bluuebunny/crossref_metadata_2025 huggingface dataset:
Cooperation of docosahexaenoic acid and vitamin E in the regulation of UDP‐glucuronosyltransferase mRNA expression
Authors: Caputo Mariella , Eletto Davide , Torino Gaetano , Tecce Mario F.
Published: January 2008

Docosahexaenoic acid (DHA) is a well known chemopreventive nutrient within diet formulations, but it may also exert toxic effects on cultured cells, while this is limited when also another relevant nutrient as vitamin E is present. This effect, beside the involvement of the two nutrients in oxidative processes, likely affects the expression of specific genes. To obtain information on combined activities of DHA and vitamin E on some gene products previously resulted to be in vivo regulated from dietary unsaturated fats, the effect of the two nutrients was evaluated in human cell line HepG2. Independently, DHA and vitamin E resulted to affect only slightly UDP‐glucuronosyltransferase 1A1 (UGT1A1) mRNA expression. Nevertheless, their combination produced a considerable reduction of this mRNA. DHA also downregulated stearoyl‐CoA desaturase (SCD) and sterol regulatory element binding protein (SREBP‐1) expression, while vitamin E did not affect these products. However, their combination abolished the downregulation of SCD but did not affect that of SREBP‐1. Therefore the effect of the two nutrients is related to specific gene regulation processes resulting in a cooperation which might be related to their physiological effects as dietary components. J. Cell. Physiol. 215: 765–770, 2008. © 2008 Wiley‐Liss, Inc.
Platelet‐rich plasma enhances the initial mobilization of circulation‐derived cells for tendon healing
Authors: Kajikawa Yoshiteru , Morihara Toru , Sakamoto Hirotaka , Matsuda Ken‐ichi , Oshima Yasushi , Yoshida Atsuhiko , Nagae Masateru , Arai Yuji , Kawata Mitsuhiro , Kubo Toshikazu
Published: January 2008

Circulation‐derived cells play a crucial role in the healing processes of tissue. In early phases of tendon healing processes, circulation‐derived cells temporarily exist in the wounded area to initiate the healing process and decrease in number with time. We assumed that a delay of time‐dependent decrease in circulation‐derived cells could improve the healing of tendons. In this study, we injected platelet‐rich plasma (PRP) containing various kinds of growth factors into the wounded area of the patellar tendon, and compared the effects on activation of circulation‐derived cells and enhancement of tendon healing with a control group (no PRP injection). To follow the circulation‐derived cells, we used a green fluorescent protein (GFP) chimeric rat expressing GFP in the circulating cells and bone marrow cells. In the PRP group, the numbers of GFP‐positive cells and heat‐shock protein (HSP47; collagen‐specific molecular chaperone)‐positive cells were significantly higher than in the control group at 3 and 7 days after injury. At the same time, the immunoreactivity for types I and III collagen was higher in the PRP group than in the control group at early phase of tendon healing. These findings suggest that locally injected PRP is useful as an activator of circulation‐derived cells for enhancement of the initial tendon healing process. J. Cell. Physiol. 215: 837–845, 2008. © 2008 Wiley‐Liss, Inc.
Radioguided occult lesion localization (ROLL) versus wire‐guided lumpectomy for non‐palpable breast lesions: A randomized prospective evaluation
Authors: Medina‐Franco Heriberto , Abarca‐Pérez Leonardo , García‐Alvarez Miriam N. , Ulloa‐Gómez José L. , Romero‐Trejo Cecilia , Sepúlveda‐Méndez Jesús
Published: January 2008

Background

It is important to optimize the localization technique for non‐palpable breast lesions.

Methods

One hundred consecutive women with non‐palpable breast lesions were randomized to radioguided occult lesion localization (ROLL) or wire localization (WL). For ROLL technique 99mTc‐labeled particles of human serum albumin were injected under breast‐imaging control. Localization of the lesion was done in the operating room with the aid of a gamma‐probe. All lesions were identified in an X‐ray control of the surgical specimen. Categorical variables were analyzed with the Chi‐square method. Significance was considered at P < 0.05.

Results

All procedures were performed on the same day of excision, on ambulatory basis. Both techniques resulted in 100% retrieval of the lesions. Localization time was reduced with ROLL (P < 0.001). Clear margins were achieved in 88.9% ROLLs and 62.5% WLs (P < 0.05) reducing the requirement of re‐excision. There were significant differences in the subjective ease of the procedures in favor of ROLL technique as rated by surgeons and radiologists.

Conclusions

ROLL technique is as effective as WL for excision of non‐palpable breast lesions, reduce localization time and probably the incidence of pathologically involved margins of excision. ROLL appears to improve the learning curve for surgical residents and cosmesis. ROLL is an attractive alternative to WL. J. Surg. Oncol. 2008;97:108–111. © 2008 Wiley‐Liss, Inc.
Serum immunosuppressive acidic protein reflects systemic deterioration of colorectal cancer patient condition
Authors: Toiyama Yuji , Miki Chikao , Inoue Yasuhiro , Okugawa Yoshinaga , Koike Yuki , Watanabe Hideki , Yokoe Takeshi , Hiro Junichirou , Ojima Eiki , Tanaka Kouji , Kusunoki Masato
Published: January 2008

Aims

Immunosuppressive acidic protein (IAP) is a potent biological marker for immunological surveillance in patients with malignant tumors. This study aimed to investigate the significance of serum IAP as an index of disease status, clinicopathological findings and prognosis in colorectal cancer.

