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Reporting of flow diagrams in randomised controlled trials published in periodontology and implantology: a survey
No full textBackground: Item 13 of the CONSORT guidelines recommends documentation of the participant flow in randomised clinical trials (RCTs) using a diagram. In the medical literature, the reporting of the flow of participants in RCTs has been assessed to be inadequate. The quality of reporting flow diagrams in periodontology and implantology remains unknown. The aim of this study was to assess the reporting of flow diagrams in RCTs published in periodontology and implantology journals. Materials and Methods:
RCTs published between 15th January 2018 and 15th January 2022 in twelve high-ranked periodontology and implantology journals were identified. Trial characteristics at the RCT level were extracted. The flow diagram included in each RCT was assessed for completeness of reporting in relation to published criteria and the CONSORT flow diagram template. Results: From the 544 eligible articles, 85% were single-centre, 82% of parallel-group design and 79% investigated surgical interventions. Three-hundred and fifteen (58%) articles were published in CONSORT endorsing journals. A flow diagram was reported in 317 (58%) trials and reporting was more common in periodontology (73.1%). Overall, 56% of publications with a flow diagram reported a complete CONSORT flow diagram, while in 44% of flow diagrams, at least one point from the CONSORT reporting template was missing. Reasons for loss to follow-up (69.7%) and exclusions from the RCT analysis (86.4%) were poorly reported. Conclusion: The reporting of flow diagrams in periodontology and implantology RCTs was sub-optimal. Greater awareness of the importance of fully completing the participant CONSORT flow diagram is required
Short-term-outcomes of idiopathic epiretinal membranes treated with pars-planavitrectomy – examination of visual function and OCT-morphology
No full textBackground: Epiretinal membranes (ERM) represent one of the most common findings in retinal examination. Structural changes of the retinal layers in patients with ERM can be visualized and classified using OCT. The purpose of this study is to evaluate structural and functional changes related to surgical treatment of ERM. Methods: Monocentric retrospective analysis of 92 patients who underwent 23-gauge-pars plana vitrectomy (ppV) combined with cataract surgery for idiopathic ERM from 2015 to 2020. Visual acuity was determined directly preoperatively, at four weeks and three months postoperatively. Disease stage and tomographic biomarkers related to ERM were assessed in OCT imaging. Results: 92 eyes of 92 patients were included. At the time of surgery, the mean patient age was 71 years. Visual acuity improved significantly by 2 lines postoperatively, on average from LogMar 0.4 to 0.2 (p < 0.001). Disease stage regressed from stage 3 to stage 2 postoperatively (p < 0.001). No patient had stage 4 postoperatively (n = 0). In the presence of preoperative intraretinal fluid, mean retinal thickness was 488 μm and decreased to 392 μm postoperatively (n = 32; p < 0.001). Preoperative presence of a Cotton Ball Sign (n = 30) was associated with better visual acuity (p = 0.009). This was also visible in patients with preoperative vitreomacular traction syndrome (p < 0.001). The presence of preoperative intraretinal fluid showed a tendency towards better disease staging after surgery (p = 0.080). Conclusion: Surgery was able to achieve visual improvement and morphological regression of the preoperative OCT findings related to ERM. ppV led to a reduction in retinal thickness and disease stage. The presence of the Cotton Ball Sign and vitreomacular traction was associated with better visual acuity in the follow-up period. In our cohort the preoperative presence of intraretinal fluid showed a tendency for better postoperative disease staging
Tamm–Horsfall protein in humane urine: sex-dependent differences in the excretion and N-glycosylation pattern
