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In this study, we aimed to identify patients within our B-ALL cohort with altered PAX5 . Our objective was to use a comprehensive analysis approach to characterize the types of genetic changes, determine their origin (somatic/germline), and analyze the clinical outcomes associated with them. A consecutive cohort of 99 patients with B-ALL treated at the Children's Hospital of the UMC Ljubljana according to the ALL IC-BFM 2009 protocol was included in our study. We used RNA sequencing data for gene expression analysis, fusion gene detection and single nucleotide variant identification, multiplex-ligation dependent probe amplification for copy number variation assessment, and Sanger sequencing for germline variant detection. PAX5 was impacted in 33.3% of our patients, with the genetic alterations ranging from CNVs and rearrangements to SNVs. The most common were CNVs, which were found in more than a third of patients, followed by point mutations in 5.2%, and gene rearrangements in 4.1%. We identified eight patients with a PAX5 -associated genetic subtype that were previously classified as "B-other", and they showed intermediate outcomes. We showed higher minimal residual disease values at the end of induction and poorer event-free survival in hyperdiploid cases carrying duplications in PAX5 compared to other hyperdiploid cases. We also report an interesting case of a patient with PAX5::FKBP15 and a pathogenic variant in PTPN11 who underwent an early relapse with a monocytic switch. In conclusion, this study provides valuable insights into the presence, frequency, and prognostic significance of diverse PAX5 alterations in B-ALL patients, highlighting the complexity of genetic factors and their impact on patient outcomes.

Determining variant TPMT alleles to predict patient response to thiopurine therapy represents one of the first successful implementations of pharmacogenomics in clinical practice. However, despite the TPMT -adjusted thiopurine dosing, some TPMT wild-type patients still exhibit toxicity at standard doses. Over the past decade, the pharmacogene NUDT15 has emerged as a significant co-modulator of thiopurine therapy. Initially, NUDT15 was considered important predominantly in Asian populations, but recent studies have highlighted its relevance in European populations as well.To evaluate the pharmacogenetic significance of NUDT15 in the Slovenian population, we sequenced extended regions of exon 1 and exon 3 in 109 healthy individuals and 37 patients with acute lymphoblastic leukemia.We identified eight variants, including one with established clinical significance (allele *3) and one extremely rare variant (Chr13 at 48045861; GRCh38, NC_000013.11). The frequencies of most previously described variants in both the general population and in the ALL cohort were consistent with those reported in other European populations, except for rs45465203, which was less frequent in the Slovenian population. None of the variants, except for NUDT15*3 , were associated with cumulative thiopurine doses in ALL patients. However, these variants warrant further investigation in larger ALL cohorts.

The presence of doubly excited states (DESs) above the core-hole ionization threshold nontrivially modulates the x-ray absorption because the participator Auger decay couples DESs to the underlying low-energy core-hole continuum. We show that coupling also affects the high-energy continuum populated by the spectator Auger decay of DESs. For the K-L_{23}^{2} Auger decay of the 1s^{-1}3p^{-1}4s^{2}^{1}P state in argon, the competing nonresonant path is assigned to the recapture of the 1s photoelectron caused by emission of the fast electron from the shake-up K-L_{23}^{2} decay of the 1s^{-1} ion.

Purpose: For working age adults, return to work (RTW) after severe COVID-19 can be an essential component of rehabilitation. We explored the expectations and experiences related to RTW in a group of workers recovering from severe COVID-19 in Slovenia., Materials and Methods: Four focus groups were conducted between May 2021 and August 2021. Fifteen men and three women, aged between 39 and 65 years, participated. We analysed data using reflexive thematic analysis., Results: Four main themes were developed in the analysis, pertaining to (1) work identity, (2) challenges to work re-entry, (3) personal strengths and support systems, and (4) possible adaptations at work. The disruption of work triggered sentiments about its role in identity. Workers' personal agency and self-advocacy helped participants cope with various barriers that were beyond their control, such as physical limitations and lack of systematic routines to address RTW. Workers recovering from severe COVID-19 were at risk of developing negative expectations regarding their work re-entry., Conclusions: RTW after severe COVID-19 involves different personal, organizational and systemic dimensions that need to be considered and carefully aligned. Due to the individuality of the process, the worker should be involved as a key partner in the RTW process.IMPLICATIONS FOR REHABILITATIONLack of clinical pathways can negatively impact return to work (RTW) after severe COVID-19.RTW processes should start early but timely and include individual follow up.Patients expect the interdisciplinary team of experts to work together and involve them in all phases of decision-making regarding their rehabilitation and RTW process.Positive expectations regarding work re-entry are essential for the RTW process.

