Dianion diagnostics in DESIREE: High-sensitivity detection of Cn2−\text{C}_{n}^{2-} from a sputter ion source

A sputter ion source with a solid graphite target has been used to produce dianions with a focus on carbon cluster dianions, $\text{C}_{n}^{2-}$, with $n=7-24$. Singly and doubly charged anions from the source were accelerated together to kinetic energies of 10 keV per atomic unit of charge and injected into one of the cryogenic (13 K) ion-beam storage rings of the Double ElectroStatic Ion Ring Experiment facility at Stockholm University. Spontaneous decay of internally hot $\text{C}_{n}^{2-}$ dianions injected into the ring yielded $\text{C}^{-}$ anions with kinetic energies of 20 keV, which were counted with a microchannel plate detector. Mass spectra produced by scanning the magnetic field of a $90^{\circ}$ analyzing magnet on the ion injection line reflect the production of internally hot $\text{C}_{7}^{2-}-\text{C}_{24}^{2-}$ dianions with lifetimes in the range of tens of microseconds to milliseconds. In spite of the high sensitivity of this method, no conclusive evidence of $\text{C}_{6}^{2-}$ was found while there was a clear $\text{C}_{7}^{2-}$ signal with the expect isotopic distribution. An upper limit is deduced for a $\text{C}_{6}^{2-}$ signal that is two orders-of-magnitue smaller than that for $\text{C}_{7}^{2-}$. In addition, $\text{C}_{n}\text{O}^{2-}$ and $\text{CsCu}^{2-}$ dianions were detected.Comment: 6 pages, 6 figure

Climate impact optimization in concrete bridge construction

Estimates indicate that the total climate impact, from a lifecycle perspective, generated bySwedish construction processes reaches the same magnitude as emissions from all passenger carsin Sweden. A large part of the emissions from construction of roads and railways arise fromproduction of steel and concrete used in bridges and other infrastructure structures. In thisresearch, several cases of existing concrete bridges have been investigated. The case studies are ina very firm way analyzed, and then opportunities for reducing climate gas emissions are describedand elaborated upon. Accordingly, design and dimensioning through the use of today’s technologyand material selection are discussed. Without developing new ways to construct bridges, orcomparing concrete with other materials, a useful guide on how to use technology andopportunities that are available for constructing climate smarter versions of standard bridgestoday is developed and described

Evidence of Wave-Particle Duality for Single Fast Hydrogen Atoms

We report the direct observation of interference effects in a Young\u27s double-slit experiment where the interfering waves are two spatially separated components of the de Broglie wave of single 1.3 MeV hydrogen atoms formed close to either target nucleus in H++H2 electron-transfer collisions. Quantum interference strongly influences the results even though the hydrogen atoms have a de Broglie wavelength, λdB, as small as 25 fm

Reducing uncertainty in health-care resource allocation

A key task for health policymakers is to optimise the outcome of health care interventions. The pricing of a new generation of cancer drugs, in combination with limited health care resources, has highlighted the need for improved methodology to estimate outcomes of different treatment options. Here we introduce new general methodology, which for the first time employs continuous hazard functions for analysis of survival data. Access to continuous hazard functions allows more precise estimations of survival outcomes for different treatment options. We illustrate the methodology by calculating outcomes for adjuvant treatment of gastrointestinal stromal tumours with imatinib mesylate, which selectively inhibits the activity of a cancer-causing enzyme and is a hallmark representative for the new generation of cancer drugs. The calculations reveal that optimal drug pricing can generate all win situations that improve drug availability to patients, make the most of public expenditure on drugs and increase pharmaceutical company gross profits. The use of continuous hazard functions for analysis of survival data may reduce uncertainty in health care resource allocation, and the methodology can be used for drug price negotiations and to investigate health care intervention thresholds. Health policy makers, pharmaceutical industry, reimbursement authorities and insurance companies, as well as clinicians and patient organisations, should find the methodology useful

