bluuebunny/crossref_metadata_2025 huggingface dataset:
Unsupervised host behavior classification from connection patterns
Authors: Dewaele Guillaume , Himura Yosuke , Borgnat Pierre , Fukuda Kensuke , Abry Patrice , Michel Olivier , Fontugne Romain , Cho Kenjiro , Esaki Hiroshi
Published: September 2010

A novel host behavior classification approach is proposed as a preliminary step toward traffic classification and anomaly detection in network communication. Although many attempts described in the literature were devoted to flow or application classifications, these approaches are not always adaptable to the operational constraints of traffic monitoring (expected to work even without packet payload, without bidirectionality, on high‐speed networks or from flow reports only, etc.). Instead, the classification proposed here relies on the leading idea that traffic is relevantly analyzed in terms of host typical behaviors: typical connection patterns of both legitimate applications (data sharing, downloading, etc.) and anomalous (eventually aggressive) behaviors are obtained by profiling traffic at the host level using unsupervised statistical classification. Classification at the host level is not reducible to flow or application classification, and neither is the contrary: they are different operations which might have complementary roles in network management. The proposed host classification is based on a nine‐dimensional feature space evaluating host Internet connectivity, dispersion and exchanged traffic content. A minimum spanning tree (MST) clustering technique is developed that does not require any supervised learning step to produce a set of statistically established typical host behaviors. Not relying on a priori defined classes of known behaviors enables the procedure to discover new host behaviors, that potentially were never observed before. This procedure is applied to traffic collected over the entire year of 2008 on a transpacific (Japan/USA) link. A cross‐validation of this unsupervised classification against a classical port‐based inspection and a state‐of‐the‐art method provides assessment of the meaningfulness and the relevance of the obtained classes for host behaviors. Copyright © 2010 John Wiley & Sons, Ltd.
Experiences of VoIP traffic monitoring in a commercial ISP
Authors: Birke Robert , Mellia Marco , Petracca Michele , Rossi Dario
Published: September 2010

VoIP (Voice over IP) has widely been addressed as the technology that will change the telecommunication model, opening the path for convergence. Yet this revolution is far from being complete, since, as of today the majority of telephone calls are still originated by circuit‐oriented networks. In this paper we present our experience in the real‐time monitoring of VoIP calls from a commercial operational network. We discuss and present a methodology and a large dataset of measurements, collected from the FastWeb backbone, which is one of the first worldwide Telecom operators to offer VoIP and high‐speed data access to the end‐user. Traffic characterization focuses on several layers, concentrating on both end‐user and ISP perspectives. In particular, we highlight that, among loss, delay and jitter, only the first index may affect VoIP call quality. Overall, results show that the technology is mature enough to make the final step, allowing the integration of data and real‐time services over the Internet. Copyright © 2010 John Wiley & Sons, Ltd.
Pharmakologie von NO und der Nitrate. Ein Autoabgas macht Karriere
Authors: Li Huige , Förstermann Ulrich
Published: September 2010

Nitrovasodilatatoren haben seit langem (und immer noch) einen signifikanten Stellenwert bei der Behandlung der koronaren Herzkrankheit. Sie werden zur Kupierung pectanginöser Anfälle (z.B. Glyceroltrinitrat) oder für die Intervallbehandlung der Angina pectoris (z.B. Pentaerythrityltetranitrat) eingesetzt. Nitroprussid‐Natrium findet kaum noch klinische Anwendung (etwa zur Steuerung einer kontrollierten Hypotension in der Chirurgie). Dank der selektiven Senkung des pulmonalarteriellen Drucks und der schnellen Verbesserung des Gasaustausches ist inhaliertes NO als Akutmaßnahme zur Behandlung schwerer akuter pulmonaler Hypertonie und/oder schwerer arterieller Hypoxämie geeignet (v.a. bei Kindern). Neuere Arneistoffentwicklungen finden sich in Form NO‐freisetzender Pharmaka mit anderem Hauptwirkmechanismus. Diese Entwicklung ist am weitesten fortgeschritten bei NO‐freisetzenden nicht‐steroidalen Antiphlogistika wie z.B. Naproxcinod. Bei ähnlicher Wirksamkeit wie Naproxen verursachte es tendenziell weniger unerwünschte gastrointestinale Wirkungen und hat nicht die blutdrucksteigernde Wirkung der Muttersubstanz.
Medizinische Chemie der Nitrate und PDE5‐Hemmer. Wie zwei Zufallsentdeckungen den Markt eroberten
Authors: Roegler Carolin , Lehmann Jochen
Published: September 2010

Sowohl organische Nitrate als auch Hemmstoffe der Phosphodiesterase 5 (PDE5) sind vasodilatatorische Substanzen. Während die zunächst als Sprengstoffe konzipierten organischen Nitrate als Antianginosa hauptsächlich zur Behandlung der koronaren Herzkrankheit (KHK) genutzt werden, finden die ursprünglich zur Angina‐pectoris‐Therapie entwickelten PDE5‐Hemmer Anwendung als Therapeutika der erektilen Dysfunktion sowie der pulmonalen Hypertonie.
Therapie der koronaren Herzerkrankung mit NO‐Donatoren. Nach wie vor eine wichtige Option
Authors: Münzel Thomas , Schulz Eberhard
Published: September 2010

Nitrate stellen nach wie vor eine wichtige Therapiesäule der koronaren Herzerkrankung dar. Die gängigsten Präparate sind hierbei PETN, ISMN, ISDN und NTG. Neuere insbesondere vorklinische Untersuchungen haben geholfen zu verstehen, dass es sich bei der Gruppe von organischen Nitraten um eine heterogene Gruppe von Substanzen handelt, die zum Teil signifikant unterschiedliche Effekte auf die Expression von schädlichen bzw. protektiven Genen im Gefäßsystem besitzen.

