bluuebunny/crossref_metadata_2025 huggingface dataset:
Within‐ and across‐session increases in work requirement do not produce similar response output
Authors: Leon Yanerys , Wilder David , Saini Valdeep
Published: February 2021

Demand curve fitting is a method of data analysis for interpreting reinforcer consumption. These methods were established and validated by examining increases in unit price (UP) across sessions. An alternative experimental preparation is the progressive‐ratio (PR) schedule in which schedule requirements increase within a session. Although PR schedules provide an efficient alternative to traditional evaluations of UP, using demand curves to interpret data obtained via PR schedules has not been systematically evaluated in applied contexts. In this study, the experimenters compared demand curves constructed based on across‐ and within‐session increases in UP and evaluated correspondence between the two methods. Results indicated poor correspondence between demand curves constructed with the two methods. Furthermore, within‐session measures of responding suggest that higher rates of problem behavior and longer durations of postreinforcement pauses were more likely under PR schedules than fixed‐ratio schedules. Results are discussed in terms of implications for clinical application.
FoxP1 is a transcriptional repressor associated with cancer cachexia that induces skeletal muscle wasting and weakness
Authors: Neyroud Daria , Nosacka Rachel L. , Callaway Chandler S. , Trevino Jose G. , Hu Hui , Judge Sarah M. , Judge Andrew R.
Published: February 2021

Background

Skeletal muscle wasting is a devastating consequence of cancer that affects up to 80% of cancer patients and associates with reduced survival. Herein, we investigated the biological significance of Forkhead box P1 (FoxP1), a transcriptional repressor that we demonstrate is up‐regulated in skeletal muscle in multiple models of cancer cachexia and in cachectic cancer patients.

Methods

Inducible, skeletal muscle‐specific FoxP1 over‐expressing (FoxP1iSkmTg/Tg) mice were generated through crossing conditional Foxp1a transgenic mice with HSA‐MCM mice that express tamoxifen‐inducible Cre recombinase under control of the skeletal muscle actin promoter. To determine the requirement of FoxP1 for cancer‐induced skeletal muscle wasting, FoxP1‐shRNA was packaged and targeted to muscles using AAV9 delivery prior to inoculation of mice with Colon‐26 Adenocarcinoma (C26) cells.

Results

Up‐regulation of FoxP1 in adult skeletal muscle was sufficient to induce features of cachexia, including 15% reduction in body mass (P < 0.05), and a 16–27% reduction in skeletal muscle mass (P < 0.05) that was characterized by a 20% reduction in muscle fibre cross‐sectional area of type IIX/B muscle fibres (P = 0.020). Skeletal muscles from FoxP1iSkmTg/Tg mice also showed significant damage and myopathy characterized by the presence of centrally nucleated myofibres, extracellular matrix expansion, and were 19–26% weaker than controls (P < 0.05). Transcriptomic analysis revealed FoxP1 as a potent transcriptional repressor of skeletal muscle gene expression, with enrichment of pathways related to skeletal muscle structure and function, growth signalling, and cell quality control. Because FoxP1 functions, at least in part, as a transcriptional repressor through its interaction with histone deacetylase proteins, we treated FoxP1iSkmTg/Tg mice with Trichostatin A, and found that this completely prevented the loss of muscle mass (p = 0.007) and fibre atrophy (P < 0.001) in the tibialis anterior. In the context of cancer, FoxP1 knockdown blocked the cancer‐induced repression of myocyte enhancer factor 2 (MEF2)‐target genes critical to muscle differentiation and repair, improved muscle ultrastructure, and attenuated muscle fibre atrophy by 50% (P < 0.05).

Conclusions

In summary, we identify FoxP1 as a novel repressor of skeletal muscle gene expression that is increased in cancer cachexia, whose up‐regulation is sufficient to induce skeletal muscle wasting and weakness, and required for the normal wasting response to cancer.
The role of recipient myosteatosis in graft and patient survival after deceased donor liver transplantation
Authors: Czigany Zoltan , Kramp Wiebke , Lurje Isabella , Miller Hannah , Bednarsch Jan , Lang Sven Arke , Ulmer Tom Florian , Bruners Philipp , Strnad Pavel , Trautwein Christian , von Websky Martin Wolfgang , Tacke Frank , Neumann Ulf Peter , Lurje Georg
Published: February 2021

Background

Myosteatosis is associated with perioperative outcomes in orthotopic liver transplantation (OLT). Here, we investigated the effects of body composition and myosteatosis on long‐term graft and patient survival following OLT.

Methods

Clinical data from 225 consecutive OLT recipients from a prospective database were retrospectively analysed (May 2010 to December 2017). Computed tomography‐based lumbar skeletal muscle index (SMI) (muscle mass) and mean skeletal muscle radiation attenuation (SM‐RA) (myosteatosis) were calculated using a segmentation tool (3D Slicer). Patients with low skeletal muscle mass (low SMI) and myosteatosis (low SM‐RA) were identified using predefined and validated cut‐off values.

