bluuebunny/crossref_metadata_2025 huggingface dataset:
Optical gas sensor based on the combination of a QD photoluminescent probe and a QD photodetector
Authors: Mitri Federica , De Iacovo Andrea , De Santis Serena , Quarta Danila , Giansante Carlo , Orsini Monica , Colace Lorenzo
Published: August 2022

We report on a sensor architecture for detection of hazardous gases. The proposed device is based on the integration of a solid-state quantum dot (QD) photoluminescent probe with a QD photodetector on the same substrate. The effectiveness of the approach is demonstrated by developing a compact optical sensor for trace detection of explosives in air. The proposed architecture is very simple and consists of a silicon substrate with both surfaces coated with QD films. The upper layer acts as photoluminescent probe, pumped by a blue LED. The change of photoluminescence intensity associated to the interaction between the QDs and the target analyte is measured by the QD photodetector fabricated on the opposite side of the substrate. The sensor is mounted into a small chamber provided with the LED and the front-end electronics. The device is characterized by using nitrobenzene as representative nitroaromatic compound. Extremely low concentrations (down to 0.1 ppm) can be detected by the proposed device, with a theoretical detection limit estimated to be as low as 2 ppb. Results are repeatable and no ageing effect is observed over a 70 d period. The proposed architecture may provide a promising solution for explosive detection in air as well as other sensing applications, thanks to its sensitivity, simple fabrication process, practical usability and cost effectiveness.
A simple classroom exercise for teaching principles of ultrasound diagnostic using two springs
Authors: Pašić Selim , Popara Nato
Published: August 2022

We present a novel method for demonstrating the physical principles of ultrasound imaging at a level suitable for educational programmes up to the university level, using a simple mechanical model that is very inexpensive and accessible to a broad variety of educational institutions. The method revolves around the use of one or two steel springs that can be extended on a flat surface. The spring represents a tissue and the longitudinal wave traveling along the spring represents the propagation of an ultrasound wave in tissue. This method allows students to gain direct experience with wave propagation, reflection and transmission in tissue as well as insight into the physical processes underlying ultrasound imaging. These include equally the ultrasound diagnostic device measurement of the depth of various tissue boundaries, modelled as a simple measurement of the time elapsed between the emission of a wave and the detection of a wave reflected from an object intersecting the spring. An ultrasound device probes the boundary between a formation (an organ or a lesion) and surrounding tissue by registering the amplitude of reflection on the formation, which is proportional to a difference in acoustic impedance between the formation and the tissue. The amplitude of the reflected wave in our apparatus is also proportional to acoustic impedance between the spring and an object like a plastic ruler intersecting the spring, whose stiffness and consequently acoustic impedance can be adjusted by its offset. It is also easy to clearly see the reflected wave on the boundary of two coupled springs (two tissues) with different acoustic impedances. We represent a series of representative measurements using our mechanical model demonstrating its good precision.
Mechanistic modelling of oxygen enhancement ratio of radiation via Monte Carlo simulation-based DNA damage calculation
Authors: Lai Youfang , Chi Yujie , Jia Xun
Published: August 2022

Objective. Oxygen plays an important role in affecting the cellular radio-sensitivity to ionizing radiation. The objective of this study is to build a mechanistic model to compute oxygen enhancement ratio (OER) using a GPU-based Monte Carlo (MC) simulation package gMicroMC for microscopic radiation transport simulation and DNA damage calculation. Approach. We first simulated the water radiolysis process in the presence of DNA and oxygen for 1 ns and recorded the produced DNA damages. In this process, chemical reactions among oxygen, water radiolysis free radicals and DNA molecules were considered. We then applied a probabilistic approach to model the reactions between oxygen and indirect DNA damages for a maximal reaction time of t
0. Finally, we defined two parameters P
0 and P
1, representing probabilities for DNA damages without and with oxygen fixation effect not being restored in the repair process, to compute the final DNA double strand breaks (DSBs). As cell survival fraction is mainly determined by the number of DSBs, we assumed that the same numbers of DSBs resulted in the same cell survival rates, which enabled us to compute the OER as the ratio of doses producing the same number of DSBs without and with oxygen. We determined the three parameters (t
0, P
0 and P
1) by fitting the OERs obtained in our computation to a set of published experimental data under x-ray irradiation. We then validated the model by performing OER studies under proton irradiation and studied model sensitivity to parameter values. Main results. We obtained the model parameters as t
0 = 3.8 ms, P
0 = 0.08, and P
1 = 0.28 with a mean difference of 3.8% between the OERs computed by our model and that obtained from experimental measurements under x-ray irradiation. Applying the established model to proton irradiation, we obtained OERs as functions of oxygen concentration, LET, and dose values, which generally agreed with published experimental data. The parameter sensitivity analysis revealed that the absolute magnitude of the OER curve relied on the values of P
0 and P
1, while the curve was subject to a horizontal shift when adjusting t
0. Significance. This study developed a mechanistic model that fully relies on microscopic MC simulations to compute OER.
Snap-through behavior of bistable beam with variable sections: mechanical model and experimental study
Authors: Zhang Zhongwen , Chen Li-Wei , Xu Zhao-Dong
Published: August 2022