No full textTamm–Horsfall protein (THP) is a highly N-glycosylated protein from epithelial cells of the ascending limb of Henle loop. It is secreted into the urine as part of the innate immune response against uropathogenic pathogens. As women are more likely to suffer from urinary tract infections, biomedical studies were conducted to investigate sex-differences in THP excretion, as well as differences in the THP N-glycosylation pattern. A total of 238 volunteers (92 men, 146 women, 69 with hormonal contraceptives) participated in this study, providing urine samples. Women showed a clear tendency to have higher THP concentration and excretion rates than men (p < 0.16). Regular intake of hormonal contraceptives had no significant influence on urinary THP concentration compared to no regular intake. The individual N-glycosylation pattern of THP in urine samples from randomly selected individuals (10 female, 10 male) was investigated after enzymatic release and MS analysis of the oligosaccharides. Female subjects tended to have an increased proportion of oligomannose type N-glycans and non-fucosylated glycans, whereas men had an increased proportion of fucosylated complex-type glycans. The higher level of oligomannose-type glycans in THP from women might be explained by a self-defence mechanism to overcome the higher infections pressure by the female anatomical properties
Die Fortschritte des Community Cloud Computing in dem Business-to-Business-Kaufprozess
No full textIn times of digitalization, new ways occur to integrate suppliers in the B2B buying process. Community cloud computing enhances the collaboration between B2B buyers and suppliers. However, so far, there is little empirical evidence on how B2B buyers can use community cloud computing to integrate suppliers in the B2B buying process. This study investigates the areas of application, motives, and risks of B2B buyers to use community cloud computing for supplier integration. We use an exploratory research design and conducted semi-structured interviews with 14 experts in the German market. Even though our results show that community cloud computing is not an established technology, we find that B2B buyers use cloudbased procurement systems to enhance supplier integration. Interestingly, cloud-based procurement systems appear in all steps of the B2B buying process. This study identifies four ideal types of B2B buying processes, whose manifestations depend on the buying situation and the importance of the product. The use of cloud-based procurement systems in B2B buying adds up to the three main outcomes cost reduction, time savings, and resource access. We provide recommendations to B2B buyers and suppliers facing the four types how to use cloud computing in order to establish long-term relationships. Finally, we open up new research
areas to further explore this topic.In Zeiten der Digitalisierung ergeben sich neue Wege, Lieferanten in den B2B-Einkaufsprozess zu integrieren. Community Cloud Computing verbessert die Zusammenarbeit zwischen B2B-Einkäufern und -Lieferanten. Bislang gibt es jedoch kaum empirische Erkenntnisse darüber, wie B2B-Käufer Community Cloud Computing nutzen können, um Lieferanten in den B2B-Kaufprozess zu integrieren. Diese Studie untersucht die Anwendungsbereiche, Motive und Risiken von B2B-Käufern, Community Cloud Computing für die Lieferantenintegration zu nutzen. Wir wenden ein exploratives Forschungsdesign an und führen semi-strukturierte Interviews mit 14 Experten auf dem deutschen Markt durch. Obwohl unsere Ergebnisse zeigen, dass Community Cloud Computing keine etablierte Technologie ist, stellen wir fest, dass B2B-Käufer cloudbasierte Beschaffungssysteme nutzen, um die Lieferantenintegration zu verbessern. Interessanterweise tauchen Cloud-basierte Beschaffungssysteme in allen Schritten des B2B-Einkaufsprozesses auf. Diese Studie identifiziert vier ideale Arten von B2B-Einkaufsprozessen, deren Erscheinungsformen von der Einkaufssituation und der Bedeutung des Produkts abhängen. Der Einsatz Cloud-basierter Beschaffungssysteme beim B2B-Einkauf addiert sich zu den drei Hauptergebnissen Kostensenkung, Zeitersparnis und Ressourcenzugang. Wir geben B2B-Einkäufern und -Lieferanten, die mit den vier Arten von Cloud Computing konfrontiert sind, Empfehlungen, wie sie Cloud Computing nutzen können, um langfristige Beziehungen aufzubauen. Schließlich eröffnen wir neue Forschungsbereiche, um dieses Thema weiter zu erforschen
The Influence of Polyethylene Oxide Degradation in Polymer-Based Electrolytes for NMC and Lithium Metal Batteries