The authors present and discuss the results of a nation-wide survey on food safety knowledge among professional food handlers in Slovenia. The data were collected via a telephone survey using a well-established questionnaire adapted to the Slovenian context. Altogether, 601 respondents from hotels, restaurants, catering, and confectionery units completed the questionnaire. To assess food safety knowledge among food handlers in both general and specific domains, three indexes (a General Knowledge Index, a Personal Knowledge Index, and a Temperature Knowledge Index) were created. Among them, the Temperature Knowledge Index revealed the largest gaps in knowledge. An insufficient transfer of food safety knowledge from managers and chefs to assistant chefs and kitchen assistants in establishments where more persons handle food was evident, while a course titled "Hygiene Minimum" of standardised training from the past still significantly contributes to food safety knowledge. The results suggest a need for improvement in the current system of food safety training courses for professional food handlers in Slovenia. The human factor in the food supply chain still has a significant role in ensuring food safety culture, and therefore must become a more important part of the food safety management system.

Oral mucositis (OM) is a common side effect in patients undergoing chemotherapy (CT), especially in children due to their rapid epithelial mitotic rate. It has been associated with a significant reduction in life quality since it leads to pain, an inadequate intake of nutrients, an increased risk of opportunistic infections, and interruptions of CT. Photobiomodulation (PMB) with low-level laser therapy (LLLT) has shown faster healing, reduction in pain, and the reduced use of analgesic compared to placebo groups. The purpose of this review is to analyze and compare the existing clinical trials and identify their shortcomings in hope to make future research easier. Using MeSH terms and keywords, the Embase, Medline, and PubMed databases we searched for the period of the last 5 years. We identified a total of 15 clinical trials, with a total of 929 pediatric patients analyzed in this review. We compared different light sources and other laser technique characteristics used in clinical trials such as wavelength, energy and power density, spot size, irradiation time, PBM protocol, and OM evaluation. The main findings show inconsistent laser parameter quotations, differences in the PBM protocol along with a laser application technique, and a lack of clinical trials. Based on that, more studies with a high methodological quality should be conducted in order to provide a unified PBM protocol suitable for the pediatric population.

Pediatric medical traumatic stress (PMTS) is a set of children's and their parents' psychological and physiological responses to pain, injuries, serious illnesses, and other experiences with the medical environment. Pediatric cancer patients have the highest prevalence of PMTS as the illness its treatment involve a set of stressors that trigger many negative psychological reactions. The current study examined the difference in levels of traumatic stress in children with cancer and their parents due to medical factors (type of cancer, outcome, duration, and intensity of treatment, time since diagnosis, relapse, and hospitalization in ICU). The study involved 183 parents of 133 children and 62 children and adolescents who were treated between 2009 and 2019 at the Clinical Department of Pediatric Hematology and Oncology of University Children's Hospital in Ljubljana. We collected the data using The Intensity of Treatment Rating Scale 2.0 [IRT-2], PTSD Checklist for Children/Parent [PCL-C/PR], The PTSD Checklist for DSM-5 [PCL-5] and The Child PTSD Symptoms Scale for DSM-5 [CPSS-5]. Traumatic stress symptoms are frequently present in both children and their parents, regardless of the cancer type, treatment duration, and treatment outcome. Children with relapse, children with more intensive treatment, and parents of the latter are at higher risk for PMTS occurrence. Additionally, we found a decreasing trend of traumatic responses after five or more years post-cancer diagnosis. [Table: see text]., Competing Interests: Conflict of InterestWe have no conflicts of interest to disclose., (© The Author(s), under exclusive licence to Springer Nature Switzerland AG 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)

