Counting Small Induced Subgraphs with Edge-monotone Properties

We study the parameterized complexity of #IndSub($\Phi$), where given a graph $G$ and an integer $k$, the task is to count the number of induced subgraphs on $k$ vertices that satisfy the graph property $\Phi$. Focke and Roth [STOC 2022] completely characterized the complexity for each $\Phi$ that is a hereditary property (that is, closed under vertex deletions): #IndSub($\Phi$) is #W[1]-hard except in the degenerate cases when every graph satisfies $\Phi$ or only finitely many graphs satisfy $\Phi$. We complement this result with a classification for each $\Phi$ that is edge monotone (that is, closed under edge deletions): #IndSub($\Phi$) is #W[1]-hard except in the degenerate case when there are only finitely many integers $k$ such that $\Phi$ is nontrivial on $k$-vertex graphs. Our result generalizes earlier results for specific properties $\Phi$ that are related to the connectivity or density of the graph. Further, we extend the #W[1]-hardness result by a lower bound which shows that #IndSub($\Phi$) cannot be solved in time $f(k) \cdot |V(G)|^{o(\sqrt{\log k/\log\log k})}$ for any function $f$, unless the Exponential-Time Hypothesis (ETH) fails. For many natural properties, we obtain even a tight bound $f(k) \cdot |V(G)|^{o(k)}$; for example, this is the case for every property $\Phi$ that is nontrivial on $k$-vertex graphs for each $k$ greater than some $k_0$

Radikalisierung im Internet: ein systematischer Überblick über Forschungsstand, Wirkungsebenen sowie Implikationen für Wissenschaft und Praxis

Im Zuge des Medienwandels und der stetigen Ausdifferenzierung verfügbarer Online-Angebote verlagert sich nicht nur das alltägliche Leben zunehmend ins Digitale, sondern auch die Aktivitäten extremistischer Akteure. In Folge technologischer und gesellschaftlicher Entwicklungen (z.B. hinsichtlich zunehmender Gewaltbereitschaft im Rahmen von Covid-19-Demonstrationen) rücken Befürchtungen, das Internet könne eine Radikalisierung fördern, in den Fokus wissenschaftlicher und öffentlicher Debatten. Die Durchdringung des Alltags durch das Internet ist daher auch zentral bei der Analyse, Diskussion und Prävention von Radikalisierungsdynamiken. Die genaue Rolle des Internets in Radikalisierungsprozessen hängt dabei von verschiedenen Faktoren ab. Anhand einer systematischen Literaturanalyse von 216 Publikationen zu Radikalisierung im Internet wird ein Überblick über das Forschungsfeld generiert. Die Systematisierung der Literatur erfolgt auf drei Betrachtungsebenen, nämlich (1) der Unterscheidung von Wirkmechanismen auf Mikro-, Meso- und Makroebene, (2) der Modellierung von Radikalisierungsdynamiken entlang des Kommunikationsprozesses (Kommunikator:innen, Inhalt, Medium, Rezipient:innen) sowie (3) der differenzierten Betrachtung unterschiedlicher digitaler Räume im Kontext ihrer Nutzungspotenziale (Affordanzen) für extremistische Akteure. Darauf aufbauend werden Forschungslücken und Potenziale für künftige Studien sowie Handlungsempfehlungen für Akteure aus Praxis und Politik abgeleitet. Die Analyse verdeutlicht: Das Internet kann Radikalisierungsdynamiken beschleunigen, indem es die Effektivität und Effizienz potenziell radikalisierender Kommunikationsprozesse erhöht, beispielsweise durch den Zugang zu größeren, globalen Zielgruppen oder Reichweitensteigerung. Extremistische Akteure nutzen das volle Angebotspotenzial und multimediale Inhalte (z.B. Videos, Podcasts, Memes) werden mit teils hohem Aufwand zielgruppenorientiert produziert. Die Angebotsstrukturen des Internets und (alternativer) sozialer Medien ermöglichen auch eine Selbstradikalisierung unabhängig von Offline-Kontakten. Auf unmoderierten Plattformen werden extremistische Inhalte, Hassrede und Hetze verbreitet, Anschlagsplanung ermöglicht und Fringe Communities, die thematisch zum Teil hochgradig spezifisch erscheinen (z.B. Incels, Manosphere) und trotzdem ideologische Überschneidungen zu bekannten extremistischen Bewegungen haben, können gedeihen. Die großen sozialen Medienplattformen sind weiterhin zentral für extremistische Akteure zur Reichweitengenerierung, Rekrutierung sowie Mobilisierung. Online-Radikalisierung ist niemals von Offline-Geschehen entkoppelt und eine Trennung von digital versus 'realweltlich' ist wenig zielführend, weil Internetnutzung ein zunehmend selbstverständlicher Bestandteil des Alltags ist. Welche Charakteristika digitaler Kommunikationsangebote Radikalisierung fördern und in welchem Umfang, kann auf Basis des aktuellen Forschungsstandes nicht ausreichend beantwortet werden. Das liegt 1) allgemein an der Komplexität der Erforschung von Radikalisierungsdynamiken, 2) der noch dünnen Befundlage zu Online-Radikalisierung, 3) der hohen Schwierigkeit und Kosten, die Kommunikationsdiffusion über digitale Räume hinweg zu erforschen, 4) der Verantwortungsverweigerung von Plattformunternehmen und 5) der Dynamik technischer Veränderung und digitaler Infrastrukturen. Um Online-Radikalisierung besser zu verstehen, müssen die Forschungslücken adressiert werden. Erweiterungsbedarf besteht unter anderem bei der Entwicklung und empirischen Überprüfung von Indikatoren für Online-Radikalisierungsdynamiken, aber auch bei Untersuchungen zu Gruppenprozessen sowie Betrachtungen im Längsschnitt. Wissenschaft, Prävention, Politik und Sicherheitsbehörden müssen im kontinuierlichen Austausch stehen, wenn in Gewalt kulminierende Radikalisierungsdynamiken sowie Extremismus konsequent begegnet werden soll

