bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultra‐fast mass fingerprinting by high‐affinity capture of peptides and proteins on derivatized poly(glycidyl methacrylate/divinylbenzene) for the analysis of serum and cell lysates
Authors: Rainer Matthias , Muhammad Najam‐ul‐Haq , Huck Christian W. , Feuerstein Isabel , Bakry Rania , Huber Lukas A. , Gjerde Douglas T. , Zou Xiajuan , Qian Honggang , Du Xiaojuan , Wei‐Gang Fang , Ke Yang , Bonn Günther K.
Published: September 2006

The development of support materials in mass fingerprinting is an important task required for diagnostic markers in conjunction with matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS). The material‐based approach, which we introduced as material‐enhanced laser desorption/ionization (MELDI), focuses not only on different functionalities, but also emphasizes the morphology, i.e. porosity or particle size of the carrier material. As a result, it provides a quick and sensitive platform for effective binding of peptides and proteins out of different biofluids, e.g. serum, spinal fluid, urine or cell lysates, and to subsequently analyze them with MALDI‐TOF MS. This approach includes a built‐in desalting step for serum protein profiling and is sensitive enough to detect proteins and peptides down to 100 fmol/µL. Here we co‐polymerized glycidyl methacrylate (GMA) with divinylbenzene (DVB) using thermal polymerization to yield a GMA/DVB polymer for further modifications. Different affinities have been created, such as immobilized metal ion affinity (IDA‐Cu2+), reversed‐phase (RP) and anion‐exchanger (AX) chromatography. The diverse derivatizations and the dispersity of the particles created by different chemical synthetic approaches were confirmed by characteristic infrared (IR) peaks. The polymerization carried out by non‐stirring yielded an average pore radius of 6.1 µm (macro‐pores) that enhanced the binding capacity enormously by offering enlarged surface areas. Moreover, atomic absorption spectrometry (AAS) provided the metal content loaded on iminodiacetic acid (IDA) in the case of poly(GMA/DVB)‐IDA‐Cu2+. To summarize, the optimized MELDI approach is sensitive in its performance, extremely fast and can be adapted to robotic systems for routine analysis, allowing sample preparation in less than 5 min in contrast to the conventional surface‐enhanced laser desorption/ionization (SELDI) methods. Copyright © 2006 John Wiley & Sons, Ltd.
Interactions between respiratory syncytial virus and the host cell: opportunities for antivirus strategies?
Authors: Sugrue Richard J.
Published: September 2006

At the start of the 21st century, respiratory syncytial virus (RSV) remains a serious global health concern. Although RSV has traditionally been acknowledged as a leading cause of morbidity and mortality in the paediatric population, the elderly and people with suppressed immune systems are now also recognised as being at risk from serious RSV infection. This problem is currently exacerbated by the lack of an effective vaccine to prevent RSV infection. Although the virus proteins play a variety of roles during the virus replication cycle, in many cases these tasks are performed via specific interactions with host-cell factors, including proteins, carbohydrates and lipids. The way in which RSV interacts with the host cell is currently being examined using a battery of different techniques, which encompass several scientific disciplines. This is providing new and interesting insights into how RSV interacts with the host cell at the molecular level, which in turn is offering the hope of new strategies to prevent RSV infection.
Current state of diagnosis and endovascular treatment of renal artery stenosis
Authors: Zeller
Published: September 2006

Renal artery stenosis may cause or deteriorate arterial hypertension and/or renal insufficiency. Technical improvements of diagnostic and interventional endovascular tools have lead to a more widespread use of endoluminal renal artery revascularization and extension of the indications for this type of therapy. Since the first renal artery angioplasties performed by Felix Mahler and Andreas Grüntzig in 1978, numerous single centre studies have reported the beneficial effect of percutaneous transluminal renal angioplasty, and since the early 1990’s stenting of renal artery stenosis caused either by atherosclerosis or fibromuscular dysplasia. This article summarizes the impact of technical improvements of endovascular tools on interventional techniques during the last decade and gives an overview concerning the clinical impact of renal artery revascularization. Despite the absence of sufficient randomized studies there is nonetheless evidence that stenting of hemodynamically relevant atherosclerotic renal artery stenosis has an impact on blood pressure control, renal function, and left ventricular hypertrophy.
Invasive therapeutic options in truncal varicosity of the great saphenous vein
Authors: Hach-Wunderle  , Hach
Published: September 2006

It is known from current pathophysiology that disease stages I and II of truncal varicosity of the great saphenous vein do not cause changes in venous pressure on dynamic phlebodynamometry. This is possibly also the case for mild cases of the disease in stage III. In pronounced cases of stage III and all cases of stage IV, however, venous hypertension occurs which triggers the symptoms of secondary deep venous insufficiency and all the complications of chronic venous insufficiency. From these facts the therapeutic consequence is inferred that in stages I and II and perhaps also in very mild cases of stage III disease, it is enough "merely" to remove varicose veins without expecting there to be any other serious complications in the patient’s further life caused by the varicosity. Recurrence rates are not included in this analysis. In marked cases of disease stages III and IV of the great saphenous vein, however, secondary deep venous insufficiency is to be expected sooner or later. The classical operation with saphenofemoral high ligation ("crossectomy") and stripping strictly adheres to the recognized pathophysiologic principles. It also takes into account in the greatest detail aspects of minimally invasive surgery and esthetics. In the past few years, developments have been advanced to further minimize surgical trauma and to replace the stripping maneuver using occlusion of the trunk vein which is left in place. Obliteration of the vessel is subsequently performed via transmission of energy through an inserted catheter. This includes the techniques of radiofrequency ablation and endovenous laser treatment. High ligation is not performed as a matter of principle. In a similar way, sclerotherapy using microfoam is minimally invasive in character. All these procedures may be indicated for disease stages I and II, and with reservations also in mild forms of stage III disease. Perhaps high ligation previously constituted overtreatment in some cases. Targeted studies are still needed to prove whether secondary deep venous insufficiency can be avoided in advanced stages of varicose vein disease without high ligation and thus without exclusion of the whole recirculation circuit.
Skin cholesterol: test performance, evaluation of potential determinants and correlation analysis with cardiovascular risk factors and circulating markers of inflammation
Authors: Reiter  , Wirth  , Pourazim  , Exner  , Baghestanian  , Rumpold  , Minar  , Bucek
Published: September 2006

