247 results on '"Kaspar S"'
Search Results
2. A new graph labeling with Tribonacci, Fibonacci and Triangular numbers
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Ignatius, Fredrick and Kaspar, S.
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- 2024
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3. Logistic regression and artificial neural network: A comparative study in diagnosing breast cancer
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Hameed, W. Abdul, Anuradha, D., and Kaspar, S.
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- 2021
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4. A Single Assignment of Numbers for Square Divisor Cordial and Cube Divisor Cordial Labelings on the Generalized Petersen Graphs GP (n, 3)
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Ignatius, Fredrick, primary and Kaspar, S, additional
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- 2023
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5. A single assignment of numbers for square divisor cordial and cube divisor cordial labelings on the generalized Petersen graphs GP (n,3)
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Ignatius, Fredrick and Kaspar, S
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In this paper, a work on the generalized Petersen graph GP (n,3) is done, proving Generalized Petersen graph GP (n,3) to be both Square Divisor Cordial Graphs and Cube Divisor Cordial Graphs by a single assignment of numbers on the same graph. Few conditions are provided to label the graphs in single assignment to prove two different labelings. A rule is developed to label the graphs and the results obtained are tabulated by actual verification for n=4 to n=30 but the rule holds good for all n≥ 4. Further, a few illustrations are provided to justify the rule given to label the graphs in a single assignment. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Neuronal current imaging of epileptic activity: An MRI study in patients with a first unprovoked epileptic seizure
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Baudouin Zongxin Jin, Milena Capiglioni, Andrea Federspiel, Uzeyir Ahmadli, Kaspar Schindler, Claus Kiefer, and Roland Wiest
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first seizure ,high frequency oscillations ,MRI ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Objective This study evaluates the performance of the novel MRI sequence stimulus‐induced rotary saturation (SIRS) to map responses to interictal epileptic activity in the human cortex. Spin‐lock pulses have been applied to indirectly detect neuronal activity through magnetic field perturbations. Following initial reports about the feasibility of the method in humans and animals with epilepsy, we aimed to investigate the diagnostic yield of spin‐lock MR pulses in comparison with scalp‐EEG in first seizure patients. Methods We employed a novel method for measurements of neuronal activity through the detection of a resonant oscillating field, stimulus‐induced rotary saturation contrast (SIRS) at spin‐lock frequencies of 120 and 240 Hz acquired at a single 3T MRI system. Within a prospective observational study, we conducted SIRS experiments in 55 patients within 7 days after a suspected first unprovoked epileptic seizure and 61 healthy control subjects. In this study, we report on the analysis of data from a single 3T MRI system, encompassing 35 first seizure patients and 31 controls. Results The SIRS method was applicable in all patients and healthy controls at frequencies of 120 and 240 Hz. We did not observe any significant age‐ or sex‐related differences. Specificity of SIRS at 120 Hz was 90.3% and 93.5% at 240 Hz. Sensitivity was 17.1% at 120 Hz and 40.0% at 240 Hz. Significance SIRS targets neuronal oscillating magnetic fields in patients with epilepsy. The coupling of presaturated spins to epilepsy‐related magnetic field perturbations may serve as a—at this stage experimental—diagnostic test in first seizure patients to complement EEG findings as a standard screening test. Plain Language Summary Routine diagnostic tests carry several limitations when applied after a suspected first seizure. SIRS is a noninvasive MRI method to enable time‐sensitive diagnosis of image correlates of epileptic activity with increased sensitivity compared to routine EEG.
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- 2024
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7. Rainfall prediction using ensembled-LSTM and dense networks
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Sinha, Ujjwal, primary, Thakur, Vishal, additional, Jain, Sammed, additional, Parimala, M., additional, and Kaspar, S., additional
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- 2023
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8. Logistic Regression and Artificial Neural Network: A Comparative Study in Diagnosing Breast Cancer
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W. Abdul Hameed, Anuradha D., and Kaspar S.
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Pharmacology (medical) ,Pharmacology, Toxicology and Pharmaceutics (miscellaneous) - Abstract
Breast tumor is a common problem in gynecology. A reliable test for preoperative discrimination between benign and malignant breast tumor is highly helpful for clinicians in culling the malignant cells through felicitous treatment for patients. This paper is carried out to generate and estimate both logistic regression technique and Artificial Neural Network (ANN) technique to predict the malignancy of breast tumor, utilizing Wisconsin Diagnosis Breast Cancer Database (WDBC). Our aim in this Paper is: (i) to compare the diagnostic performance of both methods in distinguishing between malignant and benign patterns, (ii) to truncate the number of benign cases sent for biopsy utilizing the best model as an auxiliary implement, and (iii) to authenticate the capability of each model to recognize incipient cases as an expert system.
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- 2021
9. The cytoskeletal protein LASP-1 differentially regulates migratory activities of choriocarcinoma cells
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Segerer, S. E., Bartmann, C., Kaspar, S., Müller, N., Kapp, M., Butt, E., and Kämmerer, U.
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- 2016
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10. A harmonized occupational biomonitoring approach
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Nancy B. Hopf, Christophe Rousselle, Devika Poddalgoda, Farida Lamkarkach, Jos Bessems, Kaspar Schmid, Kate Jones, Koki Takaki, Ludwine Casteleyn, Maryam Zare Jeddi, Michael Bader, Michael Koller, Patience Browne, Rex FitzGerald, Susana Viegas, Thomas Göen, Tiina Santonen, Virpi Väänänen, Radu - Corneliu Duca, and Robert Pasanen-Kase
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Biological monitoring ,Exposure biomarkers ,Effect biomarkers ,Risk assessment ,Risk management ,Toxicokinetics ,Environmental sciences ,GE1-350 - Abstract
Biomonitoring has been widely used in assessing exposures in both occupational and public health complementing chemical risk assessments because it measures the concentrations of chemical substances in human body fluids (e.g., urine and blood). Biomonitoring considers all routes and sources of exposure. An occupational biomonitoring guidance document has been elaborated (OECD Occupational Biomonitoring Guidance) within the OECD framework and specifically, the Working Parties on Exposure and Hazard Assessment by scientific experts from 40 institutes and organizations representing 15 countries. The guidance provides practical information for assessing chemical exposures in occupational settings including the three common routes of exposure: inhalation, skin absorption and ingestion due to hand to mouth contact. The elaborated stepwise approach for conducting biomonitoring is tailored for occupational health professionals, scientists, risk assessors, and regulators. It includes methods for selecting appropriate biomarkers, devising sampling strategies, and assessing laboratories for validated analytical methods for the biomarker of interest, and ensuring timely feedback of results. Furthermore, it describes procedures for setting up efficient biomonitoring programs based on the Similar Exposure Group (SEG) approaches. Derived health-based human exposure biomarker assessment values called Occupational Biomonitoring Levels (OBLs) are proposed for use in occupational exposure and risk assessment. It also helps with the interpretation of biomonitoring results routinely collected and procedures for communicating biomonitoring results at individual, collective, and workplace levels. Ethical considerations associated with biomonitoring are also discussed. The ultimate goal of this biomonitoring approach is to promote harmonized application and interpretation of biomarkers as well as evidence-based occupational risk management measures.
