bluuebunny/crossref_metadata_2025 huggingface dataset:
Low frequency electromagnetic radiation from sprite streamers
Authors: Qin Jianqi , Celestin Sebastien , Pasko Victor P.
Published: October 2012

Sprites are mesospheric discharges that carry significant electrical currents and produce electromagnetic radiation observed typically in the extremely low (ELF) to ultra low (ULF) frequency bands. In this letter, we present the first theoretical estimates of the electromagnetic radiation produced by individual sprite streamers using simulation results from a plasma fluid model. It is demonstrated that the spectral content of the radiation produced by sprite streamers is a function of the air density Nand the lightning‐induced quasi‐static ambient electric fieldE in the regions of space where the sprite streamers are propagating. We demonstrate that the exponential growth of the current in sprite streamers at 75 km would be preferentially associated with electromagnetic radiation in the frequency range from 0 and up to ∼3 kHz, whereas the growth of the streamer current at 40 km could produce radiation with frequencies up to ∼300 kHz, consistently with the scaling of atmospheric air density. We further conjecture that the periodic branching of streamers may lead to a radiation spectrum enhancement in the very low (VLF) to low frequency (LF) range.
Chorus, ECH, and Z mode emissions observed at Jupiter and Saturn and possible electron acceleration
Authors: Menietti J. D. , Shprits Y. Y. , Horne R. B. , Woodfield E. E. , Hospodarsky G. B. , Gurnett D. A.
Published: October 2012

In this paper we compare and contrast chorus, electron cyclotron harmonics (ECH), and Z mode emissions observed at Jupiter and Saturn and relate them to recent work on electron acceleration at Earth. Intense chorus emissions are observed near the magnetic equator, the likely source region, but the strongest intensities are on either side of the magnetic equator. Chorus intensities at Jupiter are generally about an order of magnitude larger than at Saturn, and the bandwidth of chorus at Jupiter can reach 7 or 8 kHz (∼0.6 fc), while at Saturn it is typically <2 kHz (∼0.6 fc, also). No higher‐latitude information is available at Jupiter; however, high inclination orbits at Saturn by Cassini reveal strong chorus intensities at latitudes extending to over 30°. At Jupiter, initial studies reveal the chorus intensities are sufficient to accelerate electrons by a stochastic process; however, the high density levels near the source region of chorus at Saturn indicate a less efficient process except for local regions such as within plasma injection regions. The role of Z mode in electron acceleration and the role of ECH waves in pitch angle scattering at both Jupiter and Saturn require further study.
Validation of Mode‐S Meteorological Routine Air Report aircraft observations
Authors: Strajnar B.
Published: October 2012

The success of mesoscale data assimilation depends on the availability of three‐dimensional observations with high spatial and temporal resolution. This paper describes an example of such observations, available through Mode‐S air traffic control system composed of ground radar and transponders on board the aircraft. The meteorological information is provided by interrogation of a dedicated meteorological data register, called Meteorological Routine Air Report (MRAR). MRAR provides direct measurements of temperature and wind, but is only returned by a small fraction of aircraft. The quality of Mode‐S MRAR data, collected at the Ljubljana Airport, Slovenia, is assessed by its comparison with AMDAR and high‐resolution radiosonde data sets, which enable high‐ and low‐level validation, respectively. The need for temporal smoothing of raw Mode‐S MRAR data is also studied. The standard deviation of differences between smoothed Mode‐S MRAR and AMDAR is 0.35°C for temperature, 0.8 m/s for wind speed and below 10 degrees for wind direction. The differences with respect to radiosondes are larger, with standard deviations of approximately 1.7°C, 3 m/s and 25 degrees for temperature, wind speed and wind direction, respectively. It is concluded that both wind and temperature observations from Mode‐S MRAR are accurate and therefore potentially very useful for data assimilation in numerical weather prediction models.
Tetramerization of ZapA is required for FtsZ bundling
Authors: Pacheco-Gómez Raúl , Cheng Xi , Hicks Matthew R. , Smith Corinne J. I. , Roper David I. , Addinall Stephen , Rodger Alison , Dafforn Timothy R.
Published: October 2012

Prokaryotic cell division is a highly orchestrated process requiring the formation of a wide range of biomolecular complexes, perhaps the most important of these involving the prokaryotic tubulin homologue FtsZ, a fibre-forming GTPase. FtsZ assembles into a ring (the Z-ring) on the inner surface of the inner membrane at the site of cell division. The Z-ring then acts as a recruitment site for at least ten other proteins which form the division apparatus. One of these proteins, ZapA, acts to enhance lateral associations between FtsZ fibres to form bundles. Previously we have expressed, purified and crystallized ZapA and demonstrated that it exists as a tetramer. We also showed that ZapA binds to FtsZ polymers, strongly promoting their bundling, while inhibiting FtsZ GTPase activity by inducing conformational changes in the bound nucleotide. In the present study we investigate the importance of the tetramerization of ZapA on its function. We generated a number of mutant forms of ZapA with the aim of disrupting the dimer–dimer interface. We show that one of these mutants, I83E, is fully folded and binds to FtsZ, but is a constitutive dimer. Using this mutant we show that tetramerization is a requirement for both FtsZ bundling and GTPase modulation activities.
Direct observation of grain growth from molten silicon formed by micro-thermal-plasma-jet irradiation
Authors: Hayashi Shohei , Fujita Yuji , Kamikura Takahiro , Sakaike Kohei , Akazawa Muneki , Ikeda Mitsuhisa , Hanafusa Hiroaki , Higashi Seiichiro
Published: October 2012

