21 research outputs found

    Urban road networks -- Spatial networks with universal geometric features? A case study on Germany's largest cities

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    Urban road networks have distinct geometric properties that are partially determined by their (quasi-) two-dimensional structure. In this work, we study these properties for 20 of the largest German cities. We find that the small-scale geometry of all examined road networks is extremely similar. The object-size distributions of road segments and the resulting cellular structures are characterised by heavy tails. As a specific feature, a large degree of rectangularity is observed in all networks, with link angle distributions approximately described by stretched exponential functions. We present a rigorous statistical analysis of the main geometric characteristics and discuss their mutual interrelationships. Our results demonstrate the fundamental importance of cost-efficiency constraints for in time evolution of urban road networks.Comment: 16 pages; 8 figure

    Defining the Critical Hurdles in Cancer Immunotherapy

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    ABSTRACT: Scientific discoveries that provide strong evidence of antitumor effects in preclinical models often encounter significant delays before being tested in patients with cancer. While some of these delays have a scientific basis, others do not. We need to do better. Innovative strategies need to move into early stage clinical trials as quickly as it is safe, and if successful, these therapies should efficiently obtain regulatory approval and widespread clinical application. In late 2009 and 2010 the Society for Immunotherapy of Cancer (SITC), convened an "Immunotherapy Summit" with representatives from immunotherapy organizations representing Europe, Japan, China and North America to discuss collaborations to improve development and delivery of cancer immunotherapy. One of the concepts raised by SITC and defined as critical by all parties was the need to identify hurdles that impede effective translation of cancer immunotherapy. With consensus on these hurdles, international working groups could be developed to make recommendations vetted by the participating organizations. These recommendations could then be considered by regulatory bodies, governmental and private funding agencies, pharmaceutical companies and academic institutions to facilitate changes necessary to accelerate clinical translation of novel immune-based cancer therapies. The critical hurdles identified by representatives of the collaborating organizations, now organized as the World Immunotherapy Council, are presented and discussed in this report. Some of the identified hurdles impede all investigators, others hinder investigators only in certain regions or institutions or are more relevant to specific types of immunotherapy or first-in-humans studies. Each of these hurdles can significantly delay clinical translation of promising advances in immunotherapy yet be overcome to improve outcomes of patients with cancer

    Whole-genome sequencing reveals host factors underlying critical COVID-19

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    Critical COVID-19 is caused by immune-mediated inflammatory lung injury. Host genetic variation influences the development of illness requiring critical care1 or hospitalization2,3,4 after infection with SARS-CoV-2. The GenOMICC (Genetics of Mortality in Critical Care) study enables the comparison of genomes from individuals who are critically ill with those of population controls to find underlying disease mechanisms. Here we use whole-genome sequencing in 7,491 critically ill individuals compared with 48,400 controls to discover and replicate 23 independent variants that significantly predispose to critical COVID-19. We identify 16 new independent associations, including variants within genes that are involved in interferon signalling (IL10RB and PLSCR1), leucocyte differentiation (BCL11A) and blood-type antigen secretor status (FUT2). Using transcriptome-wide association and colocalization to infer the effect of gene expression on disease severity, we find evidence that implicates multiple genes—including reduced expression of a membrane flippase (ATP11A), and increased expression of a mucin (MUC1)—in critical disease. Mendelian randomization provides evidence in support of causal roles for myeloid cell adhesion molecules (SELE, ICAM5 and CD209) and the coagulation factor F8, all of which are potentially druggable targets. Our results are broadly consistent with a multi-component model of COVID-19 pathophysiology, in which at least two distinct mechanisms can predispose to life-threatening disease: failure to control viral replication; or an enhanced tendency towards pulmonary inflammation and intravascular coagulation. We show that comparison between cases of critical illness and population controls is highly efficient for the detection of therapeutically relevant mechanisms of disease

    In vivo paracrine interaction between urokinase and its receptor. Effect on tumor cell invasion

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    Abstract. Numerous studies have linked the production of increased levels of urokinase type plasminogen activator (uPA) with the malignant phenotype. It has also been shown that a specific cell surface receptor can bind uPA through a domain distinct and distant from the proteolytic domain. In an in vivo model of invasion, consisting of experimentally modified chorioallantoic membrane (CAM) of a chick embryo, only cells that concurrently expressed both uPA and a receptor for uPA, and in which the receptor was saturated with uPA, were efficient in invasion. To test whether uPA produced by one cell can, in a paracrine fashion, affect the invasive capacity of a receptorexpressing cell, we transfected LB6 mouse cells with human uPA (LB6[uPA]), or human uPA-recepto

    Nutritional factors influencing milk urea in buffaloes

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    Urea is the primary form in which N is excreted in ruminants. Milk urea (MU) content was introduced as a means to monitor the efficiency of protein utilisation in dairy cattle (Baker et al., 1995; Roseler et al., 1993; Bertoni, 1995). In this study the effect of some nutrition factors on MU content in buffalo herds was analysed in order to examine the possibility that protein nutrition could be monitored by means of milk urea at herd level.......

    Nutritional factors influencing milk urea in buffaloes.

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