bluuebunny/crossref_metadata_2025 huggingface dataset:
The isolated C-terminus of polycystin-1 promotes increased ATP-stimulated chloride secretion in a collecting duct cell line
Authors: HOOPER Kimberly M. , UNWIN Robert J. , SUTTERS Michael
Published: August 2015

Cyst expansion in autosomal dominant polycystic kidney disease (ADPKD) requires accumulation of fluid into the cyst lumen, which is probably driven by aberrant chloride secretion by the cyst lining epithelium. Extracellular ATP is a potent stimulus for chloride secretion in many epithelial systems, and provides a plausible mechanism for secretion in ADPKD. Therefore the link between polycystin-1 and ATP-stimulated chloride secretion was investigated in the M1 cortical collecting duct cell line. M1 cells were stably transfected with a glucocorticoid-inducible cytoplasmic C-terminal polycystin-1 construct fused to a membrane expression cassette. Induction of fusion protein expression was associated with augmentation of ATP-stimulated transepithelial chloride secretion. After nystatin-induced permeabilization of the basolateral membrane, it was determined that expression of the polycystin fusion protein modulated an ATP-responsive apical chloride conductance. It is concluded that up-regulation of ATP-stimulated chloride secretion might play a significant role in cyst expansion in ADPKD.
Augmented sympathetic neural response to simulated obstructive apnoea in human heart failure
Authors: BRADLEY T. Douglas , TKACOVA Ruzena , HALL Michael J. , ANDO Shin-ichi , FLORAS John S.
Published: August 2015

Sleep apnoea in heart failure increases mortality risk, possibly as a result of greater activation of the sympathetic nervous system. In healthy subjects, simulated central apnoeas (holding breath) and obstructive apnoeas (Mueller manoeuvres) increase muscle sympathetic activity equally, primarily through chemoreceptor stimulation. In heart failure, however, Mueller manoeuvres cause greater reductions in blood pressure than breath holds. We hypothesized that in heart failure, the summation of arterial baroreceptor unloading and chemoreceptor stimulation would increase sympathetic activity more during obstructive than central apnoeas. Healthy human subjects and heart failure patients (seven of each) performed 15-s breath holds and 15-s Mueller manoeuvres. Breath holds evoked a progressive increase in muscle sympathetic nerve activity in both groups, but had no effect on blood pressure. In healthy subjects, breath holds and Mueller manoeuvres caused equal peaks in sympathetic activity. In contrast, in heart failure patients, Mueller manoeuvres caused a progressive decrease in blood pressure (P<0.05) and greater increases in sympathetic activity than breath holds (P<0.01). In heart failure, simulated obstructive apnoea elicits greater increases in sympathetic activity than simulated central apnoea, due to its additional hypotensive effect. These present findings offer novel insight into the potential role of sleep apnoea in augmenting sympathetic activity and accelerating disease progression in heart failure.
Cigarette smoking is associated with an acute impairment of microvascular function in humans
Authors: IJZERMAN Richard G. , SERNE Erik H. , WEISSENBRUCH Mirjam M. van , JONGH Renate T. de , STEHOUWER Coen D.A.
Published: August 2015

An effect on microvascular function has been proposed as a possible mechanism explaining the association of acute smoking with increased blood pressure and decreased insulin sensitivity. However, the effects of smoking on microvascular function have not been studied. We have investigated the acute effects of smoking on microvascular function in 12 healthy smokers. Before and after smoking a cigarette, we measured heart rate, blood pressure and capillary recruitment during peak reactive hyperaemia. We also measured endothelium-dependent and endothelium-independent vasodilatation of the skin microcirculation with iontophoresis of acetylcholine and sodium nitroprusside respectively combined with laser Doppler fluxmetry. To exclude non-specific changes, a control study with sham smoking was performed. The smoking and sham smoking studies were conducted in a randomized order. Compared with sham smoking, acute smoking caused increases in heart rate (smoking, 9.3±4.1beats/min; sham, -1.3±3.0beats/min; P<0.001) and systolic blood pressure (smoking, 6.3±8.8mmHg; sham, 0.8±4.4mmHg; P<0.05); decreases in absolute (smoking, -4.9±6.9 per mm2; sham, 0.8±2.1 per mm2; P = 0.01) and relative (smoking, -13.8±21.4%; sham, 1.9±6.9%; P = 0.02) capillary recruitment during peak reactive hyperaemia; and decreases in absolute [smoking, -62.4±47.7 perfusion units (PU); sham, -30.8±32.6PU; P = 0.04] and relative (smoking, -147±163%; sham, 32±225%; P = 0.07) vasodilatation caused by acetylcholine. Absolute (smoking, -31.6±58.5PU; sham, -8.4±44.0PU; P = 0.3) and relative (smoking, -50.2±219.0%; sham, -17.1±139%; P = 0.7) vasodilatation caused by sodium nitroprusside were not affected. Thus acute smoking is associated with impaired capillary recruitment during peak reactive hyperaemia and impaired microvascular endothelium-dependent vasodilatation. These findings may explain the increased blood pressure and decreased insulin sensitivity that have been observed after acute smoking.
Acute pulmonary oedema: rare causes and possible mechanisms
Authors: HSU Yung-Hsiang , KAO Shang Jyh , LEE Ru-Ping , CHEN Hsing I.
Published: August 2015

