A PTAS for Scheduling Unrelated Machines of Few Different Types

Scheduling on Unrelated Machines is a classical optimization problem where $n$ jobs have to be distributed to $m$ machines. Each of the jobs $j \in \{1, \ldots, n\}$ has on machine $i \in \{1, \ldots, m\}$ a processing time $p_{ij} \geq 0$. The goal is to minimize the makespan, i.e.\ the maximum completion time of the longest-running machine. Unless $P = NP$, this problem does not allow for a polynomial-time approximation algorithm with a ratio better than $\frac{3}{2}$. A natural scenario is however that many machines are of the same type, like a CPU and GPU cluster: for each of the $K$ machine types, the machines $i \neq i'$ of the same type $k$ satisfy $p_{ij} = p_{i'j}$ for all jobs $j$. For the case where the number $K$ of machine types is constant, this paper presents an approximation scheme, i.e.\ an algorithm of approximation ratio $1+\varepsilon$ for $\varepsilon > 0$, with an improved running time only single exponential in $\frac{1}{\varepsilon}$

Traffic-Related Air Pollution and Incident Type 2 Diabetes: Results from the SALIA Cohort Study

BACKGROUND: Cross-sectional and ecological studies indicate that air pollution may be a risk factor for type 2 diabetes, but prospective data are lacking. OBJECTIVE: We examined the association between traffic-related air pollution and incident type 2 diabetes. DESIGN: Between 1985 and 1994, cross-sectional surveys were performed in the highly industrialized Ruhr district (West Germany); a follow-up investigation was conducted in 2006 using data from the Study on the Influence of Air Pollution on Lung, Inflammation and Aging (SALIA) cohort. PARTICIPANTS: 1,775 nondiabetic women who were 54-55 years old at baseline participated in both baseline and follow-up investigations and had complete information available. MATERIALS AND METHODS: Using questionnaires, we assessed 16-year incidence (1990-2006) of type 2 diabetes and information about covariates. Complement factor C3c as marker for subclinical inflammation was measured at baseline. Individual exposure to traffic-related particulate matter (PM) and nitrogen dioxide was determined at different spatial scales. RESULTS: Between 1990 and 2006, 87 (10.5%) new cases of diabetes were reported among the SALIA cohort members. The hazards for diabetes were increased by 15-42% per interquartile range of PM or traffic-related exposure. The associations persisted when different spatial scales were used to assess exposure and remained robust after adjusting for age, body mass index, socioeconomic status, and exposure to several non-traffic-related sources of air pollution. C3c was associated with PM pollution at baseline and was a strong independent predictor of incident diabetes. Exploratory analyses indicated that women with high C3c blood levels were more susceptible for PM-related excess risk of diabetes than were women with low C3c levels. CONCLUSIONS: Traffic-related air pollution is associated with incident type 2 diabetes among elderly women. Subclinical inflammation may be a mechanism linking air pollution with t 2 diabetes.Relevance to clinical practice: Our study identifies traffic-related air pollution as a novel and potentially modifiable risk factor of type 2 diabete

Framework and baseline examination of the German National Cohort (NAKO)

The German National Cohort (NAKO) is a multidisciplinary, population-based prospective cohort study that aims to investigate the causes of widespread diseases, identify risk factors and improve early detection and prevention of disease. Specifically, NAKO is designed to identify novel and better characterize established risk and protection factors for the development of cardiovascular diseases, cancer, diabetes, neurodegenerative and psychiatric diseases, musculoskeletal diseases, respiratory and infectious diseases in a random sample of the general population. Between 2014 and 2019, a total of 205,415 men and women aged 19–74 years were recruited and examined in 18 study centres in Germany. The baseline assessment included a face-to-face interview, self-administered questionnaires and a wide range of biomedical examinations. Biomaterials were collected from all participants including serum, EDTA plasma, buffy coats, RNA and erythrocytes, urine, saliva, nasal swabs and stool. In 56,971 participants, an intensified examination programme was implemented. Whole-body 3T magnetic resonance imaging was performed in 30,861 participants on dedicated scanners. NAKO collects follow-up information on incident diseases through a combination of active follow-up using self-report via written questionnaires at 2–3 year intervals and passive follow-up via record linkages. All study participants are invited for re-examinations at the study centres in 4–5 year intervals. Thereby, longitudinal information on changes in risk factor profiles and in vascular, cardiac, metabolic, neurocognitive, pulmonary and sensory function is collected. NAKO is a major resource for population-based epidemiology to identify new and tailored strategies for early detection, prediction, prevention and treatment of major diseases for the next 30 years. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10654-022-00890-5