X-ray Raman spectroscopy (XRS) is an emerging spectroscopic technique that utilizes inelastic scattering of hard X-rays to study X-ray absorption edges of low Z elements in bulk material. It was used to identify and quantify the amount of carbonyl bonds in a cathode sample, in order to track the redox reaction inside metal-organic batteries during the charge/discharge cycle. XRS was used to record the oxygen K-edge absorption spectra of organic polymer cathodes from different multivalent metal-organic batteries. The amount of carbonyl bond in each sample was determined by modeling the oxygen K-edge XRS spectra with the linear combination of two reference compounds that mimicked the fully charged and the fully discharged phases of the battery. To interpret experimental XRS spectra, theoretical calculations of oxygen K-edge absorption spectra based on density functional theory were performed. Overall, a good agreement between the amount of carbonyl bond present during different stages of battery cycle, calculated from linear combination of standards, and the amount obtained from electrochemical characterization based on measured capacity was achieved. The electrochemical mechanism in all studied batteries was confirmed to be a reduction of double carbonyl bond and the intermediate anion was identified with the help of theoretical calculations. X-ray Raman spectroscopy of the oxygen K-edge was shown to be a viable characterization technique for accurate tracking of the redox reaction inside metal-organic batteries., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Background: While deep brain stimulation of the subthalamic nucleus (STN-DBS) significantly improves motor deficits in patients with Parkinson's disease (PD), it is still unclear whether it affects personality functioning., Objective: The objective of the present study was to examine personality changes in patients with PD after STN-DBS from the perspectives of both the patients and caregivers. Moreover, by assessing the premorbid personalities of the patients, we tried to determine individual vulnerability to STN-DBS-induced personality changes., Methods: In total, 27 patients and their caregivers participated in our retrospective observational study. They were asked to assess the patients' personality changes with the Iowa Scale of Personality Changes (ISPC) and the patients' premorbid personalities with the Big Five Inventory (BFI)., Results: Caregivers reported significant personality changes in the ISPC domains of Executive Disturbance (p = 0.01) and Disturbed Social Behavior (p = 0.02). Most of the ISPC domains were positively correlated with Conscientiousness, while Executive Disturbance was negatively correlated with Neuroticism of the BFI scale., Conclusion: Our results show that executive and social functioning are the two most vulnerable domains in patients with PD after STN-DBS, especially in those patients who score higher for neuroticism and lower for conscientiousness on the BFI scale. The results of our study may provide movement disorder specialists with better counseling options and better selection of DBS candidates. Caregivers' perspective might contribute significantly in understanding postoperative personality changes.

Background: Based on the promising results from preclinical studies, bee venom has been investigated as a neuroprotective agent in Parkinson's disease., Objective: To assess if longstanding exposure to bee venom is associated with decreased risk for Parkinson's disease among beekeepers., Methods: Questionnaire gathering information about diagnosis of Parkinson's disease and exposure to bee stings was posted to 6500 members of Slovenian beekeepers' organisation., Results: We received 1298 responses (response rate 20.1%). Twenty beekeepers, all older than 60 years, were diagnosed with Parkinson's disease. The prevalence of Parkinson's disease in beekeepers aged ≥60 years was 3.9%, which is above the reported 0.6-1.3% prevalence of PD in this age group in European population. There was no difference in parameters reflecting bee venom exposure between beekeepers with and without Parkinson's disease., Conclusions: Continuous exposure to bee venom does not affect neurodegeneration to the extent where it could prevent the expression of Parkinson's disease. © 2021 International Parkinson and Movement Disorder Society., (© 2021 International Parkinson and Movement Disorder Society.)

In this work, valence-to-core (VtC) Kβ sulfur X-ray emission spectroscopy (XES) was used to perform quantitative analysis of different sulfur compounds produced in a lithium sulfur (Li-S) battery during discharge. The analysis is based on the theoretical sulfur Kβ XES spectra obtained from ab initio quantum chemical calculations based on density functional theory. The emphasis is given to the Kβ sulfur XES spectra of the polysulfide molecules (Li2Sx, x = 2,,8) produced electrochemically within the Li-S battery. Ab initio molecular dynamics calculations are used further to calculate also the Kβ spectra of Li2Sx dissolved in a model solvent. Calculated spectra were directly compared with the experimental ones collected with a Johansson type tender XES spectrometer on laboratory synthesized Li2Sx reference standards and pre-cycled battery cathodes. These results demonstrate that sulfur VtC XES can be used effectively to quantitatively analyze electrochemical sulfur conversion, also in a smaller laboratory without the need for large scale synchrotron facilities.

A major problem of oral iron supplementation efficacy in children is its tolerability and compliance. We aimed to determine the safety and efficacy of a novel food supplement >Your< Iron Syrup in the replenishment of iron stores and improvement of hematological parameters in iron-deficient children aged nine months to six years. We randomized 94 healthy children with iron deficiency in a ratio of 3:1 to either receive >Your< Iron Syrup or placebo. A 12-week supplementation with >Your< Iron Syrup resulted in a significant increase in ferritin and hemoglobin levels as compared to placebo ( p = 0.04 and p = 0.02). Adverse events were reported with similar frequencies across both study arms. >Your< Iron Syrup represents an effective, well-tolerated, and safe option for the management of nutritional iron deficiency in children.