Acute pulmonary oedema usually has a fatal outcome. In this clinical report, we present rare cases of pulmonary oedema that were associated with Japanese B encephalitis, lymphangitis in breast carcinoma, fat embolism due to long-bone fracture, and the rupture of cerebral mycotic aneurysms. A total of 18 patients in the four disease categories were collected in two teaching hospitals in Taipei and Hualien. Upon admission, routine and specific examinations were taken and all patients showed clear lungs by chest X-ray; however, signs of acute pulmonary oedema occurred within 7 days. After resuscitation, all patients died of acute pulmonary oedema. In patients with fat embolism, the levels of non-esterified plasma fatty acids, cGMP, 5-hydroxytryptamine (serotonin) and nitrates/nitrites were increased during pulmonary oedema. Immunohistochemical staining revealed virus infection and neuronal death, predominantly in the medial, ventral and caudal medulla in cases of Japanese B encephalitis. The pulmonary oedema due to central sympathetic activation in Japanese B encephalitis may be related to destruction of depressor mechanisms in the medulla. The rupture of mycotic aneurysms is known to cause cerebral compression that results in acute pulmonary oedema. Blockade of lymphatics, capillaries and venules in breast carcinoma with lymphangitis causes the development of rapid lung oedema. The pathogenesis of pulmonary oedema is much more complicated in fat embolism. Mediators such as cGMP, 5-hydroxytryptamine, nitric oxide and presumably other chemical substances may also be involved.
Sodium/lithium countertransport and intracellular calcium concentration in patients with essential hypertension and coronary heart disease
Authors: GRUSKA Sybille , JENDRAL Ingo , RETTIG Rainer , KRAATZ Günter
Published: August 2015

The present study was designed to test the hypothesis that enhanced intracellular calcium signalling and increased sodium/lithium countertransport (Na+/Li+ CT) activity may be associated with coronary heart disease (CHD) in non-diabetic patients with essential hypertension. Platelet-activating factor (PAF)-evoked rises in the intracellular calcium concentration ([Ca2+]i) were measured in Epstein–Barr-virus-immortalized lymphoblasts from 62 hypertensive patients with CHD and 34 patients without CHD. Na+/Li+ CT activity was assessed in erythrocytes from 80 hypertensive patients with CHD and 46 patients without CHD. Baseline values of unstimulated and PAF-stimulated [Ca2+]i were not significantly different between hypertensive subjects with (baseline, 126±5nmol/l; stimulated, 550±43nmol/l) and without (baseline, 125±5nmol/l; stimulated, 654±105nmol/l) CHD. Similarly, Na+/Li+ CT activity was not significantly different between the two groups (patients with CHD, 219±8µmol·l-1·h-1; patients without CHD, 234±10µmol·l-1·h-1). We conclude that intracellular signal transduction, as indicated by PAF-induced rises in [Ca2+]i and Na+/Li+ CT activity, is not associated with an increased risk of CHD in non-diabetic patients with essential hypertension.
High-dose heparin fails to improve acute lung injury following smoke inhalation in sheep
Authors: MURAKAMI Kazunori , ENKHBAATAR Perenlei , SHIMODA Katsumi , MIZUTANI Akio , COX Robert A. , SCHMALSTIEG Frank C. , JODOIN Jeffrey M. , HAWKINS Hal K. , TRABER Lillian D. , TRABER Daniel L.
Published: August 2015

Thrombin is involved in various inflammatory responses. In sepsis, coagulation abnormalities are major complications. Acute lung injury is one of the most life-threatening problems that can result from sepsis. We hypothesized that high-dose heparin might be effective in attenuating acute lung injury in our sepsis model. Female sheep (n = 16) were surgically prepared for the study. After a tracheotomy, 48 breaths of cotton smoke (<40°C) were insufflated into the airway. Afterwards, live Pseudomonas aeruginosa (5×1011 colony-forming units) bacteria were instilled into the lung. All sheep were ventilated mechanically with 100% O2, and were divided into three groups: a heparin infusion group (n = 6), a Ringer's lactate infusion group (n = 6), and a sham-injury group (n = 4; surgically prepared in the same fashion but receiving no inhalation injury or bacteria). The treatment was started 1h after the insult, and was continued thereafter for 24h. The dose of heparin was adjusted by monitoring to target an activated clotting time of between 300 and 400s (baseline = approx. 150s). Sheep exposed to lung injury presented with typical hyperdynamic cardiovascular changes, including an increased cardiac output and a fall in systemic vascular resistance. There was a decrease in the arterial partial pressure of O2. In conclusion, high-dose heparin did not prevent lung dysfunction in this model, in which acute lung injury was induced by combined smoke and septic challenge.
Evidence of impaired microvascular function in pre-eclampsia: a non-invasive study
Authors: ANIM-NYAME N. , GAMBLE J. , SOORANNA S.R. , JOHNSON M.R. , SULLIVAN M.H. , STEER P.J.
Published: August 2015