Background: Skin cholesterol (SkC) has been suggested to be an additional risk predictor, so we evaluated the test performance, potential determinants of this marker as well as a potential correlation of SkC with markers of inflammation and the history of cardiovascular events. Patients and methods: SkC, determined by the non-invasive PREVU POC Skin Sterol test, as well as serum lipids, the body fat status, high-sensitive CRP (hs-CRP) and serum amyloid A (SAA) were evaluated in consecutive patients with and without documented atherosclerotic disease. Results: SkC was assessed in 201 patients. The within-day precision (CV) was 3.8%, the day-to-day CV of the right hand was 8.6% and 4.3% for the left hand, respectively. Neither univariate analysis nor multiple regressions identified a significant influence of age, sex, serum lipids, body fat status, smoking or diabetes mellitus on SkC, corresponding results were observed in a further analysis including 174 of these patients concerning hs-CRP and SAA (all p > 0.05). T-test analyses detected no significant differences between patients with and without a history of coronary, peripheral vascular and cerebrovascular events (all p > 0.05). Conclusions: The PREVU POC Skin Sterol test for the assessment of SkC proved an acceptable test performance. SkC is independent from serum lipids, traditional cardiovascular risk factors, two sensitive markers of systemic inflammation as well as the history of cardiovascular events indicating that the perception of this parameter as an established marker of vascular disease is premature.
Aspirin in peripheral arterial disease: breakthrough or pitfall?
Authors: Singer  , Imfeld  , Hoffmann  , Buschmann  , Labs  , Jaeger
Published: September 2006

Background: This paper introduces a proof-of-concept trial in progress, supposedly providing new important information on anti-platelet drugs used in patients with peripheral arterial disease (PAD). The Arteriogenesis Competence Network (Art.Net.) of the Universities of Basel, Berlin, and Freiburg could show in animal models that Aspirin (ASA), in contrast to Clopidogrel, inhibits the formation of an appropriate collateral network (arteriogenesis). This trial is supposed to reproduce the animal data in man. Materials and methods: In a prospective, double-blind, parallel-group, bi-national (D, CH), multicentre trial, 250 patients will be randomised to either 100 mg ASA or 75 mg Clopidogrel once daily. Patients will then enter a three months structured rehabilitation programme with daily physical training supposed to induce arteriogenesis. The claudication distances will be tested as the primary endpoint at baseline, 6 weeks, and at 3 months. Also, the 24h physical activity profile of all patients will be electronically documented. Conclusions: This trial will provide information on potential disadvantages when using ASA in PAD patients. If data emerging from animal pharmacology can be reproduced in man, the present standard scheme of anti-aggregant treatment in PAD patients has to be reconsidered.
Quality of life improvement after hospital-	based rehabilitation or home-based physical training in intermittent claudication
Authors: Imfeld  , Singer  , Degischer  , Aschwanden  , Thalhammer  , Labs  , Jaeger
Published: September 2006

Background: The magnitude of potential changes in Quality-of-Life (QoL) after structured institution-based or home-based peripheral arterial disease (PAD) rehabilitation programs are largely unknown at present. This pilot study provides first QoL data after PAD rehabilitation or a home-based PAD training. Patients and methods: In a non-randomized, open-label pilot study three groups of out-patients were compared: group 1 (n = 18) PAD rehabilitation; group 2 (n = 17) PAD rehabilitation + clopidogrel 75 mg once daily; group 3 (n = 20) home-based training. The training period was 3 months, which was followed by a 3-month observation phase (without prescribed training). The institution-based rehabilitation program consisted of 3 training hours per week whereas patients training at home were instructed to walk for 1 hour per day on an outdoor track. QoL assessment was performed using MOS SF-36, PAVK-86 and PAD-WIQ questionnaires. Results: At baseline background variables, demographics and claudication distances were comparable between groups. After three months of training the percentage changes for the initial and the absolute claudication distance (ICD, ACD) for groups 1, 2, and 3 amounted to 164%, 201%, 44% (ICD) and 83%, 131%, 5% (ACD), respectively. Statistically significant QoL improvements were recorded for physical functions, pain and disease related anxiety in all three study groups; statistically significant inter-group differences were not found. Conclusions: In sharp contrast to the development of the claudication distances the improvement in QoL, found after 3months of training, was comparable and not consistently different between the groups.
Results of different operative procedures for patients with popliteal artery aneurysms
Authors: Kopp  , Cascio  , Weidenhagen  , Stelter  , Meimarakis  , Lauterjung
Published: September 2006

