Quasigraphite: Density functional theory based predictions of a structure and its properties

Based on density-functional calculations, we propose a carbon-based nanostructure which we call quasigraphite phase. The quasigraphite phase resembles carbon nanotubes welded into planes, which are arranged similar to layers in graphite. It demonstrates a strong stability with respect to temperatures and external strain. The elastic and electronic properties of the proposed structure are discussed.Peer reviewe

Gone with the wind? An empirical analysis of the renewable energy rent transfer

Subsidies to renewable energy are costly and contentious. We estimate the reduction in prices that follows from the subsidized entry of wind power in the Nordic electricity market. A relatively small-scale entry of renewables leads to a large-scale transfer of surplus from the incumbent producers to the consumers: 10 % market share for wind generation eliminates one-half of the total electricity market expenditures. The subsidies generate net gains to consumers. We develop an approach to analyzing storage and renewable energy in equilibrium, and provide an anatomy of a market dominated by such technologies

Gone with the wind? An empirical analysis of the renewable energy rent transfer

Subsidies to renewable energy are costly and contentious. We estimate the reduction in prices that follows from the subsidized entry of wind power in the Nordic electricity market. A relatively small-scale entry of renewables leads to a large-scale transfer of surplus from the incumbent producers to the consumers: 10 % market share for wind generation eliminates one-half of the total electricity market expenditures. The subsidies generate net gains to consumers. We develop an approach to analyzing storage and renewable energy in equilibrium, and provide an anatomy of a market dominated by such technologies

Hydrogen interaction with fullerenes: From C[sub 20] to graphene

The paper presents a systematic study of the trends in the interaction of hydrogen with carbon fullerenes versus their curvature, where graphene is taken as the limit of zero curvature. The efficiency of hydrogen incapsulation in fullerenes, penetration into them, and adsorption on their surface are analyzed and discussed. The effects on magnetism are also considered; in particular, it is shown that hydrogen adsorption to some fullerenes induces magnetism to initially nonmagnetic systems. In addition, highly hydrogen-saturated fullerenes are examined and the suitability of fullerenes for hydrogen storage is discussed.Peer reviewe

Hydrogen transport on graphene: Competition of mobility and desorption

The results of molecular dynamics (MD) simulations of atomic hydrogen kinetics on graphene are presented. The simulations involve a combination of approaches based on Brenner carbon-hydrogen potential and first-principles force calculations. Both kinds of MD calculations predict very similar qualitative trends and reproduce equally well the features of hydrogen behavior, even such sophisticated modes as long correlated jump chains. Both approaches agree that chemisorbed hydrogen diffusion on graphene is strongly limited by thermal desorption. This limitation rules out long-range diffusion of hydrogen on graphene but does not exclude the short-range hydrogen diffusion contribution to hydrogen cluster nucleation and growth.Peer reviewe

Factors contributing to reported medication administration incidents in patients' homes - A text mining analysis

AIMS: To describe the characteristics of medication administration (MA) incidents reported to have occurred in patients' own homes (reporters' profession, incident types, contributing factors, patient consequence, and most common medications involved) and to identify the connection terms related to the most common contributing factors based on free text descriptions. DESIGN: A retrospective study using descriptive statistical analysis and text mining. METHODS: Medication administration incidents (N = 19,725) reported to have occurred in patients' homes between 2013-2018 in one district in Finland were analysed, describing the data by the reporters' occupation, incident type, contributing factors, and patient consequence. SAS® Text Miner was used to analyse free text descriptions of the MA incidents to understand contributing factors, using concept linking. RESULTS: Most MA incidents were reported by practical (lower level) nurses (77.8%, N = 15,349). The most common category of harm was 'mild harm' (40.1%, N = 7,915) and the most common error type was omissions of drug doses (47.4%, N = 9,343). The medications most commonly described were Marevan [warfarin] (N = 2,668), insulin (N = 811), Furesis [furosemide] (N = 590), antibiotic (N = 446), and Panadol [paracetamol] (N = 416). The contributing factors most commonly reported were 'communication and flow of information' (25.5%, N = 5,038), 'patient and relatives' (22.6%, N = 4,451), 'practices' (9.9%, N = 1,959), 'education and training' (4.8%, N = 949), and 'work environment and resources' (3.0%, N = 598). CONCLUSION: There is need for effective communication and clear responsibilities between home care patients and their relatives and health providers, about MA and its challenges in home environments. Knowledge and skills relating to safe MA are also essential. IMPACT: These findings about MA incidents that have occurred in patients' homes and have been reported by home care professionals demonstrate the need for medication safety improvement in home care

