Model building and beyond.

An introduction to the Proceedings of the 2020 CCP4 Study Weekend on model building which are available as a virtual issue at https://journals.iucr.org/special_issues/2020/CCP42020/.

Controlling the Formation of Conductive Pathways in Memristive Devices.

Resistive random-access memories are promising candidates for novel computer architectures such as in-memory computing, multilevel data storage, and neuromorphics. Their working principle is based on electrically stimulated materials changes that allow access to two (digital), multiple (multilevel), or quasi-continuous (analog) resistive states. However, the stochastic nature of forming and switching the conductive pathway involves complex atomistic defect configurations resulting in considerable variability.

Soil macroaggregation drives sequestration of organic carbon and nitrogen with three-year grass-clover leys in arable rotations.

Conventional arable cropping with annual crops established by ploughing and harrowing degrades larger soil aggregates that contribute to storing soil organic carbon (SOC). The urgent need to increase SOC content of arable soils to improve their functioning and sequester atmospheric CO has motivated studies into the effects of reintroducing leys into long-term conventional arable fields. However, effects of short-term leys on total SOC accumulation have been equivocal.

Percutaneous Revascularization for Ischemic Left Ventricular Dysfunction.

Background: Whether revascularization by percutaneous coronary intervention (PCI) can improve event-free survival and left ventricular function in patients with severe ischemic left ventricular systolic dysfunction, as compared with optimal medical therapy (i.e., individually adjusted pharmacologic and device therapy for heart failure) alone, is unknown.

Structural insight on the mechanism of an electron-bifurcating [FeFe] hydrogenase.

Electron bifurcation is a fundamental energy conservation mechanism in nature in which two electrons from an intermediate-potential electron donor are split so that one is sent along a high-potential pathway to a high-potential acceptor and the other is sent along a low-potential pathway to a low-potential acceptor. This process allows endergonic reactions to be driven by exergonic ones and is an alternative, less recognized, mechanism of energy coupling to the well-known chemiosmotic principle. The electron-bifurcating [FeFe] hydrogenase from (HydABC) requires both NADH and ferredoxin to reduce protons generating hydrogen.

In Vision It Is Groups, Rather Than Maps, That Determine How We Perceive the World.

This paper presents the results of a study that used a speeded counting task to adjudicate between two competing theories of how perceptual representations of visual objects are derived. Boolean map (BM) theory assumes that there are strict limits on conscious awareness, such that we only have serial access to features on the same dimension (e.g.

Measuring quality of dying, death and end-of-life care for children and young people: A scoping review of available tools.

Background: The circumstances and care provided at the end of a child's life have a profound impact on family members. Although assessing experiences and outcomes during this time is challenging, healthcare professionals have a responsibility to ensure high quality of care is provided.

Aim: To identify available tools which measure the quality of dying, death and end-of-life care for children and young people; describe the content, and data on validity and reliability of existing tools.

Dynamic and Flexible Survival Models for Extrapolation of Relative Survival: A Case Study and Simulation Study.

Background: Extrapolation of survival data is a key task in health technology assessments (HTAs), which may be improved by incorporating general population mortality data via relative survival models. Dynamic survival models are a promising method for extrapolation that may be expanded to dynamic relative survival models (DRSMs), a novel development presented here. There are currently neither examples of dynamic models in HTA nor comparisons of DRSMs with other relative survival models when used for survival extrapolation.

"If I don't smoke shisha, I won't be able to sleep": lived experiences of high school students in Ethiopia.

Background: Shisha smoking predisposes the users to cardiovascular diseases, cancer, and infections, such as tuberculosis, hepatitis, and herpes. In Ethiopia, there is little data on the adolescents' shisha smoking experience. This study aimed to explore the lived experience of high school students and inform ongoing and future prevention and control interventions.

Evaluation of activity of fosfomycin, and synergy in combination, in Gram-negative bloodstream infection isolates in a UK teaching hospital.

Fosfomycin has retained activity against many multi-drug resistant (MDR) Gram-negatives, and may be useful against extended spectrum beta-lactamase (ESBL) producing and carbapenem-resistant Enterobacterales to improve clinical outcomes. There are few data from the UK on the susceptibility of invasive Gram-negative isolates to fosfomycin, especially in the era of increasing use of oral fosfomycin for urinary tract infections (UTIs). We evaluated fosfomycin susceptibility against 100 consecutive Gram-negative bloodstream isolates, both individually, and in combination with other mechanistically similar and differing antibiotics.

Activity-based protein profiling reveals dynamic substrate-specific cellulase secretion by saprotrophic basidiomycetes.

