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Alpine swifts (Tachymarptis melba) are sub-Saharan migratory birds, which, in Switzerland, nest in colonies that have been continuously monitored for over 40 years. In the summer of 2022, despite favourable environmental conditions, an unexpectedly high number of sudden mortalities (30–80%) occurred in 20 to 45-day-old nestlings from several nesting sites, of which 3 were monitored in detail. Nestlings submitted for post-mortem analysis (n = 5) were in good body condition but exhibited extensive subcutaneous haematomas (n = 5), myocardial petechiae (n = 2) and stunted growth of primary feathers (n = 1). In all birds, 4–5 μm large, amastigote-like protozoans were identified in skeletal and cardiac muscle sections. These tissues tested positive in a PCR targeting the 18S-rRNA gene of Trypanosoma spp. Amplified sequences showed 99.63% identity with sequences of Trypanosoma corvi (JN006854 and AY461665) and Trypanosoma sp. (AJ620557, JN006841). 72 blood smears of 45-day-old nestlings from two colonies were assessed, of which 20 contained trypomastigote forms, some with high parasitaemia (highest average of 56.4 in 10 high power fields, 400x magnification). Trypomastigote morphometrics (n = 36; mean total length = 30.0 μm; length of free flagellum = 5.8 μm) were consistent with those of T. bouffardi. These findings suggest that an avian trypanosomiasis causing mass nestling mortality could be an emerging disease in Swiss Alpine swift populations. [Display omitted] • High Alpine swift nestling mortalities were observed across numerous Swiss colonies. • Amastigote-like forms were observed in skeletal muscle, cardiac and adipose tissues. • High trypomastigote burdens were identified on blood smears. • Emerging avian trypanosomiasis has been identified as the most likely cause of mortality. [ABSTRACT FROM AUTHOR]

Cell-derived matrices (CDMs) provide an exogenous source of human extracellular matrix (ECM), with applications as cell delivery vehicles, substrate coatings for cell attachment and differentiation, and as biomaterial scaffolds. However, commercial application of CDMs has been hindered due to the prolonged culture time required for sufficient ECM accumulation. One approach to increasing matrix deposition in vitro is macromolecular crowding (MMC), which is a biophysical phenomenon that limits the diffusion of ECM precursor proteins, resulting in increased ECM accumulation at the cell layer. Hyaluronic acid (HA), a natural MMC highly expressed in vivo during fetal development, has been shown to play a role in ECM production, but has not been investigated as a macromolecule for increasing cell-mediated ECM deposition in vitro. In the current study, we hypothesized that HA can act as a MMC, and increase cell-mediated ECM production. Human dermal fibroblasts were cultured for 3, 7, or 14 days with 0%, 0.05%, or 0.5% high molecular weight HA. Ficoll 70/400 was used as a positive control. SDS-PAGE, Sircol, and hydroxyproline assays indicated that 0.05% HA-treated cultures had significantly higher mean collagen deposition at 14 days, whereas Ficoll 70/400-treated cultures had significantly lower collagen production compared to the HA and untreated controls. However, fluorescent immunostaining of ECM proteins and quantification of mean gray values did not indicate statistically significant differences in ECM production in HA or Ficoll 70/400-treated cultures compared to untreated controls. Raman imaging (a marker-free spectral imaging method) indicated that HA increased ECM deposition in human dermal fibroblasts. These results are consistent with decreases in CDM stiffness observed in Ficoll 70/400-treated cultures by atomic force microscopy. Overall, these results indicate that there are macromolecule- and cell type- dependent effects on matrix assembly, turnover, and stiffness in cell-derived matrices. Cell-derived matrices (CDMs) are versatile biomaterials with many regenerative medicine applications, including as cell and drug delivery vehicles and scaffolds for wound healing and tissue regeneration. While CDMs have several advantages, their commercialization has been limited due to the prolonged culture time required to achieve CDM synthesis in vitro. In this study, we explored the use of hyaluronic acid (HA) as a macromolecular crowder in human fibroblast cell cultures to support production of CDM biomaterials. Successful application of macromolecular crowding will allow development of human cell-derived, xeno-free biomaterials that re-capitulate the native human tissue microenvironment. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• Validated multi-step simulation strategy from LSP process to fatigue crack growth. • Precise prediction of the FCP-rate based on macroscopic residual stress alone. • Application of numerically predicted crack driving quantities to unpeened specimens. • Introduction of crack driving, applied and residual stress intensity factor. • Demonstration of an efficient LSP-induced residual stress prediction. Laser shock peening (LSP) is a promising technology to retard the fatigue crack propagation (FCP) in metallic lightweight structures. A multi-step simulation strategy to predict FCP in LSP-induced residual stress fields is proposed and applied. The simulation strategy involves an LSP process simulation, a transfer approach to include the plastic strains in a C(T) specimen model to calculate the residual stresses and an FCP simulation to determine the stress intensity factors. The FCP rate is finally determined via FCP equations. The validity of the simulation strategy including the crack driving quantities prediction is experimentally demonstrated by a novel 'simulation' approach. [ABSTRACT FROM AUTHOR]