Application of laboratory-based X-ray analytical techniques that are capable of a reliable characterization of the chemical state of sulfur within bulk battery cathode in parallel with electrochemical characterization is essential for further development of lithium-sulfur batteries. In this work, MeV proton-induced X-ray emission (XES) sulfur measurements were performed in ex situ mode on laboratory-synthesized sulfur standards and precycled battery cathodes. The average sulfur charge was determined from the energy shift of the Kα emission line and from the spectral shape of the Kβ emission spectrum. Finally, operando Kα XES measurements were performed to monitor reduction of sulfur within battery cathode during discharge. The experimental approach presented here provides an important step toward more routine laboratory analysis of sulfur-based battery systems and also other sulfur-neighboring low- Z bulk materials with emission energies in the tender X-ray range., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Vincristine is at the core of many treatment protocols for childhood malignancies. The major dose-limiting side effect is vincristine-induced peripheral neuropathy (VIPN) which may cause morbidity and disrupt curative treatment. Several studies have tried to identify pharmacogenetic biomarkers for susceptibility to vincristine-induced toxicity (Egbelakin A et al., Pediatr Blood Cancer 2011; 56: 361-367. Aplenc R et al., Br J Haematol 2003; 122: 240-244. Diouf B et al., JAMA 2015; 313: 815-823. Zgheib NK et al., Pharmacogenet Genomics , 2018; 28: 189-195. Gutierrez-Camino A et al., Pharmacogenet Genomics 2016; 26: 100-102. Wright GE et al., Clin Pharmacol Ther 2019; 105: 402-410. Kayilioğlu H et al., J Pediatr Hematol Oncol 2017; 39(6): 458-462). A major limitation of these studies is that VIPN is difficult to measure objectively using only clinical examination and clinical scales. This is especially true for children, who are often unable to report or grade symptoms such as paresthesia, numbness, and pain. Furthermore, some studies are questioning the validity of currently available neuropathy grading scales (Postma TJ et al., Ann Oncol 1998; 9: 739-744). Our group recently showed that electrophysiological studies can be used with great accuracy for early detection of VIPN (Kavcic M et al., J Pediatr Hematol Oncol 2017; 39: 266-271). In the previous study, we found that VIPN presents with primary axonal involvement and is more pronounced on motor neurons (Kavcic M et al., J Pediatr Hematol Oncol 2017; 39: 266-271)., Competing Interests: The authors declare that they have no conflict of interest., (Thieme. All rights reserved.)

In a lithium/sulfur (Li/S) battery, the reduction of sulfur during discharge involves a particular mechanism, where the active material successively dissolves into the electrolyte to form lithium polysulfide intermediate species (Li 2 S x ), with x being a function of the state of charge. In this work, sulfur K-edge resonant inelastic X-ray scattering measurements were performed for the characterization of different Li 2 S x polysulfide standard solutions. High-energy resolution fluorescence detected X-ray absorption spectroscopy allowed clear separation the pre-edge absorption peak corresponding to terminal sulfur atoms from the main absorption peak due to internal atoms and allowed quantitative evaluation of the evolution of the peak area ratio as a function of the polysulfide chain length. Results of this experimental work demonstrate that the normalized area of the pre-edge is a reliable fingerprint of the Li 2 S x mean chain length in agreement with recent theoretical predictions. As a perspective, this work confirms that operando HERFD XAS can be used to differentiate mean polysulfide composition, which is key issue in the characterization of Li/S cells.

Aim: We examined the utility of the rs924607 TT genotype of the centrosomal protein 72 ( CEP72 ) as a potential biomarker for predilection toward vincristine-induced peripheral neuropathy in children treated for acute lymphoblastic leukemia., Materials & Methods: We conducted a random-effects meta-analysis of data from four studies comprising 817 patients. We tested for an association using a recessive model where a one-sided p-value < 0.05 was considered statistically significant., Results & Conclusion: We were unable to confirm the association between the rs924607 TT genotype and neurotoxicity (odds ratio: 1.99; p = 0.16; 95% CI: 0.76-5.25) in our global meta-analysis. Analysis of the continuation phase (following induction) studies showed significantly higher odds for neuropathy in CEP72 rs924607 TT homozygotes (odds ratio: 2.28; p = 0.02; 95% CI: 1.16-6.87)., Competing Interests: Financial & competing interests disclosure The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties. No writing assistance was utilized in the production of this manuscript., (© 2020 Aida Zečkanović, Janez Jazbec, Marko Kavčič.)

Stochastic processes are highly relevant in research fields as different as neuroscience, economy, ecology, chemistry, and fundamental physics. However, due to their intrinsic unpredictability, stochastic mechanisms are very challenging for any kind of investigations and practical applications. Here we report the deliberate use of stochastic X-ray pulses in two-dimensional spectroscopy to the simultaneous mapping of unoccupied and occupied electronic states of atoms in a regime where the opacity and transparency properties of matter are subject to the incident intensity and photon energy. A readily transferable matrix formalism is presented to extract the electronic states from a dataset measured with the monitored input from a stochastic excitation source. The presented formalism enables investigations of the response of the electronic structure to irradiation with intense X-ray pulses while the time structure of the incident pulses is preserved.