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- 2024
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11. Active few-shot learning for rare bioacoustic feature annotation
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Ben McEwen, Kaspar Soltero, Stefanie Gutschmidt, Andrew Bainbridge-Smith, James Atlas, and Richard Green
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Active learning ,Audio classification ,Bioacoustics ,Few-shot learning ,Machine learning ,Information technology ,T58.5-58.64 ,Ecology ,QH540-549.5 - Abstract
The collection and annotation of bioacoustic data present several challenges to researchers. Bioacoustic monitoring of rare (sparse) or cryptic species generally encounter two main issues. The cost of collecting and processing field data and a lack of labelled datasets for the target species. The detection of invasive species incursions and probability of absence testing is especially challenging due to these species having population densities at or close to zero. We present a methodology specifically designed to aid in the analysis of rare acoustic events within long-term field recordings. This approach combines a wavelet-based segmentation method that automatically extracts transient features from within-field recordings. A few-shot active learning recommender system in a human-in-the-loop process prioritises the annotation of low-certainty samples. This process combines the accuracy of human classification and the speed of computational tools to greatly reduce the presence of non-target features in field recordings. We evaluate this approach using an invasive species identification case study. This methodology achieves a test accuracy of 98.4% as well as 81.2% test accuracy using 2-shot, 2-way prototypical learning without fine-tuning, demonstrating high performance at varying data availability contexts. Active learning using low-certainty samples achieves >90% test accuracy using only 20 training samples compared to 80 samples without active learning. This approach allows users to train custom audio classification models for any application with rare features. The model can be easily exported for use in the field making real-time bioacoustic monitoring of less-vocal species a possibility. All code and data are available at https://github.com/Listening-Lab/Annotator.
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- 2024
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12. Multi-site voxel-based morphometry — Not quite there yet
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Focke, N.K., Helms, G., Kaspar, S., Diederich, C., Tóth, V., Dechent, P., Mohr, A., and Paulus, W.
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- 2011
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13. Recent progress in liquid chromatography-based separation and label-free quantitative plant proteomics
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Matros, A., Kaspar, S., Witzel, K., and Mock, H.-P.
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- 2011
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14. Health of singleton neonates in Switzerland through time and crises: a cross-sectional study at the population level, 2007-2022
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Mathilde Le Vu, Katarina L. Matthes, Marek Brabec, Julien Riou, Veronika W. Skrivankova, Irene Hösli, Sabine Rohrmann, and Kaspar Staub
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Birth weight ,Neonatal health ,Crises ,COVID-19 ,Pandemics ,Gynecology and obstetrics ,RG1-991 - Abstract
Abstract Background Being exposed to crises during pregnancy can affect maternal health through stress exposure, which can in return impact neonatal health. We investigated temporal trends in neonatal outcomes in Switzerland between 2007 and 2022 and their variations depending on exposure to the economic crisis of 2008, the flu pandemic of 2009, heatwaves (2015 and 2018) and the COVID-19 pandemic. Methods Using individual cross-sectional data encompassing all births occurring in Switzerland at the monthly level (2007-2022), we analysed changes in birth weight and in the rates of preterm birth (PTB) and stillbirth through time with generalized additive models. We assessed whether the intensity or length of crisis exposure was associated with variations in these outcomes. Furthermore, we explored effects of exposure depending on trimesters of pregnancy. Results Over 1.2 million singleton births were included in our analyses. While birth weight and the rate of stillbirth have remained stable since 2007, the rate of PTB has declined by one percentage point. Exposure to the crises led to different results, but effect sizes were overall small. Exposure to COVID-19, irrespective of the pregnancy trimester, was associated with a higher birth weight (+12 grams [95% confidence interval (CI) 5.5 to 17.9 grams]). Being exposed to COVID-19 during the last trimester was associated with an increased risk of stillbirth (odds ratio 1.24 [95%CI 1.02 to 1.50]). Exposure to the 2008 economic crisis during pregnancy was not associated with any changes in neonatal health outcomes, while heatwave effect was difficult to interpret. Conclusion Overall, maternal and neonatal health demonstrated resilience to the economic crisis and to the COVID-19 pandemic in a high-income country like Switzerland. However, the effect of exposure to the COVID-19 pandemic is dual, and the negative impact of maternal infection on pregnancy is well-documented. Stress exposure and economic constraint may also have had adverse effects among the most vulnerable subgroups of Switzerland. To investigate better the impact of heatwave exposure on neonatal health, weekly or daily-level data is needed, instead of monthly-level data.
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- 2024
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15. The Need to Analyse Historical Mortality Data to Understand the Causes of Today’s Health Inequalities
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Katarina L. Matthes and Kaspar Staub
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population health ,historical demography ,historical epidemiology ,inequality ,population-based cohort studies ,Public aspects of medicine ,RA1-1270 - Published
- 2024
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16. Standardisation of Parameters during Endovenous Laser Therapy of Truncal Varicose Veins - Experimental Ex-vivo Study
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Kaspar, S., Siller, J., Cervinkova, Z., and Danek, T.
