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The ECHo experiment aims at determining the effective electron neutrino mass by analyzing the endpoint of the 163Ho electron capture spectrum. High energy resolution detectors with a well-tailored detector response are the essential ingredient for the success of the ECHo experiment. Metallic magnetic calorimeter arrays enclosing 163Ho have been chosen for the ECHo experiment. The first MMC array, ECHo-1k, showed excellent performances with an average energy resolution of 5.5 eV FWHM @ 5.9 keV. Based on the results obtained with the ECHo-1k array, optimization studies have paved the way towards a new detector design for the next experimental phase, ECHo-100k. The ECHo-100k chip features an optimized single pixel design to improve the detector performance as well as an upgraded on-chip thermalization layout. The newly fabricated ECHo-100k detectors have been fully characterized at room temperature, at 4 K and at millikelvin temperature. The obtained results show that the ECHo-100k array achieved the expected performance with an average energy resolution of 3.5 eV FWHM @ 5.9 keV, fulfilling the requirements for the ECHo-100k experimental phase. [ABSTRACT FROM AUTHOR]

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Present-day laser-spectroscopy experiments increasingly rely on modern commercial devices to monitor, stabilize, and scan the wavelength of their probe laser. Recently, new techniques are capable of achieving unprecedented levels of precision on atomic and nuclear observables, pushing these devices to their performance limits. Considering the fact that these observables themselves are deduced from the frequency difference between specific atomic resonances, in the order of MHz–GHz, the uncertainty on the output of the device measuring the wavelength is often directly related to the final systematic uncertainty on the experimental results. Owing to its importance, the performance of several commercial wavelength meters was compared against different reference sources, including a Scanning Fabry–Pérot Interferometer (SFPI) and a frequency comb. Reproducible, wavelength- and device-dependent disagreements are observed, potentially skewing the experimental output at high precision. In this paper, a practical and relatively inexpensive wavelength meter characterization procedure is presented and validated. This method is capable of improving the precision on wavelength differences considerably depending on the device, while together with a second investigation that is published separately, (König et al., in Appl Phys B, 2020), it offers a full description of the expected wavelength meter performance for users. [ABSTRACT FROM AUTHOR]

Background: Pelvic ring injuries are serious injuries, often associated with substantial morbidity and mortality rates. The long-term consequences of these injuries might affect the patients' personal life. Our aim was to assess the long-term effects of pelvic ring injuries on physical functioning and quality of life (QoL) using validated patient-reported outcome measures (PROMs) and comparing these results to normative data from the general population.Patients and Methods: A retrospective cohort study was conducted on adults treated for pelvic ring injuries between 2007 and 2016. Demographics, fracture type, injury mechanism, treatment and complications were recorded. PROMs questionnaires concerning physical functioning (SMFA) and quality of life (EQ-5D) were used. Patients were divided according to their age (18-30, 31-64, 65 and older) and fracture type (Tile/AO type A, B or C). Differences in SMFA and EQ-5D scores of the operatively and non-operatively treated patients and between the study population and general population were analyzed.Results: A total of 413 patients were identified of which 279 were eligible for follow-up. One-hundred and ninety-two (69%) patients responded with a mean follow-up of 4.4 years. Patients reported a median score of 13.9 on the SMFA function index, 16.7 on the bother index, 12.5 on the lower extremity, 18.8 on the activities of daily living and 23.4 on the emotion subscale. A median EQ-5D score of 0.8 was reported. There was no difference in physical functioning and QoL between operatively and non-operatively treated patients. Comparison of these results to normative data of the general population revealed a significant (P < 0.05) decrease in physical functioning and QoL in patients with all types of pelvic ring injuries.Conclusion: Long-term physical functioning and QoL in patients who had sustained a pelvic ring injury seems fair, although significantly decreased in comparison with their peers from the general population. [ABSTRACT FROM AUTHOR]

