bluuebunny/crossref_metadata_2025 huggingface dataset:
Lung clearance index predicts pulmonary exacerbations in individuals with primary ciliary dyskinesia: a multicentre cohort study
Authors: Singer Florian , Schlegtendal Anne , Nyilas Sylvia , Vermeulen François , Boon Mieke , Koerner-Rettberg Cordula
Published: January 2021

Background

Lung clearance index (LCI) is a promising lung function outcome in individuals with primary ciliary dyskinesia (PCD). The impact of events clinically important for individuals with PCD, such as pulmonary exacerbations, on LCI is unknown.

Methods

We conducted an international, multicentre, observational cohort study to assess the association of LCI and risk of pulmonary exacerbation, specific changes in LCI during pulmonary exacerbation and global variability of LCI across four visits every 4 months. Ninety individuals with PCD, aged 3–41 years, underwent nitrogen multiple-breath washout (MBW) and spirometry measurements. The association of LCI and pulmonary exacerbations was assessed by Cox proportional hazards and random-effects regression models.

Results

We obtained 430 MBW and 427 spirometry measurements. In total, 379 person-years at risk contributed to the analysis. Per one unit increase (deterioration) in LCI, the risk of future pulmonary exacerbation increased by 13%: HR (95% CI), 1.13 (1.04 to 1.23). If LCI changed from a range of values considered normal to abnormal, the risk of future pulmonary exacerbations increased by 87%: 1.87 (1.08 to 3.23). During pulmonary exacerbations, LCI increased by 1.22 units (14.5%). After pulmonary exacerbations, LCI tended to decline. Estimates of variability in LCI suggested lower variation within individuals compared with variation between individuals. Findings were comparable for forced expiratory volume in 1 s.

Conclusion

On a visit-to-visit basis, LCI measurement may add to the prediction of pulmonary exacerbations, the assessment of lung function decline and the potential lung function response to treatment of pulmonary exacerbations.
‘If not TB, what could it be?’ Chest X-ray findings from the 2016 Kenya Tuberculosis Prevalence Survey
Authors: Mungai Brenda Nyambura , Joekes Elizabeth , Masini Enos , Obasi Angela , Manduku Veronica , Mugi Beatrice , Ong’angò Jane , Kirathe Dickson , Kiplimo Richard , Sitienei Joseph , Oronje Rose , Morton Ben , Squire Stephen Bertel , MacPherson Peter
Published: January 2021

Background

The prevalence of diseases other than TB detected during chest X-ray (CXR) screening is unknown in sub-Saharan Africa. This represents a missed opportunity for identification and treatment of potentially significant disease. Our aim was to describe and quantify non-TB abnormalities identified by TB-focused CXR screening during the 2016 Kenya National TB Prevalence Survey.

Methods

We reviewed a random sample of 1140 adult (≥15 years) CXRs classified as ‘abnormal, suggestive of TB’ or ‘abnormal other’ during field interpretation from the TB prevalence survey. Each image was read (blinded to field classification and study radiologist read) by two expert radiologists, with images classified into one of four major anatomical categories and primary radiological findings. A third reader resolved discrepancies. Prevalence and 95% CIs of abnormalities diagnosis were estimated.

Findings

Cardiomegaly was the most common non-TB abnormality at 259 out of 1123 (23.1%, 95% CI 20.6% to 25.6%), while cardiomegaly with features of cardiac failure occurred in 17 out of 1123 (1.5%, 95% CI 0.9% to 2.4%). We also identified chronic pulmonary pathology including suspected COPD in 3.2% (95% CI 2.3% to 4.4%) and non-specific patterns in 4.6% (95% CI 3.5% to 6.0%). Prevalence of active-TB and severe post-TB lung changes was 3.6% (95% CI 2.6% to 4.8%) and 1.4% (95% CI 0.8% to 2.3%), respectively.

Interpretation

Based on radiological findings, we identified a wide variety of non-TB abnormalities during population-based TB screening. TB prevalence surveys and active case finding activities using mass CXR offer an opportunity to integrate disease screening efforts.

Funding

National Institute for Health Research (IMPALA-grant reference 16/136/35).
Do health halos and conspicuous consumption influence the appeal and risk perceptions of e-cigarettes among young Cambodian men?
Authors: Stubbs Thomas , Thomas Samantha , Pitt Hannah , Daube Mike
Published: January 2021

Introduction

Reduced risk perceptions influence young people’s consumption behaviours of e-cigarettes, suggesting that a health halo effect may be associated with these devices. Product, performative, and social factors contribute to the appeal of e-cigarettes, with young people using e-cigarettes with friends as part of social interactions. This study explored the factors that influence the appeal and risk perceptions associated with e-cigarettes among young Cambodian men.

Methods

A mixed-method, interviewer-administered survey with 147 young men in Cambodia, who were aged between 18 and 24 years and identified as cigarette smokers. Participants described their attitudes and consumption behaviours surrounding e-cigarettes, recalled e-cigarette promotions, and described their risk perceptions towards e-cigarettes. Descriptive statistics were calculated for quantitative data, and thematic analysis was conducted for qualitative data.

