• CONCLUSIONS--There was strong evidence of joint spatial-temporal clustering, with an excess of pairs separated by very short time and distance intervals. (
  • Kulldorff M, Nagarwalla N. Spatial disease clusters: Detection and Inference. (
  • Border Analysis for Spatial Clusters. (

scan statistic

  • Kulldorff M, Athas W, Feuer E, Miller B, Key C. Evaluating cluster alarms: A space-time scan statistic and brain cancer in Los Alamos. (
  • Kulldorff M. Prospective time-periodic geographical disease surveillance using a scan statistic. (
  • Kulldorff M, Heffernan R, Hartman J, Assunção RM, Mostashari F. A space-time permutation scan statistic for the early detection of disease outbreaks. (


  • Galaxies can also have satellites in the form of dwarf galaxies and globular clusters. (
  • It was aimed at the current location of the globular star cluster Messier 13 some 25,000 light years away. (


  • Leukaemia clusters in Great Britain. (
  • STUDY OBJECTIVE--The aim was to test a large set of childhood leukaemia and lymphoma registrations for the presence of clusters in space and in time. (


  • Klassen A, Kulldorff M, Curriero F. Geographical clustering of prostate cancer grade and stage at diagnosis, before and after adjustment for risk factors. (
  • The knowledge about near repeats bases on the experience that crimes of the below mentioned categories are often not committed only once, but several times within a close geographical and temporal context, the so-called spatiotemporal proximity (see also Crime Contagion Models). (
  • The software analyses this data and predicts future crimes in a geographical radius of 250m and in a time window of between 24 hours and 7 days. (


  • The result of such synapse mapping analysed with a newly developed algorithm was clear: The synapses of pyramidal cells form clusters consisting of 4 to 14 synapses arranged within an area of less than 30 micrometres along the dendrite. (
  • In the theory of cluster analysis, the nearest-neighbor chain algorithm is an algorithm that can speed up several methods for agglomerative hierarchical clustering. (
  • The cluster distances for which the nearest-neighbor chain algorithm works are called reducible and are characterized by a simple inequality among certain cluster distances. (
  • The main idea of the algorithm is to find pairs of clusters to merge by following paths in the nearest neighbor graph of the clusters. (
  • Every such path will eventually terminate at a pair of clusters that are nearest neighbors of each other, and the algorithm chooses that pair of clusters as the pair to merge. (
  • By following paths in this way, the nearest-neighbor chain algorithm merges its clusters in a different order than methods that always find and merge the closest pair of clusters. (
  • The nearest-neighbor chain algorithm constructs a clustering in time proportional to the square of the number of points to be clustered. (
  • The algorithm uses an amount of memory proportional to the number of points, when it is used for clustering methods such as Ward's method that allow constant-time calculation of the distance between clusters. (
  • Given this distance between clusters, a hierarchical clustering may be defined by a greedy algorithm that initially places each point in its own single-point cluster and then repeatedly forms a new cluster by merging the closest pair of clusters. (
  • The bottleneck of this greedy algorithm is the subproblem of finding which two clusters to merge in each step. (


  • The resultant stripped material will eventually be dispersed throughout the core of the Coma Cluster, where it will fuel the intergalactic populations of stars and star clusters. (


  • Residential clusters of non-communicable diseases are a source of enduring public concern, and at times, controversy. (
  • Many problems in data analysis concern clustering, grouping data items into clusters of closely related items. (


  • A statistically significant excess of cases of a disease, occurring within a limited space-time continuum. (
  • Several potential artefacts were considered and excluded, but the possibility remained that clustered detections might be triggered by haematological examinations undertaken for some communicable disease. (
  • Kleinman K, Lazarus R, Platt R. A generalized linear mixed models approach for detecting incident clusters of disease in small areas, with an application to biological terrorism. (
  • Moreover, if associations between environmental factors and the disease exist, it is relevant to establish whether increasing temporal trends are occurring cross-sectionally, affecting all age-groups at the same point in time (period effects), or longitudinally, affecting all age-groups from the same birth cohort (cohort effects) ( 16 ). (
  • Many clusters reported to public health agencies by concerned citizens are accompanied by expectations that investigations will uncover a cause of disease. (
  • While goals, methods and conclusions of cluster studies are debated in the scientific literature and popular press, investigations of reported residential clusters rarely provide definitive answers about disease etiology. (