Phase transformation of amorphous-silicon during millisecond annealing using micro-thermal-plasma-jet irradiation was directly observed using a high-speed camera with microsecond time resolution. An oval-shaped molten-silicon region adjacent to the solid phase crystallization region was clearly observed, followed by lateral large grain growth perpendicular to a liquid-solid interface. Furthermore, leading wave crystallization (LWC), which showed intermittent explosive crystallization, was discovered in front of the moving molten region. The growth mechanism of LWC has been investigated on the basis of numerical simulation implementing explosive movement of a thin liquid layer driven by released latent heat diffusion in a lateral direction.
Naturally asymmetrical double-Schottky barrier model: Based on observation of bicrystal
Authors: Cheng Chenlu , He Jinliang , Hu Jun
Published: October 2012

ZnO bicrystals with specific coincidence site lattice twist boundaries are manufactured for investigation. Asymmetrical I-V behaviors occur with maximum nonlinear coefficient of forward direction tenfold of reverse one. Energy dispersion spectra measurement reveals the nonuniform distributions of elements such as bismuth and oxygen in the grain boundary region. This reflects a higher Schottky barrier formed at Zn-polar face than that at O-polar face, which is confirmed by capacitance-voltage method. Such natural asymmetry may result from the effect of spontaneous polarization of polar surfaces of ZnO. Finally, simulation results prove the validity of the asymmetrical model proposed.
Description of the gastrointestinal tract and associated organs of the kultarr (Antechinomys laniger)
Authors: Stannard Hayley J. , Old Julie M.
Published: October 2012

This paper provides a macro- and microscopic description of the digestive tract of the kultarr (Antechinomys laniger), a small dasyurid marsupial. The digestive tract was simple, with no external differentiation between the small and large intestine, and lacked a caecum. Mean gross length of the kultarr digestive tract was 165.2 ± 32.1 mm. Microscopically, the tissues had cell types similar to those of other mammals. The new information will aid future post-mortem investigations of captive kultarrs and future studies of nutrition.
Age-related change in spurs and spur sheaths of the platypus (Ornithorhynchus anatinus)
Authors: Williams G. A. , Serena M. , Grant T. R.
Published: October 2012

Non-invasive techniques for age assessment of wild mammals are needed for effective species management as well as research. In the case of the platypus, we investigated how morphology of calcaneal spurs and associated features in males and vestigial spur sheaths in females varies with age. Total spur length in males (spur tip to base of subtending epidermal collar) is greatest at 19–24 months and falls thereafter, with significant linear relationships evident between spur length and age of subadults (13–24 months old) and adults (≥25 months old). However, collar length/total spur length discriminates better between subadults and older animals than either collar length or total spur length alone. Juveniles can be reliably identified up to the age of 12 months (males) and 9 months (females) by the presence, respectively, of a sheath encasing the spur or a rudimentary spur sheath. A small proportion of young subadults (males, 4%; females, ≤2%) will be misclassified as juveniles due to sheaths being retained for longer than normal. Studies that need to identify juveniles very accurately as an age class should avoid sampling populations from August–October on the south-eastern Australian mainland (or May–October if subadult males also need to be identified correctly).
Cautionary considerations for positive dingo management: a response to the Johnson and Ritchie critique of Fleming et al. (2012)
Authors: Fleming Peter J. S. , Allen Benjamin L. , Ballard Guy-Anthony
Published: October 2012

Johnson and Ritchie (2012) have provided a criticism of our opinion piece (Fleming et al. 2012). There is some common ground, but we remain unconvinced by their view that our reasoning was unsound or beside the point. In this response, we discuss where Johnson and Ritchie have provided unconvincing evidence to refute our seven considerations, and reiterate and demonstrate why these considerations remain important. The mesopredator release or suppression hypothesis in Australian ecosystems must be objectively evaluated before positive management of dingoes and other free-ranging dogs is recommended or implemented. Adaptive comanagement of free-ranging dogs can be used for both biodiversity conservation and the mitigation of livestock predation but caution must be exercised when considering using free-ranging dogs as a conservation tool.
Anthrax toxin protective antigen integrates poly-γ-
d
-glutamate and pH signals to sense the optimal environment for channel formation
Authors: Kintzer Alexander F. , Tang Iok I , Schawel Adam K. , Brown Michael J. , Krantz Bryan A.
Published: October 2012

Many toxins assemble into oligomers on the surface of cells. Local chemical cues signal and trigger critical rearrangements of the oligomer, inducing the formation of a membrane-fused or channel state.
Bacillus anthracis
secretes two virulence factors: a tripartite toxin and a poly-γ-
d
-glutamic acid capsule (γ-DPGA). The toxin’s channel-forming component, protective antigen (PA), oligomerizes to create a prechannel that forms toxic complexes upon binding the two other enzyme components, lethal factor (LF) and edema factor (EF). Following endocytosis into host cells, acidic pH signals the prechannel to form the channel state, which translocates LF and EF into the host cytosol. We report γ-DPGA binds to PA, LF, and EF, exhibiting nanomolar avidity for the PA prechannel oligomer. We show PA channel formation requires the pH-dependent disruption of the intra-PA domain-2–domain-4 (D2-D4) interface. γ-DPGA stabilizes the D2-D4 interface, preventing channel formation both in model membranes and cultured mammalian cells. A 1.9-Å resolution X-ray crystal structure of a D2-D4-interface mutant and corresponding functional studies reveal how stability at the intra-PA interface governs channel formation. We also pinpoint the kinetic pH trigger for channel formation to a residue within PA’s membrane-insertion loop at the inter-PA D2-D4 interface. Thus, γ-DPGA may function as a chemical cue, signaling that the local environment is appropriate for toxin assembly but inappropriate for channel formation.
Temperature-dependent terahertz conductivity of tin oxide nanowire films
Authors: Zou Xingquan , Luo Jingshan , Lee Dongwook , Cheng Chuanwei , Springer Daniel , Nair Saritha K , Cheong Siew Ann , Fan Hong Jin , Chia Elbert E M
Published: October 2012