The clinical presentation of pre-eclampsia suggests that microvascular dysfunction may play a role in the maternal manifestations of the disease. Isovolumetric venous pressure (PVi) is an index of microvascular function, reflecting local plasma colloid osmotic (oncotic) pressure, and is abnormal in clinical conditions with microvascular dysfunction. We hypothesized that, in pre-eclampsia, post-capillary margination of neutrophils would increase post-capillary resistance, and therefore PVi. A small cumulative step strain-gauge plethysmography protocol was used to compare PVi in 18 women with pre-eclampsia, 16 normal pregnant women and 17 non-pregnant controls. Circulating levels of vascular cell-adhesion molecule-1 (VCAM-1), intercellular cell-adhesion molecule-1 (ICAM-1) and E-selectin, and neutrophil elastase, were measured to assess endothelial and neutrophil activation respectively. PVi was significantly greater in the pre-eclampsia group, relative to the normal pregnant and non-pregnant controls (P<0.001, ANOVA, for both comparisons). PVi was significantly lower during normal pregnancy compared with the non-pregnant controls (P = 0.001). Plasma levels of neutrophil elastase, VCAM-1, ICAM-1 and E-selectin (P = 0.001) were significantly greater in the pre-eclamptics than the controls. Significant positive correlations were observed between PVi and neutrophil elastase (r = 0.71, P = 0.001), VCAM-1 (r = 0.52, P = 0.03), ICAM-1 (r = 0.67, P = 0.002), E-selectin (r = 0.69, P = 0.001), uric acid levels (r = 0.54, P = 0.02) and haematocrit (r = 0.64, P = 0.004) in pre-eclampsia. The relationship with the platelet count was negative (r =-0.65, P = 0.003). No significant correlations were observed between PVi and maternal age, gestational age, total protein, albumin, diastolic blood pressures, age, body mass index and infant birth mass in the normal pregnant and non-pregnant controls. These data suggest that microvascular dysfunction occurs in pre-eclampsia, and that it is related to alterations in endothelial cell and neutrophil activation.
C-reactive protein: a marker or a player?
Authors: Nyström Thomas
Published: August 2015

It has been suggested that Type 2 diabetes may, in part, be precipitated or accelerated by an acute-phase reaction as part of the innate immune response, in which large amounts of cytokines are released from adipose tissue, creating a low-grade inflammatory milieu. There is also firm evidence that atherosclerosis is an immune-mediated inflammatory disease. Therefore it is reasonable to imply that low-grade inflammation is an important pathogenetic factor in atherosclerosis and cardiovascular events in patients with Type 2 diabetes. Over the last few years, there have been a lot of promising clinical markers proposed to link inflammation and atherosclerosis. Of these markers, hs-CRP (high-sensitivity C-reactive protein) might be a prognostic marker for further cardiovascular events, although this has been refuted recently. In this issue of Clinical Science, Castoldi and co-workers have demonstrated that, in patients with Type 2 diabetes categorized into low (<1.0 mg/l), medium (1.0–3.0 mg/l) and high (>3.0 mg/l) hs-CRP groups, serum levels of hs-CRP correlated with lipopolysaccharide-stimulated release of interleukin-1β and interleukin-6 in whole blood. This finding may indicate that low-grade inflammatory activity might influence cytokine production in these patients.
Cellular and molecular biology of Neisseria meningitidis colonization and invasive disease
Authors: Hill Darryl J. , Griffiths Natalie J. , Borodina Elena , Virji Mumtaz
Published: August 2015

The human species is the only natural host of Neisseria meningitidis, an important cause of bacterial meningitis globally, and, despite its association with devastating diseases, N. meningitidis is a commensal organism found frequently in the respiratory tract of healthy individuals. To date, antibiotic resistance is relatively uncommon in N. meningitidis isolates but, due to the rapid onset of disease in susceptible hosts, the mortality rate remains approx. 10%. Additionally, patients who survive meningococcal disease often endure numerous debilitating sequelae. N. meningitidis strains are classified primarily into serogroups based on the type of polysaccharide capsule expressed. In total, 13 serogroups have been described; however, the majority of disease is caused by strains belonging to one of only five serogroups. Although vaccines have been developed against some of these, a universal meningococcal vaccine remains a challenge due to successful immune evasion strategies of the organism, including mimicry of host structures as well as frequent antigenic variation. N. meningitidis express a range of virulence factors including capsular polysaccharide, lipopolysaccharide and a number of surface-expressed adhesive proteins. Variation of these surface structures is necessary for meningococci to evade killing by host defence mechanisms. Nonetheless, adhesion to host cells and tissues needs to be maintained to enable colonization and ensure bacterial survival in the niche. The aims of the present review are to provide a brief outline of meningococcal carriage, disease and burden to society. With this background, we discuss several bacterial strategies that may enable its survival in the human respiratory tract during colonization and in the blood during infection. We also examine several known meningococcal adhesion mechanisms and conclude with a section on the potential processes that may operate in vivo as meningococci progress from the respiratory niche through the blood to reach the central nervous system.
Conducting an Augmentative and Alternative Communication Assessment as a School-Based Speech-Language Pathologist: A Collaborative Experience
Authors: Dodd Janet , Schaefer Alicia , Rothbart Aaron
Published: August 2015

In addition to providing services to children who demonstrate speech and language impairments, it is within a speech-language pathologist's (SLP's) scope of practice to “recognize and hold paramount the needs and interests of individuals who may benefit from AAC [Augmentative and Alternative Communication]” (American Speech-Language-Hearing Association (ASHA), 2005, Position Statement section, para. 3). However, in spite of nearly one-half of all school-based SLPs reporting they provide services to nonverbal students who utilize AAC systems (ASHA 2012; Kent-Walsh, Stark, & Binger, 2008; Proctor & Oswalt, 2008) many SLPs across the country still do not feel adequately trained to assess and provide therapy services to these children (Costigan & Light, 2010; Kent-Walsh et al., 2008; Light, Drager, Currall, & Roberts, 2012). It is becoming increasingly necessary for all SLPs to assume responsibilities in the AAC process. The case study presented in this article illustrates the collaborative process of conducting an AAC assessment for a preschool-aged child.
Integratable trench MOSFET with ultra‐low specific on‐resistance
Authors: Yin Chao , Wei Jie , Zhou Kun , Luo Xiaorong
Published: August 2015