Selbstberichtete Krebserkrankungen in der NAKO Gesundheitsstudie: Erfassungsmethoden und erste Ergebnisse

BACKGROUND: In the German National Cohort (NAKO Gesundheitsstudie), the largest prospective cohort study in Germany, data on self-reported cancer diagnoses are now available for the first half of participants. OBJECTIVES: Description of the methods to assess self-reported cancer diagnoses and type of cancer in the NAKO and presentation of first results. MATERIALS AND METHODS: In a computer-assisted, standardized personal interview, 101,787 participants (54,526 women, 47,261 men) were asked whether they had ever been diagnosed with cancer (malignant tumors including in situ) by a physician and how many cancer diagnoses they had. The type of cancer was classified with a list. Absolute and relative frequencies of self-reported cancer diagnoses and types of cancer were calculated and compared with cancer registry data. RESULTS: A physician-diagnosed cancer was reported by 9.4% of women and 7.0% of men. Of the participants who reported a cancer diagnosis, 88.3% reported to have had only one cancer diagnosis. In women, the most frequent malignancies were breast cancer, cervical cancer, and melanoma. In men, the most frequent malignancies were prostate cancer, melanoma, and colorectal cancer. Comparing the frequencies of cancer diagnoses reported by 45- to 74-year-old NAKO participants within the last five years to cancer registry-based 5‑year prevalences, most types of cancer were less frequent in the NAKO, with the exception of melanoma in men and women, cervical cancer and liver cancer in women, and bladder cancer and breast cancer in men. CONCLUSIONS: The NAKO is a rich data basis for future investigations of incident cancer

European and multi-ancestry genome-wide association meta-analysis of atopic dermatitis highlights importance of systemic immune regulation

Atopic dermatitis (AD) is a common inflammatory skin condition and prior genome-wide association studies (GWAS) have identified 71 associated loci. In the current study we conducted the largest AD GWAS to date (discovery N = 1,086,394, replication N = 3,604,027), combining previously reported cohorts with additional available data. We identified 81 loci (29 novel) in the European-only analysis (which all replicated in a separate European analysis) and 10 additional loci in the multi-ancestry analysis (3 novel). Eight variants from the multi-ancestry analysis replicated in at least one of the populations tested (European, Latino or African), while two may be specific to individuals of Japanese ancestry. AD loci showed enrichment for DNAse I hypersensitivity and eQTL associations in blood. At each locus we prioritised candidate genes by integrating multi-omic data. The implicated genes are predominantly in immune pathways of relevance to atopic inflammation and some offer drug repurposing opportunities.</p

Messung der körperlichen Fitness in der NAKO Gesundheitsstudie: Methoden, Qualitätssicherung und erste deskriptive Ergebnisse

Die körperliche Fitness ist das Maß für die individuelle Fähigkeit, körperlich aktiv zu sein. Ihre wesentlichen Komponenten sind die kardiorespiratorische Fitness (Cardiorespiratory Fitness, CRF), die Muskelkraft und die Beweglichkeit. Neben der körperlichen Aktivität ist die körperliche Fitness ein wesentlicher Prädiktor für Morbidität und Mortalität. Ziel der Arbeit sind die Beschreibung der Erhebungsmethoden körperlicher Fitness in der NAKO Gesundheitsstudie und die Darstellung erster deskriptiver Ergebnisse. In der NAKO-Basiserhebung wurden die maximale Handgreifkraft (Grip Strength, GS) und die CRF als Komponenten der körperlichen Fitness über ein Handdynamometer bzw. über einen Fahrradergometertest mit submaximaler Belastung erhoben. Daraus wurde die maximale Sauerstoffaufnahme (VO2max) zur Beurteilung der CRF abgeleitet. Die Ergebnisse von insgesamt 99.068 GS-Messungen und 3094 Messungen der CRF beruhen auf einem Datensatz zur Halbzeit der Basiserhebung der NAKO (Alter 20–73 Jahre, 47 % Männer). Männer zeigten im Vergleich zu Frauen höhere Werte der körperlichen Fitness (Männer: GS = 47,8 kg, VO2max = 36,4 ml·min−1 · kg−1; Frauen: GS = 29,9 kg, VO2max = 32,3 ml·min−1 · kg−1). Ungefähr ab dem 50. Lebensjahr konnte ein Rückgang der GS verzeichnet werden, wohingegen die CRF ab der Altersgruppe 20–29 Jahre bis zu den ≥60-Jährigen kontinuierlich abfiel. Die GS und die VO2max zeigten nach Korrektur für das Körpergewicht einen linear positiven Zusammenhang (Männer β = 0,21; Frauen β = 0,35). Die Analysen zeigten eine gute Übereinstimmung der Verteilung der körperlichen Fitness in der NAKO im Vergleich zu anderen bevölkerungsbasierten Studien. Zukünftige Auswertungen werden insbesondere die unabhängige Bedeutung der GS und CRF bei der Prädiktion von Morbidität und Mortalität beleuchten.Physical fitness is defined as an individual’s ability to be physically active. The main components are cardiorespiratory fitness (CRF), muscle strength, and flexibility. Regardless of physical activity level, physical fitness is an important determinant of morbidity and mortality. The aim of the current study was to describe the physical fitness assessment methodology in the German National Cohort (NAKO) and to present initial descriptive results in a subsample of the cohort. In the NAKO, hand grip strength (GS) and CRF as physical fitness components were assessed at baseline using a hand dynamometer and a submaximal bicycle ergometer test, respectively. Maximum oxygen uptake (VO2max) was estimated as a result of the bicycle ergometer test. The results of a total of 99,068 GS measurements and 3094 CRF measurements are based on a data set at halftime of the NAKO baseline survey (age 20–73 years, 47% men). Males showed higher values of physical fitness compared to women (males: GS = 47.8 kg, VO2max = 36.4 ml·min−1 · kg−1; females: GS = 29.9 kg, VO2max = 32.3 ml · min−1 · kg−1). GS declined from the age of 50 onwards, whereas VO2max levels decreased continuously between the age groups of 20–29 and ≥60 years. GS and VO2max showed a linear positive association after adjustment for body weight (males β = 0.21; females β = 0.35). These results indicate that the physical fitness measured in the NAKO are comparable to other population-based studies. Future analyses in this study will focus on examining the independent relations of GS and CRF with risk of morbidity and mortality