Results

Some participants associated e-cigarettes with affluence and exclusivity, describing these devices as products that rich and/or younger people use. Participants also described product attributes that were appealing about e-cigarettes, such as variety of flavours, vapour, and performing smoke ‘styles’ with friends, which differentiated the product from combustible cigarettes. Participants also had reduced risk perceptions towards e-cigarettes, with some commenting that e-cigarettes were not harmful or might be health-enhancing.

Conclusion

Some young people may perceive e-cigarettes as a form of conspicuous consumption, which they associated with social status and identity. A health halo effect appears to be associated with e-cigarettes among some young people. This may influence young people to underestimate the potential health risks associated with these devices.
An online radon monitor for low-background detector assembly facilities
Authors: Pelczar K. , Zuzel G. , Wójcik M. , Pocar A. , Ianni An.
Published: January 2021

Backgrounds from long-lived radon decay products are often problematic for low-energy neutrino and rare-event experiments. These isotopes, specifically $${}^{210}\hbox {Pb}$$

210

Pb

, $${}^{210}\hbox {Bi}$$

210

Bi

, and $${}^{210}\hbox {Po}$$

210

Po

, easily plate out onto surfaces exposed to radon-loaded air. The alpha emitter $${}^{210}\hbox {Po}$$

210

Po

is particularly dangerous for detectors searching for weakly-interacting dark matter particles. Neutrons produced via ($$\upalpha $$
α
, n) reactions in detector materials are, in some cases, a residual background that can limit the sensitivity of the experiment. An effective solution is to reduce the $${}^{222}\hbox {Rn}$$

222

Rn

activity in the air in contact with detector components during fabrication, assembly, commissioning, and operation. We present the design, construction, calibration procedures and performance of an electrostatic radon detector made to monitor two radon-suppressed clean rooms built for the DARKSIDE-50 experiment. A dedicated data acquisition system immune to harsh operating conditions of the radon monitor is also described. A record detection limit for $${}^{222}\hbox {Rn}$$

222

Rn

specific activity in air achieved by the device is $$0.05\,\hbox {mBqm}^{-3}$$

0.05

mBqm

-
3

(STP). The radon concentration of different air samples collected from the two DARKSIDE-50 clean rooms measured with the electrostatic detector is presented.
Fermionic degeneracy and non-local contributions in flag-dipole spinors and mass dimension one fermions
Authors: Lee Cheng-Yang
Published: January 2021

We construct a mass dimension one fermionic field associated with flag-dipole spinors. These spinors are related to Elko (flag-pole spinors) by a one-parameter matrix transformation $${\mathcal {Z}}(z)$$

Z
(
z
)

where z is a complex number. The theory is non-local and non-covariant. While it is possible to obtain a Lorentz-invariant theory via $$\tau $$
τ
-deformation, we choose to study the effects of non-locality and non-covariance. Our motivation for doing so is explained. We show that a fermionic field with $$|z|\ne 1$$

|
z
|
≠
1

and $$|z|=1$$

|
z
|
=
1

are physically equivalent. But for fermionic fields with more than one value of z, their interactions are z-dependent thus introducing an additional fermionic degeneracy that is absent in the Lorentz-invariant theory. We study the fermionic self-interaction and the local U(1) interaction. In the process, we obtained non-local contributions for fermionic self-interaction that have previously been neglected. For the local U(1) theory, the interactions contain time derivatives that renders the interacting density non-commutative at space-like separation. We show that this problem can be resolved by working in the temporal gauge. This issue is also discussed in the context of gravity.
Critical exponents of the O(N)-symmetric $$\phi ^4$$ model from the $$\varepsilon ^7$$ hypergeometric-Meijer resummation
Authors: Shalaby Abouzeid M.
Published: January 2021

We extract the $$\varepsilon $$
ε
-expansion from the recently obtained seven-loop g-expansion for the renormalization group functions of the O(N)-symmetric model. The different series obtained for the critical exponents $$\nu ,\ \omega $$

ν
,

ω

and $$\eta $$
η
have been resummed using our recently introduced hypergeometric-Meijer resummation algorithm. In three dimensions, very precise results have been obtained for all the critical exponents for $$N=0,1,2,3$$

N
=
0
,
1
,
2
,
3

and 4. To shed light on the obvious improvement of the predictions at this order, we obtained the divergence of the specific heat critical exponent $$\alpha $$
α
for the XY model. We found the result $$-0.0123(11)$$

-
0.0123
(
11
)

which is compatible with the famous experimental result of $$-0.0127(3)$$

-
0.0127
(
3
)

from the specific heat of zero gravity liquid helium superfluid transition while the six-loop Borel with conformal mapping resummation result in literature gives the value $$-0.007(3)$$

-
0.007
(
3
)

. For the challenging case of resummation of the $$\varepsilon $$
ε
-expansion series in two dimensions, we showed that our resummation results reflect a significant improvement to the previous six-loop resummation predictions.
Non-axisymmetric Homann stagnation point flow of Maxwell nanofluid towards fixed surface
Authors: Jagwal M. R. , Ahmad I. , Sajid M.
Published: January 2021