Background: Long term results of four different operative procedures for the treatment of popliteal artery aneurysms were investigated either performed by short venous or segmental alloplastic interpositions or long femoro-popliteal below the knee bypass using alloplastic grafts or autologous vein. Patients and methods: 47 patients treated for 50 popliteal aneurysms (mean diameter ± SD: 3.5 ± 1.1 cm) were analyzed (follow-up: 40.2 ± 4.9 months). Results: Primary patency rate was 78% and secondary patency rate was 86% at 5 years. Frequency of operative reinterventions was higher in patients treated for acute ischemia and in patients treated with alloplastic interpositions or alloplastic bypass (p = 0.026). Secondary patency rates were higher in patients treated with autologous venous interpositions or venous femoro-popliteal bypass (p = 0.022). Times of secondary vascular patency were significantly shorter for patients treated with short alloplastic interpositions in comparison to long alloplastic femoro-popliteal bypass procedures, short venous interpositions or long venous bypass operations (p = 0.018). Conclusions: For the treatment of patients with popliteal aneurysms autologous venous interposition is therefore recommended or as an alternative venous or alloplastic femoro-popliteal below the knee bypass.
Balloon venoplasty of acute subclavian vein thrombosis
Authors: Müller-Bühl  , Kralj  , Strecker
Published: September 2006

Two patients with subclavian vein thrombosis are presented in which a balloon venoplasty led to recanalization of the subclavian vein and complete remission of clinical symptoms. In patients with extreme symptoms and unsuccessful initial catheter-directed local thrombolysis, this non-operative approach can be considered despite known favourable spontaneous outcome of subclavian vein thrombosis.
Embolization for asymptomatic aneurysms of the first jejunal artery
Authors: Shimohira  , Ogino  , Kitase  , Takeuchi  , Shibamoto
Published: September 2006

In a 71-year-old man with a history of coronary artery bypassing using the left internal thoracic and gastroepiploic arteries, the first jejunal artery aneurysms were found by chance at 3D-CT performed to evaluate conditions of the grafts. He was successfully treated by transcatheter embolization using interlocking detachable coils. During a follow-up period of 5 months, the patient did well and had no sign of intestinal ischemia.
Das Truncus coeliacus Aneurysma: Eine seltene Ursache abdomineller Beschwerden
Authors: Overhaus  , Lauschke  , Schäfer  , Lohmaier  , Hirner  , Mommertz
Published: September 2006

Viszeralarterienaneurysmen (VAA) repräsentieren 0.1– 0.2% aller vaskulärer Aneurysmen. Als Ätiologie der VAA werden angeborene oder arteriosklerotische Faktoren, Mediadefekte, Infektionen, Vaskulitiden oder Traumata diskutiert. Ultraschall, Computertomographie und Magnetresonanztomographie erlauben die Diagnose der VAA. Die niedrige perioperative Mortalität bei gleichzeitig exzellenten Langzeitergebnissen rechtfertigt die prophylaktische Therapie auch asymptomatischer VAA, da die Mortalität rupturierter VAA fast 100% beträgt. Die radiologisch-interventionelle Vorgehensweise sollte einem selektionierten Patientengut vorbehalten bleiben und hat sich auch in neueren Studien noch nicht als überlegen erwiesen.
Severe obstructive calcifications affecting the descending and suprarenal abdominal aorta without coexisting peripheral atherosclerotic disease – coral reef aorta
Authors: Teebken  , Pichlmaier  , Kühn  , Haverich
Published: September 2006

The case of a 58-year-old woman with leg claudication due to a very rare form of atherosclerosis affecting the descending thoracic and abdominal aorta – known as coral reef aorta – without involvement of the femoro-distal vessels is reported. The patient was treated with a polyester bifurcation graft from the proximal descending aorta to both common iliac arteries via a left dorsal minithoracotomy and a second left retroperitoneal approach. This unusual approach was chosen instead of direct aortic replacement in order to prevent paraplegia. In case of future visceral or left renal malperfusion the diseased artery can be connected to the prosthesis directly or by the use of an additional bypass graft. This would not be the case with a conventional axillo-bifemoral graft.
Two cases of buttock claudication caused by isolated internal iliac artery stenosis
Authors: Kahle  , Schmidt-Lucke
Published: September 2006

We present two cases of buttock claudication caused by severe stenosis of the internal iliac artery which disappeared totally after percutaneous transluminal angioplasty (PTA). Isolated stenoses of internal iliac arteries are rare. It is often difficult to distinguish between vascular buttock claudication and neurological or orthopaedic symptoms. Conventional or MR-angiography is necessary to secure the diagnosis. PTA of internal iliac artery stenosis is the adequate treatment.
Standardtherapie der chronischen Hepatitis B
Authors: Thimme  , Blum
Published: September 2006

Weltweit sind ungefähr 350 Millionen Personen mit Hepatitis-B-Virus infiziert, von denen eine halbe bis eine Million jedes Jahr an den Folgen der Lebererkrankung sterben. Das Behandlungsziel liegt darin, ein Fortschreiten der Lebererkrankung zur Leberzirrhose und zum hepatozellulären Karzinom zu vermeiden. In den letzten zehn Jahren ist ein deutlicher Fortschritt in der Behandlung der chronischen Hepatitis B erreicht worden. Für die Therapie stehen derzeit Inferferon-alpha, Lamivudine und Adefovir zur Verfügung. Die Wirksamkeit der verschiedenen antiviralen Substanzen wird von viralen und klinischen Faktoren beeinflusst, die bei der Therapieplanung berücksichtigt werden müssen und im Folgenden dargestellt werden.
Gently dipping fracture zones in Paleoproterozoic metagranite, Sweden: Evidence from reflection seismic and cored borehole data and implications for the disposal of nuclear waste
Authors: Juhlin Christopher , Stephens Michael B.
Published: September 2006