Die Basiserhebung der NAKO Gesundheitsstudie: Teilnahme an den Untersuchungsmodulen, Qualitätssicherung und Nutzung von Sekundärdaten

BACKGROUND: The German National Cohort (NAKO) is an interdisciplinary health study aimed at elucidating causes for common chronic diseases and detecting their preclinical stages. This article provides an overview of design, methods, participation in the examinations, and their quality assurance based on the midterm baseline dataset (MBD) of the recruitment. METHODS: More than 200,000 women and men aged 20–69 years derived from random samples of the German general population were recruited in 18 study centers (2014–2019). The data collection comprised physical examinations, standardized interviews and questionnaires, and the collection of biomedical samples for all participants (level 1). At least 20% of all participants received additional in-depth examinations (level 2), and 30,000 received whole-body magnet resonance imaging (MRI). Additional information will be collected through secondary data sources such as medical registries, health insurances, and pension funds. This overview is based on the MBD, which included 101,839 participants, of whom 11,371 received an MRI. RESULTS: The mean response proportion was 18%. The participation in the examinations was high with most of the modules performed by over 95%. Among MRI participants, 96% completed all 12 MRI sequences. More than 90% of the participants agreed to the use of complementary secondary and registry data. DISCUSSION: Individuals selected for the NAKO were willing to participate in all examinations despite the time-consuming program. The NAKO provides a central resource for population-based epidemiologic research and will contribute to developing innovative strategies for prevention, screening and prediction of chronic diseases.HINTERGRUND: Die NAKO Gesundheitsstudie ist ein bundesweites interdisziplinäres Forschungsvorhaben mit dem Ziel, die Ursachen für chronische Krankheiten und deren vorklinische Stadien zu untersuchen. Der Artikel gibt einen Überblick über das Studiendesign, die Methoden, die Teilnahme an den Untersuchungen und ihre Qualitätssicherung zur Halbzeit der Basiserhebung. METHODEN: Für die Basiserhebung wurden mehr als 200.000 Frauen und Männer im Alter von 20–69 Jahren aus Zufallsstichproben der Allgemeinbevölkerung in 18 Studienzentren rekrutiert (2014–2019). Die Basiserhebung beinhaltet Untersuchungen, Befragungen und Biomaterialien für alle Teilnehmerinnen und Teilnehmer (Level 1), ein erweitertes Programm für mindestens 20 % (Level 2) und eine Magnetresonanztomografie (MRT) für 30.000 Teilnehmerinnen und Teilnehmer. Sekundär- und Registerdaten werden über Krankheitsregister, Kranken- und Rentenversicherungen erhoben. Die Auswertung bezieht die Datenbasis zur Halbzeit der Basiserhebung mit 101.839 Teilnehmerinnen und Teilnehmern ein, davon 11.371 mit einer MRT-Untersuchung. ERGEBNISSE: Die mittlere Responsequote zur Halbzeit betrug insgesamt 18 %. Die Teilnahme an den Untersuchungen lag überwiegend bei mehr als 95 %. Bei 96 % der MRT-Teilnehmerinnen und Teilnehmer konnten alle 12 MRT-Sequenzen vollständig durchgeführt werden. Der Erschließung und wissenschaftlichen Nutzung ergänzender Sekundär- und Registerdaten stimmten mehr als 90 % der Teilnehmerinnen und Teilnehmer zu. DISKUSSION: Die Bereitschaft, möglichst alle Untersuchungsmodule durchzuführen, war trotz des zeitlichen Aufwandes außerordentlich hoch. Dadurch wird die NAKO zu einer zentralen Ressource für die epidemiologische Forschung in Deutschland. Sie wird es ermöglichen, neue Strategien zur Früherkennung, Vorhersage und Primärprävention chronischer Krankheiten zu entwickeln