Bistable and multistable structures with snap-through behavior can achieve nonlinear and negative stiffness based on their geometric nonlinearity in elastic deformation. Traditionally, loading capacity and stiffness of this kind of structure tend to be relatively low, a drawback that can potentially be overcome by making section bistable beams varying along its length. However, there currently lacks a systematic evaluation on influences of the sectional alignment on its mechanical performance. Based on the chained constrained beam model, a simplified method for calculating the structure is derived in this paper. The method is validated by a series of tests. Using the method, a systematic parametric study is performed and optimization studies are conducted to establish the best achievable mechanical behavior of the bistable structure subjected to different design limitations. Influences of the stiffness of the lateral restraints on performance of the structure are also investigated. At last, a structure based on the bistable beams connected in parallel were designed using the proposed methodology and tested.
Analytical solutions of (2+1)-dimensional Calogero-Bogoyavlenskii-Schiff equation in fluid mechanics/plasma physics using the New Kudryashov method
Authors: Cinar Melih , Secer Aydin , Bayram Mustafa
Published: August 2022

This study investigates various analytic soliton solutions of the generalized (2+1)-dimensional Calogero-Bogoyavlenskii-Schiff (CBS) equation in fluid dynamics and plasma physics using a recently introduced technique which is the New Kudryashov method. Moreover, it is examined how the wave propagation in both directions represented by the CBS equation occurs. The considered equation describes the interaction of the long propagating wave in the x axis with the Riemann propagating wave along the y axis. To get traveling wave solutions of the CBS equation, it is transformed into a nonlinear ordinary differential equation (NLODE) using a proper wave transformation. Supposing that the NLODE has some solutions in the form provided by the method, one can obtain a nonlinear system of algebraic equations. The unknowns in the system can be found by solving the system via computer algebraic systems such as Mathematica and Maple, etc. Substituting the unknowns into the trial solutions provided by the method, we get the solutions of the NLODE. Then, putting wave transformations back into the solutions of NLODE, we get the solutions of the considered CBS equation. We present the 2D, 3D and contour plots to illustrate the physical behavior of the obtained solutions using the appropriate parameters. Besides, the schematic representation of wave motion of the soliton along both spatial axes and its interpretation are given. The used novel technique can be used for a wide range of partial differential equations (PDEs) in the real world. It is expected that the derived soliton solutions might be helpful for better understanding the wave behavior and so, it might contribute to future studies in various disciplines.
Magnon control of light transmission in a  -symmetric-like cavity magnomechanical system
Authors: Ding Ming-Song , Shi Ying , Liu Yu-Jie , Zheng Li
Published: August 2022

We theoretically study magnon control of light transmission in a cavity magnomechanical system, which consists of an active magnon mode and a passive microwave cavity mode. Phonon-magnon coupling and cavity photon-magnon coupling can be achieved via magnetostrictive interaction and magnetic dipole interaction respectively in this system. By driving a small ferromagnetic sphere which connected by an optical fiber to the inner wall of a microwave cavity, the effective magnon-gain can be obtained. We find that the transparent, absorptive and amplificatory windows can appear by adjusting the gain of the magnon mode, and the introduction of gain can realize significant amplification of transmitted probe power, especially at the EP point. In comparison with traditional optomechanically induced amplification, the amplification can be controlled not only by adjusting the driving field and magnon-microwave coupling, but also by adjusting the external magnetic field. Our results lays a theoretical foundation for the study of the magnon control in magnomechanical systems.
Negative differential thermal conductance between Weyl semimetals nanoparticles through vacuum
Authors: Sun Yasong , Hu Yang , Shi Kezhang , Zhang Jihong , Feng Dudong , Wu Xiaohu
Published: August 2022

In this work, the near-field radiative heat transfer (NFRHT) between two Weyl semimetal (WSM) nanoparticles (NPs) is investigated. The numerical results show that negative differential thermal conductance (NDTC) effect can be obtained in this system, i.e., when the temperature of the emitter is fixed, the heat flux does not decrease monotonically with the increase of the temperature of the receiver. Specifically, when the temperature of the emitter is 300 K, the heat flux is identical when the temperature of the receiver is 50 K or 280 K. The NDTC effect is attributed to the fact that the permittivity of the WSMs changes with the temperature. The coupling effects of polarizability of two WSM NPs have been further identified at different temperature to reveal the physical mechanism of the NDTC effect. In addition, the NFRHT between two WSM NPs can be greatly enhanced by exciting the localized plasmon and circular modes. This work indicates that the WSMs maybe promising candidate materials for manipulating NFRHT.
BAO scale inference from biased tracers using the EFT likelihood
Authors: Babić Ivana , Schmidt Fabian , Tucci Beatriz
Published: August 2022

