Spacetime metric for pedestrian movement

This paper will present a model for pedestrian motion by defining a spacetime metric. This model considers the factors that are effective in the movement of pedestrians (such as obstacles, walls and other pedestrians) by defining a proper metric. In fact, the surrounding environment that affects the motion of pedestrians changes the flat(Euclidean) spacetime metric and, therefore, the shortest possible path to their destination. This change is such that pedestrians have a different feeling of time at any point and moment in the environment. Based on this feeling, they adjust their route to the destination so that they travel the shortest possible route in curved spacetime, which follows a geodesic. The contributions are :1. Defining spacetime metric for pedestrian movement.2. Visualizing the spacetime geometry for several timesteps.3. Introducing a parameter called the time factor and its physical meaning in terms of the pedestrian feeling of time. According to this paper formulation, pedestrians feel time differently at each position and moment, and the time factor measures this feeling of time. 4. Proposing a simple model with differential equations suitable for data assimilation methods while preserving the essential feature of collision avoidance behaviour

stress analysis of composite adhesive bonded joints under incipient failure conditions

Abstract Composite structures with their remarkable properties often require assembling different components and repairing the damaged regions by employing mechanical or adhesive bonding joints. Among the bonding techniques, adhesive bonding is considered the most diffused and efficient method. Analysis of stress distribution that develops in the joint is a crucial field of research to put effort with the aim to develop engineering strength criteria. Once an adhesive bonded joint is subjected to the axial tensile load, shear and peel stress intensification takes place at the ends of the overlap. With regard to the literature, it can be concluded that there are few reliable predicting tools for brittle adhesives, for which failure usually initiates at the edge of the bonding area and propagates through the interface region. The aim of this paper is an investigation on stress field in single-lap joint (SLJ) and scarf-lap joint (ScJ) under the tensile loading. A two-dimensional numerical analysis by employing Finite Element Method (FEM) and a developed analytical solution were implemented to realize the correlation of the results. Furthermore, a comparison between possible failure criteria was performed by using FE results. Adherend thickness, overlap length, and scarf angle were considered as the joint geometry parameters. Effects of these parameters on the fracture behaviour of bonded joints were evaluated

A rare case of centronuclear myopathy with DNM2 mutation: genotype–phenotype correlation

Centronuclear myopathy (CNM) is a group of rare genetic muscle disorders characterized by muscle fibers with centrally located nuclei. The most common forms of CNM have been attributed to X-linked recessive mutations in the MTM1 gene; autosomal-dominant mutations in the DNM2 gene-encoding dynamin-2, the BIN1 gene; and autosomal-recessive mutations in BIN1, RYR1, and TTN genes. Dominant CNM due to DNM2 mutations usually follows a mild clinical course with the onset in adolescence. Currently, around 35 mutations of the DNM2 gene have been identified in CNM; however, the underlying molecular mechanism of DNM2 mutation in the pathology of CNM remains elusive, and the standard clinical characteristics have not yet been defined. Here, we describe the case of a 17-year-old female who presented with proximal muscle weakness along with congenital anomalous pulmonary venous connection (which has not been described in previous cases of CNM), scoliosis, and lung disease without a significant family history. Her creatine kinase level was normal. Histology, special stains, and electron microscope findings on her skeletal muscle biopsy showed CNM with the characteristic features of a DNM2 mutation, which was later confirmed by next-generation sequencing. This case expands the known clinical and pathological findings of CNM with DNM2 gene mutatio

The Effect of the Cash Flow Sensitivity to Institutional Ownership on the Level of the Companies’ Cash Holding in Iran

The main purpose of this study is to study the influence of the cash flow sensitivity to the institutional ownership on the level of cash holding among listed companies in Tehran Stock Exchange. Accordingly, to test the research hypotheses, financial data of 69 companies which published their financial statements during a five years period 2008-2012, were selected by using the systematic classified sampling. The variation of cash in the current year to the previous year was used as cash flow and level of the cash holding upon the past study of Bao et al. (2012). The selected approach was based on the mixing of the modulated data and the regression method of the merged least squares. The results from the research hypothesis test shows that the sensitivity of the cash flow to the institutional ownership has a reverse effect on the variations of the level of cash holding

Hinted Dictionaries: Efficient Functional Ordered Sets and Maps

This paper introduces hinted dictionaries for expressing efficient ordered sets and maps functionally. As opposed to the traditional ordered dictionaries with logarithmic operations, hinted dictionaries can achieve better performance by using cursor-like objects referred to as hints. Hinted dictionaries unify the interfaces of imperative ordered dictionaries (e.g., C++ maps) and functional ones (e.g., Adams\u27 sets). We show that such dictionaries can use sorted arrays, unbalanced trees, and balanced trees as their underlying representations. Throughout the paper, we use Scala to present the different components of hinted dictionaries. We also provide a C++ implementation to evaluate the effectiveness of hinted dictionaries. Hinted dictionaries provide superior performance for set-set operations in comparison with the standard library of C++. Also, they show a competitive performance in comparison with the SciPy library for sparse vector operations

Effects of external focus of attention on learning static balance among girls with ADHD

