Publication Bias in Meta-Analysis: Confidence Intervals for Rosenthal's Fail-Safe Number

The purpose of the present paper is to assess the efficacy of confidence intervals for Rosenthal's fail-safe number. Although Rosenthal's estimator is highly used by researchers, its statistical properties are largely unexplored. First of all, we developed statistical theory which allowed us to produce confidence intervals for Rosenthal's fail-safe number. This was produced by discerning whether the number of studies analysed in a meta-analysis is fixed or random. Each case produces different variance estimators. For a given number of studies and a given distribution, we provided five variance estimators. Confidence intervals are examined with a normal approximation and a nonparametric bootstrap. The accuracy of the different confidence interval estimates was then tested by methods of simulation under different distributional assumptions. The half normal distribution variance estimator has the best probability coverage. Finally, we provide a table of lower confidence intervals for Rosenthal's estimator

Exploring the distribution for the estimator of Rosenthal's "fail-safe' number of unpublished studies in meta-analysis

The present article discusses the statistical distribution for the estimator of Rosenthal's ‘file-drawer’ number NR, which is an estimator of unpublished studies in meta-analysis. We calculate the probability distribution function of NR. This is achieved based on the central limit theorem and the proposition that certain components of the estimator NR follow a half-normal distribution, derived from the standard normal distribution. Our proposed distributions are supported by simulations and investigation of convergence

Photonic Physical Unclonable Functions: From the Concept to Fully Functional Device Operating in the Field

The scope of this paper is to demonstrate a fully working and compact photonic Physical Unclonable Function (PUF) device capable of operating in real life scenarios as an authentication mechanism and random number generator. For this purpose, an extensive experimental investigation of a Polymer Optical Fiber (POF) and a diffuser as PUF tokens is performed and the most significant properties are evaluated using the proper mathematical tools. Two different software algorithms, the Random Binary Method (RBM) and Singular Value Decomposition (SVD), were tested for optimized key extraction and error correction codes have been incorporated for enhancing key reproducibility. By taking into consideration the limitations and overall performance derived by the experimental evaluation of the system, the designing details towards the implementation of a miniaturized, energy efficient and low-cost device are extensively discussed. The performance of the final device is thoroughly evaluated, demonstrating a long-term stability of 1 week, an operating temperature range of 50C, an exponentially large pool of unique Challenge-Response Pairs (CRPs), recovery after power failure and capability of generating NIST compliant true random numbers

Mapping regional vulnerability in Europe’s energy transition: development and application of an indicator to assess declining employment in four carbon-intensive industries

Europe’s transition to an energy system compatible with limiting global heating to 1.5 °C will require radical changes in energy systems. While this will create substantial new growth industries in clean technologies, some currently important economic activities will decline. The impacts of that transition will not be the same for all regions. We map the economic vulnerability of European regions to ambitious decarbonisation scenarios in terms of employment losses in four carbon-intensive industries. To do so, we develop a composite vulnerability indicator that combines each region’s share of employment in those high-carbon industries with other dimensions of vulnerability and resilience. We then explore how regional patterns of vulnerability are influenced by the technology pathway to 2050, using four scenarios modelled using the European PRIMES model. We show that economic vulnerability to the low-carbon transition is regionally concentrated, with some regions combining high employment shares in industries expected to decline with weak adaptive capacity and high pre-existing unemployment. We also show that there is little variation in regional vulnerability arising from different transition pathways. All scenarios compatible with 1.5 °C involve large declines in all high-carbon sectors we analyse, and as a result, scenario variation does not lead to large variation in relative vulnerability of regions. The results highlight regions that may be in need of additional policy support to diversify their economies and achieve a just transition

Severe eosinophilic colitis caused by neuropathic agents in a patient with chronic fatigue syndrome and functional abdominal pain: case report and review of the literature