The physical scale corresponding to baryon acoustic oscillations (BAO), the size of the
sound horizon at recombination, is precisely determined by CMB experiments. Measuring the
apparent size of the BAO scale imprinted in the clustering of galaxies gives us a direct estimate
of the angular-diameter distance and the Hubble parameter as a function of redshift. The BAO
feature is damped by non-linear structure formation, which reduces the precision with which we can
infer the BAO scale from standard galaxy clustering analysis methods. Many methods to undo this
damping via the so-called BAO reconstruction have so far been proposed; however, they all rely on
backward modeling. In this paper, we present the first results of isotropic BAO inference from
rest-frame halo catalogs using forward modeling combined with the EFT likelihood, in the case
where the initial phases of the density field are fixed. We show that the remaining systematic
bias is less than 2% when we consider cutoff values of Λ ≤ 0.25 h Mpc-1 
for all halo samples considered, and below 1% and consistent with zero for all but the most
highly biased samples. We also demonstrate that, when compared to the standard power spectrum
likelihood approach under the same assumption of fixed phases, the 1σ errors associated to
the field level inference of the BAO scale are 1.1 to 3.3 times smaller, depending on the value of
the cutoff and the halo sample. Our analysis therefore unveils another promising feature of using
field-level inference for high-precision cosmology.
High energy particles from young supernovae: gamma-ray and neutrino connections
Authors: Sarmah Prantik , Chakraborty Sovan , Tamborra Irene , Auchettl Katie
Published: August 2022

Young core-collapse supernovae (YSNe)
are factories of high-energy neutrinos and gamma-rays as the shock accelerated protons efficiently interact with the protons in the
dense circumstellar medium. We explore the detection prospects of secondary particles from YSNe of Type
IIn, II-P, IIb/II-L, and Ib/c.
Type IIn YSNe are found to produce the largest flux of neutrinos and gamma-rays, followed by II-P YSNe.
Fermi-LAT and the Cherenkov Telescope Array (IceCube-Gen2) have the potential to detect Type IIn YSNe up to 10 Mpc (4 Mpc),
with the remaining YSNe Types being detectable closer to Earth.
We also find that YSNe may dominate the diffuse neutrino background, especially between 10 TeV and 103 TeV, while they do not constitute a dominant component to the isotropic gamma-ray background observed by Fermi-LAT. At the same time, the IceCube high-energy starting events and Fermi-LAT data already allow us to exclude a large fraction of the model parameter space of YSNe otherwise inferred from multi-wavelength electromagnetic observations of these transients.
Perturbative construction of mean-field equations in extensive-rank matrix factorization and denoising
Authors: Maillard Antoine , Krzakala Florent , Mézard Marc , Zdeborová Lenka
Published: August 2022

Factorization of matrices where the rank of the two factors diverges linearly with their sizes has many applications in diverse areas such as unsupervised representation learning, dictionary learning or sparse coding. We consider a setting where the two factors are generated from known component-wise independent prior distributions, and the statistician observes a (possibly noisy) component-wise function of their matrix product. In the limit where the dimensions of the matrices tend to infinity, but their ratios remain fixed, we expect to be able to derive closed form expressions for the optimal mean squared error on the estimation of the two factors. However, this remains a very involved mathematical and algorithmic problem. A related, but simpler, problem is extensive-rank matrix denoising, where one aims to reconstruct a matrix with extensive but usually small rank from noisy measurements. In this paper, we approach both these problems using high-temperature expansions at fixed order parameters. This allows to clarify how previous attempts at solving these problems failed at finding an asymptotically exact solution. We provide a systematic way to derive the corrections to these existing approximations, taking into account the structure of correlations particular to the problem. Finally, we illustrate our approach in detail on the case of extensive-rank matrix denoising. We compare our results with known optimal rotationally-invariant estimators, and show how exact asymptotic calculations of the minimal error can be performed using extensive-rank matrix integrals.
Socially-differentiated urban metabolism methodology informs equity in coupled carbon-air pollution mitigation strategies: insights from three Indian cities
Authors: Nagpure Ajay Singh , Tong Kangkang , Ramaswami Anu
Published: August 2022

A differentiated urban metabolism methodology is developed to quantify inequality and inform social equity in urban infrastructure strategies aimed at mitigating local in-boundary PM2.5 and co-beneficially reducing transboundary greenhouse gas (GHG) emissions. The method differentiates community-wide local PM2.5 and transboundary GHG emission contributions by households of different income strata, alongside commercial and industrial activities. Applied in three Indian cities (Delhi, Coimbatore, and Rajkot) through development of new data sets, method yields key insights that across all three cities, top-20% highest-income households dominated motorized transportation, electricity, and construction activities, while poorest-20% homes dominated biomass and kerosene use, resulting in the top-20% households contributing more than three times GHGs as the bottom-20% homes. Further, after including commercial and industrial users, top-20% households contributed as much or more in-boundary PM2.5 emissions than
all
commercial OR
all
industrial emitters (e.g. Delhi’s top-20% homes contributed 21% of in-boundary PM2.5 similar to industries at 21%. These results enabled co-benefit analysis of various infrastructure transition strategies on the horizon, finding only three could yield both significant GHG and PM2.5 reductions (>2%-each): (a) Modest 10% efficiency improvements among top-20% households, industry and commercial sectors, requiring a focus on wealthiest homes; (b) Phasing out all biomass and kerosene use within cities (impacting poorest); (c) Replacing gas and diesel vehicles with renewable electric vehicles. The differentiated PM2.5 and GHG emissions data-informed social equity in the design of the three co-beneficial infrastructure transitions by: (a)-prioritizing free/subsidized clean cooking fuels to poorest homes; (b)-increasing electricity block rates and behavioral nudging for wealthiest homes; and, (c)-prioritizing electrification of mass transit and promoting electric two-wheelers ahead of providing subsidies for electric cars, where the free-rider phenomenon can occur, which benefits wealthiest homes. The methodology is broadly translatable to cities worldwide, while the policy insights are relevant to rapidly urbanizing Asia and Africa to advance clean, low-carbon urban infrastructure transitions.
First passage in discrete-time absorbing Markov chains under stochastic resetting
Authors: Chen Hanshuang , Li Guofeng , Huang Feng
Published: August 2022