NTG wird primär zur Behandlung des akuten Angina‐pectoris‐Anfalls eingesetzt und im Rahmen eines akuten Koronarsyndroms, vor allem wenn gleichzeitig ein Bluthochdruck vorliegt, venös appliziert. ISMN und ISDN haben in der Therapie der stabilen AP deutlich an Bedeutung verloren, während PETN hierbei vermehrt eingesetzt wird.

In Bezug auf die Toleranzentwicklung und Induktion einer endothelialen Dysfunktion scheinen diese Nebenwirkungen für ISMN, NTG und ISDN zu gelten, während sie bei einer PETN‐Therapie nicht oder allenfalls reduziert beobachtet wurden.

Bei der Therapie der schweren Herzinsuffizienz stellt die Vasodilatantientherapie, bestehend aus ISDN und Hydralazin, eine gute Ergänzung zu der klassischen Herzinsuffizienz‐Therapie, bestehend aus Betablockern, Schleifendiuretika, Aldosteronantagonisten und ACE‐Hemmern bzw. Angiotensinrezeptorantagonisten, dar.
NO‐Donatoren bei der Therapie der Herzinsuffizienz. Größtes Problem: Toleranzentwicklung
Authors: Ukena Christian , Link Andreas , Böhm Michael
Published: September 2010

NO‐Donatoren haben aufgrund ihrer hämodynamischen Wirkungen positive Effekte bei Patienten mit Herzinsuffizienz. Zur Therapie der akuten Herzinsuffizienz sind Glyceroltrinitrat, Isosorbiddinitrat und Natrium‐Nitroprussid etabliert. Sie führen durch eine Reduktion der Vor‐ und Nachlast zu einer Stabilisierung des Patienten. Aufgrund der Toleranzentwicklung eignen sich NO‐Donatoren nur eingeschränkt zur Langzeittherapie. Bei der Behandlung der chronischen Herzinsuffizienz wird aktuell nur eine Kombinationstherapie aus Isosorbiddinitrat und Hydralazin in besonderen Situationen empfohlen. Das Nitrat Pentaerythrityltetranitrat nimmt aufgrund einer verminderten Toleranzentwicklung eine besondere Stellung ein. Die Wirkung dieses Medikaments bei Patienten mit chronischer Herzinsuffizienz und sekundärer pulmonaler Hypertonie wird aktuell in klinischen Studien untersucht.
Mechanismen und klinischer Stellenwert der Nitrattoleranz. Diversität und Nebenwirkungen organischer Nitrate
Authors: Daiber Andreas , Gori Tommaso , Münzel Thomas
Published: September 2010

Die wichtigste Beobachtung der letzten Jahre war, dass es sich bei den organischen Nitraten überraschenderweise um eine heterogene Gruppe von Vasodilatantien handelt, denen gemeinsam ist, dass sie die lösliche GC und die cGMP‐abhängige Kinase aktivieren können. Alle klinisch wichtigen organischen Nitrate (GTN, ISDN und ISMN) außer dem PETN induzieren eine Toleranzentwicklung und eine endotheliale Dysfunktion bei chronischer Gabe. Aktuelle Arbeiten konnten insbesondere nach Gabe von GTN einen neuen Toleranz‐Mechanismen identifizieren, der aus der Hemmung des Nitrat‐bioaktivierenden Enzyms, der mitochondrialen Aldehyddehydrogenase (ALDH‐2) sowie die Bildung reaktiver Sauerstoff‐ und Stickstoffspezies (RONS) in Mitochondrien besteht, die wiederum die Bioaktivierung des GTN hemmen. Damit konnten erstmals die beiden nun schon klassischen Konzepte der Nitrattoleranz, erhöhter oxidativer Stress und verminderte GTN‐Biotransformation, in ein Konzept übergeführt werden. Aktuelle tierexperimentelle und humane Studien legen nahe, dass die organischen Nitrate nicht als einheitliche homogene Gruppe anzusehen sind, sondern eine beachtliche Diversität hinsichtlich Induktion der Gefäßdysfunktion und insbesondere in der Fähigkeit, oxidativen Stress in den Gefäßen zu induzieren, zeigen. In der Vergangenheit wurde versucht, die Nitratwirkung vor allem durch das so genannte “Nitrat‐freie Intervall” zu erhalten, mit dem Nachteil des Stopps einer wichtigen antiischämischen Therapie. Momentan stellt das PETN, insbesondere mit seiner Fähigkeit, antioxidativ wirksame Enzymsysteme hochzuregulieren, das Nitrat der Wahl dar. Die klinische Wirksamkeit muss jedoch erst in großen “Multicenter‐Trials” bei Patienten mit Herzinsuffizienz und pulmonaler Hypertonie sowie bei Patienten mit stabiler KHK untersucht werden.
Therapie der Erektilen Dysfunktion. Stellenwert der PDE5‐Inhibitoren
Authors: Schubert‐Zsilavecz Manfred
Published: September 2010