In this paper, the heat-transfer enhancement phenomena have been explored for non-axisymmetric Homann stagnation-point flow of Maxwell fluid. Furthermore, Buongiorno’s model for nanofluid is utilized to study remarkable impacts of random (Brownian) motion and thermophoresis of dispersed nanoparticle. The Maxwell nanofluid generates new class of asymmetric stagnation-point flows that depends on ratio [Formula: see text] ([Formula: see text] is shear and [Formula: see text] is strain rate) and Deborah number [Formula: see text]. The numerical and asymptotic consequences of leading equations for current model are obtained using shooting technique. The solution is obtained for diverse values of involved parameters over [Formula: see text]. The wall shear stress, heat/mass transfer rate, velocities, temperature distributions and nanoparticle concentration compared to their large-[Formula: see text] asymptotic behaviors were presented for different values of involved parameters. It is observed that the numerical outcomes of wall shear stress, heat-transfer rate and mass flux best agree with their perturbative solution for large-[Formula: see text]. Moreover, the wall shears [Formula: see text], [Formula: see text] grow as viscoelasticity raises. The reduction in heat flux and particles mass diffusion occurs near the wall boundary-layer due to clustering of nanoparticles. However, heated surface during thermophoresis is pushed nanoparticles into Brownian motion which constitute to enhance the heating process.
Optimal Algorithms for Inverse Eccentric Vertex Location Problem on Extended Star Networks
Authors: Hasanzadeh Mehran , Alizadeh Behrooz , Afrashteh Esmaeil , Baroughi Fahimeh
Published: January 2021

This paper deals with the inverse eccentric vertex location problem on extended star networks in which the aim is to modify the edge lengths at the minimum overall cost within certain modification bounds so that a predetermined vertex becomes the farthest vertex from a given fixed vertex under the new edge lengths. Novel combinatorial algorithms with near-linear time complexities are developed for obtaining the optimal solution of the problem under different cost norms.
Theoretical and experimental status of rare charm decays
Authors: Gisbert Hector , Golz Marcel , Mitzel Dominik Stefan
Published: January 2021

Rare charm decays offer the unique possibility to explore flavor-changing neutral-currents in the up-sector within the Standard Model and beyond. Due to the lack of effective methods to reliably describe its low energy dynamics, rare charm decays have been considered as less promising for long. However, this lack does not exclude the possibility to perform promising searches for New Physics per se, but a different philosophy of work is required. Exact or approximate symmetries of the Standard Model allow to construct clean null-test observables, yielding an excellent road to the discovery of New Physics, complementing the existing studies in the down-sector. In this review, we summarize the theoretical and experimental status of rare charm [Formula: see text] transitions, as well as opportunities for current and future experiments such as LHCb, Belle II, BES III, the FCC-ee and proposed tau-charm factories. We also use the most recent experimental results to report updated limits on lepton-flavor conserving and lepton-flavor violating Wilson coefficients.
Discrete Hilbert space, the Born Rule, and quantum gravity
Authors: Hsu Stephen D. H.
Published: January 2021

Quantum gravitational effects suggest a minimal length, or spacetime interval, of order of the Planck length. This in turn suggests that Hilbert space itself may be discrete rather than continuous. One implication is that quantum states with norm below some very small threshold do not exist. The exclusion of what Everett referred to as maverick branches is necessary for the emergence of the Born Rule in no collapse quantum mechanics. We discuss this in the context of quantum gravity, showing that discrete models (such as simplicial or lattice quantum gravity) indeed suggest a discrete Hilbert space with minimum norm. These considerations are related to the ultimate level of fine-graining found in decoherent histories (of spacetime geometry plus matter fields) produced by quantum gravity.
Wormhole solutions in embedding class 1 space–time
Authors: Sarkar Nayan , Sarkar Susmita , Rahaman Farook , Islam Safiqul
Published: January 2021

The present work looks for new spherically symmetric wormhole solutions of the Einstein field equations based on the well-known embedding class 1, i.e. Karmarkar condition. The embedding theorems have an interesting property that connects an [Formula: see text]-dimensional space–time to the higher-dimensional Euclidean flat space–time. The Einstein field equations yield the wormhole solution by violating the null energy condition (NEC). Here, wormholes solutions are obtained corresponding to three different redshift functions: rational, logarithm, and inverse trigonometric functions, in embedding class 1 space–time. The obtained shape function in each case satisfies the flare-out condition after the throat radius, i.e. good enough to represents wormhole structure. In cases of WH1 and WH2, the solutions violate the NEC as well as strong energy condition (SEC), i.e. here the exotic matter content exists within the wormholes and strongly sustains wormhole structures. In the case of WH3, the solution violates NEC but satisfies SEC, so for violating the NEC wormhole preserve due to the presence of exotic matter. Moreover, WH1 and WH2 are asymptotically flat while WH3 is not asymptotically flat. So, indeed, WH3 cutoff after some radial distance [Formula: see text], the Schwarzschild radius, and match to the external vacuum solution.
Short-Term Time Wind Speed Forecasting Based on Spatio-Temporal Geostatistical Approach and Kriging Method
Authors: Wang Yu , Zhu Changan , Zhao Jianghai , Wang Deji
Published: January 2021