  • Earthquake prediction is a branch of the science of seismology concerned with the specification of the time, location, and magnitude of future earthquakes within stated limits, and particularly "the determination of parameters for the next strong earthquake to occur in a region. (
  • While such statistics are not satisfactory for purposes of prediction (giving ten to twenty false alarms for each successful prediction) they will skew the results of any analysis that assumes that earthquakes occur randomly in time, for example, as realized from a Poisson process. (
  • 99..729K, doi:10.1029/93JB01556 Santoyo, M. A (2005), "Space-Time Clustering of Large Thrust Earthquakes along the Mexican Subduction Zone: An Evidence of Source Stress Interaction" (PDF), Bulletin of the Seismological Society of America, Seismological Society of America, 95 (5): 1856, Bibcode:2005BuSSA. (


  • The Cluster of Excellence is with scientists from the fields of quantum optics, laser physics, solid state physics, gravitational physics, theoretical physics and geodesy interdisciplinary orientated. (
  • The other three techniques (BAO, galaxy clusters, and weak lensing) used by the Dark Energy Survey allow scientists to understand simultaneously the expansion of the universe and the evolution of the dark matter density field perturbations. (
  • Scientists at the Max Planck Institute of Neurobiology in Martinsried have now shown for the first time that contact points between specific neuron types are clustered in groups on the target neuron. (
  • For the first time, scientists have precisely measured the effective electrical charge of a single molecule in solution. (
  • MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network. (
  • Now ESA's Cluster mission is showing scientists how to understand this emission and, in the future, search for alien worlds by listening for their sounds. (
  • Consisting of four nearly identical spacecraft flying in formation, Cluster allowed the scientists to precisely time when the AKR washed over each of the satellites. (


  • Clustering occurs in both space and time. (
  • When gene duplication occurs to produce a gene cluster, one or multiple genes may be duplicated at once. (


  • Messier object M26, a magnitude 9.5 open cluster in the constellation Scutum. (


  • The Dark Energy Survey investigates the dynamics and large scale structure of the Universe using four probes: Type Ia supernovae, baryon acoustic oscillations (BAO), the number of galaxy clusters, and weak gravitational lensing. (
  • These perturbations were intrinsically tied to the formation of galaxies and galaxy clusters. (
  • This is a very important property for the observation of very distant sources, like Type IA supernovae or galaxy cluster, because the expansion of the universe shifts the photons emitted from a given source towards redder wavelengths. (
  • Some of the primary working groups are: the weak lensing working group, the galaxy clusters working group, the large-scale structure working group, the supernova working group, the galaxy evolution working group, and the strong lensing working group. (
  • A long-exposure Hubble Space Telescope image shows a majestic face-on spiral galaxy located deep within the Coma Cluster of galaxies, which lies 320 million light-years away in the northern constellation Coma Berenices. (
  • It continues to transform galaxies at the present epoch, due to the interactions of close-proximity galaxy systems within the dense cluster. (


  • Space-Time Clustering of Childhood Leukemia: Evidence of an Association with ETV6-RUNX1 (TEL-AML1) Fusion. (
  • Increased incidence rates but no space-time clustering of childhood astrocytoma in Sweden, 1973-1992: a population-based study of pediatric brain tumors. (
  • Time trends and characteristics of childhood cancer among children age 0-14 in Shanghai. (


  • Both of these kinds of analysis can be seen, for instance, in the application of hierarchical clustering to biological taxonomy. (


  • Further, it is inherently difficult to study a cluster for diseases with complex etiology and long latency (e.g., most cancers). (


  • DESIGN--The study was a space-time cluster analysis. (
  • I have a special interest in methods and analysis of clustering of chronic diseases. (
  • Age-period-cohort analysis shows that the variation over time has a linear component that cannot be ascribed to either the calendar period or the birth cohort. (
  • Hierarchical clustering is a version of cluster analysis in which the clusters form a hierarchy or tree-like structure rather than a strict partition of the data items. (
  • In some cases, this type of clustering may be performed as a way of performing cluster analysis at multiple different scales simultaneously. (