Summary Study aim: The purpose of this study was to examine the effects of adopting an external focus of attention on motor learning among girls with ADHD aged seven and eleven years.Material and methods: Twenty-four seven-year-old and 24 eleven-year-old female children with symptoms of ADHD were randomly assigned to groups receiving either external focus of attention (EXT) instructions or internal focus of attention (INT) instructions, making four experimental groups: EXT-7, INT-7, EXT-11, and INT-11. Participants performed a pretest followed by five training blocks under an external or internal instruction and were then given a retention test one day later. After training, we employed a manipulation check to verify the children’s type and intensity of focus.Results: Adopting an external focus of attention, compared to an internal focus of attention, led to better motor learning among girls with ADHD (F1, 44 = 5.08, p = 0.029, η2 = 0.10). In addition, adopting an external focus of attention reduced the children’s tendency to focus on self. Older children performed better than younger children in balance time (F1, 44 = 16.10, p < 0.001, η2 = 0.26).Conclusions: Our results indicate that propositions of the OPTIMAL theory can be extended to children with ADHD

Filogenetska analiza gena za hemaglutinin podtipa H9N2 virusa influence ptica izdvojenih iz tovnih pilića u Iranu.

In the present study, the genetic variations were examined of hemagglutinin genes of 4 recent H9N2 subtype avian influenza viruses isolated in the Tehran province of Iran. These hemagglutinin genes were amplified and sequenced in order to compare these viruses with the previous isolates from Iran and some other countries from all over the world. The full length hemagglutinin genes of 112 H9N2 avian influenza strains isolated from chickens, and also migratory birds from all over the world, including 68 strains isolated in Iran during 1998-2012, were genetically analyzed. The amino acids in the hemagglutinin cleavage site of the all 4 recent isolates possessed a PAKSSR/GL motif, which is a different motif when compared with the predominant PARSSR/GL motif in the hemagglutinin of the Iranian H9N2 strains isolated before 2010. All 4 recent isolates possessed histidine, alanin, leucine and isoleucine at positions 183, 190, 226 and 227 respectively, which are the key residues in receptor-binding sites. Genetic and phylogenetic analysis of the hemagglutinin genes showed that recent H9N2 strains isolated from chickens in Iran during 2010-2012, formed a distinct subgroup of the previous strains. Recent changes in the H9N2 viruses may be the result of the widespread circulation of these viruses in recent years. This may be due to the lack of adequate surveillance and control programs, such as vaccination and quarantine. Hence, it is highly recommended that continuous surveillance programs and genetic analysis of ongoing changes to H9N2 should be considered.Istražene su inačice gena za hemaglutinin četiriju nedavno izdvojenih izolata podtipa H9N2 virusa influence ptica na području Teherana u Iranu. Geni su umnoženi i sekvencirani s ciljem da se obilježja virusa usporede s prijašnjim izolatima iz Irana i nekih drugih zemalja u svijetu. Analizirani su geni za hemaglutinin u punoj dužini od 112 izolata H9N2 iz pilića i ptica selica iz cijelog svijeta, uključujući i 68 izolata iz Irana od 1998. do 2012. Aminokiselinski sastav na mjestu cijepanja hemaglutinina svih četiriju nedavno izdvojenih izolata sadržavao je PAKSSR/GL motiv, koji je bio različit u usporedbi s prevladavajućim PARSSR/GL u hemaglutininu iranskih sojeva H9N2 izdvojenih prije 2010. Sva četiri izolata posjedovala su histidin, alanin, leucin i izoleucin na pozicijama 183, 190, 226 i 227, koje su ključne za vezanje na receptore. Genetska i filogenetska analiza gena za hemaglutinin pokazala je da izolati H9N2 iz pilića u Iranu izdvojeni od 2010. do 2012. čine posebnu i različitu podskupinu od prijašnjih izolata. Dokazane izmjene tih izolata mogle bi biti uzrok njihova širenja posljednjih godina. To se moglo dogoditi zbog nedostatka odgovarajućeg programa nadzora i kontrole koji bi obuhvaćali cijepljenje i karantenu. Stoga se posebice preporučuje provođenje programa genetske analize te trajnog praćenja trenutnih promjena podtipa H9N2

(sub)GeV Dark Matter in the U(1)XU(1)_X Higgs Portal Model

In this research we consider a $U(1)_X$ gauge boson acting as a dark matter candidate. The vector dark matter (DM) gets mass when a complex singlet scalar breaks the gauge symmetry spontaneously, adding a second Higgs boson to the spectra. The dark matter candidates communicate with the SM particles via a scalar-Higgs portal. In this work, we concentrate on the masses of the vector dark matter and the scalar mediator below 10 GeV, aka light dark matter. Although we assume thermal freeze-out for the vector DM using the zero-moment of the full Boltzmann equation to calculate the relic abundance, we explore the effects of the second-moment when the vector DM annihilates resonantly. As typically light DM is highly sensitive to CMB bounds, we focus on two thermal mechanisms which alleviate this bound: dark matter annihilation via forbidden channels and near a pole. Other bounds from colliders, thermalization conditions, beam-dump experiments, and astrophysical observations are imposed. Taking into account all the bounds including the direct detection upper limits, the viable space is achieved