LIVIVO - Search results -

Search results

Result 1 - 10 of total 78

Search options

Article: Odderon and proton substructure from a model-independent Lévy imaging of elastic

Csörgő, T / Pasechnik, R / Ster, A

The European physical journal. C, Particles and fields

2019 Volume 79, Issue 1, Page(s) 62

Abstract: We describe a new and model-independent Lévy imaging method of quality fits to the published datasets and reconstruct the amplitude of high- ... ...

Abstract	We describe a new and model-independent Lévy imaging method of quality fits to the published datasets and reconstruct the amplitude of high-energy
Language	English
Publishing date	2019-01-28
Publishing country	France
Document type	Journal Article
ZDB-ID	1459069-4
ISSN	1434-6052 ; 1434-6044
ISSN (online)	1434-6052
ISSN	1434-6044
DOI	10.1140/epjc/s10052-019-6588-8
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.

Article ; Online: Implementation of the trial emulation approach in medical research: a scoping review.

Scola, Giulio / Chis Ster, Anca / Bean, Daniel / Pareek, Nilesh / Emsley, Richard / Landau, Sabine

BMC medical research methodology

2023 Volume 23, Issue 1, Page(s) 186

Abstract: Background: When conducting randomised controlled trials is impractical, an alternative is to carry out an observational study. However, making valid causal inferences from observational data is challenging because of the risk of several statistical ... ...

Abstract	Background: When conducting randomised controlled trials is impractical, an alternative is to carry out an observational study. However, making valid causal inferences from observational data is challenging because of the risk of several statistical biases. In 2016 Hernán and Robins put forward the 'target trial framework' as a guide to best design and analyse observational studies whilst preventing the most common biases. This framework consists of (1) clearly defining a causal question about an intervention, (2) specifying the protocol of the hypothetical trial, and (3) explaining how the observational data will be used to emulate it. Methods: The aim of this scoping review was to identify and review all explicit attempts of trial emulation studies across all medical fields. Embase, Medline and Web of Science were searched for trial emulation studies published in English from database inception to February 25, 2021. The following information was extracted from studies that were deemed eligible for review: the subject area, the type of observational data that they leveraged, and the statistical methods they used to address the following biases: (A) confounding bias, (B) immortal time bias, and (C) selection bias. Results: The search resulted in 617 studies, 38 of which we deemed eligible for review. Of those 38 studies, most focused on cardiology, infectious diseases or oncology and the majority used electronic health records/electronic medical records data and cohort studies data. Different statistical methods were used to address confounding at baseline and selection bias, predominantly conditioning on the confounders (N = 18/49, 37%) and inverse probability of censoring weighting (N = 7/20, 35%) respectively. Different approaches were used to address immortal time bias, assigning individuals to treatment strategies at start of follow-up based on their data available at that specific time (N = 21, 55%), using the sequential trial emulations approach (N = 11, 29%) or the cloning approach (N = 6, 16%). Conclusion: Different methods can be leveraged to address (A) confounding bias, (B) immortal time bias, and (C) selection bias. When working with observational data, and if possible, the 'target trial' framework should be used as it provides a structured conceptual approach to observational research.
MeSH term(s)	Humans ; Biomedical Research ; Selection Bias ; Databases, Factual ; MEDLINE ; Medical Oncology ; Observational Studies as Topic
Language	English
Publishing date	2023-08-16
Publishing country	England
Document type	Review ; Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2041362-2
ISSN	1471-2288 ; 1471-2288
ISSN (online)	1471-2288
ISSN	1471-2288
DOI	10.1186/s12874-023-02000-9
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: Improving analysis practice of continuous adverse event outcomes in randomised controlled trials - a distributional approach.

Chis Ster, Anca / Phillips, Rachel / Sauzet, Odile / Cornelius, Victoria

Trials

2021 Volume 22, Issue 1, Page(s) 419

Abstract: Background: Randomised controlled trials (RCTs) provide valuable information for developing harm profiles but current analysis practices to detect between-group differences are suboptimal. Drug trials routinely screen continuous clinical and biological ... ...