Short-term wind speed prediction is an essential task for wind resource and wind energy planning. However, most of this literature does not take into account the spatio-termporal correlation of wind data from the geographical field. For this reason, we propose an integrated spatio-temporal kriging and functional kriging strategy to exploit such spatio-temporal correlation into the wind speed prediction. First, the deterministic trend component in wind data is estimated to be removed. The residuals are used for spatio-temporal modeling and prediction. Based on the spatio-temporal kriging framework, four spatio-temporal covariance models (product-sum model, separable exponential product model, separable and nonseparable Gneiting models) are considered which describe the spatio-temporal correlation of wind data. In particular, the flexibility of using the nonseparable Gneiting model is highlighted. More specifically, four spatio-temporal random fields are modeled from the 12 wind monitoring stations over Ireland. We also use an involved weighted least squares method for estimating parameters of the four covariance models involved in the spatio-temporal kriging strategy. We apply the fitted covariance models to generate day-ahead wind speed predictions at both observed and nonobserved locations where wind station already exist but also to nearby locations. Leave-one-out cross-validation is applied to check the significance of the difference among the four models, these spatio-temporal ordinary kriging (STOK), functional ordinary kriging (FOK) and autoregressive integrated moving average (ARIMA) methods are compared for day-ahead wind speed predictions. Forecasting results indicate that the predicting accuracy is improved almost 33.5% using FOK compared with three approaches which confirm the effectiveness of the functional kriging method in the paper.
A novel feature representation approach for single-lead heartbeat classification based on adaptive Fourier decomposition
Authors: Tan Chunyu , Zhang Liming , Wu Hau-Tieng , Qian Tao
Published: January 2021

This paper proposes a novel feature representation approach for heartbeat classification using single-lead electrocardiogram (ECG) signals based on adaptive Fourier decomposition (AFD). AFD is a recently developed signal processing tool that provides useful morphological features, which are referred as AFD-derived instantaneous frequency (IF) features and differ from those provided by traditional tools. The AFD-derived IF features, together with ECG landmark features and RR interval features, are trained by a support vector machine to perform the classification. The proposed method improves the average accuracy of the feature extraction-based methods, reaching a level comparable to deep learning but with less training data, and at the same time being interpretable for the learned features. It also greatly reduces the dimension of the feature set, which is a disadvantage of the feature extraction-based methods, especially for ECG signals. To evaluate the performance, the Association for the Advancement of Medical Instrumentation standard is applied to publicly available benchmark databases, including the MIT-BIH arrhythmia and MIT-BIH supraventricular arrhythmia databases, to classify heartbeats from the single-lead ECG. The overall performance is compared to selected state-of-the-art automatic heartbeat classification algorithms, including one-lead and even several two-lead-based methods. The proposed approach achieves superior balanced performance and real-time implementation.
Contact Analysis Within the Bi-Potential Framework Using Cell-Based Smoothed Finite Element Method
Authors: Chen Qianwei , Li Yan , Feng Zhiqiang , Chen Huijian
Published: January 2021

This paper presents a cell-based smoothed finite element method (CS-FEM) for solving two-dimensional contact problems with the bi-potential formulation. The contact force and the relative displacements on the contact surface are coupled with each other. The Uzawa algorithm, which is a local iterative technique, is used to solve the contact force. The classic Coulomb friction rule and a unilateral contact relationship are considered. There is no need to select any user-defined parameter in the whole process. Three contact states are investigated accurately, which can be stated as sticking, separating and sliding, respectively. The CS-FEM is performed with six different kinds of smoothing domains which are constructed by dividing the background element into different regions. Only boundary integrations instead of domain integral are required in the calculation, and no coordinate mapping is needed. Three numerical examples are presented to verify the effectiveness of the method. The effect of the friction coefficient for the contact is also investigated. All the obtained numerical solutions agree well with the reference values. The results produced by the CS-FEM are more accurate than those of the traditional FEM. Moreover, the CS-FEM can provide both an upper bound and a lower bound of the strain energy solutions while using different smoothing domains.
Evaluation of Rounding Functions in Nearest Neighbor Interpolation
Authors: Rukundo Olivier
Published: January 2021

A novel evaluation study of the most appropriate round function for nearest neighbor image interpolation is presented. Evaluated rounding functions are selected among the five rounding rules defined by the Institute of Electrical and Electronics Engineers IEEE 754-2008 standard. Both full- and no-reference image quality assessment metrics are used to evaluate the influence of rounding functions on nearest neighbor interpolation image quality. The concept of the number of occurrences is used to determine the percentage of achieved occurrences, which is also equivalent to the sample proportion percentage used to calculate the margin of error. Inferential statistical analysis is used to deduce from a small number of images and draw a conclusion of the performance of each rounding function on a big number of images. Experimental results are provided to demonstrate with 95% confidence the minimum performance percentage of the most appropriate rounding function.
Thermal Elastic–Plastic Analysis of Three-Dimensional Structures Using Face-Based Smoothed Point Interpolation Method
Authors: Zhong Yudong , Xie Guizhong , Hou JunJian , He Wenbin , Li Yuan
Published: January 2021

In this work, a face-based smoothed point interpolation method (FS-PIM) is formulated for three-dimensional (3D) thermal elastic-plastic analysis of structures. For this method, field functions are approximated using second order PIM shape functions and the face-based smoothing domains are used to perform the numerical integration. The material properties are considered to be temperature-dependent and the plastic behavior is studied through the Von Mises yield function. Numerical examples with different kinds of boundary conditions are investigated to verify the validity of the present method. The obtained results indicate that FS-PIM is an effective technique for the thermal elastic-plastic analysis of structures.
On r-dynamic vertex coloring of some flower graph families
Authors: Gomathi C. S. , Mohanapriya N. , Kristina Arika Indah , Dafik
Published: January 2021