Temperature-dependent terahertz conductivity of tin oxide (SnO2) nanowire films was measured from 10 to 300 K using terahertz time-domain spectroscopy. The optical parameters, including the complex refractive index, optical conductivity and dielectric function, were obtained using a simple effective medium theory. The complex conductivity was fitted with the Drude–Smith model and the plasmon model. The results show that the carrier density (N) and plasmon resonance frequency (ω
0) increase while the scattering time decreases with increasing temperature. The reduced carrier mobility compared with bulk SnO2 indicates the presence of carrier localization or trapping in these nanowires.
Left cardiac sympathetic denervation for treatment of symptomatic systolic heart failure patients: a pilot study
Authors: Conceição‐Souza Germano Emílio , Pêgo‐Fernandes Paulo Manuel , Cruz Fatima das Dores , Guimarães Guilherme Veiga , Bacal Fernando , Vieira Marcelo Luiz Campos , Grupi Cesar José , Giorgi Maria Clementina Pinto , Consolim‐Colombo Fernanda Marciano , Negrão Carlos Eduardo , Rondon Maria Urbana P. , Moreira Luiz Felipe Pinho , Bocchi Edimar Alcides
Published: October 2012

Aims

To evaluate the feasibility, safety, and potential beneficial effects of left cardiac sympathetic denervation (LCSD) in systolic heart failure (HF) patients.

Methods and results

In this prospective, randomized pilot study, inclusion criteria were New York Heart Association (NYHA) functional class II or III, left ventricular ejection fraction (LVEF) ≤40%, sinus rhythm, and resting heart rate >65 b.p.m., despite optimal medical therapy (MT). Fifteen patients were randomly assigned either to MT alone or MT plus LCSD. The primary endpoint was safety, measured by mortality in the first month of follow‐up and morbidity according to pre‐specified criteria. Secondary endpoints were exercise capacity, quality of life, LVEF, muscle sympathetic nerve activity (MSNA), brain natriuretic peptide (BNP) levels and 24 h Holter mean heart rate before and after 6 months. We studied clinical effects in long‐term follow‐up. Ten patients underwent LCSD. There were no adverse events attributable to surgery. In the LCSD group, LVEF improved from 25 ± 6.6 to 33 ± 5.2 (P = 0.03); 6 min walking distance improved from 167 ± 35 to 198 ± 47 m (P = 0.02). Minnesota Living with Heart Failure Questionnaire (MLWHFQ) score physical dimension changed from 21 ± 5 to 15 ± 7 (P = 0.06). The remaining analysed variables were unchanged. During 848 ± 549 days of follow‐up, in the MT group, three patients either died or underwent cardiac transplantation (CT), while in the LCSD group six were alive without CT.

Conclusions

LCSD was feasible and seemed to be safe in systolic HF patients. Its beneficial effects warrant the development of a larger randomized trial.

Trail registration: NCT01224899.
Association between glycated haemoglobin and the risk of congestive heart failure in diabetes mellitus: systematic review and meta‐analysis
Authors: Erqou Sebhat , Lee Chee‐Tin Christine , Suffoletto Matthew , Echouffo‐Tcheugui Justin B. , de Boer Rudolf A. , van Melle Joost P. , Adler Amanda I.
Published: October 2012

Background

Clinical trials to date have not provided definitive evidence regarding the effects of glucose lowering on the incidence of congestive heart failure (CHF). We synthesized available prospective epidemiological data on the association between glycaemia measured by haemoglobin A1c (HbA1c) and incident CHF in individuals with diabetes.

Methods and results

We searched electronic databases and reference lists of selected articles for relevant prospective epidemiological studies. We abstracted data from relevant studies using standardized forms and obtained additional data from investigators when required. We pooled study‐specific relative risk estimates using random‐effects model meta‐analysis.

Of the 1044 citations identified, we included 10 studies comprising 178 929 participants with diabetes and 14 176 incident CHF cases. Five studies included only patients with type 2 diabetes, four studies had predominantly patients with type 2 diabetes, and one study included only patients with type 1 diabetes. All studies except one showed an increased risk of CHF with higher HbA1c. The overall adjusted risk ratio (RR) for CHF was 1.15 [95% confidence interval (CI) 1.10–1.21] for each percentage point higher HbA1c. There was substantial heterogeneity across the 10 studies (I2: 83%; 95% CI 69–91%; P < 0.001) not explained by available study‐level characteristics such as study design or average HbA1c level. In seven studies reporting RRs with more than one degree of adjustment, the association was minimally altered after adjustment for several cardiovascular risk factors.

