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Three novel nonenzymatic sensors based on the modification of a glassy carbon electrode with nanoparticles of Fe3+, Cu2+, or Ni2+ Prussian blue (PB) derivatives are proposed herein. The Fe3+-, Cu2+-, and Ni2+-modified PB nanoparticles were supported in an environmentally friendly chemical product known as melanin. The nanomaterials prepared were characterized by transmission electron microscopy images, electrochemical impedance spectroscopy, and cyclic voltammetry. The drop casting method was used to build the enzymeless sensors, which were able to catalyze the oxidation of hydrogen peroxide (H2O2) at +1.5 V. The calibration curves obtained by amperometry were linear in the range of 0.1–13 mmol $\text{L}^{-1}$ . Several figures of merit were obtained in order to characterize the analytical electrochemical behavior of the as-prepared sensors. For instance, the detection limits achieved were 0.14, 0.32, and 0.57 $\mu $ mol $\text{L}^{-1}$ for the melanin-capped modified PB nanoparticle sensor containing, respectively, Fe3+, Cu2+, and Ni2+ ions. These values are lower than the detection limits provided by other nonenzymatic sensors. The sensors were applied for the detection of H2O2 in tooth whitening gel. The results obtained were compared with those of the standard method.

Biological invasions of non-native species are an important conservation issue because of the potential negative impacts on native plant and animal communities. One species of concern in Virginia is Japanese spiraea (Spiraea japonica L.f.). At Buffalo Mountain Natural Area Preserve (BMNAP) the spread of Japanese spiraea threatens the integrity of native high-elevation grassy balds, eastern redcedar (Juniperus virginiana L.) glades, and mafic seep communities. A prerequisite to successful management of a non-native species is knowledge about where a species has established and how it spreads. Thus, our objectives were to: (1) identify current populations of Japanese spiraea at BMNAP, and (2) characterize environmental conditions favoring the growth of Japanese spiraea. Paired-plot sampling was used to compare environmental parameters from adjacent plots with and without Japanese spiraea. Canopy cover was significantly lower in plots with Japanese spiraea compared to plots without Japanese spiraea (t = 1.76, P = 0.02), suggesting Japanese spiraea is more successful in establishing in higher light environments. At BMNAP, lower canopy cover reflected historical disturbances such as old power line cuts or roads. Although Japanese spiraea is not currently invading the grassy balds or eastern redcedar glades at the Buffalo Mountain summit, existing populations pose an immediate threat to the mafic seeps at the base of the mountain. Regular monitoring and mapping will be important to prevent Japanese spiraea from hindering conservation goals.

In this paper, we report results on two-colour above-threshold ionisation, where extreme ultraviolet pulses of femtosecond duration were synchronised to intense infrared laser pulses of picosecond duration, in order to study the laser-assisted photoelectric effect of atomic helium, neon, krypton and xenon which leads to the appearance of characteristic sidebands in the photoelectron spectra. The observed trends are found to be well described by a simple model based on the soft-photon approximation, at least for the relatively low optical intensities of up to 5x10$^{11}$ Wcm$^{-2}$ employed in these early experiments.

Citation frequency is often used in hiring and tenure decisions as an indicator of the quality of a researcher's publications. In this paper, we examine the influence of discipline, institution, journal impact factor, length of article, number of authors, seniority of author, and gender on citation rate of top-cited papers for academic faculty in geography and forestry departments. Self-citation practices and patterns of citation frequency across post-publication lifespan were also examined. Citation rates of the most-highly cited paper for all tenured forestry (N = 122) and geography (N = 91) faculty at Auburn University, Michigan State University, Northern Arizona University, Oklahoma State University, Pennsylvania State University, Texas A&M University, University of Florida, University of Massachusetts, University of Washington, and Virginia Tech were compared. Foresters received significantly more citations than geographers (t = 2.46, P = 0.02) and more senior authors received more citations than junior researchers (r 2 = 0.14, P = 0.03). Articles published in journals with higher impact factors also received more citations (r 2 = 0.28, P = 0.00). The median self-citation rate was 10% and there was no temporal pattern to the frequency of citations received by an individual article (x 2 = 176). Our results stress the importance of only comparing citation rates within a given discipline and confirm the importance of author-seniority and journal rankings as factors that influence citation rate of a given article.