No full textA multilayered ternary solid polymer electrolyte (TSPE) is presented. First, the influence of polyethylene oxide degradation on cell failure, development of subsequent volatile degradation products, and cell impedance is analyzed. The low electrochemical stability window/oxidative stability (≥3.8 V) results in side-chain oxidation and loss of active material. Subsequently, electrolyte stability is improved and a thin-film (≤50 μm) TSPE with three functional layers is developed to match the wide-ranging electrolyte requirements toward Li metal anodes and different cathode materials like LiNi0.6Mn0.2Co0.2O2 and LiFePO4 (NCM622, LFP). The high-voltage stability of ≥4.75 V makes the TSPE a promising candidate in high-voltage applications. Because of high Coulombic efficiencies in NMC622‖Li metal (99.7%) and LFP‖Li metal (99.9%) cells, the presented electrolyte enables stable long-term cycling with great capacity retention of 86% and 94%, respectively. The temperature stability of >300 °C and the capability to prevent high surface area Li and dendrite formation (even at an areal capacity utilization of >40 mAh cm−2) contribute to high safety under a wide range of conditions
The soft X-ray and XUV split-and-delay unit at beamlines FL23/24 at FLASH2
No full textA split-and-delay unit for the extreme ultraviolet and soft X-ray spectral regions has been built which enables time-resolved experiments at beamlines FL23 and FL24 at the Free-electron LASer in Hamburg (FLASH). Geometric wavefront splitting at a sharp edge of a beam splitting mirror is applied to split the incoming soft X-ray pulse into two beams. Ni and Pt coatings at grazing incidence angles have been chosen in order to cover the whole spectral range of FLASH2 and beyond, up to hν = 1800 eV. In the variable beam path with a grazing incidence angle of ϑd = 1.8°, the total transmission (T) ranges are of the order of 0.48 0.50 for 100 eV 0.06 for hν 0.61 with the Ni coating and T > 0.23 with a Pt coating is achieved. Soft X-ray pump/soft X-ray probe experiments are possible within a delay range of −5 ps < Δt < +18 ps with a nominal time resolution of tr = 66 as and a measured timing jitter of tj = 121 ± 2 as. First experiments with the split-and-delay unit determined the averaged coherence time of FLASH2 to be τc = 1.75 fs at λ = 8 nm, measured at a purposely reduced coherence of the free-electron laser
A triple distinction of cerebellar function for oculomotor learning and fatigue compensation
No full textThe cerebellum implements error-based motor learning via synaptic gain adaptation of an inverse model, i.e. the mapping of a spatial movement goal onto a motor command. Recently, we modeled the motor and perceptual changes during learning of saccadic eye movements, showing that learning is actually a threefold process. Besides motor recalibration of (1) the inverse model, learning also comprises perceptual recalibration of (2) the visuospatial target map and (3) of a forward dynamics model that estimates the saccade size from corollary discharge. Yet, the site of perceptual recalibration remains unclear. Here we dissociate cerebellar contributions to the three stages of learning by modeling the learning data of eight cerebellar patients and eight healthy controls. Results showed that cerebellar pathology restrains short-term recalibration of the inverse model while the forward dynamics model is well informed about the reduced saccade change. Adaptation of the visuospatial target map trended in learning direction only in control subjects, yet without reaching significance. Moreover, some patients showed a tendency for uncompensated oculomotor fatigue caused by insufficient upregulation of saccade duration. According to our model, this could induce long-term perceptual compensation, consistent with the overestimation of target eccentricity found in the patients’ baseline data. We conclude that the cerebellum mediates short-term adaptation of the inverse model, especially by control of saccade duration, while the forward dynamics model was not affected by cerebellar pathology
Can the Dose Constraints Be Trusted? Actual Dose Exposure of Bladder and Rectum During Prostate Cancer Radiotherapy