  • Gravitational collapse enhances these initial fluctuation as baryons fall into the gravitational potential field of more dense regions of space to form galaxies. (
  • The Coma Cluster is home to almost 1,000 galaxies, making it one of the densest collections of galaxies in the nearby universe. (
  • Galaxies in this cluster are so densely packed that they undergo frequent interactions and collisions. (
  • Merging is more likely to occur in the center of the cluster where the density of galaxies is higher, giving rise to more elliptical galaxies. (
  • Galaxies are organized into groups and clusters, often within larger superclusters, that are strung along great filaments between nearly empty voids, forming a web that spans the observable universe. (


  • The Cluster of Excellence QUEST - Centre for Quantum Engineering and Space-Time Research has been funded since November 2007 in the framework of the German Universities Excellence Initiative of the federal and state governments of Germany. (
  • The key research areas of the cluster are the quantum engineering and the space-time research. (
  • In the cluster quantum effects for the production of new measurement technologies are being explored. (


  • The existence of these clusters suggests that the synapses interact with each other to control the strength of the combined signal," explains Onur Gökçe, author of the study. (
  • These are silhouetted against glowing newborn star clusters and iridescent pink clouds of hydrogen, the existence of which indicates ongoing star formation. (


  • 1965 - Venera program: The Soviet Union launches the Venera 3 space probe toward Venus, which will be the first spacecraft to reach the surface of another planet. (


  • however, the resulting protein of each gene is distinctive from the resulting protein of another gene within the cluster. (


  • Exposure to outdoor air pollutants primarily leads to increased exacerbations, sometimes manifested as asthma clusters. (
  • Clinicians should be alert for space-time clusters of asthma exacerbations in the community, because these clusters may suggest a modifiable point-source exposure. (
  • This natural-color Hubble image, which combines data obtained in 2006, 2007, and 2009 from the Wide Field Planetary Camera 2 and the Advanced Camera for Surveys, required 28 hours of exposure time. (


  • These are methods that take a collection of points as input, and create a hierarchy of clusters of points by repeatedly merging pairs of smaller clusters to form larger clusters. (
  • However, for some other clustering methods it uses a larger amount of memory in an auxiliary data structure with which it keeps track of the distances between pairs of clusters. (
  • Next, the dissimilarity function is extended from pairs of points to pairs of clusters. (
  • Known methods for repeatedly finding the closest pair of clusters in a dynamic set of clusters either require superlinear space to maintain a data structure that can find closest pairs quickly, or they take greater than linear time to find each closest pair. (
  • A gene cluster is a group of two or more genes found within an organism's DNA that encode for similar polypeptides, or proteins, which collectively share a generalized function and are often located within a few thousand base pairs of each other. (


  • In this application, different living things are grouped into clusters at different scales or levels of similarity (species, genus, family, etc). (
  • Species who have gene clusters have a selective evolutionary advantage because natural selection must keep the genes together. (


  • From the locally recorded time intervals between the arrival of the S wave and the P wave (S−P times) and from the felt intensities, it is suggested that the rupture zone of this earthquake was larger than the 1973 earthquake and may have extended into the rupture zone of the 1985 Michoacán earthquake. (


  • The total cost of construction (around US$20 million) and operation as well as the telescope time use will be 50% shared by both countries. (
  • Space Telescope Science Institute, Baltimore, Md. (
  • The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. (
  • NASA's Goddard Space Flight Center manages the telescope. (
  • The Space Telescope Science Institute (STScI) conducts Hubble science operations. (


  • 1. Space-time interactions. (


  • This result was only possible because of the Cluster mission's four spacecraft," says Mutel. (


  • V. Max-Planck Institute for Gravitational Physics (Albert Einstein Institute, Hannover) Gravitational wave detector GEO600 Physikalisch-Technische Bundesanstalt, Braunschweig/Germany Center for Applied Space Technology and Microgravity (ZARM), Bremen/Germany The Wissenschaftsrat had 2010 recommended to build a new research building at Leibniz Universität Hanover, the Hanover Institute of Technology, HiTec shortly. (
  • NGC 4911 and other spirals near the center of the cluster are being transformed by the gravitational tug of their neighbors. (


  • These gene clusters include the Hox gene cluster, the human β-globin gene cluster, and four clustered human growth hormone (hGH)/chorionic somaomammotropin genes. (