Das Panel on the Treatment of Organic Erectile Dysfunction der amerikanischen urologischen Gesellschaft (AUA) hat festgestellt, dass das Ziel einer zuverlässigen Therapie der Erektilen Dysfunktion mit möglichst minimalen Nebenwirkungen und einfacher Anwendung erreicht werden sollte. Im Vergleich mit allen übrigen Arzneistoffen zur Therapie der Erektilen Dysfunktion erfüllen PDE5‐Hemmer diese Anforderungen am besten. Deren Wirksamkeit ist unzweifelhaft belegt: Sie verbessern die Fähigkeit, bei sexueller Stimulation eine Erektion zu erreichen und aufrecht zu erhalten, die für einen Geschlechtsverkehr ausreicht. PDE5‐Hemmer sind demzufolge keine “Lifestyle‐Arzneimittel” und schon gar nicht Wundermittel zur Potenzsteigerung. Vielmehr handelt es sich bei den PDE5‐Inhibitoren um eine seriöse Arzneistoffklasse, die es Paaren ermöglicht, wieder in normaler Häufigkeit Geschlechtsverkehr zu haben. Die gute Wirksamkeit in Verbindung mit dem sehr guten Sicherheitsprofil – bei strenger Berücksichtigung der Kontraindikationen – machen PDE5‐Hemmer aus aktueller Sicht zur bedeutendsten Wirkstoffklasse zur oralen Therapie der Erektilen Dysfunktion.
Sexual function in adolescent and young adult survivors of lower extremity bone tumors
Authors: Barrera Maru , Teall Tanya , Barr Ronald , Silva Mariana , Greenberg Mark
Published: September 2010

Background

Improving survival rates and new surgical options have led to increased interest regarding late effects and quality of life in adolescent and young adult survivors of bone cancers, including their sexual functioning. This study investigated sexual functioning in adolescent and young adult survivors of lower limb bone tumors, in relation to surgical treatments, gender differences, depressive symptoms, global self worth, and physical disability.

Procedure

Twenty‐eight participants (age range 18–32 years) completed measures of gender specific sexual function, depressive symptoms, global self worth, and physical disability. For analysis, surgical intervention was grouped into limb sparing surgeries (LS; allograft fusion and endoprosthesis) and amputation or Van Nes rotationplasty (AMP).

Results

Male survivors reported significantly higher scores than females on total sexual function scores (P = 0.050), sexual drive (P = 0.002), and frequency of sexual thoughts, fantasies or erotic dreams (P = 0.021). Men also reported significantly better physical functioning scores than women (P = 0.012). LS scored significantly lower on frequency of sexual thoughts, fantasies and erotic dreams (P = 0.048) and frequency of sexual experiences (P = 0.016) compared with AMP. In addition, LS reported significantly more depressive symptoms scores (P = 0.004) and lower self worth scores (P = 0.037), than AMP.

Conclusions

These results suggest that male survivors of lower extremity bone tumors experience better sexual functioning than women. Survivors of limb sparing surgeries struggle with sexual function, depressive symptoms, and poor self‐perception compared to Van Nes rotationplasty and amputation survivors. Pediatr Blood Cancer. 2010;55:1370–1376. © 2010 Wiley‐Liss, Inc.
Set‐LRP of MMA in acetic acid
Authors: Fleischmann Sven , Percec Virgil
Published: September 2010

Single‐electron transfer living radical polymerization (SET‐LRP) has emerged as a reliable, robust, and straight forward tool for the construction of well‐defined polymers. This manuscript reports on the influence of acidity on the SET‐LRP process. The SET‐LRP of methyl methacrylate initiated with tosyl chloride and catalyzed by Cu(0)/Me6‐TREN at 50 °C in protic solvent mixtures containing acetic acid is described. The polymerization kinetics was recorded in the presence of various amounts of acetic acid. Hereby it was found that the SET‐LRP process tolerates considerable acidity. The SET‐LRP of MMA comprising 1, 2.5, 10, and 25% acetic acid were well controlled. The reactions followed first‐order kinetic in monomer consumption and the molecular weights increased linearly with conversion while retaining narrow molecular weight distribution. In all cases, complete monomer conversion was achieved. Acetic acid could be also used as a solvent for the SET‐LRP of MMA. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010
Long‐term comparative trial of two different physiotherapy techniques; postural drainage with percussion and autogenic drainage, in the treatment of cystic fibrosis
Authors: McIlwaine Maggie , Wong Lawrence T , Chilvers Mark , Davidson George F.
Published: September 2010

In N. America, over the past decade, various airway clearance techniques (ACT) have been introduced for the treatment of cystic fibrosis (CF). We hypothesized that autogenic drainage (AD), an ACT developed in Belgium would be as effective as postural drainage with percussion (PD) in treating patients with CF.

Methods

Thirty‐six CF patients, aged 12–18 years, with Shwachman score 65–98, were enrolled in a 2‐year cross‐over trial. Patients were matched as pairs and members of each pair were randomly assigned to two groups. For the first study year, Group A performed PD while Group B performed AD. At the end of 1 year Groups A and B crossed over physiotherapy techniques. Clinical status and pulmonary function (FVC, FEV1, FEF25–75) were measured at 3 monthly intervals. Only results from the first year of the study are reported, as 10 out of 17 patients who had completed performing AD for the first year refused to change back to PD for the second year.