A novel integratable metal–oxide–semiconductor field‐effect transistor (MOSFET) with a trench source (TS) and a trench gate (TG) (TS–TG MOSFET) is proposed. The TS and TG cause a strong assistant depletion effect and thus dramatically increase the N‐drift doping concentration (Nd). Moreover, an accumulation layer beside the TG is formed and offers a continuous low‐resistance path in the on‐state. Therefore, the novel MOSFET effectively reduces specific on‐resistance (Ron,sp). The TS–TG MOSFET not only has the merits of low Ron,sp and the easy parallel connection of vertical double‐diffused MOS, but also possesses the advantage of ease of integration like the LDMOS. The breakdown voltage (BV) of 61 V and the Ron,sp of 0.133 mΩ cm2 are obtained for the TS–TG MOSFET, with a significant optimised trade‐off between Ron,sp and BV.
Microfabrication of conical microfunnels for drug delivery applications
Authors: Liu L.W.Y. , Virdee B.S. , Inal J. , Steer M.B.
Published: August 2015

A cost‐effective fabrication methodology for the mass production of conical microfunnels for drug delivery applications is presented. The fabrication methodology originates from a technique previously used for fabricating suspended or hollow microstructures. The process comprises six stages: in stage 1, a UV‐opaque resin substrate is formed by mixing photocurable SU‐8 with a UV‐opaque impurity; in stage 2, an embossing stamp with an array of microrods is fabricated; in stage 3, the upper surface of the UV‐opaque resin substrate (from the first stage) is mechanically deformed by stamping with the embossing stamp from stage 2; in stage 4, the regions in which microfunnels are photolithographically defined are selectively exposed to UV light; in stage 5, the wafer from stage 4 is subjected to heat and then developed in 1‐methoxy‐2‐propanol acetate; finally, a hole on the tip of each microfunnel is formed by dry etching with oxygen plasma. The sharpness of the funnel tips can be flexibly adjusted by changing the stroke speed of the stamping in stage 3. The overall process can be carried out photolithographically with conventional photolithographic equipment. Using the proposed fabrication methodology, a matrix of polymeric microfunnels tapering from the base measuring 300 μm to the tip measuring 50 μm over a funnel height of 100 μm has been fabricated. Each fabricated microfunnel features a wide base and a sharp tip so that it has sufficient mechanical strength and sharpness to pierce the human skin. The conical geometry used in this study had a volume in excess of 24.4 nl.
Titanium oxide vertical resistive random‐access memory device
Authors: Fryauf David M. , Norris Kate J. , Zhang Junce , Wang Shih‐Yuan , Kobayashi Nobuhiko P.
Published: August 2015

Pt/TiO2/Pt vertical resistive random‐access memory switching devices were fabricated in a vertical three‐dimensional structure by combining conventional photolithography, electron‐beam evaporation for electrodes and atomic layer deposition for dielectric layers. The active switching cross‐sectional area was ∼0.02 µm2, which is comparable to nanosized devices that require more elaborative fabrication processes. Structural integrity and electrical characteristics of the vertical memory device were analysed by cross‐sectional scanning, transmission electron microscopy and current–voltage characteristics.
Al2O3 and Sn/Al2O3 nanowires: fabrication and characterisation
Authors: Shaban Mohamed , Ali Mona , Abdel‐Hady Kamal , Hamdy Hany
Published: August 2015

Self‐ordered anodised aluminium oxide membranes can be used as a base for the growth of different nanoarrays. In this reported work, an efficient and effective method is implemented to fabricate highly ordered alumina nanowires (ANWs) covered with a uniform shell of 12 ± 2 nm Sn nanoparticles (Sn/ANWs). A two‐step anodisation process followed by a selective etching process was used to prepare highly ordered ANWs with diameters smaller than 36 nm. The thermal evaporation technique was used to ensure the deposition of a Sn nanoshell on the fabricated nanowires. The fabricated nanostructures were characterised by energy‐dispersive X‐ray spectroscopy, X‐ray diffraction, field emission‐scanning electron microscopy and an ultraviolet–visible–near‐infrared spectrophotometer. Analysis of the scanning electron microscopy images showed that the etching rate is 0.73 nm/min and ANWs are obtained after etching the membrane for 110 min. The measured reflection spectra revealed that Sn/ANWs exhibit a redshift of the UV absorption band relative to the ANWs and a reflectance of nearly 100% in the near‐infrared region. For optical comparison, glass slides were coated with Sn under the same conditions for 90 and 120 s. The reflection spectrum of the 120 s Sn‐coated glass slide shows three modes at 210, 296 and 700 nm because of the excitation and interference of plasmonic waves.
Transient Elastography to Assess the Cervical Ripening during Pregnancy: A Preliminary Study
Authors: Peralta Laura , Molina Francisca , Melchor Juan , Gómez Luisa , Massó Paloma , Florido Jesús , Rus Guillermo
Published: August 2015

Purpose To explore the feasibility of transient elastography (TE) to quantify cervical stiffness changes during normal pregnancy and its spatial variability.

Materials and Methods TE was used to quantify the cervical stiffness in four anatomical regions. 42 women between 17 and 43 years of age and at 6 – 41 weeks of gestation were studied. The stiffness was related to gestational age at the time of examination, interval from ultrasound examination to delivery and cervical length to evaluate the potential of TE to assess cervical ripening. In addition, a sensitivity analysis based on Cronbach’s alpha coefficient was carried out to assess the concordance between inter/intra-operator measurements.