Results

The mean donor and recipient age was 55 ± 16 and 54 ± 12 years, respectively. Some 67% of the recipients were male. The probability of graft and patient survival was significantly lower in patients with myosteatosis compared with patients with higher SM‐RA values (P = 0.011 and P = 0.001, respectively). Low skeletal muscle mass alone was not associated with graft and patient survival (P = 0.273 and P = 0.278, respectively). Dividing the cohort into quartiles, based on the values of SMI and SM‐RA, resulted in significant differences in patient but not in graft survival (P = 0.011). Even though multivariable analysis identified low SM‐RA as an important prognostic marker (hazard ratio: 2.260, 95% confidence interval: 1.177–4.340, P = 0.014), myosteatosis lost its significance when early mortality (90 days) was excluded from the final multivariable model. Patients with myosteatosis showed significantly higher all‐cause mortality and in particular higher rates of deaths due to respiratory and septic complication (P = 0.002, P = 0.022, and P = 0.049, respectively).

Conclusions

Preoperative myosteatosis may be an important prognostic marker in patients undergoing deceased donor liver transplantation. The prognostic value of myosteatosis seems to be particularly important in the early post‐operative phase. Validation in prospective clinical trials is warranted.
Contribution of protein A step towards cost of goods for continuous production of monoclonal antibody therapeutics
Authors: Bansode Vikrant , Gupta Paridhi , Kateja Nikhil , Rathore Anurag S
Published: February 2021

BACKGROUND

Monoclonal antibodies (mAbs) presently dominate the biotherapeutic market. However, biotherapeutics in general, and mAbs in particular, are expensive therapies and outside the realm of affordability for most of the world. In an attempt to lower their cost of manufacturing, a novel in‐house non‐protein A continuous platform has recently been reported for mAb purification. In this paper, we perform an in‐depth evaluation of the process economics to assess the impact of removing the protein A step on the cost of goods (COGs).

RESULTS

The non‐protein A platform was found to result in significant savings in COGs at about 23% when comparing both platforms in batch mode. Conversion of the non‐protein A platform from batch to continuous mode led to a further increase in these savings with about 39% gains in COGs over the conventional protein A platform.

CONCLUSIONS

The non‐protein A purification platform offers a viable alternative to the standard protein A platform and can be considered when setting up a new facility. The continuous non‐protein A platform can especially be considered given the flexibility of the setup and the utility at both small and large scales. © 2021 Society of Chemical Industry
‘Do language and culturereallymatter?’: A trans‐disciplinary investigation of cultural diversity in genetic counseling in Hong Kong
Authors: Zayts‐Spence Olga , Fung Jasmine L. F. , Chung Brian H. Y.
Published: February 2021

In this paper, we present evidence that in counseling culturally diverse patients, differences in spoken language and cultural beliefs of the patients and genetic counseling professionals do not necessarily impede successful counseling. We also highlight sociocultural factors, including socioeconomic background and genetic literacy, that may impact communication in multicultural/ multilingual contexts or when languages other than English are used. While genetic counseling is not short of insights and practical guidelines on sociocultural and language issues, and increasingly, research that employs interviews and surveys, empirical research that draws onauthenticinteractional data (in the form of video‐ and audio‐recorded interactions and their transcripts) is limited. Our goal here is to assess how needs are communicated among a diverse population using an innovative empirical approach that builds on the analysis of transcribed interactions as the primary data and optimizes trans‐disciplinary expertise in linguistics, genetics and genetic counseling. We present data from 42 genetic counseling encounters addressing Sudden Arrhythmic Death Syndrome (SADS) in Hong Kong. We demonstrate the value of thesituatedanalysis of genetic counseling, which focuses on those junctures in the interaction where participants orient to their different linguistic and/or cultural backgrounds asrelevantto the ongoing interaction. We further show that participants draw on various interactional resources to negotiate and resolve possible differences or misunderstandings. We highlight the advantages of incorporating authentic (i.e., non‐simulated) data into the training of genetic counselors to increasecultural awarenessand to provide communication tools (i.e., interactional strategies) they can draw on in their counseling practice.
Uptake of moss‐derived human recombinant GAA in Gaa−/− mice
Authors: Hintze Stefan , Dabrowska‐Schlepp Paulina , Berg Birgit , Graupner Alexandra , Busch Andreas , Schaaf Andreas , Schoser Benedikt , Meinke Peter
Published: February 2021

Pompe disease, an autosomal recessive lysosomal storage disorder, is caused by deficiency of lysosomal acid alpha‐glucosidase (GAA). On cellular level, there is lysosomal‐bound and free accumulation of glycogen and subsequent damage of organelles and organs. The most severe affected tissues are skeletal muscles and heart. The only available treatment to date is an enzyme replacement therapy (ERT) with alglucosidase alfa, a recombinant human GAA (rhGAA) modified with mannose‐6‐phosphate (M6P), which is internalized via M6P‐mediated endocytosis. There is an unmet need to improve this type of therapy, especially in regard to skeletal muscle. Using different tissue culture models, we recently provided evidence that a moss‐derived nonphosphorylated rhGAA (moss‐GAA), carrying a glycosylation with terminal N‐acetylglucosamine residues (GnGn), might have the potential to improve targeting of skeletal muscle. Now, we present a pilot treatment of Gaa−/− mice with moss‐GAA. We investigated general effects as well as the uptake into different organs following short‐term treatment. Our results do confirm that moss‐GAA reaches the target disease organs and thus might have the potential to be an alternative or complementary ERT to the existing one.
Dynamics of ecosystem carbon stocks in a chronosequence of nitrogen‐fixing Nepalese alder (Alnus nepalensis D. Don.) forest stands in the central Himalayas
Authors: Joshi Rajendra Kr. , Garkoti Satish Chandra
Published: February 2021