Abstract	Background: Randomised controlled trials (RCTs) provide valuable information for developing harm profiles but current analysis practices to detect between-group differences are suboptimal. Drug trials routinely screen continuous clinical and biological data to monitor participant harm. These outcomes are regularly dichotomised into abnormal/normal values for analysis. Despite the simplicity gained for clinical interpretation, it is well established that dichotomising outcomes results in a considerable reduction in information and thus statistical power. We propose an automated procedure for the routine implementation of the distributional method for the dichotomisation of continuous outcomes proposed by Peacock and Sauzet, which retains the precision of the comparison of means. Methods: We explored the use of a distributional approach to compare differences in proportions based on the comparison of means which retains the power of the latter. We applied this approach to the screening of clinical and biological data as a means to detect 'signals' for potential adverse drug reactions (ADRs). Signals can then be followed-up in further confirmatory studies. Three distributional methods suitable for different types of distributions are described. We propose the use of an automated approach using the observed data to select the most appropriate distribution as an analysis strategy in a RCT setting for multiple continuous outcomes. We illustrate this approach using data from three RCTs assessing the efficacy of mepolizumab in asthma or COPD. Published reference ranges were used to define the proportions of participants with abnormal values for a subset of 10 blood tests. The between-group distributional and empirical differences in proportions were estimated for each blood test and compared. Results: Within trials, the distributions varied across the 10 outcomes demonstrating value in a practical approach to selecting the distributional method in the context of multiple adverse event outcomes. Across trials, there were three outcomes where the method chosen by the automated procedure varied for the same outcome. The distributional approach identified three signals (eosinophils, haematocrit, and haemoglobin) compared to only one when using the Fisher's exact test (eosinophils) and two identified by use of the 95% confidence interval for the difference in proportions (eosinophils and potassium). Conclusion: When dichotomisation of continuous adverse event outcomes aids clinical interpretation, we advocate use of a distributional approach to retain statistical power. Methods are now easy to implement. Retaining information is especially valuable in the context of the analysis of adverse events in RCTs. The routine implementation of this automated approach requires further evaluation.
MeSH term(s)	Asthma ; Drug-Related Side Effects and Adverse Reactions/diagnosis ; Humans ; Randomized Controlled Trials as Topic ; Research Design
Language	English
Publishing date	2021-06-29
Publishing country	England
Document type	Journal Article
ZDB-ID	2040523-6
ISSN	1745-6215 ; 1468-6694 ; 1745-6215
ISSN (online)	1745-6215
ISSN	1468-6694 ; 1745-6215
DOI	10.1186/s13063-021-05343-0
Database	MEDical Literature Analysis and Retrieval System OnLINE

Order via subito

Article ; Online: Evaluating how clear the questions being investigated in randomised trials are: systematic review of estimands.

Cro, Suzie / Kahan, Brennan C / Rehal, Sunita / Chis Ster, Anca / Carpenter, James R / White, Ian R / Cornelius, Victoria R

BMJ (Clinical research ed.)

2022 Volume 378, Page(s) e070146

Abstract: Objectives: To evaluate how often the precise research question being addressed about an intervention (the estimand) is stated or can be determined from reported methods, and to identify what types of questions are being investigated in phase 2-4 ... ...

Abstract	Objectives: To evaluate how often the precise research question being addressed about an intervention (the estimand) is stated or can be determined from reported methods, and to identify what types of questions are being investigated in phase 2-4 randomised trials. Design: Systematic review of the clarity of research questions being investigated in randomised trials in 2020 in six leading general medical journals. Data source: PubMed search in February 2021. Eligibility criteria for selecting studies: Phase 2-4 randomised trials, with no restrictions on medical conditions or interventions. Cluster randomised, crossover, non-inferiority, and equivalence trials were excluded. Main outcome measures: Number of trials that stated the precise primary question being addressed about an intervention (ie, the primary estimand), or for which the primary estimand could be determined unambiguously from the reported methods using statistical knowledge. Strategies used to handle post-randomisation events that affect the interpretation or existence of patient outcomes, such as intervention discontinuations or uses of additional drug treatments (known as intercurrent events), and the corresponding types of questions being investigated. Results: 255 eligible randomised trials were identified. No trials clearly stated all the attributes of the estimand. In 117 (46%) of 255 trials, the primary estimand could be determined from the reported methods. Intercurrent events were reported in 242 (95%) of 255 trials; but the handling of these could only be determined in 125 (49%) of 255 trials. Most trials that provided this information considered the occurrence of intercurrent events as irrelevant in the calculation of the treatment effect and assessed the effect of the intervention regardless (96/125, 77%)-that is, they used a treatment policy strategy. Four (4%) of 99 trials with treatment non-adherence owing to adverse events estimated the treatment effect in a hypothetical setting (ie, the effect as if participants continued treatment despite adverse events), and 19 (79%) of 24 trials where some patients died estimated the treatment effect in a hypothetical setting (ie, the effect as if participants did not die). Conclusions: The precise research question being investigated in most trials is unclear, mainly because of a lack of clarity on the approach to handling intercurrent events. Clear reporting of estimands is necessary in trial reports so that all stakeholders, including clinicians, patients and policy makers, can make fully informed decisions about medical interventions. Systematic review registration: PROSPERO CRD42021238053.
MeSH term(s)	Humans ; Randomized Controlled Trials as Topic
Language	English
Publishing date	2022-08-23
Publishing country	England
Document type	Journal Article ; Systematic Review
ZDB-ID	1362901-3
ISSN	1756-1833 ; 0959-8154 ; 0959-8146 ; 0959-8138 ; 0959-535X ; 1759-2151
ISSN (online)	1756-1833
ISSN	0959-8154 ; 0959-8146 ; 0959-8138 ; 0959-535X ; 1759-2151
DOI	10.1136/bmj-2022-070146
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Ua VI Zs.10: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 2021: Bestellungen von Artikeln über das Online-Bestellformular
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article: Einige kritische Gedanken zur Psoralehre aus heutiger Sicht

