Probing the Degree of Coherence through the Full 1D to 3D Crossover.

We experimentally study a gas of quantum degenerate ^{87}Rb atoms throughout the full dimensional crossover, from a one-dimensional (1D) system exhibiting phase fluctuations consistent with 1D theory to a three-dimensional (3D) phase-coherent system, thereby smoothly interpolating between these distinct, well-understood regimes. Using a hybrid trapping architecture combining an atom chip with a printed circuit board, we continuously adjust the system's dimensionality over a wide range while measuring the phase fluctuations through the power spectrum of density ripples in time-of-flight expansion. Our measurements confirm that the chemical potential µ controls the departure of the system from 3D and that the fluctuations are dependent on both µ and the temperature T. Through a rigorous study we quantitatively observe how inside the crossover the dependence on T gradually disappears as the system becomes 3D. Throughout the entire crossover the fluctuations are shown to be determined by the relative occupation of 1D axial collective excitations.

Kirkwood-Buff integrals: From fluctuations in finite volumes to the thermodynamic limit.

The Kirkwood-Buff theory is a cornerstone of the statistical mechanics of liquids and solutions. It relates volume integrals over the radial distribution function, so-called Kirkwood-Buff integrals (KBIs), to particle number fluctuations and thereby to various macroscopic thermodynamic quantities such as the isothermal compressibility and partial molar volumes. Recently, the field has seen a strong revival with breakthroughs in the numerical computation of KBIs and applications to complex systems such as bio-molecules. One of the main emergent results is the possibility to use the finite volume KBIs as a tool to access finite volume thermodynamic quantities. The purpose of this Perspective is to shed new light on the latest developments and discuss future avenues.

[Radiological evaluation of acute abdomen in children]. / Radiologische Abklärung des akuten Abdomens im Kindesalter.

CLINICAL/METHODICAL ISSUE: Acute, non-traumatic abdominal pain is one of the main reasons for medical consultation in pediatric patients. Knowledge of different diseases and their age dependence is essential for correct diagnosis and treatment. STANDARD RADIOLOGICAL METHODS: Ultrasonography is the imaging method of choice. X­ray is only used in case of emergency, e. g., suspected perforation. METHODICAL INNOVATIONS: Contrast-enhanced ultrasonography (CEUS) and elastography complement ultrasonography. PERFORMANCE: Magnetic resonance imaging is of increasing relevance for differential diagnosis of unclear sonographic results. PRACTICAL RECOMMENDATIONS: The primary imaging modality in pediatric patients is ultrasonography. Cross-sectional imaging should only be used in cases of unclear sonographic findings.

3D-printed components for quantum devices.

Recent advances in the preparation, control and measurement of atomic gases have led to new insights into the quantum world and unprecedented metrological sensitivities, e.g. in measuring gravitational forces and magnetic fields. The full potential of applying such capabilities to areas as diverse as biomedical imaging, non-invasive underground mapping, and GPS-free navigation can only be realised with the scalable production of efficient, robust and portable devices. We introduce additive manufacturing as a production technique of quantum device components with unrivalled design freedom and rapid prototyping. This provides a step change in efficiency, compactness and facilitates systems integration. As a demonstrator we present an ultrahigh vacuum compatible ultracold atom source dissipating less than ten milliwatts of electrical power during field generation to produce large samples of cold rubidium gases. This disruptive technology opens the door to drastically improved integrated structures, which will further reduce size and assembly complexity in scalable series manufacture of bespoke portable quantum devices.

MasterOnline Periodontology and Implant Therapy-revisited after seven years: A case study of the structures and outcomes in a blended learning CPD.

INTRODUCTION: There is a great need for postgraduate training and continuing professional development (CPD), specifically in the field of periodontology. Despite the plenty of periodontal CPDs, there is a lack of information about the performance of CPDs in a blended learning setting. This study is a case study of the structures and outcomes in a blended learning CPD programme in periodontology, the MasterOnline Periodontology and Implant Therapy hosted by the University of Freiburg's Dental School. MATERIAL AND METHODS: The structures of the blended learning CPD were analysed with the aims to (i) make explicit how various innovative educational methods and ICT tools can be successfully applied to a Web-supported postgraduate periodontology training programme, (ii) identify the programme's impact on learning transfer in students' dental practices and (iii) identify other outcomes, synergies and any changes required during the existence. Using qualitative interviewing, the various types of learning transfer and elements of the study programme that foster transfer could be exemplified. RESULTS: A period of 7 years was analysed. In this duration, 50 students successfully graduated to a master of science. Qualitative interviews were performed with six students and four teachers affirming the learning transfer in a blended learning setting. CONCLUSIONS: This case study shows that blended learning can be a successful approach for CPD in dentistry.