Nitrogen‐fixing Nepalese alder (Alnus nepalensis D. Don.) is a rapidly‐growing pioneer tree species that often forms pure stands in areas affected by landslides, but also occurs mixed with other late‐successional species in the central Himalayas. In this study, we assessed the distribution of carbon in vegetation and soil in a chronosequence of A. nepalensis (3–270 years old) forest stands and evaluated its correlation with the stand and alder total basal area (TBA). The study was conducted in six different naturally occurring forest stands in a chronosequence, viz., alder‐early regenerating (AER), alder‐late regenerating (ALR), alder young‐mixed (AYM), alder mature‐oak (Quercus leucotrichophora) mixed (AMOM), alder mature‐rhododendron (Rhododendron arboreum) mixed (AMR), and alder old‐oak (Q. leucotrichophora) mixed (AOOM) forests. The chronosequence consisted of three young unreserved, AER, ALR, and AYM (age 3–25) and three older reserved, AMOM, AMR, and AOOM (age 80–270) stands. We used structural equation modelling (SEM) to quantify the contribution of various carbon pools on ecosystem carbon stock. Forest carbon stock significantly increased (p < 0.05) with forest age and TBA, indicating that succession is the driving factor of the forest ecosystem processes, carbon accumulation, and therefore, change in vegetation biomass carbon and soil carbon in the chronosequence of A. nepalensis forests. Total vegetation biomass carbon (tree, shrubs, herbs, and litter) contained ~12.54–289.85 Mg ha−1 (79.11–57.77% total carbon stock), and soil carbon (depths of 0–10 cm in AER, 0–30 cm in AYM, 0–100 cm in remaining forest stands) contained ~3.31–210.13 Mg ha−1 (20.8–42% total carbon stock) and positively increased with stand and A. nepalensis TBA. The tree layer biomass carbon stock was considerably higher than the understory (shrubs, herbs, and forest floor). The soil carbon stock was reported to be influenced by the successional stages. Therefore, these findings reflect that the A. nepalensis forest development in the central Himalayas lead to storage of large amount of carbon stock in both plant biomass and soil.
Ageing of PBF‐Grade Poly(Phenylene Sulfide) Powder and its Effect on Critical Printability Properties
Authors: Chatham Camden A. , Das Arit , Long Timothy E. , Bortner Michael J. , Williams Christopher B.
Published: February 2021

Poly(phenylene sulfide) (PPS) is a high‐performance polymer suiting the needs of powder bed fusion (PBF) early‐adopter industries. Although there are many benefits to PBF's powder bed‐based, one drawback is thermal ageing of the powder not incorporated into printed parts. Ideally, unfused powder can be reused in future builds; however, it is unlikely that critical printability properties of the thermally aged powder will remain unchanged. Changes in properties lead to either limited reuse through a practice of mixing used and new powder, or elimination of all powder after each build. In this paper, the authors report effects of thermal ageing in simulated printing conditions on properties of PPS critical to PBF processing. PBF‐grade PPS powder is exposed to process‐mimicking conditions. Properties relevant to the three PBF manufacturing process sub‐functions are assessed for the aged powders. Single‐layer prints are made using aged powder to observe polymer‐PBF interactions ad machina. Significant and systematic deviations from the as‐received state of the powder are observed for thermal and coalescence related properties with increasing exposure time and temperature. These changes are interpreted both in terms of physical and chemical changes in PPS and in terms of how these changes may impact the PBF printing process.
Properties of hyperbolic sinusoidal Gaussian beam propagating through strong atmospheric turbulence
Authors: Bayraktar Mert
Published: February 2021

This paper presents evolution of hyperbolic sinusoidal Gaussian (HSG) beam and its point‐like scintillation while propagating through turbulent atmosphere. We benefit from random phase screen approach to evaluate received field and scintillation. We see that astigmatic beams, which source parameters are not equal, are resistive against atmosphere considering intensity distribution. In case of scintillation, all selected HSG beams have less scintillation index than Gauss beam. In addition, astigmatism decreases scintillation at constant Gaussian source size. We anticipate that optical wireless communication devices can be designed using our outputs.
Development and preclinical evaluation of a patient‐specific high energy x‐ray phase sensitive breast tomosynthesis system
Authors: Ghani Muhammad U. , Wu Xizeng , Fajardo Laurie L. , Jing Zhengxue , Wong Molly D. , Zheng Bin , Omoumi Farid , Li Yuhua , Yan Aimin , Jenkins Peter , Hillis Stephen L. , Linstroth Laura , Liu Hong
Published: February 2021

Background

This article reports the first x‐ray phase sensitive breast tomosynthesis (PBT) system that is aimed for direct translation to clinical practice for the diagnosis of breast cancer.

Purpose

To report the preclinical evaluation and comparison of the newly built PBT system with a conventional digital breast tomosynthesis (DBT) system.