A non-immune library of human single chain fragment variable (scFv) antibodies displayed on Sacchar- omyces cerevisiae was screened for binding to the Clostridium botulinum neurotoxin serotype A binding domain (BoNT/A (Hc)) with the goal of identifying scFv to novel epitopes. To do this, an antibody-mediated labeling strategy was used in which antigen-binding yeast clones were selected after label- ing with previously characterized monoclonal antibodies (MAbs) specific to the Hc. Twenty unique scFv clones were isolated that bound Hc. Of these, 3 also bound to full-length BoNT/A toxin complex with affinities ranging from 5 to 48 nM. Epitope binning showed that the three unique clones recognized at least two epitopes distinct from one another as well as from the detection MAbs. After production in E. coli, scFv were coupled to magnetic particles and tested for their ability to capture BoNT/A holotoxin using an Endopep-MS assay. In this assay, toxin captured by scFv coated magnetic particles was detected by incubation of the complex with a peptide containing a BoNT/A-specific cleavage sequence. Mass spectrometry was used to detect the ratio of intact peptide to cleavage products as evidence for toxin capture. When tested individually, each of the scFv showed a weak positive Endopep-MS result. However, when the particles were coated with all three scFv simultaneously, they exhib- ited significantly higher Endopep-MS activity, consistent with synergistic binding. These results demonstrate novel approaches toward the isolation and characterization of scFv antibodies specific to unlabeled antigens. They also provide evidence that distinct scFv antibodies can work synergisti- cally to increase the efficiency of antigen capture onto a solid support. Biotechnol. Bioeng. 2011;108: 2456-2467.

During the last few years Europe has made enormous progress towards free electron laser (FEL)-based research infrastructures. The FLASH facility [1] at DESY in Hamburg, Germany, has been in user operation since the summer of 2005; FERMI@Elettra [2] in Trieste, Italy, is under construction; the European XFEL [3] in Hamburg will start construction in summer 2008; and several other FEL projects are being prepared in France, Germany, Italy, Poland, Sweden, Switzerland and the UK. In addition, a number of dedicated test facilities have become available, including the photo-injector test facility (PITZ) [4] and the cryomodule test bench (CMTB) [5] at DESY, the HoBiCaT facility for testing superconducting cavities [6] at BESSY, Berlin, Germany, the SPARC facility [7] at INFN-LNF in Frascati, Italy, and the ERL Prototype (ERLP) [8] at Daresbury Laboratory, UK. They have been strongly supported by the national stakeholders in order to prepare the design of new FEL sources.

We describe herein a novel type of monodisperse water-soluble magnetite nanoparticle coated with pheomelanin using an environmentally-friendly approach in aqueous medium. The results indicate superparamagnetic behaviour at room temperature and show improved negative contrast in T2-weighted MRI with a transverse relaxivity of 218 mM(-1) s(-1).

Two new synthetic melanin-like oligomers inspired by the synthesis of pheomelanin (cys-DOPA) were prepared using L-DOPA as a precursor and the amino acids serine (ser-DOPA) and threonine (thr-DOPA) for modifications. The products obtained exhibited appreciable antioxidant activity. The compounds were characterized by liquid chromatography-mass spectrometry (LC-MS), elemental analysis and infrared spectroscopy. The pKa values of the groups present in each melanin suspension were determined in aqueous solution by potentiometric and spectrophotometric titration. Cytotoxicity assays showed an IC50 > 500 mg L -1 resulting in non-toxic compounds for living cells. Finally, cys-DOPA, ser-DOPA and thr-DOPA exhibited antioxidant activity determined by the DPPH scavenging assay, with EC50 = 7.69, 1.02 and 27.60 mg L -1 , respectively.

FLASH at DESY in Hamburg, the first and currently only free-electron laser for VUV and soft X-ray radiation, started user operation in the summer of 2005. Currently it covers a wavelength range from 13 nm to 50 nm with GW peak power and pulse durations between 10 fs and 50 fs. Approximately 20 weeks of beamtime are provided per year for scientific experiments that are not possible on any other radiation source.

Yeast display is a powerful tool for increasing the affinity and thermal stability of scFv antibodies through directed evolution. Mammalian calmodulin (CaM) is a highly conserved signaling protein that undergoes structural changes upon Ca 2 + binding. In an attempt to generate conformation-specific antibodies for proteomic applications, a selection against CaM was undertaken. Flow cytometry-based screening strategies to isolate easily scFv recognizing CaM in either the Ca 2 + -bound (Ca 2 + -CaM) or Ca 2 + -free (apo-CaM) states are presented. Both full-length scFv and single-domain VH only clones were isolated. One scFv clone having very high affinity (K d = 0.8 nM) and specificity (>1000-fold) for Ca 2 + -CaM was obtained from de novo selections. Subsequent directed evolution allowed the development of antibodies with higher affinity (K d = 1 nM) and specificity (>300-fold) for apo-CaM from a parental single-domain clone with both a modest affinity and specificity for that particular isoform. CaM-binding activity was unexpectedly lost upon conversion of both conformation-specific clones into soluble fragments. However, these results demonstrate that conformation-specific antibodies can be quickly and easily isolated by directed evolution using the yeast display platform.

