bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bayes Lines Tool (BLT): a SQL-script for analyzing diagnostic test results with an application to SARS-CoV-2-testing
Authors: Aukema Wouter , Malhotra Bobby Rajesh , Goddek Simon , Kämmerer Ulrike , Borger Peter , McKernan Kevin , Klement Rainer Johannes 
Published: May 2021

The performance of diagnostic tests crucially depends on the disease prevalence, test sensitivity, and test specificity. However, these quantities are often not well known when tests are performed outside defined routine lab procedures which make the rating of the test results somewhat problematic. A current example is the mass testing taking place within the context of the world-wide SARS-CoV-2 crisis. Here, for the first time in history, laboratory test results have a dramatic impact on political decisions. Therefore, transparent, comprehensible, and reliable data is mandatory. It is in the nature of wet lab tests that their quality and outcome are influenced by multiple factors reducing their performance by handling procedures, underlying test protocols, and analytical reagents. These limitations in sensitivity and specificity have to be taken into account when calculating the real test results. As a resolution method, we have developed a Bayesian calculator, the Bayes Lines Tool (BLT), for analyzing disease prevalence, test sensitivity, test specificity, and, therefore, true positive, false positive, true negative, and false negative numbers from official test outcome reports. The calculator performs a simple SQL (Structured Query Language) query and can easily be implemented on any system supporting SQL. We provide an example of influenza test results from California, USA, as well as two examples of SARS-CoV-2 test results from official government reports from The Netherlands and Germany-Bavaria, to illustrate the possible parameter space of prevalence, sensitivity, and specificity consistent with the observed data. Finally, we discuss this tool’s multiple applications, including its putative importance for informing policy decisions.
COVID-19 lockdown and lifestyles: A narrative review
Authors: Doraiswamy Sathyanarayanan , Cheema Sohaila , Al Mulla Ahmad , Mamtani Ravinder 
Published: May 2021

Background: The primary objective worldwide during the coronavirus disease 2019 (COVID-19) pandemic has been controlling disease transmission. However, lockdown measures used to mitigate transmission have affected human behavior and altered lifestyles, with a likely impact on chronic non-communicable diseases. More than a year into the pandemic, substantial peer-reviewed literature has emerged on altered lifestyles following the varying lockdown measures imposed globally to control the virus spread. We explored the impact of lockdown measures on six lifestyle factors, namely diet, physical activity, sleep, stress, social connectedness, and the use of tobacco, alcohol, or other harmful substances. Methods: We comprehensively searched PubMed and the World Health Organization’s global literature database on COVID-19 and retrieved 649 relevant articles for the narrative review. A critical interpretative synthesis of the articles was performed. Results: Most of the articles included in the review identified the negative effect of lockdown measures on each of the lifestyle factors in many parts of the world. Encouraging lifestyle trends were also highlighted in a few articles. Such trends can positively influence the outcome of lifestyle-related chronic diseases, such as obesity and diabetes. Conclusions: The COVID-19 pandemic provides an opportunity to better understand the negative impact of strict lockdown measures on lifestyles. At the same time, it helps us identify and initiate positive behavioral changes, which, if consolidated, could improve chronic disease outcomes. It is up to governments, communities, and healthcare/academic entities to derive benefit from lessons learned from the pandemic, with the ultimate objective of better educating and promoting healthy lifestyles among communities.
Primary care-based models of care for osteoarthritis: a scoping review protocol
Authors: Cunningham Joice , Doyle Frank , Ryan Jennifer M. , Clyne Barbara , Cadogan Cathal , Cottrell Elizabeth , Smith Susan M. , French Helen P. 
Published: May 2021