Ster, A.

Allgemeine Homöopathische Zeitung

1999 Volume 244, Issue 04, Page(s) 142–143

Language	German
Publishing date	1999-01-01
Publishing place	Stuttgart ; New York
Document type	Article
ZDB-ID	2124175-2
ISSN	1439-8990 ; 1438-2563
ISSN (online)	1439-8990
ISSN	1438-2563
DOI	10.1055/s-2006-936689
Database	Thieme publisher's database

Order via subito

Article ; Online: The effect of hydrodynamic and thermodynamic factors and the addition of citric acid on the precipitation of calcium oxalate dihydrate.

Šter, Anamarija / Šafranko, Silvija / Bilić, Katarina / Marković, Berislav / Kralj, Damir

Urolithiasis

2017 Volume 46, Issue 3, Page(s) 243–256

Abstract: This paper reports on the investigation of experimental conditions relevant for spontaneous precipitation of significant amount of pure calcium oxalate dihydrate (COD). For this purpose, the hydrodynamic and thermodynamic parameters, such as mode of ... ...

Abstract	This paper reports on the investigation of experimental conditions relevant for spontaneous precipitation of significant amount of pure calcium oxalate dihydrate (COD). For this purpose, the hydrodynamic and thermodynamic parameters, such as mode of agitation, temperature, supersaturation and concentration of additives (citrate ions), have been studied. The results show that in the model systems, without the citrate addition and applied mechanical stirring, calcium oxalate monohydrate (COM) was observed as dominant modification after 20 min of aging, while the magnetic stirring resulted in a formation of a mixture of COM and calcium oxalate trihydrate (COT), regardless of the temperature applied. In the mechanically stirred systems, the addition of citrate ions in the range of concentrations, 0.001 mol dm
MeSH term(s)	Calcium Oxalate/chemistry ; Chemical Precipitation ; Citric Acid/chemistry ; Crystallization ; Hydrodynamics ; Microscopy, Electron, Scanning ; Temperature ; Thermodynamics
Chemical Substances	Calcium Oxalate (2612HC57YE) ; Citric Acid (2968PHW8QP)
Language	English
Publishing date	2017-06-23
Publishing country	Germany
Document type	Journal Article
ZDB-ID	2703553-0
ISSN	2194-7236 ; 2194-7228
ISSN (online)	2194-7236
ISSN	2194-7228
DOI	10.1007/s00240-017-0991-0
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 928: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Book ; Online: Bestrijding emelten in grasland 2004

van Rozen, K. / ster, A.

toetsing van chemische en biologische middelen tegen emelten (Tipula spp.) in een veld- en in vitro proef

2004

Keywords	biological control ; chemical control ; grasslands ; pest control ; tipula ; biologische bestrijding ; chemische bestrijding ; graslanden ; plagenbestrijding
Language	Dutch
Publisher	Praktijkonderzoek Plant & Omgeving
Publishing country	nl
Document type	Book ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

Full text online

Full text

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Article: Historical usage of aqueous film forming foam: A case study of the widespread distribution of perfluoroalkyl acids from a military airport to groundwater, lakes, soils and fish

Filipovic, Marko / Andreas Woldegiorgis / Karin NorstrÃ¶m / Momina Bibi / Maria Lindberg / Ann-Helen ÃsterÃ¥s

Chemosphere. 2015 June, v. 129

2015

Abstract: Historical usage of aqueous film forming foams (AFFFs) at military airports is a potential source of perfluoroalkyl acids (PFAAs) to the nearby environment. In this study, the distribution of perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), ...