Results There were significant correlations between cervical stiffness measured in the four regions with gestational age and the remaining time for delivery. Results confirm stiffness variability within the cervix. No significant association was found between cervical length and stiffness in the four ROIs. Associations between gestational age and remaining time for delivery with cervical length present weaker correlations than with cervical stiffness. The external part of the cervix was significantly softer than the internal one, and these stiffness values vary significantly in the anterior compared to the posterior cervix. The measurements taken by the same and by two different observers for different regions in the cervix were reliable and reproducible.

Conclusion It is feasible to objectively quantify the decrease of cervical stiffness correlated to gestational age. Transient elastography is a valuable promising tool to provide additional information on the process of cervical effacement to that obtained from digital examination and conventional ultrasound. Further studies are needed to assess the feasibility of the technique in obstetric clinical applications, such as prediction of preterm birth or success in labor induction.
Influence of substituents on the nature of metal⋯π interaction and its cooperativity with halogen bond
Authors: Gao Meng , Cheng Jianbo , Yang Xin , Li Wenzuo , Xiao Bo , Li Qingzhong
Published: August 2015

High-level quantum chemical calculations have been performed to investigate the influence of substituents on the metal—π interaction and its cooperative effect with halogen bond in C2X4⋯MCN⋯ClF (X = H, CN, CH3; M = Cu, Ag, Au). The strong electron-withdrawing group CN weakens the metal—π covalent interaction, while the weak electron-withdrawing group CH3 strengthens it. The metal—π covalent interaction is dominated by electrostatic energy although the AuCN complex has approximately equal electrostatic and polarization contributions. However, the metal—π covalent interaction is governed by polarization energy due to the CN substitution. A cooperative effect is found for the halogen bond and metal—π interactions in C2H4⋯MCN⋯ClF, while a diminutive effect occurs in the triads by the CN substituent. Orbital interaction analysis indicates that the strong electron-withdrawing group CN causes the C=C group vary from a stronger donor orbital to a stronger acceptor orbital.
Theoretical investigation of the dynamics of O(1D→3P) electronic quenching by collision with Xe
Authors: Dagdigian Paul J. , Alexander Millard H. , Kłos Jacek
Published: August 2015

We present the quantum close-coupling treatment of spin-orbit induced transitions between the 1D and 3P states of an atom in collisions with a closed-shell spherical partner. In the particular case of O colliding with Xe, we used electronic structure calculations to compute the relevant potential energy curves and spin-orbit coupling matrix elements. We then carried out quantum scattering calculations of integral and differential quenching cross sections as functions of the collision energy. The calculated differential cross sections for electronic quenching are in reasonable agreement with measurements [Garofalo et al., J. Chem. Phys. 143, 054307 (2015)]. The differential cross sections exhibit pronounced oscillations as a function of the scattering angle. By a semiclassical analysis, we show that these oscillations result from quantum mechanical interference between two classical paths.
Electronic quenching of O(1D) by Xe: Oscillations in the product angular distribution and their dependence on collision energy
Authors: Garofalo Lauren A. , Smith Mica C. , Dagdigian Paul J. , Kłos Jacek , Alexander Millard H. , Boering Kristie A. , Lin Jim Jr-Min
Published: August 2015

The dynamics of the O(1D) + Xe electronic quenching reaction was investigated in a crossed beam experiment at four collision energies. Marked large-scale oscillations in the differential cross sections were observed for the inelastic scattering products, O(3P) and Xe. The shape and relative phases of the oscillatory structure depend strongly on collision energy. Comparison of the experimental results with time-independent scattering calculations shows qualitatively that this behavior is caused by Stueckelberg interferences, for which the quantum phases of the multiple reaction pathways accessible during electronic quenching constructively and destructively interfere.
Magnetoelectric coupling and spin-dependent tunneling in Fe/PbTiO3/Fe multiferroic heterostructure with a Ni monolayer inserted at one interface
Authors: Dai Jian-Qing , Zhang Hu , Song Yu-Min
Published: August 2015

We report on first-principles calculations of a Ni monolayer inserted at one interface in the epitaxial Fe/PbTiO3/Fe multiferroic heterostructure, focusing on the magnetoelectric coupling and the spin-dependent transport properties. The results of magnetoelectric coupling calculations reveal an attractive approach to realize cumulative magnetoelectric effects in the ferromagnetic/ferroelectric/ferromagnetic superlattices. The underlying physics is attributed to the combinations of several different magnetoelectric coupling mechanisms such as interface bonding, spin-dependent screening, and different types of magnetic interactions. We also demonstrate that inserting a Ni monolayer at one interface in the Fe/PbTiO3/Fe multiferroic tunnel junction is an efficient method to produce considerable tunneling electroresistance effect by modifying the tunnel potential barrier and the interfacial electronic structure. Furthermore, coexistence of tunneling magnetoresistance and tunneling electroresistance leads to the emergence of four distinct resistance states, which can be served as a multistate-storage device. The complicated influencing factors including bulk properties of the ferromagnetic electrodes, decay rates of the evanescent states in the tunnel barrier, and the specific interfacial electronic structure provide us promising opportunities to design novel multiferroic tunnel junctions with excellent performances.
Ultrafast spin-switching of a ferrimagnetic alloy at room temperature traced by resonant magneto-optical Kerr effect using a seeded free electron laser
Authors: Yamamoto Sh. , Taguchi M. , Someya T. , Kubota Y. , Ito S. , Wadati H. , Fujisawa M. , Capotondi F. , Pedersoli E. , Manfredda M. , Raimondi L. , Kiskinova M. , Fujii J. , Moras P. , Tsuyama T. , Nakamura T. , Kato T. , Higashide T. , Iwata S. , Yamamoto S. , Shin S. , Matsuda I.
Published: August 2015