Botulism is caused by botulinum neurotoxin (BoNT), the most poisonous substance known. Potential use of BoNT as a biothreat agent has made development of sensitive assays for toxin detection and potent antitoxin for treatment of intoxication a high priority. To improve detection and treatment of botulism, molecular evolution and yeast display were used to increase the affinity of two neutralizing single chain Fv (scFv) antibodies binding BoNT serotype A (BoNT/A). Selection of yeast displayed scFv libraries was performed using methods to select for both increased association rate constant (k(on)) and decreased dissociation rate constants (k(off)). A single cycle of error prone mutagenesis increased the affinity of the 3D12 scFv 45-fold from a K(D) of 9.43x10(-10)M to a K(D) of 2.1x10(-11)M. Affinity of the HuC25 scFv was increased 37-fold from 8.44x10(-10)M to 2.26x10(-11)M using libraries constructed by both random and site directed mutagenesis. scFv variable region genes were used to construct IgG for use in detection assays and in vivo neutralization studies. While IgG had the same relative increases in affinity as scFv, (35-fold and 81-fold, respectively, for 3D12 and HuC25) higher solution equilibrium binding constants were observed for the IgG, with the 3D12 K(D) increasing from 6.07x10(-11)M to 1.71x10(-12)M and the HuC25 K(D) increasing from 4.51x10(-11)M to 5.54x10(-13)M. Affinity increased due to both an increase in k(on), as well as slowing of k(off). Higher affinity antibodies had increased sensitivity, allowing detection of BoNT/A at concentrations as low as 1x10(-13)M. The antibodies will also allow testing of the role of affinity in in vivo toxin neutralization and could lead to the generation of more potent antitoxin.

In a free-electron laser (FEL) the lasing medium is a high-energy beam of electrons flying with relativistic speed through a periodic magnetic field. The interaction between the synchrotron radiation that is produced and the electrons in the beam induces a periodic bunching of the electrons, greatly increasing the intensity of radiation produced at a particular wavelength. Depending only on a phase match between the electron energy and the magnetic period, the wavelength of the FEL radiation can be continuously tuned within a wide spectral range. The FEL concept can be adapted to produce radiation wavelengths from millimetres to Angstroms, and can in principle produce hard x-ray beams with unprecedented peak brightness, exceeding that of the brightest synchrotron source by ten orders of magnitude or more. This paper focuses on short-wavelength FELs. It reviews the physics and characteristic properties of single-pass FELs, as well as current technical developments aiming for fully coherent x-ray radiation pulses with pulse durations in the 100 fs to 100 as range. First experimental results at wavelengths around 100 nm and examples of scientific applications planned on the new, emerging x-ray FEL facilities are presented.

A nondestructive radiation detector unit is under construction at the TESLA Test Facility at DESY providing monitoring of the radiation (pulse energy, transverse intensity distribution, and statistical properties). The concept of the detector design is based on experience obtained during operation of TTF FEL, Phase 1. Key element of the detector is a wide dynamic range micro-channel plate (MCP) which detects scattered radiation from a thin gold wire crossing photon beam. Operating wavelength range of the detector is from 6 to 100 nm . An important feature of the MCP-based detector is that it is capable to cover all dynamic range of the radiation intensity, from the level of spontaneous emission up to the saturation level of SASE FEL.

Yeast display of antibody fragments has proven to be an efficient and productive means for directed evolution of single-chain Fv (scFv) antibodies for increased affinity and thermal stability and, more recently, for the display and screening of a non-immune scFv and immune Fab libraries. A major strength of yeast display as a novel antibody discovery platform is the ability to characterize the binding properties, i.e., the affinity and epitope binding characteristics, of a clone without the need for subcloning, expression and purification of the scFv. This review focuses on novel attributes of yeast display for antibody engineering endeavors.

Gigawatt level radiation pulses at wavelengths between 80 and 120 nm and a pulse duration below 100 fs have recently been produced by a single-pass free electron laser at DESY. The radiation has been characterized with respect to pulse energy, statistical properties, spectral distribution and coherence. It has also been used for first experiments on solids and gases demonstrating the potential of the new source. The facility is currently upgraded to higher energy and is planned to start user operation in 2004. Based on this work a large free electron laser laboratory with several experimental stations for the hard X-ray regime down to 1 A will be built at DESY which could start user operation at the beginning of the next decade.

During the last few years free electron lasers (FELs) based on self-amplified spontaneous emission (SASE) have been demonstrated at wavelengths of 12 μm [1], 830 nm [2], 530 nm [3] and 385 nm [3], and around 100 nm [4]. Recently, saturation has been observed in the vacuum ultraviolet (VUV) spectral region between 82 nm and 125 nm at the TESLA Test Facility (TTF) at DESY. The radiation pulses have been characterized with respect to pulse energy, statistical fluctuations, angular divergence and spectral distribution, both in the linear gain and in the saturation regime of the FEL [5-6]. The results are in good agreement with theoretical simulations, providing a solid basis for other projects aiming at still shorter wavelengths down to the 0.1 nm range [7-8].

A nonimmune library of 10(9) human antibody scFv fragments has been cloned and expressed on the surface of yeast, and nanomolar-affinity scFvs routinely obtained by magnetic bead screening and flow-cytometric sorting. The yeast library can be amplified 10(10)-fold without measurable loss of clonal diversity, allowing its effectively indefinite expansion. The expression, stability, and antigen-binding properties of >50 isolated scFv clones were assessed directly on the yeast cell surface by immunofluorescent labeling and flow cytometry, obviating separate subcloning, expression, and purification steps and thereby expediting the isolation of novel affinity reagents. The ability to use multiplex library screening demonstrates the usefulness of this approach for high-throughput antibody isolation for proteomics applications.