"Probe-before-destroy" methodology permitted diffraction and imaging measurements of intact specimens using ultrabright but highly destructive X-ray free-electron laser (XFEL) pulses. The methodology takes advantage of XFEL pulses ultrashort duration to outrun the destructive nature of the X-rays. Atomic movement, generally on the order of >50 fs, regulates the maximum pulse duration for intact specimen measurements. In this contribution, we report the electronic structure damage of a molecule with ultrashort X-ray pulses under preservation of the atoms' positions. A detailed investigation of the X-ray induced processes revealed that X-ray absorption events in the solvent produce a significant number of solvated electrons within attosecond and femtosecond timescales that are capable of coulombic interactions with the probed molecules. The presented findings show a strong influence on the experimental spectra coming from ionization of the probed atoms' surroundings leading to electronic structure modification much faster than direct absorption of photons. This work calls for consideration of this phenomenon in cases focused on samples embedded in, e.g., solutions or in matrices, which in fact concerns most of the experimental studies.

We report a case of a 12-year-old male with glucose-6-phosphate dehydrogenase deficiency presenting with clinical signs of sepsis and pancytopenia. Investigations revealed parvovirus B19 (PVB19)-associated hemophagocytic lymphohistiocytosis (HLH). The patient recovered fully and quickly with symptomatic treatment. Current evidence suggests that PVB19-associated HLH has a favorable prognosis. Mild undiagnosed cases of HLH may be the cause of pancytopenia in PVB19 infections.

Competing Interests: The authors declare no conflict of interest., (© Georg Thieme Verlag KG Stuttgart · New York.)

Considerable effort has been devoted to the development of first-row transition-metal catalysts containing redox-active imino-pyridine ligands that are capable of storing multiple reducing equivalents. This property allows abundant and inexpensive first-row transition metals, which favor sequential one-electron redox processes, to function as competent catalysts in the concerted two-electron reduction of substrates. Herein we report the syntheses and characterization of a series of iron complexes that contain both π-donating thiolate and π-accepting (α-imino)-N-heterocycle redox-active ligands, with progressively larger N-heterocycle rings (imidazole, pyridine, and quinoline). A cooperative interaction between these complementary redox-active ligands is shown to dictate the properties of these complexes. Unusually intense charge-transfer (CT) bands, and intraligand metrical parameters, reminiscent of a reduced (α-imino)-N-heterocycle ligand (L •- ), initially suggested that the electron-donating thiolate had reduced the N-heterocycle. Sulfur K-edge X-ray absorption spectroscopic (XAS) data, however, provides evidence for direct communication, via backbonding, between the thiolate sulfur and the formally orthogonal (α-imino)-N-heterocycle ligand π*-orbitals. DFT calculations provide evidence for extensive delocalization of bonds over the sulfur, iron, and (α-imino)-N-heterocycle, and TD-DFT shows that the intense optical CT bands involve transitions between a mixed Fe/S donor, and (α-imino)-N-heterocycle π*-acceptor orbital. The energies and intensities of the optical and S K-edge pre-edge XAS transitions are shown to correlate with N-heterocycle ring size, as do the redox potentials. When the thiolate is replaced with a thioether, or when the low-spin S = 0 Fe(II) is replaced with a high-spin S = 3/2 Co(II), the N-heterocycle ligand metrical parameters and electronic structure do not change relative to the neutral L 0 ligand. With respect to the development of future catalysts containing redox-active ligands, the energy cost of storing reducing equivalents is shown to be lowest when a quinoline, as opposed to imidazole or pyridine, is incorporated into the ligand backbone of the corresponding Fe complex.

A combination of resonant inelastic x-ray scattering and resonant Auger spectroscopy provides complementary information on the dynamic response of resonantly excited molecules. This is exemplified for CH&#95;{3}I, for which we reconstruct the potential energy surface of the dissociative I 3d^{-2} double-core-hole state and determine its lifetime. The proposed method holds a strong potential for monitoring the hard x-ray induced electron and nuclear dynamic response of core-excited molecules containing heavy elements, where ab initio calculations of potential energy surfaces and lifetimes remain challenging.