Results

During the first year of the study, both the AD and PD groups demonstrated improved pulmonary function with no significant difference between the two groups. Change in FVC and FEV1 percent predicted for Groups A and B was 0.47 ± 1.65se versus 2.35 ± 1.51se and 2.09 ± 2.2se versus 0.92 ± 2.25se. However, CF patients exhibited a marked preference for the AD technique. Results suggest that both AD and PD are effective methods of performing physiotherapy for CF patients and that the benefits of either technique are enhanced by measures which encourage adherence. Pediatr Pulmonol. 2010;45:1064–1069. © 2010 Wiley‐Liss, Inc.
Photochemical degradation of citrate buffers leads to covalent acetonation of recombinant protein therapeutics
Authors: Valliere‐Douglass John F. , Connell‐Crowley Lisa , Jensen Randy , Schnier Paul D. , Trilisky Egor , Leith Matt , Follstad Brian D. , Kerr Jennifer , Lewis Nathan , Vunnum Suresh , Treuheit Michael J. , Balland Alain , Wallace Alison
Published: September 2010

Novel acetone and aldimine covalent adducts were identified on the N‐termini and lysine side chains of recombinant monoclonal antibodies. Photochemical degradation of citrate buffers, in the presence of trace levels of iron, is demonstrated as the source of these modifications. The link between degradation of citrate and the observed protein modifications was conclusively established by tracking the citrate decomposition products and protein adducts resulting from photochemical degradation of isotope labeled 13C citrate by mass spectrometry. The structure of the acetone modification was determined by nuclear magnetic resonance (NMR) spectroscopy on modified–free glycine and found to correspond to acetone linked to the N‐terminus of the amino acid through a methyl carbon. Results from mass spectrometric fragmentation of glycine modified with an acetone adduct derived from 13C labeled citrate indicated that the three central carbons of citrate are incorporated onto protein amines in the presence of iron and light. While citrate is known to stoichiometrically decompose to acetone and CO2 through various intermediates in photochemical systems, it has never been shown to be a causative agent in protein carbonylation. Our results point to a previously unknown source for the generation of reactive carbonyl species. This work also highlights the potential deleterious impact of trace metals on recombinant protein therapeutics formulated in citrate buffers.
New insights into S2P signaling cascades: Regulation, variation, and conservation
Authors: Chen Gu , Zhang Xu
Published: September 2010

Regulated intramembrane proteolysis (RIP) is a conserved mechanism that regulates signal transduction across the membrane by recruiting membrane‐bound proteases to cleave membrane‐spanning regulatory proteins. As the first identified protease that performs RIP, the metalloprotease site‐2 protease (S2P) has received extensive study during the past decade, and an increasing number of S2P‐like proteases have been identified and studied in different organisms; however, some of their substrates and the related S1Ps remain elusive. Here, we review recent research on S2P cascades, including human S2P, E. coli RseP, B. subtilis SpoIVFB and the newly identified S2P homologs. We also discuss the variation and conservation of characterized S2P cascades. The conserved catalytic motif of S2P and prevalence of amino acids of low helical propensity in the transmembrane segments of the substrates suggest a conserved catalytic conformation and mechanism within the S2P family. The review also sheds light on future research on S2P cascades.
Non‐native interactions play an effective role in protein folding dynamics
Authors: Faísca Patrícia F. N. , Nunes Ana , Travasso Rui D.M. , Shakhnovich Eugene I.
Published: September 2010

Systematic Monte Carlo simulations of simple lattice models show that the final stage of protein folding is an ordered process where native contacts get locked (i.e., the residues come into contact and remain in contact for the duration of the folding process) in a well‐defined order. The detailed study of the folding dynamics of protein‐like sequences designed as to exhibit different contact energy distributions, as well as different degrees of sequence optimization (i.e., participation of non‐native interactions in the folding process), reveals significant differences in the corresponding locking scenarios—the collection of native contacts and their average locking times, which are largely ascribable to the dynamics of non‐native contacts. Furthermore, strong evidence for a positive role played by non‐native contacts at an early folding stage was also found. Interestingly, for topologically simple target structures, a positive interplay between native and non‐native contacts is observed also toward the end of the folding process, suggesting that non‐native contacts may indeed affect the overall folding process. For target models exhibiting clear two‐state kinetics, the relation between the nucleation mechanism of folding and the locking scenario is investigated. Our results suggest that the stabilization of the folding transition state can be achieved through the establishment of a very small network of native contacts that are the first to lock during the folding process.
Mechanical and electronic properties of carbon nanotube–graphene compounds
Authors: Artyukh A. A. , Chernozatonskii L. A. , Sorokin P. B.
Published: September 2010

Composite structures of graphene and carbon nanotubes (CNTs) have attracted great interest due to their expected distinguished properties. Here we have investigated the mechanical and electronic properties of new nanostructures based on CNT–graphene covalent‐bonded compounds.

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The process of the formation of the graphene–nanotube compound. Left: single graphene and nanotube (border atoms of graphene are highlighted). Right: carbon nanotube–graphene composite.
Study of the mechanical response of carbon nanotubes‐SU8 composites by nanoindentation
Authors: Mionić Marijana , Jiguet Sébastien , Judelewicz Moshe , Karimi Ayat , Forró László , Magrez Arnaud
Published: September 2010

Multiwalled carbon nanotubes (MWCNTs)/SU8 composites have been produced to enhance the mechanical properties of SU8 photoresist. We have studied the influence of SU8 solvent on the structural homogeneity of composites through nanoindentation testing. It is found that acetone and propylene glycol methyl ether acetate (PGMEA) are very suitable solvents to prepare MWCNTs/SU8 composites with significant increase of the Young's modulus (EY). The highest increase of EY in respect to the parent material of 104% was obtained with acetone as solvent. It was noticed that the remaining solvent in the composite influences strongly EY, as well.
A combined photoemission and ab initio study of the electronic structure of (6,4)/(6,5) enriched single wall carbon nanotubes
Authors: Blauwe Katrien De , Miyata Yasumitsu , Ayala Paola , Shiozawa Hidetsugu , Mowbray Duncan J. , Rubio Angel , Hoffmann P. , Kataura Hiromichi , Pichler Thomas
Published: September 2010