Methods and materials

The PBT system is developed based on a comprehensive inline phase contrast theoretical model. The system consists of a polyenergetic microfocus x‐ray source and a flat panel detector mounted on an arm that is attached to a rotating gantry. It acquires nine projections over a 15° angular span in a stop‐and‐shoot manner. A dedicated phase retrieval algorithm is integrated with a filtered back‐projection method that reconstructs tomographic slices. The American College of Radiology (ACR) accreditation phantom, a contrast detail (CD) phantom and mastectomy tissue samples were imaged at the same glandular dose levels by both the PBT and a standard of care DBT system for image quality characterizations and comparisons.

Results

The PBT imaging scores with the ACR phantom are in good to excellent range and meet the quality assurance criteria set by the Mammography Quality Standard Act. The CD phantom image comparison and associated statistical analyses from two‐alternative forced‐choice reader studies confirm the improvement offered by the PBT system in terms of contrast resolution, spatial resolution, and conspicuity. The artifact spread function (ASF) analyses revealed a sizable lateral spread of metal artifacts in PBT slices as compared to DBT slices. Signal‐to‐noise ratio values for various inserts of the ACR and CD phantoms further validated the superiority of the PBT system. Mastectomy sample images acquired by the PBT system showed a superior depiction of microcalcifications vs the DBT system.

Conclusion

The PBT imaging technology can be clinically employed for improving the accuracy of breast cancer screening and diagnosis.
Improving linac integrated cone beam computed tomography image quality using tube current modulation
Authors: Stankovic Uros , Ploeger Lennert S. , Sonke Jan‐Jakob
Published: February 2021

Purpose

Linac integrated cone beam CT (CBCT) scanners have become widespread tool for image guidance in radiotherapy. The current implementation uses constant imaging fluence across all the projection angles, which leads to anisotropic noise properties and suboptimal image quality for noncircular symmetric objects. Tube current modulation (TCM) is widely used in conventional CT. The purpose of this work was to implement TCM on a linac integrated CBCT scanner and evaluate its impact on image quality under varying scatter conditions and scatter correction strategies.

Methods

We have implemented TCM on a nonclinical Elekta Versa HD linear accelerator with enhanced x‐ray generator functionality including pulse width modulation. The pulse width was modulated using two Arduino programmable microcontrollers: one placed on the kV arm to measure the projection angle and the other connected to the kV generator control board to vary x‐ray pulse width as function of gantry angle and precalculated transmission. An in‐house developed phantom with a ratio of the left–right to anterior–posterior path length of 1.85:1 was scanned. Image quality was determined using the anisotropicity of the 2D noise power spectra (NPS) in the transverse plane and the contrast‐to‐noise ratio (CNR). In addition, to determine the impact of scatter on the applicability of the TCM method we have modified the generated scatter using three different collimators in the cranio‐caudal direction as well as with and without an antiscatter grid (ASG).

Results

Application of the TCM led to 30–78% reduction of the angular anisotropicity of the NPS in the transverse plane. The amount of reduction depended on the scatter conditions, with lower values corresponding to higher scatter conditions. The same was true for the CNR: when scatter contribution was low (presence of an ASG or very aggressive collimation) the CNR was improved by about 30%, while in high scatter conditions the CNR was improved by about 12%.

Conclusions

TCM has the potential to improve CBCT image quality, but this depends on the amount of detected x‐ray scatter.
A novel primal‐dual eigenstress‐driven method for shakedown analysis of structures
Authors: Li Kai , Cheng Gengdong , Wang Yu , Liang Yuan
Published: February 2021

The shakedown load of elastoplastic structures under multiple variable loading is an important factor in structural design and integrity analysis. In classical plasticity shakedown analysis is an essential and challenging problem. Most existing methods are based on the solution of super large‐scale mathematical programming, basis reduction or mechanics insight method which have their own limitations in practical engineering problem. In the present study, the proposed method explores the Karush–Kuhn–Tucker (KKT) conditions and the physical reinterpretation of its primal‐dual variables of the Melan's lower bound theorem, and establishes the relation of the primal‐dual variables in finite element formulation. Based on the primal‐dual theory, the primal‐dual eigenstress‐driven method is proposed which is a two‐level nested algorithm: the inner level is the eigenstress‐driven incremental algorithm for constructing the beneficial residual stress field and calculating the safe multiplier and the outer level is the load multiplier descent algorithm for searching the shakedown multiplier. For the purpose of algorithm's universality, the proposed algorithm is fully integrated with the commercial finite element software ANSYS APDL without special optimization solvers, which is well suited for large‐scale practical engineering structures. Several numerical examples are provided to demonstrate the accuracy and efficiency of the proposed algorithm.
You′re brave, I′ll be your friend: Children's evaluations of peers with cancer
Authors: Nash Jane Gradwohl , Weinberger Nanci
Published: February 2021

The focus of this study was to explore children's evaluations of healthy peers and peers with cancer. A racially and ethnically diverse group of fourth‐ and fifth‐grade children (n = 109) viewed a story about a child engaged in a physically challenging rock climbing tower activity at camp. The way the child (healthy or with cancer) ascended and descended the climbing tower (independently or with assistance) was manipulated. Assessment from the participants included their evaluations of the climber (regarding peer acceptance and trait favorability) and their knowledge of cancer. Also, participants’ own behavioral difficulties were assessed by their parents. Results showed that when the climber was healthy, peer acceptance and bravery were higher when ascending independently compared to doing so with assistance. In contrast, the climber with cancer was accepted as a friend and deemed brave, regardless of climbing method. Results revealed that participants had high levels of knowledge about cancer and were likely to know that children with cancer can play outside if they saw just that in the story they heard. These findings suggest that presenting children with cancer engaging in authentic and destigmatizing activities can impact how they are perceived by their potential peers and thus could be an important component for school re‐entry programs.
Congenital central hypoventilation syndrome and ventilatory responses during cardiopulmonary exercise testing
Authors: Sunkonkit Kanokkarn , Chiang Jackie , Moraes Theo J. , To William , Schneiderman Jane E. , Cifra Barbara , Amin Reshma
Published: February 2021