Let [Formula: see text] be a simple, connected undirected graph with [Formula: see text] vertices and [Formula: see text] edges. Let vertex coloring [Formula: see text] of a graph [Formula: see text] be a mapping [Formula: see text], where [Formula: see text] and it is [Formula: see text]-colorable. Vertex coloring is proper if none of the any two neighboring vertices receives the similar color. An [Formula: see text]-dynamic coloring is a proper coloring such that [Formula: see text] min[Formula: see text], for each [Formula: see text][Formula: see text]. The [Formula: see text]-dynamic chromatic number of a graph [Formula: see text] is the minutest coloring [Formula: see text] of [Formula: see text] which is [Formula: see text]-dynamic k-colorable and denoted by [Formula: see text]. By a simple view, we exhibit that [Formula: see text], howbeit [Formula: see text] cannot be arbitrarily small. Thus, finding the result of [Formula: see text] is useful. This study gave the result of [Formula: see text]-dynamic chromatic number for the central graph, Line graph, Subdivision graph, Line of subdivision graph, Splitting graph and Mycielski graph of the Flower graph [Formula: see text] denoted by [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text] respectively.
Offline Algorithms in Low-Frequency Trading
Authors: Kelly Terence
Published: January 2021

Expectations run high for software that makes real-world decisions, particularly when money hangs in the balance. This third episode of the
Drill Bits
column shows how well-designed software can effectively
create wealth
by optimizing gains from trade in combinatorial auctions. We'll unveil a deep connection between auctions and a classic textbook problem, we'll see that clearing an auction resembles a high-stakes mutant Tetris, we'll learn to stop worrying and love an NP-hard problem that's far from intractable in practice, and we'll contrast the deliberative business of combinatorial auctions with the near-real-time hustle of high-frequency trading. The example software that accompanies this installment of
Drill Bits
implements two algorithms that clear combinatorial auctions.
Aspirin in the Prevention of Cardiovascular Disease and Cancer
Authors: Ricciotti Emanuela , FitzGerald Garret A.
Published: January 2021

More than a century after its synthesis, daily aspirin, given at a low dose, is a milestone treatment for the secondary prevention of cardiovascular disease (CVD). Its role in primary prevention of CVD is still debated. Older randomized controlled trials showed that aspirin reduced the low incidence of myocardial infarction but correspondingly increased the low incidence of serious gastrointestinal bleeds without altering mortality. More recent trials see the benefit attenuated, perhaps obscured by other cardioprotective practices, while the bleeding risk remains, especially in older patients. Indirect evidence, both preclinical and clinical, suggests that aspirin may protect against sporadic colorectal cancer and perhaps other cancers. However, further studies are still necessary to warrant the consumption of aspirin for primary prevention of CVD and cancer by apparently healthy individuals.
New Therapeutics for Ulcerative Colitis
Authors: Hirten Robert P. , Sands Bruce E.
Published: January 2021

Ulcerative colitis (UC) is a relapsing and remitting inflammatory disease of the colon with a variable course. Despite advances in treatment, only approximately 40% of patients achieve clinical remission at the end of a year, prompting the exploration of new treatment modalities. This review explores novel therapeutic approaches to UC, including promising drugs in various stages of development, efforts to maximize the efficacy of currently available treatment options, and non-medication-based modalities. Treatment approaches which show promise in impacting the future of UC management are highlighted.
Gene-Targeting Therapeutics for Neurological Disease: Lessons Learned from Spinal Muscular Atrophy
Authors: Ravi Bhavya , Chan-Cortés Michelle Harran , Sumner Charlotte J.
Published: January 2021

The last few decades have seen an explosion in identification of genes that cause monogenetic neurological diseases, as well as advances in gene-targeting therapeutics. Neurological conditions that were once considered incurable are now increasingly tractable. At the forefront is the motor neuron disease spinal muscular atrophy (SMA), historically the leading inherited cause of infant mortality. In the last 5 years, three SMA treatments have been approved by the US Food and Drug Administration (FDA): intrathecally delivered splice-switching antisense oligonucleotide (nusinersen), systemically delivered AAV9-based gene replacement therapy (onasemnogene abeparvovec), and an orally bioavailable, small-molecule, splice-switching drug (risdiplam). Despite this remarkable progress, clinical outcomes in patients are variable. Therapeutic optimization will require improved understanding of drug pharmacokinetics and target engagement in neurons, potential toxicities, and long-term effects. We review current progress in SMA therapeutics, clinical trials, shortcomings of current treatments, and implications for the treatment of other neurogenetic diseases.
Biological Aspects of Cancer Health Disparities
Authors: Freedman Jennifer A. , Al Abo Muthana , Allen Tyler A. , Piwarski Sean A. , Wegermann Kara , Patierno Steven R.
Published: January 2021

Racial and ethnic disparities span the continuum of cancer care and are driven by a complex interplay among social, psychosocial, lifestyle, environmental, health system, and biological determinants of health. Research is needed to identify these determinants of cancer health disparities and to develop interventions to achieve cancer health equity. Herein, we focus on the overall burden of ancestry-related molecular alterations, the functional significance of the alterations in hallmarks of cancer, and the implications of the alterations for precision oncology and immuno-oncology. In conclusion, we reflect on the importance of estimating ancestry, improving diverse racial and ethnic participation in cancer clinical trials, and examining the intersection among determinants of cancer health disparities.
An Investigation of the Recovery of Silicon Photovoltaic Cells by Application of an Organic Solvent Method
Authors: Tembo P. M. , Heninger M. , Subramanian V.
Published: January 2021