Methods

A total of 101 patients with colorectal cancer and 80 normal volunteers were included in this retrospective trial. Preoperative serum IAP was assayed using a commercially available enzyme‐linked immunosorbent assay kit.

Results

The serum IAP level in the patients, which was not associated with clinicopathological features except for tumor size, was significantly higher than that in controls. The serum IAP level was closely correlated with percent body weight loss, serum albumin and cholinesterase, and percentage of circulating lymphocytes reflecting the host's nutritional and immunological conditions. Interestingly, these parameters were not associated with factors reflecting disease progression except for tumor size. The prognosis of patients with higher IAP levels was significantly worse than that of patients with lower IAP levels. Furthermore, an elevated serum IAP level was an independent prognostic marker in all patients.

Conclusion

The preoperative serum IAP level may reflect the general condition of colorectal cancer patients, and thus may predict long‐term survival independently of stage progression. J. Surg. Oncol. 2008;97:404–408. © 2008 Wiley‐Liss, Inc.
Propylene Copolymers with Odd Carbon Number Olefins
Authors: Tincul Ioan , Joubert Dawie , Sanderson Ron
Published: January 2008

Preliminary investigation on propylene copolymers with odd carbon number olefin are reviewed. Additional experimental data presents propylene copolymers with 1‐heptene and 1‐nonene having higher impact strength and lower tensile strength values than copolymers of propylene and 1‐pentene.Thermoanalysis shows that the melting temperatures of the different copolymers decreases with increasing comonomer content. Slight changes were observed between the different propylene/1‐heptene copolymer melting and propylene/1‐pentene while the 1‐nonene copolymers show broadening of the melting curves as the comonomer content increases. It was highlighted that the source of novelty for these polymers is the comonomer type and content.
Morphology Control in Metallocene Polymerization; Organic Supports vs. Non‐aqueous Emulsion Polymerization
Authors: Klapper Markus , Nenov Svetlin , Diesing Till , Müllen Klaus
Published: January 2008

Nano‐sized latex support in metallocene polymerization is known to be able to avoid fuming or leaching and leads to a powder‐like and well‐processable polymer. Focus has been put on the fragmentation behaviour of the particles, a key parameter to morphology control. To study the different behaviour of the new systems as classical inorganic supported metallocenes, e.g. SiO2, a wide range of analytical methods were applied. Fluorescence microscopy, polymerization videomicroscopy, as well as kinetic studies led to a better understanding of the process. The performance of the supports was approved by several phenoxy‐imine type catalysts (“FI‐Catalyst”), which were combined with a tailored latex support. Ultra high molecular weight polyethylene (UHMWPE) was synthesized without any reactor fouling thereby. A different approach towards the metallocene catalyzed olefin polymerization is also presented. Based on emulsion polymerization, it enables very good control over product morphology. The completely hydrophobic system consists of perfluorinated solvent as a continuous phase and a hydrocarbon solvent as a dispersed phase. In contrast to the already existing water based emulsion polymerization of olefins, very high molecular weights are achieved.
Ethylene–Norbornene Copolymerization by Rare‐Earth Metal Complexes and by Carbon Nanotube‐Supported Metallocene Catalysis
Authors: Tritto I. , Boggioni L. , Ravasio A. , Zampa C. , Hitzbleck J. , Okuda J. , Bredeau S. , Dubois P.
Published: January 2008

E–N copolymerization with a number of half‐sandwich rare‐earth metal compounds [M(η5‐C5Me4SiMe2R)(η1‐CH2SiMe3)2(L)] (M = Sc, Y, Lu) has been achieved. Mainly atactic alternating EN copolymers are obtained with all catalytic systems. Interestingly, copolymers arising from [Sc(η5‐C5Me4SiMe2C6F5)(η1‐CH2SiMe3)2(THF)]/[/[Ph3C][B(C6F5)4] possess narrower molar mass distributions than those from [Sc(η5‐C5Me4SiMe3)(η1‐CH2SiMe3)2(THF)]/[Ph3C][B(C6F5)4]. In addition, homogeneous surface coating of multi‐walled carbon nanotubes is accomplished for the first time by in situ E–N copolymerization as catalyzed by rac‐Et(Ind)2ZrCl2/MMAO‐3A anchored onto the carbon nanotube surface. The copolymerization reaction allows for the destructuration of the native nanotube bundles. The relative quantity of EN copolymer can be tuned up as well as the norbornene content in the formed copolymers and accordingly their glass transition temperature. By melt blending with an ethylene‐vinyl‐co‐acetate copolymer (27 wt.‐% vinyl acetate comonomer) matrix, high performance polyolefinic nanocomposites are obtained.
Ethylene Polymerization with Combinations of Early‐ and Late‐Transition Metal Catalysts Immobilized on MgCl2 Supports
Authors: Chadwick John C. , Huang Rubin , Kukalyekar Nileshkumar , Rastogi Sanjay
Published: January 2008