A neutral particle detector is presented, in which the traditionally used target material, indium tin oxide (ITO), is replaced by graphene. The graphene-based detector enables collinear photodetachment measurements at a significantly shorter wavelength of light down to 230 nm compared to ITO-based detectors, which are limited at 335 nm. Moreover, the background signal from the photoelectric effect is drastically reduced when using graphene. The graphene based detector, reaching 1.7 eV further into the UV energy range, allows increased possibilities for photodetachment studies of negatively charged atoms, molecules, and clusters. [ABSTRACT FROM AUTHOR]

Purpose: Surgery for hip fractures is frequently followed by complications that hinder the rehabilitation of patients. The aim of this study was to describe the incidence rate and type of complications, including mortality, after hip fracture surgery, and to identify the risk factors of these complications that may be amenable to prevention.Methods: Prospective cohort study of all consecutive patients aged ≥60 treated for a hip fracture at University Medical Center Groningen between July 2009 and June 2013. All patients were treated in a comprehensive multidisciplinary care pathway. Logistic regression analyses were used to investigate which variables were significant risk factors for the occurrence of complications. Additional analyses were conducted to investigate whether the independent variables were significant risk factors for several specific complications and mortality.Results: The study population consisted of 479 patients with a mean age of 78.4 (SD 9.5) years; 33% were men. The overall complication rate was 75%. Delirium was the complication seen most frequently (19%); the incidence of surgical complications was 9%. Most risk factors for complications were not preventable (high comorbidity rate, high age and dependent living situation). However, general anesthesia (OR 1.51; 95% CI 0.97-2.35) and delay in surgery (OR 3.16; 95% CI 1.43-6.97) may be risk factors that can potentially be prevented. Overall, the mortality risk was not higher in patients with a complication, but delirium and pneumonia were risk factors for mortality.Conclusion: The overall complication rate after hip fracture surgery was high. Only few complications were potentially preventable. [ABSTRACT FROM AUTHOR]

Copyright of Anaesthesist is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Posttraumatic osteomyelitis (PTO) is a feared complication after surgical fracture care. Late diagnosis can result in interrupted and prolonged rehabilitation programmes, inability to work, medical dependency, unnecessary hospital admissions, and high medical and non-medical costs. Primary aim of this study was to assess preferred diagnostic imaging strategies for diagnosing PTO amongst orthopaedic and trauma surgeons, radiologists, and nuclear medicine physicians. Secondary aims were to determine the preferred serum inflammatory marker for diagnosing PTO and the existence of a local hospital protocol to diagnose and manage PTO.Materials and methods: This study utilised an online survey based on four clinical scenarios, varying from early to late onset of PTO. It was designed to assess individual practitioners’ current preferred diagnostic strategy for diagnosing PTO. Eligible study participants were medical specialists and registrars in orthopaedic and trauma surgery, musculoskeletal (MSK) radiology, and nuclear medicine.Results: There were 346 responders: 155 trauma surgeons, 102 orthopaedic surgeons, 57 nuclear medicine physicians, and 33 MSK radiologists. Trauma surgeons favour FDG-PET to image PTO, while orthopaedic surgeons prefer WBC scintigraphy. A similar difference was seen between radiologists and nuclear medicine physicians (MRI versus nuclear medicine imaging). CRP was regarded as the most useful serum inflammatory marker. Only one-third of all responders was aware of a local hospital protocol for the treatment of osteomyelitis.Conclusions: The availability of and awareness towards local protocols to diagnose and treat PTO is poor. The results of this study support the need for future randomised controlled trials on optimal diagnostic strategies for PTO. [ABSTRACT FROM AUTHOR]