The treatment of photovoltaic (PV) waste is gaining traction the world over, with the recovery of valuable materials from end-of-life, or damaged and out-of-spec polycrystalline silicon PV modules. These materials are a focus of recycling. However, the current recycling practices usually involve excessive damage to PV cells that could otherwise be reused if recovered undamaged. The ability to recover undamaged PV cells, capable of reuse, would serve to further reduce the carbon footprint and cost associated with PV module manufacturing. This study focuses on the recovery of silicon PV cells from end-of-life PV modules by application of an organic solvent method. Herein, recovery tests were carried out in which silicon PV cells were recovered with minimal damage with the application of hexane as solvent. X-ray diffraction and UV–vis spectrophotometry measurements were conducted post recovery of the PV cells. The results from this study shows that the recovery of PV cells from application of hexane as the solvent could be an eco-friendly and benign approach to purse towards a strategic pathway for extending the life of recycled PV modules.
(3-Aminopropyl)trimethoxysilane Self-Assembled Monolayer as Barrier of Porous SiOCH for Electroless Cu Metallization: Optimizations of SiOCH Hydroxylation and Monolayer Functionalization
Authors: Fang Jau-Shiung , Yang Tzu-Ming , Cheng Yi-Lung , Chen Giin-Shan
Published: January 2021

Self-assembled monolayers (SAMs) are potential diffusion barriers of nanoporous carbon-doped organosilica (p-SiOCH) for Cu metallization. A concern regarding silanization of the p-SiOCH using a wet chemical process is that its dielectric properties and bonding structures could be damaged by the chemical solution used, which is rarely addressed. In this study, the capacity of various (3-aminopropyl)trimethoxysilane self-assembled monolayers (APTMS-SAMs) as a barrier of p-SiOCH for electroless Cu metallization is evaluated. The processing of hydroxylation of the p-SiOCH (for silanization) and functionalization of APTMS-SAMs (for seeding of electroless metallization) was controlled through examining dielectric properties and bond structures of the hydroxylated p-SiOCH and functionalized APTMS-SAMs. Through tailoring the wet chemical treatments, the dielectric constant, insulating capacity, and bonding structure of post-treated p-SiOCH could be preserved at the pristine states, and the APTMS-SAM fabricated turns out to be a reliable barrier thermally stable up to 500 °C, 100 °C greater than that of the p-SiOCH without an SAM barrier. The integration of electroless Cu metallization reliably with p-SiOCH using a near-zero-thickness monolayer (free of a conventional metallic barrier) in an all-wet manner will be demonstrated. However, to make this approach working, both the hydroxylation of p-SiOCH and functionalization of APTMS-SAM have to be optimized.
Soluble ACE2 as a potential therapy for COVID-19
Authors: Krishnamurthy Sudarshan , Lockey Richard F. , Kolliputi Narasaiah
Published: January 2021

Soluble angiotensin-converting enzyme 2 (sACE2) could be a therapeutic option to treat coronavirus disease 2019 (COVID-19) infection. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) utilizes ACE2 receptors on cell surfaces to gain intracellular entry, making them an ideal target for therapy. High-affinity variants of sACE2, engineered using high-throughput mutagenesis, are capable of neutralizing COVID-19 infection as decoy receptors. These variants compete with native ACE2 present on cells by binding with spike (S) protein of SARS-CoV-2, making native ACE2 on cell surfaces available to convert angiotensin II to angiotensin-1,7, thus alleviating the exaggerated inflammatory response associated with COVID-19 infection. This article explores the use of sACE2 as potential therapy for COVID-19 infection.
A dietary ketone ester mitigates histological outcomes of NAFLD and markers of fibrosis in high-fat diet fed mice
Authors: Moore Mary P. , Cunningham Rory P. , Davis Rachel A. H. , Deemer Sarah E. , Roberts Brandon M. , Plaisance Eric P. , Rector R. Scott
Published: January 2021

To our knowledge, this is the first study focusing on hepatic outcomes in response to dietary ketone ester feeding in male mice with HFD-induced NAFLD. Novel findings include that dietary ketone ester feeding ameliorates NAFLD outcomes via reductions in histological steatosis and inflammation. These improvements were beyond those observed for caloric restriction alone. Furthermore, dietary ketone ester feeding was associated with greater reductions in markers of hepatic fibrogenesis and inflammation compared with control and calorie-restricted mice.
Every breath you take: Impacts of environmental dust exposure on intestinal barrier function–from the gut-lung axis to COVID-19
Authors: Crawford Meli’sa S. , Nordgren Tara M. , McCole Declan F.
Published: January 2021