In vitro cultured cells produce a complex extracellular matrix (ECM) that remains intact after decellularization. The biological complexity derived from the variety of distinct ECM molecules makes these matrices ideal candidates for biomaterials. Biomaterials with the ability to guide cell function are a topic of high interest in biomaterial development. However, these matrices lack specific addressable functional groups, which are often required for their use as a biomaterial. Due to the biological complexity of the cell-derived ECM, it is a challenge to incorporate such functional groups without affecting the integrity of the biomolecules within the ECM. The azide-alkyne cycloaddition (click reaction, Huisgen-reaction) is an efficient and specific ligation reaction that is known to be biocompatible when strained alkynes are used to avoid the use of copper (I) as a catalyst. In our work, the ubiquitous modification of a fibroblast cell-derived ECM with azides was achieved through metabolic oligosaccharide engineering by adding the azide-modified monosaccharide Ac 4 GalNAz (1,3,4,6-tetra-O-acetyl-N-azidoacetylgalactosamine) to the cell culture medium. The resulting azide-modified network remained intact after removing the cells by lysis and the molecular structure of the ECM proteins was unimpaired after a gentle homogenization process. The biological composition was characterized in order to show that the functionalization does not impair the complexity and integrity of the ECM. The azides within this “ click ECM” could be accessed by small molecules (such as an alkyne-modified fluorophore) or by surface-bound cyclooctynes to achieve a covalent coating with click ECM. Statement of Significance The click ECM was produced by the incorporation of azide-functionalized sugar analogues into the extracellular glycans of fibroblast cell cultures by metabolic oligosaccharide engineering. By introducing these azide groups into the glycan structures, we enabled this cell-derived ECM for bioorthogonal click reactions. Click chemistry provides extremely specific reactions with high efficiency, high selectivity, and high reaction yields. We could show that the azide functionalities within the click ECM are chemically accessible. Based on our here described click ECM technique it will be possible to create and investigate new clic kECM materials with tunable bioactive properties and additional functionalities, which offers a promising approach for basic and applied research in the field of biomaterial science, biomedical applications, and tissue engineering. [ABSTRACT FROM AUTHOR]

Rationale: Difficult vascular access (DVA) is a common problem. Placement of ultrasound-guided standard length catheters (ultrasound-guided peripheral intravenous [USPIV]) in the internal jugular (IJ) vein is a potential solution.Objectives: The objective of the study is to evaluate the immediate and short-term incidence of complications after USPIV placement in IJ of DVA patients.Methods: We conducted a prospective convenience study of USPIV into IJ of emergency department patients with DVA. All USPIV placements were performed with standard aseptic techniques with either an 18-gauge 6.35-cm single-lumen catheter or 20-gauge 5.7-cm catheter. Immediate complications were evaluated. Clinical follow-up consisted of review of the electronic medical record for physician and nursing documentation, laboratory data, and imaging studies in a multiple hospital network. Outcome measures 1 and 6 weeks included local site abnormalities, bleeding, local or systemic infection, pneumothorax, or thrombosis at time of placement, and death.Results: We enrolled 33 patients (58% female; mean age, 56.4 years; and median body mass index of 24.7). Eleven physicians performed USPIV placement. Median access time was 4.0 (interquartile range, 5.5) minutes and 1 attempt for placements. There were no immediate complications. Follow-up was successful in 5 of 7 discharged patients and 26 of 27 admitted patients. Three deaths within 6 weeks were unrelated to USPIV. Three patients lost to follow-up were not discovered on electronic medical record or death registries. No patient had catheter-related complications.Conclusions: There were no immediate or short-term complications associated with aseptic USPIV placement into IJ. Ultrasound-guided peripheral intravenous IJ placement was a rapid and safe approach in DVA patients. [ABSTRACT FROM AUTHOR]