Conclusions

In observational studies of individuals with diabetes, a higher HbA1c level was associated with a significantly increased incidence of CHF.
Further insights into the underlying electrophysiological mechanisms for reduction of atrial fibrillation by ranolazine in an experimental model of chronic heart failure
Authors: Frommeyer Gerrit , Schmidt Marco , Clauß Catharina , Kaese Sven , Stypmann Jörg , Pott Christian , Eckardt Lars , Milberg Peter
Published: October 2012

Aims

Ranolazine (RAN) was reported to be effective and safe in converting atrial fibrillation (AF) to sinus rhythm by administration of a single dose (‘pill in the pocket’) to patients with structural heart disease. This study examines the underlying mechanisms for the antiarrhythmic benefit of RAN application in chronic heart failure (CHF).

Methods and results

In 10 female rabbits, CHF was induced by rapid ventricular pacing, leading to a significant decrease in ejection fraction in the presence of a dilated left ventricle and atrial enlargement. Twelve rabbits were sham‐operated and served as controls. Isolated hearts were perfused using the Langendorff method. Burst pacing was used to induce AF. Monophasic action potential recordings showed an increase of atrial action potential duration (aAPD) and effective refractory period (aERP) in CHF hearts compared with sham hearts. Infusion of acetylcholine (1 µM) and isoproterenol (1 µM) led to AF in all failing hearts and in 11 sham hearts. Simultaneous infusion of RAN (10 µM) remarkably reduced inducibility of AF in 50% of sham and 50% of failing hearts. RAN had no effect on aAPD but significantly increased aERP, leading to a marked increase in atrial post‐repolarization refractoriness. Moreover, RAN application moderately increased interatrial conduction time.

Conclusion

RAN has been shown to be effective in reducing the inducibility of AF in an experimental model of AF. The antiarrhythmic effect is mainly due to development of atrial post‐repolarization refractoriness and a moderate increase in conduction time. The described electrophysiological mechanisms remain preserved in the setting of CHF.
High-field magnetic white dwarfs as the progeny of early-type stars?
Authors: Dobbie P. D. , Külebi B. , Casewell S. L. , Burleigh M. R. , Parker Q. A. , Baxter R. , Lawrie K. A. , Jordan S. , Koester D.
Published: October 2012

We present an analysis of the newly resolved components of two hot, double-degenerate systems, SDSS J074853.07+302543.5 + J074852.95+302543.4 and SDSS J150813.24+394504.9 + J150813.31+394505.6 (CBS 229). We confirm that each system has widely separated components (a > 100 au) consisting of a H-rich, non-magnetic white dwarf and a H-rich, high-field magnetic white dwarf (HFMWD). The masses of the non-magnetic degenerates are found to be larger than typical of field white dwarfs. We use these components to estimate the total ages of the binaries and demonstrate that both magnetic white dwarfs are the progeny of stars with Minit > 2 M⊙. We briefly discuss the traits of all known hot, wide, magnetic + non-magnetic double degenerates in the context of HFMWD formation theories. These are broadly consistent (chance probability, P ≈ 0.065) with HFMWDs forming primarily from early-type stars and, in the most succinct interpretation, link their magnetism to the fields of their progenitors. Our results do not, however, rule out that HFMWDs can form through close binary interactions and studies of more young, wide double degenerates are required to reach firm conclusions on these formation pathways.
Effect of superfluidity on neutron star oscillations
Authors: Sotani Hajime , Nakazato Ken’ichiro , Iida Kei , Oyamatsu Kazuhiro
Published: October 2012

We consider how superfluidity of dripped neutrons in the crust of a neutron star affects the frequencies of the crust's fundamental torsional oscillations. A non-negligible superfluid part of dripped neutrons, which do not comove with nuclei, acts to reduce the enthalpy density and thus enhance the oscillation frequencies. By assuming that the quasi-periodic oscillations observed in giant flares of soft gamma repeaters arise from the fundamental torsional oscillations and that the mass and radius of the neutron star are in the range 1.4 ≤ M/M⊙ ≤ 1.8 and 10 ≤ R ≤ 14 km, we constrain the density derivative of the symmetry energy as 100 ≲ L ≲ 130 MeV, which is far more severe than the previous one, L ≳ 50 MeV, derived by ignoring the superfluidity.
{5′-O-[Bis(4-methoxyphenyl)(phenyl)methyl]-2′-deoxy-β-D-threopentofuranosyl}thymine ethyl acetate 0.25-solvate
Authors: Zou Pei , Wu Hao , Liu Yaling , Xie Minhao , Wang Hongyong
Published: October 2012

The title compound, C31H32N2O7·0.25C4H8O2, is a key intermediate in the synthesis of [18F]fluorine-labelled thymidine (18F-FLT), which is the most widely used molecular imaging probe for positron emission tomography (PET). The crystallographic asymmetric unit contains two independent thymine molecules plus one partially occupied site for an ethyl acetate molecule. The two independent thymine molecules show similar geometrical features, except that the dimethoxytrityl groups adopt different orientations with respect to the remainder of the molecule. Each thymine base adopts ananticonformation with respect to the attached deoxyribose ring, and the deoxyribose rings show C3-endopuckering. The conformation of the side chain at the C1 position of the deoxyribose ring isgauche+. Intermolecular N—H...O and O—H...O hydrogen bonds link the molecules into one-dimensional chains.
Structure of glycerol-3-phosphate dehydrogenase (GPD1) fromSaccharomyces cerevisiaeat 2.45 Å resolution
Authors: Alarcon David Aparicio , Nandi Munmun , Carpena Xavi , Fita Ignacio , Loewen Peter C.
Published: October 2012