First passage of stochastic processes under resetting has recently been an active research topic in the field of statistical physics. However, most of previous studies mainly focused on the systems with continuous time and space. In this paper, we study the effect of stochastic resetting on first passage properties of discrete-time absorbing Markov chains, described by a transition matrix Q between transient states and a transition matrix R from transient states to absorbing states. Using a renewal approach, we exactly derive the unconditional mean first passage time (MFPT) to any absorbing state, the splitting probabilities and the conditional MFPT to a specific absorbing state without hitting any other absorbing state. All the quantities can be expressed in terms of a deformed fundamental matrix

Z

γ

=

I
−

(

1
−
γ

)

Q

−
1

and R, where I is the identity matrix, and γ is the resetting probability at each time step. We further show a sufficient condition under which the unconditional MPFT can be optimized by stochastic resetting. Finally, we apply our results to two concrete examples: symmetric random walks on one-dimensional lattices with absorbing boundaries and voter model on complete graphs.
The SAGEX review on scattering amplitudes Chapter 3: Mathematical structures in Feynman integrals
Authors: Abreu Samuel , Britto Ruth , Duhr Claude
Published: August 2022

Dimensionally-regulated Feynman integrals are a cornerstone of all perturbative computations in quantum field theory. They are known to exhibit a rich mathematical structure, which has led to the development of powerful new techniques for their computation. We review some of the most recent advances in our understanding of the analytic structure of multiloop Feynman integrals in dimensional regularisation. In particular, we give an overview of modern approaches to computing Feynman integrals using differential equations, and we discuss some of the properties of the functions that appear in the solutions. We then review how dimensional regularisation has a natural mathematical interpretation in terms of the theory of twisted cohomology groups, and how many of the well-known ideas about Feynman integrals arise naturally in this context.
Stochastic resetting of a population of random walks with resetting-rate-dependent diffusivity
Authors: Bertin Eric
Published: August 2022

We consider the problem of diffusion with stochastic resetting in a population of random walks where the diffusion coefficient is not constant, but behaves as a power-law of the average resetting rate of the population. Resetting occurs only beyond a threshold distance from the origin. This problem is motivated by physical realizations like soft matter under shear, where diffusion of a walk is induced by resetting events of other walks. We first reformulate in the broader context of diffusion with stochastic resetting the so-called Hébraud–Lequeux model for plasticity in dense soft matter, in which diffusivity is proportional to the average resetting rate. Depending on parameter values, the response to a weak external field may be either linear, or non-linear with a non-zero average position for a vanishing applied field, and the transition between these two regimes may be interpreted as a continuous phase transition. Extending the model by considering a general power-law relation between diffusivity and average resetting rate, we notably find a discontinuous phase transition between a finite diffusivity and a vanishing diffusivity in the small field limit.
Genetic relationship of microstructure and mechanical properties between ferrite/pearlite steel plate and billet
Authors: Feng Rui , Li Zongheng , Li Hui , Zhao Weichao , Gan Kefu , Wang Yucheng , Zhao Guiju , Ma Jin
Published: August 2022

This paper proposed the double-pass compression thermal/force simulation experiment to in situ analyze the phase transformation of continuous casting billet during the controlled rolling and controlled cooling process. The genetic relationship between the central segregation of the billet and solute element distribution of the steel plate, and also the genetic relationship of microstructure and mechanical properties between them were experimentally studied. The results show that the microstructure and mechanical properties between the billet and corresponding batch of steel plate have the genetic relationship, and the link of the relationship is central segregation. The phase transformation of supercooling austenite will be affected by the central segregation of Mn and C elements, and the granular bainite abnormal segregation band is the transformation product of Mn and C element segregation region.
PD-L1 Expression in Colorectal Adenocarcinoma Is Associated With the Tumor Immune Microenvironment and Epithelial-Mesenchymal Transition
Authors: Secinti Ilke Evrim , Ozgur Tumay , Dede Isa
Published: August 2022

Objectives

Colorectal carcinomas are the third-most common tumors in the world, and colorectal cancer ranks second in cancer-related deaths. Our aim in this study was to investigate the correlation between programmed cell death ligand 1 (PD-L1) expression and clinicopathologic parameters in colorectal carcinomas and their relationship to the tumor immune microenvironment, epithelial-mesenchymal transition (EMT), and microsatellite instability. We also investigated the predictive and prognostic role of PD-L1.

Methods

One hundred patients with a diagnosis of colorectal adenocarcinoma who did not receive neoadjuvant therapy were included in the study. The relationships among the altered expression of PD-L1; vimentin; E-cadherin; mismatch repair status; and pathologic microenvironmental features, including the presence of tumor budding and CD8-positive tumor infiltrating lymphocytes (TILs), were assessed.