Processes of care in surgical patients who died with hospital-acquired infections in Australian hospitals.

BACKGROUND: Infection may complicate surgical patients' hospital admission. The effect of hospital-acquired infections (HAIs) on processes of care among surgical patients who died is unknown. AIM: To investigate the effect of HAIs on processes of care in surgical patients who died in hospital. METHODS: Surgeon-recorded infection data extracted from a national Australian surgical mortality audit (2012-2016) were grouped into HAIs and no infection. The audit included all-age surgical patients, who died in hospital. Not all patients had surgery. Excluded from analysis were patients with community-acquired infection and those with missing timing of infection. Multivariate logistic regression was used to determine the adjusted effects of HAIs on the processes of care in these patients. Costs associated with HAIs were estimated. FINDINGS: One-fifth of surgical patients who died did so with an HAI (2242 out of 11,681; 19.2%). HAI patients had increased processes of care compared to those who died without infection: postoperative complications [51.0% vs 30.3%; adjusted odds ratio (aOR): 2.20; 95% confidence interval (CI): 1.98-2.45; P < 0.001]; unplanned reoperations (22.6% vs 10.9%; aOR: 2.38; 95% CI: 2.09-2.71; P < 0.001) and unplanned intensive care unit admission (29.3% vs 14.8%; aOR: 2.18; 95% CI: 1.94-2.45; P < 0.001). HAI patients had longer hospital admissions and greater hospital costs than those without infection. CONCLUSION: HAIs were associated with increased processes of care and costs in surgical patients who died; these outcomes need to be investigated in surgical patients who survive.

There is more to accommodation of the eye than simply minimizing retinal blur.

Eyes of children and young adults change their optical power to focus nearby objects at the retina. But does accommodation function by trial and error to minimize blur and maximize contrast as is generally accepted? Three experiments in monocular and monochromatic vision were performed under two conditions while aberrations were being corrected. In the first condition, feedback was available to the eye from both optical vergence and optical blur. In the second, feedback was only available from target blur. Accommodation was less precise for the second condition, suggesting that it is more than a trial-and-error function. Optical vergence itself seems to be an important cue for accommodation.

Superfluid flow above the critical velocity.

Superfluidity and superconductivity have been widely studied since the last century in many different contexts ranging from nuclear matter to atomic quantum gases. The rigidity of these systems with respect to external perturbations results in frictionless motion for superfluids and resistance-free electric current flow in superconductors. This peculiar behaviour is lost when external perturbations overcome a critical threshold, i.e. above a critical magnetic field or a critical current for superconductors. In superfluids, such as liquid helium or ultracold gases, the corresponding quantities are a critical rotation rate and a critical velocity respectively. Enhancing the critical values is of great fundamental and practical value. Here we demonstrate that superfluidity can be completely restored for specific, arbitrarily large flow velocities above the critical velocity through quantum interference-induced resonances providing a nonlinear counterpart of the Ramsauer-Townsend effect occurring in ordinary quantum mechanics. We illustrate the robustness of this phenomenon through a thorough analysis in one dimension and prove its generality by showing the persistence of the effect in non-trivial 2d systems. This has far reaching consequences for the fundamental understanding of superfluidity and superconductivity and opens up new application possibilities in quantum metrology, e.g. in rotation sensing.

An oral health optimized diet can reduce gingival and periodontal inflammation in humans - a randomized controlled pilot study.

BACKGROUND: The aim of this pilot study was to investigate the effects of four weeks of an oral health optimized diet on periodontal clinical parameters in a randomized controlled trial. METHODS: The experimental group (n = 10) had to change to a diet low in carbohydrates, rich in Omega-3 fatty acids, and rich in vitamins C and D, antioxidants and fiber for four weeks. Participants of the control group (n = 5) did not change their dietary behavior. Plaque index, gingival bleeding, probing depths, and bleeding upon probing were assessed by a dentist with a pressure-sensitive periodontal probe. Measurements were performed after one and two weeks without a dietary change (baseline), followed by a two week transitional period, and finally performed weekly for four weeks. RESULTS: Despite constant plaque values in both groups, all inflammatory parameters decreased in the experimental group to approximately half that of the baseline values (GI: 1.10 ± 0.51 to 0.54 ± 0.30; BOP: 53.57 to 24.17 %; PISA: 638 mm(2) to 284 mm(2)). This reduction was significantly different compared to that of the control group. CONCLUSION: A diet low in carbohydrates, rich in Omega-3 fatty acids, rich in vitamins C and D, and rich in fibers can significantly reduce gingival and periodontal inflammation. TRIAL REGISTRATION: German Clinical Trials Register; https://www.germanctr.de (DRKS00006301). Registered on 2015-02-21.