Ultrafast magnetization reversal of a ferrimagnetic metallic alloy GdFeCo was investigated by time-resolved resonant magneto-optical Kerr effect measurements using a seeded free electron laser. The GdFeCo alloy was pumped by a linearly polarized optical laser pulse, and the following temporal evolution of the magnetization of Fe in GdFeCo was element-selectively traced by a probe free electron laser pulse with a photon energy tuned to the Fe M-edge. The results have been measured using rotating analyzer ellipsometry method and confirmed magnetization switching caused by ultrafast heating.
Ultra-violet absorption induced modifications in bulk and nanoscale electrical transport properties of Al-doped ZnO thin films
Authors: Kumar Mohit , Basu Tanmoy , Som Tapobrata
Published: August 2015

Using conductive atomic force microscopy and Kelvin probe force microscopy, we study local electrical transport properties in aluminum-doped zinc oxide (ZnO:Al or AZO) thin films. Current mapping shows a spatial variation in conductivity which corroborates well with the local mapping of donor concentration (∼1020 cm−3). In addition, a strong enhancement in the local current at grains is observed after exposing the film to ultra-violet (UV) light which is attributed to persistent photocurrent. Further, it is shown that UV absorption gives a smooth conduction in AZO film which in turn gives rise to an improvement in the bulk photoresponsivity of an n-AZO/p-Si heterojunction diode. This finding is in contrast to the belief that UV absorption in an AZO layer leads to an optical loss for the underneath absorbing layer of a heterojunction solar cell.
Nature of the first-order liquid-liquid phase transition in supercooled silicon
Authors: Zhao G. , Yu Y. J. , Tan X. M.
Published: August 2015

The first-order liquid-liquid phase transition in supercooled Si is revisited by long-time first-principle molecular dynamics simulations. As the focus of the present paper, its nature is revealed by analyzing the inherent structures of low-density liquid (LDL) and high-density liquid (HDL). Our results show that it is a transition between a sp3-hybridization LDL and a white-tin-like HDL. This uncovers the origin of the semimetal-metal transition accompanying it and also proves that HDL is the metastable extension of high temperature equilibrium liquid into the supercooled regime. The pressure-temperature diagram of supercooled Si thus can be regarded in some respects as shifted reflection of its crystalline phase diagram.
Temperature dependence of frequency dispersion in III–V metal-oxide-semiconductor C-V and the capture/emission process of border traps
Authors: Vais Abhitosh , Lin Han-Chung , Dou Chunmeng , Martens Koen , Ivanov Tsvetan , Xie Qi , Tang Fu , Givens Michael , Maes Jan , Collaert Nadine , Raskin Jean-Pierre , DeMeyer Kristin , Thean Aaron
Published: August 2015

This paper presents a detailed investigation of the temperature dependence of frequency dispersion observed in capacitance-voltage (C-V) measurements of III-V metal-oxide-semiconductor (MOS) devices. The dispersion in the accumulation region of the capacitance data is found to change from 4%–9% (per decade frequency) to ∼0% when the temperature is reduced from 300 K to 4 K in a wide range of MOS capacitors with different gate dielectrics and III-V substrates. We show that such significant temperature dependence of C-V frequency dispersion cannot be due to the temperature dependence of channel electrostatics, i.e., carrier density and surface potential. We also show that the temperature dependence of frequency dispersion, and hence, the capture/emission process of border traps can be modeled by a combination of tunneling and a “temperature-activated” process described by a non-radiative multi-phonon model, instead of a widely believed single-step elastic tunneling process.
Characterisation of multi roof tile-shaped out-of-plane vibrational modes in aluminium-nitride-actuated self-sensing micro-resonators in liquid media
Authors: Kucera Martin , Wistrela Elisabeth , Pfusterschmied Georg , Ruiz-Díez Víctor , Sánchez-Rojas José Luis , Schalko Johannes , Bittner Achim , Schmid Ulrich
Published: August 2015

This letter reports on higher orders of an advanced out-of-plane bending mode in aluminium-nitride (AlN)-actuated cantilever plates achieving the highest quality factors (Q-factor) of cantilever-based MEMS (micro electromechanical system) resonators in liquids up to now. Devices based on a 20 μm thick silicon cantilever were fabricated and characterised by optical and electrical measurements in air and in different liquids. Furthermore, finite element method eigenmode analyses were performed, showing an excellent agreement with the measured mode shape and the electrical characteristics. The highest Q-factor was achieved in deionised water with Q = 366, operated at the 10th order mode at a resonance frequency less than 4 MHz. This is the highest value ever measured in liquid media with a cantilever-based MEMS resonator up to now and exceeds the Q-factors of state of the art resonators in liquids in the given resonance frequency range by a factor of about 4. Furthermore, the strain related conductance peak of the multi roof tile-shaped modes is superior, showing great potential for further electrode design optimisation. Compared to common out-of-plane bending modes, this combination of most beneficial properties is unique, making this type of vibration mode the first choice for a large variety of resonator-based liquid-phase sensing applications.
Reducing contact resistance in ferroelectric organic transistors by buffering the semiconductor/dielectric interface
Authors: Sun Huabin , Yin Yao , Wang Qijing , Jun Qian , Wang Yu , Tsukagoshi Kazuhito , Wang Xizhang , Hu Zheng , Pan Lijia , Zheng Youdou , Shi Yi , Li Yun
Published: August 2015

