Dyons with axial symmetry

We construct axially symmetric dyons in SU(2) Yang-Mills-Higgs theory. In the Prasad-Sommerfield limit, they are obtained via scaling relations from axially symmetric multimonopole solutions. For finite Higgs self-coupling they are constructed numerically.Comment: 9 pages, 5 Postscript figures, 2 references adde

Electrically Charged Sphalerons

We investigate the possibility that the Higgs sector of the Weinberg-Salam model admits the existence of electrically charged, sphaleron states. Evidence is provided through an asymptotic and numerical perturbative analysis about the uncharged sphaleron. By introducing a toy model in two dimensions we demonstrate that such electrically charged, unstable states can exist. Crucially, they can have a comparable mass to their uncharged counterparts and so may also play a role in electroweak baryogenesis, by opening up new channels for baryon number violating processes.Comment: 12 pages, 4 Postscript figure

Existence of spinning solitons in gauge field theory

We study the existence of classical soliton solutions with intrinsic angular momentum in Yang-Mills-Higgs theory with a compact gauge group $\mathcal{G}$ in (3+1)-dimensional Minkowski space. We show that for \textit{symmetric} gauge fields the Noether charges corresponding to \textit{rigid} spatial symmetries, as the angular momentum, can be expressed in terms of \textit{surface} integrals. Using this result, we demonstrate in the case of $\mathcal{G}=SU(2)$ the nonexistence of stationary and axially symmetric spinning excitations for all known topological solitons in the one-soliton sector, that is, for 't Hooft--Polyakov monopoles, Julia-Zee dyons, sphalerons, and also vortices.Comment: 21 pages, to appear in Phys.Rev.

Reproductive success of Bornean orangutan males: scattered in time but clustered in space

The social and mating systems of orangutans, one of our closest relatives, remain poorly understood. Orangutans (Pongo spp.) are highly sexually dimorphic and females are philopatric and maintain individual, but overlapping home ranges, whereas males disperse, are non-territorial and wide-ranging, and show bimaturism, with many years between reaching sexual maturity and attaining full secondary sexual characteristics (including cheek pads (flanges) and emitting long calls). We report on 21 assigned paternities, among 35 flanged and 15 unflanged, genotyped male Bornean orangutans (Pongo pygmaeus wurmbii), studied from 2003 to 2018 in Tuanan (Central Kalimantan, Indonesia). All 10 infants born since mid-2003 with an already identified sire were sired by flanged males. All adult males ranged well beyond the study area (c. 1000 ha), and their dominance relations fluctuated even within short periods. However, 5 of the 10 identified sires had multiple offspring within the monitored area. Several sired over a period of c. 10 years, which overlapped with siring periods of other males. The long-calling behavior of sires indicated they were not consistently dominant over other males in the area around the time of known conceptions. Instead, when they were seen in the area, the known sires spent most of their time within the home ranges of the females whose offspring they sired. Overall, successful sires were older and more often resident than others. Significance statement It is difficult to assess reproductive success for individuals of long-lived species, especially for dispersing males, who cannot be monitored throughout their lives. Due to extremely long interbirth intervals, orangutans have highly male-skewed operational sex ratios and thus intensive male-male competition for every conception. Paternity analyses matched 21 immature Bornean orangutans with their most likely sire (only 10 of 50 genotyped males) in a natural population. Half of these identified sires had multiple offspring in the study area spread over periods of at least 10 years, despite frequently ranging outside this area. Dominance was a poor predictor of success, but, consistent with female mating tactics to reduce the risk of infanticide, known “sires” tended to have relatively high local presence, which seems to contribute to the males’ siring success. The results highlight the importance of large protected areas to enable a natural pattern of dispersal and ranging

Alternative reproductive tactics of unflanged and flanged male orangutans revisited

In many slowly developing mammal species, males reach sexual maturity well before they develop secondary sexual characteristics. Sexually mature male orangutans have exceptionally long periods of developmental arrest. The two male morphs have been associated with behavioral alternative reproductive tactics, but this interpretation is based on cross‐sectional analyses predominantly of Northwest Sumatran populations. Here we present the first longitudinal analyses of behavioral changes of 10 adult males that have been observed in both unflanged and flanged morph. We also analyzed long‐term behavioral data on an additional 143 individually identified males from two study sites, Suaq (Sumatra, Pongo abelii) and Tuanan (Borneo, Pongo pygmaeus wurmbii), to assess male mating tactics cross‐sectionally in relation to population, male morph (unflanged and flanged), and other socio‐ecological factors. Both our longitudinal and cross‐sectional results confirm and refine previous cross‐sectional accounts of the differences in mating tactics between the unflanged and the flanged male morphs. In the unflanged morph, males exhibit higher sociability, particularly with females, and higher rates of both copulation and sexual coercion than in the flanged morph. Based on our results and those of previous studies showing that females prefer flanged males, and that flanged males have higher reproductive success, we conclude that unflanged males face a trade‐off between avoiding male‐male contest competition and gaining mating access to females, and thus follow a “best‐of‐a‐bad‐job” mating strategy

Effectiveness of a Long-term Home-Based Exercise Training Program in Patients With COPD After Pulmonary Rehabilitation: A Multicenter Randomized Controlled Trial