Gastrointestinal Stromal Tumors: Clinical Symptoms, Location, Metastasis Formation, and Associated Malignancies in a Single Center Retrospective Study

Background and Aims: Gastrointestinal stromal tumors (GISTs) are rare malignancies but the most common mesenchymal tumors of the digestive tract. Recent advances in diagnostic imaging and an increasing incidence will confront us more frequently with stromal tumors. This single center study aimed to characterize GIST patients in terms of tumor location, clinical presentation, metastasis formation, as well as associated secondary malignancies. Methods: In a retrospective study, 104 patients with a histologically confirmed diagnosis of GIST, collected between 1993 and 2011, were characterized for several clinical features. Results: The most common GIST location was the stomach (67.6%) followed by the small intestine (16.2%). Gastrointestinal bleeding (55.8%) and abdominal pain (38.5%) were the most frequently reported symptoms whereas about one-third of patients remained clinically asymptomatic (31.6%); 14.4% of patients had either synchronous or metachronous metastases and there was a significant prevalence also in the low risk group. The proportion of secondary malignant associated neoplasms was 31% in our GIST cohort, among which gastrointestinal, genitourinary tumors, and breast cancer were the most prevalent. Conclusion: There was a considerable risk for metastasis formation and the development of secondary neoplasias that should encourage discussion about the appropriate surveillance strategy after surgery for GIST

Reproductive Factors and Serum Uric Acid Levels in Females from the General Population: The KORA F4 Study

Hyperuricemia is associated with an increased risk of metabolic and cardiovascular diseases. There are pronounced sex differences in the levels of uric acid. It is largely unknown whether or not reproductive parameters which induce hormonal changes are responsible for this. We examined if there are associations between reproductive parameters and uric acid levels in a female population-based sample. In this cross-sectional analysis, data of 1530 women aged 32 to 81 years participating in the KORA F4 study, conducted between 2006 and 2008 in Southern Germany were used. Reproductive parameters were obtained by standardized interviews. Uric acid levels were tested by the uricase method. The whole study sample and stratified in pre- and postmenopausal women was analyzed. Menopausal status and earlier age at menarche were associated with higher serum uric acid levels (age-adjusted: p-values 0.003, <0.001 respectively; after multivariable adjustment, including BMI: p-values 0.002, 0.036). A history of oral contraceptive use showed an association with uric acid levels only after multivariable adjustment (p-value 0.009). Hot flushes showed an association with uric acid levels only after age-adjustment (p-value 0.038), but lost significance after adding other confounders. Other reproductive factors, including parity, current or ever use of hormone replacement therapy, current use of oral contraceptives, hysterectomy, bilateral oophorectomy, or depressive mood related to menopausal transition were not associated with uric acid levels. Postmenopausal status, earlier age at menarche and a history of oral contraceptive use were independently associated with higher serum uric acid concentrations in women from the general population. Further studies, especially longitudinal population-based studies investigating the relationship of female reproductive parameters with uric acid levels are necessary to confirm our findings

Abdominal aortic aneurysm is associated with a variant in low-density lipoprotein receptor-related protein 1