Eosinophilic colitis is a rare clinical condition that belongs to the group of eosinophilic gastrointestinal disorders. Its occurrence can be primary or secondary to infection, medications, or autoimmune/hematological conditions. We present a case of a young female adult with severe chronic fatigue syndrome, widespread chronic pain, including functional abdominal pain, who developed severe eosinophilic colitis following successive treatments with gabapentin and pregabalin. On both occasions, symptoms manifested as abdominal pain, diarrhea, and eosinophilia and improved upon discontinuation of the medications. Magnetic resonance imaging of the small bowel demonstrated an ascending colon colitis, and endoscopic investigations confirmed florid colitis mainly in the ascending colon with biopsies demonstrating a dense eosinophilic infiltrate with micro-abscesses. Serum eosinophil counts correlated well with the timing of the agents’ administration. There was no other organ involvement. Symptoms improved upon discontinuation of the drugs and steroid administration. Eosinophilic colitis is an exceptionally rare entity and its mechanism of action is still unclear. Suspicion of eosinophilic colitis should be raised if a patient presents with abdominal pain, diarrhea, and peripheral eosinophilia following treatment with pregabalin or gabapentin. / Die eosinophile Kolitis ist eine sehr seltene Krankheit aus der Gruppe der eosinophilen Magen-Darm-Erkrankungen. Als Auslöser gelten Primär- und Sekundärinfektionen, Medikamente, sowie autoimmune und hämatologische Erkrankungen. Unser Fall beschreibt eine junge, weibliche Erwachsene mit schwerem chronischem Müdigkeitssyndrom und generalisierten chronischen Schmerzen, darunter funktionellen Unterleibsschmerzen, welche unter Behandlung mit Gabapentin und Pregabalin an einer schweren eosinophilen Kolitis erkrankte. Zu zwei unterschiedlichen Zeitpunkten wies die Patientin abdominelle Schmerzen, Diarrhoe und ein Eosinophilie auf, mit jeweils Verbesserung der Symptomatik nach Sistieren der Medikamenteneinnahme. In einer Kernspintomografie stellte sich eine Kolitis des aufsteigenden Kolons dar. Endoskopisch konnte eine floride Kolitis, vorwiegend im Kolon ascendens, bestätigt werden, mit Nachweis einer dichten eosinophilen Infiltration mit Mikroabszessen in den Biopsien. Die serologische Eosinophilie korrelierte zeitlich mit der Medikamenteneinnahme. Andere Organe waren nicht beteiligt. Die Symptomatik verbesserte sich nach Absetzen der Medikamente und Verabreichung von Steroiden. Die eosinophile Kolitis ist eine ausgesprochen seltene Erkrankung mit bisher noch unklarem Wirkmechanismus. Bei Patienten mit abdominellen Schmerzen, Diarrhoe und peripherer Eosinophilie unter einer Therapie mit Pregabalin oder Gabapentin sollte der Verdacht auf eine eosinophile Kolitis gestellt werden

Perceived acceptability of partial enteral nutrition (PEN) using oral nutritional supplement drinks in adolescent and adult Crohn’s Disease outpatients: a feasibility study

BACKGROUND AND AIMS: Studies, mainly in Japanese cohorts, have shown that partial enteral nutrition (PEN) including oral nutritional supplement (ONS) drinks can prolong disease remission and increase drug effectiveness in Crohn’s disease (CD). Acceptability is a key feasibility parameter to determine whether PEN is a viable treatment option in UK CD patients. We report the results of a single centre cross-sectional feasibility study carried out to investigate perceived acceptability of PEN using ONS drinks and whether ONS preference varies with sex, nutritional status or phenylthiocarbamide (PTC) sensitivity. METHODS: Patients with a confirmed CD diagnosis were recruited using convenience sampling from an adult and adolescent gastroenterology outpatient clinic over 3 years. Blind taste testing of 5 polymeric ONS drinks was conducted using a validated 9-point hedonic rating scale followed by completion of the acceptability questionnaire based on the preferred ONS drink. A subset of patients took home the preferred ONS for a 7-day study. RESULTS: 105 CD patients (55 males), aged 34.9 (±15.4) years were recruited and 28 patients completed the 7-day ONS study. Overall impression scores did not significantly vary with nutritional status, sex, BMI, handgrip strength (HGS), mid-upper arm circumference (MUAC) or PTC sensitivity. Ensure plus™ milkshake rated highest for overall impression (6.5, p=<0.0001) and all other organoleptic properties (p<0.0001). The main perceived benefits of using ONS drinks as PEN related to assurance of nutrient intake (89.3%), convenience (85.7%), and improvement of gut symptoms (84.6%). The main perceived barriers related to reduction in pleasure from eating and drinking (55.6%), struggle with drink storage (53.6%) and increased tiredness than if eating 3 solid meals daily (52%%). 64.8% of patients would consider using PEN as a maintenance treatment option. 81.0% of patients felt confident about consuming ONS drinks daily as PEN for three months but this dropped to 63.8% and 37.1% at 6 and 12 months, respectively. There was a significant drop in perceived ease of use as PEN after the 7-day ONS study (P=0.01). CONCLUSION: Use of ONS drinks as PEN have high perceived benefits and appear to be a feasible option for short-term use of 3-6 months in CD patients. However, confidence in long-term use of ONS drinks as PEN is low mainly due to the perceived social impact. Future studies should assess longer trial periods and volume of ONS drinks to increase the validity of these findings