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- 2007
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17. Economically Efficient Hepatitis C Virus Treatment Prioritization Improves Health Outcomes
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Shan Liu, Lauren E. Cipriano, Jeremy D. Goldhaber-Fiebert, Kaspar S. Shahzada, and Mark Holodniy
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Adult ,Male ,Economic efficiency ,Prioritization ,Total cost ,Cost-Benefit Analysis ,Hepatitis C virus ,Clinical Decision-Making ,Hepacivirus ,Population health ,medicine.disease_cause ,Health outcomes ,Antiviral Agents ,Article ,Resource Allocation ,03 medical and health sciences ,0302 clinical medicine ,Environmental health ,Outcome Assessment, Health Care ,medicine ,Humans ,030212 general & internal medicine ,Aged ,Health Services Needs and Demand ,Population Health ,business.industry ,Health Policy ,Cost-effectiveness analysis ,Hepatitis C, Chronic ,Middle Aged ,United States ,3. Good health ,Resource allocation ,Female ,030211 gastroenterology & hepatology ,Quality-Adjusted Life Years ,business - Abstract
Background. The total cost of treating the 3 million Americans chronically infected with hepatitis C virus (HCV) represents a substantial affordability challenge requiring treatment prioritization. This study compares the health and economic outcomes of alternative treatment prioritization schedules. Methods. We developed a multiyear HCV treatment budget allocation model to evaluate the tradeoffs of 7 prioritization strategies. We used optimization to identify the priority schedule that maximizes population net monetary benefit (NMB). We compared prioritization schedules in terms of the number of individuals treated, the number of individuals who progress to end-stage liver disease (ESLD), and population total quality-adjusted life years (QALYs). We applied the model to the population of treatment-naive patients with a total annual HCV treatment budget of US$8.6 billion. Results. First-come, first-served (FCFS) treats the fewest people with advanced fibrosis, prevents the fewest cases of ESLD, and gains the fewest QALYs. A schedule developed from optimizing population NMB prioritizes treatment in the first year to patients with moderate to severe fibrosis who are younger than 65 years, followed by older individuals with moderate to severe fibrosis. While this strategy yields the greatest population QALYs, prioritization by disease severity alone prevents more cases of ESLD. Sensitivity analysis indicated that the differences between prioritization schedules are greater when the budget is smaller. A 10% annual treatment price reduction enabled treatment 1 year sooner to several patient subgroups, specifically older patients and those with less severe liver fibrosis. Conclusion. In the absence of a sufficient budget to treat all patients, explicit prioritization targeting younger people with more severe disease first provides the greatest health benefits. We provide our spreadsheet model so that decision makers can compare health tradeoffs of different budget levels and various prioritization strategies with inputs tailored to their population.
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- 2018
18. Rainfall prediction using ensembled-LSTM and dense networks
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Kaspar, S., primary, Parimala, M., additional, Jain, Sammed, additional, Thakur, Vishal, additional, and Sinha, Ujjwal, additional
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- 2021
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19. An Unwanted but Long-Known Company: Post-Viral Symptoms in the Context of Past Pandemics in Switzerland (and Beyond)
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Kaspar Staub, Tala Ballouz, and Milo Puhan
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historical epidemiology ,long COVID ,historical trends ,pandemic ,influenza ,Public aspects of medicine ,RA1-1270 - Abstract
Objectives: Some people do not fully recover from an acute viral infection and experience persistent symptoms or incomplete recovery for months or even years. This is not unique to the SARS-CoV-2 virus and history shows that post-viral conditions like post COVID-19 condition, also referred to as Long Covid, are not new. In particular, during and after pandemics caused by respiratory viruses in which large parts of the population were infected or exposed, professional and public attention was increased, not least because of the large number of people affected.Methods: Given the current relevance of the topic, this article aims to narratively review and summarize the literature on post-viral symptoms during past pandemics and to supplement and illustrate it with Swiss examples from the pandemics of 1890, 1918–1920 and later.Results: Post-viral diseases were an increasingly emphasised health topic during and after past pandemics triggered by respiratory infections over the last 150 years.Conclusion: In the next pandemic, it should not be surprising that post-viral conditions will again play a role, and pandemic plans should reflect this.
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- 2024
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20. Influence of relative humidity in sensing halogenated hydrocarbons with Reflectometric Interference Spectroscopy (RIfS)
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Kaspar, S., Rathgeb, F., Nopper, D., and Gauglitz, G.
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- 1999
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21. The phosphinomethylmalate isomerase gene pmi, encoding an aconitase-like enzyme, is involved in the synthesis of phosphinothricin tripeptide in Streptomyces viridochromogenes
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Heinzelmann, E., Kienzlen, G., Kaspar, S., Recktenwald, J., Wohlleben, W., and Schwartz, D.
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Streptomyces -- Research ,Microbial enzymes -- Research ,Antitoxins -- Research ,Biological sciences - Abstract
Researchers have discovered an enzyme in Streptomyces viridochromogenes Tu494 that is similar to aconitases from plants, bacteria, and fungi. This enzyme is involved in the biosynthesis of the antibiotic phosphinothricin tripeptide.
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- 2001
22. Inactivation of the tricarboxylic acid cycle aconitase gene from Streptomyces viridochromogenes Tu494 impairs morphological and physiological differentiation
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Schwartz, D., Kaspar, S., Kienzlen, G., Muschko, K., and Wohlleben, W.
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Gene mutations -- Physiological aspects ,Scanning electron microscopes -- Usage ,Streptomyces -- Research ,Antibiotics -- Physiological aspects ,Biological sciences - Abstract
Results show that the aconitase gene (acnA) induces aerial mycelium development and sporulation and the gene product AcnA catalyzes isomerization of citrate to isocitrate and phosphinothricin antibiotic production as indicated by Streptomyces viridochromogenes acnA mutants.
- Published
- 1999
23. Innovative Integration of Dual Quantum Cascade Lasers on Silicon Photonics Platform
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Dongbo Wang, Harindra Kumar Kannojia, Pierre Jouy, Etienne Giraud, Kaspar Suter, Richard Maulini, David Gachet, Léo Hetier, Geert Van Steenberge, and Bart Kuyken
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silicon photonics ,flip-chip integration ,quantum cascade laser ,mid-infrared spectroscopy ,Mechanical engineering and machinery ,TJ1-1570 - Abstract
For the first time, we demonstrate the hybrid integration of dual distributed feedback (DFB) quantum cascade lasers (QCLs) on a silicon photonics platform using an innovative 3D self-aligned flip-chip assembly process. The QCL waveguide geometry was predesigned with alignment fiducials, enabling a sub-micron accuracy during assembly. Laser oscillation was observed at the designed wavelength of 7.2 μm, with a threshold current of 170 mA at room temperature under pulsed mode operation. The optical output power after an on-chip beam combiner reached sub-milliwatt levels under stable continuous wave operation at 15 °C. The specific packaging design miniaturized the entire light source by a factor of 100 compared with traditional free-space dual lasers module. Divergence values of 2.88 mrad along the horizontal axis and 1.84 mrad along the vertical axis were measured after packaging. Promisingly, adhering to i-line lithography and reducing the reliance on high-end flip-chip tools significantly lowers the cost per chip. This approach opens new avenues for QCL integration on silicon photonic chips, with significant implications for portable mid-infrared spectroscopy devices.