Background: The burden of osteoarthritis (OA) to individuals and health systems is substantial and is expected to increase due to population ageing and rising prevalence of obesity and multimorbidity. Primary care-based models of care (MoCs) are being increasingly developed in response to this growing burden. However, these MoCs have yet to be formally reviewed. A MoC can be defined as an ‘evidence-informed strategy, framework or pathway that outlines the optimal manner in which condition-specific care should be delivered to consumers within a local health system’. Objective: To identify and describe the available research regarding the extent, nature and characteristics of MoCs for OA that have been developed or evaluated in primary care. Methods: A scoping review will be conducted in accordance with the Arksey and O’Malley scoping review framework and the PRISMA-ScR guidelines. Systematic literature searches of MEDLINE, EMBASE, CINAHL, PsychINFO, Web of Science and LILACs will be conducted from 2010 to present, aligning with publication dates of recent clinical guidelines. A structured iterative search of grey literature will be conducted. Full-text original quantitative or mixed method studies which describe the development or evaluation of MoCs for OA in primary care will be considered. Data will be charted and synthesised and a narrative synthesis will be conducted. Conclusions: This scoping review will provide a broad overview regarding the extent, nature and characteristics of the available literature on primary care based MoCs for OA. Findings will be used to identify gaps in the current evidence to identify areas for future research.
Exploring perceived barriers and enablers to fidelity of training and delivery of an intervention to reduce imaging for low back pain: a qualitative interview study protocol
Authors: To Daphne , De Carvalho Diana , Pike Andrea , Etchegary Holly , Patey Andrea , Toomey Elaine , Hall Amanda 
Published: May 2021

Background: Diagnostic imaging has limited utility in the assessment and management of non-specific low back pain (LBP), but remains commonly used in clinical practice. Interventions have been designed to reduce non-indicated imaging for LBP; however, evidence of effectiveness has been variable. It is unclear whether intervention fidelity was adequately assessed in these interventions, which may have an impact on the interpretation of trial results. Within implementation research, intervention fidelity refers to the degree to which an intervention was delivered as intended and to the strategies used to monitor and enhance this process. Intervention fidelity covers five domains: design, training, delivery, receipt, and enactment. Objectives: The objectives of this study are to explore perceived barriers and enablers to fidelity of training and delivery of a proposed theory-informed intervention aimed at reducing non-indicated imaging for LBP by general practitioners (GPs) and chiropractors in Newfoundland and Labrador (NL), Canada. Methods: Semi-structured interviews will be conducted with GPs and chiropractors in NL to explore their views on barriers and enablers towards enhancing and/or assessing fidelity of training and delivery. Interviews will be audio-recorded, transcribed verbatim, and analysed with the Theoretical Domains Framework. Relevant domains related to perceived barriers and enablers will be identified by: the frequency of beliefs; the presence of conflicting beliefs; and the perceived strength of the impact a belief may have on the target behaviours. Discussion: Results of this study will aid in the development of a fidelity protocol for an upcoming cluster randomised controlled trial of a theory-informed intervention aimed at reducing non-indicated imaging for LBP. Our results may help to ensure that the proposed intervention will be delivered with good fidelity and that fidelity can be appropriately assessed.
A pilot of the feasibility and usefulness of an aged obese model for use in stroke research
Authors: Learoyd Annastazia E. , Calmus Ryan , Cunningham Chelsea N. , England Tim J. , Farr Tracy D. , Fone Kevin C.F. , Kendall David A. , O’Sullivan Saoirse E. , Trueman Rebecca C. 
Published: May 2021