The Svecokarelian orogen in the coastal area north of Stockholm, central Sweden, is characterized by a complex deformation belt. In this belt, bedrock domains strike WNW‐NW, dip steeply, and are affected by high ductile strain. These domains anastomose around tectonic lenses that are up to a few tens of kilometers in length and are a few kilometers wide. The bedrock within the lenses is folded and, in general, affected by lower ductile strain. Site investigations for the disposal of highly radioactive nuclear waste are presently in progress within one of these lenses. Approximately 16 km of high‐resolution (10 m source and receiver spacing, 100 channels) seismic data were acquired in 2002 along five separate profiles (2 to 5 km in length) within this lens. In the southeast, reflection orientations are well determined where profiles cross one another. Here, there is a nearly one to one correlation of distinct reflections on the seismic sections with hydraulically conductive fracture zones in cored boreholes, indicating that these fracture zones control the reflectivity. However, smaller lenses of amphibolite within the fracture zones may enhance the reflectivity. The reflections dip gently to the SSE and SE, and the zones in the boreholes are dominated by fractures that show the same dip direction or are subhorizontal. A working hypothesis for the gently dipping fracture zones suggests that these structures formed as minor thrust faults during the later stages of the Svecokarelian orogeny. Mineral fillings and coatings along fractures in these zones indicate later reactivation. The current stress field, a high intensity of fractures in the zones at a high angle to σ3, high in situ stresses in the bedrock, and rapid glacial unloading with the development of high differential stresses may explain the large volume of groundwater in these zones. The reflection seismic data, in combination with the verifying work presented in the cored borehole data, have steered the subsequent focus in geoscientific studies to the northwestern part of the candidate area.
Diagenesis of deformation band faults: Record and mechanical consequences of vadose zone flow and transport in the Bandelier Tuff, Los Alamos, New Mexico
Authors: Wilson Jennifer E. , Goodwin Laurel B. , Lewis Claudia
Published: September 2006

Deformation band faults in nonwelded ignimbrites of the Bandelier Tuff record unsaturated fluid flow and transport. More than two thirds of the faults studied display diagenetic minerals virtually absent from adjacent protolith. Stable isotope analyses indicate that smectite enrichment and calcite cementation result from low‐temperature meteoric fluid‐fault interaction. Fault zone microstructures, rare earth element signatures, and mineralogy indicate that smectite was introduced to deformation band fault zones by a combination of translocation from the surface and in situ alteration of fault gouge. Rod‐shaped calcite microcrystallites and the close association of calcite with plant roots suggest a combination of pedogenic, biologically mediated, and physicochemical precipitation. Enrichment in smectite and calcite modified major oxide and trace element contents of deformation bands with respect to protolith. Collectively, these observations indicate that these faults have served as, and may still be, zones of preferential vadose zone fluid flow and transport. These processes alter fault rock permeability; affect the transport of solutes via processes such as dissolution, precipitation, and adsorption, and they change the mechanical properties of the fault zone. Smectite and calcite enrichment results in localization of deformation, effectively halting the further development of deformation bands. Vadose zone alteration therefore is one way to produce a clay‐rich fault core at early stages in a fault's history, resulting in fault zone weakening and localization of slip. Progressive burial of growth faults can subsequently bring fault cores into the seismogenic zone.
Seasonal and interannual global surface mass variations from multisatellite geodetic data
Authors: Wu Xiaoping , Heflin Michael B. , Ivins Erik R. , Fukumori Ichiro
Published: September 2006

Monthly global surface mass distribution changes are estimated in the spherical harmonic domain with a complete spectrum up to degree and order 50. The estimates are derived by inverting GPS displacement series measured at roughly 450 continuously tracking sites and ocean bottom pressure (OBP) estimates of a data assimilated ocean circulation model from 1993 to 2004. The inversion uses a hybrid estimator after singular value decomposition of the normalized measurement equations with reduced reliance on a priori spectral information. The results are then compared and combined with Gravity Recovery and Climate Experiment (GRACE) gravity data to provide enhanced spectral and geographic coverage. High fidelity degree‐1 surface mass variation coefficients are recovered, corresponding to equivalent geocenter motion with better than 0.5 mm annual amplitude precisions in all three components. A clear annual surface mass cycle occurs in both GPS/OBP‐ and GRACE‐derived results. There is very good agreement among the low‐degree spherical harmonic coefficients and in global geographic pattern but with significant regional differences in amplitudes. Annual variations of average mass over the global oceans, Antarctica, and Greenland are then derived. Total surface mass over both Antarctica and Greenland peak in their respective summers due to increased atmospheric mass. Large interannual variations have also been found involving several continents in the 11‐year GPS/OBP solution. The patterns of variation suggest that the recent satellite laser ranging (SLR) observation of a reversal in trend of the Earth's oblateness may be largely an interannual surface mass cycle with considerable contribution from the northern continents.
New models for satellite altimeter sea state bias correction developed using global wave model data
Authors: Tran N. , Vandemark D. , Chapron B. , Labroue S. , Feng H. , Beckley B. , Vincent P.
Published: September 2006