Acute kidney injury following liver transplantation: a systematic review of published predictive models.

Acute kidney injury is a frequent postoperative complication amongst liver transplant recipients and is associated with increased morbidity and mortality. This systematic review analysed the existing predictive models, in order to solidify current understanding. Articles were selected for inclusion if they described the primary development of a clinical prediction model (either an algorithm or risk score) to predict AKI post liver transplantation. The database search yielded a total of seven studies describing the primary development of a prediction model or risk score for the development of AKI following liver transplantation. The models span thirteen years of clinical research and highlight a gradual change in the definitions of AKI, emphasising the need to employ standardised definitions for subsequent studies. Collectively, the models identify a diverse range of predictive factors with several common trends. They emphasise the impact of preoperative renal dysfunction, liver disease severity and aetiology, metabolic risk factors as well as intraoperative variables including measures of haemodynamic instability and graft quality. Although several of the models address postoperative parameters, their utility in predictive modelling seems to be of questionable relevance. The common risk factors identified within this systematic review provide a minimum list of variables, which future studies should address. Research in this area would benefit from prospective, multi-site studies with larger cohorts as well as the subsequent internal and external validation of predictive models. Ultimately, the ability to identify patients at high risk of post-transplant AKI may enable early intervention and perhaps prevention.

Electron-Phonon Coupling in the Bulk of Anatase TiO2 Measured by Resonant Inelastic X-Ray Spectroscopy.

We investigate the polaronic ground state of anatase TiO2 by bulk-sensitive resonant inelastic x-ray spectroscopy (RIXS) at the Ti L3 edge. We find that the formation of the polaron cloud involves a single 95 meV phonon along the c axis, in addition to the 108 meV ab-plane mode previously identified by photoemission. The coupling strength to both modes is the same within error bars, and it is unaffected by the carrier density. These data establish RIXS as a directional bulk-sensitive probe of electron-phonon coupling in solids.

Statin therapy in critically-ill patients with severe sepsis: a review and meta-analysis of randomized clinical trials.

UNLABELLED: While statins are indicated to reduce blood cholesterol levels, they also have anti-inflammatory and immunomodulatory effects. Several observational cohort studies suggested that statins may improve survival and reduce complications in patients with sepsis. Recent randomized controlled studies in critically ill patients have been conducted and published. In this paper we present a meta-analysis of these randomized trials. METHODS: An electronic article search through PubMed was performed. Only randomized controlled trials including critically ill adult patients with severe sepsis were retained. A meta-analysis was performed as detailed in text below. Overall analysis including 1818 patients total from 4 studies showed that there was no difference in 60-day mortality between statins (223/903) and placebo (233/899) [risk ratio, 0.930; 95% CI, 0.722 to 1.198]. Similarly, no difference in 28-day mortality was observed between groups (statins 191/907, placebo 199/911; risk ratio 0.953; 95% CI, 0.715 to 1.271). The results of this meta-analysis confirm that the use of statin therapy should not be recommended in the management of severe sepsis in critically ill patients. Statins should be continued with caution and only if necessary, as one study reported that the statin group had a higher rate of hepatic and renal failure.

Climate change is catchy--but when will it really hurt?

Concern and general awareness about the impacts of climate change in all sectors of the social-ecological-economic system is growing as a result of improved climate science products and information, as well as increased media coverage of the apparent manifestations of the phenomenon in our society. However, scales of climate variability and change, in space and time, are often confused and so attribution of impacts on various sectors, including the health sector, can be misunderstood and misrepresented. In this review, we assess the mechanistic links between climate and infectious diseases in particular, and consider how this relationship varies, and may vary according to different time scales, especially for aetiologically climate-linked diseases. While climate varies in the medium (inter-annual) time frame, this variability itself may be oscillating and/or trending on cyclical and long-term (climate change) scales because of regional and global scale climate phenomena such as the El-Nino southern oscillation coupled with global-warming drivers of climate change. As several studies have shown, quantifying and modelling these linkages and associations at appropriate time and space scales is both necessary and increasingly feasible with improved climate science products and better epidemiological data. The application of this approach is considered for South Africa, and the need for a more concerted effort in this regard is supported.