Background: The treatment of unstable displaced proximal humeral fractures, especially in the elderly, remains controversial. The objective of the present prospective, multicenter, observational study was to evaluate the functional outcome and the complication rate after open reduction and internal fixation of proximal humeral fractures with use of a locking proximal humeral plate.Methods: One hundred and eighty-seven patients (mean age, 62.9 +/- 15.7 years) with an acute proximal humeral fracture were managed with open reduction and internal fixation with a locking proximal humeral plate. At the three-month, six month,and one-year follow-up examinations, 165 (88%), 158 (84%), and 155 (83%) of the 187 patients were assessed with regard to pain, shoulder mobility, and strength. The Constant score was determined at each interval, and the Disabilities of the Arm, Shoulder and Hand (DASH) score was determined for the injured and contralateral extremities at the time of the one-year follow-up.Results: Between three months and one year, the mean range of motion and the mean Constant score for the injured shoulders improved substantially. Twelve months after surgery, the mean Constant score for the injured side was 70.6 +/- 13.7 points, corresponding to 85.1% +/- 14.0% of the score for the contralateral side. The mean DASH score at the time of the one-year follow-up was 15.2 +/- 16.8 points. Sixty-two complications were encountered in fifty-two (34%) of 155 patients at the time of the one-year follow-up. Twenty-five complications (40%) were related to incorrect surgical technique and were present at the end of the operative procedure. The most common complication, noted in twenty-one (14%) of 155 patients, was intraoperative screw perforation of the humeral head. Twenty-nine patients (19%) had an unplanned second operation within twelve months after the fracture.Conclusions: Surgical treatment of displaced proximal humeral fractures with use of the locking proximal humeral plate that was evaluated in the present study can lead to a good functional outcome provided that the correct surgical technique is used. Because many of the complications were related to incorrect surgical technique, it behooves the treating surgeon to perform the operation correctly to avoid iatrogenic errors. [ABSTRACT FROM AUTHOR]

Background: The treatment of unstable displaced proximal humeral fractures, especially in the elderly, remains controversial. The objective of the present prospective, multicenter, observational study was to evaluate the functional outcome and the complication rate after open reduction and internal fixation of proximal humeral fractures with use of a locking proximal humeral plate.Methods: One hundred and eighty-seven patients (mean age, 62.9 +/- 15.7 years) with an acute proximal humeral fracture were managed with open reduction and internal fixation with a locking proximal humeral plate. At the three-month, six-month, and one-year follow-up examinations, 165 (88%), 158 (84%), and 155 (83%) of the 187 patients were assessed with regard to pain, shoulder mobility, and strength. The Constant score was determined at each interval, and the Disabilities of the Arm, Shoulder and Hand (DASH) score was determined for the injured and contralateral extremities at the time of the one-year follow-up.Results: Between three months and one year, the mean range of motion and the mean Constant score for the injured shoulders improved substantially. Twelve months after surgery, the mean Constant score for the injured side was 70.6 +/- 13.7 points, corresponding to 85.1% +/- 14.0% of the score for the contralateral side. The mean DASH score at the time of the one-year follow-up was 15.2 +/- 16.8 points. Sixty-two complications were encountered in fifty-two (34%) of 155 patients at the time of the one-year follow-up. Twenty-five complications (40%) were related to incorrect surgical technique and were present at the end of the operative procedure. The most common complication, noted in twenty-one (14%) of 155 patients, was intraoperative screw perforation of the humeral head. Twenty-nine patients (19%) had an unplanned second operation within twelve months after the fracture.Conclusions: Surgical treatment of displaced proximal humeral fractures with use of the locking proximal humeral plate that was evaluated in the present study can lead to a good functional outcome provided that the correct surgical technique is used. Because many of the complications were related to incorrect surgical technique, it behooves the treating surgeon to perform the operation correctly to avoid iatrogenic errors. [ABSTRACT FROM AUTHOR]

This paper presents the results of ionization scheme development for application at the ISOLDE Resonance Ionization Laser Ion Source (RILIS). Two new ionization schemes for mercury are presented: a three-step three-resonance ionization scheme, ionizing via an excitation to a Rydberg level and a three-step two-resonance ionization scheme, with a non-resonant final step to the ionization continuum that corresponded to a factor of four higher ionization efficiency. The efficiency of the optimal mercury ionization scheme was measured, together with the efficiency of a new three-step three resonance ionization scheme for tellurium. The efficiencies of the mercury and tellurium ionization schemes were determined to be 6 % and >18 % respectively. [ABSTRACT FROM AUTHOR]

Odd-parity autoionizing states of europium have been investigated by resonance ionization spectroscopy via two-step, two-resonance excitations. The aim of this work was to establish ionization schemes specifically suited for europium ion beam production using the ISOLDE Resonance Ionization Laser Ion Source (RILIS). 13 new RILIS-compatible ionization schemes are proposed. The scheme development was the first application of the Photo Ionization Spectroscopy Apparatus (PISA) which has recently been integrated into the RILIS setup. [ABSTRACT FROM AUTHOR]