Background

Previous studies have shown evidence of hypoxemia and hypercapnia during cardiopulmonary exercise test (CPET) evaluation in children with congenital central hypoventilation syndrome (CCHS). However, there are no longitudinal studies which compared CPET findings to polysomnogram (PSG) or PHOX2B mutation, to date.

Objectives

To describe the longitudinal CPET findings in a cohort of children with CCHS and correlate the findings to the PSG results.

Methods

This retrospective study was conducted in children with CCHS followed in the Long‐term Ventilation Program at SickKids, Toronto, Canada between September, 2013 and January, 2020. CCHS genetic mutation, age of diagnosis, ventilatory support, family history, disease associations of CCHS, CPETs, and PSG parameters were recorded and analyzed.

Results

A total of nine patients with CCHS (46 CPETs and 46 PSGs) were enrolled. Four (44.4%) children had polyalanine repeat mutations. The mean (SD) age at the time of diagnosis and duration of ventilatory usage were 3.2 ± 3.4 years and 11.5 ± 2.8 years, respectively. All abnormal CPETs had hypercapnia in at least 1 phase of the exercise test. Hypercapnia (12/46; 26.1%) at peak of exercise was the most common abnormality. None of the children experienced an oxygen desaturation below 90%. End‐tidal CO2 (PetCO2) at rest and at peak exercise in the CPETs were significantly correlated with PSG TcCO2 while PetCO2 at anaerobic threshold was correlated with CO2 in pre‐PSG capillary blood gas.

Conclusion

Nocturnal hypoventilation may impact the CPET results in CCHS children. Serial CPETs should be considered standard clinical care for all CCHS children.
Transcutaneous monitoring of diaphragm activity as a measure of work of breathing in preterm infants
Authors: van Leuteren Ruud W. , de Waal Cornelia G. , Hutten Gerard J. , de Jongh Frans H. , van Kaam Anton H.
Published: February 2021

Objective

Monitoring work of breathing (WOB) is important to assess the pulmonary condition and adjust respiratory support in preterm infants. Conventional WOB measurement (esophageal pressure, tidal volume) is invasive and we hypothesized that monitoring diaphragm activity could be a noninvasive alternative to estimate WOB. The objective was to determine the correlation between conventional WOB measures and diaphragm activity, in preterm infants.

Methods

WOB and diaphragm activity, measured with transcutaneous electromyography (dEMG), were simultaneously recorded at different nasal continuous positive airway pressure (nCPAP) levels. During a 30‐s recording at each nCPAP level, dEMG parameters, inspiratory WOB (WOBi), and pressure time product (PTPin) were calculated per breath. The correlation coefficient between WOB‐ and dEMG‐measures was calculated using single breaths and after aggregating all breaths into deciles of incremental WOBi.

Results

Fifteen preterm infants were included (median gestational age, 28 weeks). Single‐breath analysis showed a poor median correlation of 0.27 (interquartile range [IQR], 0.03 to 0.33) and 0.08 (IQR, −0.03 to 0.28), respectively, for WOBi and PTPin with peak diaphragmatic activity (dEMGpeak). A modest median correlation coefficient of 0.65 (IQR, 0.13 to 0.79) and 0.43 (IQR, −0.33 to 0.69) was found for, respectively, WOBi and PTPin with dEMGpeak in the aggregated analysis.

Conclusion

Diaphragm activity showed a modest correlation with WOBi and PTPin in an aggregated analysis. This finding warrants further studies in infants with more significant lung disease.
Upregulation of neuropeptides and obstructive airway disorder in infancy: A review with focus on post‐RSV wheezing and NEHI
Authors: Wang Bin , Cardenas Monica , Bedoya Mariana , Colin Andrew A. , Rossi Giovanni A.
Published: February 2021

Obstructive airway disorders, common in infancy and early childhood, include some entities that are recognized to have neuro immune mediators as their underlying pathogenetic mechanisms. The best characterized example amongst post‐viral wheezing phenotypes is the disorder that follows respiratory syncytial virus (RSV) infection and leads to intermittent, long‐term wheezing. The underlying mechanisms of the airway reactivity related to RSV infection have been extensively studies and are associated with dysregulation of the nonadrenergic‐noncholinergic (NANC) system, via upregulation of neurotransmitters, typically Substance P. Neuroendocrine hyperplasia of infancy (NEHI), while a less common entity, is a disorder characterized by more severe and long‐term obstructive airway disease. NEHI is pathophysiologically characterized by abundance of neuroendocrine cells in the airways containing the neuroimmune mediator bombesin, the release of which is presumed to be the driver of the persistent small airway obstruction and functional air‐trapping. Here we review the NANC and neuroendocrine cells, the neurotransmitter systems and their studied roles in pulmonary diseases with a focus on their role in lung development, and subsequent various pediatric lung diseases. We focus on the juxtaposition of the separate neuroimmune mechanisms underlying the pathogenesis of post‐RSV recurrent wheezing and NEHI's persistent small airway obstruction. We finally propose a unifying concept of neuropeptides in obstructive disorders that may encompass these two entities and possibly others.
Tropopause‐penetrating convection in the extratropics: A satellite‐based investigation for the year 2018
Authors: Shou Yi‐Xuan , Lu Feng , Wang Fu
Published: February 2021