Immobilization of combinations of early‐ and late‐transition metal catalysts on MgCl2 supports has led to significant increases in catalyst activity when a nickel diimine is incorporated into a Fe‐, Cr‐ or Ti‐based catalyst system, and to the formation of intimately mixed, bimodal blends of high‐ and low‐molecular weight polyethylene via coimmobilization of Cr and Fe catalysts.
Ethylene Polymerization over Supported Titanium‐Magnesium Catalysts: Heterogeneity of Active Centers and Effect of Catalyst Composition on the Molecular Mass Distribution of Polymer
Authors: Zakharov Vladimir , Matsko Mikhail , Echevskaya Ludmila , Mikenas Tatiana
Published: January 2008

New experimental approach was used for analysis of molecular weight distribution (MWD) of polymers produced over titanium‐magnesium catalysts (TMC). Polymers were fractionated on to fractions with narrow MWD (polydispersity (PD) values Mw/Mn ≤ 2). Then some of these fractions were combined to get the minimal quantity of fractions with PD values close to 2 (Flory components). It was found that three fractions corresponding to three groups of active centers are sufficient for proper fitting experimental MWD curve for PE obtained over TMC with different Ti content and with different hydrogen concentration in polymerization.
Neurological presentation of Wilson's disease in a patient after liver transplantation
Authors: Litwin Tomasz , Gromadzka Grazyna , Członkowska Anna
Published: January 2008

We report of a 32‐year‐old man who showed dystonic symptoms within few days after liver transplantation (LT). The clinical, biochemical, and, finally, genetic evaluation confirmed Wilson's disease diagnosis in this patient. We suspect that extrapyramidal signs in this case could be a result of acute brain injury because of the massive copper release from liver to the circulation just before and during LT. © 2008 Movement Disorder Society
The effectiveness of exercise interventions for people with Parkinson's disease: A systematic review and meta‐analysis
Authors: Goodwin Victoria A. , Richards Suzanne H. , Taylor Rod S. , Taylor Adrian H. , Campbell John L.
Published: January 2008

Parkinson's disease (PD) is a neurodegenerative disorder affecting the physical, psychological, social, and functional status of individuals. Exercise programs may be an effective strategy to delay or reverse functional decline for people with PD and a large body of empirical evidence has emerged in recent years. The objective is to systematically review randomized controlled trials (RCTs) reporting on the effectiveness of exercise interventions on outcomes (physical, psychological or social functioning, or quality of life) for people with PD. RCTs meeting the inclusion criteria were identified by systematic searching of electronic databases. Key data were extracted by two independent researchers. A mixed methods approach was undertaken using narrative, vote counting, and random effects meta‐analysis methods. Fourteen RCTs were included and the methodological quality of most studies was moderate. Evidence supported exercise as being beneficial with regards to physical functioning, health‐related quality of life, strength, balance and gait speed for people with PD. There was insufficient evidence support or refute the value of exercise in reducing falls or depression. This review found evidence of the potential benefits of exercise for people with PD, although further good quality research is needed. Questions remain around the optimal content of exercise interventions (dosing, component exercises) at different stages of the disease. © 2008 Movement Disorder Society
Psychological distress and GI symptoms are related to severity of bloating in women with irritable bowel syndrome
Authors: Park Hyo Jung , Jarrett Monica , Cain Kevin , Heitkemper Margaret
Published: January 2008

Bloating is a frequent complaint of women with irritable bowel syndrome (IBS). We compared retrospective and daily diary gastrointestinal and psychological distress symptoms in 183 women ages 18–48 in three IBS subgroups: Minimal‐Bloating, Mild‐Bloating, Moderate‐Severe‐Bloating. More women with moderate to severe levels of bloating reported a history of hard stools, straining to have a stool, a history of depressive disorders, and more severe daily symptoms of depression and anxiety as compared to women with minimal or mild bloating symptoms. Appraising the level of symptom severity and psychological distress is vital to the selection of appropriate treatment options. © 2008 Wiley Periodicals, Inc. Res Nurs Health 31:98–107, 2008
Focus groups as an intervention for low‐income African American smokers to promote participation in subsequent intervention studies
Authors: Webb Monica S.
Published: January 2008

African Americans are often underrepresented in smoking cessation research. Focus groups were examined as an intervention to increase readiness to quit smoking, the processes of change, and the odds of randomized clinical trial (RCT) participation of non‐treatment‐seeking, low‐income African American smokers. Ten focus groups were conducted. Smokers completed baseline and/or post‐group assessments of readiness to quit, the processes of change, and focus group quality. Significant increases were discerned in readiness to quit smoking and the processes of change. Seventy‐six percent of participants enrolled in a self‐help RCT, which was associated with readiness to quit smoking and plans to set a quit date. One‐session focus groups among low‐income African American smokers appear to facilitate cognitive changes and participation in RCTs. © 2008 Wiley Periodicals, Inc. Res Nurs Health 31:141–151, 2008
Which of the Big Five factors are in need of situational specification?
Authors: De Raad Boele , Sullot Esther , Barelds Dick P. H.
Published: January 2008