  • however, rather than the Hox cluster and the ParaHox cluster resulting from a cluster containing three genes, the Hox cluster and ParaHox cluster were as a result of single gene tandem duplication, identical genes found adjacent on the same chromosome. (


  • Point clusters are clusters of suicides in both time and space, and have been linked to direct social learning from nearby individuals. (


  • these all work by repeatedly merging the closest two clusters but use different definitions of the distance between clusters. (
  • Different clustering methods perform this extension in different ways. (
  • Genes found in a gene cluster may be observed near one another on the same chromosome or on different, but homologous chromosomes. (
  • however, over a long, evolutionary time period, the genetic information in the duplicated copy may undergo additional and drastic mutations in which the proteins of the duplicated gene served a different role than those of the original essential gene. (


  • Star clusters: basic galactic building blocks throughout time and space, Proceedings of the International Astronomical Union, IAU Symposium. (


  • Prediction can be further distinguished from earthquake warning systems, which upon detection of an earthquake, provide a real-time warning of seconds to neighboring regions that might be affected. (


  • Equipped with in-situ techniques in combination with Transmission electron microscopy (TEM), Scanning electron microscopy (SEM), and micro-diffraction methods, this nanomechanical testing method can give us rich detail in nanoscale plasticity instabilities in real time. (
  • For instance, in the single-linkage clustering method, the distance between two clusters is defined to be the minimum distance between any two points from each cluster. (


  • The realization that environmental exposures could lead to asthma attacks has its origins in studies of clusters of asthma. (
  • One of the first studies to document the relationship between air pollution and asthma was an investigation of an asthma cluster in Ohio. (
  • Few studies have documented expected time to return to athletic participation after stress fractures in elite athletes. (
  • Stack analyzed the results from 42 studies and found that those measuring the effect of a celebrity suicide story were 14.3 times more likely to find a copycat effect than studies that did not. (


  • The size of gene clusters can vary significantly, from a few genes to several hundred genes. (
  • Hox gene clusters, ranging in various sizes, are found among several phyla. (


  • Historically, four models have been proposed for the formation and persistence of gene clusters. (


  • In agglomerative clustering methods, the input also includes a distance function defined on the points, or a numerical measure of their dissimilarity. (


  • At this level, the resulting fundamental components are the stars, which are typically assembled in clusters from the various condensing nebulae. (


  • Much of what we now know about the relation between outdoor air exposures and asthma came to light as a result of asthma clusters in communities. (
  • It postulates that gene clusters were formed as a result of gene duplication and divergence. (
  • Conserved gene clusters, such as Hox and the human β-globin gene cluster, may be formed as a result of the process of gene duplication and divergence. (
  • As its name indicates, the two gene model gave rise to the Hox cluster and the ParaHox cluster as a result of the ProtoHox cluster which contained only two genes. (


  • The input to a clustering problem consists of a set of points. (
  • A cluster is any proper subset of the points, and a hierarchical clustering is a maximal family of clusters with the property that any two clusters in the family are either nested or disjoint. (
  • the clusters of the clustering are the sets of points in subtrees descending from each node of the tree. (


  • At this time, however, the effectiveness of many primary prevention strategies is unknown. (
  • However, despite that difference, it always generates the same hierarchy of clusters. (
  • However, unlike the distances in a metric space, it is not required to satisfy the triangle inequality. (
  • however, models exist suggesting that the duplicated Protohox cluster originally contained four, three, or two genes. (


  • German Research Foundation: List of current Clusters of Excellence. (


  • 16 - 19 Specific outdoor air pollutants linked to clusters of asthma are described in the following paragraphs. (


  • g., a case-control study in which dioxins are measured in biologic tissues) before clusters of soft-tissue sarcoma and non-Hodgkin's lymphoma are ascribed to dioxin released by the municipal solid waste incinerator. (


  • Multilevel (random intercept) Poisson regression models were used to model the effects of sex, age, calendar time, and birth cohorts on temporal trends, taking into account the registry-level variance component. (


  • Correspondingly, authorities which use Precobs, do not have to deploy staff for the time-consuming research for near repeat crimes or burglary series anymore. (


  • In the four gene model, the ProtoHox cluster contained four genes which resulted in two twin clusters: the Hox cluster and the ParaHox cluster. (