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There is a concern that the COVID-19 pandemic will lead to an increase in suicides. Several reports from the first months of the pandemic showed no increase in suicide rates while studies with longer observation times report contrasting results. In this study, we explore the suicide rates in Norway during the first year of the pandemic for the total population as well as for relevant subgroups such as sex, age, geographical areas, and pandemic phases.
Methods
This is a cohort study covering the entire Norwegian population between 2010 and 2020. The main outcome was age-standardized suicide rates (per 100,000 inhabitants) in 2020 according to the Norwegian Cause of Death Registry. This was compared with 95% prediction intervals (95% PI) based on the suicide rates between 2010 and 2019.
Results
In 2020, there were 639 suicides in Norway corresponding to a rate of 12.1 per 100,000 (95% PI 10.2–14.4). There were no significant deviations from the predicted values for suicides in 2020 when analyzing age, sex, pandemic phase, or geographical area separately. We observed a trend toward a lower than predicted suicide rate among females (6.5, 95% PI 6.0–9.2), and during the two COVID-19 outbreak phases in 2020 (2.8, 95% PI 2.3–4.3 and 2.8, 95% CI 2.3–4.3).
Conclusion
There is no indication that the COVID-19 pandemic led to an increase in suicide rates in Norway in 2020.
It currently remains unclear in how far supratherapeutic lithium serum concentrations can affect the cardiac conduction system. Prolonged QT interval, arrhythmias and cardiac death have all been anecdotally reported, but the systematic studies are few.
Objectives
To examine ECG changes occurring with supratherapeutic lithium concentrations that have given rise to lithium toxicity.
Methods
We examined all episodes of lithium intoxication defined as serum lithium level (≥ 1.5 mmol/L). We analyzed ECG before, during and after intoxication and recorded ECG changes. These, we then assessed according to type of intoxications, clinical and other pharmacological characteristics. The study is based on 20-year data (1997-2020) from the retrospective cohort study (LiSIE) in the Swedish region of Norrbotten.
Results
Of 1101 patients treated with lithium, 77 patients had experienced lithium intoxications. 12 patients had more than one episode of intoxication, yielding 91 episodes. 39 had ECG available both as reference and during lithium intoxication. We found no statistically significant prolongation of the QTc interval during lithium intoxication, compared to respective reference ECG (p = 0.364). Heart rate during lithium intoxication was significantly lower, mean 73 beats/min (SD 16,8, range 43 - 112), compared to the reference ECG, mean 79 beats/min (SD 15,3, range 48-112; p = 0.006). No patient died. All findings were independent of whether an intoxication was acute or chronic.
Conclusions
In our study, heart rate was significantly lower during episodes of intoxication. However, this decrease was of no clinical relevance in most cases. Lithium intoxication was not associated with prolonged QT time.
Disclosure
M. Ott: scientific advisory board member of Astra Zeneca, Sweden. U. Werneke: received funding for educational activities on behalf of Norrbotten Region; Astra Zeneca, Eli Lilly, Janssen, Novartis, Otsuka/Lundbeck, Servier, Shire, Sunovion. Others: None
We have adapted the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) Science Pipelines to process data from the Gravitational-wave Optical Transient Observer (GOTO) prototype. In this paper, we describe how we used the LSST Science Pipelines to conduct forced photometry measurements on nightly GOTO data. By comparing the photometry measurements of sources taken on multiple nights, we find that the precision of our photometry is typically better than 20 mmag for sources brighter than 16 mag. We also compare our photometry measurements against colour-corrected Panoramic Survey Telescope and Rapid Response System photometry and find that the two agree to within 10 mmag (1$\sigma$) for bright (i.e., $\sim 14{\rm th} \mathrm{mag}$) sources to 200 mmag for faint (i.e., $\sim 18{\rm th} \mathrm{mag}$) sources. Additionally, we compare our results to those obtained by GOTO’s own in-house pipeline, gotophoto, and obtain similar results. Based on repeatability measurements, we measure a $5\sigma$L-band survey depth of between 19 and 20 magnitudes, depending on observing conditions. We assess, using repeated observations of non-varying standard Sloan Digital Sky Survey stars, the accuracy of our uncertainties, which we find are typically overestimated by roughly a factor of two for bright sources (i.e., $< 15{\rm th} \mathrm{mag}$), but slightly underestimated (by roughly a factor of 1.25) for fainter sources ($> 17{\rm th} \mathrm{mag}$). Finally, we present lightcurves for a selection of variable sources and compare them to those obtained with the Zwicky Transient Factory and GAIA. Despite the LSST Software Pipelines still undergoing active development, our results show that they are already delivering robust forced photometry measurements from GOTO data.