With the availability of a personality relevant situation taxonomy (Ten Berge & De Raad, 2002), a burning question ahead is whether systematic inclusion of situation references in personality questionnaires does improve their descriptive and predictive capacities. In this paper, the reliability question was addressed, and we investigated for which factors of the Big Five the interjudge‐agreement would increase upon adding situational information. In this study we excluded the fifth factor, Intellectual Autonomy. Two studies were performed, involving a first test in Study 1, and a replication with three tests through varying sets of items in Study 2. In Study 1, trait descriptive adjectives representing four factors were administered twice (N = 182), one time without and one time with situational information. In Study 2 (N = 152), we varied both the trait‐adjectives and the situational trait‐sentences from set to set. All four tests indicated that the interjudge‐agreement for Extraversion generally decreased upon adding situation information, for Agreeableness and Conscientiousness it did not essentially change, and the interjudge‐agreement for Emotional Stability substantially increased. Some explanations and implications are discussed. Copyright © 2008 John Wiley & Sons, Ltd.
Advances in inherent safety guidance
Authors: Moore David A. , Hazzan Mike , Rose Marty , Heller David , Hendershot Dennis C. , Dowell Arthur M.
Published: January 2008

The classic reference from CCPS “Inherently Safer Chemical Processes, A Life Cycle Approach”, 1st edition, 1996, was updated in 2006–2007. The goal of this book is to influence the future state of chemical process evolution by illustrating and emphasizing the merits of integrating process research, development, and design into a comprehensive process that balances safety, capital, and environmental concerns throughout the life cycle of the process. The authors hope that this book will influence the next generation of engineers and chemists as well as current practitioners and managers in the field of chemical processing.

Lessons learned since the first edition of the CCPS® inherent safety concept book in 1996, combined with the fact that inherently safer design (ISD) is becoming more widely accepted prompted CCPS® to update the book. Also, since 1996, several jurisdictions have mandated consideration of ISD for certain facilities, and such requirements have been proposed at the Federal level in the United States. In particular, there is a need for more guidance, especially in practical, step‐wise approaches to conduct inherently safer studies. This new edition builds on the first edition with the same philosophy but clarifies the concept with recent research and thoughts of practitioners, added examples, added more industry methods, security issues, and a discussion on regulatory issues. A key feature of the new book is the clarification of the meaning of ISD by setting the 1st and 2nd orders of ISD. This is distinguished from layers of protection and other traditional process safety concepts.

Numerous added examples and checklists make this a very practical guide and a good edition to the library of anyone involved in process risk management. © 2008 American Institute of Chemical Engineers Process Saf Prog, 2008
Effect of application timing and method on efficacy and phytotoxicity of 1,3‐D, chloropicrin and metam‐sodium combinations in squash plasticulture
Authors: Desaeger Johan A , Seebold Kenneth W , Csinos Alex S
Published: January 2008

BACKGROUND: Metam‐sodium, 1,3‐dichloropropene (1,3‐D) and chloropicrin are widely used soil fumigants. Combined application of metam‐sodium and 1,3‐D + chloropicrin is intended to improve efficacy and broaden spectrum of control, but little is known about the effect on crop safety. This study aimed to evaluate the effects of application timing of fumigant combinations on soilborne pest and disease control (nematodes, soil fungi and weeds) and growth of squash. Two separate tests with chisel‐injected and drip‐applied fumigant combinations and plant‐back times ranging from 1 to 4 weeks were conducted in Tifton, GA, USA, in spring and fall 2002.

RESULTS: Fumigant combinations using 1,3‐D, chloropicrin and metam‐sodium were as effective as methyl bromide in controlling Meloidogyne incognita (Kofoid & White) Chitwood, Pythium irregulare Buis., Rhizoctonia solani Kühn and Cyperus esculentus L. Chisel‐applied combinations were more effective in terms of root‐knot nematode control than drip‐applied combinations. Root‐knot nematode reduced squash yields by up to 60%. Phytotoxicity problems and lower yields were observed during spring, especially following 1,3‐D + chloropicrin and when plant‐back periods were shorter.

CONCLUSION: The main problem with fumigant alternatives to methyl bromide may not be reduced efficacy but, in particular for 1,3‐D products, loss of flexibility in terms of longer plant‐back periods. Copyright © 2008 Society of Chemical Industry
The influence of the extensional viscosity of very low concentrations of high molecular mass water‐soluble polymers on atomisation and droplet impact
Authors: Williams Peter A , English Robert J , Blanchard Rowan L , Rose Simon A , Lyons Lynn , Whitehead Mark
Published: January 2008

BACKGROUND: Water‐soluble polymers are increasingly added to herbicide and pesticide formulations at very low concentrations (100–1000 mg L−1) in order to control the spray characteristics, notably to reduce spray drift and influence droplet bounce. The incorporation of polymeric adjuvants improves the efficacy of the spray solutions, thus enabling crop growers to maximise the performance of agrochemical sprays at lower dose rates of active ingredient. It is important to establish a fundamental understanding of how polymers influence the processes involved in droplet deposition.

RESULTS: The shear and extensional viscosities of a series of high molecular mass (Mw) poly(acrylamides) (Mw ∼ 106–107) have been determined at very low concentrations (100–1000 mg L−1). The polymer solutions demonstrated typical shear thinning characteristics under shear, and strain hardening behaviour under extension above a critical strain rate. The presence of the polymers was shown to increase the size of droplets produced in atomisation using an agricultural spray nozzle, as measured by laser diffraction. This was attributed to the increase in the extensional viscosity at the strain rates generated under pressure in the spray nozzle and was a function of both polymer concentration and Mw. In addition, the presence of polymer was found to have a significant influence on droplet bounce.