The reduction of contact resistance in ferroelectric organic field-effect transistors (Fe-OFETs) by buffering the interfacial polarization fluctuation was reported. An ultrathin poly(methyl methacrylate) layer was inserted between the ferroelectric polymer and organic semiconductor layers. The contact resistance was significantly reduced to 55 kΩ cm. By contrast, Fe-OFETs without buffering exhibited a significantly larger contact resistance of 260 kΩ cm. Results showed that such an enhanced charge injection was attributed to the buffering effect at the semiconductor/ferroelectric interface, which narrowed the trap distribution of the organic semiconductor in the contact region. The presented work provided an efficient method of lowering the contact resistance in Fe-OFETs, which is beneficial for the further development of Fe-OFETs.
Synthesis and Characterisation of High Fullerene Content Polymers and Their Use in Organic Photovoltaic Devices
Authors: Clark Sean M. , Campbell Jonathan A. , Lewis David A.
Published: August 2015

Narrow dispersity polymers with a high tethered fullerene content were synthesised by first polymerising poly(chloromethyl styrene) using reversible addition–fragmentation chain transfer (RAFT) polymerisation and subsequently functionalising them with pristine fullerene. The polymers comprised 52 % by weight fullerene, corresponding to approximately one fullerene per monomer in the polymer with a different morphology to poly(3-hexyl thiophene) (P3HT) : phenyl-C61-butyric acid methyl ester (PCBM) systems. Bulk heterojunctions formed from the polymer tethered fullerene (PTF) with P3HT yielded functioning organic photovoltaic devices with power conversion efficiencies ranging from 0.0030 to 0.22 % as the PTF was increased from 1 : 0.8 to 1 : 1.3. Process optimisation resulted in a maximum efficiency of 0.4 %.
Coastal Migration and Homing of Roanoke River Striped Bass
Authors: Callihan Jody L. , Harris Julianne E. , Hightower Joseph E.
Published: August 2015

Anadromy in Roanoke River Striped Bass Morone saxatilis has been documented; however, the specifics of the ocean migration and the degree of homing in this population remain unstudied and would greatly benefit the management of this economically important species. To this end, we telemetered and released 19 large Roanoke River Striped Bass (750–1,146 mm TL) on their spawning grounds during the springs of 2011 and 2012. Data from a large-scale acoustic telemetry array along the U.S. Atlantic coast (480 total receivers, including the Roanoke River) were used to evaluate the seasonal migration and distribution of telemetered fish, their degree of homing and skipped spawning, their migration speeds, and the environmental drivers of migration timing. We found that large Roanoke River Striped Bass (>900 mm TL) rapidly emigrated (~59 km/d) after spawning to distant (>1,000 km) northern ocean waters (New Jersey to Massachusetts), where they spent their summers. They then migrated southward in the fall to overwintering habitats off Virginia and North Carolina and completed their migration circuit the following spring by returning to the Roanoke River to spawn. Our results showed no evidence of straying or skipped spawning, as all migrants successfully returned (homed) to the Roanoke River the next spring to spawn. Cooler ocean water temperatures in 2013 delayed the spring spawning run by nearly 3 weeks relative to a year of average spring temperatures (2012). Our study provides novel information that aids the management of Striped Bass at both small (e.g., setting of fishing seasons in the Roanoke River) and large spatial scales (e.g., stock identification of Roanoke River fish in the mixed-stock ocean fishery) and more broadly highlights the utility of large-scale cooperative telemetry arrays in studying fish migration.

Received February 5, 2015; accepted May 27, 2015
A finiteness theorem for Lagrangian fibrations
Authors: Sawon Justin
Published: August 2015

We consider (holomorphic) Lagrangian fibrations

π
:
X
→

P

n

\pi :X\rightarrow \mathbb {P}^n

that satisfy some natural hypotheses. We prove that there are only finitely many such Lagrangian fibrations up to deformation.
cgmisc: enhanced genome-wide association analyses and visualization
Authors: Kierczak Marcin , Jabłońska Jagoda , Forsberg Simon K. G. , Bianchi Matteo , Tengvall Katarina , Pettersson Mats , Scholz Veronika , Meadows Jennifer R. S. , Jern Patric , Carlborg Örjan , Lindblad-Toh Kerstin
Published: August 2015

Summary: High-throughput genotyping and sequencing technologies facilitate studies of complex genetic traits and provide new research opportunities. The increasing popularity of genome-wide association studies (GWAS) leads to the discovery of new associated loci and a better understanding of the genetic architecture underlying not only diseases, but also other monogenic and complex phenotypes. Several softwares are available for performing GWAS analyses, R environment being one of them.

Results: We present cgmisc, an R package that enables enhanced data analysis and visualization of results from GWAS. The package contains several utilities and modules that complement and enhance the functionality of the existing software. It also provides several tools for advanced visualization of genomic data and utilizes the power of the R language to aid in preparation of publication-quality figures. Some of the package functions are specific for the domestic dog (Canis familiaris) data.

Availability and implementation: The package is operating system-independent and is available from: https://github.com/cgmisc-team/cgmisc

Contact:  marcin.kierczak@imbim.uu.se

Supplementary information:  Supplementary data are available at Bioinformatics online.
Clinical outcome and molecular characterization of pediatric glioblastoma treated with postoperative radiotherapy with concurrent and adjuvant temozolomide: a single institutional study of 66 children
Authors: Jalali Rakesh , Rishi Anupam , Goda Jayant S. , Sridhar Epari , Gurav Mamta , Sharma Pravin , Moiyadi Aliasgar , Shetty Prakash , Gupta Tejpal
Published: August 2015

Background

Glioblastoma (GBM) in children is rare. Pediatric GBM have a distinct molecular profile as compared to adult GBM. There are relatively few studies of pediatric GBMs and no standard of care on adjuvant therapy. We aimed to evaluate the clinical outcome and molecular profile of pediatric GBM.

