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Self-organization scheme for balanced routing in large-scale multi-hop networks
No full textWe propose a self-organization scheme for cost-effective and load-balanced routing in multi-hop networks. To avoid overloading nodes that provide favourable routing conditions, we assign each node with a cost function that penalizes high loads. Thus, finding routes to sink nodes is formulated as an optimization problem in which the global objective function strikes a balance between route costs and node loads. We apply belief propagation (its min-sum version) to solve the network optimization problem and obtain a distributed algorithm whereby the nodes collectively discover globally optimal routes by performing low-complexity computations and exchanging messages with their neighbours. We prove that the proposed method converges to the global optimum after a finite number of local exchanges of messages. Finally, we demonstrate numerically our framework's efficacy in balancing the node loads and study the trade-off between load reduction and total cost minimization
Deep extragalactic visible legacy survey (DEVILS): stellar mass growth by morphological type since z=1
No full textUsing high-resolution Hubble Space Telescope imaging data, we perform a visual morphological classification of ∼36 000 galaxies at z 1 as the fraction of irregular galaxies and merger systems (when observed at rest-frame UV/blue wavelengths) dramatically increases. We determine that roughly two-thirds of the total stellar mass of the Universe today was in place by z ∼ 1. Double-component galaxies dominate the SMD at all epochs and increase in their contribution to the stellar mass budget to the present day. Elliptical galaxies are the second most dominant morphological type and increase their SMD by ∼2.5 times, while by contrast, the pure-disc population significantly decreases by ∼85 per cent. According to the evolution of both high- and low-mass ends of the SMF, we find that mergers and in situ evolution in discs are both present at z < 1, and conclude that double-component galaxies are predominantly being built by the in situ evolution in discs (apparent as the growth of the low-mass end with time), while mergers are likely responsible for the growth of ellipticals (apparent as the increase of intermediate/high-mass end)
Emergence of dengue virus serotype 2 in Mauritania and molecular characterization of its circulation in West Africa
No full textThe number of sporadic and epidemic dengue fever cases have reportedly been increasing in recent years in some West African countries, such as Senegal and Mali. The first epidemic of laboratory-confirmed dengue occurred in Nouakchott, the capital city of Mauritania situated in the Saharan desert, in 2014. On-site diagnosis of dengue fever was established using a rapid diagnostic test for dengue. In parallel, the presence of Aedes aegypti mosquitoes in the city was confirmed. The initial diagnosis was confirmed by RT-PCR, which showed that all samples from the 2014 dengue epidemic in Nouakchott were dengue virus serotype 2 (DENV-2). The whole genome or envelope protein gene of these strains, together with other DENV-2 strains obtained from travelers returning from West African countries to France between 2016 and 2019 (including two Mauritanian strains in 2017 and 2018), were sequenced. Phylogenetic analysis suggested a recent emergence of an epidemic strain from the cosmopolitan genotype belonging to West African cosmopolitan lineage II, which is genetically distinct from African sylvatic genotype. The origin of this DENV-2 lineage is still unknown, but our data seem to suggest a recent and rapid dispersion of the epidemic strain throughout the region. More complete genome sequences of West African DENV-2 are required for a better understanding of the dynamics of its circulation. Arboviral surveillance and outbreak forecasting are urgently needed in West Africa
Impact of the COVID-19 pandemic on community antibiotic prescribing and stewardship: A qualitative interview study with general practitioners in England
No full textThe COVID-19 pandemic has had a profound impact on the delivery of primary care services. We aimed to identify general practitioners’ (GPs’) perceptions and experiences of how the COVID-19 pandemic influenced antibiotic prescribing and antimicrobial stewardship (AMS) in general practice in England. Twenty-four semi-structured interviews were conducted with 18 GPs at two time-points: autumn 2020 (14 interviews) and spring 2021 (10 interviews). Interviews were audio-recorded, transcribed and analysed thematically, taking a longitudinal approach. Participants reported a lower threshold for antibiotic prescribing (and fewer consultations) for respiratory infections and COVID-19 symptoms early in the pandemic, then returning to more usual (pre-pandemic) prescribing. They perceived the pandemic as having had less impact on antibiotic prescribing for urinary and skin infections. Participants perceived the changing ways of working and consulting (e.g., proportions of remote and in-person consultations) in addition to changing patient presentations and GP workloads as influencing the fluctuations in antibiotic prescribing. This was compounded by decreased engagement with, and priority of, AMS due to COVID-19-related urgent priorities. Re-engagement with AMS is needed, e.g., through reviving antibiotic prescribing feedback and targets/incentives. The pandemic disrupted, and required adaptations in, the usual ways of working and AMS. It is now important to identify opportunities, e.g., for re-organising ways of managing infections and AMS in the future
Neuronal non-CG methylation is an essential target for MeCP2 function
No full textDNA methylation is implicated in neuronal biology via the protein MeCP2, the mutation of which causes Rett syndrome. MeCP2 recruits the NCOR1/2 co-repressor complexes to methylated cytosine in the CG dinucleotide, but also to sites of non-CG methylation, which are abundant in neurons. To test the biological significance of the dual-binding specificity of MeCP2, we replaced its DNA binding domain with an orthologous domain from MBD2, which can only bind mCG motifs. Knockin mice expressing the domain-swap protein displayed severe Rett-syndrome-like phenotypes, indicating that normal brain function requires the interaction of MeCP2 with sites of non-CG methylation, specifically mCAC. The results support the notion that the delayed onset of Rett syndrome is due to the simultaneous post-natal accumulation of mCAC and its reader MeCP2. Intriguingly, genes dysregulated in both Mecp2 null and domain-swap mice are implicated in other neurological disorders, potentially highlighting targets of relevance to the Rett syndrome phenotype
