Distinct Serum GFAP and Nf-L Time-Courses after Rapid Head Rotations

Traumatic brain injury (TBI) causes significant neurophysiological deficits and is typically associated with rapid head accelerations common in sports-related incidents and automobile accidents. There are over 1.5 million TBIs in the US each year, with children aged 0-4 being particularly vulnerable. TBI diagnosis is currently achieved through interpretation of clinical signs and symptoms and neuroimaging; however, there is increasing interest in minimally invasive fluid biomarkers to detect TBI objectively across all ages. Preclinical porcine models offer controlled conditions to evaluate TBI with known biomechanical conditions and without co-morbidities. The objective of the current study was to establish pediatric porcine healthy reference ranges (RR) of common human serum TBI biomarkers and to report their acute time-course after non-impact rotational head injury. A retrospective analysis was completed to quantify biomarker concentrations in porcine serum samples collected from four-week-old female (n = 215) and uncastrated male (n = 6) Yorkshire piglets. Subjects were assigned to one of three experimental groups (sham, sagittal-single, sagittal-multiple) or to a baseline only group. A rapid non-impact rotational (RNR) head injury model was used to produce mild to moderate TBI in piglets following a single rotation and moderate to severe TBI following multiple rotations. The Quanterix Simoa Human Neurology 4-Plex A (N4PA) assay was used to quantify glial fibrillary acidic protein (GFAP), neurofilament light (Nf-L), tau, and ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1). The 95% healthy RR for females were calculated and validated for GFAP (6.3-69.4 pg/mL), Nf-L (9.5-67.2 pg/mL), and UCH-L1 (3.8-533.7 pg/mL). Rising early, GFAP increased significantly above the healthy RR for sagittal-single (to 164 and 243 pg/mL) and increased significantly higher in sagittal-multiple (to 494 and 413 pg/mL) groups at 30 min and 1 h post-injury, respectively, returning to healthy RR ranges by 1-week post-injury. Rising later, Nf-L increased significantly above the healthy RR by 1 day in sagittal-single (to 69 pg/mL) and sagittal-multiple groups (to 140 pg/mL) and rising further at 1 week (single = 231 pg/mL, multiple = 481 pg/mL). Sagittal-single and sagittal-multiple UCH-L1 serum samples did not differ from shams or the healthy RR. Sex differences were observed but inconsistent. Serum GFAP and Nf-L levels had distinct time-courses following head rotations in piglets, and both corresponded to load exposure. We conclude that serum GFAP and Nf-L offer promise for early TBI diagnosis and intervention decisions for TBI and other neurological trauma.

Virtual reality cricothyrotomy - a case-control study on gamification in emergency education

BACKGROUND

Cricothyrotomy is an invasive and rare emergency intervention to secure the airway in a "cannot intubate, cannot ventilate" situation. This leads to lack of routine. Cricothyrotomy is performed only hesitantly. Therefore, we aim to improve teaching by including a virtual reality (VR) cricothyrotomy as a learning tool.

METHODS

We programmed the VR cricothyrotomy in the C# programming language on the open-source Unity platform. We could include 149 students that we randomly assigned to either a study group (VR cricothyrotomy) or control group (educational video). We asked the study group to subjectively rate the VR cricothyrotomy. To evaluate our intervention (VR cricothyrotomy) we took the time participants needed to perform a cricothyrotomy on a plastic model of a trachea and evaluated the correct procedural steps.

RESULTS

The majority of students that performed the VR simulation agreed that they improved in speed (81%) and procedural steps (92%). All participants completed the cricothyrotomy in 47s ± 16s and reached a total score of 8.7 ± 0.7 of 9 possible points. We saw no significant difference in time needed to perform a cricothyrotomy between study and control group (p > 0.05). However, the total score of correct procedural steps was significantly higher in the study group than in the control group (p < 0.05).

CONCLUSIONS

Virtual reality is an innovative learning tool to improve teaching of emergency procedures. The VR cricothyrotomy subjectively and objectively improved correct procedural steps. Digitized education fills an educational gap between pure haptic experience and theoretical knowledge. This is of great value when focusing on extension of factual knowledge.

TRIAL REGISTRATION

DRKS00031736, registered on the 20th April 2023.

