323 ± 160 h × μg/L, and 863 ± 388 h × μg/L for the 20, 60, and 180 mg dose, respectively. The mean half‐life of XN was 20 h for the 60 and 18 h for the 180 mg dose.

Conclusion

XN has a distinct biphasic absorption pattern with XN and IX conjugates being the major circulating metabolites.
Contrasting echogenicity in flexor digitorum profundus–flexor carpi ulnaris: A diagnostic ultrasound pattern in sporadic inclusion body myositis
Authors: Noto Yu‐Ichi , Shiga Kensuke , Tsuji Yukiko , Kondo Masaki , Tokuda Takahiko , Mizuno Toshiki , Nakagawa Masanori
Published: August 2013

Introduction: In this study we aimed to clarify whether muscle ultrasound (US) of the forearm can be used to differentiate between patients with sporadic inclusion body myositis (s‐IBM) and those with s‐IBM–mimicking diseases. Methods: We compared the echo intensity (EI) of the flexor digitorum profundus (FDP) muscle and the flexor carpi ulnaris (FCU) muscles in patients with s‐IBM (n = 6), polymyositis/dermatomyositis (PM/DM; n = 6), and amyotrophic lateral sclerosis (ALS; n = 6). Results: We identified EI abnormalities in 100% of patients with s‐IBM, 33% of those with PM/DM, and 33% of those with ALS. An “FDP–FCU echogenicity contrast,” a US pattern involving a higher EI in the FDP than in the FCU, was observed in all patients with s‐IBM, but in none of those with PM/DM or ALS. Conclusions: FDP–FCU echogenicity contrast in muscle US is a sensitive diagnostic indicator of s‐IBM. Muscle Nerve 49: 745–748, 2014