As countries continue to industrialize, major cities experience diminished air quality, whereas rural populations also experience poor air quality from sources such as agricultural operations. These exposures to environmental pollution from both rural and populated/industrialized sources have adverse effects on human health. Although respiratory diseases (e.g., asthma and chronic obstructive pulmonary disease) are the most commonly reported following long-term exposure to particulate matter and hazardous chemicals, gastrointestinal complications have also been associated with the increased risk of lung disease from inhalation of polluted air. The interconnectedness of these organ systems has offered valuable insights into the roles of the immune system and the micro/mycobiota as mediators of communication between the lung and the gut during disease states. A topical example of this relationship is provided by reports of multiple gastrointestinal symptoms in patients with coronavirus disease 2019 (COVID-19), whereas the rapid transmission and increased risk of COVID-19 has been linked to poor air quality and high levels of particulate matter. In this review, we focus on the mechanistic effects of environmental pollution on disease progression with special emphasis on the gut-lung axis.
Glucose-6-phosphate dehydrogenase deficiency contributes to metabolic abnormality and pulmonary hypertension
Authors: Varghese Mathews Valuparampil , James Joel , Rafikova Olga , Rafikov Ruslan
Published: January 2021

We have previously reported that several patients with idiopathic pulmonary hypertension (PH) had different types of G6PD deficiency. However, the role of G6PD in PH is multifactorial because G6PD is involved in controlling oxidative stress, metabolic switch, and red blood cell fragility. To delineate the contribution of G6PD to PH pathogenesis, we utilized a mouse line with decreased expression of G6PD (10% from wild-type level). We confirmed that mice with G6PD deficiency develop spontaneous pulmonary hypertension with pulmonary artery and right heart remodeling. G6PD deficiency resulted in increased free hemoglobin and activation of the p38 pathway, which we recently reported induces the development of PH in the sugen/hypoxia model via endothelial barrier dysfunction. Metabolomics analysis of G6PD deficient mice indicates the switch to alternative metabolic fluxes that feed into the pentose phosphate pathway (PPP), resulting in the upregulation of oxidative stress, fatty acid pathway, and reduction in pyruvate production. Thus, G6PD deficiency did not reduce PPP flux that is important for proliferation but activated collateral pathways at the cost of increased oxidative stress. Indeed, we found the upregulation of myo-inositol oxidase, reduction in GSH/GSSG ratio, and increased nitration in the lungs of G6PD-deficient mice. Increased oxidative stress also results in the activation of PI3K, ERK1/2, and AMPK that contribute to the proliferation of pulmonary vasculature. Therefore, G6PD deficiency has a multimodal effect, including hemolysis, metabolic reprogramming, and oxidative stress leading to the PH phenotype in mice.
A shift from glycolytic and fatty acid derivatives toward one-carbon metabolites in the developing lung during transitions of the early postnatal period
Authors: Lee Daniel D. , Park Sang Jun , Zborek Kirsten L. , Schwarz Margaret A.
Published: January 2021

During postnatal lung development, metabolic changes that coincide with stages of alveolar formation are poorly understood. Responding to developmental and environmental factors, metabolic changes can be rapidly and adaptively altered. The objective of the present study was to determine biological and technical determinants of metabolic changes during postnatal lung development. Over 118 metabolic features were identified by liquid chromatography with tandem mass spectrometry (LC-MS/MS, Sciex QTRAP 5500 Triple Quadrupole). Biological determinants of metabolic changes were the transition from the postnatal saccular to alveolar stages and exposure to 85% hyperoxia, an environmental insult. Technical determinants of metabolic identification were brevity and temperature of harvesting, both of which improved metabolic preservation within samples. Multivariate statistical analyses revealed the transition between stages of lung development as the period of major metabolic alteration. Of three distinctive groups that clustered by age, the saccular stage was identified by its enrichment of both glycolytic and fatty acid derivatives. The critical transition between stages of development were denoted by changes in amino acid derivatives. Of the amino acid derivatives that significantly changed, a majority were linked to metabolites of the one-carbon metabolic pathway. The enrichment of one-carbon metabolites was independent of age and environmental insult. Temperature was also found to significantly influence the metabolic levels within the postmortem sampled lung, which underscored the importance of methodology. Collectively, these data support not only distinctive stages of metabolic change but also highlight amino acid metabolism, in particular one-carbon metabolites as metabolic signatures of the early postnatal lung.
Recent updates on biomarkers of exposure and systemic toxicity in e-cigarette users and EVALI
Authors: McDonough Samantha R. , Rahman Irfan , Sundar Isaac Kirubakaran
Published: January 2021

Electronic nicotine delivery systems (ENDS), or e-cigarettes, are emerging tobacco products that produce aerosols by heating e-liquids, which most often consist of propylene glycol and vegetable glycerin along with various flavoring compounds, bypassing the combustion that occurs in the use of traditional tobacco cigarettes. These products have seen a drastic increase in popularity in recent years both as smoking cessation devices as well as among younger generations, due in large part to the widespread perception among consumers that e-cigs are significantly less harmful to health than traditional tobacco cigarettes. Due to the novelty of ENDS as well as their rapidly increasing use, research into biomarkers of e-cig exposure and toxicity have lagged behind their popularity, leaving important questions about their potential toxicity unanswered. Research into potential biomarkers of acute and chronic e-cig use, and e-cigarette- or vaping-associated lung injury is necessary for informing both clinical and regulatory decision-making. We aim to provide an updated review of recent research into potential circulating, genomic, transcriptomic, and epigenetic biomarkers of exposure to and toxicity of e-cigs. We additionally highlight research areas that warrant additional study to gain a better understanding of health risks associated with ENDS use, as well as to provide validation of existing data and methods for measuring and analyzing e-cig-associated biomarkers in human and animal biofluids, tissues, and cells. This review also highlights ongoing efforts within the WNY Center for Research on Flavored Tobacco for research into novel biomarkers in extracellular vesicles that may be associated with short- and long-term ENDS use.
Machine learning approaches reveal subtle differences in breathing and sleep fragmentation inPhox2b-derived astrocytes ablated mice
Authors: Silva Talita M. , Borniger Jeremy C. , Alves Michele Joana , Alzate Correa Diego , Zhao Jing , Fadda Paolo , Toland Amanda Ewart , Takakura Ana C. , Moreira Thiago S. , Czeisler Catherine M. , Otero José Javier
Published: January 2021