In-situ alignment of 3D printed anisotropic hard magnets

Within this work, we demonstrate in-situ alignment of the easy axis single-crystal magnetic particles inside a polymer matrix using fused filament fabrication. Two different magnetic materials are investigated: (i) Strontium hexaferrite inside a PA6 matrix, fill grade: 49 vol% and (ii) Samarium iron nitride inside a PA12 matrix, fill grade: 44 vol%. In the presence of the external alignment field, the strontium hexaferrite particles inside the PA6 matrix can be well aligned with a ratio of remnant magnetization to saturation magnetization in an easy axis of 0.7. No significant alignment for samarium iron nitride could be achieved. The results show the feasibility to fabricate magnets with arbitrary and locally defined easy axis using fused filament fabrication since the permanent magnets (or alternatively an electromagnet) can be mounted on a rotatable platform.

Pulmonary vein isolation with high power, short duration ablation leads to shorter procedure times associated with high success rates: a Prospective Randomized Trial

Funding Acknowledgements

Type of funding sources: None.

Background

The single procedure success rates of durable pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (AF) varies between 85 and 90 %.

This prospective, randomized study investigated the efficacy of high power, short duration ablation in a temperature-controlled mode versus standard power settings in terms of single-procedure arrhythmia-free outcome, safety and procedural time.

Methods and results

A total number of 176 patients undergoing de-novo catheter ablation for paroxysmal AF were randomized to two different treatment arms. In group-A patients, PVI was performed with RF-energy with standard power settings of 30 Watts in a temperature-controlled mode.

The ablation procedure in group B was performed with RF-energy with higher power settings of 45 Watts. In both groups the ablation was performed with ablation index (AI) and following the CLOSE protocol (Biosense Webster Thermocool STSF).

A total of 88 patients were randomized into each group without significant differences in baseline characteristics.

During a mean follow-up of 12 ± 4 months after a single procedure, 79 (90%) patients of group A were free of arrhythmia recurrence versus 82 (93 %) patients in group B (p=ns).

With regard to the procedural data, the procedure time was significantly shorter in group B (115.35 ± 15.38 versus 96.45 ± 17.19; p&lt;0.01), the flouroscopy time and dose area were also significantly lower in Group B (9.66 ± 3.86 vs 5.45 ± 2.35; 330.84 ± 150.36 vs 202.51 ± 135.23) and total ablation times were significantly shorter in group B ((Table 1). Both procedures were performed with a low number of complications, no pericardial effusion was seen in either group, in both groups two patients had a significant hematoma of the groin with the need of surgical repair.

Conclusions

RF-ablation with high power (45 Watts) in combination with ablation index and following the CLOSE protocol leads to shorter procedure times, a lower total ablation time and a good safety profile.

Predicted Global Spread of SARS-CoV-2 Alpha Variant of Concern via Air Travel

Purpose

To predict the global spread of SARS-CoV-2 Alpha Variant of Concern (VoC) from England via air travel and compare against observed importation.

Methods & Materials

Risk models were used to estimate a country's likelihood of importing at least one traveller infected with the Alpha VoC from England by January 19, 2021.

First, the prior 60-day incidence of Alpha VoC associated with each English airport was estimated using cumulative Alpha VoC cases reported by Public Health England between September 20, 2020 – January 4, 2021 proportionately allocated to each airport. Each airport's catchment population was derived from a probabilistic Huff model. Next, the prevalence of the Alpha VoC for each airport was derived from the estimated incidence to represent the probability that at least one departing traveller was infected with the Alpha VoC for each English airport. The prevalence and forecasted flight volumes were used to estimate the likelihood of each destination airport receiving at least one infected traveller from England. Forecasted flight volumes were based on historical passenger volumes data from the International Air Transport Association and prospective flight schedules from CIRIUM. All airport-level likelihoods were aggregated to the country-level.

Each country's predicted likelihood was compared against observed cases of Alpha VoC by January 25, 2021, collected by cov-lineages.org and a manual search of online sources.

Results

Among 211 countries, the median likelihood was 1.6% (interquartile range: 17.5%) and the mean was 13.9% (SD: 23.5%). In total, 28.9% (n=55) of countries had observed importation of the Alpha VoC by January 25^th. Fifteen of 16 countries with a predicted likelihood of importation greater than 50% had reported at least one case (kappa = 0.88), while 31 of 39 countries with a predicted likelihood lower than 1% did not detect a case (kappa = 0.92).