Background and purpose - The correct diagnosis of prosthetic joint infection (PJI) can be difficult because bacteria form a biofilm on the surface of the implant. The sensitivity of culture from sonication fluid is better than that from periprosthetic tissue, but no comparison studies using molecular methods on a large scale have been performed. We assessed whether periprosthetic tissue or sonication fluid should be used for molecular analysis. Patients and methods - Implant and tissue samples were retrieved from 87 patients who underwent revision operation of total knee or total hip arthroplasty. Both sample types were analyzed using broad-range (BR-) PCR targeting the 16S rRNA gene. The results were evaluated based on the definition of periprosthetic joint infection from the Workgroup of the Musculoskeletal Infection Society. Results - PJI was diagnosed in 29 patients, whereas aseptic failure was diagnosed in 58 patients. Analysis of sonication fluid using BR-PCR detected bacteria in 27 patients, whereas analysis of periprosthetic tissue by BR-PCR detected bacteria in 22 patients. In 6 of 7 patients in whom BR-PCR analysis of periprosthetic tissue was negative, low-virulence bacteria were present. The sensitivity and specificity values for periprosthetic tissue were 76% and 93%, respectively, and the sensitivity and specificity values for sonication fluid were 95% and 97%. Interpretation - Our results suggest that sonication fluid may be a more appropriate sample than periprosthetic tissue for BR-PCR analysis in patients with PJI. However, further investigation is required to improve detection of bacteria in patients with so-called aseptic failure.

We present a theoretical and experimental study of resonant inelastic x-ray scattering on a large group of chlorinated hydrocarbons: CH3Cl, CH2Cl2, CHCl3, CCl4, CH3CH2Cl, ClCH2CH2Cl, CH3CHCl2, CH3CCl3, C2H2Cl2-iso, C2H2Cl2-cis, C2H2Cl2-trans, and C6H5Cl. Differences in structural and dynamical properties of the molecules generated by diverse chemical environments are observed in the measured Cl(K(α)) spectral maps as well as in the Cl(K) total fluorescence yield spectra. The energy position, relative intensity, and the width of the Franck-Condon distribution of low-lying σ* and π* resonances are extracted by a fitting procedure taking into account the experimental broadening. The theoretical values obtained with the transition potential and Δ Kohn-Sham methods are in good agreement with the experimental parameters indicating subtle differences due to variations in the molecular structure.

In this paper we report an X-ray emission study of bulk aqueous sulfuric acid. Throughout the range of molarities from 1 M to 18 M the sulfur Kβ emission spectra from H2SO4 (aq) depend on the molar fractions and related deprotonation of H2SO4. We compare the experimental results with results from emission spectrum calculations based on atomic structures of single molecules and structures from ab initio molecular dynamics simulations. We show that the S Kβ emission spectrum is a sensitive probe of the protonation state of the acid molecules. Using non-negative matrix factorization we are able to extract the fractions of different protonation states in the spectra, and the results are in good agreement with the simulation for the higher part of the concentration range.

Background: Undiagnosed low-grade prosthetic joint infections (PJI) are recognized as an important reason for early failure of presumably aseptic revisions. Preoperatively administered antimicrobial prophylaxis reduces the incidence of PJI but it may reduce the sensitivity of microbiologic periprosthetic tissue cultures and consequently increase the incidence of undiagnosed septic prosthetic joint failures, which can lead to catastrophic serial revisions., Questions/purposes: We wished to determine whether administration of preoperative antibiotics decreases the likelihood of diagnosing PJI in patients undergoing revision hip or knee arthroplasty in whom infection is suspected., Methods: We prospectively enrolled and evaluated 40 patients (29 with THAs and 11 with TKAs) who met the following inclusion criteria: older than 18 years, with suspected PJI of unknown cause, undergoing surgical revision. After arthrotomy, three tissue samples were obtained for microbiologic analysis and diagnosis, and antimicrobial prophylaxis (cefazolin 2 g intravenously) then was administered. Later during the procedure, but before débridement and irrigation, the second set of three tissue samples was obtained from the same surgical area and was cultured. Tissue concentration of prophylactic antibiotic was verified with the second set of samples. A positive culture result was defined as one or more positive cultures (growth on agar at or before 14 days). We then compared the yield on the microbiologic cultures obtained before administration of antibiotics with the yield on the cultures obtained after antibiotics were administered. An a priori analysis was performed; with the numbers available, we had 98% power to detect a difference in diagnostic sensitivity of 33%., Results: With the numbers available, we found no difference in the likelihood that an infection would be diagnosed between the samples obtained before and after administration of antimicrobial prophylaxis (odds ratio [OR] for positive microbial culture = 0.99; 95% CI, 0.40-2.48; p = 0.99). All measured tissue concentrations of cefazolin were greater than the minimum inhibitory concentration, therefore we found that antibiotic prophylaxis was adequate at the time of second-set tissue specimen recovery., Conclusions: Results from this small, prospective series suggest that preoperative antimicrobial prophylaxis may be administered safely even in patients undergoing revision hip or knee arthroplasty in which microbiologic sampling is planned without compromising the diagnostic sensitivity of tissue sample cultures. However, before applying our results more generally, our findings need to be confirmed in larger, multicenter studies that would allow evaluation by sex, procedure, bacteriology, and other potentially important factors., Level of Evidence: Level I, diagnostic study.