Results

Increased PD-L1 expression in tumor cells was associated with increased TILs (P = .013), high histologic grade (P = .011), advanced pathologic T stage (P = .007), lymph node metastasis (P = .002), distant metastasis (P < .001), perineural invasion (P = .009), high bud score (P = .023), EMT (P < .001), and shorter disease-free survival (P = .029).

Conclusions

Overall, PD-L1 expression in colorectal carcinoma tumor cells is a marker of poor prognosis, and the positive correlation detected between EMT status and PD-L1 expression suggests that patients with the mesenchymal phenotype may be more likely to benefit from programmed cell death 1 protein/PD-L1 immunotherapy.
iEnhancer-DLRA: identification of enhancers and their strengths by a self-attention fusion strategy for local and global features
Authors: Zeng Li , Liu Yang , Yu Zu-Guo , Liu Yuansheng
Published: August 2022

Identification and classification of enhancers are highly significant because they play crucial roles in controlling gene transcription. Recently, several deep learning-based methods for identifying enhancers and their strengths have been developed. However, existing methods are usually limited because they use only local or only global features. The combination of local and global features is critical to further improve the prediction performance. In this work, we propose a novel deep learning-based method, called iEnhancer-DLRA, to identify enhancers and their strengths. iEnhancer-DLRA extracts local and multi-scale global features of sequences by using a residual convolutional network and two bidirectional long short-term memory networks. Then, a self-attention fusion strategy is proposed to deeply integrate these local and global features. The experimental results on the independent test dataset indicate that iEnhancer-DLRA performs better than nine existing state-of-the-art methods in both identification and classification of enhancers in almost all metrics. iEnhancer-DLRA achieves 13.8% (for identifying enhancers) and 12.6% (for classifying strengths) improvement in accuracy compared with the best existing state-of-the-art method. This is the first time that the accuracy of an enhancer identifier exceeds 0.9 and the accuracy of the enhancer classifier exceeds 0.8 on the independent test set. Moreover, iEnhancer-DLRA achieves superior predictive performance on the rice dataset compared with the state-of-the-art method RiceENN.
Complex genome assembly based on long-read sequencing
Authors: Zhang Tianjiao , Zhou Jie , Gao Wentao , Jia Yuran , Wei Yanan , Wang Guohua
Published: August 2022

High-quality genome chromosome-scale sequences provide an important basis for genomics downstream analysis, especially the construction of haplotype-resolved and complete genomes, which plays a key role in genome annotation, mutation detection, evolutionary analysis, gene function research, comparative genomics and other aspects. However, genome-wide short-read sequencing is difficult to produce a complete genome in the face of a complex genome with high duplication and multiple heterozygosity. The emergence of long-read sequencing technology has greatly improved the integrity of complex genome assembly. We review a variety of computational methods for complex genome assembly and describe in detail the theories, innovations and shortcomings of collapsed, semi-collapsed and uncollapsed assemblers based on long reads. Among the three methods, uncollapsed assembly is the most correct and complete way to represent genomes. In addition, genome assembly is closely related to haplotype reconstruction, that is uncollapsed assembly realizes haplotype reconstruction, and haplotype reconstruction promotes uncollapsed assembly. We hope that gapless, telomere-to-telomere and accurate assembly of complex genomes can be truly routinely achieved using only a simple process or a single tool in the future.
Bootstrapping Whittle estimators
Authors: Kreiss J -P , Paparoditis E
Published: August 2022

Fitting parametric models by optimizing frequency-domain objective functions is an attractive approach of parameter estimation in time series analysis. Whittle estimators are a prominent example in this context. Under weak conditions and the assumption that the true spectral density of the underlying process does not necessarily belong to the parametric class of spectral densities fitted, the distribution of Whittle estimators typically depends on difficult to estimate characteristics of the underlying process. This makes the implementation of asymptotic results for the construction of confidence intervals or for assessing the variability of estimators difficult in practice. In this paper we propose a frequency-domain bootstrap method to estimate the distribution of Whittle estimators that is asymptotically valid under assumptions that not only allow for possible model misspecification, but also for weak dependence conditions that are satisfied by a wide range of stationary stochastic processes. Adaptations of the bootstrap procedure developed to incorporate different modifications of Whittle estimators proposed in the literature, such as, for instance, tapered, debiased or boundary extended Whittle estimators, are also considered. Simulations demonstrate the capabilities of the bootstrap method proposed and its good finite sample performance. A real-life data analysis on sunspots is also presented.
Risk Factors for Developing Inflammatory Bowel Disease Within and Across Families with a Family History of IBD
Authors: Torres Joana , Gomes Catarina , Jensen Camilla B , Agrawal Manasi , Ribeiro-Mourão Francisco , Jess Tine , Colombel Jean-Frédéric , Allin Kristine H , Burisch Johan
Published: August 2022

Introduction

A family history of inflammatory bowel disease [IBD] is the strongest risk factor for disease. However, some first-degree relatives (FDRs) will develop disease, while others will not.