Conclusion

Risk models based on air travel to inform public health preparedness accurately identified most potential destinations at highest risk of importing the SARS-CoV-2 Alpha VoC.

Refined prediction and validation of individual risk using machine learning in transcatheter aortic valve implantation: TAVI Risk Machine (TRIM) scores

Background

Given the recent option for treatment using TAVI irrespective of surgical risk, general surgical risk scores have become less relevant, while TAVI-specific scores require refinement. Additionally, post-TAVI risk models are lacking; however, such risk models can support decision between post-TAVI treatment approaches, such as early discharge or close surveillance.

Purpose

This study aimed to predict 30-day mortality following transcatheter aortic valve implantation (TAVI) based on machine learning (ML) using data from the German Aortic Valve Registry.

Methods

Mortality risk was determined using a random forest ML model that was condensed in the newly developed TAVI Risk Machine (TRIM) scores, designed to represent clinically meaningful risk modelling before (TRIMpre) and after (TRIMpost) TAVI. Algorithm was trained and cross-validated on data of 24,452 patients and generalisation was examined on data of 5,889 patients.

Results

TRIMpost demonstrated significantly better performance than traditional scores (C-statistics value, 0.79; 95% confidence interval [CI] [0.74; 0.83]). An abridged TRIMpost score comprising 25 features (calculated using a web interface) exhibited significantly higher performance than traditional scores (C-statistics value, 0.74; 95% CI [0.70; 0.78]).

Conclusion

TRIM scores have high performance for risk estimation before and after TAVI. Together with clinical judgement, they may support standardised and objective decision-making before and after TAVI.

Funding Acknowledgement

Type of funding sources: None.

Pad, psychiatry and stigma

In 2018, the Swiss Academy of Medical Sciences (SAMW) published a new guideline on physician-assisted dying (PAD). In line with the SAMW guideline published in 2004, the patients’ ability to judge, their self-determination, careful consideration and permanence of their wish to die as well as the lack of therapeutic options were set as necessary conditions. However, while the previous wording considered assisted suicide to be ethically justifiable if the patient’s condition is terminal, the new guideline requires that it is unbearable. This difference has been the subject of intense discussion in Swiss healthcare professionals and the population alike. This controversy is particularly important for those affected by mental illness who have a persistent desire to die. This is because mental disorders cannot usually be classified as terminal illnesses, but they can certainly lead to suffering that is perceived as unbearable. Furthermore, it is known that persons with mental illness are subject to stigmatization. It is therefore likely that there is a connection between the stigmatization of mentally ill people and the position on PAD for this group. This talk provides theoretical background on this discusion and proposes a study protocol to investigate the acceptance of PAD in relation to the type of illness as well as the factors of unbearable suffering and terminality. It will furthermore look into the criteria of the 2004 and 2018 guidelines and will explore if there is a connection between stigmatization and the assessment of whether a person should be granted access to assisted suicide.

FAST: a randomised phase II study of zolbetuximab (IMAB362) plus EOX versus EOX alone for first-line treatment of advanced CLDN18.2-positive gastric and gastro-oesophageal adenocarcinoma

BACKGROUND

Claudin 18.2 (CLDN18.2) is contained within normal gastric mucosa epithelial tight junctions; upon malignant transformation, CLDN18.2 epitopes become exposed. Zolbetuximab, a chimeric monoclonal antibody, mediates specific killing of CLDN18.2-positive cells through immune effector mechanisms.

PATIENTS AND METHODS

The FAST study enrolled advanced gastric/gastro-oesophageal junction and oesophageal adenocarcinoma patients (aged ≥18 years) with moderate-to-strong CLDN18.2 expression in ≥40% tumour cells. Patients received first-line epirubicin + oxaliplatin + capecitabine (EOX, arm 1, n = 84) every 3 weeks (Q3W), or zolbetuximab + EOX (loading dose, 800 mg/m² then 600 mg/m² Q3W) (arm 2, n = 77). Arm 3 (exploratory) was added after enrolment initiation (zolbetuximab + EOX 1000 mg/m² Q3W, n = 85). The primary endpoint was progression-free survival (PFS) and overall survival (OS) was a secondary endpoint.