An experimental and theoretical study of phosphorus electronic structure based on high energy resolution X-ray emission spectroscopy was performed. The Kα and Kβ emission spectra of several phosphorus compounds were recorded using monochromatic synchrotron radiation and megaelectronvolt (MeV) proton beam for target excitation. Measured spectra are compared to the results of ab initio quantum chemical calculations based on density functional theory (DFT). Clear correlation between energy position of the Kα emission line and the phosphorus formal oxidation state as well as DFT-calculated number of valence electrons is obtained; measured energy shifts are reproduced by the calculations. Chemical sensitivity is increased further by looking at the Kβ emission spectra probing directly the structure of occupied molecular orbitals. Energies and relative intensities of main components are given together with the calculated average atomic character of the corresponding molecular orbitals involved in transitions.

Purpose: Prosthetic joint infection (PJI) is a devastating complication of total joint arthroplasty. No single laboratory test has perfect sensitivity and specificity; however, culture of periprosthetic tissue is the standard method for PJI diagnosis. Interpretation of positive culture results in PJI diagnostics can be difficult due to the possibility of contamination with microorganisms originating from skin micro flora. Criteria have been established to aid in distinguishing pathogen from contaminant for culture results. A similar criterion has not however been established for polymerase chain reaction (PCR) analysis, which is in part responsible for confusion about the reliability of PCR for PJI diagnostics. The aim of our study was to establish a criterion for interpretation of broad range (BR) PCR results in PJI diagnostics., Methods: Samples of periprosthetic tissue were retrieved from 100 patients with joint prosthesis failure and analysed with BR-PCR. The results of BR-PCR were evaluated based on the number of samples of periprosthetic tissue with the same bacterial species., Results: The sensitivity (87.5%) of BR-PCR was highest if the same species was present in at least one sample, although this criterion also resulted in the lowest specificity (92.1%). The sensitivity decreased (83.2%), although without a statistically significant difference, if the same species was present in two or more samples but, at the same time, specificity increased (100%), with a statistically significant difference., Conclusions: For diagnostics of PJI with BR-PCR the criterion of the same bacterial species in at least two specimens of periprosthetic tissue from the same patient should be used for interpretation of positive results.

Seeded free electron lasers theoretically have the intensity, tunability, and resolution required for multiphoton spectroscopy of atomic and molecular species. Using the seeded free electron laser FERMI and a novel detection scheme, we have revealed the two-photon excitation spectra of dipole-forbidden doubly excited states in helium. The spectral profiles of the lowest (-1,0)(+1) (1)S(e) and (0,1)(0) (1)D(e) resonances display energy shifts in the meV range that depend on the pulse intensity. The results are explained by an effective two-level model based on calculated Rabi frequencies and decay rates.

We report a theoretical and experimental study of the high resolution resonant K(α) X-ray emission lines around the chlorine K-edge in gas phase 1,1-dichloroethylene. With the help of ab initio electronic structure calculations and cross section evaluation, we interpret the lowest lying peak in the X-ray absorption and emission spectra. The behavior of the K(α) emission lines with respect to frequency detuning highlights the existence of femtosecond nuclear dynamics on the dissociative Potential Energy Surface of the first K-shell core-excited state.

A theoretical analysis of dissociation dynamics of chlorine K-σ(*) core-excited molecules is performed. The potential energy surfaces of HCl, Cl2, CH3Cl, CH2Cl2, CHCl3, CCl4, CFCl3, CF2Cl2, and CF3Cl are calculated along the normal vibrational modes of the ground electronic state yielding the widths of the corresponding Franck-Condon distributions. An insight into the potential energy surface of 1st σ(*) resonances shows that the initial dissociation dynamics of chloro(fluoro)methanes mainly involves the distancing of the carbon and the core-excited chlorine atom and is practically independent of other atoms in the molecule, which is in agreement with the recent experimental findings. The carbon atom pulls out the remaining three atoms shortly after piercing the three-atom plane resulting in a high vibrationally excited state of the fragment if the reconnection time is smaller than the lifetime of the L shell.