CONCLUSIONS: The presence of very low concentrations of high molecular mass poly(acrylamides) significantly influences the size of droplets formed on atomisation and subsequent bounce characteristics. Large extensional viscosities generated above a critical strain rate are responsible for both processes. Copyright © 2008 Society of Chemical Industry
Editorial: phys. stat. sol. (b) 245/1
Authors: Stutzmann Martin
Published: January 2008

How do you find the scientific information and the manuscript reference you need? The answer to this basic but very important question for every active scientist has changed significantly over the last 30 years. When I was a Ph.D. student or a young postdoc, I would venture regularly to a strange and quiet place called a “library”, where all important journals in my field could be easily identified already from the amount of the shelve space they filled. To find a specific reference and to preserve it for future use was limited by the physical exercise to carry a stack of heavy volumes to the copy machine and to press a “copy” button for each page I really wanted to keep. On the way, sometimes I actually found another interesting paper just by browsing through the latest issue of Journal X, and I copied this one, too. And in most cases, I even read what I copied.

Today, things are much better! All relevant information is available online in electronic form, so I do not have to leave my office anymore to find out what's new. The impact factors of journals and the h‐factors of authors help me to distinguish good from bad, or at least that is the hope. Whenever I search for a specific topic, anyhow I will get more hits than I can digest in a realistic time. Fortunately, printers by now are so fast and powerful that I can transfer the rest to a printout which I will, most likely, never use again in the foreseeable future.

But seriously, although the way to make use of and to deal with scientific information has changed drastically in the last couple of decades, the basic needs of active scientists for reliable, up‐to‐date, and easily accessible information exchange with their international colleagues worldwide has basically remained the same. We at physica status solidi, therefore, for more than 45 years have been and are dedicated to provide exactly that service to our authors and readers, whether they make use of the pss hardcopies in the library or whether they browse the online files of physica status solidi. Last year, more than 2500 articles have been published after strict peer review and careful editing, which makes physica status solidi (nomen est omen) the second largest journal series in solid state physics. The journal has more than doubled in volume since the year 2000, but the Impact Factor also has increased by a factor of two since 1995, showing that we did not trade in quantity for quality. And, last but not least, the visibility of the journal series as measured by the number of full text downloads has increased by a similar factor of two in the last 24 months alone.

In October 2007, more than 40000 full text downloads of physica status solidi articles have been registered by the Wiley Interscience data base. Unfortunately, we have no idea how many of these articles have actually been read …

In the name of the entire pss‐team, I thank all of you for your continued support of and interest in physica status solidi and wish you a successful year 2008!
Quantum electron transport modeling in uniaxially strained silicon channel of double‐gate MOSFETs
Authors: Fitriawan Helmy , Ogawa Matsuto , Souma Satofumi , Miyoshi Tanroku
Published: January 2008

This paper reports the calculation of quantum electron transport in double‐gate metal oxide semiconductor field effects transistors (MOSFETs) with uniaxially strained silicon channel. The calculation is formulated based on multiband non‐equilibrium Green's function (NEGF) method coupled self‐consistently with the Poisson equation. The empirical sp3s * tight binding approximation (TBA) model with nearest neighbor coupling is employed to obtain more realistic band structure in the formulation. We compare the carrier transport characteristics of simulated MOSFETs with strained channel to those of without strain. The simulation results show that the presence of uniaxially strain induce the current enhancement in the devices. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrical modelling for carbon nanotubes
Authors: Nakamura H. , Katayama Y.
Published: January 2008

Based on the NEGF and tight‐binding approaches, the bias‐induced energy of the metallic CNT is accounted for by the capacitance or inductance in the proposed equivalent circuit model, from which we get an excellent agreement with the semi‐classical treatments. The kinetic energy of the electrons in the subband for a FETCNT is modelled as an additional quantum capacitance, which suggests a modified circuit model. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Charge transport in oligophenylenvinylene molecules
Authors: Schuster S. , Scarpa G. , Latessa L. , Lugli P.
Published: January 2008

We have performed a theoretical analysis of current transport in oligophenylenvinylene (OPV) molecules based on the density functional tight‐binding (DFTB) method, extended to the non‐equilibrium Green's functions (NEGF) for the self‐ consistent computation of charge density and electronic transport. The results illustrate the importance of molecular features such as thiols bridges and functionalization groups in determining the transport characteristics of single molecules. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hot electron effects in ultra‐short gate length InAs/InAlAs HEMTs
Authors: Ayubi‐Moak J. S. , Akis R. , Saraniti M. , Ferry D. K. , Goodnick S. M.
Published: January 2008

High field transport in short channel (sub‐100 nm gate length), InAs/InAlAs pseudomorphic high‐electron mobility transistors (pHEMTs) has been studied using a full‐band Cellular Monte Carlo (CMC) simulator. Reasonable agreement is obtained between simulated devices and recent experimental results in terms of the current, voltage and cutoff frequency. Both 70 nm and 35 nm gate length devices have been simulated in this work. Sustained high carrier energies near the drain electrode are observed and attributed to the long scatter‐ ing times from both X and L valleys back to the Γ valley in InAs. Strong overshoot effects are also apparent in the velocity, although the corresponding increase in cutoff frequency is not as pronounced as expected from simple scaling of the gate length. The relation of this velocity behaviour to the experimental and simulated frequency response is discussed, as well as the limits of performance in this technology as gate lengths are scaled further. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Energy relaxation time of hot carriers photoexcited in InGaN
Authors: Ushiyama T. , Toizumi T. , Nakazato Y. , Tackeuchi A.
Published: January 2008