RESULTS

In the overall population, both PFS [hazard ratio (HR) = 0.44; 95% confidence interval (CI), 0.29-0.67; P < 0.0005] and OS (HR = 0.55; 95% CI, 0.39-0.77; P < 0.0005) were significantly improved with zolbetuximab + EOX (arm 2) compared with EOX alone (arm 1). This significant PFS benefit was retained in patients with moderate-to-strong CLDN18.2 expression in ≥70% of tumour cells (HR = 0.38; 95% CI, 0.23-0.62; P < 0.0005). Significant improvement in PFS was also reported in the overall population of arm 3 versus arm 1 (HR = 0.58; 95% CI, 0.39-0.85; P = 0.0114) but not in high CLDN18.2-expressing patients; no significant improvement in OS was observed in either population. Most adverse events (AEs) related to zolbetuximab + EOX (nausea, vomiting, neutropenia, anaemia) were grade 1-2. Grade ≥3 AEs showed no substantial increases overall (zolbetuximab + EOX versus EOX alone).

CONCLUSIONS

In advanced gastric/gastro-oesophageal junction and oesophageal adenocarcinoma patients expressing CLDN18.2, adding zolbetuximab to first-line EOX provided longer PFS and OS versus EOX alone. Zolbetuximab + EOX was generally tolerated and AEs were manageable. Zolbetuximab 800/600 mg/m² is being evaluated in phase III studies based on clinical benefit observed in the overall population and in patients with moderate-to-strong CLDN18.2 expression in ≥70% of tumour cells.

Age-related clinical and hemodynamic outcome following transcatheter aortic valve replacement: a swiss TAVI registry analysis

Background

Transcatheter aortic valve implantation (TA) is the preferred treatment modality for patients with severe aortic valve disease at high surgical risk and is expanding into lower risk populations. Therefore age range of treated patients is increasing.

Purpose

The aim of this study is to analyze age-related clinical and hemodynamic outcome of patients following TAVI in a nationwide, prospective, multicentre cohort (Swiss TAVI registry).

Methods

We retrospectively analyzed prospectively collected data from all patients included in the Swiss TAVI registry between February 2011 and December 2018. In an adjusted analysis, in-hospital, 30-days and 1-year outcome between four age groups were compared.

Results

Overall, 7097 patients underwent TAVI (&lt;70 years: n=324, 70–79 years: n=1913, 80–89 years: n=4353, 90–100 years n=507). Median STS risk score for mortality was 5.23±4.13% and differed significantly between age groups (3.46±4.10%, 3.97±3.73%, 5.57±3.97%, 8.22±4.74%; p=0.001). Valve predilatation was more often performed in older patients (54.3% vs. 54.3% vs. 60.7% vs. 69.6%; p≤0.001). Difference in hospital stay was statistically sigificant between age groups, numerically however not relevant (10.01±7.56 days vs. 9.25±6.38 days vs. 9.55±5.70 days vs 10.03±5.77 days; p=0.02). Post-procedural acute kidney injury stage 3 was highest in the youngest age group (3.4% vs. 1.6% vs. 1.1% vs. 1.0%; RR [95% CI] 0.65 (0.48–0.87); p=0,004) and rate of new pacemakers for conduction abnormalities increased significantly with age (10.2% vs. 13.7% vs. 17.1% vs. 18.7%; RR [95% CI] 1.22 (1.12–1.32); p&lt;0.001). There was no significant difference in life threatening/major bleeding (p=0.288/0.197) or major vascular complications (p=0.083).

All-cause mortality and cardiovascular mortality in hospital, at 30 days and at 1 year were highest in nonagenarians and higher in the patients &lt;70 years compared to patients of 70–79 years: in hospital all-cause mortality 2.2% vs. 1.6% vs. 2.9% vs. 5.5% (RR [95% CI] 1.64 (1.28–2.10), p&lt;0.001); 30 day all-cause mortality 3.1% vs. 2.0% vs. 3.7% vs. 6.7%; (HR [95% CI] 1.59 (1.30–1.96); p&lt;0.0001); 1-year all-cause mortality 10.9% vs. 10.4% vs. 12% vs. 19.5% (HR [95% CI] 1.27 (1.14–1.41); p&lt;0.001); in hospital cardiovascular mortality 1.5% vs. 1.5% vs. 2.6% vs. 5.1% (RR [95% CI] 1.70 (1.31–2.20), p&lt;0.001); 30 day cardiovascular mortality 2.2% vs. 1.9% vs. 3.3% vs. 6.3%; (HR [95% CI] 1.68 (1.35–2.09); p&lt;0.001); 1-year cardiovascular mortality 7.2% vs. 6.9% vs. 8.3% vs. 15.3% (HR [95% CI] 1.36 (1.19–1.55); p&lt;0.001). This held true, when hazard ratio was corrected for STS PROM score, femoral access vs other access and year of procedure.