The MEDICIS-PROMED Innovative Training Network under the Horizon 2020 EU program aims to establish a network of early stage researchers, involving scientific exchange and active cooperation between leading European research institutions, universities, hospitals, and industry. Primary scientific goal is the purpose of providing and testing novel radioisotopes for nuclear medical imaging and radionuclide therapy. Within a closely linked project at CERN, a dedicated electromagnetic mass separator system is presently under installation for production of innovative radiopharmaceutical isotopes at the new CERN-MEDICIS laboratory, directly adjacent to the existing CERN-ISOLDE radioactive ion beam facility. It is planned to implement a resonance ionization laser ion source (RILIS) to ensure high efficiency and unrivaled purity in the production of radioactive ions. To provide a highly efficient ionization process, identification and characterization of a specific multi-step laser ionization scheme for each individual element with isotopes of interest is required. The element lutetium is of primary relevance, and therefore was considered as first candidate. Three two-step excitation schemes for lutetium atoms are presented in this work, and spectroscopic results are compared with data of other authors. [ABSTRACT FROM AUTHOR]

We report on resonance ionization spectroscopy (RIS) of high-lying energy levels in dysprosium. We developed efficient excitation schemes and re-determined the first ionization potential (IP) via analysis of Rydberg convergences. For this purpose both two- and three-step excitation ladders were investigated. An overall ionization efficiency of 25(4) % could be demonstrated in the RISIKO mass separator of Mainz University, using a three-step resonance ionization scheme. Moreover, an extensive analysis of the even-parity 6s ns- and 6s nd-Rydberg-series convergences, measured via two-step excitation was performed. To account for strong perturbations in the observed s-series, the approach of multichannel quantum defect theory (MQDT) was applied. Considering all individual series limits we extracted an IP-value of 47901.76(5) cm, which agrees with the current literature value of 47901.7(6) cm, but is one order of magnitude more precise. [ABSTRACT FROM AUTHOR]

Operation of the novel laser ion source unit LIST (Laser Ion Source and Trap), operating at the on-line radioactive ion beam facility ISOLDE at CERN allowed for the production of ultra-pure beams of exotic isotopes far-off stability as well as direct isobar-free laser spectroscopy, giving access to the study of atomic and nuclear properties of so far inaccessible nuclides. We present a specific upgrade and adaption of the LIST targeted for high resolution spectroscopy with a Doppler-reduced perpendicular atom - laser beam geometry. With this PI-LIST (Perpendicularly Illuminated Laser Ion Source and Trap) setup, experimental linewidths below 100 MHz could be demonstrated in optical laser spectroscopy off-line, applying a pulsed injection-locked high repetition rate Ti:sapphire laser. A dual repeller configuration ensured highest suppression of isobaric interferences and almost background-free measurements on small samples in the order of 10 atoms. [ABSTRACT FROM AUTHOR]

In this article, the author reflects on recommendations for hip fractures suffered by elderly people. It mentions formation of the European Society for Trauma and Emergency Surgery (ESTES) Study Group to develop ESTES recommendations on proximal hip fractures. It also highlights importance of pain management and discusses several options apart from analgesic drugs such as traction splint and urinal catheter.

Breast cancer 1 (BRCA1)-associated breast cancers are mostly basal-like high-grade ductal carcinomas that frequently overexpress epidermal growth factor receptor (EGFR). Aberrant EGFR expression is correlated with disease progression, resistance to radiation and chemotherapy, and poor clinical prognosis. Although BRCA1 is involved in multiple cellular processes, its functional role in EGFR regulation remains enigmatic. Here, we report a previously unrecognized posttranscriptional mechanism by which BRCA1 regulates EGFR expression through the induction of miR-146a. We demonstrate that EGFR expression correlates negatively with BRCA1, whereas miR-146a levels increase with BRCA1. We show that BRCA1 binds to MIR146A promoter and activates transcription, which in turn attenuates EGFR expression. Knockdown of miR-146a in BRCA1-overexpressing cells negated this effect and suppressed its ability to inhibit proliferation and transformation. In archived triple-negative breast cancer samples, we show a strong positive correlation between BRCA1 and miR-146a expression. We also show that low expression of miR-146a strongly predicts positive lymph node status and is associated with distinctively poor overall survival of patients. Together, these observations provide an insight into a novel BRCA1miR-146aEGFR paradigm by which BRCA1 carries out an aspect of tumor suppressor function that is potentially amenable to therapeutic intervention. [ABSTRACT FROM AUTHOR]

