5,710 research outputs found
Imaging Photon Lattice States by Scanning Defect Microscopy
Microwave photons inside lattices of coupled resonators and superconducting
qubits can exhibit surprising matter-like behavior. Realizing such open-system
quantum simulators presents an experimental challenge and requires new tools
and measurement techniques. Here, we introduce Scanning Defect Microscopy as
one such tool and illustrate its use in mapping the normal-mode structure of
microwave photons inside a 49-site Kagome lattice of coplanar waveguide
resonators. Scanning is accomplished by moving a probe equipped with a sapphire
tip across the lattice. This locally perturbs resonator frequencies and induces
shifts of the lattice resonance frequencies which we determine by measuring the
transmission spectrum. From the magnitude of mode shifts we can reconstruct
photon field amplitudes at each lattice site and thus create spatial images of
the photon-lattice normal modes
Universal quantum computation by discontinuous quantum walk
Quantum walks are the quantum-mechanical analog of random walks, in which a
quantum `walker' evolves between initial and final states by traversing the
edges of a graph, either in discrete steps from node to node or via continuous
evolution under the Hamiltonian furnished by the adjacency matrix of the graph.
We present a hybrid scheme for universal quantum computation in which a quantum
walker takes discrete steps of continuous evolution. This `discontinuous'
quantum walk employs perfect quantum state transfer between two nodes of
specific subgraphs chosen to implement a universal gate set, thereby ensuring
unitary evolution without requiring the introduction of an ancillary coin
space. The run time is linear in the number of simulated qubits and gates. The
scheme allows multiple runs of the algorithm to be executed almost
simultaneously by starting walkers one timestep apart.Comment: 7 pages, revte
Suicidal behavior in individuals accused or convicted of child sex abuse or indecent image offenses: systematic review of prevalence and risk factors
Objective
An emerging body of research indicates that child sex abuse (CSA) offenders are at high risk of suicide when their offenses come to light and that those accused of accessing indecent images of children (IIOC) are at particular risk.
Methods
We conducted a systematic review and narrative synthesis on suicide rates and risk factors in this population of offenders. A keyword search of bibliographic databases (PsycINFO, Ovid, MEDLINE, Embase, PILOTS, SCIE, the Cochrane Central Register of Controlled Trials [CENTRAL] and CINAHL) was conducted.
Results
Eighteen articles were included in the review, with eleven studies meeting criteria for quality assessment. The risk of suicide in perpetrators of CSA and IIOC might be over 100 times that of the general population, although estimates vary widely between studies. Several complex, interlinking factors were identified as associated with risk, including shame, unique demographic characteristics of the offenders, absence of prior criminal contact, and the impact of a criminal investigation.
Conclusions
The review identified factors that may have practical, clinical, and operational implications in the prevention of suicide in CSA and IIOC perpetrators. Exploring the impact of the investigation itself on suicide risk, including potential operational strategies and clinical input to reduce risk, should be a priority
Enhanced nasopharyngeal infection and shedding associated with an epidemic lineage of emm3 group A Streptococcus
Background:
A group A Streptococcus (GAS) lineage of genotype emm3, sequence type 15 (ST15) was
associated with a six month upsurge in invasive GAS disease in the UK. The epidemic lineage
(Lineage C) had lost two typical emm3 prophages, Φ315.1 and Φ315.2 associated with the
superantigen ssa, but gained a different prophage (ΦUK-M3.1) associated with a different
superantigen, speC and a DNAse spd1.
Methods and Results:
The presence of speC and spd1 in Lineage C ST15 strains enhanced both in vitro mitogenic
and DNAse activities over non-Lineage C ST15 strains. Invasive disease models in Galleria
mellonella and SPEC-sensitive transgenic mice, revealed no difference in overall invasiveness
of Lineage C ST15 strains compared to non-Lineage C ST15 strains, consistent with clinical
and epidemiological analysis. Lineage C strains did however markedly prolong murine nasal
infection with enhanced nasal and airborne shedding compared to non-Lineage C strains.
Deletion of speC or spd1 in two Lineage C strains identified a possible role for spd1 in airborne
shedding from the murine nasopharynx.
Conclusions:
Nasopharyngeal infection and shedding of Lineage C strains was enhanced compared to nonLineage
C strains and this was, in part, mediated by the gain of the DNase spd1 through prophage acquisition
Screening and diagnostic assessment of neurodevelopmental disorders in a male prison
Purpose
The purpose of this paper is to identify neurodevelopmental disorders and difficulties (NDD) in a male prison. The study used standardised tools to carry out screening and diagnostic assessment of the attention deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD) and intellectual disability (ID).
Design/methodology/approach
The ADHD self-report scale, 20-item autism quotient and the Learning Disability Screening Questionnaire were used to screen 240 male prisoners. Prisoners who screened positive on one or more of these scales or self-reported a diagnosis of ADHD, ASD or ID were further assessed using the diagnostic interview for ADHD in adults, adapted Autism Diagnostic Observation Schedule and the Quick Test.
Findings
Of the 87 prisoners who screened positive for NDD and were further assessed, 70 met the study’s diagnostic criteria for ADHD, ASD or ID. Most of those with NDD (51 per cent) had previously gone unrecognised and a high proportion (51 per cent) were identified through staff- or self-referral to the study.
Originality/value
The study demonstrated that improving awareness and providing access to skilled, standardised assessment within a male prison can result in increased recognition and identification of NDD
Single-qubit unitary gates by graph scattering
We consider the effects of plane-wave states scattering off finite graphs, as
an approach to implementing single-qubit unitary operations within the
continuous-time quantum walk framework of universal quantum computation. Four
semi-infinite tails are attached at arbitrary points of a given graph,
representing the input and output registers of a single qubit. For a range of
momentum eigenstates, we enumerate all of the graphs with up to vertices
for which the scattering implements a single-qubit gate. As increases, the
number of new unitary operations increases exponentially, and for the
majority correspond to rotations about axes distributed roughly uniformly
across the Bloch sphere. Rotations by both rational and irrational multiples of
are found.Comment: 8 pages, 7 figure
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