A beamline designed to reduce the spectral bandwidth of the DESY XUV FEL is described. The beamline is intended to cover the wavelength range from 6.4 to 50 nm with three variable line spacing gratings. A plane mirror in front of the grating is used to maintain constant magnification in the dispersion direction. The electric field generated by the first undulator at three wavelengths, 6.4, 13, and 25 nm, is propagated through the beamline. The results show that the beamline has the resolution and imaging properties required for seeding the second undulator at these wavelengths.

First lasing of a single-pass free electron laser below 100 nm wavelength was recently observed at the TESLA Test Facility at DESY, after a singular experiment with very high gain at Los Alamos National Laboratory at 12 μm wavelength in 1997 and a very recent experiment at 530 nm at Argonne National Laboratory. These novel devices are based on the principle of self-amplified spontaneous emission (SASE), allowing very high gain up to saturation in a single pass through a long periodic magnetic structure. This concept does not require any optical components and promises to produce intense, sub-picosecond laser pulses for a very wide, continuous range of wavelengths down to approximately 0.1 nm. The experimental results at DESY and the other laboratories are in agreement with theory and indicate that SASE FELs will soon be available for experiments in the VUV and soft X-ray region. This paper gives an overview of the status of the present SASE projects and the anticipated research and development in the near future. It focuses particularly on the recent results at DESY and the current program towards a VUV user facility.

Crossover femorofemoral bypass graft (CFFBG) was proposed in the early days of modern vascular surgery to treat patients affected with unilateral iliac artery disease who were a high surgical risk. We investigated factors influencing short- and long-term outcomes of CFFBG:The study was designed as a retrospective clinical study in a university hospital setting with a base of 228 patients. Of these patients, 154 (67.5%) presented a high surgical risk. The indication for operation was limb-threatening ischemia in 188 (82.5%) patients. All patients underwent CFFBG: The procedure was performed in 150 patients as the primary operation and in 78 patients after previous vascular graft failure or infection, or both. A preoperative percutaneous transluminal angioplasty was performed in 57 patients (25%) to correct donor iliac artery disease. In 127 patients (55.7%), an associated vascular procedure was performed to improve the outflow. Postoperative complications; 5- and 10-year primary, secondary, and limb salvage rates; and factors influencing short- and long-term results were assessed.Thirteen (5.7%) postoperative deaths occurred. Postoperative mortality and morbidity rates were significantly higher in patients aged more than 65 years (7.9% versus 3.5% and 18.6% versus 6.1%, respectively, P.03). Primary and secondary patency rates at 5 and 10 years were 70.2% and 48.1%, 82.8% and 63.2%, respectively; 5- and 10-year limb salvage and survival rates were 85.5% and 80.1%, 63.3% and 31.0%, respectively. Ten-year primary and secondary patency and limb salvage rates were significantly lower when the procedure was performed after previous vascular graft failures (50.2% versus 26.5%, P.007; 74.1% versus 44.1%, P.01; and 84.3% versus 72.5%, P.03, respectively). Five- and 8-year patency rates of autogenous vein CFFBG (34.3% and 22.8%, respectively, P.03) were significantly lower than those of expanded polytetrafluoroethylene (71.1% and 59.8%, respectively) and polyester (77.3% and 50.3%, respectively) CFFBG: Moreover, 5- and 10-year primary and secondary patency rates were significantly better when externally supported grafts were used as compared with those without external support (80.1% and 69.9% versus 61.1% and 21.1%, P.01; 88.8% and 75.9% versus 78.9% and 45.4%, P.05, respectively). Multivariate analysis showed that the only variable associated with poor primary and secondary patency and limb salvage rates was the operation performed after previous vascular graft failures (P.04, P.03 and P.05, respectively).CFFBG allows early and long-term results similar to those obtained with reconstructions originating from the aorta when it is performed as a primary operation when an adequate outflow is provided and externally supported prosthetic material is used.

Background: Dislocation injuries of the glenohumeral joint are common in the general public and generally are corrected without complication. One serious complication with shoulder dislocations, or the subsequent reduction, is a lesion to the axillary artery. This specific complication is most frequently seen in the elderly population, where vascular structures have become less flexible. Also, these injuries are most common in association with anterior dislocations of the shoulder. Objectives: To bring awareness to the possibility of axillary artery injury with inferior dislocation of the shoulder, the treatment options, and a review. Case Report: We report a 15-year-old male athlete who inferiorly dislocated his shoulder during wrestling practice. The injury was reduced at the scene with manual traction and the patient was transferred to our clinic for evaluation. The patient was determined to have a pseudoaneurysm of the axillary artery, and the history and treatment of the illness are presented. Conclusion: Axillary artery injuries secondary to shoulder dislocations are rare, especially in the young athlete, and proper recognition and treatment offer patients a full recovery.