Background: The Short Musculoskeletal Function Assessment (SMFA) is widely used in both research and clinical practice. Despite its frequent use, normative data of the SMFA have remained limited. Aim of this study was to gather normative data for the Dutch SMFA (SMFA-NL). Methods: The SMFA-NL consists of two indices ( function index and bother index) and four subscales ( upper extremity dysfunction, lower extremity dysfunction, mental and emotional problems, and problems with daily activities). A total of 900 patients were invited to fill in the SMFA-NL. Six age groups (18-24, 25-34, 35-44, 45-54, 55-64, and 65-75 years) were constructed. Analysis of variance, t tests, and regression analyses were used to assess age and gender effects. Results: The response rate was 97 %. There was a significant difference between men and women in scores on all indices and subscales (range p < 0.001 to p = 0.002), except for the upper extremity dysfunction subscale ( p = 0.06). A significant interaction effect was found between gender and age for the upper extremity dysfunction subscale; a larger decrease in score with increasing age was observed for women, compared with men. Significant differences were found between age groups for the bother index ( p < 0.001), lower extremity dysfunction subscale ( p = 0.001), and the problems with daily activities subscale ( p = 0.002). Conclusion: Significant differences in SMFA-NL scores were found between men and women and between different age groups. These SMFA-NL normative data provide an opportunity of benchmarking health status of participants with musculoskeletal disorders or injuries against their age- and gender-matched peers in the Dutch population. [ABSTRACT FROM AUTHOR]

Structure-based drug design (SBDD) is a powerful and widely used approach to optimize affinity of drug candidates. With the recently introduced INPHARMA method, the binding mode of small molecules to their protein target can be characterized even if no spectroscopic information about the protein is known. Here, we show that the combination of the spin-diffusion-based NMR methods INPHARMA, trNOE, and STD results in an accurate scoring function for docking modes and therefore determination of protein-ligand complex structures. Applications are shown on the model system protein kinase A and the drug targets glycogen phosphorylase and soluble epoxide hydrolase (sEH). Multiplexing of several ligands improves the reliability of the scoring function further. The new score allows in the case of sEH detecting two binding modes of the ligand in its binding site, which was corroborated by X-ray analysis. [ABSTRACT FROM AUTHOR]