Tropopause‐penetrating convection (or “overshooting convection” [OC]) is defined as a meso‐to‐microscale stratosphere–troposphere exchange process caused by deep convection. OC plays an important role in stratosphere–troposphere exchange and in producing turbulence. Compared with the tropics, the characteristics of OC in the extratropics are poorly understood. To this end, a high‐resolution and objective satellite‐based OC identification and classification algorithm was developed. In the algorithm, a machine learning method was utilized to derive tropopause height directly from satellite observations to ensure a high level of consistency between tropopause and cloud top height variations. By studying the climatology of OCs, including geographic distribution, vertical extent, and seasonal and diurnal variation, as well as their linkage with turbulence in the extratropics in 2018 based on Fengyun‐4A geostationary meteorological satellite data, it was found that most OCs in the extratropics have relatively shallow vertical extents and are more likely to occur over complex topography within the cyclonic curvature side of subtropical jets near the exit region, with a total frequency lower than 0.2%. They showed significant seasonal and diurnal variation. OCs in the Northern Hemisphere occurred most frequently during spring and summer and peak in the afternoon, while those in the Southern Hemisphere were more likely to occur in winter and spring, and with the highest likelihood in the early morning. Typical synoptic conditions for the occurrence of OCs in the mid–high latitudes of the Northern Hemisphere in the summer months included low‐level easterly flows, increased moisture symmetric instability, upper cold trough (or cold vortex), and a subtropical westerly jet. Under this large‐scale flow pattern, moderate‐to‐greater turbulence was often found to occur within or about 200 km away from the core convective area. The stronger the penetrating convection, the greater the probability of moderate‐to‐greater turbulence.
Recovery of Diadromous Fishes: A Kennebec River Case Study
Authors: Wippelhauser Gail
Published: February 2021

The lack of safe, timely, and effective fish passage at dams remains a major impediment to the restoration of diadromous fish species to their historic range and abundance. Because fish passage facilities are often ineffective, dam removal has increasingly been used to restore diadromous species. However, few quantitative studies have assessed the response of fishes to dam removal. This paper documents the long‐term response of multiple fish species in the Kennebec River, Maine, to the removal of two hydropower dams and the installation of upstream fish passage facilities that restored access to historic habitat. Edwards Dam was removed in 1999, and Fort Halifax Dam was removed in 2008. Counts of river herring (Alewife Alosa pseudoharengus and Blueback Herring A. aestivalis), American Shad A. sapidissima, and Striped Bass Morone saxatilis at upstream dams confirmed that these species quickly recolonized the 27‐km, free‐flowing segment of the Kennebec River that became accessible after Edwards Dam was removed. Average counts of river herring increased by 228% after the removal of Edwards Dam and by 1,425% after the removal of Fort Halifax Dam. However, access to a substantial amount of habitat in the Kennebec River is blocked by ineffective passage at the lowermost dam.
Resumption of Anadromy or Straying? Origins of Sockeye Salmon in the Elwha River
Authors: Quinn Thomas P. , Pess George R. , Sutherland Ben J. G. , Brenkman Samuel J. , Withler Ruth E. , Flynn Kelsey , Beacham Terry D.
Published: February 2021

When barriers to migration are removed, anadromous fishes from other rivers may colonize newly accessible habitat or landlocked forms of the species may resume anadromy if conditions allow. For example, two large hydroelectric dams on the Elwha River, Washington, were removed between 2011 and 2014 to restore populations of Pacific salmon Oncorhynchus spp. after a century of isolation. Immediately prior to and following dam removal (2010–2017), upstream‐migrating adult Sockeye Salmon Oncorhynchus nerka were sampled, and DNA was extracted and compared with samples from the local Lake Sutherland population (above the lower dam’s former location) and a coastwide genetic baseline to determine the probable origin of each fish. Genetic analysis indicated that none of the 45 Sockeye Salmon sampled had originated from the local population or other populations nearby in the genetic baseline, and only a single fish originated from the abundant and proximate Fraser River populations. The strays reflected two different sources and processes: 22 were from the west coast of Vancouver Island (all in 2015, when these populations were very abundant and encountered conditions unfavorable for upstream migration in their natal system) and another 22 assigned to more northerly populations, mostly to riverine populations from the Stikine River. Test fishery samples collected in the Strait of Juan de Fuca contained very few fish with assignments similar to these northern rivers. It is not clear whether these individuals originated from the distant riverine populations or from a closer population not in the baseline that resembles them genetically. Taken together, the findings indicate that the genetic composition of any future population in the Elwha River may reflect signatures from diverse sources and subsequent selection in the new habitat.
Relationship between ophthalmic artery Doppler and maternal cardiovascular function
Authors: Gibbone E. , Sapantzoglou I. , Nuñez‐Cerrato M. E. , Wright A. , Nicolaides K. H. , Charakida M.
Published: February 2021

Objective

In mid‐gestation, the finding of an increase in the ophthalmic artery second to first peak of systolic velocity ratio (PSV ratio) provides useful prediction of subsequent development of pre‐eclampsia (PE). The objective of this study of an unselected population at 19–23 weeks' gestation was to gain a better understanding of the factors that influence ophthalmic artery Doppler by examining the possible association between the PSV ratio and maternal cardiovascular function.