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- 2024
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24. Infection in hip arthroplasty after previous injection of steroid
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Kaspar, S. and de V de Beer, J.
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- 2005
25. Ambulatory phlebectomy – actual status
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Kaspar, S
- Published
- 2002
26. Trends of physical fitness related to weight status: An analysis including over 412,000 Swiss young male conscripts from 2007 to 2022
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Cédric Gubelmann, Zeno Stanga, Kaspar Staub, and Pedro Marques-Vidal
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Physical fitness ,Obesity ,Weight status ,Army ,Conscription ,Trend ,Medicine - Abstract
Objective: The high prevalence of obesity among young adults in the civilian population pose challenges in recruiting physically fit soldiers. We assessed the trend of physical fitness related to weight status among Swiss male conscripts. Methods: Cross-sectional data of medical examination data during mandatory conscription for the Swiss Armed Forces, 2007–2022 (N = 412,186). The conscription physical test (CPT) assessed five aspects of physical fitness, each aspect scoring 0–25, one component being an endurance test (ET). CPT and ET categories were defined as per military guidelines: “Insufficient”, “Sufficient”, “Good”, “Very Good” and “Excellent”. Weight status was based on body mass index (BMI). Results: Conscripts with obesity (BMI ≥ 30 kg/m2) and overweight (BMI 25–29.99) had significantly (p
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- 2024
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27. Exposure assessment during paint spraying and drying using PTR-ToF-MS
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Srdjan Sabic, David Bell, Bojan Gasic, Kaspar Schmid, Thomas Peter, and Claudia Marcolli
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spraying applications ,workplace exposure ,proton transfer reaction time-of-flight mass spectrometry ,volatile organic compounds ,exposure models ,Public aspects of medicine ,RA1-1270 - Abstract
Spraying is a common way to distribute occupational products, but it puts worker's health at risk by exposing them to potentially harmful particles and gases. The objective of this study is to use time-resolved measurements to gain an understanding of spray applications at the process level and to compare them to predictions of exposure models. We used proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS) at 1-s time resolution to monitor the gas phase concentration of the solvents acetone, ethanol, butyl acetate, xylene and 1-methoxy-2-propy acetate during outdoor spraying and indoor drying of metal plate under various conditions of outdoor air supply. We found that during spraying, gas-phase exposure was dominated by the more volatile solvents acetone and ethanol, which exhibited strong concentration variations due to the outdoor winds. During drying, exposure strongly depended on the strength of ventilation. Under conditions with high supply of outdoor air, our measurements show a near-exponential decay of the solvent concentrations during drying. Conversely, under conditions without outdoor air supply, the drying process required hours, during which the less volatile solvents passed through a concentration maximum in the gas phase, so that the exposure during drying exceeded the exposure during spraying. The concentrations measured during spraying were then compared for each of the substances individually with the predictions of the exposure models ECETOC TRA, Stoffenmanager, and ART using TREXMO. For these conditions, ECETOC TRA and Stoffenmanager predicted exposures in the measured concentration range, albeit not conservative for all solvents and each application. In contrast, ART largely overestimated the exposure for the more volatile solvents acetone and ethanol and slightly underestimated exposure to 1M2PA for one spraying. ECETOC TRA and ART do not have options to predict exposure during drying. Stoffenmanager has the option to predict drying together with spraying, but not to predict the drying phase independently. Our study demonstrates the importance of considering both the spray cloud and solvent evaporation during the drying process. To improve workplace safety, there is a critical need for enhanced exposure models and comprehensive datasets for calibration and validation covering a broader range of exposure situations.
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- 2024
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28. Modified iliofemoral approach for major isolated acetabular revision arthroplasty
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Kaspar, S., Winemaker, M.J., and de V. de Beer, J.
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- 2003
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29. P261 Frequency of B-cell subsets in infliximab-treated paediatric IBD patients
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Schnell, A, primary, Schwarz, B, additional, Wahlbuhl-Becker, M, additional, Allabauer, I, additional, Rechenauer, T, additional, Siebenlist, G, additional, Kaspar, S, additional, Ehrsam, C, additional, Rückel, A, additional, Rascher, W, additional, and Hörning, A, additional
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- 2019
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30. The International Master of Advanced Studies (MAS) in Sleep Medicine of the Universities of Bern and Svizzera Italiana
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Claudio L. A. Bassetti, Felicitas Sohm, Antoine Adamantidis, Kaspar Schindler, Fabrizio Barazzoni, and Mauro Manconi
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sleep ,Bern ,USI ,Switzerland ,education ,teaching ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Introduction: Sleep–wake circadian disorders (SWCDs) are very frequent and linked to major negative effects on the body, mental health, the brain, and on occupational and societal health. The prevention, diagnosis, and treatment of SWCDs and the promotion of sleep health require the sufficient education of general practitioners, specialists, and other health professionals. Unfortunately, education at pre- and postgraduate level is insufficient in most countries across the world. Aims and methods: This article describes the historical context, basic considerations, and methodological approach for the creation of the International Postgraduate Sleep Master by the University of Bern and Svizzera Italiana. Results: The postgraduate Master, which was launched in 2017, is a part-time, flexible course, taken over 2 ½ years, which targets health professionals, scientists, and technicians. After an initial introduction, which is the same for everybody (“common trunk”), the course can be individualized. The 12 modules of the Master include online lectures, schools, internships in a sleep center (in one of our 15 partner universities), case discussions and interactive sessions with students and internationally recognized experts from over 20 countries across the world, and culminates with a Master thesis. The program covers sleep–wake circadian biology; the management of SWCDs; disturbances of consciousness and sleep-related epilepsies; novel approaches in sleep medicine (e.g., clinical trials, telemedicine, data science, artificial intelligence); and topics of increasing relevance (e.g., neurodegenerative disorders, gender and diversity, sleep health, new technologies, artificial intelligence, professional and societal implications). Students are encouraged to also take “crash courses” in preparation for the national, European, and World sleep examinations. Conclusion: The Postgraduate University Sleep Master of the Universities of Bern and Svizzera Italiana offers a unique part-time, (mainly) virtual opportunity to acquire state-of the art knowledge, skills, and professional experiences to prepare for a clinical or scientific career in sleep medicine for physicians, scientists, and other health professionals.