Conclusion

In-hospital, 30-day and 1-year clinical outcome of nonagenarians undergoing TAVI are less favorable compared to lower age groups. Interestingly, clinical outcome of the patients group 70–79 years was the most favorable.

Mortality at 30 according to age

Funding Acknowledgement

Type of funding source: None

A multicentre, phase IIa study of zolbetuximab as a single agent in patients with recurrent or refractory advanced adenocarcinoma of the stomach or lower oesophagus: the MONO study

BACKGROUND

Claudin 18.2 (CLDN18.2) is physiologically confined to gastric mucosa tight junctions; however, upon malignant transformation, perturbations in cell polarity lead to CLDN18.2 epitopes being exposed on the cancer cell surface. The first-in-class monoclonal antibody, zolbetuximab (formerly known as IMAB362), binds to CLDN18.2 and can induce immune-mediated lysis of CLDN18.2-positive cells.

PATIENTS AND METHODS

Patients with advanced gastric, gastro-oesophageal junction (GEJ) or oesophageal adenocarcinomas with moderate-to-strong CLDN18.2 expression in ≥50% of tumour cells received zolbetuximab intravenously every 2 weeks for five planned infusions. At least three patients were enrolled in two sequential cohorts (cohort 1300 mg/m2; cohort 2600 mg/m2); additional patients were enrolled into a dose-expansion cohort (cohort 3600 mg/m2). The primary end point was the objective response rate [ORR: complete and partial response (PR)]; secondary end points included clinical benefit [ORR+stable disease (SD)], progression-free survival, safety/tolerability, and zolbetuximab pharmacokinetic profile.

RESULTS

From September 2010 to September 2012, 54 patients were enrolled (cohort 1, n = 4; cohort 2, n = 6; cohort 3, n = 44). Three patients in cohort 1 and 25 patients in cohorts 2/3 received at least 5 infusions. Antitumour activity data were available for 43 patients, of whom 4 achieved PR (ORR 9%) and 6 (14%) had SD for a clinical benefit rate of 23%. In a subgroup of patients with moderate-to-high CLDN18.2 expression in ≥70% of tumour cells, ORR was 14% (n = 4/29). Treatment-related adverse events occurred in 81.5% (n = 44/54) patients; nausea (61%), vomiting (50%), and fatigue (22%) were the most frequent.

CONCLUSIONS

Zolbetuximab monotherapy was well tolerated and exhibited antitumour activity in patients with CLDN18.2-positive advanced gastric or GEJ adenocarcinomas, with response rates similar to those reported for single-agent targeted agents in gastric/GEJ cancer trials.

CLINICALTRIALS.GOV NUMBER

NCT01197885.

The Danish STR sequence database: duplicate typing of 363 Danes with the ForenSeq™ DNA Signature Prep Kit

Some STR loci have internal sequence variations, which are not revealed by the standard STR typing methods used in forensic genetics (PCR and fragment length analysis by capillary electrophoresis (CE)). Typing of STRs with next-generation sequencing (NGS) uncovers the sequence variation in the repeat region and in the flanking regions. In this study, 363 Danish individuals were typed for 56 STRs (26 autosomal STRs, 24 Y-STRs, and 6 X-STRs) using the ForenSeq™ DNA Signature Prep Kit to establish a Danish STR sequence database. Increased allelic diversity was observed in 34 STRs by the PCR-NGS assay. The largest increases were found in DYS389II and D12S391, where the numbers of sequenced alleles were around four times larger than the numbers of alleles determined by repeat length alone. Thirteen SNPs and one InDel were identified in the flanking regions of 12 STRs. Furthermore, 36 single positions and five longer stretches in the STR flanking regions were found to have dubious genotyping quality. The combined match probability of the 26 autosomal STRs was 10,000 times larger using the PCR-NGS assay than by using PCR-CE. The typical paternity indices for trios and duos were 500 and 100 times larger, respectively, than those obtained with PCR-CE. The assay also amplified 94 SNPs selected for human identification. Eleven of these loci were not in Hardy-Weinberg equilibrium in the Danish population, most likely because the minimum threshold for allele calling (30 reads) in the ForenSeq™ Universal Analysis Software was too low and frequent allele dropouts were not detected.