The interconversion of glycerol 3-phosphate and dihydroxyacetone phosphate by glycerol-3-phosphate dehydrogenases provides a link between carbohydrate and lipid metabolism and providesSaccharomyces cerevisiaewith protection against osmotic and anoxic stress. The first structure of a glycerol-3-phosphate dehydrogenase fromS. cerevisiae, GPD1, is reported at 2.45 Å resolution. The asymmetric unit contains two monomers, each of which is organized with N- and C-terminal domains. The N-terminal domain contains a classic Rossmann fold with the (β-α-β-α-β)2motif typical of many NAD+-dependent enzymes, while the C-terminal domain is mainly α-helical. Structural and phylogenetic comparisons reveal four main structure types among the five families of glycerol-3-phosphate and glycerol-1-phosphate dehydrogenases and reveal that theClostridium acetobutylicanprotein with PDB code 3ce9 is a glycerol-1-phosphate dehydrogenase.
Solution structure of the cold-shock-like protein fromRickettsia rickettsii
Authors: Gerarden Kyle P. , Fuchs Andrew M. , Koch Jonathan M. , Mueller Melissa M. , Graupner David R. , O'Rorke Justin T. , Frost Caleb D. , Heinen Heather A. , Lackner Emily R. , Schoeller Scott J. , House Paul G. , Peterson Francis C. , Veldkamp Christopher T.
Published: October 2012

Rocky Mountain spotted fever is caused byRickettsia rickettsiiinfection.R. rickettsiican be transmitted to mammals, including humans, through the bite of an infected hard-bodied tick of the family Ixodidae. Since theR. rickettsiigenome contains only one cold-shock-like protein and given the essential nature of cold-shock proteins in other bacteria, the structure of the cold-shock-like protein fromR. rickettsiiwas investigated. With the exception of a short α-helix found between β-strands 3 and 4, the solution structure of theR. rickettsiicold-shock-like protein has the typical Greek-key five-stranded β-barrel structure found in most cold-shock domains. Additionally, theR. rickettsiicold-shock-like protein, with a ΔGof unfolding of 18.4 kJ mol−1, has a similar stability when compared with other bacterial cold-shock proteins.
Room-temperature X-ray diffraction studies of cisplatin and carboplatin binding to His15 of HEWL after prolonged chemical exposure
Authors: Tanley Simon W. M. , Schreurs Antoine M. M. , Kroon-Batenburg Loes M. J. , Helliwell John R.
Published: October 2012

The anticancer complexes cisplatin and carboplatin are known to bind to both the Nδand the N∊atoms of His15 of hen egg-white lysozyme (HEWL) in the presence of dimethyl sulfoxide (DMSO). However, neither binds in aqueous media after 4 d of crystallization and crystal growth, suggesting that DMSO facilitates cisplatin/carboplatin binding to the N atoms of His15 by an unknown mechanism. Crystals of HEWL cocrystallized with cisplatin in both aqueous and DMSO media, of HEWL cocrystallized with carboplatin in DMSO medium and of HEWL cocrystallized with cisplatin andN-acetylglucosamine (NAG) in DMSO medium were stored for between seven and 15 months. X-ray diffraction studies of these crystals were carried out on a Bruker APEX II home-source diffractometer at room temperature. Room-temperature X-ray diffraction data collection removed the need for cryoprotectants to be used, ruling out any effect that the cryoprotectants might have had on binding to the protein. Both cisplatin and carboplatin still bind to both the Nδand N∊atoms of His15 in DMSO media as expected, but more detail for the cyclobutanedicarboxylate (CBDC) moiety of carboplatin was observed at the N∊binding site. However, two molecules of cisplatin were now observed to be bound to His15 in aqueous conditions. The platinum peak positions were identified using anomalous difference electron-density maps as a cross-check withFo−FcOMIT electron-density maps. The occupancies of each binding site were calculated usingSHELXTL. These results show that over time cisplatin binds to both N atoms of His15 of HEWL in aqueous media, whereas this binding is speeded up in the presence of DMSO. The implication of cisplatin binding to proteins after a prolonged period of time is an important consideration for the length of treatment in patients who are given cisplatin.
Selection of Landmark Points on Nonlinear Manifolds for Spectral Unmixing Using Local Homogeneity
Authors: Chi Junhwa , Crawford Melba
Published: October 2012

Endmember extraction and unmixing methods that exploit nonlinearity in hyperspectral data are receiving increased attention, but they have significant challenges. Global feature extraction methods such as isometric feature mapping have significant computational overhead, which is often addressed for the classification problem via landmark-based methods. Because landmark approaches are approximation methods, experimental results are often highly variable. We propose a new robust landmark selection method for the purpose of pixel unmixing that exploits spectral and spatial homogeneity in a local window kernel. We compare the performance of the method to several landmark selection methods in terms of reconstruction error and processing time.
The effect of emotional distress on persistent pelvic girdle pain after delivery: a longitudinal population study
Authors: Bjelland EK , Stuge B , Engdahl B , Eberhard‐Gran M
Published: October 2012

Objective  To study the prognosis for pelvic girdle pain, and to explore the association between presence of emotional distress during pregnancy and pelvic girdle syndrome 6 months after delivery.

Design  Longitudinal population study.

Setting  Norway, for the period 1999–2008.

Population  A follow‐up of 41 421 women in the Norwegian Mother and Child Cohort who reported pelvic girdle pain at 30 weeks of gestation.

