The merger boom: an overview

Consolidation and merger of corporations ; Corporations ; Public policy

Are hostile takeovers different?

Consolidation and merger of corporations ; Corporations ; Stockholders

The Vertex-Face Correspondence and the Elliptic 6j-symbols

A new formula connecting the elliptic $6j$-symbols and the fusion of the vertex-face intertwining vectors is given. This is based on the identification of the $k$ fusion intertwining vectors with the change of base matrix elements from Sklyanin's standard base to Rosengren's natural base in the space of even theta functions of order $2k$. The new formula allows us to derive various properties of the elliptic $6j$-symbols, such as the addition formula, the biorthogonality property, the fusion formula and the Yang-Baxter relation. We also discuss a connection with the Sklyanin algebra based on the factorised formula for the $L$-operator.Comment: 23 page

Effects of an 8-year childhood physical activity intervention on musculoskeletal gains and fracture risk

Background Physical activity (PA) in childhood is associated with musculoskeletal benefits while the effect on fracture risk is yet to be determined. The aim of this study was to evaluate whether extension of a PA intervention leads to improvement in musculoskeletal traits with an accompanied reduced fracture risk. We hypothesized that the PA program would have beneficial effects in both sexes, but more so in girls since they tend to be less physically active than boys during this time frame. Methods In one elementary school we increased physical education (PE) from 60 to 200 min per school week and followed 65 girls and 93 boys from a mean age of 7 years until a mean age of 15 years. Thirty-nine girls and 37 boys in three other schools continued with 60 min of PE per week during the same years and served as controls. We measured bone mineral content (BMC), areal bone mineral density (aBMD), and bone area annually with dual energy X-ray absorptiometry, and leg muscle strength with a computerized dynamometer. In 3534 children within the same PE program (1339 in the intervention and 2195 in the control group) we registered incident fractures during the 8-year study period and estimated annual sex-specific fracture incidence rate ratios (IRRs). Results Girls in the intervention group annually gained more total body less head aBMD, spine aBMD (p < 0.01), femoral neck BMC (p < 0.05), lumbar vertebrae size (p < 0.05), and knee flexion strength (p < 0.05) than girls in the control cohort. In boys we found no group differences. There was an inverse correlation between number of years with extra PE and the annual IRR of sustaining fractures in both girls (r = − 0.90 (95% CI − 0.98 to − 0.51); p < 0.001) and boys (r = − 0.74 (95% CI − 0.94 to − 0.02); p < 0.05). Conclusion In this 8-year pediatric school-based moderate exercise intervention program there is an inverse correlation in both sexes between annual IRR and each additional year of extra PA. A sub-cohort of girls in the intervention group had greater gains in bone mass, bone size, and muscle strength, which could possibly explain the inverse correlation between years within the PA program and fracture risk, while in boys the reason for the inverse correlation remains unknown. It should be noted that differences in unreported factors such as skeletal maturity status, diet, and spare time PA could confound our inferences. That is, true causality cannot be stated

Prediction of Outcome After Endovascular Embolectomy in Anterior Circulation Stroke Using Biomarkers

Stroke is a major public health problem that can cause a long-term disability or death due to brain damage. Serious stroke is frequently caused by a large vessel occlusion in the anterior circulation, which should be treated by endovascular embolectomy if possible. In this study, we investigated the use of the brain damage biomarkers tau, NFL, NSE, GFAp, and S100B to understand the progression of nervous tissue damage and their relationship to outcome in such stroke after endovascular treatment. Blood samples were taken from 90 patients pre-treatment and 2 h, 24 h, 48 h, 72 h and 3 months after endovascular treatment. Stroke-related neurological deficit was estimated using the National Institute of Health Stroke Scale (NIHSS) at admission and at 24 h. Neurological outcome was evaluated at 3 months. After stroke, tau, NFL, GFAp and S100B increased in a time dependent manner, while NSE remained constant over time. At 3 months, tau and GFAp levels were back to normal whereas NFL was still high. Tau, NFL and GFAp correlated well to outcome, as well as to infarct volume and NIHSS at 24 h. The best time for prediction of poor outcome was different for each biomarker. However, the combination of NIHSS at 24 h with either tau, NFL or GFAp at 48 h gave the best prediction. The use of biomarkers in the early setting after endovascular treatment of stroke will lead to a simplified and standardized way to estimate the nervous tissue damage and possibly complement the clinical judgement in foreseeing the need of rehabilitation measures

BMI, sex and outcomes in hospitalised patients in western Sweden during the COVID-19 pandemic