Abstract: The application of the RCT-concept for predicting the removal of trace organic compounds (TrOCs) in organic rich WWTP effluents is often problematic due to the fast ozone depletion with instantaneous ozone demand in the range of typically applied ozone dosages. In this study, the determination of OH-radical and ozone exposure from second order rate kinetics with two internal tracer substances was evaluated as alternative approach for these waters. Results from batch and semi-batch experiments showed a linear correlation of OH-radical exposure with ozone consumption, characterized by its slope indicating the formation efficiency of OH-radicals and a lag ozone consumption without significant formation of OH-radicals. Evaluation of data from the project PILOTOX on ozonation of secondary effluent confirmed reasonable prediction of ozone resistant compound removal from relative residual concentration of an internal tracer substance. In contrast, predicting the reduction of TrOCs by direct reactions with ozone from internal tracers was not feasible. Similar removal efficiencies for fast reacting compounds with different rate constants from kO3 = 104 M−1 s−1 to kO3 = 106 M−1 s−1 were observed indicating a limitation of the reaction by mass transfer. This effect was observed at low ozone dosages in semi-batch and pilot experiments as well as in batch experiments, where mass transfer from gas to liquid phase is not limiting. It is assumed that consumption of low ozone dosages is faster than sample homogenization in the batch reactors used. Thus, prediction of compound removal by direct reaction with ozone always needs to consider reactor design and geometry. [Copyright &y& Elsevier]

Abstract: Currently leading crystalline solar cell technologies comprehend rear side passivation with local aluminium back surface field and dielectric reflection layer. For this purpose Centrotherm developed the centaurus technology, which is based on a rear side dielectric passivation and local aluminium BSF (LBSF) in combination with a laser diffused selective front side emitter. A major aspect of the developed technology is its compatibility for an upgrade of existing Al-BSF cell production lines and for turnkey lines as well. Moreover, the equipment required for the new technology is merely based on familiar technologies like wet etching, PECVD layer deposition, laser processing and screen printing. This conformity with common technologies and the simplicity and sustainability of their production implementation as well as the exceptional high cell efficiencies in production favour the new centaurus technology.In production average cell efficiencies well over 19% have been achieved and best cell efficiencies of 19.6% were reached. Under laboratory conditions average cell efficiencies of module ready centaurus solar cells with rear side Ag pads reached 19.7%, with best cell efficiencies up to 19.9%. These results clearly indicate that the centaurus technology is approaching module ready solar cell efficiencies of 20%. Assembled modules demonstrate the excellent power conversion of the centaurus solar cells. First environmental tests have been successfully passed. [Copyright &y& Elsevier]

Abstract: For an improved solar cell performance rear side passivation and local contacts in combination with a laser diffused selective emitter were developed and cell efficiencies up to 19.5% were reached. Several fundamental physical impacts of major importance, such as the light trapping behaviour because of specific surface preparations, the resulting passivation performance, the interaction of emitter and rear surface recombination currents, were investi-gated. In the first test runs in a production environment average solar cell efficiencies of 18.6% and best cell efficiencies of 19.0% were successfully achieved under non-adapted production conditions. [Copyright &y& Elsevier]

Abstract: With the objective of high efficiency solar cells rear side passivation with local aluminium back surface field and dielectric reflection (Al-LBSFR) were developed at Centrotherm and cell efficiencies of 19.4% were achieved. In this paper major physical properties of the developed technology, named centaurus technology, are presented. A low reflection on the solar cell front side is achieved by a textured surface, which enables in particular an inclined light entry at the solar cell front side, which is mandatory for a total light reflection on the solar cell dielectric rear side. Likewise a smooth instead of a textured rear side surface was more suitable for a high rear reflection and also more appropriate for better rear surface passivation. In addition, the influence of the rear side local BSF and metallization fraction was identified as a possible Voc limitation in combination with the front emitter saturation currents. Lower temperature coefficients of the cell power output or cell efficiency and of the open circuit voltage were evaluated for Al-LBSFR cells. [Copyright &y& Elsevier]