- Published
- 2024
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31. Die Krongelenksarthrodese des Pferdes.
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Heim, Corsin, Sommer, Kaspar S., and Fürst, Anton
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STATISTICAL hypothesis testing , *BONE cysts , *OPERATIVE surgery , *TELEPHONE interviewing , *HORSES , *PROGNOSIS - Abstract
This retrospective case study evaluated proximal interphalangeal joint arthrodesis in 32 horses referred to the Clinic for Equine Surgery, Vetsuisse Faculty, University of Zurich, between 1995 and 2018. The study had three objectives. The first was to evaluate the success rate of four different surgical techniques for arthrodesis to determine the surgical method with the best prognosis based on in-house experience. The second was to test the hypothesis that the prognosis for proximal interphalangeal joint arthrodesis has improved since the introduction of an equine locking compression plate for the proximal interphalangeal joint (PIP-LCP). The third objective was to evaluate the success rate of a pentagonal plate used in a pilot project from 2004 to 2006. The long-term outcomes were determined by telephone interview. The results were presented using descriptive statistics. A total of 18 horses (56%) had osteoarthritis of the proximal interphalangeal joint, ten (31%) had traumatic luxation of the proximal interphalangeal joint and three (10%) had bone cysts. The indication for arthrodesis could not be determined from the history in the remaining horse. A PIP-LCP and additional transarticular lag screws were used in 13 horses (41%) and a dynamic compression plate (DCP) with additional transarticular lag screws was used in 13 other horses (41%). A double-plate technique using two abaxially placed DCPs and an additional transarticular lag screw was used in one horse, and a novel pentagonal plate was used in the remaining 5 horses. Both forelimbs were operated in two horses. The total success rate in terms of soundness at the walk and trot/return to the previous performance level was 22 of 32 (70%). The PIP-LCP technique was successful in 11 of 13 (83%) and the DCP technique in 9 of 13 cases (70%). Of the four horses treated with the pentagonal plate that had sufficient follow-up information, three had to be euthanized; one of the three horses had implant failure, one had implant failure and infection in the same limb and one had implant failure and infection in two different limbs. Ten of the 32 horses (31%) developed an infection, which was associated with the implant in seven horses, seven other horses (22%) had implant failure, three (9%) developed laminitis and one (3%) suffered a fracture of the second phalanx. All horses with bone cysts, eight of ten horses (80%) with traumatic luxation and 11 of 18 horses (60%) with osteoarthritis had a good outcome. Interphalangeal joint arthrodesis in the hind and forelimbs had success rates of 75 and 67%, respectively. The PIP-LCP technique increased the success rate by 13% compared with the older DCP technique. More horses operated with the DCP technique had to be euthanized compared with horses undergoing the PIP-LCP technique. There was no difference between the two techniques with respect to the number of horses returning to the previous performance level. Limitations of this study included the small number of cases, especially the numbers in some subgroups, and therefore statistical significance testing was not done. Furthermore, the anatomical distribution of the lesions was very heterogeneous and made direct comparisons between surgical techniques difficult. [ABSTRACT FROM AUTHOR]
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- 2021
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32. Challenges and best practices for digital unstructured data enrichment in health research: A systematic narrative review.
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Jana Sedlakova, Paola Daniore, Andrea Horn Wintsch, Markus Wolf, Mina Stanikic, Christina Haag, Chloé Sieber, Gerold Schneider, Kaspar Staub, Dominik Alois Ettlin, Oliver Grübner, Fabio Rinaldi, Viktor von Wyl, and University of Zurich Digital Society Initiative (UZH-DSI) Health Community
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Computer applications to medicine. Medical informatics ,R858-859.7 - Abstract
Digital data play an increasingly important role in advancing health research and care. However, most digital data in healthcare are in an unstructured and often not readily accessible format for research. Unstructured data are often found in a format that lacks standardization and needs significant preprocessing and feature extraction efforts. This poses challenges when combining such data with other data sources to enhance the existing knowledge base, which we refer to as digital unstructured data enrichment. Overcoming these methodological challenges requires significant resources and may limit the ability to fully leverage their potential for advancing health research and, ultimately, prevention, and patient care delivery. While prevalent challenges associated with unstructured data use in health research are widely reported across literature, a comprehensive interdisciplinary summary of such challenges and possible solutions to facilitate their use in combination with structured data sources is missing. In this study, we report findings from a systematic narrative review on the seven most prevalent challenge areas connected with the digital unstructured data enrichment in the fields of cardiology, neurology and mental health, along with possible solutions to address these challenges. Based on these findings, we developed a checklist that follows the standard data flow in health research studies. This checklist aims to provide initial systematic guidance to inform early planning and feasibility assessments for health research studies aiming combining unstructured data with existing data sources. Overall, the generality of reported unstructured data enrichment methods in the studies included in this review call for more systematic reporting of such methods to achieve greater reproducibility in future studies.
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- 2023
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33. Economically Efficient Hepatitis C Virus Treatment Prioritization Improves Health Outcomes
- Author
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Cipriano, Lauren E., primary, Liu, Shan, additional, Shahzada, Kaspar S., additional, Holodniy, Mark, additional, and Goldhaber-Fiebert, Jeremy D., additional
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- 2018
- Full Text
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34. Mobile App for Simplifying Life With Diabetes: Technical Description and Usability Study of GlucoMan
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Schmocker, Kaspar S, primary, Zwahlen, Fabian S, additional, and Denecke, Kerstin, additional
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- 2018
- Full Text
- View/download PDF
35. Sensorization of a surgical robotic instrument for force sensing
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Kaspar S. Shahzada, Aaron Yurkewich, Rajni V. Patel, and Ran Xu
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03 medical and health sciences ,0302 clinical medicine ,Fiber Bragg grating ,medicine.diagnostic_test ,Computer science ,030220 oncology & carcinogenesis ,Surgical instrument ,medicine ,Torque ,030204 cardiovascular system & hematology ,Palpation ,Simulation ,Imaging phantom - Abstract
This paper presents the development and application of an approach for sensorizing a surgical robotic instrument for two degree-of-freedom (DOF) lateral force sensing. The sensorized instrument is compatible with the da Vinci® Surgical System and can be used for skills assessment and force control in specific surgical tasks. The sensing technology utilizes a novel layout of four fiber Bragg grating (FBG) sensors attached to the shaft of a da Vinci® surgical instrument. The two cross-section layout is insensitive to error caused by combined force and torque loads, and the orientation of the sensors minimizes the condition number of the instrument’s compliance matrix. To evaluate the instrument’s sensing capabilities, its performance was tested using a commercially available force-torque sensor, and showed a resolution of 0.05N at 1 kHz sampling rate. The performance of the sensorized instrument was evaluated by performing three surgical tasks on phantom tissue using the da Vinci® system with the da Vinci Research Kit (dVRK): tissue palpation, knot tightening during suturing and Hem-O-Lok® tightening during knotless suturing. The tasks were designed to demonstrate the robustness of the sensorized force measurement approach. The paper reports the results of further evaluation by a group of expert and novice surgeons performing the three tasks mentioned above.