The energy relaxation time of hot carriers photoexcited in bulk InGaN is measured. The time‐resolved pump and probe transmission measurements with subpicosecond time resolution show that the hot‐carrier relaxation time is 0.92 ps at 15 K. The hot‐carrier relaxation time becomes significantly shorter at higher temperatures. At temperatures higher than 150 K, there are no meaningful differences between rise times. This strong temperature dependence indicates that electron‐phonon scattering dominates the carrier relaxation process. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Negative spin polarization in AlGaAs photoluminescence
Authors: Gilinsky A. M. , Winter A. , Mejía‐García C. , Pascher H. , Zhuravlev K. S. , Efanov A. V. , Kozhemyakina E. V.
Published: January 2008

Optical orientation of carrier spins has been studied in pure direct‐gap AlxGa1–xAs alloys (x up to 15%). It is shown that optical excitation with circularly‐polarized light with quanta energy in a narrow range (less than 1.6 meV) just above the free exciton transition results in the appearance of negative circular polarization of near‐band edge photoluminescence (PL), which indicates a reversal of the spin orientation direction. The PL polarization degree becomes negative on all the excitonic transitions in the spectrum, free as well as bound. Carrier spin kinetics observed using the Hanle technique shows insignificant modification under the resonant excitation. The resonant switching of PL polarization seen in the excitation spectrum points to a change in the dominating carrier generation channel from heavy‐hole to light‐hole. The change is attributed to the influence of mechanical stress between the ternary epitaxial film and the substrate of GaAs. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonlinear electron transport properties and rectification effects in InAs/AlGaSb ballistic devices
Authors: Koyama M. , Inoue T. , Amano N. , Maemoto T. , Sasa S. , Inoue M.
Published: January 2008

The nonlinear electron transport properties and rectification effects in InAs/AlGaSb ballistic devices are reported. We fabricated InAs/AlGaSb three‐terminal ballistic junction devices composed of three quantum wires, and characterised electron transport properties with scanning the voltage on the left branch while keeping the voltage on the right constant at 77 K and 300 K. In these structures, we observed clear nonlinearity in the output voltage measured at the central branch. The nonlinear characteristics agreed well with a theoretical prediction. When the left branch is biased to a finite voltage V and the right to a voltage of –V (push‐pull fashion), negative voltages appeared at the central branch regardless of the polarity of V. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preface: phys. stat. sol. (c) 5/1
Authors: Tarucha Seigo , Furuya Kazuhito , Hirakawa Kaz , Yamaguchi Masahito , Oiwa Akira
Published: January 2008

This issue contains invited and contributed papers of the 15th International Conference on Nonequilibrium Carrier Dynamics in Semiconductors (HCIS15) held 23–27 July 2007 at Hongo Campus, University of Tokyo, Tokyo, Japan.

The conference featured 11 invited and 55 con‐tributed talks as well as 80 posters, and an international attendance of more than 160 scientists. Following the tradition of the conference, HCIS15 provided an international forum on the latest progress in the field of physics and applications of nonequilibrium carrier dynamics in bulk semiconductors, nanostructures, and structures of molecular scales. Interesting contributions were made on transport in novel nanostructures and nanodevices, intersubband transitions and terahertz phenomena, ultrafast spectroscopy, and spintronics, which clearly indicates the importance of these topics for the next generation devices.

On behalf of the organizers of HCIS15, we thank all the participants who made the conference a successful and pleasant experience. We sincerely appreciate support from the Japan Society of Applied Physics and Electronics Society, IEICE. Generous donations from foundations and companies are gratefully acknowledged. We are also indebted to Michihisa Yamamoto, Kenji Shibata, Sayoko Muta, Mari Ikushima, and Mika Tsukamoto for their invaluable contribution to the conference organization. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Combination of high‐resolution RBS and angle‐resolved XPS: accurate depth profiling of chemical states
Authors: Kimura Kenji , Nakajima Kaoru , Zhao Ming , Nohira Hiroshi , Hattori Takeo , Kobata Masaaki , Ikenaga Eiji , Kim Jung Jin , Kobayashi Keisuke , Conard Thierry , Vandervorst Wilfried
Published: January 2008

A new method for the combination analysis of high‐resolution Rutherford backscattering spectroscopy (HRBS) and angle‐resolved X‐ray photoelectron spectroscopy (AR‐XPS) is proposed for accurate depth profiling of chemical states. In this method, attenuation lengths (ALs) for the photoelectrons are first determined so that the AR‐XPS result is consistent with the HRBS result. Depth profiling of the chemical states are then performed in the AR‐XPS analysis using the composition‐depth profiles obtained by HRBS as constrained conditions. This method is successfully applied to Hf‐based gate stack structures demonstrating its feasibility. Copyright © 2008 John Wiley & Sons, Ltd.
Genetic relationships among populations of the Argentine ant Linepithema humile introduced into Japan
Authors: Hirata Masanori , Hasegawa Osamu , Toita Takahiro , Higashi Seigo
Published: January 2008