Methods  Data were obtained by self‐administered questionnaires in weeks 17 and 30 of gestation, and 6 months after delivery.

Main outcome measure  Pelvic girdle syndrome 6 months after delivery, defined as pain in the anterior pelvis and on both sides in the posterior pelvis.

Results  Six months after delivery, 78.0% of the women had recovered, 18.5% reported persistent pain in one or two pelvic locations, 3.0% reported pelvic girdle syndrome and 0.5% reported severe pelvic girdle syndrome. The recovery rates decreased with increasing levels of pain severity in pregnancy. Being emotionally distressed at two time points during pregnancy was associated with the presence of pelvic girdle syndrome (adjusted OR 1.5, 95% CI 1.2–1.9) and severe pelvic girdle syndrome (adjusted OR 1.9, 95% CI 1.1–3.1), after adjustment for pain severity in pregnancy, other medical conditions, body mass index, age at menarche, previous low back pain, and smoking during pregnancy.

Conclusions  In this follow‐up of women with pelvic girdle pain in pregnancy, the recovery rates after delivery were high. Our findings suggest that the presence of emotional distress during pregnancy is independently associated with the persistence of pelvic girdle pain after delivery.
Pulmonary Fat Embolism—A Prospective Study within the Forensic Autopsy Collective of the Republic of Iceland
Authors: Voisard Matthias X. , Schweitzer Wolf , Jackowski Christian
Published: October 2012

In the last century, studies established the origin of pulmonary fat embolism (PFE) and identified mechanical trauma as main source for PFE. This prospective study focused on determining a possible influence of cardiopulmonary resuscitation (CPR), in the context of an aging population, on the occurrence of PFE. Lung tissue samples from 256 bodies were examined using the twin‐edged knife technique without preliminary fixation but after staining with Sudan III. PFE grading was determined according to Falzi and performed at a 10× magnification. For statistical analysis, bodies were grouped by age, gender, and putrefaction and categorized following whether they had experienced trauma, CPR, the combination of both, or no mechanical impact. There was a significant correlation of trauma, CPR, and the combination of both to PFE but no noticeable influence of gender or putrefaction. An age over 70 years promotes a PFE due to resuscitation.
Two‐year course of anxiety disorders: different across disorders or dimensions?
Authors: Hendriks Sanne M. , Spijker Jan , Licht Carmilla M. M. , Beekman Aartjan T. F. , Penninx Brenda W. J. H.
Published: October 2012

Objective

This study compares diagnostic and symptom course trajectories across different anxiety disorders, and examines the role of anxiety arousal vs. avoidance behaviour symptoms in course prediction.

Method

Data were from 834 subjects with a current anxiety disorder from the Netherlands Study of Depression and Anxiety (NESDA) who were re‐interviewed after 2 years. DSM‐IV‐based diagnostic interviews and Life Chart Interviews (LCI) were used to assess the diagnostic and symptom course trajectory over 2 years. Anxiety arousal and avoidance behaviour symptoms were measured with LCI, Beck Anxiety Inventory and Fear Questionnaire.

Results

Prognosis varied across disorders, with favourable remittance rates of 72.5% for panic disorder without agoraphobia and 69.7% for generalized anxiety disorder; gradually declining to 53.5% for social phobia and 52.7% for panic disorder with agoraphobia. Only 42.9% of those with multiple anxiety disorder remitted, and this group showed a more chronic course than pure anxiety disorders. Both baseline duration and severity were course predictors. Avoidance behaviour symptoms predicted the outcome better than anxiety arousal symptoms.

Conclusions

These data suggest that the specific anxiety disorders such as recognized by DSM‐IV are useful in predicting the outcome and that this may be determined largely by the relative severity of avoidance behaviour that patients have developed.
Need for closure and heuristic information processing: The moderating role of the ability to achieve the need for closure
Authors: Kossowska Małgorzata , Bar‐Tal Yoram
Published: October 2012

In contrast to the ample research that shows a positive relationship between the need for closure (NFC) and heuristic information processing, this research examines the hypothesis that this relationship is moderated by the ability to achieve closure (AAC), that is, the ability to use information‐processing strategies consistent with the level of NFC. Three different operationalizations of heuristic information processing were used: recall of information consistent with the impression (Study 1); pre‐decisional information search (Study 2); and stereotypic impression formation (Study 3). The results of the studies showed that there were positive relationships between NFC and heuristic information processing when participants assessed themselves as being able to use cognitive strategies consistent with their level of NFC (high AAC). For individuals with low AAC, the relationships were negative. Our data show that motivation–cognition interactions influence the information‐processing style.
Agreeableness, conscientiousness, and psychoticism: Distinctive influences of three personality dimensions in adolescence
Authors: Heaven Patrick C. L. , Ciarrochi Joseph , Leeson Peter , Barkus Emma
Published: October 2012

Researchers have suggested that the psychoticism (P) personality dimension of the Eysenck Personality Questionnaire may be largely redundant with the agreeableness (A) and conscientiousness (C) constructs of the five‐factor model. Little research has examined the distinctiveness of these constructs. We utilized a multi‐wave, multi‐method design to examine the ability of C, A, and P to uniquely predict a number of important outcomes amongst high school students. A total of 778 students (391 males, 387 females; mean age 15.41 years.) completed personality measures in Grade 10. Self‐reported self‐esteem, social support, health‐related behaviours, religious values as well as teachers' assessments of students, were collected 1 and 2 years later. A, C, and P were distinctive in their ability to predict these outcomes, after controlling for gender and socio‐economic status as well as Grade 10 extraversion, openness, and neuroticism. The individual P items explained unique variance over and above that explained by A and C. It was concluded that P is not merely the opposite of A and C. Implications for interventions are raised.
Children's use of addition to solve two‐digit subtraction problems
Authors: Peters Greet , De Smedt Bert , Torbeyns Joke , Ghesquière Pol , Verschaffel Lieven
Published: October 2012