Abstract	Historical usage of aqueous film forming foams (AFFFs) at military airports is a potential source of perfluoroalkyl acids (PFAAs) to the nearby environment. In this study, the distribution of perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorohexane sulfonate (PFHxS) and perfluorooctane sulfonate (PFOS) in soil, groundwater, surface water, tap water well, and fish muscle was investigated at a closed down military airfield (F18) and its surroundings in Stockholm, Sweden. The presence of PFOS at AFFF training sites was inventoried.One major finding of the study is that a former airfield, abandoned since 1994, may still be a point source of PFAAs to nearby recipients. PFOS and PFOA were ubiquitous in the soil samples at former AFFF training sites with concentrations ranging from 2.18 to 8520nggâ1 dry weight and <0.12â287nggâ1 dry weight respectively. The sum of PFAAs in the groundwater and surface waters ranged from 738 to 51000ngLâ1 and <MDL to 79.0ngLâ1, respectively. PFOS in European perch ranged from 76.5 to 370nggâ1wet weight muscle tissue which is among the highest previously reported worldwide. Our results provide evidence that the historical use of AFFF at the site have contaminated an aquifer (7500 m3dâ1), that will require constant PFAA purification before being used for drinking water production. Despite the fact that the water turnover time in the investigated recipients (of 4â6months) suggest a depletion of PFAA-contaminants over a quarter of a decade, abandoned airfields may still pose an environmental and human health concern.<br />
Keywords	Perca fluviatilis ; airports ; aquifers ; case studies ; fish ; foams ; groundwater ; human health ; lakes ; muscle tissues ; muscles ; soil ; soil sampling ; surface water ; tap water ; Sweden
Language	English
Dates of publication	2015-06
Size	p. 39-45.
Publishing place	Elsevier Ltd
Document type	Article
ZDB-ID	120089-6
ISSN	1879-1298 ; 0045-6535 ; 0366-7111
ISSN (online)	1879-1298
ISSN	0045-6535 ; 0366-7111
DOI	10.1016/j.chemosphere.2014.09.005
Database	NAL-Catalogue (AGRICOLA)

In stock of ZB MED Cologne/Königswinter

Zs.A 2540: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (2.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article: May Measurement Month 2018: an analysis of blood pressure screening results in South Africa.

Woodiwiss, Angela J / Kruger, Ruan / Norton, Gavin R / Schutte, Aletta E / Myburgh, Caitlynd / Nkeh-Chungag, Benedicta / Sewani-Rusike, Constance R / Vally, Muhammed / Jones, Erika / Peterson, Vernice / Marsh, Justin / Gafane-Matemane, Lebo F / Ahiante, Blessing O / Phalane, Edith / Beaney, Thomas / Chis Ster, Anca / Xia, Xin / Poulter, Neil R

European heart journal supplements : journal of the European Society of Cardiology

2020 Volume 22, Issue Suppl H, Page(s) H115–H118

Abstract: Elevated blood pressure (BP) is a growing burden worldwide, leading to over 10 million deaths each year. May Measurement Month (MMM) is a global initiative of the International Society of Hypertension (ISH) aimed at raising awareness of high BP and ... ...

Abstract	Elevated blood pressure (BP) is a growing burden worldwide, leading to over 10 million deaths each year. May Measurement Month (MMM) is a global initiative of the International Society of Hypertension (ISH) aimed at raising awareness of high BP and acting as a temporary solution to the lack of screening programmes worldwide. As part of MMM, screening in South Africa in 2017 revealed that 24.5% of adults (mean age = 31 years) have hypertension and only half of those with hypertension had controlled BP. These data highlight the need for continued screening and awareness campaigns. An opportunistic cross-sectional survey of volunteers aged ≥18 years was carried out in May 2018. Blood pressure measurements, the definition of hypertension and statistical analyses followed the MMM protocol. The sites screened were general populations and university campuses in preference to hospitals and clinics, aiming to raise awareness and allow access to screening to those less likely to be aware of their BP. In total, 2965 individuals (age 40.5 ± 18.2 years) were screened. After multiple imputation for missing BP readings, 34.6% had hypertension, only 56.7% of those with hypertension were aware, 21.2% of those not receiving treatment for hypertension were hypertensive, and a large proportion (42.5%) of individuals receiving antihypertensive medication had uncontrolled BP. These results suggest that opportunistic screening campaigns can identify significant numbers with undiagnosed and uncontrolled hypertension. The high proportions of individuals with undiagnosed and treated uncontrolled hypertension highlight the need for hypertension awareness campaigns and more rigorous management of hypertension.
Language	English
Publishing date	2020-08-28
Publishing country	England
Document type	Journal Article
ZDB-ID	1463769-8
ISSN	1554-2815 ; 1520-765X
ISSN (online)	1554-2815
ISSN	1520-765X
DOI	10.1093/eurheartj/suaa043
Database	MEDical Literature Analysis and Retrieval System OnLINE