Background: Most patients with COPD do not maintain exercise training after pulmonary rehabilitation (PR). Research question: Does a 12-month home-based, minimal-equipment strength training program after PR have an effect on dyspnea, exercise capacity, and patient-reported outcomes in patients with COPD? Study design and methods: In a parallel-arm multicenter study across four Swiss PR clinics, patients with COPD were allocated randomly (1:1 ratio) into an intervention group (IG; home-based strength training program) or control group (CG; usual care). The primary outcome was change in Chronic Respiratory Questionnaire (CRQ) dyspnea scale score from baseline to 12 months. Secondary outcomes were change in exercise capacity (1-min sit-to-stand-test [1MSTST], 6-min walk test [6MWT]), health-related quality of life, exacerbations, and symptoms. We assessed the IG's experience by interviews at study end. Main analyses were based on the intention-to-treat approach, and adjusted linear regression models were used. Results: One hundred twenty-three patients with COPD (IG, n = 61; CG, n = 62) were randomized, 61 of whom were women and whose mean ± SD age was 66.8 ± 8.1 years and mean ± SD FEV1 was 39.3 ± 15.3% predicted. One hundred four participants completed 12 months of follow-up (IG, n= 53; CG, n= 51). Of the 53 IG participants, 37 participants (70%) conducted the training until study end. We found no difference in change in CRQ dyspnea scale score over 12 months (adjusted mean difference, 0.28; 95% CI, -0.23 to 0.80; P = .27). We found moderate evidence for a difference in 1MSTST repetitions favoring the IG (adjusted mean difference, 2.6; 95% CI, 0.22-5.03; P = .033), but no evidence for an effect in other outcomes. Seventy-nine percent of the IG reported positive effects that they attributed to the training. Interpretation: The home exercise program had no effect on dyspnea, but improved 1MSTST performance and patient-perceived fitness. The supported program was well accepted by patients with COPD and may facilitate continued exercise training at home. Trial registry: ClinicalTrials.gov; No.: NCT03461887; URL: www. Clinicaltrials: gov. Keywords: COPD; dyspnea; effectiveness; functional exercise capacity; home-based exercise training; long-term maintenance; minimal equipment; pulmonary rehabilitation; quality of life; randomized controlled tria

Species richness stabilizes productivity via asynchrony and drought-tolerance diversity in a large-scale tree biodiversity experiment

Extreme climatic events threaten forests and their climate mitigation potential globally. Understanding the drivers promoting ecosystem stability is therefore considered crucial for mitigating adverse climate change effects on forests. Here, we use structural equation models to explain how tree species richness, asynchronous species dynamics, species-level population stability, and drought-tolerance traits relate to the stability of forest productivity along an experimentally manipulated species richness gradient ranging from 1 to 24 tree species. Tree species richness improved community stability by increasing asynchrony. That is, at higher species richness, interannual variation in productivity among tree species buffered the community against stress-related productivity declines. This effect was positively related to variation in stomatal control and resistance-acquisition strategies among species, but not to the community-weighted means of these trait syndromes. The identified mechanisms by which tree species richness stabilizes forest productivity emphasize the importance of diverse, mixed-species forests to adapt to climate change

Mutant IDH1 Differently Affects Redox State and Metabolism in Glial Cells of Normal and Tumor Origin

IDH1R132H (isocitrate dehydrogenase 1) mutations play a key role in the development of low-grade gliomas. IDH1wt converts isocitrate to α-ketoglutarate while reducing nicotinamide adenine dinucleotide phosphate (NADP+), whereas IDH1R132H uses α-ketoglutarate and NADPH to generate the oncometabolite 2-hydroxyglutarate (2-HG). While the effects of 2-HG have been the subject of intense research, the 2-HG independent effects of IDH1R132H are still ambiguous. The present study demonstrates that IDH1R132H expression but not 2-HG alone leads to significantly decreased tricarboxylic acid (TCA) cycle metabolites, reduced proliferation, and enhanced sensitivity to irradiation in both glioblastoma cells and astrocytes in vitro. Glioblastoma cells, but not astrocytes, showed decreased NADPH and NAD+ levels upon IDH1R132H transduction. However, in astrocytes IDH1R132H led to elevated expression of the NAD-synthesizing enzyme nicotinamide phosphoribosyltransferase (NAMPT). These effects were not 2-HG mediated. This suggests that IDH1R132H cells utilize NAD+ to restore NADP pools, which only astrocytes could compensate via induction of NAMPT. We found that the expression of NAMPT is lower in patient-derived IDH1-mutant glioma cells and xenografts compared to IDH1-wildtype models. The Cancer Genome Atlas (TCGA) data analysis confirmed lower NAMPT expression in IDH1-mutant versus IDH1-wildtype gliomas. We show that the IDH1 mutation directly affects the energy homeostasis and redox state in a cell-type dependent manner. Targeting the impairments in metabolism and redox state might open up new avenues for treating IDH1-mutant gliomas.publishedVersio

Species richness stabilizes productivity via asynchrony and drought-tolerance diversity in a large-scale tree biodiversity experiment

Extreme climatic events threaten forests and their climate mitigation potential globally. Understanding the drivers promoting ecosystem stability is therefore considered crucial for mitigating adverse climate change effects on forests. Here, we use structural equation models to explain how tree species richness, asynchronous species dynamics, species-level population stability, and drought-tolerance traits relate to the stability of forest productivity along an experimentally manipulated species richness gradient ranging from 1 to 24 tree species. Tree species richness improved community stability by increasing asynchrony. That is, at higher species richness, interannual variation in productivity among tree species buffered the community against stress-related productivity declines. This effect was positively related to variation in stomatal control and resistance-acquisition strategies among species, but not to the community-weighted means of these trait syndromes. The identified mechanisms by which tree species richness stabilizes forest productivity emphasize the importance of diverse, mixed-species forests to adapt to climate change