Due to the growing number of applications of small diameter single wall carbon nanotubes (SWCNTs) in opto‐electronics and biological imaging, there is a strong need for a better understanding of their electronic properties. Because (6,5) tubes with a diameter of 0.75 nm are currently the strongest enriched in the CoMoCat synthesis process, they are one of the most studied carbon nanotubes. However, there is still a lack of knowledge on the electronic properties of these tubes. In this paper, we report on a detailed analysis of the electronic structure of (6,4)/(6,5) enriched nanotubes with a combined experimental and theoretical approach. From photoemission the detailed C1s and valence band response of these narrow diameter tubes is studied. The observed electronic structure is in sound agreement with state of the art ab initio calculations using density functional theory.
Raman response from double‐wall carbon nanotubes based on metallicity selected host SWCNTs
Authors: Simon F. , Kramberger C. , Peterlik H. , Pfeiffer R. , De Blauwe K. , Pichler T. , Kuzmany H. , Yanagi K. , Miyata Y. , Kataura H.
Published: September 2010

We studied SWCNTs and derivatives separated according to their metallicity using X‐ray diffractometry, optical absorption, and Raman spectroscopy. The X‐ray study evidences a complete absence of graphite and metal catalysts. Optical absorption shows that the metallic sample is of high purity, however, a small amount of metallic tubes are present in the semiconducting sample. We synthesized double‐wall carbon nanotubes from the separated SWCNTs by filling‐in C60's and heating these samples. The Raman spectra of the inner tubes are markedly distinct in the two types of samples and also allows to characterize the efficiency of the separation.
Site‐selective deposition of single‐wall carbon nanotubes by patterning self‐assembled monolayer for application to thin‐film transistors
Authors: Fujii Shunjiro , Tanaka Takeshi , Suga Hiroshi , Naitoh Yasuhisa , Minari Takeo , Tsukagoshi Kazuhito , Kataura Hiromichi
Published: September 2010

We have demonstrated a site‐selective deposition of uniform single‐wall carbon nanotube (SWCNT) thin films on a SiO2/Si substrate using patterned self‐assembled monolayers (SAMs). Non‐polar octadecyltrichlorosilane (OTS) SAM was patterned by ultraviolet (UV) light through shadow mask. Then polar 3‐aminopropyltriethoxysilane (APTES) SAM was selectively formed at the channel area of thin film transistors (TFTs). Finally, SWCNT thin films were selectively deposited on the TFT channel using these patterned SAMs. In this work, 25 TFTs were fabricated simultaneously on the same substrate using semiconductor‐enriched SWCNTs (s‐SWCNTs) solution. As a result, 23 TFTs showed high on/off current ratios over 104 without any post‐treatment. It was confirmed that this method is useful to produce a large number of TFTs at a same time and applicable to the low cost production of SWCNT‐integrated circuits in near future.
Impacts of fluorine on GaN high electron mobility transistors: Theoretical study
Authors: Hong Ki‐Ha , Hwang Injun , Choi Hyuk Soon , Oh Jaejoon , Shin Jaikwang , Chung U‐In , Kim Jongseob
Published: September 2010

We investigate the role of fluorine (F) in GaN‐based high electron mobility transistors (HEMTs) with first principle calculations. Formation energy calculations of F in GaN and AlN reveal that energetically favored interstitial F (Fi) and substitutional F at N sites (FN) could play important roles in the performance of HEMTs. Fiis responsible for positive threshold voltage (Vth) shift by forming F–anion and depleting 2DEG carriers. The degradation of device performance at high temperature is ascribed to the defect energy state near conduction band edge of FN. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Investigation of electron delay in the base on noise performance in InGaP heterojunction bipolar transistors
Authors: Shimukovitch A. , Sakalas P. , Zampardi P. , Schroter M. , Matulionis A.
Published: September 2010

The DC, RF and noise characteristics of InGaP/GaAs heterojunction bipolar transistors (HBTs) with different base layer widths and δ‐doped layer in the collector were investigated. Analysis of the RF and noise characteristics revealed that the high frequency noise of these HBTs is reduced due to cross‐correlation of shot noise sources and Coulomb blockade from accumulated charge. The measured noise performance is in a good agreement with the HICUM L2 compact model [M. Schroter, IEICE Trans. Electron. E88‐C, 1098 (2005)] when correlated shot noise sources with Fano factor for collector shot noise are included.

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Doping and content profiles of the investigated InGaP HBTs.

(© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Invisible Scar Endoscopic Dorsal Approach Thyroidectomy: A Clinical Feasibility Study
Authors: Schardey Hans Martin , Barone Mirko , Pörtl Stefan , von Ahnen Martin , von Ahnen Thomas , Schopf Stefan
Published: September 2010

Background

The aim of the present study was to test the safety and feasibility of the dorsal approach endoscopic thyroidectomy procedure in a prospective trial in humans, after the procedure had been developed ex vivo in human cadavers.

Methods

A total of 28 patients were enrolled for 30 unilateral procedures of thyroidectomy. Two cases were staged bilateral procedures. Patients presenting with suspicious cold nodules, hot nodules, or goiters were operated on under general anaesthesia. Skin incision is carried out on the scalp, behind the ear. Deep to the sternocleidomastoid muscle, but respecting the superficial cervical fascia, the preparation goes past the carotid triangle to reach the thyroid below the straight neck muscles. Postoperatively the patients underwent neurological assessment, vocal cord examination, clinical control for hemorrhage, and determination of serum levels of Ca2+.