Methods

Using the nationwide Danish National Patient Register, we examined risk factors in families with two or more affected FDRs. First, we compared exposures between siblings with and without IBD within the same family [within-family analysis]. Second, we compared exposures between individuals with and without IBD across all families [across-family analysis]. Exposures included sex, birth order, mode of delivery, antibiotics, personal and family history of immune-mediated diseases, gastrointestinal infections, and surgical history preceding diagnosis. Uni- and multivariable conditional logistic regression analyses were conducted.

Results

In the ‘within-family analysis’, 1669 families were included [1732 cases, 2447 controls]. Female sex (adjusted odds ratio [aOR]: 1.40, 95% confidence interval [CI] 1.23, 1.59), history of ankylosing spondylitis [aOR: 2.88, 95% CI 1.05, 7.91] and exposure to antibiotics [aOR: 1.28, 95% CI 1.02, 1.61] increased the risk for IBD. In the ‘across-family analysis’, 1254 cases and 37 584 controls were included, confirming an association with prior ankylosing spondylitis [aOR: 3.92, 95% CI 1.38, 11.12] and exposure to antibiotics [aOR: 1.29, 95% CI 1.04, 1.60]. Having two or more relatives [aOR: 6.26, 95% CI 1.34, 29.29] or a sibling with IBD [aOR: 1.36, 95% CI 1.18, 1.57] increased the risk of IBD. Appendectomy reduced the risk of ulcerative colitis [aOR: 0.32, 95% CI 0.14, 0.72].

Conclusion

In families with IBD, we identified risk factors for the unaffected FDR to develop disease. These findings provide an opportunity for counselling IBD relatives.
Technology-delivered motivational interviewing to improve health outcomes in patients with chronic conditions: a systematic review of the literature
Authors: Baricchi Marina , Vellone Ercole , Caruso Rosario , Arrigoni Cristina , Dellafiore Federica , Ghizzardi Greta , Pedroni Cristina , Pucciarelli Gianluca , Alvaro Rosaria , Iovino Paolo
Published: August 2022

Aims

Provide an overview of remote motivational interviewing (MI) interventions for chronically ill patients, and understand their degree of effectiveness on different health outcomes.

Methods and results

A systematic review with meta-analysis was conducted using the following databases: PubMed, CINAHL, PsychInfo, and Web of Science. Eligibility criteria included studies that administered remote MI alone or in combination with other remote approaches. A narrative synthesis and two meta-analyses were performed. Fifteen studies met the inclusion criteria. MI administration almost exclusively occurred by telephone and individual sessions. Eight studies reported treatment fidelity aspects, and four declared adopting a theoretical framework. Most targeted outcomes were therapeutic adherence, physical activity, depression, quality of life, and mortality. Risk of bias varied markedly, with the largest source resulting from selection process and intervention performance. The two meta-analyses indicated a significant effect of MI on depression [standardized mean difference = –0.20, 95% confidence interval (CI): –0.34, –0.05, Z = 2.73, P = 0.006, I2 = 0%], and no effect of MI on glycosylated haemoglobin (mean difference = –0.02, 95% CI: –0.48, 0.45, P = 0.94, I2 = 84%).

Conclusion

Remote MI can be a promising approach for improving depression in chronic disease patients. However, studies are inconclusive due to risks of bias, heterogeneity, and lack of reporting of interventionist’s training, treatment fidelity, and theoretical frameworks’ use. More studies with solid designs are needed to inform clinical decision-making and research.

Registration

PROSPERO: CRD42021241516.
Transcription factors perform a 2-step search of the nucleus
Authors: Staller Max Valentín
Published: August 2022

Transcription factors regulate gene expression by binding to regulatory DNA and recruiting regulatory protein complexes. The DNA-binding and protein-binding functions of transcription factors are traditionally described as independent functions performed by modular protein domains. Here, I argue that genome binding can be a 2-part process with both DNA-binding and protein-binding steps, enabling transcription factors to perform a 2-step search of the nucleus to find their appropriate binding sites in a eukaryotic genome. I support this hypothesis with new and old results in the literature, discuss how this hypothesis parsimoniously resolves outstanding problems, and present testable predictions.
Renal and Urological Disorders Associated With Inflammatory Bowel Disease
Authors: Kumar Shankar , Pollok Richard , Goldsmith David
Published: August 2022

Renal and urinary tract complications related to inflammatory bowel disease (IBD) have been relatively understudied in the literature compared with other extraintestinal manifestations. Presentation of these renal manifestations can be subtle, and their detection is complicated by a lack of clarity regarding the optimal screening and routine monitoring of renal function in IBD patients. Urolithiasis is the most common manifestation. Penetrating Crohn’s disease involving the genitourinary system as an extraintestinal complication is rare but associated with considerable morbidity. Some biologic agents used to treat IBD have been implicated in progressive renal impairment, although differentiating between drug-related side effects and deteriorating kidney function due to extraintestinal manifestations can be challenging. The most common findings on renal biopsy of IBD patients with renal injury are tubulointerstitial nephritis and IgA nephropathy, the former also being associated with drug-induced nephrotoxicity related to IBD medication. Amyloidosis, albeit rare, must be diagnosed early to reduce the chance of progression to renal failure. In this review, we evaluate the key literature relating to renal and urological involvement in IBD and emphasize the high index of suspicion required for the prompt diagnosis and treatment of these manifestations and complications, considering the potential severity and implications of acute or chronic loss of renal function. We also provide suggestions for future research priorities.
The interplay between volunteers and firm’s employees in distributed innovation: emergent architectures and stigmergy in open source software
Authors: Dalle Jean-Michel , David Paul A , Rullani Francesco , Bolici Francesco
Published: August 2022

