2,822 research outputs found
The transmission of nosocomial pathogens in an intensive care unit: a space–time clustering and structural equation modelling approach
We investigated the incidence of cases of nosocomial pathogens and risk factors in an intensive treatment unit ward to determine if the number of cases is dependent on location of patients and the colonization/infection history of the ward. A clustering approach method was developed to investigate the patterns of spread of cases through time for five microorganisms [methicillin-resistant Staphylococcus aureus (MRSA), Acinetobacter spp., Klebsiella spp., Candida spp., and Pseudomonas aeruginosa] using hospital microbiological monitoring data and ward records of patient-bed use. Cases of colonization/infection by MRSA, Candida and Pseudomonas were clustered in beds and through time while cases of Klebsiella and Acinetobacter were not. We used structural equation modelling to analyse interacting risk factors and the potential pathways of transmission in the ward. Prior nurse contact with colonized/infected patients, mediated by the number of patient-bed movements, were important predictors for all cases, except for those of Pseudomonas. General health and invasive surgery were significant predictors of cases of Candida and Klebsiella. We suggest that isolation and bed movement as a strategy to manage MRSA infections is likely to impact upon the incidence of cases of other opportunist pathogen
Finite-key security against coherent attacks in quantum key distribution
The work by Christandl, K\"onig and Renner [Phys. Rev. Lett. 102, 020504
(2009)] provides in particular the possibility of studying unconditional
security in the finite-key regime for all discrete-variable protocols. We spell
out this bound from their general formalism. Then we apply it to the study of a
recently proposed protocol [Laing et al., Phys. Rev. A 82, 012304 (2010)]. This
protocol is meaningful when the alignment of Alice's and Bob's reference frames
is not monitored and may vary with time. In this scenario, the notion of
asymptotic key rate has hardly any operational meaning, because if one waits
too long time, the average correlations are smeared out and no security can be
inferred. Therefore, finite-key analysis is necessary to find the maximal
achievable secret key rate and the corresponding optimal number of signals.Comment: 9 pages, 4 figure
Novel loss-of-function mutation in HERC2 is associated with severe developmental delay and paediatric lethality
Background: The HERC2 gene encodes a 527 kDa E3 ubiquitin protein ligase that has key roles in cell cycle regulation, spindle formation during mitosis, mitochondrial functions and DNA damage responses. It has essential roles during embryonic development, particularly for neuronal and muscular functions. To date, missense mutations in HERC2 have been associated with an autosomal recessive neurodevelopmental disorder with some phenotypical similarities to Angelman syndrome, and a homozygous deletion spanning HERC2 and OCA2 causing a more severe neurodevelopmental phenotype.
Methods and results: We ascertained a consanguineous family with a presumed autosomal recessive severe neurodevelopmental disorder that leads to paediatric lethality. In affected individuals, we identified a homozygous HERC2 frameshift variant that results in a premature stop codon and complete loss of HERC2 protein. Functional characterisation of this variant in fibroblasts, from one living affected individual, revealed impaired mitochondrial network and function as well as disrupted levels of known interacting proteins such as XPA.