Chondrodysplasia with multiple dislocations: comprehensive study of a series of 30 cases

The group of chondrodysplasia with multiple dislocations includes several entities, characterized by short stature, dislocation of large joints, hand and/or vertebral anomalies. Other features, such as epiphyseal or metaphyseal changes, cleft palate, intellectual disability are also often part of the phenotype. In addition, several conditions with overlapping features are related to this group and broaden the spectrum. The majority of these disorders have been linked to pathogenic variants in genes encoding proteins implicated in the synthesis or sulfation of proteoglycans (PG). In a series of 30 patients with multiple dislocations, we have performed exome sequencing and subsequent targeted analysis of 15 genes, implicated in chondrodysplasia with multiple dislocations, and related conditions. We have identified causative pathogenic variants in 60% of patients (18/30); when a clinical diagnosis was suspected, this was molecularly confirmed in 53% of cases. Forty percent of patients remain without molecular etiology. Pathogenic variants in genes implicated in PG synthesis are of major importance in chondrodysplasia with multiple dislocations and related conditions. The combination of hand features, growth failure severity, radiological aspects of long bones and of vertebrae allowed discrimination among the different conditions. We propose key diagnostic clues to the clinician.

Status of hormones and painkillers in wastewater effluents across several European states-considerations for the EU watch list concerning estradiols and diclofenac

Present technologies for wastewater treatment do not sufficiently address the increasing pollution situation of receiving water bodies, especially with the growing use of personal care products and pharmaceuticals (PPCP) in the private household and health sector. The relevance of addressing this problem of organic pollutants was taken into account by the Directive 2013/39/EU that introduced (i) the quality evaluation of aquatic compartments, (ii) the polluter pays principle, (iii) the need for innovative and affordable wastewater treatment technologies, and (iv) the identification of pollution causes including a list of principal compounds to be monitored. In addition, a watch list of 10 other substances was recently defined by Decision 2015/495 on March 20, 2015. This list contains, among several recalcitrant chemicals, the painkiller diclofenac and the hormones 17β-estradiol and 17α-ethinylestradiol. Although some modern approaches for their removal exist, such as advanced oxidation processes (AOPs), retrofitting most wastewater treatment plants with AOPs will not be acceptable as consistent investment at reasonable operational cost. Additionally, by-product and transformation product formation has to be considered. The same is true for membrane-based technologies (nanofiltration, reversed osmosis) despite of the incredible progress that has been made during recent years, because these systems lead to higher operation costs (mainly due to higher energy consumption) so that the majority of communities will not easily accept them. Advanced technologies in wastewater treatment like membrane bioreactors (MBR) that integrate biological degradation of organic matter with membrane filtration have proven a more complete elimination of emerging pollutants in a rather cost- and labor-intensive technology. Still, most of the presently applied methods are incapable of removing critical compounds completely. In this opinion paper, the state of the art of European WWTPs is reflected, and capacities of single methods are described. Furthermore, the need for analytical standards, risk assessment, and economic planning is stressed. The survey results in the conclusion that combinations of different conventional and advanced technologies including biological and plant-based strategies seem to be most promising to solve the burning problem of polluting our environment with hazardous emerging xenobiotics.

Influence of the substrate material on the knife-edge based profiling of tightly focused light beams

The performance of the knife-edge method as a beam profiling technique for tightly focused light beams depends on several parameters, such as the material and height of the knife-pad as well as the polarization and wavelength of the focused light beam under study. Here we demonstrate that the choice of the substrate the knife-pads are fabricated on has a crucial influence on the reconstructed beam projections as well. We employ an analytical model for the interaction of the knife-pad with the beam and report good agreement between our numerical and experimental results. Moreover, we simplify the analytical model and demonstrate, in which way the underlying physical effects lead to the apparent polarization dependent beam shifts and changes of the beamwidth for different substrate materials and heights of the knife-pad.