Subtraction problems of the type M − S = ? can be solved with various mental calculation strategies. We investigated fourth‐ to sixth‐graders' use of the subtraction by addition strategy, first by fitting regression models to the reaction times of 32 two‐digit subtractions. These models represented three different strategy use patterns: the use of direct subtraction, subtraction by addition, and switching between the two strategies based on the magnitude of the subtrahend. Additionally, we compared performance on problems presented in two presentation formats, i.e., a subtraction format (81 − 37 = .) and an addition format (37 + . = 81). Both methods converged to the conclusion that children of all three grades switched between direct subtraction and subtraction by addition based on the combination of two features of the subtrahend: If the subtrahend was smaller than the difference, direct subtraction was the dominant strategy; if the subtrahend was larger than the difference, subtraction by addition was mainly used. However, this performance pattern was only observed when the numerical distance between subtrahend and difference was large. These findings indicate that theoretical models of children's strategy choices in subtraction should include the nature of the subtrahend as an important factor in strategy selection.
Performance goals in conflictual social interactions: Towards the distinction between two modes of relational conflict regulation
Authors: Sommet Nicolas , Darnon Céline , Mugny Gabriel , Quiamzade Alain , Pulfrey Caroline , Dompnier Benoît , Butera Fabrizio
Published: October 2012

Socio‐cognitive conflict has been defined as a situation of confrontation with a disagreeing other. Previous research suggests that individuals can regulate conflict in a relational way, namely by focusing on social comparison between relative levels of competences. Relational conflict regulation has been described as yielding particularly negative effects on social interactions and learning, but has been understudied. The present research addresses the question of the origin of relational conflict regulation by introducing a fundamental distinction between two types of regulation, one based on the affirmation of one's own point of view and the invalidation of the other's (i.e., ‘competitive’ regulation), the other corresponding to the protection of self‐competence via compliance (i.e., ‘protective’ regulation). Three studies show that these modes of relational conflict regulation result from the endorsement of distinct performance goals, respectively, performance‐approach goals (trying to outperform others) and performance‐avoidance goals (avoiding performing more poorly than others). Theoretical implications for the literature on both conflict regulation and achievement goals are discussed.
Chromogenic in situ Hybridization is a Reliable Alternative to Fluorescence in situ Hybridization for Diagnostic Testing of 1p and 19q Loss in Paraffin‐Embedded Gliomas
Authors: Lass Ulrike , Hartmann Christian , Capper David , Herold‐Mende Christel , von Deimling Andreas , Meiboom Maren , Mueller Wolf
Published: October 2012

Recent studies imply the importance of rapid and reliable diagnostic assessment of 1p/19q status in oligodendroglial tumors. To date, fluorescence in situ hybridization (FISH) is the most commonly applied technique. FISH, however, has several technical shortcomings that are suboptimal for diagnostic applications: results must be viewed in a fluorescence microscope, results are usually evaluated by a single investigator only, and signal fading excludes physical archiving. Also, in gliomas, the distinction of diffusely infiltrating tumor cells from reactively altered normal tissue may be challenging in fluorescence microscopy. Dual‐color chromogenic in situ hybridization (CISH) has started to replace FISH in some diagnostic tests performed in pathology. Here, we present the first single institute experience with a side‐by‐side analysis of 1p/19q FISH and CISH in a series of 42 consecutive gliomas. FISH and CISH produced identical results for 1p and 19q in 93% of cases (n = 39/42). Discrepant results were reevaluated by repeated FISH and a polymerase chain reaction (PCR)‐based microsatellite marker analysis for loss of heterozygosity. Reevaluation confirmed CISH data in all three cases. We conclude that CISH is a reliable alternative in 1p/19q testing in paraffin‐embedded tissues likely to be more sensitive to detect 1p/19q status than FISH analysis.
Identification of the internal anal opening and seton placement improves the outcome of deep postanal space abscess
Authors: Tan K.‐K. , Liu X. , Tsang C. B. , Koh D. C.
Published: October 2012

Aim

This study aimed to determine if successful seton placement at the initial drainage procedure improves outcomes in the management of deep postanal space abscesses.

Method

A retrospective review was performed of all patients who underwent initial drainage of a DPA space abscess between December 2002 and August 2010. A seton was placed through the internal opening if it could be identified.

Results

Thirty‐two patients of median age 41 (21–64) years formed the study group. Twenty‐four (75.0%) had a seton inserted at the initial drainage procedure. The patients underwent a total of 56 operations. The median interval from the initial to the final operation was 5 (2–18) months with 17 (70.8%) patients having the final operation within 6 months. In the 8 (25.0%) patients whose internal opening could not be found, 26 operations were required with a median interval from the initial to the final surgery of 11 (3–24) months. Patients who had a seton successfully inserted at drainage underwent significantly earlier definitive surgery and required fewer operations (P < 0.038).

