Deregulation of Letter Markets and its Impact on Process and Product Innovation

Does the European model of end-to-end competition or the US model of worksharing provide stronger innovation incentives for incumbent postal operators? We answer this question based on a two stage model with price competition and product differentiation. We find that incentives for process innovation in the upstream activities are stronger under end-to-end competition. Incentives for process innovation in delivery are stronger under worksharing, assuming that the entrant's demand under worksharing is higher than the decline in the incumbent's demand. Regarding product innovation, incentives depend on the access pric

Structural and paramagnetic properties of dilute Ga1-xMnxN

Systematic investigations of the structural and magnetic properties of single crystal (Ga,Mn)N films grown by metal organic vapor phase epitaxy are presented. High resolution transmission electron microscopy, synchrotron x-ray diffraction, and extended x-ray absorption fine structure studies do not reveal any crystallographic phase separation and indicate that Mn occupies Ga-substitutional sites in the Mn concentration range up to 1%. The magnetic properties as a function of temperature, magnetic field and its orientation with respect to the c-axis of the wurtzite structure can be quantitatively described by the paramagnetic theory of an ensemble of non-interacting Mn$^{3+}$ ions in the relevant crystal field, a conclusion consistent with the x-ray absorption near edge structure analysis. A negligible contribution of Mn in the 2+ charge state points to a low concentration of residual donors in the studied films. Studies on modulation doped p-type (Ga,Mn)N/(Ga,Al)N:Mg heterostructures do not reproduce the high temperature robust ferromagnetism reported recently for this system.Comment: 15 pages, 14 figure

Skeletal muscle alterations in tachycardia-induced heart failure are linked to deficient natriuretic peptide signalling and are attenuated by RAS-/NEP-inhibition

Background Heart failure induced cachexia is highly prevalent. Insights into disease progression are lacking. Methods Early state of left ventricular dysfunction (ELVD) and symptomatic systolic heart failure (HF) were both induced in rabbits by tachypacing. Tissue of limb muscle (LM) was subjected to histologic assessment. For unbiased characterisation of early and late myopathy, a proteomic approach followed by computational pathway-analyses was performed and combined with pathway-focused gene expression analyses. Specimen of thoracic diaphragm (TD) served as control for inactivity-induced skeletal muscle alterations. In a subsequent study, inhibition of the renin-angiotensin-system and neprilysin (RAS-/NEP) was compared to placebo. Results HF was accompanied by loss of protein content (8.7±0.4% vs. 7.0±0.5%, mean±SEM, control vs. HF, p<0.01) and a slow-to-fast fibre type switch, establishing hallmarks of cachexia. In ELVD, the enzymatic set-up of LM and TD shifted to a catabolic state. A disturbed malate-aspartate shuttle went well with increased enzymes of glycolysis, forming the enzymatic basis for enforced anoxic energy regeneration. The histological findings and the pathway analysis of metabolic results drew the picture of suppressed PGC-1α signalling, linked to the natriuretic peptide system. In HF, natriuretic peptide signalling was desensitised, as confirmed by an increase in the ratio of serum BNP to tissue cGMP (57.0±18.6pg/ml/nM/ml vs. 165.8±16.76pg/ml/nM/ml, p<0.05) and a reduced expression of natriuretic peptide receptor-A. In HF, combined RAS-/NEP-inhibition prevented from loss in protein content (8.7±0.3% vs. 6.0±0.6% vs. 8.3±0.9%, Baseline vs. HF-Placebo vs. HF-RAS/NEP, p<0.05 Baseline vs. HF-Placebo, p = 0.7 Baseline vs. HF-RAS/NEP). Conclusions Tachypacing-induced heart failure entails a generalised myopathy, preceding systolic dysfunction. The characterisation of “pre-cachectic” state and its progression is feasible. Early enzymatic alterations of LM depict a catabolic state, rendering LM prone to futile substrate metabolism. A combined RAS-/NEP-inhibition ameliorates cardiac-induced myopathy independent of systolic function, which could be linked to stabilised natriuretic peptide/cGMP/PGC-1α signalling

DLR Design Challenge 2022: Design of a next generation VTOL firefighting aircraft

Since 2017, the German Aerospace Center (DLR) has been organizing an annual student competition on conceptual aircraft design titled DLR Design Challenge. This education and training initiative is set to challenge the next generation of aircraft designers with topics tailored to current research questions in the field of aeronautics. This year’s challenge was about the development of an aerial firefighting system of systems including vehicle and fleet design with a strong emphasize on operationally-driven design aspects. This paper proposes a design for a next generation vertical take-off and landing firefighting aircraft with an expected entry into service in 2030, that is working intelligently and interconnected in a group of four. The design won the DLR Design Challenge 2022 and the underlying work covers the preliminary design including the structural concept, aerodynamic simulations, weight and balance calculations and the concept for water intake and deployment. The designed aircraft is characterized by a considerable high payload ratio that features vertical take-off and landing capabilities while showing efficient horizontal flight properties with a very competitive cost basis. The 24-hr operability during various weather conditions and challenging fire scenarios is ensured using a wide variety of sensors and a modern glass-cockpit combining pilot comfort with indispensable safety aspects. Due to its modular design, every aircraft can be comfortably converted to a passenger or freight version during firefighting off-season or for cargo and crew supply during the missions

