5,133 research outputs found
New Zealand Guidelines for cyanobacteria in recreational fresh waters: Interim Guidelines
This document is divided into four main sections, plus 14 appendices.
Section 1. Introduction provides an overview of the purpose and status of the document as well as advice on who should use it.
Section 2. Framework provides a background to the overall guidelines approach, recommendations on agency roles and responsibilities, and information on the condition of use of this document.
Section 3. Guidelines describes the recommended three-tier monitoring and action sequence for planktonic and benthic cyanobacteria.
Section 4. Sampling provides advice on sampling planktonic and benthic cyanobacteria.
The appendices give further background information and include templates for data collection and reporting, including:
• background information on known cyanotoxins and their distribution in New Zealand
• information on the derivation of guideline values
• photographs of typical bloom events
• a list of biovolumes for common New Zealand cyanobacteria
• templates for field assessments
• suggested media releases and warning sign templates.
A glossary provides definitions for abbreviations and terms used in these guidelines
How does the kinase Lck phosphorylate the T cell receptor? Spatial organization as a regulatory mechanism
T cell signaling begins with the ligation of the T cell antigen receptor (TCR) by a cognate peptide and the phosphorylation of the receptor’s immunoreceptor tyrosine-based activation motif domains by the kinase Lck. However, the canonical receptor model is insufficient to explain how the constitutively active kinase Lck can discriminate between non-ligated and ligated TCRs. Here, we discuss the factors that are thought to regulate the spatial distribution of the TCR and Lck, and therefore critically influence TCR signaling initiation
Cardiovascular disease biomarkers are associated with declining renal function in type 2 diabetes
Aims/hypothesis:
We investigated whether biochemical cardiovascular risk factors and/or markers of subclinical cardiovascular disease were associated with the development of reduced renal function in people with type 2 diabetes.
Methods:
A cohort of 1066 Scottish men and women aged 60–74 years with type 2 diabetes from the Edinburgh Type 2 Diabetes Study were followed up for a median of 6.7 years. New-onset reduced renal function was defined as two eGFRs <60 ml−1 min−1 (1.73 m)−2 at least 3 months apart with a > 25% decline from baseline eGFR. Ankle brachial pressure index (ABI), N-terminal pro-B-type natriuretic peptide (NT-proBNP) and high-sensitivity troponin T (hsTnT) were measured at baseline. Pulse wave velocity (PWV) and carotid intima media thickness were measured 1 year into follow-up. Data were analysed using Cox proportional hazards models.
Results:
A total of 119 participants developed reduced renal function during follow-up. ABI, PWV, NT-proBNP and hsTnT were all associated with onset of decline in renal function following adjustment for age and sex. These associations were attenuated after adjustment for additional diabetes renal disease risk factors (systolic BP, baseline eGFR, albumin:creatinine ratio and smoking pack-years), with the exception of hsTnT which remained independently associated (HR 1.51 [95% CI 1.22, 1.87]). Inclusion of hsTnT in a predictive model improved the continuous net reclassification index by 0.165 (0.008, 0.286).
Conclusions/interpretation:
Our findings demonstrate an association between hsTnT, a marker of subclinical cardiac ischaemia, and subsequent renal function decline. Further research is required to establish the predictive value of hsTnT and response to intervention
Subsystem symmetry enriched topological order in three dimensions
We introduce a model of three-dimensional (3D) topological order enriched by
planar subsystem symmetries. The model is constructed starting from the 3D
toric code, whose ground state can be viewed as an equal-weight superposition
of two-dimensional (2D) membrane coverings. We then decorate those membranes
with 2D cluster states possessing symmetry-protected topological order under
line-like subsystem symmetries. This endows the decorated model with planar
subsystem symmetries under which the loop-like excitations of the toric code
fractionalize, resulting in an extensive degeneracy per unit length of the
excitation. We also show that the value of the topological entanglement entropy
is larger than that of the toric code for certain bipartitions due to the
subsystem symmetry enrichment. Our model can be obtained by gauging the global
symmetry of a short-range entangled model which has symmetry-protected
topological order coming from an interplay of global and subsystem symmetries.
We study the non-trivial action of the symmetries on boundary of this model,
uncovering a mixed boundary anomaly between global and subsystem symmetries. To
further study this interplay, we consider gauging several different subgroups
of the total symmetry. The resulting network of models, which includes models
with fracton topological order, showcases more of the possible types of
subsystem symmetry enrichment that can occur in 3D.Comment: 21 pages. v2: Published version. Updated Section IV with new figure
and tabl
Topological defect networks for fractons of all types
Fracton phases exhibit striking behavior which appears to render them beyond the standard topological quantum field theory (TQFT) paradigm for classifying gapped quantum matter. Here, we explore fracton phases from the perspective of defect TQFTs and show that topological defect networks—networks of topological defects embedded in stratified 3+1-dimensional (3+1D) TQFTs—provide a unified framework for describing various types of gapped fracton phases. In this picture, the subdimensional excitations characteristic of fractonic matter are a consequence of mobility restrictions imposed by the defect network. We conjecture that all gapped phases, including fracton phases, admit a topological defect network description and support this claim by explicitly providing such a construction for many well-known fracton models, including the X-cube and Haah's B code. To highlight the generality of our framework, we also provide a defect network construction of a fracton phase hosting non-Abelian fractons. As a byproduct of this construction, we obtain a generalized membrane-net description for fractonic ground states as well as an argument that our conjecture implies no topological fracton phases exist in 2+1-dimensional gapped systems. Our paper also sheds light on techniques for constructing higher-order gapped boundaries of 3+1D TQFTs
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