Changing surface wave conditions alter the altimeter's estimate of mean sea level. Present‐day methods for correcting this bias are solely based on wave and wind information from the altimeter. This paper tests the use of additional information to develop several sea state bias correction models using a yearlong combination of Jason‐1 data with wave field statistics generated from the WaveWatch3 ocean wave model hindcast. Each candidate model is produced in the same manner, using a nonparametric mapping between Jason‐1 sea surface height anomaly estimates and two correlatives. The first is always the significant wave height from Jason‐1 and the model differences come through choice of the second variable. Past studies dictate our selection of these second parameters and they include terms related to the local wind speed, swell energy, wave age, wave period, and wave slope. Model skills are evaluated in terms of explained variance. Several models indicate promise for wave model use in future empirical developments. For instance, results show that in the low latitudes the models developed using the swell height and mean period modestly but systematically outperform the actual operational parameterisation. This study further indicates that systematic regional error in the present sea level corrections may be improved by inclusion of wave model information.
Extreme longitudinal variability of plasma structuring in the equatorial ionosphere on a magnetically quiet equinoctial day
Authors: McDonald Sarah E. , Basu Sunanda , Basu Santimay , Groves Keith M. , Valladares Cesar E. , Scherliess Ludger , Thompson Donald C. , Schunk Robert W. , Sojka Jan J. , Zhu Lie
Published: September 2006

We investigate the extreme longitudinal variability of equatorial scintillation under quiet magnetic conditions during 22–23 March 2002. Scintillation Network Decision Aid (SCINDA) observations show intense activity in the South American–Atlantic sector during local evening hours, whereas an absence of scintillation is seen in the far east Asian sector. Ground‐ and space‐based measurements from SCINDA, the Global Ultraviolet Imager (GUVI), TOPEX, and a chain of GPS receivers are used in combination with the Utah State University Global Assimilation of Ionospheric Measurements (USU‐GAIM) model to explore the relationship between the large‐scale ionization distribution and small‐scale irregularities at low latitudes in both the scintillating and nonscintillating longitude sectors. Our analysis shows that there are significant differences in the evolution of the ionization distributions during the evening hours, which are likely the result of differences in the daytime and postsunset vertical plasma drift in the two sectors. This study demonstrates the importance of USU‐GAIM as a new tool for investigating longitudinal as well as day‐to‐day variability that is observed in the large‐scale distribution of the ionosphere and how this relates to the occurrence of scintillation.
Space weather drivers in the ACE era
Authors: Vogt Marissa F. , Cohen Christina M. S. , Puhl‐Quinn Pamela , Jordanova Vania K. , Smith Charles W. , Skoug Ruth M.
Published: September 2006

We examine ACE observations of interplanetary disturbances and energetic particle activity for the period of solar maximum during solar cycle 23 and compare these measurements to the historical record as represented by the National Space Science Data Center Omnitape of near‐Earth observations. Magnetospheric response parameters, Dst and Kp, are similarly compared for the two epochs. We find that ACE observed an unexpectedly large number of the strongest transient events with the strength of magnetospheric drivers exceeding the historical record for the space flight era. This is not entirely true of the magnetospheric response, which demonstrates that the magnetospheric response is an integrated effect that is more subtle than examination of single hourly averages would indicate. For these and other reasons, we argue that satellites at L1 orbit, such as ACE, provide an excellent database for the study of magnetospheric storm drivers and their associated energetic particle populations from which space weather models may be refined. We also compare and contrast energetic particle measurements. While protons are a large space weather concern, heavy ions are also a radiation hazard for hardware in particular. We argue that heavy ion radiation predictions based on the measurements of protons are not reliable and that only by measuring the actual composition of the solar energetic particle population can we hope to understand and address the threat posed by these particles to machines and to obtain a more complete view of the radiation environment.
Intermediate level Lagrangian subsurface measurements in the northeast Pacific: Isobaric RAFOS float data
Authors: Margolina Tetyana , Collins Curtis A. , Rago Thomas A. , Paquette Robert G. , Garfield Newell
Published: September 2006

Isobaric RAFOS floats have been used to track the California Undercurrent and to investigate its continuity since 1992. The data include 61 quasi‐Lagrangian subsurface trajectories sampled for the most part between 150 and 600 m. The data set allows estimates of Eulerian and Lagrangian statistics for the region, studies of mesoscale eddy activity, and analysis of seasonal variability of circulation patterns off Central California. A browsable Web‐based inventory and a Graphical User Interface have been developed to provide access to this data set, including interactive manipulation of the data.
Electric field transition between the diffuse and streamer regions of sprites estimated from ISUAL/array photometer measurements
Authors: Adachi T. , Fukunishi H. , Takahashi Y. , Hiraki Y. , Hsu R.‐R. , Su H.‐T. , Chen A. B. , Mende S. B. , Frey H. U. , Lee L. C.
Published: September 2006