The dissociation process following the Cl K-shell excitation to σ* resonances is studied by high resolution spectroscopy of resonant elastic and inelastic x-ray scattering on CH3Cl, CH2Cl2, CHCl3, and CCl4 molecules. Calculations employing the transition potential and Delta-Kohn-Sham DFT approach are in good agreement with the measured total fluorescence yield and show the presence of a second quasidegenerate group of states with σ* character above the lowest σ* unoccupied molecular orbital for molecules with more than one Cl atom. A bandwidth narrowing and a nonlinear dispersion behavior is extracted from the Kα spectral maps for both σ* resonances. The fitted data indicate that the widths of the Franck-Condon distributions for the first and second σ* resonances are comparable for all the molecules under study. In addition, an asymmetric broadening of the emission peaks is observed for resonant elastic x-ray scattering with zero detuning on both σ* resonances. This is attributed to the fast dissociation, transferring about 0.15 of the scattering probability into higher vibrational modes.

Non-magnetic Pt catalysts, supported on carbon coated magnetic Co nanoparticles, changed catalytic performance in the presence of an external magnetic field. This behavior relates to an electronic change of Pt induced by a localized magnetic field, which modifies the CO adsorption geometry. In situ resonant inelastic X-ray scattering (RIXS) experiments and theory reveal the change of atop CO adsorption geometry on the Pt catalyst to bridged geometry under an external magnetic field. This observation opens the possibility of catalytic control by means of an external magnetic field.

Diagnosis of prosthetic joint infection with culture technique can be problematic since the causative agent(s) are not possible to cultivate in all cases. Molecular methods had been evaluated in many studies but their inclusion in routine diagnostics is still controversial. The purpose of our prospective study was to compare the diagnostic accuracy of broad-range (BR)-PCR and culture technique. Intraoperative samples of periprosthetic tissue were retrieved in 67 patients undergoing revision arthroplasty. Samples were analyzed with culture technique, immunohistochemistry and BR 16S rRNA gene PCR. Bacteria in PCR-positive samples were identified using two different methods: direct sequencing of PCR products and specific TaqMan assays. In 63 cases, full concordance was found between BR-PCR and culture technique. Specific TaqMan assays failed to identify bacteria in four culture- and BR-PCR-positive cases and therefore had a lower sensitivity in comparison with BR-PCR. Molecular methods detected bacteria with the same accuracy as culture; however, identification of bacteria was inferior to culture. Further development of species-recognition techniques is required to improve identification of causative microorganisms., (© 2013 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.)

The electrical resistivity of amorphous Fe(100-x)Zr(x) metal alloy films and multilayers has been investigated in a wide temperature and composition range. The overall behavior of the resistivity is consistent with bulk measurements, exhibiting prominent semiconductor-like changes at low temperatures. The transition from positive (metallic) to negative temperature coefficient of resistivity behavior is accompanied by minute changes in magnetoresistance and we can therefore rule out magnetic phase changes as being the cause for the observed changes in the resistivity. Using x-ray absorption and emission spectroscopies we are able to probe the unoccupied and occupied electronic densities of states. The corresponding spectra are found to significantly overlap, as expected for a metallic-like electronic structure and the absence of a band gap. Besides a broadening of the x-ray emission lines expected from an amorphous material, remarkably small differences are observed in the electronic structures when changing the amount of Zr. The resistivity data were modeled and agreement with the Mott variable range hopping model was found, indicating localized electronic states due the disordered structure of the Fe(100-x)Zr(x) alloys.

A complete in-vacuum curved-crystal x-ray emission spectrometer in Johansson geometry has been constructed for a 2-6 keV energy range with sub natural line-width energy resolution. The spectrometer is designed to measure x-ray emission induced by photon and charged particle impact on solid and gaseous targets. It works with a relatively large x-ray source placed inside the Rowland circle and employs position sensitive detection of diffracted x-rays. Its compact modular design enables fast and easy installation at a synchrotron or particle accelerator beamline. The paper presents main characteristics of the spectrometer and illustrates its capabilities by showing few selected experimental examples.

Experimental evidence for the correlated two-electron one-photon transitions (1s(-2)→2s(-1)2p(-1)) following single-photon K-shell double ionization is reported. The double K-shell vacancy states in solid Mg, Al, and Si were produced by means of monochromatized synchrotron radiation, and the two-electron one-photon radiative transitions were observed by using a wavelength dispersive spectrometer. The two-electron one-photon transition energies and the branching ratios of the radiative one-electron to two-electron transitions were determined and compared to available perturbation theory predictions and configuration interaction calculations.

We present measurements of the resonant inelastic x-ray scattering (RIXS) spectra of the CH(3)I molecule in the hard-x-ray region near the iodine L(2) and L(3) absorption edges. We show that dispersive RIXS spectral features that were recognized as a fingerprint of dissociative molecular states can be interpreted in terms of ultrashort natural lifetime of ∼200 attoseconds in the case of the iodine L-shell core-hole. Our results demonstrate the capacity of the RIXS technique to reveal subtle dynamical effects in molecules with sensitivity to nuclear rearrangement on a subfemtosecond time scale.