The local structure of the CuO2 planes in Nd2−xCexCuO4−δ (x=0, 0.15; δ∼0.01) has been examined by temperature-dependent Cu K-edge extended X-ray absorption fine structure (EXAFS) spectroscopy. Three different Cu–O distances can be extracted up to at least 100 K, indicating that the atomic structure of the CuO2 planes deviates from the T′ structure much more than it was expected. Positions of the displaced O1 atoms for x=0.15 were obtained from comparative analysis of the experimental and calculated polarized Cu K-edge X-ray absorption near-edge structure, taking into account many-body excitations in the CuO2 planes.

ICAM-3 is a preferred counterreceptor for the leukocyte αLβ2 integrin. It activates T cells through outside-in signaling, but polymorphonuclear leukocytes (PMN) are reported to be refractory to ICAM-3 stimulation. We found that engagement of ICAM-3 by a mAb (CAL3.10), which binds in the region where αLβ2 integrin binds, activates PMN homotypic aggregation and adhesion to surfaces. These functional changes were due to ICAM-3 outside-in signaling because aggregation and adhesion were β2 integrin-dependent, tyrosine kinase and protein kinase C activities were activated, and there was a reorganization of the cytoskeleton. This reorganization and kinase activity was required for ICAM-3-, but not FMLP-, induced aggregation. This is not an Fc-mediated event as an appropriate anti-ICAM-3 F(ab′)2 fragment still induced aggregation. Another anti-ICAM-3 Ab (HP2/19), which activates T cells, did not activate PMN. Strikingly, anti-ICAM-3 did not induce degranulation or cause an increase in surface β2 integrin expression, so adhesion and aggregation were due solely to the activation of the constitutively expressed β2 integrins. Aggregation in response to ICAM-3, but not FMLP, was compromised at lower cell densities, showing that β2 integrin recruitment enhances aggregation under suboptimal conditions. We conclude that engagement of ICAM-3 stimulates PMN as well as T cells, but that the appropriate epitope varies between these two cells. ICAM-3 outside-in signaling reorganizes the cytoskeleton without causing degranulation, induces serine and tyrosine kinase activation, and activates existing surface β2 integrins to a proadhesive state.

The creation of a core hole in a molecule leads to vibrationally and electronically excited states of the resulting ion as the system adjusts to the new molecular potential. These can be observed in the corresponding photoelectron spectrum as vibrational fine structure on the main line and as satellite excitations, respectively. In the region near the photoelectron threshold, however, other phenomena occur, such as shape resonances, multi-electron excitations and conjugate satellite processes, which affect the partial cross-sections of the various channels. As an example, we present C 1s photoelectron spectra of ethene (C 2 H 4 ) measured with high energy resolution in the near-threshold region. The vibrational fine structure on the C 1s −1 line can be fitted with two progressions with energies of 185(±5) meV and 424(±10) meV, which can be assigned to totally symmetric modes. It is expected that vibronic coupling occurs, as in the case of the corresponding photoabsorption spectrum, and that an antisymmetric stretching mode contributes to the higher energy progression. This cannot be determined from the fit, however. There is no definitive evidence for a shape resonance in the C 1s single-hole cross-section. In addition, the C 1s shake-up satellite spectrum was also measured with high resolution in the near-threshold region. Apart from the well-resolved π–π* satellites, S 0 and S 1 , the measurements revealed several other peaks. Their partial cross-sections and asymmetry parameters indicate the existence of conjugate processes.

(1998). The Vacuum Ultraviolet Free-Electron-Laser at DESY. Synchrotron Radiation News: Vol. 11, No. 1, pp. 14-21.

The C 1 s −π ∗ band in the high-resolution photoabsorption spectra of the ethyne isotopomers C2H2, C2D2 and C2HD is found to be dominated by vibronic coupling effects. There is quantitative agreement between experiment and a recent theoretical model which treats vibronic coupling in both the core and valence orbital spaces. The theoretical analysis shows that a strong excitation of the bending modes dominates the observed spectra.

The C 1s partial photoionization cross section and asymmetry parameter ? of the C2H2 molecule have been determined with high-energy resolution between threshold and 360 eV. The C 1s shake-up satellite spectrum is richly structured; the cross section of several satellites increases strongly near threshold, which indicates that there is a conjugate contribution to their intensity. It is shown that the large enhancement in the total photoabsorption cross section between 305 and 320 eV, previously attributed to a ?* shape resonance, is largely due to this photon energy dependence of the shake-up transitions.