Results

Thirty unilateral procedures by the dorsal approach were carried out in 22 women and 6 men. There was 1 subtotal thyroidectomy and 29 total unilateral thyroidectomies with no conversions. There was one permanent recurrent laryngeal nerve (RLN) lesion and one postoperative hemorrhage. The size of the lobes removed ranged from 6 to 40 ml (mean: 18 ml). In four cases the specimen exceeded 38 ml. There was one multifocal papillary cancer requiring open surgical revision and lymphadenectomy. The other diagnoses were benign. All wounds healed by primary intention. Temporary impairment of cervical nerves was detected in six patients. It was possible to avoid access‐related problems by improving the patient’s positioning on the operating table, omitting straight instruments, and respecting the superficial fascia before entering the carotid triangle.

Conclusions

Hemithyroidectomy by the dorsal approach is feasible. It is a single surgeon, single port, gasless unilateral endoscopic technique with the option to go bilateral.
The Development of a Methodology for Examining the Process of Family Communication of Genetic Test Results
Authors: Smith Jonathan A. , Dancyger Caroline , Wallace Melissa , Jacobs Chris , Michie Susan
Published: September 2010

It is important to study communication processes in families where members are undergoing testing for genetic conditions because the information received from such testing is crucial not just to the individual concerned but also to other members of the biological family. This topic has received little research attention, in part because of the complexities of methodology required. In this paper we present the development of a method specifically designed for the examination of the content and process of communication of genetic information in families. The method aims to maximize ecological validity as far as is possible. We describe how participants and other family members are recruited and how data were collected. We outline three main data analytic strategies: a graphic to show how genetic information changes as it flows from clinic and through the family, an intensive qualitative analysis of the meaning and impact of the genetic information to different family members, and an informative genogram which plots key family dynamics. This method will be illustrated in relation to a study of ten family‐groups where one individual has been found to carry a genetic mutation predisposing them to hereditary breast and ovarian cancer.
Gradual Reduction of Chronic Fracture Dislocation of the Ankle Using Ilizarov/Taylor Spatial Frame
Authors: Tellisi Nazzar , Deland Jonathan T. , Rozbruch S. Robert
Published: September 2010

With the advances in trauma care, chronic fracture dislocation of the ankle is not a condition commonly seen in modern clinical practice. When encountered, it can be difficult to preserve the ankle joint. We present a case of a 65-year-old female, with a chronic fracture dislocation of the ankle. The ankle joint was subluxated with posterior translation of the talus, displacement of the posterior malleolus fragment, and a distal fibula fracture. A minimally traumatic approach was devised to treat this complex fracture dislocation which included gradual reduction of the ankle with a Taylor spatial frame, followed by stabilization with internal fixation and removal of the frame. Bony union and restoration of the ankle joint congruency was achieved.
Signal transduction and signal transmission
Authors: Gießl A. , Regus-Leidig H. , Brandstätter J. H.
Published: September 2010

Vision begins in highly specialized light-sensing neurons, the rod and cone photoreceptors. Their task is to absorb photons, transduce the physical stimulus into neuronal sig­nals, transmit the signals to the parallel signal processing pathways of the subsequent reti­nal network with the highest possible fidelity and continuously adapt to changes in stim­ulus intensities. If you imagine a pitch-black night with only a few photons hitting the ret­ina and being absorbed by the photoreceptors and a bright sunny day with the photore­ceptors being bombarded by billions of photons, you realize that a photoreceptor faces two fundamental challenges: it has to detect the light signal with the greatest sensitivity, e.g. a single photon leads to a change in the membrane potential of a rod photoreceptor and, at the same time, encode light intensities covering a broad dynamic range of sev­eral orders of magnitude. To fulfill these demands, photoreceptors have developed separate, structurally and functionally specialized compartments, which are the topic of this article: the outer segment for signal transduc­tion and the terminal with its highly complex ribbon synapse for signal transmission.
Artificial implants for the regeneration of peripheral nerves
Authors: Koxholt I. , Mey J.
Published: September 2010

Axonal regeneration is possible in the pe­ripheral nervous system. Therefore, nerve le­sions can be cured by suturing the dissoci­ated nerve stumps or by grafting an autol­ogous nerve. Since nerve transplantations cause a sensory deficit at the donor site, it is desirable to develop artificial implants for nerve regeneration. Artificial implants have to promote and guide axonal growth, the migration of Schwann cells and must not cause inflammation. Hollow tubes as nerve bridges are already used in the clinic. However, with these it is not possible to achieve nerve re­generation over distances much longer than 30 mm. For this purpose, a number of natural and synthetic materials have already been tested. Biocompatible tubes are being developed which contain orientated fibers or gels with longitudinal channels. In addition, artificial guidance materials are endowed with specific biological functions. Most frequently, extracellular matrix proteins or synthet­ic peptides that activate integrin receptors are coupled to the materials. Other approach­es use gradients of neurotrophins or incorporate living cells. In the long run, a major goal of research is to develop cell-free artificial implants which allow a similar degree of regen­eration as is possible with autologous nerve transplants.
ON-FARM ASSESSMENT OF CLONAL INTRODUCTION OF ROOT CROPS DIVERSITY IN VANUATU, MELANESIA
Authors: CAMUS P. , LEBOT V.
Published: September 2010