Methods

This was a prospective observational study in women attending for a routine hospital visit at 19 + 1 to 23 + 3 weeks' gestation. This visit included assessment of flow velocity waveforms from the maternal ophthalmic arteries and assessment of maternal cardiovascular function. The following nine cardiovascular indices were examined: E/A ratio; E/e′ ratio; myocardial performance index; global longitudinal systolic strain; left ventricular ejection fraction; peripheral vascular resistance; left ventricular cardiac output; left ventricular mass indexed for body surface area; and mean arterial pressure. The ophthalmic artery PSV ratio and the nine cardiovascular indices were converted to either log10 multiples of the median (MoM) values or deviations from the median (deltas) values after adjustment for maternal characteristics and elements of medical history. Regression analysis was then used to examine the significance of the association between PSV ratio delta and MoM or delta values of each cardiovascular index in the total population and in the subgroup that developed PE.

Results

The study population of 2853 pregnancies contained 76 (2.7%) that developed PE. In the total population, there were significant but weak associations between the PSV ratio and most of the cardiovascular indices, with r‐values of < 0.1, except for mean arterial pressure with r = 0.178. In the subgroup that developed PE, a moderately strong association between the PSV ratio and left ventricular mass indexed for body surface area was noted (r = 0.308).

Conclusions

The findings of this study suggest that Doppler assessment of PSV ratio in the ophthalmic artery provides information about peripheral vascular status. The increase in PSV ratio in women who develop PE is associated with increased afterload and an increase in left ventricular thickness. © 2021 International Society of Ultrasound in Obstetrics and Gynecology
The age of bioinspired molybdenum‐involved nanozymes: Synthesis, catalytic mechanisms, and biomedical applications
Authors: Zu Yan , Yao Huiqin , Wang Yifan , Yan Liang , Gu Zhanjun , Chen Chunying , Gao Lizeng , Yin Wenyan
Published: February 2021

Molybdenum (Mo), as a nontoxic and low‐cost transition metal, has been employed for synthesis of various Mo‐based nanomaterials with unique structures and physicochemical features to achieve various properties. Especially, bioinspired Mo‐based nanomaterials show great potential for the construction of novel nanozyme catalysts due to their variable oxidation states. Overcoming drawbacks of natural enzymes, bioinspired Mo‐based nanozymes not only provide effective catalytic sites or multivalent elements to mimic natural enzymes, but also present multiple functions for interfacing with various biomicroenvironments. Construction of vast Mo‐based nanozymes has attracted enormous interest in biomedicine. Exogenous/endogenous stimuli enable the user to tailor the catalytic activities of Mo‐based nanozymes. Additionally, tunable physicochemical properties also have a significant influence on their enzyme‐like activity. In this review, we comprehensively summarize typical synthesis strategies, catalytic mechanism, and types of enzyme‐like activity of the bioinspired Mo‐based nanozymes. We mainly highlight desired merits of bioinspired Mo‐based nanozymes related to tunable enzyme‐like activity, stability, and multifunctionality through regulating their physicochemical properties. Furthermore, we intend to discuss their biomedical applications in biosensing and detection, oncotherapy, and combating bacteria. Finally, current challenges and future perspectives of the Mo‐based nanozymes are also proposed.
Toxicity prediction based on artificial intelligence: A multidisciplinary overview
Authors: Pérez Santín Efrén , Rodríguez Solana Raquel , González García Mariano , García Suárez María Del Mar , Blanco Díaz Gerardo David , Cima Cabal María Dolores , Moreno Rojas José Manuel , López Sánchez José Ignacio
Published: February 2021

The use and production of chemical compounds are subjected to strong legislative pressure. Chemical toxicity and adverse effects derived from exposure to chemicals are key regulatory aspects for a multitude of industries, such as chemical, pharmaceutical, or food, due to direct harm to humans, animals, plants, or the environment. Simultaneously, there are growing demands on the authorities to replace traditional in vivo toxicity tests carried out on laboratory animals (e.g., European Union REACH/3R principles, Tox21 and ToxCast by the U.S. government, etc.) with in silica computational models. This is not only for ethical aspects, but also because of its greater economic and time efficiency, as well as more recently because of their superior reliability and robustness than in vivo tests, mainly since the entry into the scene of artificial intelligence (AI)‐based models, promoting and setting the necessary requirements that these new in silico methodologies must meet. This review offers a multidisciplinary overview of the state of the art in the application of AI‐based methodologies for the fulfillment of regulatory‐related toxicological issues.