We analyze optical data of twenty sprites and three halos observed by the array photometer which is a scientific instrument of the ISUAL payload on the FORMOSAT‐2 satellite. The altitude distribution of electric field is derived from the ratio of blue to red emission intensity by assuming all emissions are due to the electron impact excitation of nitrogen molecules. We find a clear transition at ∼75 km altitude from the upper‐diffuse to lower‐streamer region. Estimated electric field intensities in the diffuse region are 0.5–0.7 Ek, which support the theoretical expectation that their optical emissions could be produced without significant ionization. On the other hand, those in the streamer region are 1–2 Ek which is a few times less than predicted fields in the streamer head. We suggest that this discrepancy is due to the long‐lasting components such as the lower portions of the upward branches and bead structures.
Effects of cirrus near the tropopause on anvil cirrus dynamics
Authors: Garrett T. J. , Zulauf M. A. , Krueger S. K.
Published: September 2006

Recent space and airborne observations have noted tenuous cirrus near the tropopause and above deep convective anvil outflow. We use a cloud‐resolving model, initialized with aircraft observations taken during the CRYSTAL‐FACE experiment, to explore the effects of such cirrus layers on anvil evolution. Numerical simulations demonstrate that anvil cirrus spreads because strong absorption of thermal radiation and emission at cloud base and top creates horizontal heating gradients between the cloud and its environment. The presence of a second layer of cirrus near the tropopause forces the upper part of the anvil to equilibrate to warmer radiative temperatures than would normally be associated with a clear upper atmosphere. Compared to a case without thin cirrus, the associated reduction to heating gradients at anvil cloud top corresponds to reduced anvil spreading and turbulent kinetic energy, by as much as 19% and 40%, respectively. These results suggest that tropopause cirrus can affect climate indirectly, by altering anvil cirrus dynamics.
Hybrid simulations of parallel and oblique electromagnetic alpha/proton instabilities in the solar wind
Authors: Lu Q. M. , Xia L. D. , Wang S.
Published: September 2006

The linear Vlasov theory has shown that the relative flow between alpha particles and protons in the fast solar wind can excite both magnetosonic and oblique Alfven modes and the velocity threshold of the Alfven instability is lower than that of the magnetosonic instability. In this paper, hybrid simulations are performed to investigate the nonlinear evolution of parallel and oblique electromagnetic alpha/proton instabilities in the fast solar wind. The parallel proton plasma beta, defined as β∥p = 8πnpkBT∥p/B02, is set equal to 0.15, and the initial average value of the alpha/proton relative flow speed is chosen as 1.76vA (vA is the local Alfven speed). The influences of the temperature anisotropy of alpha particles (T⊥α/T∥α) and temperature anisotropy of protons (T⊥p/T∥p) on the alpha/proton instabilities are also considered. The decrease of the temperature anisotropy of alpha particles (T⊥α/T∥α) can significantly enhance the amplitude of both the magnetosonic and oblique Alfven modes and decelerate alpha particles more efficiently, while the temperature anisotropy of protons (T⊥p/T∥p) tends to reduce the amplitudes of these two modes. Moreover, in the two‐dimensional hybrid simulations the magnetosonic waves are first excited. Then the oblique Alfven waves are also excited and dominate the wave spectrum at the late stage of time evolution. The implications of our simulation results on observations in the fast solar wind are also discussed.
Direct observation and reactions of Cl3 radical
Authors: Enami Shinichi , Yamanaka Takashi , Hashimoto Satoshi , Kawasaki Masahiro , Aloisio Simone , Tachikawa Hiroto
Published: October 2006

The broad absorption of Cl3 radical was observed between 1150 and 1350nm using cavity ring-down spectroscopy at 213–265K and 50–200Torr with He, N2, Ar, or SF6 diluents. The absorption intensity of Cl3 increased at lower temperature and higher pressure. SF6 was the most efficient diluent gas. The temperature dependent equilibrium constants for Cl3 formation from Cl+Cl2 were theoretically calculated at the MP4SDQ∕6-311+G(d) level. Observed decay time profiles of Cl3 and the pressure dependence of Cl3 formation are explained by the equilibrium reaction and a decay reaction of Cl+Cl3.
Evaporative cooling in microfluidic channels
Authors: Maltezos George , Rajagopal Aditya , Scherer Axel
Published: September 2006

Evaporative cooling is an effective and energy efficient way to rapidly remove heat from a system. Specifically, evaporative cooling in microfluidic channels can provide a cost-effective solution for the cooling of electronic devices and chemical reactors. Here we present microfluidic devices fabricated by using soft-lithography techniques to form simple fluidic junctions between channels carrying refrigerant and channels carrying N2 gas. The effects of channel geometry and delivery pressure on the performance of refrigeration through vaporization of acetone, isopropyl alcohol, and ethyl ether were characterized. By varying gas inlet pressures, refrigerants, and angles of the microfluidic junctions, optimal cooling conditions were found. Refrigeration rates in excess of 40°C∕s were measured, and long lasting subzero cooling in the junction could be observed.
Calculating vibrational energies and wave functions of vinylidene using a contracted basis with a locally reorthogonalized coupled two-term Lanczos eigensolver
Authors: Tremblay Jean Christophe , Carrington Tucker
Published: September 2006

We use a contracted basis+Lanczos eigensolver approach to compute vinylidene-like vibrational states of the acetylene-vinylidene system. To overcome problems caused by loss of orthogonality of the Lanczos vectors we reorthogonalize Lanczos vector and use a coupled two-term approach. The calculations are done in CC–HH diatom-diatom Jacobi coordinates which make it easy to compute states one irreducible representation at a time. The most costly parts of the calculation are parallelized and scale well. We estimate that the vinylidene energies we compute are converged to ∼1cm−1.
Laser emission from GaN photonic crystals
Authors: Chang Li-Ming , Hou Chia-Hung , Ting Yu-Chen , Chen Chii-Chang , Hsu Che-Lung , Chang Jenq-Yang , Lee Chien-Chieh , Chen Guan-Ting , Chyi Jen-Inn
Published: September 2006