- Published
- 2016
36. A Study on Connected Domination Transition Number of a Graph
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Kaspar S, B. Gayathri, D. Kalpanapriya, and M. P. Kulandaivel
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Combinatorics ,Environmental Engineering ,Hardware and Architecture ,General Chemical Engineering ,General Engineering ,Computer Science (miscellaneous) ,Graph (abstract data type) ,Connected domination ,Biotechnology ,Mathematics - Abstract
Since its inception, the notion of domination has found vital roles in several real life applications related to facility locations, representatives’ selection, communication networks, electrical networks, etc. The vast application of the notion has paved the way for the development of the notion with several types. The notion of connected domination is a significant domination parameter amongst the several domination varieties emerged in this domain. The problem of determining limited bus stops in a route was effectively addressed by the connected domination parameter. Most of the biological and neural networks effectively use this notion to solve several problems which require the connectedness of the structures. In view of the growing applications of the variant, several researchers and scholars have published numerous research articles on the said parameter. Recently, some researchers attempted on transition of the domination parameter into a connected one. In order to facilitate this transition, another variant viz., connected domination transition number was introduced and its properties and bounds were studied. In this article we explore more properties and bounds of the parameter connected domination transition number for special types of graphs. We also characterize the instances at which the domination and connected domination parameters would be same for few types of graphs. We also attempted to derive few Nordhaus–Gaddum (NG) type results for the same.
- Published
- 2018
37. Multiple point criticality principle and Coleman-Weinberg inflation
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Antonio Racioppi, Jürgen Rajasalu, and Kaspar Selke
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Cosmology of Theories BSM ,Early Universe Particle Physics ,Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
Abstract We apply the multiple point criticality principle to inflationary model building and study Coleman-Weinberg inflation when the scalar potential is quadratic in the logarithmic correction. We analyze also the impact of a non-minimal coupling to gravity under two possible gravity formulation: metric or Palatini. We compare the eventual compatibility of the results with the final data release of the Planck mission.
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- 2022
- Full Text
- View/download PDF
38. Mobile App for Simplifying Life With Diabetes: Technical Description and Usability Study of GlucoMan
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Kaspar S Schmocker, Fabian S Zwahlen, and Kerstin Denecke
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diabetes management ,Process (engineering) ,Computer science ,Endocrinology, Diabetes and Metabolism ,Interoperability ,Biomedical Engineering ,030209 endocrinology & metabolism ,Health Informatics ,03 medical and health sciences ,0302 clinical medicine ,Documentation ,Health Information Management ,Diabetes management ,Human–computer interaction ,self-care ,chronic disease management ,030212 general & internal medicine ,mobile health ,Requirements analysis ,mobile apps ,Original Paper ,Data collection ,business.industry ,Continuous monitoring ,Usability ,patient empowerment ,Computer Science Applications ,diabetes mellitus ,business - Abstract
Background: Patients with diabetes can be affected by several comorbidities that require immediate action when occurring as they may otherwise cause fatal or consequential damage. For this reason, patients must closely monitor their metabolism and inject insulin when necessary. The documentation of glucose values and other relevant measurements is often still on paper in a diabetes diary. Objective: The goal of this work is to develop and implement a novel mobile health system for the secure collection of relevant data referring to a person’s metabolis and to digitize the diabetes diary to enable continuous monitoring for both patients and treating physicians. One specific subgoal is to enable data transmission of health parameters to secure data storage. Methods: The process of implementing the system consists of (1) requirements analysis with patients and physicians to identify patient needs and specify relevant functionalities, (2) design and development of the app and the data transmission, and (3) usability study. Results: We developed and implemented the mobile app GlucoMan to support data collection pertaining to a person’s metabolism. An automated transfer of measured values from a glucometer was implemented. Medication and nutrition data could be entered using product barcodes. Relevant background knowledge such as information on carbohydrates was collected from existing databases. The recorded data was transmitted using international interoperability standards to the MIDATA.coop storage platform. The usability study revealed some design issues that needs to be solved, but in principle, the study results show that the app is easy to use and provides useful features. Conclusions: Data collection on a patient’s metabolism can be supported with a multifunctional app such as GlucoMan. Besides monitoring, continuous data can be documented and made available to the treating physician. GlucoMan allows patients to monitor disease-relevant parameters and decide who accesses their health data. In this way, patients are empowered not only to manage diabetes but also manage their health data.
- Published
- 2018
39. Mobile App for Simplifying Life With Diabetes: Technical Description and Usability Study of GlucoMan
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Schmocker, Kaspar S, primary, Zwahlen, Fabian S, additional, and Denecke, Kerstin, additional
- Published
- 2017
- Full Text
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40. Anterior accessory great saphenous vein treated with endovenous laser
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Kaspar, S., primary
- Published
- 2017
- Full Text
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41. Reinfections and Cross-Protection in the 1918/19 Influenza Pandemic: Revisiting a Survey Among Male and Female Factory Workers
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Katarina L. Matthes, Mathilde Le Vu, Urmila Bhattacharyya, Antonia Galliker, Maryam Kordi, Joël Floris, and Kaspar Staub
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immunity ,Spanish flu ,multi-wave pandemic ,sex differences ,health history ,Public aspects of medicine ,RA1-1270 - Abstract
Objectives: The COVID-19 pandemic highlights questions regarding reinfections and immunity resulting from vaccination and/or previous illness. Studies addressing related questions for historical pandemics are limited.Methods: We revisit an unnoticed archival source on the 1918/19 influenza pandemic. We analysed individual responses to a medical survey completed by an entire factory workforce in Western Switzerland in 1919.Results: Among the total of n = 820 factory workers, 50.2% reported influenza-related illness during the pandemic, the majority of whom reported severe illness. Among male workers 47.4% reported an illness vs. 58.5% of female workers, although this might be explained by varied age distribution for each sex (median age was 31 years old for men, vs. 22 years old for females). Among those who reported illness, 15.3% reported reinfections. Reinfection rates increased across the three pandemic waves. The majority of subsequent infections were reported to be as severe as the first infection, if not more. Illness during the first wave, in the summer of 1918, was associated with a 35.9% (95%CI, 15.7–51.1) protective effect against reinfections during later waves.Conclusion: Our study draws attention to a forgotten constant between multi-wave pandemics triggered by respiratory viruses: Reinfection and cross-protection have been and continue to be a key topic for health authorities and physicians in pandemics, becoming increasingly important as the number of waves increases.