This paper focuses on the interplay between firms and open and collaborative innovation communities. We develop a formal model where both volunteers (agents setting their agendas freely) and firm’s employees (agents whose agenda is mostly set by their employer) participate in the creation of a common artifact. In this framework, we discuss how firms can influence the architecture of the emerging product to assure fast and performant development and a desirable distribution of innovative labor within the project team. We find that closing the project only to employees implies high speed and performance if employees are given autonomy in certain dimensions and are directed in others. In this case, however, we observe a trade-off in terms of ideal core–periphery division of labor on one side and development speed and performance on the other side. At the opposite extreme, creating a volunteer-only project can ease the trade-off but assures positive results only if the firm is able to set up an entry mechanism that “surgically” selects volunteers with specific preferences. A mixture of both employees and volunteers can strike a good balance, relaxing the two constraints.
Judges as equilibrists: Explaining judicial activism in Latin America
Authors: Pereira Gabriel
Published: August 2022

Intense forms of judicial activism have emerged in Latin America in the last three decades. Judges dictated structural remedies decisions (SRDs) to create, design, and implement public policies to redress structural human rights violations, implementing permanent judicial monitoring of the policy process. In a region marked by judicial instability, SRDs are risky options for judges. They can be seen as strong challenges to the government and, thus, prompt retaliation. They can also damage judges’ reputations as they might be strongly criticized by influential conservative groups of society that oppose progressive structural reforms. What drives judges to pursue or avoid this kind of risky activism? I propose the equilibrist approach, an alternative model to standard accounts explaining judicial behavior in Latin America. It incorporates the legitimacy-building dimension of the strategic game and predicts some level of assertiveness but one that is careful about the preferences of elites, the mass public, and opinion leaders. I use the institutional yet fragile Argentine Supreme Court to test the model, as it decided several SDRs in the early 2000s.
Predictors of blood pressure and hypertension long-term after treatment of isolated coarctation of the aorta in children—a population-based study
Authors: Ylinen Mari K , Pihkala Jaana I , Salminen Jukka T , Sarkola Taisto
Published: August 2022

OBJECTIVES

The aim of this study was to assess predictors of BP and hypertension and relations between BP and LV mass in a population-based retrospective study of repaired isolated coarctation of aorta.

METHODS

We collected follow-up data until 2018 of 284/304 (93%) patients with coarctation treated by surgery (n = 235) or balloon angioplasty/stent (n = 37/12) in our unit 2000–2012. Systolic hypertension was defined as systolic BP (SBP) z-score ≥+2 standard deviation (SD) or regular use of BP medication. LV hypertrophy was defined as LV mass z-score ≥+2 SD or LV mass index g/m2.7 ≥95th percentile.

RESULTS

The median (25–75th percentiles) follow-up time and age at follow-up were 9.7 years (6.9–13.2) and 11.8 years (7.9–16.0), respectively. Age at first procedure (P = 0.011) and systolic arm-leg-gradient (P = 0.007) were positively and transverse arch (P = 0.007) and isthmus diameter (P = 0.001) z-scores at follow-up were negatively associated with SBP z-score adjusted for age at follow-up and need for reintervention for coarctation. Systolic hypertension was present in 53/284 (18.7%) and related with increasing age at first procedure (median 33.2 vs 0.6 months; P < 0.001) and arm-leg-gradient at follow-up (mean ± SD, −0.3 ± 14.6 vs −6.4 ± 11.6 mmHg; P = 0.047) adjusted for reintervention for coarctation and age at follow-up. LV hypertrophy was present in 20/227 (9.3%) and related with SBP z-score.

CONCLUSIONS

Higher SBP and hypertension in repaired coarctation of aorta are related with increasing age at first procedure and arm-leg-gradient at follow-up. Transverse arch and isthmus diameters at follow-up are inversely related with SBP.
Eye drop instillation technique among patients with glaucoma and evaluation of pharmacists’ roles in improving their technique: an exploratory study
Authors: Kan Ying Min , Kho Boon Phiaw , Kong Lillian , Chong Qiao Xuan , Tiong Ming Nguong Jonathan , Wong Ling Mei Joyce
Published: August 2022

Objectives

This study aimed to explore the eye drop instillation technique of patients with glaucoma and whether a pharmacist-led counselling session can improve their technique. Patients’ perceptions of pharmacists’ role in providing the counselling were also explored.

Methods

This cross-sectional study was conducted between December 2020 and March 2021 at Sarawak General Hospital, Malaysia. Convenience sampling was used to recruit patients with glaucoma who self-administered their eye drops. Participants’ background information were obtained using an investigator-administered questionnaire before their eye drop instillation technique was assessed. Those with imperfect techniques were counselled by a pharmacist before being reassessed. Differences in eye drop instillation competency were determined using paired T-test.

