72 research outputs found
Cryogenic orthogonal turning of Ti-6Al-4V – Analysis of nitrogen supply pressure variation and subcooler usage
Cooling of machining operations by liquid nitrogen is a promising approach for reducing cutting temperatures, increasing tool life and improving the workpiece surface integrity. Unfortunately, the cooling fluid tends to evaporate within the supply channel. This induces process variations and hinders the use of nitrogen cooling in commercial applications. In this work, the coolant is applied via the tool’s rake face during orthogonal turning of Ti-6Al-4V. The effect of a nitrogen supply pressure adjustment and a subcooler usage—proposed here for the first time for machining—is analyzed in terms of process forces, tool temperatures and wear patterns, taken dry cutting as a reference. Thereby, reliable cooling strategies are identified for cryogenic cutting
Direkte Patienteninformation für verschreibungspflichtige Arzneitmittel: internationale Erfahrungen und Optionen für Deutschland
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Considering the Influence of Minimum Quantity Lubrication for Modelling Changes in Temperature, Forces and Phase Transformations during Machining
The frontotemporal dementia mutation R406W blocks tau’s interaction with the membrane in an annexin A2–dependent manner
The R406W mutation prevents tau from functioning as a linker between the membrane and the microtubule cytoskeleton
Antimicrobial use in pediatric oncology and hematology in Germany and Austria, 2020/2021: a cross-sectional, multi-center point-prevalence study with a multi-step qualitative adjudication process
Background
Due to the high risk of severe infection among pediatric hematology and oncology patients, antimicrobial use is particularly high. With our study, we quantitatively and qualitatively evaluated, based on institutional standards and national guidelines, antimicrobial usage by employing a point-prevalence survey with a multi-step, expert panel approach. We analyzed reasons for inappropriate antimicrobial usage.
Methods
This cross-sectional study was conducted at 30 pediatric hematology and oncology centers in 2020 and 2021. Centers affiliated to the German Society for Pediatric Oncology and Hematology were invited to join, and an existing institutional standard was a prerequisite to participate. We included hematologic/oncologic inpatients under 19 years old, who had a systemic antimicrobial treatment on the day of the point prevalence survey. In addition to a one-day, point-prevalence survey, external experts individually assessed the appropriateness of each therapy. This step was followed by an expert panel adjudication based upon the participating centers’ institutional standards, as well as upon national guidelines. We analyzed antimicrobial prevalence rate, along with the rate of appropriate, inappropriate, and indeterminate antimicrobial therapies with regard to institutional and national guidelines. We compared the results of academic and non-academic centers, and performed a multinomial logistic regression using center- and patient-related data to identify variables that predict inappropriate therapy.
Findings
At the time of the study, a total of 342 patients were hospitalized at 30 hospitals, of whom 320 were included for the calculation of the antimicrobial prevalence rate. The overall antimicrobial prevalence rate was 44.4% (142/320; range 11.1–78.6%) with a median antimicrobial prevalence rate per center of 44.5% (95% confidence interval [CI] 35.9–49.9). Antimicrobial prevalence rate was significantly higher (p < 0.001) at academic centers (median 50.0%; 95% CI 41.2–55.2) compared to non-academic centers (median 20.0%; 95% CI 11.0–32.4). After expert panel adjudication, 33.8% (48/142) of all therapies were labelled inappropriate based upon institutional standards, with a higher rate (47.9% [68/142]) when national guidelines were taken into consideration. The most frequent reasons for inappropriate therapy were incorrect dosage (26.2% [37/141]) and (de-)escalation/spectrum-related errors (20.6% [29/141]). Multinomial, logistic regression yielded the number of antimicrobial drugs (odds ratio, OR, 3.13, 95% CI 1.76–5.54, p < 0.001), the diagnosis febrile neutropenia (OR 0.18, 95% CI 0.06–0.51, p = 0.0015), and an existing pediatric antimicrobial stewardship program (OR 0.35, 95% CI 0.15–0.84, p = 0.019) as predictors of inappropriate therapy. Our analysis revealed no evidence of a difference between academic and non-academic centers regarding appropriate usage.
Interpretation
Our study revealed there to be high levels of antimicrobial usage at German and Austrian pediatric oncology and hematology centers with a significant higher number at academic centers. Incorrect dosing was shown to be the most frequent reason for inappropriate usage. Diagnosis of febrile neutropenia and antimicrobial stewardship programs were associated with a lower likelihood of inappropriate therapy. These findings suggest the importance of febrile neutropenia guidelines and guidelines compliance, as well as the need for regular antibiotic stewardship counselling at pediatric oncology and hematology centers.
Funding
European Society of Clinical Microbiology and Infectious Diseases, Deutsche Gesellschaft für Pädiatrische Infektiologie, Deutsche Gesellschaft für Krankenhaushygiene, Stiftung Kreissparkasse Saarbrücken
Development of the rhopalial nervous system in Aurelia sp.1 (Cnidaria, Scyphozoa)
We examined the development of the nervous system in the rhopalium, a medusa-specific sensory structure, in Aurelia sp.1 (Cnidaria, Scyphozoa) using confocal microscopy. The rhopalial nervous system appears primarily ectodermal and contains neurons immunoreactive to antibodies against tyrosinated tubulin, taurine, GLWamide, and FMRFamide. The rhopalial nervous system develops in an ordered manner: the presumptive gravity-sensing organ, consisting of the lithocyst and the touch plate, differentiates first; the “marginal center,” which controls swimming activity, second; and finally, the ocelli, the presumptive photoreceptors. At least seven bilaterally arranged neuronal clusters consisting of sensory and ganglion cells and their neuronal processes became evident in the rhopalium during metamorphosis to the medusa stage. Our analysis provides an anatomical framework for future gene expression and experimental studies of development and functions of scyphozoan rhopalia
Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine
[This corrects the article DOI: 10.1186/s13054-016-1208-6.]
Imaging standardization in metastatic colorectal cancer : a joint EORTC-ESOI-ESGAR expert consensus recommendation
Background: Treatment monitoring in metastatic colorectal cancer (mCRC) relies on imaging
to evaluate the tumor burden. Response Evaluation Criteria in Solid Tumors (RECIST) provide
a framework on reporting and interpretation of imaging findings yet offer no guidance on a
standardized imaging protocol tailored to mCRC patients. Imaging protocol heterogeneity
remains a challenge for the reproducibility of conventional imaging endpoints and is an
obstacle for research on novel imaging endpoints.
Patients and methods: Acknowledging the recently highlighted potential of radiomics and
artificial intelligence (AI) tools as decision support for patient care in mCRC, a multidisciplinary,
international, and expert panel of imaging specialists was formed to find consensus on mCRC
imaging protocols using the Delphi method.
Results: Under the guidance of the European Organisation for Research and Treatment of
Cancer (EORTC) Imaging and Gastrointestinal Tract Cancer Groups, the European Society of
Oncologic Imaging (ESOI) and the European Society of Gastrointestinal and Abdominal
Radiology (ESGAR), the EORTC-ESOI-ESGAR core imaging protocol was identified.
Conclusion: This consensus protocol attempts to promote standardization and to diminish
variations in patient preparation, scan acquisition and scan reconstruction. We anticipate that
this standardization will increase reproducibility of radiomics and AI studies and serve as a
catalyst for future research on imaging endpoints. For ongoing and future mCRC trials, we
encourage principal investigators to support the dissemination of these imaging standards
across recruiting centers.peer-reviewe
Impaired GABAergic transmission and altered hippocampal synaptic plasticity in collybistin-deficient mice
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