Experiments were initiated to characterize a waterhemp population (CHR) discovered in a central Illinois corn field after it was not controlled by the 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitor topramezone. Field experiments conducted during 2014–2015 indicated that acetolactate synthase (ALS)-, protoporphyrinogen oxidase (PPO)-, photosystem II (PSII)-, and HPPD-inhibiting herbicides and the synthetic auxin 2,4-D did not control the CHR population. Laboratory experiments confirmed target site–based resistance mechanisms to ALS- and PPO-inhibiting herbicides. Herbicide doses required to reduce dry biomass 50% (GR50) were determined in greenhouse dose–response experiments, and indicated 16-fold resistance to the HPPD inhibitor mesotrione, 9.5-fold resistance to the synthetic auxin 2,4-D, and 252-fold resistance to the PSII inhibitor atrazine. Complementary results from field, laboratory, and greenhouse investigations indicate that the CHR population has evolved resistance to herbicides from five sites of action (SOAs): ALS-, PPO-, PSII-, and HPPD-inhibiting herbicides and 2,4-D. Herbicide use history for the field in which CHR was discovered indicates no previous use of 2,4-D.
Impact craters are the dominant landform on Mercury and range from the largest basins to the smallest young craters. Peak-ring basins are especially prevalent on Mercury, although basins of all forms are far undersaturated, probably the result of the extensive volcanic emplacement of intercrater plains and younger smooth plains between about 4.1 and 3.5 Ga. This chapter describes the geology of the two largest well-preserved basins, Caloris and Rembrandt, and the three smaller Raditladi, Rachmaninoff, and Mozart basins. We describe analyses of crater size–frequency distributions and relate them to populations of asteroid impactors (Late Heavy Bombardment in early epochs and the near-Earth asteroid population observable today during most of Mercury’s history), to secondary cratering, and to exogenic and endogenic processes that degrade and erase craters. Secondary cratering is more important on Mercury than on other solar system bodies and shaped much of the surface on kilometer and smaller scales, compromising our ability to use craters for relative and absolute age-dating of smaller geological units. Failure to find “vulcanoids” and satellites of Mercury suggests that such bodies played a negligible role in cratering Mercury. We describe an absolute cratering chronology for Mercury’s geological evolution as well as its uncertainties.
Individuals born small have an increased risk for developing type 2 diabetes. Altered food preferences in these subjects seem to play a role; however, limited evidence is available on the association between being born small-for-gestational-age (SGA) at term and food intake in adolescence. Alterations in leptin, ghrelin and dopamine levels are suggested mechanisms linking SGA with later food intake. From a large prospective Danish National Birth Cohort, we compared dietary intake of adolescents being born SGA with normal-for-gestational-age (NGA) adolescents. Intake of foods and nutrients was assessed by a validated food frequency questionnaire in a subsample of 15,607 14-year-old individuals born at term. SGA was defined by birth weight (BW) <10th percentile (n = 1470) and NGA as BW between 10 and 90th percentile (n = 14,137) according to sex and gestational age-specific BW standard curves. Girls born SGA had a 7% (95% CI: 3–12%, P = 0.002) higher intake of added sugar and a 2–8% lower intake of dietary fibre, vegetables, polyunsaturated fatty acids, and total n−6, compared with NGA girls (P < 0.05). Adjusting for parental socio-occupational status, maternal smoking and diet in pregnancy did not substantially change the differences in dietary intake, except from dietary fibre, which were no longer statistically significant. No significant differences in dietary intake between SGA and NGA boys were found. In summary, girls born SGA had an unfavourable dietary intake compared with NGA girls. These differences persisted after controlling for potential confounders, thus supporting a fetal programming effect on dietary intake in girls born SGA at term. However, residual confounding by other factors operating early in childhood cannot be excluded.
To quantify and characterize overall antimicrobial use, including appropriateness of indication, among patients receiving chronic hemodialysis.
Design.
Retrospective and prospective observational study.
Setting.
Two outpatient hemodialysis units.
Patients.
All patients receiving chronic hemodialysis.
Methods.
The rate of parenteral antimicrobial use (number of doses per 100 patient-months) was calculated retrospectively from September 2008 through July 2011. Indication and appropriateness of antimicrobial doses were characterized prospectively from August 2010 through July 2011. Inappropriate administration was defined as occasions when criteria for infection based on national guidelines were not met, failure to choose a more narrow-spectrum antimicrobial on the basis of culture data, or occasions when indications for surgical prophylaxis were not met.
Results.