Since some colonies of Argentine ant Linepithema humile were discovered in Japan in 1993, populations of this invasive alien ant species have been expanding their distribution. To resolve the number of invasions and the genetic structure in the early stages of introduction, we inferred the genetic structure and relationships among colonies from eight localities, from analyses of eight nuclear microsatellite DNA markers. FST analysis, principal component analysis and assignment test showed that at least three highly genetically differentiated groups of Argentine ants are present in Japan. Populations from Hiroshima Bay were grouped together (Hiroshima, Hatsukaichi, Otake, Iwakuni Central and Iwakuni Kuroiso), while those from Kobe and Yanai were both genetically distant from each other and from the Hiroshima Bay group. Hatsukaichi and Kobe are international seaports, suggesting that the by‐ship invasion occurred at least twice. The invasion route of the Yanai population is unknown at this moment. The Aichi population was genetically distant from that of the Hiroshima Bay group by the difference in allele frequencies, and it was plausible that the Aichi population was introduced from the Hiroshima Bay group by human‐mediated jump dispersal.
Patterns of Azteca ants’ defence of Cecropia trees in a tropical rainforest: support for optimal defence theory
Authors: Gianoli Ernesto , Sendoya Sebastián , Vargas Fernando , Mejía Paula , Jaffé Rodolfo , Rodríguez Mayanín , Gutiérrez Adrián
Published: January 2008

Optimal defence theory (ODT) predicts that, whereas high risk of herbivory should select for high constitutive levels of defence, induced defences should be more advantageous in environments with a low probability of herbivory. In the present field study, conducted on the Azteca–Cecropia ant–plant system in a Neotropical rainforest, we evaluated whether the constitutive and induced ant defence of leaves are directly and inversely related to an estimate of herbivory risk, respectively. To assess the constitutive level of Azteca defence in Cecropia obtusifolia trees, we recorded the number of ants patrolling undamaged leaves. To evaluate the induced level of Azteca defence, the same leaves were subjected to simulated herbivory by punching circular holes in them. We recorded the maximum number of ants patrolling the damaged leaves from 2 to 15 min after damage. Past herbivory (% defoliation of old leaves) was assumed to indicate a risk of herbivory. Regression analyses showed that, whereas the constitutive level of ant patrolling was positively associated with the magnitude of herbivory on old leaves, there was a negative association between the magnitude of induced ant defence and past herbivory. These preliminary results lend support to ODT.
Magnetometric Studies of Catalyst Refuses in Nanocarbon Materials
Authors: Ovsienko Irina V , Matzuy LyudmilaYu , Zakharenko Nykolai I , Babich Nykolai G , Len Tetyana A , Prylutskyy Yuriy I , Hui David , Strzhemechny Yuri M , Eklund Peter C
Published: January 2008

It is shown that magnetometry can be employed as an effective tool to control the content of a ferromagnetic constituent in nanocarbon materials. We propose a thermochemical treatment protocol to achieve extensive cleaning of the source nanocarbon materials from ferromagnetic refuses.
Ultrasound lung comets for the differential diagnosis of acute cardiogenic dyspnoea: A comparison with natriuretic peptides☆
Authors: Gargani L. , Frassi F. , Soldati G. , Tesorio P. , Gheorghiade M. , Picano E.
Published: January 2008

Background:

Acute dyspnoea as a presenting symptom is a frequent diagnostic challenge for physicians. The main differential diagnosis is between dyspnoea of cardiac and non‐cardiac origin. Natriuretic peptides have been shown to be useful in this setting. Ultrasound lung comets (ULCs) are a simple, echographic method which can be used to assess pulmonary congestion.

Aim:

To evaluate the accuracy of ULCs for predicting dyspnoea of cardiac origin compared to natriuretic peptides.

Methods:

We evaluated 149 patients admitted with acute dyspnoea. Chest sonography and NT‐proBNP assessments were performed a maximum of 4 h apart and independently analyzed. ULCs were evaluated via cardiac probes placed on the anterior and lateral chest. Two independent physicians, blinded to ULCs and NT‐proBNP findings, reviewed all the medical records to establish the aetiologic diagnosis of dyspnoea.

Results:

Cardiogenic dyspnoea was confirmed in 122 patients and ruled‐out in 27 patients. The number of ULCs was significantly correlated to NT‐proBNP values (r=.69, p<.0001). Receiver operating characteristic analysis, showed an area under the curve of .893 for ULCs and .978 (p=.001) for NT‐proBNP, in predicting the cardiac origin of dyspnoea.

Conclusions:

In patients admitted with acute dyspnoea, pulmonary congestion, sonographically imaged as ULCs, is significantly correlated to NT‐proBNP values. The accuracy of ULCs in predicting the cardiac origin of dyspnoea is high.
Combining the ventilatory response to exercise and peak oxygen consumption is no better than peak oxygen consumption alone in predicting mortality in chronic heart failure
Authors: Ingle Lee , Witte Klaus K. , Cleland John G.F. , Clark Andrew L.
Published: January 2008

Background:

A low peak oxygen uptake (pVO2) and steep VE/VCO2 slope are independently associated with a worse prognosis in patients with chronic heart failure (CHF). We wished to confirm whether combining these variables as a ratio would lead to a more accurate predictor of prognosis than using either alone.