Key findings

A total of 138 participants were recruited. Participants were on a median of two eye drops (IQR 2-4) for a median of five years (IQR 2-8). Prior to being counselled, they demonstrated a mean total of 8.4/13 steps (SD 2.33) correctly. A statistically significant improvement in eye drop instillation technique was observed post-pharmacists’ counselling, with a mean increase of 4.3 steps demonstrated correctly (95% CI, 4.0 to 4.7, P < 0.001). The majority of participants agreed that pharmacists are knowledgeable in providing counselling on eye drop administration techniques.

Conclusions

Patients with glaucoma treated at Sarawak General Hospital had imperfect eye drop instillation techniques, despite most having used their eye drops for several years. Interventions by pharmacists to improve eye drop instillation are crucial to optimise the medical treatment of patients with glaucoma.
Intestinal Injury in Ugandan Children Hospitalized With Malaria
Authors: Ngai Michelle , Hawkes Michael T , Erice Clara , Weckman Andrea M , Wright Julie , Stefanova Veselina , Opoka Robert O , Namasopo Sophie , Conroy Andrea L , Kain Kevin C
Published: August 2022

Background

Severe malaria is associated with multiple organ dysfunction syndrome (MODS), which may involve the gastrointestinal tract.

Methods

In a prospective cohort study in Uganda, we measured markers of intestinal injury (intestinal fatty-acid binding protein [I-FABP] and zonula occludens-1 [ZO-1]) and microbial translocation (lipopolysaccharide binding protein [LBP] and soluble complement of differentiation 14 [sCD14]) among children admitted with malaria. We examined their association with biomarkers of inflammation, endothelial activation, clinical signs of hypoperfusion, organ injury, and mortality.

Results

We enrolled 523 children (median age 1.5 years, 46% female, 7.5% mortality). Intestinal FABP was above the normal range (≥400 pg/mL) in 415 of 523 patients (79%). Intestinal FABP correlated with ZO-1 (ρ = 0.11, P = .014), sCD14 (ρ = 0.12, P = .0046) as well as markers of inflammation and endothelial activation. Higher I-FABP levels were associated with lower systolic blood pressure (ρ = −0.14, P = .0015), delayed capillary refill time (ρ = 0.17, P = .00011), higher lactate level (ρ = 0.40, P < .0001), increasing stage of acute kidney injury (ρ = 0.20, P = .0034), and coma (P < .0001). Admission I-FABP levels ≥5.6 ng/mL were associated with a 7.4-fold higher relative risk of in-hospital death (95% confidence interval, 1.4–11, P = .0016).

Conclusions

Intestinal injury occurs commonly in children hospitalized with malaria and is associated with microbial translocation, systemic inflammation, tissue hypoperfusion, MODS, and fatal outcome.
Case report: evaluation of an open-source synthetic data platform for simulation studies
Authors: Meeker Daniella , Kallem Crystal , Heras Yan , Garcia Stephanie , Thompson Casey
Published: August 2022

Simulation is a mainstay of comparative- and cost-effectiveness research when empirical data are not available. The Synthea platform, originally designed for generating realistically coded longitudinal health records for software testing, implements data generation models specified in publicly contributed modules representing patients’ life cycle and disease and treatment progression. We test the hypothesis that Synthea can be used for simulation studies that draw parameters from observational studies and randomized trials. We benchmarked the results and assessed the effort required to create a Synthea module that replicates a recently published cost-effectiveness simulation comparing levofloxacin prophylaxis to usual care for leukemia. A module was iteratively developed using published parameters from the original study; we replicated the initial conditions and simulation endpoints of demographics, health events, costs, and mortality. We compare Synthea’s Generic Module Framework to platforms designed for simulation and show that Synthea can be used, with modifications, for some types of simulation studies.
When May UN Peacekeepers Use Lethal Force to Protect Civilians? Reconciling Threats to Civilians, Imminence, and the Right to Life
Authors: Bourgeois Hanna , Labuda Patryk I
Published: August 2022

While the use of force in UN peacekeeping was traditionally limited to self-defence, the UN Security Council now regularly deploys peacekeeping missions with robust mandates to protect civilians and encourages their proactive implementation, including by using force. For many years, the Security Council authorised the use of ‘all necessary means’ to protect civilians from ‘imminent threats’ of physical violence, but its recent mandates have often dropped references to ‘imminence’. The UN has also interpreted such mandates as broader authorisation for peacekeepers to use force in response to temporally ill-defined threats to civilians. This turn to robust civilian protection is often celebrated, yet the legal parameters of using force continue to evolve below the radar and are rarely scrutinised, with scholarly writing focused on peacekeeper self-defence, rules of engagement and UN policy to justify proactive mandate implementation. Drawing on an analysis of the relationship between peacekeeping mandates and international law in light of the shift from defensive to proactive peacekeeping, this article argues that the legality of using force for civilian protection purposes must be reconciled not only with Security Council resolutions and their language on imminence, but also with human rights law (HRL), which imposes strict temporal conditions for lawful deprivations of the right to life outside the conduct of hostilities. Using examples of how the UN’s current practice of using force to protect civilians in hostile environments may contravene international norms, this article attempts to reconcile proactive civilian-oriented peacekeeping with the concept of imminence as understood in HRL.