High body mass index (BMI) is associated with severe COVID-19 but findings regarding the need of intensive care (IC) and mortality are mixed. Using electronic health records, we identified all patients in western Sweden hospitalised with COVID-19 to evaluate 30-day mortality or assignment to IC. Adjusted logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals (CI) for outcomes. Of totally 9761 patients, BMI was available in 7325 (75%), included in the study. There was a marked inverse association between BMI and age (underweight and normal weight patients were on average 78 and 75\ua0years, whereas overweight and obese were 68 and 62\ua0years). While older age, male sex and several comorbidities associated with higher mortality after multivariable adjustment, BMI did not. However, BMI ≥ 30\ua0kg/m2\ua0(OR 1.46, 95% CI 1.21–1.75) was associated with need of IC; this association was restricted to women (BMI ≥ 30; OR 1.96 (95% CI 1.41–2.73), and not significant in men; OR 1.22 (95% CI 0.97–1.54). In this comprehensive hospital population with COVID-19, BMI was not associated with 30-day mortality risk. Among the obese, women, but not men, had a higher risk of assignment to IC

Body Mass Index in young women and risk of cardiomyopathy: a long-term follow-up study in Sweden

Incidence rates of cardiomyopathies, which are a common cause of heart failure in young people, have increased during the last decades. An association between body weight in adolescence and future cardiomyopathy among men was recently identified. Whether or not this holds true also for women is unknown. The aim was therefore to determine whether for young women being overweight or obese is associated with a higher risk of developing cardiomyopathy. This was a registry-based national prospective cohort study with data collected from the Swedish Medical Birth Register, 1982 to 2014, with up to 33 years of follow-up. Included women were of childbearing age (18-45 years) during the initial antenatal visit in their first or second pregnancy (n=1 393 346). We obtained baseline data on body mass index (BMI), smoking, education, and previous disorders. After exclusions, mainly because of previous disorders, the final sample was composed of 1 388 571 women. Cardiomyopathy cases were identified by linking the Medical Birth Register to the National Patient and Cause of Death registers. In total, we identified 1699 cases of cardiomyopathy (mean age at diagnosis, 46.2 [SD 9.1] years) during the follow-up with an incidence rate of 5.9 per 100 000 observation years. Of these, 481 were diagnosed with dilated cardiomyopathy, 246 had hypertrophic cardiomyopathy, 61 had alcohol/drug-induced cardiomyopathy, and 509 had other forms. The lowest risk for being diagnosed with a cardiomyopathy was detected at a BMI of 21 kg/m , with a gradual increase in risk with higher BMI, particularly for dilated cardiomyopathy, where a hazard ratio of 4.71 (95% CI, 2.81-7.89) was found for severely obese subjects (BMI ≥35 kg/m ), as compared with BMI 20 to &lt;22.5. Elevated BMI among young women was associated with an increased risk of being diagnosed with a subsequent cardiomyopathy, especially dilated cardiomyopathy, starting already at mildly elevated body weight, whereas severe obesity entailed an almost 5-fold increase in risk. With the increasing numbers of persons who are overweight or obese, higher rates of cardiomyopathy can be expected in the future, along with an altered disease burden related to adiposity

Three-coloring statistical model with domain wall boundary conditions. I. Functional equations

In 1970 Baxter considered the statistical three-coloring lattice model for the case of toroidal boundary conditions. He used the Bethe ansatz and found the partition function of the model in the thermodynamic limit. We consider the same model but use other boundary conditions for which one can prove that the partition function satisfies some functional equations similar to the functional equations satisfied by the partition function of the six-vertex model for a special value of the crossing parameter.Comment: 16 pages, notations changed for consistency with the next part, appendix adde

Age and sex differences in cause-specific excess mortality and years of life lost associated with COVID-19 infection in the Swedish population

Background Estimating excess mortality and years of life lost (YLL) attributed to coronavirus disease 19 (COVID-19) infection provides a comprehensive picture of the mortality burden on society. We aimed to estimate the impact of the COVID-19 pandemic on age- and sex-specific excess mortality and YLL in Sweden during the first 17 months of the pandemic. Methods In this population-based observational study, we calculated age- and sex-specific excess all-cause mortality and excess YLL during 2020 and the first 5 months of 2021 and cause-specific death [deaths from cardiovascular disease (CVD), cancer, other causes and deaths excluding COVID-19] in 2020 compared with an average baseline for 2017-19 in the whole Swedish population. Results COVID-19 deaths contributed 9.9% of total deaths (98 441 deaths, 960 305 YLL) in 2020, accounting for 75 151 YLL (7.7 YLL/death). There were 2672 (5.7%) and 1408 (3.0%) excess deaths, and 19 141 (3.8%) and 3596 (0.8%) excess YLL in men and women, respectively. Men aged 65-110 years and women aged 75-110 years were the greatest contributors. Fewer deaths and YLL from CVD, cancer and other causes were observed in 2020 compared with the baseline adjusted to the population size in 2020. Conclusions Compared with the baseline, excess mortality and YLL from all causes were experienced in Sweden during 2020, with a higher excess observed in men than in women, indicating that more men died at a younger age while more women died at older ages than expected. A notable reduction in deaths and YLL due to CVD suggests a displacement effect from CVD to COVID-19