DLR DESIGN CHALLENGE 2022: DESIGN OF A NEXT GENERATION VTOL FIREFIGHTING AIRCRAFT

Since 2017, the German Aerospace Center (DLR) has been organizing an annual student competition on conceptual aircraft design titled DLR Design Challenge. This education and training initiative is set to challenge the next generation of aircraft designers with topics tailored to current research questions in the field of aeronautics. This year’s challenge was about the development of an aerial firefighting system of systems including vehicle and fleet design with a strong emphasize on operationally-driven design aspects. This paper proposes a design for a next generation vertical take-off and landing firefighting aircraft with an expected entry into service in 2030, that is working intelligently and interconnected in a group of four. The design won the DLR Design Challenge 2022 and the underlying work covers the preliminary design including the structural concept, aerodynamic simulations, weight and balance calculations and the concept for water intake and deployment. The designed aircraft is characterized by a considerable high payload ratio that features vertical take-off and landing capabilities while showing efficient horizontal flight properties with a very competitive cost basis. The 24-hr operability during various weather conditions and challenging fire scenarios is ensured using a wide variety of sensors and a modern glass-cockpit combining pilot comfort with indispensable safety aspects. Due to its modular design, every aircraft can be comfortably converted to a passenger or freight version during firefighting off-season or for cargo and crew supply during the missions

Genome-wide association study of borderline personality disorder reveals genetic overlap with the bipolar disorder, schizophrenia and major depression

Borderline personality disorder (BOR) is determined by environmental and genetic factors, and characterized by affective instability and impulsivity, diagnostic symptoms also observed in manic phases of Bipolar Disorder (BIP). Up to 20% of BIP patients show comorbidity with BOR. This report describes the first case-control genome-wide association study (GWAS) of BOR, performed in one of the largest BOR patient samples worldwide. The focus of our analysis was: (i) to detect genes and gene-sets involved in BOR; and (ii) to investigate the genetic overlap with BIP. As there is considerable genetic overlap between BIP, Major Depression (MDD) and Schizophrenia (SCZ) and a high comorbidity of BOR and MDD, we also analyzed the genetic overlap of BOR with SCZ and MDD. GWAS, gene-based tests,and gene-set-analyses were performed in 998 BOR patients and 1,545 controls. LD score regression was used to detect genetic overlap between BOR and these disorders. Single marker analysis revealed no significant association after correction for multiple testing. Genebased analysis yielded two significant genes: DPYD (p=4.42x10-7) and PKP4 (p=8.67x10-7); and gene-set-analysis yielded a significant finding for exocytosis (GO:0006887, pFDR=0.019). Prior studies have implicated DPYD, PKP4 and exocytosis in BIP and SCZ. The most notable finding of the present study was the genetic overlap of BOR with BIP (rg=0.28 [p=2.99x10-3]), SCZ (rg=0.34 [p=4.37x10-5]), and MDD (rg=0.57 [p=1.04x10-3]). Our study is the first to demonstrate that BOR overlaps with BIP, MDD and SCZ on the genetic level. Whether this is confined to transdiagnostic clinical symptoms should be examined in future studies

The German AugUR study: study protocol of a prospective study to investigate chronic diseases in the elderly

Background The majority of patients suffering from chronic health disabilities is beyond 70 years of age. Typical late-onset chronic diseases include those affecting the heart, the kidney, cancer, and conditions of the eye such as age-related macular degeneration. These diseases disable patients for many years and largely compromise autonomy in daily life. Due to challenges in recruiting the elderly, the collection of population-based epidemiological data as a prerequisite to understand associated risk factors and mechanisms is commonly done in the general population within an age-range of 20 to 70 years. Methods/Design We establish the German AugUR study (Age-related diseases: understanding genetic and non-genetic influences - a study at the University of Regensburg), a prospective study in the mobile elderly general population in and around Regensburg in eastern Bavaria. In the long term, we aim to recruit 3,000 persons of Caucasian ethnicity with at least 70 years of age via residents’ registration offices and conduct 3-year follow-ups. The study protocol includes a standardized interview regarding social and life-style factors, medication history, quality-of-life, and existing diagnoses of common diseases. The participants undergo medical examinations for ophthalmological, cardiovascular or diabetes-related conditions, and general measurements of body shape and fitness. The program is particularly tailored for the elderly. Biobanking of whole blood, serum, plasma, and urine is conducted and standard laboratory measurements are performed in fresh samples. Discussion AugUR is specifically designed as a research platform to host studies of late onset diseases. Consequently, this platform will help (1) to unravel the genetic and non-genetic etiology of disease development and progression, (2) to serve as control group of elderly individuals for comparisons with various patient groups, (3) to derive prevalence and incidence data on chronic diseases, and (4) to provide clinical reference parameters for the elderly mobile general population. This data will foster our understanding of disease mechanisms, which may ultimately help to improve prevention, diagnosis, and therapy for frequent chronic diseases. Here we present the baseline study protocol of AugUR

Search for supersymmetry with a dominant R-parity violating LQDbar couplings in e+e- collisions at centre-of-mass energies of 130GeV to 172 GeV

A search for pair-production of supersymmetric particles under the assumption that R-parity is violated via a dominant LQDbar coupling has been performed using the data collected by ALEPH at centre-of-mass energies of 130-172 GeV. The observed candidate events in the data are in agreement with the Standard Model expectation. This result is translated into lower limits on the masses of charginos, neutralinos, sleptons, sneutrinos and squarks. For instance, for m_0=500 GeV/c^2 and tan(beta)=sqrt(2) charginos with masses smaller than 81 GeV/c^2 and neutralinos with masses smaller than 29 GeV/c^2 are excluded at the 95% confidence level for any generation structure of the LQDbar coupling.Comment: 32 pages, 30 figure