In stock of ZB MED Cologne/Königswinter

Zs.A 1563 -Suppl.-: Show issues

Location:
Je nach Verfügbarkeit (siehe Angabe bei Bestand)
bis Jg. 1994: Bestellungen von Artikeln über das Online-Bestellformular
Jg. 1995 - 2021: Lesesall (1.OG)
ab Jg. 2022: Lesesaal (EG)

Order via subito

Details ▾
- See ZB MED holdings
- Order with fees

Article: Ultra-deep sequencing of foraminiferal microbarcodes unveils hidden richness of early monothalamous lineages in deep-sea sediments

Lecroq, BÃ©atrice / Lejzerowicz, Franck / Bachar, Dipankar / Christen, Richard / Esling, Philippe / Baerlocher, LoÃ¯c / ÃsterÃ¥s, Magne / Farinelli, Laurent / Pawlowski, Jan

Proceedings of the National Academy of Sciences of the United States of America. 2011 Aug. 9, v. 108, no. 32

2011

Abstract: Deep-sea floors represent one of the largest and most complex ecosystems on Earth but remain essentially unexplored. The vastness and remoteness of this ecosystem make deep-sea sampling difficult, hampering traditional taxonomic observations and ... ...

Abstract	Deep-sea floors represent one of the largest and most complex ecosystems on Earth but remain essentially unexplored. The vastness and remoteness of this ecosystem make deep-sea sampling difficult, hampering traditional taxonomic observations and diversity assessment. This problem is particularly true in the case of the deep-sea meiofauna, which largely comprises small-sized, fragile, and difficult-to-identify metazoans and protists. Here, we introduce an ultra-deep sequencing-based metagenetic approach to examine the richness of benthic foraminifera, a principal component of deep-sea meiofauna. We used Illumina sequencing technology to assess foraminiferal richness in 31 unsieved deep-sea sediment samples from five distinct oceanic regions. We sequenced an extremely short fragment (36 bases) of the small subunit ribosomal DNA hypervariable region 37f, which has been shown to accurately distinguish foraminiferal species. In total, we obtained 495,978 unique sequences that were grouped into 1,643 operational taxonomic units, of which about half (841) could be reliably assigned to foraminifera. The vast majority of the operational taxonomic units (nearly 90%) were either assigned to early (ancient) lineages of soft-walled, single-chambered (monothalamous) foraminifera or remained undetermined and yet possibly belong to unknown early lineages. Contrasting with the classical view of multichambered taxa dominating foraminiferal assemblages, our work reflects an unexpected diversity of monothalamous lineages that are as yet unknown using conventional micropaleontological observations. Although we can only speculate about their morphology, the immense richness of deep-sea phylotypes revealed by this study suggests that ultra-deep sequencing can improve understanding of deep-sea benthic diversity considered until now as unknowable based on a traditional taxonomic approach.
Keywords	Animalia ; ecosystems ; marine sediments ; phylotype ; protists ; ribosomal DNA
Language	English
Dates of publication	2011-0809
Size	p. 13177-13182.
Publishing place	National Academy of Sciences
Document type	Article
ZDB-ID	209104-5
ISSN	1091-6490 ; 0027-8424
ISSN (online)	1091-6490
ISSN	0027-8424
DOI	10.1073/pnas.1018426108
Database	NAL-Catalogue (AGRICOLA)

In stock of ZB MED Bonn / Germany

Z 4' 63/44: Show issues
87/25270: Show issues
Qa 4' 169/3: Show issues
Z 8.7: Show issues

Order via subito

Inter-library loan at ZB MED

Your chosen title can be delivered directly to ZB MED Cologne location if you are registered as a user at ZB MED Cologne.

Details ▾
- See ZB MED holdings
- Order with fees

To top

More links

Kategorien

Order via subito

More links

Kategorien

Order via subito

More links

Kategorien

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

Full text online

More links

Kategorien

Inter-library loan at ZB MED

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

In stock of ZB MED Cologne/Königswinter

Order via subito

More links

Kategorien

In stock of ZB MED Bonn / Germany

Order via subito

Inter-library loan at ZB MED