Ex-situ collections of vegetatively propagated root crops are difficult to maintain in developing countries. On-farm conservation could be a solution but is more complex for vegetatively propagated than for sexually propagated species. In Vanuatu, a Melanesian archipelago where yam, taro, sweet potato and cassava are staples, a study was undertaken to develop an on-farm conservation system based on the geographic distribution of allelic diversity. Two years after the introduction of new varieties, a survey was conducted with 449 farmers located on 10 different islands. In order to evaluate on-farm conservation efficiency, qualitative and quantitative investigations were conducted and data were analysed. The conclusion was that farmers do enrich their varietal portfolios with introduced exotic genotypes thus broadening the narrow genetic bases of some species. Nevertheless, no local varieties were lost. Significant geographic distribution of clones of new varieties throughout the archipelago also took place via spontaneous, informal distribution to farmers' relatives. These encouraging results point to the potential impact of the geographic distribution of allelic diversity on smallholders' varietal portfolios. On-farm conservation appears to be an appropriate strategy for the conservation of root crop germplasm diversity in Vanuatu. Potential applications for transfer of the methodology to other locations are discussed.
Relationship between growth behaviour, micro and macroscopic morphologies and freezing sensitivity of the ripening starterGeotrichum candidumis strain specific and mostly related to the morphotypes: the arthrospores/hyphae parameter
Authors: Missous Ghalia , Thammavongs Bouachanh , Launay Géraldine , Guéguen Micheline , Dieuleveux Virginie , Panoff Jean-Michel
Published: September 2010

Microscopic conformation, growth behaviour and freezing sensitivity of seven strains ofGeotrichum candidum, a ripening starter, were studied and compared according to their macroscopic morphotypes. It has been shown that the thallus forming units (TFU)×ml−1/OD600nmratio as a function of time is an interesting parameter to followG. candidumsporulation through the growth behaviour. Microscopic conformation, growth behaviour and freezing sensitivity are clearly strain specific and mostly related to their corresponding morphotypes “yeast”, “mould” or “intermediate”. The two “mould” strains that sporulate weakly (UCMA103, UCMA499) showed a low survival rate to freezing stress whereas the “yeast” strains expressed a significant resistance owing to the arthrospore abundance. Interestingly, one strain (UCMA96) which appeared on solid medium in accord with the “mould” morphotype respond similarly to freezing stress.
Major lipids and fatty acids in the liver and rumen fluid of the goat (Capra hircus) infected with the trematodeParamphistomum cervi
Authors: Ghosh D. , Misra K.K.
Published: September 2010

The present study records the occurrence of major lipid fractions and their fatty acids in a digenetic trematode parasiteParamphistomum cervi, and the rumen fluid and liver of the goat (Capra hircus). The amount of neutral lipids (NL), glycolipids (GL) and phospholipids (PL) of goat liver, rumen fluid and of the parasite shows that the rumen fluid is rich in NL, which is also in maximum quantity in the parasite, while the liver is rich in PL followed by NL. The number of fatty acids of total lipids (TL), NL and PL is greater in the parasite than those of the liver and rumen fluid. The number of fatty acids of GL is higher in the liver than in the parasite and the rumen fluid. Comparison of unsaturated fatty acid (UFA), C18total and C18UFA of TL, NL, GL and PL of the liver, rumen fluid and the parasite shows that the amount of C18UFA is higher inP. cerviin all the lipid fractions, except for GL, than in the rumen fluid and the liver. The results reveal thatP. cerviabsorbs a greater number of fatty acids than its host.
Sepúlveda, Las Casas, and the Other: Exploring the Tension between Moral Universalism and Alterity
Authors: Brunstetter Daniel R.
Published: September 2010

Modern politics is at times a balancing act between universal claims about the human (equal rights, dignity, and respect) and political actions which may seem to violate these claims (torture, just wars, repudiation of certain cultural practices, tacit discrimination). An exploration of some of the philosophical roots of the modern understanding of the person, when it was the subject of debate, provides a perspective at the origin of Modernity from which to evaluate the tenuous relationship between moral universalism and alterity at the heart of this tension. The debates at Valladolid in 1550–51 between Las Casas and Sepúlveda, arguing their conceptions of the human, can shed light on how and why arguments for inequality creep back into the modern discourse on alterity. The lessons from Valladolid, therefore, might help to limit or clarify recourse to such arguments.
The Beginning that Never Was: Mediation and Freedom in Rousseau's Political Thought
Authors: Einspahr Jennifer
Published: September 2010

Upon close examination of Rousseau's accounts of human development, we find that Rousseau presents us with paradoxical chronologies in which the experience of supposed immediacy from which humans are said to originate always seems to be informed by, and even require, previous mediation. More specifically, reflection, comparison, and imagination are thought to exist only after the onset of perfectibility, but these mediating capacities are always already present in pity and self-love, as well as for the “independent” savage, calling into question the possibility that any human sentiment or condition could be immediately accessible and fundamentally imbuing human life with ambiguity, fluidity, and disorder. Consequently, morality and freedom for Rousseau require the negotiation, stabilization, or management of the unstable “things between” human beings and their experiences, the object world, and others, even as such management is best hidden from view and experienced as given and true.
Rousseau's Use of the Jewish Example
Authors: Marks Jonathan D.
Published: September 2010

Rousseau refers to the Jews in major and minor works, setting them alongside the Greeks and Romans as models for republican politics. Yet Rousseau's use of the Jewish example has been almost entirely neglected. I argue that this example, which for Rousseau stands between paganism and Christianity, plays a unique role in Rousseau's political thought. In particular, Judaism, as Rousseau presents it, surpasses Christianity in its this-worldly emphasis on compassion and justice, an emphasis that even the classical republics that are Rousseau's usual models for social and political well-being cannot match. It does so, moreover, without fostering the dogmatism that, along with Christian otherworldiness, has, in Rousseau's estimation, helped to spoil European politics.
Genocide: Clarifying Concepts and Causes of Cruelty
Authors: Verdeja Ernesto
Published: September 2010