Methods:

388 CHF patients completed a treadmill‐based cardiopulmonary exercise test (CPET) to volitional exhaustion using a modified Bruce protocol.

Results:

212 CHF patients completed the CPET with a peak RER ≥1.0. Of these, 48 patients died and one was transplanted during follow‐up. In surviving patients, the median follow‐up period was 42 months (IQR 34–49 months). The ratio VE/VCO2 slope/pVO2 was calculated for each individual and its ability to predict outcome compared with other variables. The Cox multivariable survival analysis showed that pVO2 was the strongest independent predictor of mortality in CHF patients.

Conclusion:

Our study shows that the composite variable VE/VCO2 slope/pVO2 is a less effective prognosticator than pVO2 alone in patients with CHF.
A randomised trial of a pre‐synaptic stimulator of DA2‐dopaminergic and α2‐adrenergic receptors on morbidity and mortality in patients with heart failure
Authors: Torp‐Pedersen Christian , Køber Lars , Carlsen Jan E. , Akkan Dilek , Bruun Niels E. , Dacoronias Dimitri , Dickstein Kenneth , Haghfelt Torben , Öhlin Hans , McMurray John JV
Published: January 2008

Background:

By pre‐synaptic stimulation of DA2‐dopaminergic and α2‐adrenergic receptors, nolomirole inhibits norepinephrine secretion from sympathetic nerve endings. We performed a clinical study with nolomirole in patients with heart failure (HF).

Methods:

The study was designed as a multicentre, double blind, parallel group trial of 5 mg b.i.d. of nolomirole (n=501) versus placebo (n=499) in patients with severe left ventricular systolic dysfunction, recently in New York Heart Association (NYHA) class III/IV. The primary endpoint was time to all cause death or hospitalisation for HF, whichever came first. The study was event driven and required 420 primary events. The study was completed as scheduled.

Results:

Mean age of patients was 70 years, and 73% were male. Heart rate and blood pressure were not different in the two treatment groups. There were no changes in blood pressure. There were 233 primary events in the nolomirole group versus 208 in the placebo group (p=0.1). There were 142/145 deaths and 369/374 all cause hospitalisations in the nolomirole/placebo groups. There were no differences in walking distance, quality of life or NYHA class.

Conclusion:

A dose of 5 mg b.i.d. of nolomirole was not beneficial (or harmful) in patients with heart failure.
B‐type natriuretic peptide levels in patients with functionally univentricular hearts after total cavopulmonary connection
Authors: Koch Andreas M.E. , Zink Stefan , Singer Helmut , Dittrich Sven
Published: January 2008

Aims:

To assess plasma B‐type natriuretic peptide (BNP) levels in patients with univentricular hearts late after volume unloading by total cavopulmonary connection (TCPC).

Methods:

Plasma BNP was measured by sandwich immunoassay in 67 patients after a modified Fontan procedure. BNP levels were compared with age and sex‐specific normal values, clinical and echocardiographic data, and results of exercise testing.

Results:

BNP had a wide range of 5–290 pg/ml, but was normal in 81% of patients, and median BNP was only 13pg/ml. There was no difference between males and females, between patients with left or right ventricular morphology, and no correlation was found between BNP and age, post‐operative follow‐up period, maximum exercise capability, peak oxygen uptake, or blood oxygen saturation. New York Heart Association class I patients had lower BNP than class II patients (p=0.04). Plasma BNP concentration was positively correlated to the number of specific sequelae (r=0.59, p<0.001), and to severity of atrioventricular regurgitation (r=0.38, p=0.002). 5/13 patients with elevated BNP died during follow‐up.

Conclusion:

BNP plasma concentration was normal in the majority of patients up to 15 years after TCPC. Elevated and increasing BNP levels were associated with increased morbidity and late mortality.
Clinical trials update from the American Heart Association 2007: CORONA, RethinQ, MASCOT, AF‐CHF, HART, MASTER, POISE and stem cell therapy
Authors: Cleland John G.F. , Coletta Alison P. , Abdellah Ahmed Tageldien , Cullington Damien , Clark Andrew L. , Rigby Alan S.
Published: January 2008

This article provides information and a commentary on trials relevant to the pathophysiology, prevention and treatment of heart failure, presented at the American Heart Association 2007. These should be considered as preliminary data, as analyses may change in the final publication.

Rosuvastatin did not reduce mortality compared to placebo in patients with heart failure and left ventricular systolic dysfunction due to ischaemic heart disease in the CORONA study. Results of RethinQ provide equivocal evidence of benefit from CRT in patients with heart failure, echocardiographic dyssynchrony and QRS interval <130 ms. In the MASCOT study, the addition of atrial overdrive pacing did not reduce the incidence of permanent atrial fibrillation in patients receiving CRT. The AF‐CHF study failed to show a benefit of rhythm control over rate control in patients with heart failure and atrial fibrillation. Self‐management skills training and education had no benefit on the combined outcome of death or heart failure hospitalisation, compared with education alone in heart failure patients in the HART study. Microvolt T‐wave alternans testing failed to identify patients at increased risk of life‐threatening ventricular arrhythmias in the MASTER study. POISE suggests that initiating metoprolol therapy shortly prior to non‐cardiac surgery increases the risk of hypotension, stroke and death, despite reducing the risk of myocardial infarction. Three trials of stem cell therapy in post‐MI patients gave conflicting results.