The interplay of family history of depression and early trauma: associations with lifetime and current depression in the German national cohort (NAKO)

INTRODUCTION: Family history of depression and childhood maltreatment are established risk factors for depression. However, how these factors are interrelated and jointly influence depression risk is not well understood. The present study investigated (i) if childhood maltreatment is associated with a family history of depression (ii) if family history and childhood maltreatment are associated with increased lifetime and current depression, and whether both factors interact beyond their main effects, and (iii) if family history affects lifetime and current depression via childhood maltreatment. METHODS: Analyses were based on a subgroup of the first 100,000 participants of the German National Cohort (NAKO), with complete information (58,703 participants, mean age = 51.2 years, 53% female). Parental family history of depression was assessed via self-report, childhood maltreatment with the Childhood Trauma Screener (CTS), lifetime depression with self-reported physician's diagnosis and the Mini-International Neuropsychiatric Interview (MINI), and current depressive symptoms with the depression scale of the Patient Health Questionnaire (PHQ-9). Generalized linear models were used to test main and interaction effects. Mediation was tested using causal mediation analyses. RESULTS: Higher frequencies of the childhood maltreatment measures were found in subjects reporting a positive family history of depression. Family history and childhood maltreatment were independently associated with increased depression. No statistical interactions of family history and childhood maltreatment were found for the lifetime depression measures. For current depressive symptoms (PHQ-9 sum score), an interaction was found, with stronger associations of childhood maltreatment and depression in subjects with a positive family history. Childhood maltreatment was estimated to mediate 7%–12% of the effect of family history on depression, with higher mediated proportions in subjects whose parents had a depression onset below 40 years. Abuse showed stronger associations with family history and depression, and higher mediated proportions of family history effects on depression than neglect. DISCUSSION: The present study confirms the association of childhood maltreatment and family history with depression in a large population-based cohort. While analyses provide little evidence for the joint effects of both risk factors on depression beyond their individual effects, results are consistent with family history affecting depression via childhood maltreatment to a small extent

Physical activity, sedentary behaviour, and childhood asthma: a European collaborative analysis

Objectives To investigate the associations of physical activity (PA) and sedentary behaviour in early childhood with asthma and reduced lung function in later childhood within a large collaborative study. Design Pooling of longitudinal data from collaborating birth cohorts using meta-analysis of separate cohort-specific estimates and analysis of individual participant data of all cohorts combined. Setting Children aged 0–18 years from 26 European birth cohorts. Participants 136 071 individual children from 26 cohorts, with information on PA and/or sedentary behaviour in early childhood and asthma assessment in later childhood. Main outcome measure Questionnaire-based current asthma and lung function measured by spirometry (forced expiratory volume in 1 s (FEV1), FEV1/forced vital capacity) at age 6–18 years. Results Questionnaire-based and accelerometry-based PA and sedentary behaviour at age 3–5 years was not associated with asthma at age 6–18 years (PA in hours/day adjusted OR 1.01, 95% CI 0.98 to 1.04; sedentary behaviour in hours/day adjusted OR 1.03, 95% CI 0.99 to 1.07). PA was not associated with lung function at any age. Analyses of sedentary behaviour and lung function showed inconsistent results. Conclusions Reduced PA and increased sedentary behaviour before 6 years of age were not associated with the presence of asthma later in childhood. Data availability statement Due to data protection reasons, the datasets generated during the current study cannot be made publicly available. The cohort-specific datasets are available to interested researchers on reasonable request, provided the release is consistent with the obtained consent of the study participants of the cohort. This will not be possible for all cohorts involved. Ethical approval might be necessary to be obtained for the release and a data transfer agreement must be accepted