Conclusion

Identification of an internal opening with placement of a seton at the initial drainage procedure is associated with earlier definitive surgery and fewer operations.
Muscle satellite cells are activated after exercise to exhaustion in Thoroughbred horses
Authors: Kawai M. , Aida H. , Hiraga A. , Miyata H.
Published: October 2012

Reasons for performing study

Although satellite cells are well known as muscle stem cells capable of adding myonuclei during muscle repair and hypertrophy, the response of satellite cells in horse muscles to a run to exhaustion is still unknown.

Objectives

To investigate the time course of satellite cell activation in Thoroughbred horse muscle after running to exhaustion. We hypothesised that this type of intense exercise would induce satellite cell activation in skeletal muscle similar to a resistance exercise.

Methods

Nine de‐trained Thoroughbred horses (6 geldings and 3 mares) aged 3–6 years were studied. Biopsy samples were taken from the gluteus medius muscle of the horses before and 1 min, 3 h, 1 day, 3 days, 1 week and 2 weeks after a treadmill run to exhaustion. The numbers of satellite cells for each fibre type were determined by using immunofluorescence staining. Total RNA was extracted from these samples, and the expressions of interleukin (IL)‐6, paired box transcriptional factor (Pax) 7, myogenic differentiation 1 (MyoD), myogenin, proliferating cell nuclear antigen (PCNA), insulin‐like growth factor (IGF)‐I and hepatocyte growth factor (HGF) mRNA were analysed using real‐time reverse transcription‐PCR.

Results

The numbers of satellite cells were significantly increased in type I and IIa fibres at 1 week and in type IIa/x fibre at 2 weeks post exercise. The expression of IL‐6 mRNA increased significantly by 3 h post exercise. The expression of PCNA mRNA also increased by 1 day after running, indicating that running can initiate satellite cell proliferation. The expression of Pax7, MyoD, myogenin, IGF‐I and HGF mRNA peaked at 1 week post exercise.

Conclusion

Satellite cell activation and proliferation could be enhanced after a run to exhaustion without detectable injury as assessed by the histochemical analysis. Understanding the response of satellite cell activation to running exercise provides fundamental information about the skeletal muscle adaptation in Thoroughbred horses.
Use of continuous positive airway pressure (CPAP) to optimise oxygenation in anaesthetised horses – a clinical study
Authors: Mosing M. , Rysnik M. , Bardell D. , Cripps P. J. , MacFarlane P.
Published: October 2012

Reasons for performing study

Hypoxaemia is a common problem during equine anaesthesia. Continuous positive airway pressure (CPAP) is a ventilation mode routinely employed in man to overcome hypoxaemia but has not been objectively assessed in horses.

Objectives

To test the effects of CPAP on oxygenation and its indices in anaesthetised horses in a clinical setting.

Methods

Twenty‐four healthy horses requiring anaesthesia in dorsal recumbency were anaesthetised using a standard protocol. Following orotracheal intubation and connection to an anaesthetic machine capable of applying CPAP, horses were randomly allocated to ventilate at physiological airway pressure measured at the airway opening (Group PAP) or to receive CPAP of 8 cmH2O (Group CPAP). Arterial blood gas analysis was performed as soon as arterial cannulation was achieved and 30, 60 and 90 min after induction. If PaCO2 increased above 9.31 kPa controlled ventilation was initiated. Groups were compared using a general linear model.

Results

Horses receiving CPAP had significantly higher PaO2 and calculated oxygen indices than horses receiving PAP. No significant differences in ventilation indices were observed between the 2 groups. Eight horses receiving PAP and 5 receiving CPAP required controlled ventilation. No differences in dobutamine requirements or mean arterial pressures were recorded.

Conclusions

Continuous positive airway pressure of 8 cmH2O improved oxygenation indices in dorsally recumbent horses without significantly influencing ventilation.

Potential relevance

Continuous positive airway pressure reduces the incidence of hypoxaemia in anaesthetised horses. Further research is warranted to elucidate the effects of CPAP on the cardiovascular system.
Insulin solubility transitions by pH‐dependent interactions with proinsulin C‐peptide
Authors: Landreh Michael , Alvelius Gunvor , Willander Hanna , Stukenborg Jan‐Bernd , Söder Olle , Johansson Jan , Jörnvall Hans
Published: October 2012

Proinsulin processing into insulin and C‐peptide in the secretory granules of the pancreatic β‐cells occurs under mildly acidic conditions and at high peptide concentrations (> 10 mm). Mature insulin has reduced solubility and a propensity to adopt an amyloid‐like structure, but is physiologically released as a mixture of a zinc‐containing core and a zinc‐free, C‐peptide‐rich fluid phase. C‐peptide is known to function in the insulin secretion, but its exact mode of interaction is not established. We now demonstrate that C‐peptide in sub‐stoichiometric amount versus insulin coprecipitates with insulin at the pH found in secretory vesicles. Precipitation is reversible and the precipitate is dissolved by elevation of the pH. This effect was found to be dependent on relatively conserved glutamate residues in the otherwise poorly conserved C‐peptide. Together, the data show that C‐peptide has the ability to influence insulin solubility. The physiological pH changes between insulin processing and release sites may therefore affect the quaternary structure of insulin, as well as the phase transitions during insulin sorting and secretion.

Structured digital abstract

Insulin and C-peptide bind by molecular sieving (View Interaction: 1, 2)

C-peptide and Insulin bind by dynamic light scattering (View Interaction: 1, 2)

C-peptide and Insulin bind by fluorescence technology (View Interaction: 1, 2, 3, 4)