Background. The aim of this study was to investigate surgical indications and the long-term outcomes of aortoliofemoral reconstructions in adults younger than 45 years. Methods. Between 1973 and 1990, 1256 patients underwent infrarenal abdominal aortic reconstruction for aortoiliofemoral occlusive disease. Sixty-eight (5.4%) patients (group 1) were less than 45 years old and form the basis of the analysis. They were retrospectively compared with two additional groups of patients 45 years and older selected from the entire series. Patients in group 2 (n = 100) were randomly chosen to determine differences in risk factors, associated diseases, operative indications, preoperative findings, and outcomes. Patients in group 3 (n = 70) were matched with those in group 1 for gender, risk factors, associated diseases, preoperative findings, and operative indications to assess the importance of age in determining the short- and long-term outcomes of aortoiliofemoral reconstructions. Results. Postoperative mortality rates (1.5%, 4%, and 4.3% for groups 1, 2, and 3, respectively) and major complication rates (4.4%, 7%, and 7.1% for groups 1, 2, and 3, respectively) were comparable among the three groups. Ten-year secondary patency rates were 84.6%, 70.6%, and 80.3%, for groups 1, 2, and 3, respectively (p = not significant). Ten-year limb salvage rates were 86.9%, 78.2%, and 80.6%, for groups 1, 2, and 3, respectively (p = not significant). During follow-up a significantly higher percentage of myocardial infarction was recorded in group 1 as compared with group 2 (p < 0.03) and group 3 (p < 0.04). The 10-year survival rate for group 1 was significantly lower than that of group 2 (29.0% versus 46.9%; p < 0.005). Conclusions. Aortoliofemoral reconstruction in patients younger than 45 years is a safe procedure with low operative risks and good long-term results in patency and limb salvage rates. However, life expectancy is poor because of the high incidence of deaths related to coronary artery disease.

Purpose: The aim of the study was to investigate surgical indication and long-term outcome of carotid endarterectomy (CE) in young adults.Methods: Between 1973 and 1990, 1693 patients underwent CE. Forty-nine patients (group 1) 35 to 45 years of age who had carotid artery stenosis greater than 70%, formed the basis for the analysis. They were compared with two additional groups of patients older than 45 years of age selected from the entire series. Group 2 was randomly chosen to determine differences in risk factors, associated diseases, operative indications, preoperative findings, and outcome. Group 3 was matched with patients in group 1 for sex, risk factors, associated diseases, preoperative findings, and operative indications to assess the importance of age in determining the short- and long-term outcome of CE.Results: Postoperative mortality, cerebrovascular accidents, and cardiac complications in patients of group 1 (2%, 2%, and 2%, respectively) were similar to those of the other groups ( p = NS). During the follow-up (76.7 ± 3.6 months; range, 1 to 120 months) the incidence of strokes and transient ischemic attacks in group 1 was lower than in group 2 ( p < 0.05) but similar to group 3 ( p = NS). Ten-year disease-free intervals were 75.7%, 58.7%, and 77.6%, respectively, for groups 1, 2, and 3. Mortality rate unrelated to cerebrovascular disease was similar between group 1 and group 3 ( p = NS) but was higher in group 1 than in group 2 ( p < 0.02). Ten-year survival rates were 46.1%, 71.7%, and 55.5%, respectively, for group 1, 2, and 3.Conclusions: CE in patients younger than 45 years of age is a safe procedure with low operative risks and good disease-free intervals. However, life expectancy is poor because of the high incidence of deaths resulting from complications of atherosclerosis.(J Vasc Surg 1997;25:464-70.)

The angle-resolved N 1s photoelectron spectrum of N2 has been measured with high resolution in the threshold region. An analysis of the vibrational fine structure yields a vibrational energy of 314(4) meV and a lifetime broadening of 103(10) meV for the core-ionized molecule. As in the case of C 1s ionization of CO, the vibrational fine structure changes considerably with photon energy in the region of both the sigma* shape resonance and the double excitations. Both the vibrationally resolved partial photoionization cross sections and asymmetry parameters have been determined in this photon energy range. The calculated cross sections in the literature are in reasonable agreement with experiment. In addition, we have measured the cross sections and asymmetry parameters of the most intense direct and conjugate shake-up satellites. The behaviour of the pi-pi* satellites is found to differ significantly from that of the corresponding C 1s satellites of CO.

Recurrence or persistence of neurologic symptoms after surgical treatment of patients with thoracic outlet syndrome (TOS) are reported to be as high as 25%. To identify factors affecting the long-term outcome of surgical treatment of patients with TOS, we reviewed our 20-year experience.One hundred thirty-four transaxillary first rib resections were performed on 118 patients (43 men, 75 women, mean age 38 +/- 13 years). Eighty-three operations (61.9%) were undertaken to relieve symptoms resulting from compression of the lower roots of the brachial plexus, 37 (27.6%) for compression of both lower and upper roots, and 14 (10.5%) for lower root and vascular symptoms. All patients underwent a transaxillary extraperiosteal first rib resection with transection of the scalene muscles. In 73 cases (54.5%) a resection of the anterior scalene muscle was also performed. A cervical rib was removed in 28 cases (20.1%), and anomalous fibrous bands adjacent to the neurovascular bundle were resected in 41 cases (30.6%).No major complications were observed. Of 105 patients (118 procedures) followed up (mean follow-up, 99 +/- 72 months), good to excellent results were obtained in 96 cases (81.4%) and fair to poor results were recorded in 22 cases (18.6%). The presence of a long posterior first rib stump, measured from the chest x ray films, was the strongest determinant of the long-term results among the variables examined (p0.0001). Reoperation, consisting of neurolysis and resection of the stump, was performed in 16 patients. The results were excellent in all cases at a mean follow-up of 66 +/- 46 months. Primary and secondary 10-year, actuarial freedom rates from recurrent symptoms were 80.9% and 93.1%, respectively.Our results suggest that the long-term outcome after surgery for TOS was strongly influenced by the extent of the first rib resection.