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- 2023
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42. Short-termed changes in quantitative ultrasound estimated bone density among young men in an 18-weeks follow-up during their basic training for the Swiss Armed Forces
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Michael Strässle, Jonas Grossmann, Patrick Eppenberger, Alexander Faas, Ivanka Jerkovic, Joël Floris, Lena Öhrström, Gülfirde Akgül, Lafi Aldakak, Frank Rühli, Nicole Bender, and Kaspar Staub
- Subjects
Bone health ,Follow-up ,Young adults ,Medicine ,Biology (General) ,QH301-705.5 - Abstract
Background Quantitative Ultrasound (QUS) methods have been widely used to assess estimated bone density. This study aimed to assess changes in estimated bone density in association with changes in body composition, physical activity, and anthropometry. Methods We examined changes in anthropometry, body composition, and physical activity associated with changes in estimated bone mineral density (measured using quantitative ultrasound with a heel ultrasound device indicating broadband ultrasound attenuation BUA and speed of sound SOS) in a follow-up sample of n = 73 young men at the beginning and again 18 weeks later at the end of basic military training. Results At the end of the basic training, the subjects were on average significantly heavier (+1.0%), slightly taller (+0.5%) and had a higher fat mass (+6.6%) and grip strength (+8.6%). A significant decrease in mean physical activity (−49.5%) and mean estimated bone density calculated with BUA (−7.5%) was observed in the paired t-test. The results of the multivariable linear regressions (backward selection) show that changes in skeletal muscle mass (delta = 2nd measurement minus 1st measurement) have negative and body weight (delta) have positive association with the speed of sound SOS (delta), while fat mass (delta) and physical activity (delta) had the strongest negative associations with estimated bone mineral density (delta). In particular, we found a negative association between fat mass (delta) and estimated bone mineral density (delta, estimated with BUA). Conclusion Our study suggests that estimated bone density from the calcaneus can change within a few months even in young and mostly healthy individuals, depending upon physical activity levels and other co-factors. Further studies including other troop types as control groups as well as on women should follow in order to investigate this public health relevant topic in more depth. To what extent the estimated bone density measurement with quantitative ultrasound is clinically relevant needs to be investigated in further studies.
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- 2023
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43. Associations between hydration status, body composition, sociodemographic and lifestyle factors in the general population: a cross-sectional study
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Turgut Ekingen, Cynthia Sob, Christina Hartmann, Frank J. Rühli, Katarina L. Matthes, Kaspar Staub, and Nicole Bender
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Body hydration ,Overweight ,BIA ,Sex differences ,Physical activity ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Whole-body hydration status is associated with several health outcomes, such as dehydration, edema and hypertension, but little is known about the nonclinical determinants. Therefore, we studied the associations of sex, age, body composition, nutrition, and physical activity on several body hydration measures. Methods We assessed sociodemographic variables, dietary habits, and physical activity by questionnaire and body composition by bioelectric impedance analysis (BIA). We compared determinants between the sexes and calculated associations between determinants and BIVA hydration measures by multivariable linear regressions. Results A total of 242 adults from the general population (age 18–94, 47% women) were included. Women were younger, smaller, lighter, and had a smaller BMI (kg/m2) than men (p
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- 2022
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44. Health of neonates born in the maternity hospital in Bern, Switzerland, 1880–1900 and 1914–1922
- Author
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Vivienne Salvisberg, Mathilde Le Vu, Joël Floris, Katarina L. Matthes, and Kaspar Staub
- Subjects
Medicine ,Science - Abstract
The identification of factors impeding normal fetal development and growth is crucial for improving neonatal health. Historical studies are relevant because they show which parameters have influenced neonatal health in the past in order to better understand the present. We studied temporal changes of neonatal health outcomes (birth weight, gestational age, stillbirth rate) and the influence of different cofactors in two time periods. Moreover, we investigated particularly neonatal health in the wake of the 1918/19 influenza pandemic. Data were transcribed from the Bern Maternity Hospital and consists of two time periods: A) The years 1880, 1885, 1890, 1895 and 1900 (N = 1530, births’ coverage 20%); B) The years 1914–1922 (N = 6924, births’ coverage 40–50%). Linear regression models were used to estimate the effect of birth year on birth weight, and logistic regression models to estimate the effect of birth year and of the exposure to the pandemic on premature birth, stillborn and low birth weight (LBW). Mean birth weight increased only minimally between the two datasets; whereas, in the years 1914–1922, the preterm birth and stillbirth rates were markedly reduced compared with the years 1880–1900. Sex, parity, gestational age and maternal age were significantly associated with birth weight in both time periods. The probability of LBW was significantly increased in 1918 (OR 1.49 (95% CI 1.00–2.23)) and in 1919 (OR 1.55 (95% CI 1.02–2.36)) compared to 1914. Mothers who were heavily exposed to the influenza pandemic during pregnancy had a higher risk of stillbirth (OR 2.27 (95% CI 1.32–3.9)). This study demonstrated that factors influencing neonatal health are multifactorial but similar in both time periods. Moreover, the exposure to the 1918/19 pandemic was less associated with LBW and more associated with an increased risk of stillbirth. If this trend is confirmed by further studies, it could indicate some consistency across pandemics, as similar patterns have recently been shown for COVID-19.