Bubble accumulation and its role in the evolution of magma reservoirs in the upper crust

Volcanic eruptions transfer huge amounts of gas to the atmosphere. In particular, the sulfur released during large silicic explosive eruptions can induce global cooling. A fundamental goal in volcanology, therefore, is to assess the potential for eruption of the large volumes of crystal-poor, silicic magma that are stored at shallow depths in the crust, and to obtain theoretical bounds for the amount of volatiles that can be released during these eruptions. It is puzzling that highly evolved, crystal-poor silicic magmas are more likely to generate volcanic rocks than plutonic rocks. This observation suggests that such magmas are more prone to erupting than are their crystal-rich counterparts. Moreover, well studied examples of largely crystal-poor eruptions (for example, Katmai, Taupo and Minoan) often exhibit a release of sulfur that is 10 to 20 times higher than the amount of sulfur estimated to be stored in the melt. Here we argue that these two observations rest on how the magmatic volatile phase (MVP) behaves as it rises buoyantly in zoned magma reservoirs. By investigating the fluid dynamics that controls the transport of the MVP in crystal-rich and crystal-poor magmas, we show how the interplay between capillary stresses and the viscosity contrast between the MVP and the host melt results in a counterintuitive dynamics, whereby the MVP tends to migrate efficiently in crystal-rich parts of a magma reservoir and accumulate in crystal-poor regions. The accumulation of low-density bubbles of MVP in crystal-poor magmas has implications for the eruptive potential of such magmas, and is the likely source of the excess sulfur released during explosive eruptions.

[Short-Term Cryotherapy--Putting Dynamic Foot and Ankle Stability at Risk?]

BACKGROUND

The application of ice or other forms of cooling represent a common method to treat acute musculoskeletal injuries during sporting events in order to reduce pain. Often athletes return to competition immediately after cooling. It is not known if short-term cryotherapy in the form of ice spray has an influence on the joint's dynamic stability. The aim of this study was to investigate if application of ice spray to the ankle has an effect on the dynamic stability of the joint in healthy participants.

METHODS

A randomized controlled single-blind pilot study with crossover-design was conducted. 22 healthy athletic participants (15 women, 7 men, mean age 31.8 years ± 5.7) were included. Time-to-stability (TTS) was used to investigate the effect of the interventions, ice spray and water spray, applied on the lateral ankle. TTS was assessed in medio-lateral (ML) and antero-posterior (AP) direction on a force plate with two different tests (side step down and 1-leg jump). Collected co-variables were age, gender, height, weight, previous ankle injuries, Tegner activity scale and leg dominance.

RESULTS

There were no significant differences between the two tests (side step down and 1-leg jump) in TTS after the application of ice spray or a water spray compared to the baseline (p > 0.05). There was no significant difference between the two interventions. The testing of the co-variable "previous ankle injury" showed a significant influence on the TTS in medio-lateral direction in the 1-leg jump test of the non-dominant leg after application of ice spray (p = 0.027). On the dominant leg same tendency could be found (p = 0.062).

CONCLUSION

The application of ice spray to the lateral ankle does not have an effect on dynamic stability in healthy participants. In participants with a previous ankle injury a significant decrease in dynamic stability after application of ice spray could be shown. Whether further factors affecting stability such as fatigue and the influence of an opponent player or the application of ice spray on adjacent muscles may augment this effect should be subject to future investigations.

Mafic magma replenishment, unrest and eruption in a caldera setting: insights from the 2006 eruption of Rabaul (Papua New Guinea)

Understanding the magmatic processes that drive unrest at silicic calderas remains a major goal in Volcanology. Rabaul in Papua New Guinea is an exceptional location because after two decades of unrest and a peak in seismicity and deformation in 1983–85, eruptive activity began in 1994 and is still ongoing. A particularly large sub-Plinian eruption occurred from Tavurvur in October 2006. Whole-rock compositions are andesitic and reflect mixing/mingling between basaltic and dacitic magmas from the same system. The magmas that fed the 2006 eruption were stored at about 930°C, with 1–3 wt% H2O, 25–520 ppm CO2, and 50–2500 ppm SO2 in the melt. Melt inclusions hosted in pyroxene, and plagioclase phenocrysts record fractional crystallization at ≤200 MPa under relatively dry and poorly oxidizing conditions. Magma mixing/mingling is expressed as heterogeneous glass compositions, strongly zoned phenocrysts, and mafic crystal aggregates. A textural maturation from fine, acicular to large, blocky crystal clots implies different relative ages of formation. Modelling the chemical zoning of plagioclase shows that mafic–silicic interactions started a couple of decades prior to the 2006 eruption and continued until days to weeks prior to eruption. Basaltic replenishments have been driving unrest and eruption at the Rabaul caldera since the 1970s.