Background: Animal models of stroke have been criticised as having poor predictive validity, lacking risk factors prevalent in an aging population. This pilot study examined the development of comorbidities in a combined aged and high-fat diet model, and then examined the feasibility of modelling stroke in such rats. Methods: Twelve-month old male Wistar-Han rats (n=15) were fed a 60% fat diet for 8 months during which monthly serial blood samples were taken to assess the development of metabolic syndrome and pro-inflammatory markers. Following this, to pilot the suitability of these rats for undergoing surgical models of stroke, they underwent 30min of middle cerebral artery occlusion (MCAO) alongside younger controls fed a standard diet (n=10). Survival, weight and functional outcome were monitored, and blood vessels and tissues collected for analysis. Results: A high fat diet in aged rats led to substantial obesity. These rats did not develop type 2 diabetes or hypertension. There was thickening of the thoracic arterial wall and vacuole formation in the liver; but of the cytokines examined changes were not seen. MCAO surgery and behavioural assessment was possible in this model (with some caveats discussed in manuscript). Conclusions: This study shows MCAO is possible in aged, obese rats. However, this model is not ideal for recapitulating the complex comorbidities commonly seen in stroke patients.
The consequences of adjustment, correction and selection in genome-wide association studies used for two-sample Mendelian randomization
Authors: Walker Venexia , Harrison Sean , Carter Alice , Gill Dipender , Tzoulaki Ioanna , Davies Neil 
Published: May 2021

Introduction: Genome-wide association studies (GWASs) often adjust for covariates, correct for medication use, or select on medication users. If these summary statistics are used in two-sample Mendelian randomization analyses, estimates may be biased. We used simulations to investigate how GWAS adjustment, correction and selection affects these estimates and performed an analysis in UK Biobank to provide an empirical example. Methods: We simulated six GWASs: no adjustment for a covariate, correction for medication use, or selection on medication users; adjustment only; selection only; correction only; both adjustment and selection; and both adjustment and correction. We then ran two-sample Mendelian randomization analyses using these GWASs to evaluate bias. We also performed equivalent GWASs using empirical data from 306,560 participants in UK Biobank with systolic blood pressure as the exposure and body mass index as the covariate and ran two-sample Mendelian randomization with coronary heart disease as the outcome. Results: The simulation showed that estimates from GWASs with selection can produce biased two-sample Mendelian randomization estimates. Yet, we observed relatively little difference between empirical estimates of the effect of systolic blood pressure on coronary artery disease across the six scenarios. Conclusions: Given the potential for bias from using GWASs with selection on Mendelian randomization estimates demonstrated in our simulation, careful consideration before using this approach is warranted. However, based on our empirical results, using adjusted, corrected or selected GWASs is unlikely to make a large difference to two-sample Mendelian randomization estimates in practice.
Natural Gas in Kansas
Authors: Merriam Daniel F. , Goebel Edwin D. 
Published: May 2021

Abstract
Natural gas production in Kansas has totaled about 11.4 trillion cu ft since commercial discovery in 1873 in Allen County. The large Hugoton gas area in the southwestern part of the state accounts for most of the production. Kansas gas reserves are estimated to be about 17.4 trillion cu ft.
Permian rocks have yielded about 74 per cent of the cumulative production, Pennsylvanian rocks 15 per cent, and Mississippian rocks 9 per cent; the other 2 per cent is from lower Paleozoic rocks. A very minor quantity of gas has been produced from Cretaceous rocks in northwestern Kansas.
Cumulative gas production reported from the major structural features of the state is Hugoton embayment, 76 per cent; Cherokee basin, 8 per cent; Sedgwick basin, 8 per cent; Central Kansas uplift, less than 3 per cent; Pratt anticline, less than 2 per cent; and the Forest City basin, Nemaha anticline, and Salina basin each less than 1 per cent.
Helium, natural gas liquids, and carbon black are important byproducts from the natural gas. Transport of the gas is by more than 12,000 mi of pipeline. About half of the amount of the annual production is consumed within the state.
Black Warrior Basin, Northeast Mississippi and Northwest Alabama
Authors: Pike Stuart J. 
Published: May 2021