This article is categorized under:

Data Science > Chemoinformatics

Data Science > Artificial Intelligence/Machine Learning
Short‐term wind speed multistep combined forecasting model based on two‐stage decomposition and LSTM
Authors: Liao Xuechao , Liu Zhenxing , Deng Wanxiong
Published: February 2021

In order to better extract and study the characteristics of the wind speed in time‐domain and frequency‐domain, so as to solve the time‐domain randomness and frequency‐domain complexity problems of the wind speed signal, a combined short‐term prediction model (WD‐VMD‐DLSTM‐AT), which is based on two‐stage decomposition (WD + VMD), double long‐short‐term memory network (DLSTM) and attention mechanism (AT), is proposed; on this basis, a multi‐input multiple output (MIMO) codec model based on attention mechanism (MMED‐AT) is proposed for multiple short‐term wind speed step forecast. Through experimental comparison and analysis, the proposed combined forecasting model has the smallest statistical error and the best prediction accuracy; the MMED‐AT models based on the combined model can obviously eliminate the cumulative error of recursive multistep prediction and further improve the stability of multistep prediction.
Comparative assessment of pre‐ and inter‐stage hydrothermal treatment of municipal sludge for increased methane production
Authors: Zhang Chiqian , Liu Xiaoguang , Wang Qian , Tang Yuanzhi , Pavlostathis Spyros G.
Published: February 2021

Hydrothermal treatment (HT) is a promising technology to enhance anaerobic digestion (AD) of municipal sludge. However, the capacity of pre‐ and inter‐stage HT (i.e., HT‐AD and AD‐HT‐AD, respectively) to enhance the digestibility of municipal sludge has not been sufficiently explored. This study compared the efficacy of pre‐ and inter‐stage HT performed from 90 to 185°C to enhance methane production from a mixture of primary sludge and waste activated sludge using mesophilic (35°C) biochemical methane potential tests. In both configurations, sludge solubilization increased with HT temperature. HT‐AD, and to a greater extent AD‐HT‐AD, increased the release of ammonium nitrogen. Even though HT at 185°C dramatically increased sludge solubilization, the overall specific methane yield with HT at 185°C was lower than or comparable to that at lower HT temperatures in the HT‐AD and AD‐HT‐AD configurations, respectively. Up to 155°C HT, the overall specific methane yield with the HT‐AD configuration was higher by 4.9%–8.3% compared to the AD‐HT‐AD configuration. However, when the HT energy was considered, compared to the control (i.e., AD of sludge without HT), the net energy gain (ΔE) decreased as the HT temperature increased, becoming negative at an HT of 185°C. The AD‐HT‐AD configuration resulted in a higher overall volatile solids destruction (by 8.1 to 20.1%). In conclusion, for municipal sludge with a relatively high ultimate digestibility, as was the case in this study, HT‐AD is preferable as it has a smaller footprint and is easier to operate than the AD‐HT‐AD configuration. However, given the significantly higher volatile solids destruction in the AD‐HT‐AD configuration, compared to the HT‐AD configuration, AD‐HT‐AD may be more beneficial considering post‐AD sludge handling processes.

Practitioner points

Hydrothermal treatment (HT) increased the rate and extent of methane production from municipal sludge mixture.

155°C was the optimal temperature for either pre‐ or inter‐stage HT to increase biogas production.

Pre‐ and inter‐stage HT resulted in comparable ultimate methane production.

Pre‐stage HT is preferable to inter‐stage HT (smaller footprint, easier to operate).

AD‐HT‐AD resulted in significantly higher volatile solids destruction compared to the HT‐AD configuration.
Introduction to neural network‐based question answering over knowledge graphs
Authors: Chakraborty Nilesh , Lukovnikov Denis , Maheshwari Gaurav , Trivedi Priyansh , Lehmann Jens , Fischer Asja
Published: February 2021

Question answering has emerged as an intuitive way of querying structured data sources and has attracted significant advancements over the years. A large body of recent work on question answering over knowledge graphs (KGQA) employs neural network‐based systems. In this article, we provide an overview of these neural network‐based methods for KGQA. We introduce readers to the formalism and the challenges of the task, different paradigms and approaches, discuss notable advancements, and outline the emerging trends in the field. Through this article, we aim to provide newcomers to the field with a suitable entry point to semantic parsing for KGQA, and ease their process of making informed decisions while creating their own QA systems.

This article is categorized under:

Technologies > Machine Learning

Technologies > Prediction

Technologies > Artificial Intelligence
Erratum to: Generalizing the relativistic quantization condition to include all three-pion isospin channels
Authors: Hansen Maxwell T. , Romero-López Fernando , Sharpe Stephen R.
Published: February 2021

We have found an error in a statement following eq. (2.5) of our paper, concerning the function f (a, b, k) that first appears in that equation. The issue arises in the statement that it is convenient to take the function f (a, b, k) to be exchange symmetric with respect to its three arguments. This has the unwanted consequence of making six of the seven operators in the column vector of eq. (2.4) identically equal. This, in turn, implies that many operators are identically zero in the definite isospin basis, considered in section 2.4. To repair this, the last sentence of the paragraph containing eq. (2.4), starting “It is convenient for the subsequent…”, should be removed, as should footnote 3 and the next paragraph, beginning with “At this point, the reader may wonder why…”.
Sommerfeld-corrected relic abundance of wino dark matter with NLO electroweak potentials
Authors: Beneke Martin , Szafron Robert , Urban Kai
Published: February 2021

Abstract

Extending previous work, we calculate the electroweak potentials for all co-annihilation channels of wino dark matter at the one-loop order and obtain the wino relic abundance including the Sommerfeld effect at the next-to-leading order (NLO).