Structure-based drug design (SBDD) is a powerful and widely used approach to optimize affinity of drug candidates. With the recently introduced INPHARMA method, the binding mode of small molecules to their protein target can be characterized even if no spectroscopic information about the protein is known. Here, we show that the combination of the spin-diffusion-based NMR methods INPHARMA, trNOE, and STD results in an accurate scoring function for docking modes and therefore determination of protein-ligand complex structures. Applications are shown on the model system protein kinase A and the drug targets glycogen phosphorylase and soluble epoxide hydrolase (sEH). Multiplexing of several ligands improves the reliability of the scoring function further. The new score allows in the case of sEH detecting two binding modes of the ligand in its binding site, which was corroborated by X-ray analysis. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVES: Chest trauma is a relevant risk factor for mortality after multiple trauma. Kinetic therapy (KT) represents a potential treatment option in order to restore pulmonary function. Decision criteria for performing kinetic therapy are not fully elucidated. The purpose of this study was to investigate the decision making process to initiate kinetic therapy in a well defined multiple trauma cohort. METHODS: A retrospective analysis (2000-2009) of polytrauma patients (age > 16 years, ISS &NotGreaterSlantEqual; 16) with severe chest trauma (AIS_{Chest} &NotGreaterSlantEqual; 3) was performed. Patients with AIS_{Head} &NotGreaterSlantEqual; 3 were excluded. Patients receiving either kinetic (KT+) or lung protective ventilation strategy (KT-) were compared. Chest trauma was classified according to the AIS_{Chest}, Pulmonary Contusion Score (PCS), Wagner Jamieson Score and Thoracic Trauma Severity Score (TTS). There were multiple outcome parameters investigated included mortality, posttraumatic complications and clinical data. A multivariate regression analysis was performed. RESULTS: Two hundred and eighty-three patients were included (KT+: n=160; KT-: n=123). AIS_{Chest}, age and gender were comparable in both groups. There were significant higher values of the ISS, PCS, Wagner Jamieson Score and TTS in group KT+. The incidence of posttraumatic complications and mortality was increased compared to group KT- (p< 0.05). Despite that, kinetic therapy failed to be an independent risk factor for mortality in multivariate logistic regression analysis. CONCLUSIONS: Kinetic therapy is an option in severely injured patients with severe chest trauma. Decision making is not only based on anatomical aspects such as the AIS_{Chest}, but on overall injury severity, pulmonary contusions and physiological deterioration. It could be assumed that the increased mortality in patients receiving KT is primarily caused by these factors and does not reflect an independent adverse effect of KT. Furthermore, KT was not shown to be an independent risk factor for mortality. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The synthesis and evaluation of two cathepsin S-specific probes is described. For long-term retention of the probe at the target site and a high signal-to-noise ratio, we introduced a lipidation approach via the simple attachment of palmitoic acid to the reporter. After cathepsin S-specific cleavage in cultured cells and in a grafted tumor mouse model, fluorescence increased owing to dequenching and we observed an intracellular accumulation of the fluorescence in the target tissue. The lipidated probe provided a prolonged and strongly fluorescent signal in tumors when compared to the very similar non-lipidated probe, demonstrating that non-invasive tumor identification is feasable. The homing principle by probe lipidation might also work for selective administration of cytotoxic compounds to specifically reduce tumor mass. [ABSTRACT FROM AUTHOR]

The ability to study rare isotopes with techniques such as mass spectrometry and laser spectroscopy is often prevented by low production rates and large isobaric contamination. This has necessitated the development of novel beam cleaning techniques that can efficiently isolate the isotope of interest. The Collinear Resonance Ionization Spectroscopy (CRIS) experiment at ISOLDE, achieves this by resonantly ionizing a bunched atom beam in a region of ultra high vacuum. This method is motivated by the need to measure the hyperfine structure and isotope shift at the extremes of isospin where typical production rates drop to 1 atom/s. The technique also offers the ability to purify an ion beam and even select long-lived isomeric states (> 1 ms) from the ground state, which can be subsequently studied by decay spectroscopy or mass spectrometry experiments. This paper will report on the successful commissioning of the CRIS beam line and the recent laser spectroscopy results and laser assisted nuclear decay spectroscopy on the neutron deficient francium isotopes. [ABSTRACT FROM AUTHOR]

A study on the systematic of the atomic ionization potentials for both, the lanthanide and actinide elements have been performed. The existing experimental basis, predominantly relying on results from resonance ionization spectroscopy, has been extended by novel laser spectroscopic investigations on the elements Au, Dy, Pr and Pa. Conclusive results of suitable precision for the ionization potentials could be obtained except for Pa, due to the complexity of its atomic spectrum. Nevertheless, a consistent interpretation of the observed trends for the ionization potentials of lanthanides and actinides was attempted. The series of lanthanides depicts the two well-known, completely smooth, linear trends above and below half-shell closure, from which an expectation value for the missing ionization potential of the all radioactive element promethium of IP = 44985(140) cm was derived. In contrast, the lighter members of the actinide series below the half-filled shell exhibit a significant deviation from predictions, which are ascribed dominantly to relativistic influences affecting the energetic position of the multitude of low-lying configurations. With the assumption of removal of a 6d electron during the ionization process agreement between theory and experiment and a smooth, even though not linear behavior, is obtained also in this region of the Periodic Table. This new interpretation could help to better predict similar trends and systematics for elements heavier than the actinides. Particularly relevant in this respect are the super-heavy elements, which are produced only in minuscule atom numbers and thus were not accessible for any atomic physics study yet. [ABSTRACT FROM AUTHOR]