In this study, photonic crystals have been designed, fabricated, and characterized in GaN bulk materials. The energy dependent measurement showed that the emission peak width can be significantly reduced as the pumping pulse energy was larger than 0.7μJ at room temperature. The mode at the wavelength of 371nm emitted from the defect due to the structure disorder unintentionally introduced during the fabrication process of the GaN photonic crystals can be obtained.
Ice-surface adsorption enhanced colligative effect of antifreeze proteins in ice growth inhibition
Authors: Mao Yougang , Ba Yong
Published: September 2006

This Communication describes a mechanism to explain antifreeze protein’s function to inhibit the growth of ice crystals. We propose that the adsorption of antifreeze protein (AFP) molecules on an ice surface induces a dense AFP-water layer, which can significantly decrease the mole fraction of the interfacial water and, thus, lower the temperature for a seed ice crystal to grow in a super-cooled AFP solution. This mechanism can also explain the nearly unchanged melting point for the ice crystal due to the AFP’s ice-surface adsorption. A mathematical model combining the Langmuir theory of adsorption and the colligative effect of thermodynamics has been proposed to find the equilibrium constants of the ice-surface adsorptions, and the interfacial concentrations of AFPs through fitting the theoretical curves to the experimental thermal hysteresis data. This model has been demonstrated by using the experimental data of serial size-mutated beetle Tenebrio molitor (Tm) AFPs. It was found that the AFP’s ice-surface adsorptions could increase the interfacial AFP’s concentrations by 3 to 4 orders compared with those in the bulk AFP solutions.
Carrier lifetime reduction in 1.5μm AlGaAsSb saturable absorbers with air and AlAsSb barriers
Authors: Ostinelli O. , Bächtold W. , Haiml H. , Grange R. , Keller U. , Gini E. , Almuneau G.
Published: September 2006

The optical properties of different AlGaAsSb semiconductor saturable absorber mirrors and InP∕AlGaAsSb heterostructures have been investigated by pump-probe and low temperature photoluminescence measurements. The results show that the type-II electron-hole recombination process at the InP–AlGaAsSb interface is responsible for the slow carrier decay time in the absorber. Nevertheless, this slow transition can be avoided by growing an AlAsSb barrier layer between InP and the absorber layer promoting the fast electron-hole recombination at the surface states on the absorber/air interface. This allows reducing the carrier decay time from several nanoseconds down to 20ps.
Radiation damage to DNA: Electron scattering from the backbone subunits
Authors: Tonzani Stefano , Greene Chris H.
Published: September 2006

In the context of damage to DNA by low energy electrons, we carry out calculations of electron scattering from tetrahydrofuran and phosphoric acid, models of the subunits in the DNA backbone, as a first step in simulating the electron capture process that occurs in the cell. In the case of tetrahydrofuran, we also compare with previous theoretical and experimental data. A comparison of the shape of the resonant structures to virtual orbitals is also performed to gain insight into the systematic connections with electron scattering from similar molecules and dissociative electron attachment experiments.
Probing of the electric field distribution in organic field effect transistor channel by microscopic second-harmonic generation
Authors: Manaka Takaaki , Lim Eunju , Tamura Ryosuke , Yamada Daisuke , Iwamoto Mitsumasa
Published: September 2006

Electric field distribution in channel of pentacene field effect transistor (FET) was successfully probed by microscopic optical second-harmonic generation (SHG) observation. Microspot SHG signals were acquired at various points in the channel with scanning a spot position along source-drain direction. For the FET at off state, enhanced SHG signal was observed, indicating the Laplace field formation reflecting the device geometry. This clearly supports the insulating nature of pentacene layer at off state. After turning on the FET, SHG profile changed drastically, indicating change in the field distribution by the space charge formation in the channel due to the carrier injection.
Photostimulated luminescence from BaCl2:Eu2+ nanocrystals in lithium borate glasses following neutron irradiation
Authors: Appleby G. A. , Edgar A. , Williams G. V. M. , Bos A. J. J.
Published: September 2006

A glass-ceramic thermal neutron imaging plate material is reported. The material consists of a neutron sensitive 2B2O3–Li2O glass matrix containing nanocrystallites of the storage phosphor BaCl2:Eu2+. When doped with 0.5mol% Eu2+, the neutron induced photostimulated luminescence (PSL) conversion efficiency of the B10 enriched glass-ceramic is around 60% of that a commercial neutron imaging plate, while the γ sensitivity is an order of magnitude lower than that of the commercial plate. A Eu2+-concentration series shows that the PSL efficiency for x rays is optimized at 0.01mol% Eu2+. Thermoluminescence measurements indicate trap depths in BaCl2:Eu2+ ranging from 0.55to2.7eV.
Lasing of wavelength-tunable (1.55μm region) InAs∕InGaAsP∕InP (100) quantum dots grown by metal organic vapor-phase epitaxy
Authors: Anantathanasarn S. , Nötzel R. , van Veldhoven P. J. , van Otten F. W. M. , Barbarin Y. , Servanton G. , de Vries T. , Smalbrugge E. , Geluk E. J. , Eijkemans T. J. , Bente E. A. J. M. , Oei Y. S. , Smit M. K. , Wolter J. H.
Published: September 2006