- Published
- 2023
45. Sensorization of a surgical robotic instrument for force sensing
- Author
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Shahzada, Kaspar S., additional, Yurkewich, Aaron, additional, Xu, Ran, additional, and Patel, Rajni V., additional
- Published
- 2016
- Full Text
- View/download PDF
46. Endovenous laser therapy of varicose veins – 13-year Czech experience
- Author
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Kaspar, S., primary and Kaspar, D., additional
- Published
- 2016
- Full Text
- View/download PDF
47. Childhood reproductive hormone levels after pediatric hematopoietic stem cell transplantation in relation to adult testicular function
- Author
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Sidsel Mathiesen, Kaspar Sørensen, Marianne Ifversen, Casper P Hagen, Jørgen Holm Petersen, Anders Juul, and Klaus Müller
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pediatrics ,hematopoietic stem cell transplantation ,late effects ,gonadal function ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Objectives: Longitudinal assessment of testicular function after pediatric hematopoietic stem cell transplantation (HSCT) is needed to guide clinical follow-up. We investigated dynamics in male reproductive hormones after pediatric HSCT, focusing on pubertal timing and associations with testosterone deficiency and azoospe rmia in adulthood. Methods: This retrospective, longitudinal study included 39 survivors median 19 years after pediatric HSCT. Serum concentrations of LH, testosterone, FSH, and inhibin B from the time of HSCT, during puberty, and into adulthood were analy zed. Pubertal timing (rise in LH and testosterone) was compared to a reference cohort of 112 healthy boys. Associations between reproductive hormone levels during puberty and adult testicular function (including semen quality) were investigated. Results: Pubertal induction with testosterone was needed in 6/26 patients who were prepubertal at HSCT. In the remaining patients, pubertal timing was comparable to the reference cohort. However, 9/33 patients (without pubertal induction) developed testosterone deficiency in early adulthood, which was associated with higher LH levels from age 14 to 16 years. Azoospermia in adulthood was found in 18/26 patients without testosterone substitution. Higher FSH and lower inhibin B levels from mid-pubertal age were associated with azoospermia in adulthood, in patients bein g prepubertal at HSCT. Conclusion: Our results indicate a substantial risk of deterioration in testicular function after pediatric HSCT, despite normal pubertal timing. Although reproductive hormone levels from mid-puberty indicated adult testicular function, prolonged follow-up into adulthood is needed in these patients, including clinical examination, reproductive hormone analysis, and semen sample for patients interested in their fertility potential.
- Published
- 2021
- Full Text
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48. Body height among adult male and female Swiss Health Survey participants in 2017: Trends by birth years and associations with self-reported health status and life satisfaction
- Author
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Sarah-Maria Müller, Joël Floris, Sabine Rohrmann, Kaspar Staub, and Katarina L Matthes
- Subjects
Stature ,Trend ,Health ,Medicine - Abstract
The increase in adult height for 150 years is linked to overall improvements in nutrition, hygiene, and living standards. Height is positively associated with general health and success on various levels (e.g. quality of life, earnings or happiness). The aim of this study was to investigate whether different subgroups show different trends across birth cohorts. We wanted to know whether taller individuals considered themselves as healthier and their quality of life as better than shorter individuals.We included 19,435 participants from the Swiss population-based Health Survey 2017. GAM were used to assess nonlinear associations between height and birth year. Multinomial logistic regression was used to predict probabilities of self-rated health in relation to height.The increase in average height slows down from the 1970s birth cohorts. Participants with parents from Central/Northern/Western Europe (men 177.9 cm, women: 165.1 cm) or Eastern Europe (men 178.7 cm, women: 165.7 cm) were taller than participants with parents from South America (men 174.3 cm, women: 161. cm) and Asia (men 173.2 cm, women: 160.1 cm). Participants with tertiary education were taller than participants from education levels (mean difference men: 4.5 cm, women: 5.0 cm). Height was positively associated with self-declared aspects of health and life satisfaction.These results support the conclusion that body height as a co-factor of health aspects should be considered in public health research. Although adult body height can no longer be influenced, nutritional status and thus also healthy growth can be influenced in childhood by public health programs, by eliminating social inequalities, and by strengthen healthy living conditions.
- Published
- 2022
- Full Text
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49. Recent advances in 2-µm GaSb-based semiconductor disk laser - power scaling, narrow-linewidth and short-pulse operation
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Kaspar, S., Rattunde, M., Töpper, T., Moser, R., Adler, S., Manz, C., Köhler, K., Wagner, J., and Publica
- Subjects
semiconductor disk laser ,Pound-Drever-Hall laser stabilization ,power scaling ,single-frequency ,VECSEL ,ASE ,amplified spontaneous emission ,cavity dumping ,GaSb-based ,lateral lasing ,narrow-linewidth emission ,multi-chip cavity ,OPSDL ,near-to-mid-infrared laser - Abstract
An overview of the recent progress in 2-µm GaSb-based semiconductor disk laser will be presented in this paper. Significant advances could be recently achieved in scaling the output power as well as in narrow-linewidth and short-pulse operation. Moreover, we will discuss the limiting effect for the output power imposed by laser emission perpendicular to the beam propagation, i.e. lateral lasing, and show means to suppress this phenomenon adversely affecting the laser performance. By using several gain elements in one laser cavity, the demonstration of more than 10 W output power from a GaSb-based SDL will be reported. Furthermore, employing a high-stability setup optimized for single-frequency emission more than 1 W output power at a linewidth below 50 kHz will be shown. Further comprehensive stability analyses were conducted paving the path for future stability improvements. Moreover, electro-optic cavity dumping of disk lasers will be demonstrated to be an effective means for achieving
- Published
- 2013
50. Micro-cavity 2-µm GaSb-based semiconductor disk laser using high-reflectivity SiC heatspreader
- Author
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Kaspar, S., Rattunde, M., Schilling, C., Adler, S., Holl, P., Manz, C., Köhler, K., Wagner, J., and Publica
- Abstract
An optically pumped GaSb-based semiconductor disk laser (SDL) emitting at 2.05 µm has been realized with a very short (380 µm long) laser cavity by high-reflectivity coating the intra-cavity SiC heatspreader, which then serves as the outcoupling mirror. Room-temperature output powers in excess of 750mW have been demonstrated in multimode operation and still 100mW in TEM00 emission, which is a more than 100x increase in output power compared to previous reports on GaSb-based micro-cavity (lC) SDLs. Mode-hop-free tunable single-frequency emission with linewidths
- Published
- 2013
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