Abstract
The Black Warrior basin of northeast Mississippi and northwest Alabama is a triangular area of 35,000 sq mi of Paleozoic strata bounded on the north by the Nashville and Ozark domes, on the southeast by the folded Appalachians, and the southwest by the buried Ouachita mountains. The western two-thirds of the basin is buried beneath Mesozoic and Tertiary strata of the Gulf Coastal Plain and Mississippi embayment.
The first gas production in the basin was established in 1909. Since that time exploration has been sporadic, but in the early 1950's seven Upper Mississippian gas fields and a one-well Ordovician oil field were discovered in the exploration program which followed the development of the Muldon gas field.
During most of Paleozoic time, the basin was part of the stable continental interior and received more than 17,000 ft of sediment typical of that deposited in the shallow inland seas of the era. The center of the basin shifted in each Paleozoic period. In Early Pennsylvanian time, there was a great downwarping of the basin accompanied by an uplift of orogenic belts on the southeast and probably on the southwest; more than 10,000 ft of Pottsville sediment was deposited in the Black Warrior trough. After Pennsylvanian time, the basin was uplifted and received no Permian sediment. In early Mesozoic time, the province was downwarped on the southwest and was covered with the Mesozoic and Tertiary sediment of the Mississippi embayment.
The Paleozoic strata of the basin are complexly faulted, and most of the gas fields are on faulted structural features which were located by geophysical methods. All of the gas production is from Upper Mississippian Chester sandstone beds which have a marked lack of lateral persistence and extreme lateral and vertical variations in porosity and permeability.
The eight-well Muldon field is the largest gas field in the basin, It is on a horst-like fault block, and production is from the Sanders sandstone, of middle Chester age, at a depth of 5,500 ft. Total recoverable reserve of the Muldon field is estimated to be 70 billion cu ft of gas.
Most of the Paleozoic rocks of the basin have abundant oil and gas shows where there is porosity. There are several unconformities in the basin which offer the possibility of large-scale stratigraphic traps, and there are many undrilled structural anomalies. It seems probable that much more oil and gas will be found in the basin in the future.
Natural Gas Industry In The United States
Authors: Davis Ralph E. 
Published: May 2021

Abstract
Since 1945, the competitive position of natural gas in the fossil-fuel energy market has improved; the position of oil has improved less markedly; and the position of coal has deteriorated substantially. In 15 years the natural gas industry has grown to the nation's fifth largest. The natural gas industry, however, has serious problems. It is composed of varied groups with diverse interests—consumers, representatives of state and federal regulatory agencies, distributors, pipeline transmission companies, and producers. Conditions and problems are so different among groups, and even within groups that are widely separated geographically, that the natural gas industry cannot speak with unity, and its position is thus weakened.
In 1964, natural gas and accompanying liquids (wet gas) supplied 33.5 per cent, crude oil and net imported products 40.3 per cent, coal 22.5 per cent, and water and nuclear power 3.7 per cent of the primary energy consumed in the United States. Although the primary-energy requirements in the United States increased about 60 per cent from 1945 to 1964, use of natural gas (wet) increased more than fourfold. During the same period, use of coal declined by two-thirds.
This large increase in the use of natural gas has led to the erroneous belief that continued growth at this rate can be expected for a decade or more; if this were to be so, by 1975 more than 25 trillion cu ft of natural gas would be required to supply the same percentage of the primary-energy demand. This belief has no justification in fact. Any seeming overabundance of natural gas is an illusion brought 'about by local conditions of supply and demand. To meet such ephemeral demands, it is not feasible to build facilities for gas that cannot be found and produced. There are many estimates of total supply with the widest range, and that of the writer is one of the more conservative. Estimated future supplies exist “on paper,” but are by no means assured. They must be found and developed in the face of increasingly difficult and costly exploration and competition from other fuels, principally coal. If the producers of primary energy cannot work together, the consequences may be detrimental to all.
Proved and Probable Reserves, Production Rates, and Availability of Natural Gas
Authors: Davis Ralph E. , Milton Wege J. , Falconer R. M. , Gimblet Ernest , Simmons James , Arrington Louis , Hopkins W. B. , Webb J. B. , White R. J. , Knight G. L. , Beebe B. W. 
Published: May 2021