The authors report lasing of InAs∕InGaAsP∕InP (100) quantum dots (QDs) wavelength tuned into the 1.55μm telecom region. Wavelength control of the InAs QDs in an InGaAsP∕InP waveguide is based on the suppression of As∕P exchange through ultrathin GaAs interlayers. The narrow ridge-waveguide QD lasers operate in continuous wave mode at room temperature on the QD ground state transition. The low threshold current density of 580A∕cm2 and low transparency current density of 6A∕cm2 per QD layer, measured in pulsed mode, are accompanied by low loss and high gain with an 80-nm-wide gain spectrum.
Photodissociation of Mg+–XCH3 (X=F, Cl, Br, and I) complexes. I. Electronic spectra and dissociation pathways
Authors: Furuya Ari , Misaizu Fuminori , Ohno Koichi
Published: September 2006

Photodissociation spectra of Mg+–XCH3 (X=F, Cl, Br, and I) complexes have been measured in the ultraviolet region (225–415nm). Several fragment ions with and without charge transfer (CT), Mg+, XCH3+, MgX+, MgCH3+, CH3+, and X+, were formed by evaporation (intermolecular bond dissociation) and intracluster reaction (intramolecular bond dissociation) via excited electronic states. Branching ratios of these ions were found to depend both on absorption bands and on halogen atoms. The ground states of the complexes were calculated to have geometries in which the Mg atom lies next to X atom of methyl halide molecules. Positive charges of the complexes are confirmed to be almost localized on Mg. Observed absorption bands were assigned to the transitions of the Mg+P2-S2 atomic line perturbed by interactions with methyl halide molecules. Branching ratios of fragment ions can be partly explained by the stability of fragment ions and neutral counterparts. From the excited state potential energy curves along the Mg–X bond distance, dissociation reaction after CT was concluded to proceed predissociatively; potential curve crossings between the initially excited states and repulsive CT states may have a crucial role in the formation of CH3+, XCH3+, and X+. In particular, XCH3+ ions were formed via repulsive CT states having a character of electron excitation from Xnp to Mg+3s.
Sterilization mechanism for Escherichia coli by plasma flow at atmospheric pressure
Authors: Sato Takehiko , Miyahara Takashi , Doi Akiko , Ochiai Shiroh , Urayama Takuya , Nakatani Tatsuyuki
Published: September 2006

A mechanism for sterilizing Escherichia coli by a flowing postdischarge and UV radiation of argon plasma at atmospheric pressure was investigated by analyzing the surviving cells and the potassium leakage of cytoplasmic material and by morphological observation. Inactivation of E. coli results from the destruction of the cytoplasmic membrane and the outer membrane under plasma exposure and the destruction of nucleic acids by exposure to ultraviolet radiation from the plasma source.
Q
-controlled amplitude modulation atomic force microscopy in liquids: An analysis
Authors: Hölscher H. , Schwarz U. D.
Published: September 2006

An analysis of amplitude modulation atomic force microscopy in liquids is presented with respect to the application of the Q-Control technique. The equation of motion is solved by numerical and analytic methods with and without Q-Control in the presence of a simple model interaction force adequate for many liquid environments. In addition, the authors give an explicit analytical formula for the tip-sample indentation showing that higher Q factors reduce the tip-sample force. It is found that Q-Control suppresses unwanted deformations of the sample surface, leading to the enhanced image quality reported in several experimental studies.
High bandwidth Ge p-i-n photodetector integrated on Si
Authors: Oehme M. , Werner J. , Kasper E. , Jutzi M. , Berroth M.
Published: September 2006

The authors present a germanium on silicon p-i-n photodiode for vertical light incidence. For a Ge p-i-n photodetector with a radius of 5μm a 3dB bandwidth of 25GHz is measured at an incident wavelength of 1.55μm and zero external bias. For a modest reverse bias of 2V, the 3dB bandwidth increases to 39GHz. The monolithically integrated devices are grown on Si with solid source molecular beam epitaxy. The complete detector structure consisting of a highly p-doped Ge buried layer, an intrinsic absorption region, and a highly n-doped top contact layer of Ge∕Si is grown in one continuous epitaxial run. A low growth temperature sequence was needed to obtain abrupt doping transitions between the highly doped regions surrounding the intrinsic layer. A theoretical consideration of the 3dB bandwidth of the Ge detector was used to optimize the layer structure. For a photodiode with 5μm mesa radius the maximum theoretical 3dB frequency is 62GHz with an intrinsic region thickness of 307nm.
Uncooled infrared imaging using bimaterial microcantilever arrays
Authors: Grbovic D. , Lavrik N. V. , Datskos P. G. , Forrai D. , Nelson E. , Devitt J. , McIntyre B.
Published: September 2006

We report on fabrication and characterization of arrays of bimaterial microcantilevers and discuss their performance as uncooled infrared imagers. An optical readout was used to simultaneously measure deflections of all microcantilevers in the array. The fabricated arrays had an average noise equivalent temperature difference (NETD) and a response time of 1.5K and 6ms, respectively. Some microcantilevers in the array exhibited NETD values below 500mK, approaching our theoretical prediction of 151mK. A unique and valuable feature of the implemented approach is its straightforward scalability to higher resolution arrays, without progressively growing complexity and cost.