Citrulline as a marker of intestinal function and absorption in clinical settings: A systematic review and meta-analysis

Background: Citrulline has been described as a marker of intestinal function or absorption but evidence varies according to clinical settings. Objective: The objective of this article is to examine the evidence of plasma citrulline as a marker of intestinal function and absorption in various clinical settings. Methods: Studies were examined for p values, means and standard deviations, correlation coefficients or other metrics depicting the association of citrulline with intestinal function. A random effects model was used to produce a pooled estimate. A hierarchical summary receiver operating curve model was fitted for diagnostic accuracy measures. Results: Citrulline levels are correlated strongly with small bowel length in short bowel syndrome patients (r = 0.67). Citrulline is strongly negatively correlated (r = –0.56) with intestinal disease severity with regards to enteropathies (coeliac disease, tropical enteropathy, Crohn’s disease, mucositis, acute rejection in intestinal transplantation). Citrulline cut-off levels have an overall sensitivity and specificity of 80% and 84% respectively. Citrulline levels in untreated coeliac patients compared to controls were reduced by 10 µmol/l. Citrulline levels increase with gluten-free diet and with improvement of enteropathy. Citrulline is decreased in critical illness and sepsis. Conclusion: These findings allow us to advocate quite reasonably that citrulline is a marker of acute and chronic intestinal insufficiency

Fossil extraction bans and carbon taxes: Assessing their interplay through multiple models

Given concerns about the ambition and effectiveness of current climate policies, a case has been made for the combination of demand side policies such as carbon pricing with supply side bans on fossil fuel extraction. However, little is known about their interplay in the context of climate stabilization strategies. Here, we present a multi-model assessment quantifying the effectiveness of supply side policies and their interactions with demand-side ones. We explore a variety of fossil fuel bans with four integrated assessment models and find that international supply side policies reduce carbon emissions but not at sufficient levels to stabilize temperature increase to well below 2°C. When combined with demand side policies, supply side policies reduce the required carbon price, dampen reliance on CO2 removal technologies, and increase investment in renewable energy. The results indicate the opportunity to integrate fossil fuel bans alongside price-based policies when exploring pathways to reach ambitious mitigation targets

Temperature dependence of the Brewer global UV measurements

Spectral measurements of global UV irradiance recorded by Brewer spectrophotometers can be significantly affected by instrument-specific optical and mechanical features. Thus, proper corrections are needed in order to reduce the associated uncertainties to within acceptable levels. The present study aims to contribute to the reduction of uncertainties originating from changes in the Brewer internal temperature, which affect the performance of the optical and electronic parts, and subsequently the response of the instrument. Until now, measurements of the irradiance from various types of lamps at different temperatures have been used to characterize the instruments' temperature dependence. The use of 50 W lamps was found to induce errors in the characterization due to changes in the transmissivity of the Teflon diffuser as it warms up by the heat of the lamp. In contrast, the use of 200 or 1000 W lamps is considered more appropriate because they are positioned at longer distances from the diffuser so that warming is negligible. Temperature gradients inside the instrument can cause mechanical stresses which can affect the instrument's optical characteristics. Therefore, during the temperature-dependence characterization procedure warming or cooling must be slow enough to minimize these effects. In this study, results of the temperature characterization of eight different Brewer spectrophotometers operating in Greece, Finland, Germany and Spain are presented. It was found that the instruments' response changes differently in different temperature regions due to different responses of the diffusers' transmittance. The temperature correction factors derived for the Brewer spectrophotometers operating at Thessaloniki, Greece, and Sodankylä, Finland, were evaluated and were found to remove the temperature dependence of the instruments' sensitivity.This article is based upon work from COST Action ES1207 “A European Brewer Network (EUBREWNET)”, supported by COST (European Cooperation in Science and Technology) and from the ENV59-ATMOZ (“Traceability for atmospheric total column ozone”) Joint Research Programme (JRP)