Abstract
The estimation of proved and probable natural gas reserves must be based firmly not only on detailed knowledge of the engineering factors involved, but, generally even more important, on a thorough knowledge of the geology and potential for additional natural gas discovery. Different areas and even different producing formations within a single area have decidedly different characteristics for natural gas production rates, availability, and recovery. The rate at which a discrete gas reserve can be depleted is very important to pipelines.
As the competition for gas reserves increases, more and more lines are financed on the basis of sound estimates of proved reserves available and judgment with regard to supplies which can be expected reasonably to be developed in the area to be served by the pipeline. A study of the Homeglen-Rimbey field illustrates this important principle. In areas where exploration and development are unusually costly, reserves otherwise would not be developed in a timely fashion.
Important as estimates of proved and probable reserves are, even more important in many cases are studies of the availability of gas reserves—the rate at which they can be produced. A mathematically calculated 20-yr supply of natural gas which actually may require several times that length of time to produce is insufficient in times of peak requirements. There are several methods by which to determine volumes of gas available at any one period from a well, reservoir, pool, field, or even a system. Most of them require use of large numbers of data, and too commonly not all of the necessary data are available. Calculations are long, involved, and arduous. The Davis-Meltzer curve, which is simply a study of the production rate of several depleted or nearly depleted fields where geologic and reservoir conditions are similar, is a simple, reasonable means of determining availability within the accuracy normally required and obviates the laborious calculations of other methods. If likes are compared with likes, the method is superior to any other, but sound judgment in its application is mandatory.
Gas Reserves in Western Canada
Authors: Leslie Gordon A. 
Published: May 2021

Abstract
Primary exploration for natural gas in the Western Canada sedimentary basin may become as important as primary exploration for oil in the future, if justified by the market demand for natural gas and national gas products in Canada and the United States. Of the three western provinces, Alberta is in the most advanced stage of exploration with a drilling density of one wildcat well for every 29 sq mi of area favorable for gas and oil discovery. British Columbia is second in importance and Saskatchewan has neither large reserves nor potential large undiscovered supply. The Yukon and Northwest Territories are essentially unexplored.
Current exploration trends indicate that in the future carbonate reservoirs of the Triassic, Permian-Pennsylvanian, Mississippian, and Devonian will become increasingly predominant as sources of natural gas in comparison to the gas-producing sandstone beds of the Cretaceous, Jurassic, and Triassic.
Under favorable economic conditions, potential ultimate discovery of from 240 to 300 trillion cu ft of gas supply is anticipated in the Western Canada sedimentary basin, including the Yukon and Northwest Territories but exclusive of the Arctic Islands and the continental shelves.
Natural Gases of North America—A Summary
Authors: Beebe B. W. , Curtis Bruce F. 
Published: May 2021

Abstract
The purpose of this symposium is to assemble and critically examine the known facts regarding the origin, migration, accumulation, occurrence, exploration for, production of, and uses of natural gas and the many related factors which may affect them. The “geology” of natural gas is simply the geology of all petroleum, and the geology by which many mineral accumulations are controlled. The diverse substances constituting petroleum, both natural gas and crude oil, are formed and accumulate in the earth in regular patterns. The better the understanding of the conditions under which natural gas is found, the more effective will be the finding effort. This search is increasingly important because of the burgeoning requirements for natural gas.
The phenomenal growth of the requirements for and production of natural gas and liquids derived therefrom was the major postwar development in the domestic petroleum industry. Only a few years before, an operator who discovered natural gas in many parts of the country was a victim of a greater misfortune than one who drilled a dry hole. The discoverer of a gas well, not knowing much about the true relation between natural gas and oil, and assuming he had found a gas cap, commonly tried to “blow off” the gas so that oil could be produced. Hence, natural gas was wasted wantonly, not only in the circumstances described, but also, when produced with oil, by venting or flaring because of lack of market.