Over the 35-month retrospective study period, the rate of parenteral antimicrobial use was 32.9 doses per 100 patient-months. Vancomycin was the most commonly prescribed antimicrobial, followed by cefazolin and third- or fourth-generation cephalosporins. Over the 12-month prospective study, 1,003 antimicrobial doses were prescribed. Among the 926 (92.3%) doses for which an indication for administration was available, 276 (29.8%) were classified as inappropriate. Of these, a total of 146 (52.9%) did not meet criteria for infection, 74 (26.8%) represented failure to choose a more narrow-spectrum antimicrobial, and 56 (20.3%) did not meet criteria for surgical prophylaxis. The most common inappropriately prescribed antimicrobials were vancomycin and third- or fourth- generation cephalosporins.
Conclusions.
Parenteral antimicrobial use was extensive, and as much as one-third was categorized as inappropriate. The findings of this study provide novel information toward minimizing inappropriate antimicrobial use.
Self-assembled InAs quantum dot clusters (QDCs) and InGaAs QD molecules (QDMs) have been demonstrated through a growth technique called “droplet epitaxy” by molecular beam epitaxy (MBE). For QDCs, the size and density of QDs can be controlled with variation of InAs monolayer coverages. For QDMs, Ga contribution from GaAs mound with the interaction of InAs deposition resulted in various number of InGaAs QDs per GaAs mound, ranging from 2 to 6 (bi-QDMs to hexa-QDMs) depending on the specific InAs monolayer deposition. High step density on sidewall of GaAs mound and anisotropy of surface diffusion gave a rise to preferential formation of InAs and InGaAs QDs around GaAs mounds. This hybrid growth approach combining droplet epitaxy and typical QD growth is relatively simple and flexible and doesn't require further ex-situ surface preparation. This approach of QD arrangement can find applications in optoelectronics as well as physical study of QD interaction.
We study a generalization of the Svarc genus of a fibre map. For an arbitrary collection ɛ of spaces and a map f : X → Y, we define a numerical invariant, the ɛ-sectional category of f, in terms of open covers of Y. We obtain several basic properties of ɛ-sectional category, including those dealing with homotopy domination and homotopy pushouts. We then give three simple axioms which characterize the ɛ-sectional category. In the final section, we obtain inequalities for the ɛ-sectional category of a composition and inequalities relating the ɛ-sectional category to the Fadell–Husseini category of a map and the Clapp–Puppe category of a map.
We have compiled data from the literature on rotational velocities and/or periods for > 1000 K & M stars in 10 young clusters ranging in age from Orion to the IC 1391/2602. These data show that most PMS stars < 3 Myr do not appear to spin up in response to contraction, but there is a suggestion of slight spinup by ~8 Myr. These results extend and reinforce our earlier study (Rebull et al. 2002), based on observations of ~300 stars in the Orion Flanking Fields, NGC 2264, and the Orion Nebula Cluster (ONC), which showed that the majority of PMS stars in these three groups apparently do not conserve stellar angular momentum as they contract, but instead evolve at nearly constant angular velocity. This result applies both to stars with and without near-IR I – K excesses indicative of disks.
An important agenda power in parliamentary democracies is the discretion over the dissolution of parliament. We argue that variation in constitutional rules and the political environment will systematically affect the frequency of early elections. We hypothesize that dissolution will be more frequent under single-party governments, when the head of state plays an insignificant role, when neither parliament nor the cabinet can inhibit dissolution, when minority governments are in power, when the head of state can dissolve unilaterally, and later in the constitutional term. Using standard logistic and Cox-proportional hazard techniques, we test these expectations in a pooled time-series setting against observations of most OECD parliamentary democracies for the years 1960–1995. We find that parliamentary dissolutions are more frequent earlier in the constitutional term, under minority governments, when the head of state plays an insignificant role, and when the parliament or the cabinet is not involved.
In an effort to understand the effects of a quartenary element introduced into a ternary quasicrystalline system, quartenary Al71Pd21Mn8−XReX quasicrystals were grown, where X had values of 0, 0.08, 0.25, 0.4, 0.8, 2, 5, and 8. X-ray data confirm that the addition of a fourth element does not alter the quasiperiodicity of the sample. Because electronic transport is governed by different mechanisms in the parent systems (Al71Pd21Mn8 and Al71Pd21Re8), electrical and thermal transport measurements in the alloyed system have been performed on these samples and are presented here.
Quasicrystals have properties associated with both crystalline and amorphous materials. These properties appear to be sensitive to both composition and annealing conditions. Therefore, it is important to investigate the influence of the microstructure on the electrical and thermal transport properties of quasicrystals. AlPdMn quasicrystal samples were prepared with various levels of Re substituted for the Mn (Al70Pd20Mn10−XReX) and then subjected to different annealing conditions. Electrical resistivity, thermopower and thermal conductivity were measured on each as grown and annealed sample over a broad range of temperature, 10 K < T < 300 K. The relationship between the electrical and thermal transport properties and microstructure will be presented and discussed.