Conclusion: This study extends the genotype–phenotype correlation for HERC2 variants to include a distinct lethal neurodevelopmental disorder, highlighting the importance of further characterisation for HERC2-related disorders
Family/Partnership-centered Conjoint Behavioral Consultation: The Reconceptualization of a Model
• The importance of working meaningfully and constructively with families in promoting a child’s learning and adjustment is unequivocal. Home-school partnerships have been shown to relate to many positive outcomes for children, families, teachers, and schools. • Conjoint Behavioral Consultation (CBC; Sheridan, Kratochwill, & Bergan, 1996) is a structured, indirect model of service delivery whereby parents and teachers are joined to collaboratively address needs and concerns of a child with the assistance of a consultant. Goals of CBC encompass those focused on addressing child needs, and developing home-school partnerships. • CBC is procedurally operationalized via conjoint interviews (Problem Identification, Problem Analysis, and Treatment Evaluation) aimed at prioritizing shared concerns across home and school settings, evaluating factors contributing to the identified concern, developing an agreeable plan, and evaluating the child’s progress toward goals. • Traditional approaches to CBC emphasize a problem-solving orientation, aimed largely at addressing problems experienced by individual children
Application of surface-modified metal hydrides for hydrogen separation from gas mixtures containing carbon dioxide and monoxide
Application of surface-modified MH material for H2 separation using temperature/pressure swing absorption–desorption was studied. The substrate alloy had the following composition LaNi3.55Co0.75Al0.4-Mn0.3, and the surface modification was carried out through fluorination followed by aminosilane functionalization and electroless deposition of Pd. The material was found to have good poisoning tolerance towards surface adsorbates, even for the large (rv1.5 kg) batches. Feasibility of its application for H2 separation from gas mixtures (up to 30% CO2 and 100 ppm CO) was demonstrated by testing of a prototype H2 separation system (rv280 g of MH in two reactors), and H2 separation reactor (0.75 kg of MH). The H2 separation was characterized by stable performances in the duration of 250 absorption/desorption cycles. However, the total process productivity was found to be limited by the sluggish H2 absorption (partial H2 pressure 62.5 bar, temperature below 100 °C). In the presence of CO2 and CO, additional deceleration of H2 absorption was observed at space velocities of the feed gas below 5000 hWeb of Scienc
The shocklet transform: a decomposition method for the identification of local, mechanism-driven dynamics in sociotechnical time series
We introduce a qualitative, shape-based, timescale-independent time-domain transform used to extract local dynamics from sociotechnical time series—termed the Discrete Shocklet Transform (DST)—and an associated similarity search routine, the Shocklet Transform And Ranking (STAR) algorithm, that indicates time windows during which panels of time series display qualitatively-similar anomalous behavior. After distinguishing our algorithms from other methods used in anomaly detection and time series similarity search, such as the matrix profile, seasonal-hybrid ESD, and discrete wavelet transform-based procedures, we demonstrate the DST’s ability to identify mechanism-driven dynamics at a wide range of timescales and its relative insensitivity to functional parameterization. As an application, we analyze a sociotechnical data source (usage frequencies for a subset of words on Twitter) and highlight our algorithms’ utility by using them to extract both a typology of mechanistic local dynamics and a data-driven narrative of socially-important events as perceived by English-language Twitter
Hurricanes and hashtags: Characterizing online collective attention for natural disasters
We study collective attention paid towards hurricanes through the lens of
-grams on Twitter, a social media platform with global reach. Using
hurricane name mentions as a proxy for awareness, we find that the exogenous
temporal dynamics are remarkably similar across storms, but that overall
collective attention varies widely even among storms causing comparable deaths
and damage. We construct `hurricane attention maps' and observe that hurricanes
causing deaths on (or economic damage to) the continental United States
generate substantially more attention in English language tweets than those
that do not. We find that a hurricane's Saffir-Simpson wind scale category
assignment is strongly associated with the amount of attention it receives.
Higher category storms receive higher proportional increases of attention per
proportional increases in number of deaths or dollars of damage, than lower
category storms. The most damaging and deadly storms of the 2010s, Hurricanes
Harvey and Maria, generated the most attention and were remembered the longest,
respectively. On average, a category 5 storm receives 4.6 times more attention
than a category 1 storm causing the same number of deaths and economic damage.Comment: 31 pages (14 main, 17 Supplemental), 19 figures (5 main, 14 appendix
An experimental study to discriminate between the validity of diffraction theories for off-Bragg replay
We show that experiments clearly verify the assumptions made by the
first-order two-wave coupling theory for one dimensional lossless unslanted
planar volume holographic gratings using the beta-value method rather than
Kogelnik's K-vector closure method. Apart from the fact that the diffraction
process is elastic, a much more striking difference between the theories
becomes apparent particularly in the direction of the diffracted beam in
off-Bragg replay. We therefore monitored the direction of the diffracted beam
as a function of the off-Bragg replay angle in two distinct cases: [a] the
diffracted beam lies in the plane of incidence and [b] the sample surface
normal, the grating vector and the incoming beam do not form a plane which
calls for the vectorial theory and results in conical scattering.Comment: Corrected Eqs. (3) & (6); 14 pages, 8 figure
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