Abstract: A convenient and rapid procedure has been achieved to immobilize densely packed nanoporous 3D arrays of oleic acid (OLEA)-capped rod-shaped TiO2 nanocrystals (NCs) and nearly spherical Fe2O3 NCs on the surface of micro mechanical cantilever sensors on SU-8. The NCs have been immobilized at room temperature and in the dark on the micro cantilevers before their release. AFM, SEM and XPS investigations attest for an effective and attachment of the NCs on the SU-8 which occurs with not modifying the original morphology and chemical composition of the nano-objects allowing for an effective accomplishment of the cantilever fabrication. [Copyright &y& Elsevier]

OBJECTIVE: To investigate the effectiveness of a TTM-based motivational counselling approach by trained practice nurses to promote physical activity of low back pain patients in a German primary care setting. METHODS: Data were collected in a cluster-randomized controlled trial with three study arms via questionnaires and patient interviews at baseline and after 6 and 12 months. We analysed total physical activity and self-efficacy by using random effect models to allow for clustering. RESULTS: A total of 1378 low back pain patients, many with acute symptoms, were included in the study. Nearly 40% of all patients reported sufficient physical activity at baseline. While there were significant improvements in patients' physical activity behaviour in all study arms, there was no evidence for an intervention effect. CONCLUSION: The outcome may be explained by insufficient performance of the practice nurses, implementation barriers caused by the German health care system and the heterogenous sample. PRACTICE IMPLICATIONS: Given the objective to incorporate practice nurses into patient education, there is a need for a better basic training of the nurses and for a change towards an organizational structure that facilitates patient-nurse communication. Counselling for low back pain patients has to consider more specificated aims for different subgroups. [ABSTRACT FROM AUTHOR]

Exosomes are small membrane vesicles that are secreted from a variety of cell types into various body fluids including the blood and urine. These vesicles are thought to play a role in cell–cell interactions. CD24 is a small but extensively glycosylated protein linked to the cell surface by means of a glycosyl-phosphatidylinositol anchor. In this study we found that CD24 is present in membrane vesicles characterized as exosomes that were isolated from the urine of normal individuals. CD24 was expressed by both tubule cells and podocytes and treatment of the latter with a cholesterol-extracting agent, but not with a calcium ionophore, caused the release of CD24-containing exosomes. Using CD24 as a marker, we found exosomes in the urine of newborn infants and in the amniotic fluid of pregnant women with similar findings made in mice. Interestingly, studies with CD24 knockout mice showed that the exosomes are released from the fetus but not from the mother; however, exosome release was similar from both the knockout and the wild-type mice. This indicates that CD24 is not essential for exosome formation or release but may be a convenient exosome marker. Our studies suggest that exosomal secretion from the embryonic kidney could play a biological role at the fetal–maternal interphase.Kidney International (2007) 72, 1095–1102; doi:10.1038/sj.ki.5002486; published online 15 August 2007 [ABSTRACT FROM AUTHOR]

Bone tumours are rare and should be assessed and treated in specialized centres. Clinical staging uses various imaging techniques; pathological grading requires tumour biopsy following clinical staging. Surgery remains the mainstay of treatment for musculoskeletal tumours. The surgical margin describes the extent of the procedure, with marginal excision referring to a procedure that removes the tumour alone. Radical margins may require removal of the entire bone/compartment. Open incisional biopsy is the gold standard method for obtaining a representative specimen of tumour. Careful planning and good collaboration is crucial between surgeons, radiologists, and pathologists in order to prevent unnecessary morbidity. The aims of the bone tumour surgeon are to improve survival and maintain optimal function of the patient. This can potentially be achieved by amputation or limb salvage. Currently, limb salvage provides no greater risk to the survival of the patient compared to amputation. Reconstruction after excision of the tumour can be achieved by using endoprosthetic replacements, autografts, or massive allografts. Major complications of limb salvage include infection and difficulties associated with soft tissue re-attachment and coverage of the prosthesis. [ABSTRACT FROM AUTHOR]