We report room temperature thermopower values and the temperature dependence for several AlPdMn based quasicrystals. In an effort to further understand the complexities of electrical transport in quasicrystalline systems, thermopower data for icosahedral Al71Pd21Mn8-XReX will be presented and discussed. A relation of room temperature thermopower to the curvature of the thermopower is demonstrated. We propose an empirical fit to the thermopower data, utilizing three free variables. The physical significance of the fit parameters is discussed. These results are discussed in brief concerning the relation to the application of quasicrystals for use as thermoelectric materials.
Partially due to their lack of periodic structure, quasicrystals have inherently low thermal conductivity on the order of 1 - 3 W/m-K. AlPdMn quasicrystals exhibit favorable room temperature values of electrical conductivity, 500–800 (Ω-cm)-1, and thermopower, 80 μV/K, with respect to thermoelectric applications. In an effort to further increase the thermopower and hopefully minimize the thermal conductivity via phonon scattering, quartenary Al71Pd21Mn8-XReX quasicrystals were grown. X-ray data confirms that the addition of a fourth element does not alter the quasiperiodicity of the sample. Al71Pd21Mn8-XReX quasicrystals of varying Re concentration were synthesized where x had values of 0, 0.08, 0.25, 0.4, 0.8, 2, 5, 6, and 8. Both thermal and electrical transport property measurements have been performed and are reported.
This chapter focuses on the role played by the periodic bond chain (PBC) theory in predicting the structural morphology, in particular of ionic structures, illustrated by theoretical and experimental research, past and present. Case studies on ammonium dihydroxy-phosphate (NH4H2PO4) or ADP-type structures and fractal gel-grown ammonium chloride are treated in detail. Future prospects are outlined.
The ultimate goal in computational prediction of crystal morphology, when a crystal, molecular or ionic, grows according to a layer-by-layer mechanism, is twofold. First, to estimate the relative growth rates, that is, the ratios Rhikili/Rhjkjlj, for each Pair of faces (hikili) and (hjkjlj) on the growth form. Rhkl is the rate with which (hkl) grows in the normal direction. Second, to describe adequately and for all types of crystal structures, the roughening transition that the growth fronts can undergo; that is, the transition from the ordered, flat-face mode to the disordered, rough-face mode.
The PBC theory (Section 5.2) offers a realistic and well founded simplified description of the complex physical processes occurring in nature, and has in many cases enjoyed gratifying confirmation from experiment. The theory considers the actually observed morphology to be a superposition of: first, a basic generic morphology caused by internal or structural factors and called the theoretical or structural morphology; and second, a habit modification effect caused by external factors, notably the solid–fluid interaction, since in general the fluid will interact differently with the different faces.
We have identified quasicrystals and quasicrystalline approximants as potential candidates for small scale thermoelectric power generation and refrigeration applications. A number of quasicrystalline systems have been investigated, however, the focus in this paper will be on the ALPdMn (typically Al70Pd20Mn10) system. Currently, we are systematically investigating the electrical and thermal transport properties of the AlPdMn quasicrystalline system in relation to differing sample composition, systematic addition of impurities, and different annealing conditions. Several different preparation techniques have been employed in order to determine optimal techniques for maximizing the thermal and electrical properties of this quasicrystalline system for possible thermoelectric applications. Resistivity and thermopower have been performed over a temperature range between 5K and 320K. Thermal conductivity measurements have been performed over a temperature range between 20K and 300K. In the pure, single phase nominally Al70Pd20Mn10 we have observed thermopower values as high as +85 μV/K around room temperature with resistivity values of 1.5 mΩ-cm. Thermal conductivity measurements yield values less than 3 W/m-K. We will discuss how these properties are affected by the parameters we have varied and the trends we have observed so far. We will discuss the future investigations of the electrical and thermal transport properties of quasicrystals in relation to potential thermoelectric applications.
We have begun a systematic investigation the electrical transport properties of the AlPdMn quasicrystalline system. Resistivity and thermopower measurements have been performed over a temperature range between 5K and 320K. In the pure, single phase Al70Pd20Mn10 we have observed thermopowers as high as +80 μV/K around room temperature with resistivities of 1.5 mΩ-cm. Thermal conductivity measurements have been performed yielding values less than 2 W/m-K for all the samples investigated to date. We will discuss how the thermopower and resistivity vary as a result of differing sample composition as well as different processing and annealing conditions. Several different preparation techniques have been employed to further understand how various factors affect the thermal and electrical properties of this quasicrystalline system and how these may be adjusted to optimize these materials for possible thermoelectric applications.