ML/AI classification workflows are capable of providing insight into differences between genotypes for neurophysiology research. Analytical techniques utilized in the neurophysiology community can be augmented by implementing ML/AI workflows. Random forest is a robust classification algorithm for respiratory plethysmography data. Utilization of ML/AI workflows in neurophysiology research requires heightened transparency and improved community research standards.
The role of vestibular cues in postural sway
Authors: Karmali Faisal , Goodworth Adam D. , Valko Yulia , Leeder Tania , Peterka Robert J. , Merfeld Daniel M.
Published: January 2021

Vestibular feedback is important for postural control, but little is known about the role of tilt cues vs. translation cues vs. rotation cues. We studied healthy human subjects with no known vestibular pathology or symptoms. Our findings showed that vestibular encoding of lateral translation correlated with medial-lateral postural sway, consistent with lateral translation cues contributing to balance control. This adds support to the hypothesis that vestibular noise contributes to spontaneous postural sway.
Experience-driven remodeling of S1 digit representation in awake monkeys: the challenge of comparing active and passive touch
Authors: Dione Mariama , Facchini Justine
Published: January 2021

Many studies have compared active and passive touch to understand how motor action shapes touch perception. Current views emphasize the difficulties in making such a comparison and promote investigating how motor strategies enable the filtering out of sensory inputs to reshape touch perception. Cybulska-Klosowicz et al. (Cybulska-Klosowicz A, Tremblay F, Jiang W, Bourgeon S, Meftah E-M, Chapman CE. J Neurophysiol 123: 1072–1089, 2020) suggest that primary somatosensory (S1) cortical remodeling of digit representation occurs during active touch. Here, alternative interpretations are proposed, and the relevance of studying multidigit scanning is emphasized.
Perisaccadic encoding of temporal information in macaque area V4
Authors: Schwenk Jakob C. B. , Klingenhoefer Steffen , Werner Björn-Olaf , Dowiasch Stefan , Bremmer Frank
Published: January 2021

We investigated for the first time how temporal information on very brief timescales is represented in area V4 around the time of saccadic eye movements. Overall, the responses showed an unexpectedly precise representation of time intervals. Our finding of a perisaccadic modulation of relative response amplitudes introduces a new possible correlate of saccade-related perceptual distortions of time.
Visual information increases the indirect corticospinal excitation via cervical interneurons in humans
Authors: Nakajima Tsuyoshi , Ohtsuka Hiroyuki , Irie Shun , Suzuki Shinya , Ariyasu Ryohei , Komiyama Tomoyoshi , Ohki Yukari
Published: January 2021

To date, little is known about how visual information modulates the human cervical motor systems, including the presumed interneuron (IN) circuitry. This study demonstrates that photic visual stimulation influences presumed oligosynaptic corticospinal transmission to arm motoneurons, which are mediated by cervical INs. In animals, these systems are known to be crucial for visually guided switching movements, and similar visual input systems to INs may exist in humans.
Inhibitory mechanisms control active expiration by limiting parafacial expiratory drive
Authors: Soto-Perez Jaseph
Published: January 2021

Activity of parafacial neurons that control active expiration is heavily dependent on tonic and CO2/H+-dependent excitatory and inhibitory inputs from yet poorly defined sources. Contrary to the idea that CO2/H+ disinhibits parafacial expiratory neurons, the recent work of J. D. Silva et al. (Silva JD, Oliveira LM, Souza FC, Moreira TS, Takakura AC. J Neurophysiol 123: 1933–1943, 2020) suggests that GABAergic raphe neurons preferentially limit expiratory activity during high CO2. Here, I discuss these findings and propose a model where GABAergic raphe neurons function as CO2/H+-dependent breaks on expiratory drive.
Configuration and dynamics of dominant inspiratory multineuronal activity patterns during eupnea and gasping generation in vitro
Authors: Juárez-Vidales Josué de Jesús , Pérez-Ortega Jesús , Lorea-Hernández Jonathan Julio , Méndez-Salcido Felipe , Peña-Ortega Fernando
Published: January 2021

By means of multielectrode recordings of preBötC neurons, we evaluated their configuration in normoxia and hypoxia, finding that the preBötC exhibits a scale-free configuration with a rich-club phenomenon. preBötC neurons produce multineuronal activity patterns that are highly stable but change during hypoxia. The preBötC contains a coactivating core network that exhibit a distinctive pattern of coactivation at the beginning of inspirations. These results reveal some network basis of inspiratory rhythm generation and its reconfiguration during hypoxia.