Abdominal aortic aneurysm (AAA) is a common cause of morbidity and mortality and has a significant heritability. We carried out a genome-wide association discovery study of 1866 patients with AAA and 5435 controls and replication of promising signals (lead SNP with a p value &lt; 1 × 10-5) in 2871 additional cases and 32,687 controls and performed further follow-up in 1491 AAA and 11,060 controls. In the discovery study, nine loci demonstrated association with AAA (p &lt; 1 × 10-5). In the replication sample, the lead SNP at one of these loci, rs1466535, located within intron 1 of low-density-lipoprotein receptor-related protein 1 (LRP1) demonstrated significant association (p = 0.0042). We confirmed the association of rs1466535 and AAA in our follow-up study (p = 0.035). In a combined analysis (6228 AAA and 49182 controls), rs1466535 had a consistent effect size and direction in all sample sets (combined p = 4.52 × 10-10, odds ratio 1.15 [1.10-1.21]). No associations were seen for either rs1466535 or the 12q13.3 locus in independent association studies of coronary artery disease, blood pressure, diabetes, or hyperlipidaemia, suggesting that this locus is specific to AAA. Gene-expression studies demonstrated a trend toward increased LRP1 expression for the rs1466535 CC genotype in arterial tissues; there was a significant (p = 0.029) 1.19-fold (1.04-1.36) increase in LRP1 expression in CC homozygotes compared to TT homozygotes in aortic adventitia. Functional studies demonstrated that rs1466535 might alter a SREBP-1 binding site and influence enhancer activity at the locus. In conclusion, this study has identified a biologically plausible genetic variant associated specifically with AAA, and we suggest that this variant has a possible functional role in LRP1 expression

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

Genome-wide association study identifies six new loci influencing pulse pressure and mean arterial pressure.

Numerous genetic loci have been associated with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in Europeans. We now report genome-wide association studies of pulse pressure (PP) and mean arterial pressure (MAP). In discovery (N = 74,064) and follow-up studies (N = 48,607), we identified at genome-wide significance (P = 2.7 × 10(-8) to P = 2.3 × 10(-13)) four new PP loci (at 4q12 near CHIC2, 7q22.3 near PIK3CG, 8q24.12 in NOV and 11q24.3 near ADAMTS8), two new MAP loci (3p21.31 in MAP4 and 10q25.3 near ADRB1) and one locus associated with both of these traits (2q24.3 near FIGN) that has also recently been associated with SBP in east Asians. For three of the new PP loci, the estimated effect for SBP was opposite of that for DBP, in contrast to the majority of common SBP- and DBP-associated variants, which show concordant effects on both traits. These findings suggest new genetic pathways underlying blood pressure variation, some of which may differentially influence SBP and DBP

Contributions of mean and shape of blood pressure distribution to worldwide trends and variations in raised blood pressure: A pooled analysis of 1018 population-based measurement studies with 88.6 million participants

© The Author(s) 2018. Background: Change in the prevalence of raised blood pressure could be due to both shifts in the entire distribution of blood pressure (representing the combined effects of public health interventions and secular trends) and changes in its high-blood-pressure tail (representing successful clinical interventions to control blood pressure in the hypertensive population). Our aim was to quantify the contributions of these two phenomena to the worldwide trends in the prevalence of raised blood pressure. Methods: We pooled 1018 population-based studies with blood pressure measurements on 88.6 million participants from 1985 to 2016. We first calculated mean systolic blood pressure (SBP), mean diastolic blood pressure (DBP) and prevalence of raised blood pressure by sex and 10-year age group from 20-29 years to 70-79 years in each study, taking into account complex survey design and survey sample weights, where relevant. We used a linear mixed effect model to quantify the association between (probittransformed) prevalence of raised blood pressure and age-group- and sex-specific mean blood pressure. We calculated the contributions of change in mean SBP and DBP, and of change in the prevalence-mean association, to the change in prevalence of raised blood pressure. Results: In 2005-16, at the same level of population mean SBP and DBP, men and women in South Asia and in Central Asia, the Middle East and North Africa would have the highest prevalence of raised blood pressure, and men and women in the highincome Asia Pacific and high-income Western regions would have the lowest. In most region-sex-age groups where the prevalence of raised blood pressure declined, one half or more of the decline was due to the decline in mean blood pressure. Where prevalence of raised blood pressure has increased, the change was entirely driven by increasing mean blood pressure, offset partly by the change in the prevalence-mean association. Conclusions: Change in mean blood pressure is the main driver of the worldwide change in the prevalence of raised blood pressure, but change in the high-blood-pressure tail of the distribution has also contributed to the change in prevalence, especially in older age groups