The irreducible vectors of a lattice:Some theory and applications

The main idea behind lattice sieving algorithms is to reduce a sufficiently large number of lattice vectors with each other so that a set of short enough vectors is obtained. It is therefore natural to study vectors which cannot be reduced. In this work we give a concrete definition of an irreducible vector and study the properties of the set of all such vectors. We show that the set of irreducible vectors is a subset of the set of Voronoi relevant vectors and study its properties. For extremal lattices this set may contain as many as 2^n vectors, which leads us to define the notion of a complete system of irreducible vectors, whose size can be upperbounded by the kissing number. One of our main results shows thatmodified heuristic sieving algorithms heuristically approximate such a set (modulo sign). We provide experiments in low dimensions which support this theory. Finally we give some applications of this set in the study of lattice problems such as SVP, SIVP and CVPP. The introduced notions, as well as various results derived along the way, may provide further insights into lattice algorithms and motivate new research into understanding these algorithms better

So far, yet so close: α-Catenin dimers help migrating cells get together

Epithelial cells in tissues use their actin cytoskeletons to stick together, whereas unattached cells make active plasma membrane protrusions to migrate. In this issue, Wood et al. (2017. J. Cell Biol. https://doi.org/10.1083/jcb.201612006) show that the junction component α-catenin is critical in freely moving cells to promote adhesion and migration

Qualitative Methods of Road Traffic Crash Research in Low- and Middle-income Countries: A Review

Road traffic crashes are rapidly becoming one of the leading causes of injury and death globally. It is predicted that by 2030 crashes will become the fourth leading cause of disability-adjusted life years (DALYs) (Mathers & Loncar, [11]) and the seventh leading global cause of death (World Health Organization [WHO], [26]). The global death toll due to crashes has already escalated by 46% over the past two decades (The World Bank, [21]). Low- and middle-income countries (LMICs) are acutely affected by this \u27hidden epidemic\u27 (Balch, [ 1]). Ninety per cent of the world\u27s crash-related deaths occur in LMICs where only 54% of its motor vehicles are registered (WHO, [25]). Furthermore, the economic toll of crashes in LMICs is concerning because nearly one half of all health care expenditures in LMICs is used to treat injuries related to motor vehicle crashes (Zakeri & Nosratnejad, [28]). This epidemic deserves urgent attention (Lin, [10]). Research on the epidemiology of crash problems in LMICs is increasing but these research efforts predominantly report statistics. There is a paucity of qualitative research that could help to explain the statistics. Qualitative exploration has the potential to enhance crash research by describing and explicating the contexts and social processes surrounding crashes, such as the antecedents, the environments in which crashes occur and injuries are produced, and the behaviours of people which make crashes more likely (Roberts, [14]; Rothe, [16]). Qualitative research methods can spark and mobilize the ideas and efforts of affected community members, thereby optimizing crash prevention interventions. Additionally, incorporating local citizens\u27 perspectives on the nature, causes and potential solutions of traffic problems in their locale increases the likelihood that proposed solutions will be effective, wanted and beneficial (Roberts, Smith, & Bryce, [15]). This article will review the literature to assess the extent to which qualitative methods have been implemented to research road traffic crashes in LMICs and to inform future methodological decision-making

Networks among agricultural stakeholders in the southwestern highlands of Uganda

The aim of this study was to explore the interactions that exist among agricultural stakeholders in the southwestern highlands of Uganda as a way of identifying opportunities and gaps for operation of Innovation Platforms (IPs) under the proof of concept of Integrated Agricultural Research for Development (IAR4D) research project. The specific objectives were to (i) characterize the agricultural stakeholders in the study sites (ii) determine the nature, diversity and relative importance of horizontal and vertical networks that exist among stakeholders in the Southwestern Highlands of Uganda. Data were collected from both stakeholder analysis and household interviews in Kabale and Kisoro Districts. Results show that extension staff, local governments and farmer groups accounted for approximately 75% of all categories of stakeholders in the area. Most of these organizations started after 10 to 15 years ago following the return of relative political stability in Uganda. Generally, stakeholder interactions in site with limited ARD intervention are more limited compared to their high-intervention counterparts. Sites with “good” market access have more institutions operating there but majority are isolated from each other. At household level, an individual household has networks with approximately two different organizations most of which are farmer groups or credit associations. The greatest proportion of horizontal networks that a household has is with fellow farmers. In order to make the value chain complete, establishment of IPs should pay special attention to including the private sector such as input and produce dealers. Facilitating IP actors to identify critical challenges and opportunities, and effectively articulate them will ensure cohesion. It is also critical to periodically monitor and evaluate stakeholders in terms of the quality of the networks to minimize conflict situations