We have measured the C 1s near-edge photoabsorption spectrum of the ethene isotopomers C 2 H 4 , C 2 D 4 , (1, 1)C 2 H 2 D 2 and cis-C 2 H 2 D 2 at high resolution using order-sorted, monochromatised undulator radiation. An analysis of the vibrational fine structure on the 1s-π ∗ band indicates strong excitation of non-totally symmetric modes and provides direct evidence for symmetry breaking and core hole localisation.

The partial photoionization cross sections and angular distributions of the C 1${\mathit{s}}^{\mathrm{\ensuremath{-}}1}$ and O 1${\mathit{s}}^{\mathrm{\ensuremath{-}}1}$ single-hole states of ${\mathrm{CO}}_{2}$ have been measured with high precision near threshold. The 4${\mathrm{\ensuremath{\sigma}}}_{\mathit{u}}^{\mathrm{*}}$ shape resonance is well reproduced in the 1s single-hole cross sections, but strong site-specific effects are observed with respect to both its energy and intensity. A striking feature of the present data is the presence of fine structure in the 1s single-hole cross sections ${\mathrm{\ensuremath{\sigma}}}_{\mathrm{SH}}$ due to multielectron excitations: virtually all spectral details in the total 1s cross sections ${\mathrm{\ensuremath{\sigma}}}_{1\mathit{s}}$ are also present in ${\mathrm{\ensuremath{\sigma}}}_{\mathrm{SH}}$ implying that multielectron excitations couple strongly to the underlying 1s continuum. The decay dynamics of the double-excitation feature at 303.5 eV in the C 1s cross section of ${\mathrm{CO}}_{2}$ have been characterized by Auger spectroscopy. Partial cross sections and angular distributions have also been measured for the first group of strong shake-up satellites in the C 1s photoelectron spectrum. Similar to the C 1s ionization of CO, a strong enhancement of intensity near threshold is observed for some satellite channels as well as the occurrence of features that are not present in the sudden limit. The latter are attributed to conjugate shake-up.

A substantial enhancement of intensity in the high-energy part of the ${\mathrm{N}}_{2}$ KLL Auger spectrum has been observed at photon energies a few tens of eV above the N 1s threshold. By monitoring the corresponding 1s photoelectron spectrum, we show that the effect is due to the emergence of strong conjugate shake-up satellites. As shown in previous e-2e studies for CO, such Auger spectra are useful in determining the intensity behavior of shake-up satellites in the immediate threshold regions.

The C 1s and N 1s main lines in the photoelectron spectra of CO, CO2, CH4, C2H2, C2H4, C2H6, N2, and N2O have been measured with high resolution in the threshold region, revealing in each case the extent of the rich vibrational fine structure. Using a simple line shape analysis which allows for the effect of post-collision interaction, the vibrational energies and approximate lifetimes of the core-excited ions are determined. The relative intensities of the vibrational lines change dramatically with photon energy due to the influence of shape resonances and double excitations.

The results of a spin-polarized photoemission study of the Fe 3s level clearly reveal the multiplet structure characterizing the final states of the excitation process. The energy separation between the high-spin and low-spin ionic states of 3.5 eV is smaller than has previously been measured, to our knowledge. The two spin components of the high-spin ionic state are clearly resolved and shown to be separated in binding energy by 0.9 eV. Line-shape fitting provides evidence that the individual peak widths reflect the total spin of the ionic final state rather than the spin of the core hole.

An Yb:YAG thin-disk laser amplifier is presented capable of amplifying pulses to a maximum average power of 4.45 kW at burst repetition rates of 100 kHz as pump amplifier for an optical parametric amplifier system.

A case of intrapericardial giant lymph node hyperplasia (localized hyaline-vascular variant of Castleman's disease) is reported. The large tumor was successfully removed, and at a twelve-year follow-up there are no signs of recurrence. This is the first case reported in the literature of an intrapericardial Castleman's disease localization. Embryologic, surgical, and prognostic implications of this finding are briefly discussed.