• Clarification of stress intensity factor superposition under crack closure phenomena. • Importance of crack geometry changes by crack closure for stress intensity factor superposition is demonstrated. • Proposal and discussion of two alternative residual and applied stress intensity factor definitions. • Discussion of crack face contact modelling for stress intensity factor calculation in fatigue load cycles. The correlation between stress intensity factor (SIF) range and fatigue crack growth is a powerful tool for fail-safe design approaches applied to lightweight structures. The key role is precise calculation of the SIFs of fatigue load cycles. Advanced material processing can shape residual stresses and makes SIF calculation a challenging task. While the consideration of tensile residual stresses is successfully tackled by SIF superposition, the treatment of compressive residual stresses needs still clarification. This work demonstrates the application of the SIF superposition principle in regions containing high compressive residual stresses leading to crack closure effects. Crack closure depends on the combined load of residual and applied stresses and is interpreted as a change of crack geometry in this work. Thus the relation between the source, i.e. the applied or residual stress, and its consequence, i.e. the corresponding SIFs, depends on the interaction of the sources, i.e. the combined load. Due to this interaction, residual stress-induced changes of the fatigue behaviour cannot be linked to the residual or applied SIF only. This work proposes two alternative definitions of applied and residual SIF, allowing a clear correlation between either residual or applied SIF to fatigue behaviour changes. [ABSTRACT FROM AUTHOR]

• Identification of crack closure as important mechanism to retard FCP. • Interpretation of the FCP rate considering stress intensity factors and crack closure. • Numerical and experimental results of crack closure areas agree very well. • Crack closure does not necessarily cause a zero value stress intensity factor. • Fast prediction of FCP rates by stress intensity factor vs. applied load curves. Laser shock peening (LSP) is successfully applied to retard fatigue cracks in metallic lightweight structures by introducing specific, in particular compressive, residual stress fields. In this work, experiments and a multi-step simulation strategy are used to explain the fatigue crack retarding and accelerating mechanisms within these LSP-induced residual stress fields. Crack face contact is identified as main mechanism to retard the fatigue crack as the stress distribution changes and the stress intensity factor range decreases. Crack face contact is experimentally detected by load vs. crack opening displacement (COD) curves and scanning electron microscopy (SEM) of the crack faces, as well as during numerical simulations. The convincing agreement between experiment and simulation, especially regarding the specific crack face contact areas, allowed the proper evaluation of the stress intensity factors depending on the crack length. It is found that crack closure is indeed one of the main reasons for the efficient application of LSP for fatigue crack retardation. Furthermore, the occurrence of crack closure does not indicate a zero value stress intensity factor in complex residual stress fields, as the areas of crack face contact depend strongly on the LSP-induced compressive residual stresses. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the benefit of extracellular gadolinium-based contrast agent (GBCA) enhanced magnetic resonance imaging (MRI) in addition to conventional non-enhanced T2-weighted imaging (WI) for quantification of inflammatory or fibrotic alterations in the liver parenchyma of patients with primary sclerosing cholangitis (PSC).Material and Methods: MRI (3 T) examinations were reviewed retrospectively by two radiologists in 27 PSC patients (age 42.9±15.6 years), and 19 controls. Regions of interest (ROIs) were drawn onto T2 hyperintense and T2 isointense areas and copied to section position matched non-enhanced and delayed-phase contrast-enhanced T1WI. Signal intensities (SI) obtained from ROIs of the multiphase T1WI were used to calculate relative liver enhancement (RLE). The interobserver agreement of RLE and quantified T2 signal was calculated using Bland-Altman analysis. RLE assessed for both T2 hyperintense (RLEhyper) and T2 isointense (RLEiso) areas were compared in patients and controls (RLEhealthy).Results: The interobserver agreement of RLE in affected hyperintense areas (bias -0.77, limits of agreement -51.7 to 50.1) was superior to the quantification of T2 signal only in these areas (bias -3.35, limits of agreement -162.4 to 155.7). The RLEhyper (86.2±9.7%) was higher than the RLEiso (59.8±6.2%, p=0.03) and the RLEhealthy (53.2±2.7%, p=0.002). The mean RLEiso was not significantly different from the RLEhealthy (p=0.3).Conclusion: The extracellular gadolinium-based RLE of T2 hyperintense areas could be a useful add-on for routine follow up MRI in the detection of early inflammatory changes, possibly preceding formation of fibrotic scarring in PSC patients, if validated in larger cohorts. [ABSTRACT FROM AUTHOR]