Development and Validation of a Novel Risk Score for In-Hospital Major Bleeding in Acute Myocardial Infarction:-The SWEDEHEART Score

Background: Bleeding risk stratification in acute coronary syndrome is of highest clinical interest but current risk scores have limitations. We sought to develop and validate a new in‐hospital bleeding risk score for patients with acute myocardial infarction. Methods and Results: From the nationwide SWEDEHEART (Swedish Web‐System for Enhancement and Development of Evidence‐Based Care in Heart Disease Evaluated According to Recommended Therapies) register, 97,597 patients with acute myocardial infarction enrolled from 2009 until 2014 were selected. A full model with 23 predictor variables and 8 interaction terms was fitted using logistic regression. The full model was approximated by a model with 5 predictors and 1 interaction term. Calibration, discrimination, and clinical utility was evaluated and compared with the ACTION (Acute Coronary Treatment and Intervention Outcomes Network) and CRUSADE (Can Rapid Risk Stratification of Unstable Angina Patients Suppress Adverse Outcomes With Early Implementation of the ACC/AHA Guidelines) scores. Internal and temporal validity was assessed. In‐hospital major bleeding, defined as fatal, intracranial, or requiring surgery or blood transfusion, occurred in 1356 patients (1.4%). The 5 predictors in the approximate model that constituted the SWEDEHEART score were hemoglobin, age, sex, creatinine, and C‐reactive protein. The ACTION and CRUSADE scores were poorly calibrated in the derivation cohort and therefore were recalibrated. The SWEDEHEART score showed higher discriminative ability than both recalibrated scores, overall (C‐index 0.80 versus 0.73/0.72) and in all predefined subgroups. Decision curve analysis demonstrated consistently positive and higher net benefit for the SWEDEHEART score compared with both recalibrated scores across all clinically relevant decision thresholds. The original ACTION and CRUSADE scores showed negative net benefit. Conclusions: The 5‐item SWEDEHEART score discriminates in‐hospital major bleeding in patients with acute myocardial infarction and has superior model performance compared with the recalibrated ACTION and CRUSADE scores

Lifetimes of excited states in P-, As- and Sb-

Radiative lifetimes of three elements of the nitrogen group have been experimentally investigated at the Double ElectroStatic Ion Ring Experiment (DESIREE) facility at Stockholm University. The experiments were performed through selective laser photodetachment of excited states of P$^-$, As$^-$ and Sb$^-$ ions stored in a cryogenic storage ring. The experimental results were compared with theoretically predicted lifetimes, yielding a mixture of very good agreements in some cases and large discrepancies in others. These results are part of our efforts to map out the lifetimes of all excited states in negative ions. This data can be used to benchmark atomic theories, in particularly with respect to the degree of electron correlation that is incorporated in various theoretical models

The disruptive positions in human G-quadruplex motifs are less polymorphic and more conserved than their neutral counterparts

Specific guanine-rich sequence motifs in the human genome have considerable potential to form four-stranded structures known as G-quadruplexes or G4 DNA. The enrichment of these motifs in key chromosomal regions has suggested a functional role for the G-quadruplex structure in genomic regulation. In this work, we have examined the spectrum of nucleotide substitutions in G4 motifs, and related this spectrum to G4 prevalence. Data collected from the large repository of human SNPs indicates that the core feature of G-quadruplex motifs, 5′-GGG-3′, exhibits specific mutational patterns that preserve the potential for G4 formation. In particular, we find a genome-wide pattern in which sites that disrupt the guanine triplets are more conserved and less polymorphic than their neutral counterparts. This also holds when considering non-CpG sites only. However, the low level of polymorphisms in guanine tracts is not only confined to G4 motifs. A complete mapping of DNA three-mers at guanine polymorphisms indicated that short guanine tracts are the most under-represented sequence context at polymorphic sites. Furthermore, we provide evidence for a strand bias upstream of human genes. Here, a significantly lower rate of G4-disruptive SNPs on the non-template strand supports a higher relative influence of G4 formation on this strand during transcription