Supplementary material:

Tables and figures reporting the composition of the Tavurvur 2006, Kombiu and 1.4 ka BP caldera samples and showing thermodynamic modelling with MELTS are available at http://www.geolsoc.org.uk/SUP18816

Myopic astigmatism as a substitute for accommodation in pseudophakia

Pseudophacic eyes can be made nearly spectacle-independent by increasing the depth of focus of the uncorrected implanted eye. When the postoperative ametropia is a simple myopic astigmatism the uncorrected visual acuity can be above 0.4 from far to near. The quasi-constant visual acuity in different distances is due to the slow change in the dimension of the blurred retinal image when a point source comes nearer to a myopic astigmatic eye. The intersection of Sturm's conoid and the retina (i.e. the blur spot) changes mainly in form but its size changes much less than in a sperical ametropia. To obtain such a refraction the dioptric change in corneal power induced by surgery must be included in the calculation of the intraocular lens. The induced corneal ametropia is a mixed astigmatism with no equivalent power. The optical principles and the clinical results obtained with iridocapsular Binkhorst lenses are discussed.

Three ophthalmological instruments: the rotating contact glass holder, the cutying forceps and the diamond cystotome

Three new ophthalmological instruments are described: a rotating contact glass holder for easier control of the three-mirror Goldmann or other diagnostic contact lens which must be rotated on the eye; a suture-tying forceps combined with a sapphire blade, combining the tying and cutting functions in one instrument and a diamond cystotome for anterior capsulectomy with a cutting edge of unequalled sharpness.

In human basophils, IL-3 selectively induces RANKL expression that is modulated by IgER-dependent and IgER-independent stimuli

BACKGROUND

Receptor activator of NF-κB ligand (RANKL) is expressed as either surface (hRANKL1, hRANKL2) or soluble (hRANKL3) form. RANKL is involved in multifaceted processes of immunoregulation and bone resorption such as they occur in rheumatoid arthritis (RA). Interestingly, activated basophils, which are effector cells in allergic inflammation, contribute to the progress of collagen-induced arthritis (CIA), a mouse model for RA. Here, we investigate under which conditions human basophils express RANKL.

METHODS

Among other stimuli, basophils were cultured with IL-3 alone. Alternatively, as a secondary stimulus, IgER-dependent or IgER-independent agents were added simultaneously either with IL-3 or after prolonged IL-3 culturing. Expression of RANKL protein and mRNA was analyzed by flow cytometry, ELISA, and real-time PCR. A coculture system was applied to investigate biological activity of basophil-derived RANKL.

RESULTS

We show that in human basophils, IL-3 but no other stimulus induces de novo expression of soluble and surface RANKL, of which the latter enhances survival of MoDC. Upon simultaneous stimulation, IgER cross-linking reduces surface RANKL expression, while IgER-independent stimuli have no effect. This is in contrast to consecutive stimulation, as triggering with both IgER-dependent and IgER-independent stimuli enhances RANKL expression, particularly in its soluble form. Real-time PCR analysis shows that RANKL expression is mainly regulated at the mRNA level.

CONCLUSION

This study identifies IL-3 as a potent inducer of RANKL expression in human basophils, suggesting them to interact with bone physiology and activation of immune cells. IgER-dependent and IgER-independent stimuli modulate the IL-3-mediated RANKL expression in a time- and stimulus-dependent fashion.

Corrections to the knife-edge based reconstruction scheme of tightly focused light beams

The knife-edge method is an established technique for profiling light beams. It was shown, that this technique even works for tightly focused beams, if the material and geometry of the probing knife-edges are chosen carefully. Furthermore, it was also reported recently that this method fails, when the knife-edges are made from pure materials. The artifacts introduced in the reconstructed beam shape and position depend strongly on the edge and input beam parameters, because the knife-edge is excited by the incoming beam. Here we show, that the actual beam shape and spot size of tightly focused beams can still be derived from knife-edge measurements for pure edge materials and different edge thicknesses by adapting the analysis method of the experimental data taking into account the interaction of the beam with the edge.