Palliative thoracic radiotherapy in lung cancer: An American Society for Radiation Oncology evidence-based clinical practice guideline

AbstractPurposeTo provide guidance to physicians and patients with regard to the use of external beam radiotherapy, endobronchial brachytherapy, and concurrent chemotherapy in the setting of palliative thoracic treatment for lung cancer, based on available evidence complemented by expert opinion.Methods and MaterialsA Task Force authorized by the American Society for Radiation Oncology (ASTRO) Board of Directors synthesized and assessed evidence from 3 systematic reviews on the following topics: (1) dose fractionation in thoracic external beam radiotherapy (EBRT); (2) clinical utility of initial and salvage endobronchial brachytherapy (EBB); and (3) use of concurrent chemotherapy (CC) with palliative thoracic radiotherapy. Practice guideline recommendations were produced and are contained herein.ResultsStudies suggest that higher dose/fractionation palliative EBRT regimens (eg, 30 Gy/10 fraction equivalent or greater) are associated with modest improvements in survival and total symptom score, particularly in patients with good performance status. As these improvements are associated with an increase in esophageal toxicity, various shorter EBRT dose/fractionation schedules (eg, 20 Gy in 5 fractions, 17 Gy in 2 weekly fractions, 10 Gy in 1 fraction), which provide good symptomatic relief with fewer side effects, can be used for patients requesting a shorter treatment course and/or in those with a poor performance status. No defined role for EBB in the routine initial palliative treatment of chest disease has been demonstrated; however, EBB can be a reasonable option for the palliation of endobronchial lesions causing obstructive symptomatology including lung collapse, or for hemoptysis after EBRT failure. The integration of concurrent chemotherapy with palliative intent/fractionated radiotherapy is not currently supported by the medical literature.ConclusionThis Guideline is intended to serve as a guide for the use of EBRT, EBB, and CC in thoracic palliation of lung cancer outside the clinical trial setting. Further prospective clinical investigations with relevant palliative endpoints into the respective roles of EBB and CC/targeted therapy in the thoracic palliation of lung cancer are warranted, given the current state of the medical literature in these areas

On User Behaviour Adaptation Under Interface Change

Different interfaces allow a user to achieve the same end goal through different action sequences, e.g., command lines vs. drop down menus. Interface efficiency can be described in terms of a cost incurred, e.g., time taken, by the user in typical tasks. Realistic users arrive at evaluations of efficiency, hence making choices about which interface to use, over time, based on trial and error experience. Their choices are also determined by prior experience, which determines how much learning time is required. These factors have substantial effect on the adoption of new interfaces. In this paper, we aim at understanding how users adapt under interface change, how much time it takes them to learn to interact optimally with an interface, and how this learning could be expedited through intermediate interfaces. We present results from a series o

Chelator free gallium-68 radiolabelling of silica coated iron oxide nanorods via surface interactions

The commercial availability of combined magnetic resonance imaging (MRI)/positron emission tomography (PET) scanners for clinical use has increased demand for easily prepared agents which offer signal or contrast in both modalities. Herein we describe a new class of silica coated iron–oxide nanorods (NRs) coated with polyethylene glycol (PEG) and/or a tetraazamacrocyclic chelator (DO3A). Studies of the coated NRs validate their composition and confirm their properties as in vivo T₂ MRI contrast agents. Radiolabelling studies with the positron emitting radioisotope gallium-68 (t1/2 = 68 min) demonstrate that, in the presence of the silica coating, the macrocyclic chelator was not required for preparation of highly stable radiometal-NR constructs. In vivo PET-CT and MR imaging studies show the expected high liver uptake of gallium-68 radiolabelled nanorods with no significant release of gallium-68 metal ions, validating our innovation to provide a novel simple method for labelling of iron oxide NRs with a radiometal in the absence of a chelating unit that can be used for high sensitivity liver imaging

Increased transcription of transglutaminase 1 mediates neuronal death in in vitro models of neuronal stress and Aβ1–42-mediated toxicity

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