Factors Related to Medication Administration Incidents in England and Wales Between 2007 and 2016: A Retrospective Trend Analysis

OBJECTIVES The aims of the study were to describe medication administration incidents reported in England and Wales between 2007 and 2016, to identify which factors (reporting year, type of incident, patients' age) are most strongly related to reported severity of medication administration incidents, and to assess the extent to which relevant information was underreported or indeterminate. METHODS Medication administration incidents reported to the National Reporting & Learning System between January 1, 2007, and December 31, 2016 were obtained. Characteristics of the data were described using frequencies, and relationships between variables were explored using cross-tabulation. RESULTS A total of 517,384 incident reports were analyzed. Of these, 97.1% (n = 502,379) occurred in acute/general hospitals, mostly on wards (69.1%, n = 357,463), with medicine the most common specialty area (44.5%, n = 230,205). Medication errors were most commonly omitted doses (25.8%, n = 133,397). The majority did not cause patient harm (83.5%, n = 432,097). When only incidents causing severe harm or death (n = 1,116) were analyzed, the most common type of error was omitted doses (24.1%). Most incidents causing severe harm or death occurred in patients aged 56 years or older. For the 10-year period, the percentage of incidents with “no harm” increased (74.1% in 2007 to 86.3% in 2016). For some variables, data were often missing or indeterminate, which has implications for data analysis. CONCLUSIONS Medication administration incidents that do not cause harm are increasingly reported, whereas incidents reported as severe harm and death have declined. Data quality needs to be improved. Underreporting and indeterminate data, inaccuracies in reporting, and coding jeopardize the overall usefulness of these data

Structure and magnetic properties of adatoms on carbon nanotubes

We use ab initio methods to calculate the physical and electronic properties of carbon adatoms on different characteristic carbon nanotubes. We found that for every tube the energetically favored adsorption geometry is a “bridgelike” structure between two surface carbons, perpendicular to the long axis of the tube. For adsorption perpendicular or parallel to the axis, the calculations show that the adatom is spin polarized, although the magnitude of the magnetic moment depends mainly on the electronic structure of the nanotube itself.Peer reviewe

Medication administration errors and mortality: Incidents reported in England and Wales between 2007 ̶ 2016

Background Medication administration errors may contribute to patient mortality, thus additional understanding of such incidents is required. Objectives To analyse medication administration errors reported in acute care resulting in death, to identify the drugs concerned, and to describe medication administration error characteristics (location of error, error type, patient's age) by drug group. Methods Medication administration errors reported in acute care in 2007 ̶ 2016 (n = 517,384) were obtained from the National Reporting and Learning System for England and Wales. Incidents reported as resulting in death (n = 229) were analysed. Drugs were classified by two researchers using the British National Formulary. Drug categories were described by medication administration errors' year, location, patient age, and error category based on the incidents’ original classification. Results Errors were most often reported on wards (66.4%, n = 152), and in patients aged over 75 years (41.5%, n = 95). The most common error category was omitted medicine or ingredient (31.4%, n = 72); most common drug groups were cardiovascular (20.1%, n = 46) and nervous system (10.0%, n = 23). Most errors in patients under 12 years concerned drugs to treat infection; cardiovascular drugs were most common among other age groups. Conclusions In order to prevent these most serious of medication administration errors, interventions should focus on avoiding dose omissions, and administration of drugs for patients over 75 years old, as well as safe administration of parenteral anticoagulants and antibacterial drugs