Laser spectroscopic investigations on high-lying states around the ionization potential (IP) in the atomic spectrum of Fe have been carried out for the development of a practical three-step resonance ionization scheme accessible by Ti: sapphire lasers. A hot cavity laser ion source, typically used at on-line radioactive ion beam production facilities, was employed in this work. Ionization schemes employing high-lying Rydberg and autoionizing states populated by three-photon excitations were established. Five new Rydberg and autoionizing Rydberg series converging to the ground and to the first four excited states of Fe II are reported. Analyses of the Rydberg series yield the value 63 737.686 ± 0.068 cm−1 for the ionization potential of iron. [ABSTRACT FROM AUTHOR]

Osteoarthritis and rheumatoid arthritis are destructive joint diseases that involve the loss of articular cartilage. Degradation of cartilage extracellular matrix is believed to occur due to imbalance between the catabolic and anabolic processes of resident chondrocytes. Previous work has suggested that various lysosomal cysteine cathepsins participate in cartilage degeneration; however, their exact roles in disease development and progression have not been elucidated. In order to study degradation processes under conditions resembling the in vivo milieu of the cartilage, we cultivated chondrocytes on a type II collagen-containing matrix. Stimulation of the cultivated chondrocytes with interleukin-1α and/or tumor necrosis factor α resulted in a time-dependent increase in cathepsin S expression and induced its secretion into the conditioned media. Using a novel bioluminescent activity-based probe, we were able to demonstrate a significant increase in proteolytic activity of cathepsin S in the conditioned media of proinflammatory cytokine-stimulated chondrocytes. For the first time, cathepsin S was demonstrated to be secreted from chondrocytes upon stimulation with the proinflammatory cytokines, and displayed proteolytic activity in culture supernatants. Its stability at neutral pH and potent proteolytic activity on extracellular matrix components mean that cathepsin S may contribute significantly to cartilage degradation and may thus be considered a potential drug target in joint diseases. [ABSTRACT FROM AUTHOR]

The in-source resonance ionization mass spectrometry technique was applied for quantification of ultratrace amounts of plutonium isotopes as a proof of principle study. In addition to an overall detection limit of 10 to 10 atoms, this method enables the unambiguous identification and individual quantification of the plutonium isotopes Pu and Pu which are of relevance for dating of radiogenic samples. Due to the element-selective ionization process, these isotopes can be measured even under a high surplus of isobaric contaminations from U or Am, which considerably simplifies chemical preparation. The technique was developed, tested, and characterized on a variety of synthetic and calibration samples and is presently applied to analyze environmental samples. [ABSTRACT FROM AUTHOR]

Laser resonance ionization mass spectrometry (RIMS) represents one of the most sensitive and selective techniques for ultra trace determination of long-lived radioisotopes. The isotope Tc constitutes a specific candidate of high relevance concerning its environmental behavior as well as fundamental research applications. Based on the recent precision determination of the ionization potential of technetium by laser resonance ionization, refined resonant optical excitation pathways have been derived for analytical determination of ultra trace amounts of Tc by laser mass spectrometric approaches. The state of the art and the specifications of RIMS-based ultra trace determination for Tc, leading to a level of detection of ε ≈ 3 × 10 atoms (3 μBq), are reported. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The ground-state hyperfine structure of neutral 229Th has been measured for the first time using high-resolution resonance ionization spectroscopy. The measurements were performed as a preparatory work aimed at the identification of the predicted low-lying 7.6 eV isomer in 229Th through an investigation of its hyperfine structure. The hyperfine coupling constants have been extracted for the atomic ground state as well as for three excited states at 26 096, 26 113 and 38 278 cm-1. Due to rather small splittings not all hyperfine components were completely resolved and therefore an extensive X2-error analysis was performed to achieve reliable results. The ground-state transition to the excited state at 38 278 cm-1 was identified to be the most sensitive of the three transitions with regard to the future identification of the isomeric state. [ABSTRACT FROM AUTHOR]