In the decades after World War Two, most scholars working on genocide focused on particular cases, providing historically detailed descriptions of the causes and patterns of mass violence but rarely branching out beyond a specific case. The study of the Holocaust is typical of this; the vast majority of works on the Nazi genocide had little comparative dimension and instead examined the ways in which anti-Semitism and certain policies condemned disfavored minorities to persecution and extermination. These earlier works are particularly important because they gave us rich understandings of the origins, sequencing, and dynamics of mass violence, as well as the roles of dehumanizing cultural views and ideologies that facilitated extermination. Nevertheless, multi-case studies were the exception, and generally received little attention in the social sciences.
Quiet time meridional (vertical) ion drifts at low and middle latitudes observed by ROCSAT‐1
Authors: Pacheco E. E. , Heelis R. A. , Su S.‐Y.
Published: September 2010

In situ ion drift observations from the ROCSAT‐1 satellite, near the 600 km altitude and for the years 1999–2003, are used to describe variations in the local time (LT) distribution of meridional E × B drifts at low and middle latitudes, for different longitudes and seasons. We derive the ion drifts in the direction perpendicular to the magnetic field during quiet times defined by Kp ≤ 3 and Dst > −100 nT. Offsets in the original data are removed by considering separately the northbound and southbound passes in a given volume and by enforcing magnetic conjugacy for the ion drift components perpendicular to the magnetic field. Three major features are identified for which the variations in latitude, longitude, and season allow the major drivers of these features to be indicated: (1) a latitude/magnetic apex height variation in the prereversal (after sunset) enhancement of the vertical drift that is attributed to similar variations in the flux tube–integrated Pedersen conductivity, (2) the daytime meridional drifts that are largely driven by the E region dynamo show significant latitude variations that are attributed to the relative importance of diurnal and semidiurnal wind fields as a function of latitude, and (3) a downward enhancement of the ion drift before sunrise is attributed to a reversal in the F region zonal wind during the nighttime.
Particle‐resolved simulation of aerosol size, composition, mixing state, and the associated optical and cloud condensation nuclei activation properties in an evolving urban plume
Authors: Zaveri Rahul A. , Barnard James C. , Easter Richard C. , Riemer Nicole , West Matthew
Published: September 2010

The recently developed particle‐resolved aerosol box model PartMC‐MOSAIC (Particle Monte Carlo model–Model for Simulating Aerosol Interactions and Chemistry) was used to rigorously simulate the evolution of aerosol mixing state and the associated optical and cloud condensation nuclei (CCN) activation properties in an idealized urban plume. The model explicitly resolved the size and composition of individual particles from a number of sources and tracked their evolution due to condensation, evaporation, coagulation, emission, and dilution. The ensemble black carbon (BC)–specific absorption cross section increased by 40% over the course of 2 days due to BC aging by condensation and coagulation. Threefold and fourfold enhancements in CCN/CN ratios were predicted to occur within 6 h for 0.2% and 0.5% supersaturations (S), respectively. The particle‐resolved results were used to evaluate the errors in the optical and CCN activation properties that would be predicted by a conventional sectional framework that assumes monodisperse, internally mixed particles within each bin. This assumption artificially increased the ensemble BC‐specific absorption by 14–30% and decreased the single scattering albedo (SSA) by 0.03–0.07, while the bin resolution had a negligible effect. In contrast, the errors in CCN/CN ratios were sensitive to the bin resolution for a chosen supersaturation. For S = 0.2%, the CCN/CN ratio predicted using 100 internally mixed bins was up to 25% higher than the particle‐resolved results, while it was up to 125% higher using 10 internally mixed bins. Neglecting coagulation overpredicted aerosol water content and number concentrations (<0.2 μm), causing errors in SSA from  −0.02 to 0.035 and overprediction of CCN concentrations by 25–80% at S = 0.5%.
Air temperature variations on the Atlantic‐Arctic boundary since 1802
Authors: Wood Kevin R. , Overland James E. , Jónsson Trausti , Smoliak Brian V.
Published: September 2010

A two‐hundred year instrumental record of annual surface air temperature in the Atlantic‐Arctic boundary region was reconstructed from four station‐based composite time series. The new time series adds seventy‐six years to the previously available record. Credibility is supported by ice core records, other temperature proxies, and historical evidence. This record provides new perspective on past climate fluctuations in a region where pivotal climate system processes occur and where unexplained low‐frequency variations were observed during the 20th century. It is well correlated with sea‐surface temperature anomalies, both regionally and in the vicinity of the North Atlantic western boundary current and southern recirculation gyre. The extended instrumental record reveals an irregular pattern of decadal‐scale temperature fluctuations over the past two centuries. The early 20th century warming event is by far the most striking historical example.
Winter 2009–2010: A case study of an extreme Arctic Oscillation event
Authors: Cohen Judah , Foster James , Barlow Mathew , Saito Kazuyuki , Jones Justin
Published: September 2010

Winter 2009–2010 made headlines for extreme cold and snow in most of the major population centers of the industrialized countries of the Northern Hemisphere (NH). The major teleconnection patterns of the Northern Hemisphere, El Niño/Southern Oscillation (ENSO) and the Arctic Oscillation (AO) were of moderate to strong amplitude, making both potentially key players during the winter of 2009–2010. The dominant NH winter circulation pattern can be shown to have originated with a two‐way stratosphere‐troposphere interaction forced by Eurasian land surface and lower tropospheric atmospheric conditions during autumn. This cycle occurred twice in relatively quick succession contributing to the record low values of the AO observed. Using a skillful winter temperature forecast, it is shown that the AO explained a greater variance of the observed temperature pattern across the extratropical landmasses of the NH than did ENSO.