Early results of laser-assisted balloon angioplasty (LABA) and peripheral directional atherectomy (PDA) are encouraging. The true value of these procedures has remained in doubt, however, because of the absence of data on long-term objective patency rates.From August 1988 through October 1993, LABA and PDA were performed on 151 limbs of 124 patients. Presenting symptoms were mild-to-severe claudication in 128 limbs (63 LABA, 65 PDA) and rest pain or necrosis in 23 (7 LABA, 16 PDA). Seventy-seven percent of the atherosclerotic lesions were localized in the iliofemoral tract (77% LABA, 76% PDA). Seventy limbs were treated with LABA and 81 with PDA.Initial hemodynamic and arteriographic success was achieved in 46 LABA limbs (66%) and 75 PDA limbs (93%) (P0.002). Mean follow-up was 16 +/- 2 months after LABA and 18 +/- 1 months after PDA. During this time, 32 failures were recorded in limbs treated with LABA, and 29 in limbs treated with PDA. The patency rate at 40 months was 23% in the LABA group and 45% in the PDA group (P0.005). Patency rates were not affected by the length or site of the arterial lesion or the runoff score.PDA had a better long-term patency rate than LABA, but long-term results were dismal with both techniques. PDA appears to have a limited role and LABA no role in the treatment of lower extremity occlusive disease.

FLASH has been a user facility since 2005, delivering radiation in the wavelength range between 7 and 47 nm using the SASE principle. After the present upgrade, the wavelength range is extended to 4.45 nm. With the third harmonic accelerating module in place to linearize the longitudinal phase space, the stability and reproducibility of the machine is substantially improved. The user requests for beam time by far exceeds the time available. In order to increase user beam time and to improve the radiation properties delivered to users, a major extension of the user facility called FLASH II has been proposed by DESY in collaboration with the HZB. FLASH II is a seeded FEL in the parameter range of FLASH. As logical continuation, the seeding with HHG which started with sFLASH will result in direct seeding. Because in the foreseeable future there will probably not be HHG seed lasers available at high repetition rates down to wavelengths of 4 nm, a cascaded HGHG scheme is proposed to produce short wavelengths. After a first design report, the project now enters its technical design phase. During this time, the FLASH beam parameters after the present upgrade 2009/2010 will be characterized and the present design will be re-evaluated and adjusted. In addition, start-to-end simulations will complete the simulations which have been performed so far, including a design of the extraction area.

Lifetime vibrational interference effects modulate the line shapes observed in high-resolution studies of the decay of ultra-short-lived core—hole excited states in molecules. We have analyzed the decay of the 1σ−1u 1π3g core excited state in O2, where for the first time subsets of vibronic eigenfunctions could be selected. We demonstrate that this type of spectroscopy can be used to verify the predictions of quantum mechanical interference theory describing the time evolution of coherently excited vibrational states on the femtosecond time scale.

From April, 1990, to April, 1992, peripheral atherectomy using a Simpson AtheroCath was performed in 46 patients (56 limbs) with a total of 106 lesions. There were 100 stenoses (74 eccentric, 26 concentric) and 6 occlusions. Success was achieved in 103/106 (97%) procedures (97 stenoses and 6 occlusions), reducing the lesion to < 35% (stenoses: 81±13% to 22±9%, p < 0.0001, and the occlusions : 100% to 16±8%; p < 0.0001). Ankle/brachial index (ABI) improved from 0.58±0.17 to 0.85 ± 0.22 (p < 0.0001). Clinical success was achieved in 42 patients (91%). Complications occurred in 6 patients (13%): groin hematoma in 5, and in 1, acute occlusion of the femoral artery with distal embolization. There were 13 hemodynamic failures in 11 patients (28%) with an ABI reduction of more than 0.15 with respect to the maximum early postoperative level, over a mean follow-up of 15.1 months. Failure of the procedure was confirmed by arteriography in only 4 cases. Cumulative eighteen-month patency rates were 60% using arteriographic assessment and 44% for hemodynamic assessment (p < 0.025). Patency rates were 56% for the patients with a runoff score ranging between 1 and 5 and 17% with a score > 5 (p < 0.0025). A reduction of ABI during follow-up is not a true indicator of procedural failure, but it correlates with possible progression of distal disease. Evaluation of preoperative runoff may be used as a prognostic indicator.

We have measured partial photoionization cross sections σ and asymmetry parameters β of the C 1s main line and the π→π* shake‐up satellites of the isoelectronic molecules formaldehyde and ethylene in the near threshold region. In all channels we observe a strong cross section enhancement and a decrease in the β parameter due to a shape resonance in the continuum. For each molecule the variation of σ and β with photoelectron kinetic energy is nearly identical for main line and satellites indicating only relatively small modifications of the effective molecular potential induced by the additional π→π* excitation. There are no indications of conjugate shake‐up processes in either molecule.

FLASH (free electron laser in Hamburg) is a unique, ultra-brilliant soft x-ray source providing highly coherent femtosecond pulses, currently in a wavelength range of 6.8–47 nm. Up to several 1012 coherent photons within a 10–70 fs pulse allow the study of dynamical changes in nanometer-sized structures. This is a big step towards the ultimate goal of observing femtosecond dynamics on the atomic length scale, for example 'watching bio-machines at work'. In this review, the properties of FLASH are summarized with a focus on coherence, and the potential of FLASH for structural investigations is illustrated with an overview of the recently performed coherent imaging experiments.