QUILT: quantify, infer and label the thermal efficiency of heating and cooling residential homes
No full textThe European Parliament have set a target of at least a 32.5% improvement in energy efficiency by 2030. In the EU residential sector, heating and cooling account for half of the energy usage alone, hence there is a need to make homes more thermally efficient. However, there are currently a lack of tools to evaluate the thermal efficiency of homes at scale as previous methods have been intrusive, costly, or inaccurate. More recent approaches have shown that the thermal efficiency of homes can be inferred with non-intrusive methods using only smart-meter and weather data. However, to deploy such algorithms at scale, steps must be taken to quantify in which scenarios it works, and to account for the uncertainty of the inferred thermal efficiency. To address this, we propose QUILT, a non-intrusive, data-driven framework to quantify the thermal efficiency of a home, grounded in physical models of heat flow, which works with heating and cooling systems. A Bayesian model is used to account for the uncertainty associated with data sources and parameters in the thermal model. QUILT is evaluated on real data to demonstrate its feasibility in real world scenarios, and also on simulated data used by the U.S. Department of Energy to evaluate the performance in scenarios not currently captured in real-world datasets. Our experiments quantify the improvements compared to the current state-of-the-art approach by reducing the mean absolute percentage error from 21.6% to 15.6% when inferring the heating power loss coefficient (HPLC), which defines how efficiently a building maintains a heated state given the external temperature. Furthermore, the term cooling power loss coefficient (CPLC) is introduced which is the equivalent to HPLC when the building is in a cooled state, and the feasibility of inferring this metric with QUILT is shown. The analysis also highlights the importance of identifying when the heating is on, and how the HPLC or CPLC can be inferred within a week if the occupants are on holiday given the right weather conditions
Gospel as recipe book: nonlinear reading and practical texts in late antiquity
No full textIn this article, I investigate how Christians and others in late antiquity encountered “the gospel” as a material text. I begin with late ancient practical texts, including ritual formularies, medical handbooks, agricultural guides, and astronomical tables. Users employed portions of these texts in a range of situations, whether by reading aloud or by following the instructions of the text to perform a ritual, prepare a medicine, or cast a horoscope. In order to facilitate use, practical texts were constructed to invite nonlinear access. In this article, I argue that late ancient gospel codices reflect similar strategies of organization and modes of use. Through varied systems of segmentation and reference, the affordances of nonlinear access were integrated into gospel manuscripts. The materiality and textuality of late ancient gospel codices intersect with that of practical texts, providing scripts for performance and inviting nonlinear access. Attending to these varied technologies of access – and to the diverse performative contexts that they underwrite – reveals patterns of knowledge and practice that illuminate “the gospel” as a material text in late antiquity
All‐at‐once solution of linear wave equations
No full textEfficient parallel‐in‐time methods for hyperbolic partial differential equation problems remain scarce. Here we investigate an approach based on circulant preconditioned generalised minimal residual (GMRES) for the monolithic block Toeplitz equations which arise from constant time‐step discretizations. We present theoretical results which guarantee convergence in a number of iterations independent of the number of time‐steps and demonstrate the potential utility of the approach with numerical results employing several different finite difference schemes of varying orders of accuracy
Obesity during childhood is associated with higher cancer mortality rate during adulthood: the i3C Consortium
No full textBackground
In high-income countries, cancer is the leading cause of death among middle-aged adults. Prospective data on the effects of childhood risk exposures on subsequent cancer mortality are scarce.
Methods
We examined whether childhood body mass index (BMI), blood pressure, glucose and lipid levels were associated with adult cancer mortality, using data from 21,012 children enrolled aged 3–19 years in seven prospective cohort studies from the U.S., Australia, and Finland that have followed participants from childhood into adulthood. Cancer mortality (cancer as a primary or secondary cause of death) was captured using registries.
Results
354 cancer deaths occurred over the follow-up. In age-, sex, and cohort-adjusted analyses, childhood BMI (Hazard ratio [HR], 1.13; 95% confidence interval [CI] 1.03–1.24 per 1-SD increase) and childhood glucose (HR 1.22; 95%CI 1.01–1.47 per 1-SD increase), were associated with subsequent cancer mortality. In a multivariable analysis adjusted for age, sex, cohort, and childhood measures of fasting glucose, total cholesterol, triglycerides, and systolic blood pressure, childhood BMI remained as an independent predictor of subsequent cancer mortality (HR, 1.24; 95%CI, 1.03–1.49). The association of childhood BMI and subsequent cancer mortality persisted after adjustment for adulthood BMI (HR for childhood BMI, 1.35; 95%CI 1.12–1.63).
Conclusions
Higher childhood BMI was independently associated with increased overall cancer mortality
Suicidal behavior in individuals accused or convicted of child sex abuse or indecent image offenses: Systematic review of prevalence and risk factors
No full textObjective
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