Network centrality: an introduction

Centrality is a key property of complex networks that influences the behavior of dynamical processes, like synchronization and epidemic spreading, and can bring important information about the organization of complex systems, like our brain and society. There are many metrics to quantify the node centrality in networks. Here, we review the main centrality measures and discuss their main features and limitations. The influence of network centrality on epidemic spreading and synchronization is also pointed out in this chapter. Moreover, we present the application of centrality measures to understand the function of complex systems, including biological and cortical networks. Finally, we discuss some perspectives and challenges to generalize centrality measures for multilayer and temporal networks.Comment: Book Chapter in "From nonlinear dynamics to complex systems: A Mathematical modeling approach" by Springe

Matrix gla protein in xenopus laevis: molecular cloning, tissue distribution, and evolutionary considerations

Matrix Gla protein (MGP) belongs to the family of vitamin K-dependent, Gla-containing proteins and in higher vertebrates, is found in the extracellular matrix of mineralized tissues and soft tissues. MGP synthesis is highly regulated at the transcription and posttranscription levels and is now known to be involved in the regulation of extracellular matrix calcification and maintenance of cartilage and soft tissue integrity during growth and development. However, its mode of action at the molecular level remains unknown. Because there is a large degree of conservation between amino,acid sequences of shark and human MGP, the function of MGP probably has been conserved throughout evolution. Given the complexity of the mammalian system, the study of MGP in a lower vertebrate might be advantageous to relate the onset of MGP expression with specific events during development. Toward this goal, MGP was purified from Xenopus long bones and its N-terminal amino acid sequence was determined and used to clone the Xenopus MGP complementary DNA (cDNA) by a mixture of reverse-transcription (RT)- and 5'- rapid amplification of cDNA ends (RACE)-polymerase chain reaction (PCR). MGP messenger RNA (mRNA) was present in all tissues analyzed although predominantly expressed in Xenopus bone and heart and its presence was detected early in development at the onset of chondrocranium development and long before the appearance of the first calcified structures and metamorphosis. These results show that in this system, as in mammals, MGP may be required to delay or prevent mineralization of cartilage and soft tissues during the early stages of development and indicate that Xenopus is an adequate model organism to further study MGP function during growth and development.NATO/CRG940751/SA5.2.05, Praxis XXI/BIA 469/94, (NIH; grant AR 25921) (Praxis XXI/BPD/18816) (Praxis XXI/BICJ-2985

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

Measurement of the mass difference m(D-s(+))-m(D+) at CDF II

We present a measurement of the mass difference m(D-s(+))-m(D+), where both the D-s(+) and D+ are reconstructed in the phipi(+) decay channel. This measurement uses 11.6 pb(-1) of data collected by CDF II using the new displaced-track trigger. The mass difference is found to be m(D-s(+))-m(D+)=99.41+/-0.38(stat)+/-0.21(syst) MeV/c(2)

The prototype of the MICE Electron\u2013Muon Ranger: Design, construction and test

Muon Ionization Cooling Experiment (MICE) and its goal to demonstrate the feasibility of ionization cooling represent the first step toward a neutrino factory. Muons in MICE are produced by pions which derive from the interaction of protons with a target. Muons being short lived particles, a special cooling procedure has to be developed, to be able to reduce the emittance quickly. MICE intends to measure the emittance value with a 0.1% accuracy before and after the cooling element; thus a detector able to reconstruct and identify individual particles is required. The presence of electrons due to muon decay introduces a systematic error on the emittance and cooling measurements. For this reason a particle identification system is being developed based on a totally active scintillator tracker/calorimeter (Electron\u2013Muon Ranger (EMR)). The detector consists of 40 planes of extruded scintillator bars 1 m long; the bars are read out with 0.8 mm WLS fibers coupled to multianode photomultipliers. The readout segmentation will be chosen accordingly to the rate (600 good muons per 1 ms spill every 1 s). This paper describes the design, construction and test at the CERN PS T9-line of the first small size prototype of the EMR with full analog readout, consisting of eight layers (4 x and 4 y) with 10 bars 19 cm long each