No full textBackground/Objectives: The actual daily dose distribution during image-guided radiotherapy (IGRT) for prostate cancer (PCa) deviates from the planned due to positional and volumetric changes in the patient’s body and organs at risk (OAR). This study investigates the difference between planned and delivered dose, by calculating the actual daily dose to bladder and rectum for each radiotherapy fraction. The impact of OAR volumes on dose distribution and the correlation with treatment-related toxicities will be evaluated. Methods: A cone-beam computed tomography (CBCT) based daily dose calculation was performed for a total of 821 CBCT scans of 20 patients with localized PCa treated with IGRT. Each fraction’s dose-volume histogram was analyzed, and toxicities were correlated with OAR dose exposures. Results: Daily dosimetric evaluation showed a significant increase in bladder V65–V70 and rectum V50–V70 compared to planned values (p ≤ 0.003 each). In contrast to bladder Dmean, the rectum Dmean was significantly increased (0.47 vs. 0.55; p < 0.001). For the bladder an exponential dose-volume relationship was demonstrated, while no dose-volume relationship was found for the rectum. On average, patients with increased genitourinary toxicities received significantly increased bladder Dmean (0.44 vs. 0.63, p = 0.014). Conclusions: Conventional dose evaluation via a summation plan rather underestimates daily dosimetric parameters. For adaptive radiotherapy of PCa, volumetric parameters rather than mean doses should be used for daily treatment planning constraints. Because established dose constraints cannot be reduced to a single fraction, reasonable dose constraints should consider daily positional and volumetric changes, rather than relying on a single planning CT
Diagnostic criteria to differentiate pathological procrastinators from common delayers: a re-analysis
No full textDetection and treatment of clinically relevant forms of procrastination would be greatly facilitated by diagnostic criteria as formulated for psychological disorders in the Diagnostic and Statistical Manual (DSM-5). In the present article, the steps for deriving and validating diagnostic criteria for pathological procrastination are described. In an online survey of a random sample of N = 10,000 German university students, 990 answered 13 items derived from the attempts in the literature to define procrastination, the Aitken Procrastination Inventory (API) and the Patient Health Questionnaire (PHQ-9). A subset of six items related to the first factor 'onset delay' of the API was selected by Best Subset Multiple Regression (BSMR). A latent class analysis (LCA) of these six items sorted the students into six clusters. A cluster of 'pathological procrastinators' (10%) was separated from the clusters of less impaired 'habitual, average, and occasional delayers'. In addition, a cluster of 'unconcerned delayers' (10%), with strong procrastination tendencies but little personal disadvantages, and a small cluster of 'fast performers' (2%) emerged. The 'pathological procrastinators' differed from all other clusters significantly on nine of the 13 items. They were older, had studied longer but had fulfilled less of their study obligations and were more depressed. The answer options of the six questions were collapsed into two categories '(procrastination feature present for at least half a year or absent)'. These criteria were used for the clinical diagnosis of pathological procrastination. For a diagnosis, two fixed criteria '(delaying important tasks needlessly and strong interference with personal goals)' plus at least two of four additional criteria '(time spent procrastinating, time pressure, physical and psychological complaints, below performance potential)' must be met. This diagnostic rule captured 92% from the cluster of 'pathological procrastinators' and 10% of the 'habitual delayers', but no one from the remaining clusters. Using these diagnostic criteria for clinical diagnosis and intervention decisions will facilitate the comparison and integration of the results from future studies of procrastination
Digitale Kompetenzen schaffen
No full textDurch die Corona-Pandemie ist deutlich geworden, wie notwendig die gezielte Vermittlung digitaler Kompetenz in allen Lebensbereichen ist. Vor allem Schulen stehen jetzt vor den Fragen: Welche Facetten digitaler Kompetenz sollen vermittelt werden? Und wie verändert sich das Verständnis von gutem Unterricht