Methods and Materials

Between 2004 and 2013, 66 consecutive children with histologically proven GBM were identified from our database. The majority of the children underwent maximal safe resection followed by focal radiotherapy with concurrent and adjuvant temozolomide. Immunohistochemical staining was performed for p53, MIB-1 labeling index, MGMT overexpression, and EGFR amplification and isocitrate dehydrogenase (IDH1) R132H point mutation. Survival and impact of possible prognostic factors on outcomes were analyzed.

Result

Median survival was 15 months. The overall survival rate at 1 year was 62%, at 2 years was 30%, and at 3 years was 27%. Patients with thalamic tumors (P < .001), incompletely resected tumors (P < .00001), and tumors with MIB-1 labeling index >25% (P < .002) had poor overall survival rates. p53 was overexpressed in 74% of patients, MGMT promoter methylation was seen in 37% of patients, IDH1 mutation was seen in 4% of patients, and no patients had EGFR amplification. MGMT methylation and p53 overexpression did not impact survival.

Conclusions

Clinical outcome of pediatric GBM is similar to that reported for adult GBM. The frequency of p53 overexpression is higher than in adult GBM, while MGMT methylation, IDH1 mutations and EGFR amplification is lower than in adult GBM. MGMT methylation and p53 expression status do not have any prognostic significance.
Effect of Mixing Time and Speed on Experimental Baking and Dough Testing with a 200 g Pin Mixer
Authors: Brabec Daniel , Rosenau Sam , Shipman Mary
Published: August 2015

Undermixing or overmixing the dough results in varied experimental loaf volumes. Bread preparation requires a trained baker to evaluate dough development and determine the stop points of the mixer. Instrumentation and electronic control of the dough mixer would allow for automatic mixing. This study used a 200 g mixer that provided an output signal during dough mixing to evaluate potential mixing stop points. The effect of varied mixing time on the baked loaf volume was tested by using three flours with protein contents of 10.6, 12.4, and 13.8%. Dough samples were undermixed, mixed to peak, and overmixed. Overmixing by 0.6 min reduced the loaf volume in all flours tested, by 16–50 cm3 at 90 rpm and by 29–68 cm3 at 118 rpm. When the high‐protein flour sample was undermixed, the largest baked loaves were produced, with an average volume of 922 cm3. A second objective studied the similarities and differences between a 200 g mixer and a 35 g mixograph. The same flours were mixed on both units. The mixing peaks for the 200 g mixer were normalized with the 35 g mixograph peaks. When flour and water were used, the mixing times for the 200 g mixer averaged 0.7, 1.2, and 1.6 min shorter than the 35 g mixograph, at 90, 104, and 118 rpm, respectively. Although both the 200 g mixer and the 35 g mixograph system look mechanically similar, they both have unique mechanical motion, speeds, and sample sizes. Their results may show similar trends, but their measured values are usually different. However, when other baking ingredients were included in the 200 g mixer at 90 rpm, the mixing times were within 0.2 min of the 35 g mixograph times for three of four flours.
Physical Activity Is Prospectively Associated With Adolescent Nonalcoholic Fatty Liver Disease
Authors: Anderson Emma L. , Fraser Abigail , Howe Laura D. , Callaway Mark P. , Sattar Naveed , Day Chris , Tilling Kate , Lawlor Debbie A.
Published: August 2015

Objectives:

The aim of the present study was to assess whether objectively measured physical activity at mean ages 12 and 14 years are prospectively associated with ultrasound scan liver fat and stiffness (alanine aminotransferase, aspartate aminotransferase [AST], and γ‐glutamyl transferase [GGT]) assessed at mean age 17.8 years.

Methods:

Participants were from the Avon Longitudinal Study of Parents and Children. Total physical activity (counts per minute) and minutes of moderate to vigorous physical activity (MVPA) were measured using ActiGraph accelerometers at mean ages 12 and 14 years.

Results:

Greater total physical activity and MVPA at ages 12 and 14 years were associated with lower odds of liver fat and lower GGT levels at mean age 17.8 years, such as per 15‐minute increase in daily MVPA at age 12 years, the confounder adjusted odds ratio of liver fat was 0.47 (95% confidence interval [CI] 0.27–0.84). Associations attenuated after additional adjustment for fat mass as a potential confounder (eg, per 15‐minute increase in daily MVPA at age 12 years, the odds ratio of liver fat attenuated to 0.65 [95% CI 0.35–1.21]) or a potential mediator (eg, per 15‐minute increase in daily MVPA at age 12 years the odds ratio of liver fat attenuated to 0.59 [95% CI 0.32–1.09]). Results did not further attenuate after additional adjustment for insulin resistance. There was some evidence that greater total physical activity and MVPA at age 12 years were associated with the higher AST levels.

Conclusions:

Adolescents who were more active in childhood have lower odds of fatty liver and lower GGT levels. These findings are likely to be, at least in part, explained by adiposity.
Endoscopic Treatment of Gastric Outlet Obstruction Secondary to Accidental Acid Ingestion in a Child
Authors: Andrade Mateus , Sawamura Regina , Cupo Palmira , Lopes Del Ciampo Ieda R. , Fernandes Maria I.M.
Published: August 2015

Accidental corrosive ingestion is not rare in pediatric patients in developing countries. We report a case of gastric outlet obstruction after the accidental ingestion of an acidic substance by a child who was successfully treated with endoscopic balloon dilatation.