Background: Fungal saccharification of lignocellulosic biomass occurs concurrently with the secretion of a diverse collection of proteins, together functioning as a catalytic system to liberate soluble sugars from insoluble composite biomaterials. How different fungi respond to different substrates is of fundamental interest to the developing biomass saccharification industry. Among the cornerstones of fungal enzyme systems are the highly expressed cellulases (endo-β-glucanases and cellobiohydrolases).

Monitoring Different Social Media Platforms to Report Unplanned School Closures Due to Wildfires in California, October and December 2017.

Objective: Researchers at the Centers for Disease Control and Prevention monitor unplanned school closure (USC) reports through online systematic searches (OSS) to assist public health emergency responses. We counted the additional reports identified through social media along with OSS to improve USC monitoring.

Methods: Facebook and Twitter data of public-school districts and private schools in counties affected by California wildfires in October and December of 2017 and January of 2018 were retrieved.

Multikink quantile regression for longitudinal data with application to progesterone data analysis.

Motivated by investigating the relationship between progesterone and the days in a menstrual cycle in a longitudinal study, we propose a multikink quantile regression model for longitudinal data analysis. It relaxes the linearity condition and assumes different regression forms in different regions of the domain of the threshold covariate. In this paper, we first propose a multikink quantile regression for longitudinal data.

Detecting and identifying glycoside hydrolases using cyclophellitol-derived activity-based probes.

The ability to detect active enzymes in a complex mixture of folded proteins (e.g., secretome, cell lysate) generally relies on observations of catalytic ability, necessitating the development of an activity assay that is compatible with the sample and selective for the enzyme(s) of interest.

Widespread association of ERα with RMRP and tRNA genes in MCF-7 cells and breast cancers.

tRNA gene transcription by RNA polymerase III (Pol III) is a tightly regulated process, but dysregulated Pol III transcription is widely observed in cancers. Approximately 75% of all breast cancers are positive for expression of Estrogen Receptor alpha (ERα), which acts as a key driver of disease. MCF-7 cells rapidly upregulate tRNA gene transcription in response to estrogen and ChIP-PCR demonstrated ERα enrichment at tRNA and 5S rRNA genes in this breast cancer cell line.

Synthesis of broad-specificity activity-based probes for -β-mannosidases.

-β-mannosidases are a broad class of stereochemically retaining hydrolases that are essential for the breakdown of complex carbohydrate substrates found in all kingdoms of life. Yet the detection of -β-mannosidases in complex biological samples remains challenging, necessitating the development of new methodologies. Cyclophellitol and its analogues selectively label the catalytic nucleophiles of retaining glycoside hydrolases, making them valuable tool compounds.

Correction: Glycosylated cyclophellitol-derived activity-based probes and inhibitors for cellulases.

[This corrects the article DOI: 10.1039/D0CB00045K.].

Cost Effectiveness of Digital Interventions for Generalised Anxiety Disorder: A Model-Based Analysis.

Background: Digital interventions (DIs) are increasingly being used in mental health care, despite limited evidence regarding their value for money. This study aimed to evaluate the cost effectiveness of DIs for generalised anxiety disorder (GAD), in comparison with alternative care options, from the perspective of the UK health care system.

Methods: An open-source decision analytic cohort model was used to extrapolate the results of a network meta-analysis over a patient's lifetime and estimate the costs and outcomes (quality-adjusted life-years) of DIs and their comparators.

Aggregating Twitter Text through Generalized Linear Regression Models for Tweet Popularity Prediction and Automatic Topic Classification.

Social media platforms have become accessible resources for health data analysis. However, the advanced computational techniques involved in big data text mining and analysis are challenging for public health data analysts to apply. This study proposes and explores the feasibility of a novel yet straightforward method by regressing the outcome of interest on the aggregated influence scores for association and/or classification analyses based on generalized linear models.

Improving oral health in people with severe mental illness (SMI): A systematic review.

Background: Those with severe mental illness (SMI) are at greater risk of having poor oral health, which can have an impact on daily activities such as eating, socialising and working. There is currently a lack of evidence to suggest which oral health interventions are effective for improving oral health outcomes for people with SMI.

Aims: This systematic review aims to examine the effectiveness of oral health interventions in improving oral health outcomes for those with SMI.

Comparing current and emerging practice models for the extrapolation of survival data: a simulation study and case-study.

Background: Estimates of future survival can be a key evidence source when deciding if a medical treatment should be funded. Current practice is to use standard parametric models for generating extrapolations. Several emerging, more flexible, survival models are available which can provide improved within-sample fit.