bluuebunny/crossref_metadata_2025 huggingface dataset:
Wildfire as a natural stressor and its effect on female phenotype and ornament development
Authors: Weiss Stacey L. , Brower Robert M.
Published: March 2021

Controlled low‐intensity fires are commonly used in ecosystem management for both habitat restoration and wildfire management. Animals in those ecosystems may respond to fire by shifting energy allocation away from reproduction and growth, and toward maintenance. Stress‐induced shifts in energy allocation may affect the expression of condition‐dependent sexual signals, which are sensitive to energetic and physiological trade‐offs mediated by glucocorticoids. Here, we examine the effect of fire on ornament expression, corticosterone, and other phenotypic traits in a population of striped plateau lizards, Sceloporus virgatus, affected by the Horseshoe 2 Fire in the Chiricahua Mountains, Arizona, USA. The condition‐dependent female ornament was significantly smaller the month following the fire than 2 years prior and was both smaller and less orange on the burned site relative to a nearby unburned site. These patterns are similar to those found in a previous experimental study examining the response of the ornament to corticosterone manipulations. Yet, in the current study, corticosterone levels were not different in lizards on the burned and unburned sites. Perhaps glucocorticoid levels already returned to baseline, or do not adequately track environmental change. Females tended to be smaller and lighter on the burned site than the unburned site; however, the year after the fire, body condition was higher for females on the burned site, indicating a rapid recovery and potential long‐term benefits in response to low‐intensity fires in this fire‐adapted ecosystem. We found that the lizards adjusted energy allocation away from sexual signaling and growth in response to low‐intensity fires. As fires and fire management are likely to increase in response to changing fire regimes across the globe, it will be important to consider behavioral and physiological responses of impacted species, as well as population‐, community‐, and ecosystem‐level responses.
Multiple‐trophic patterns of primary succession following retreat of a high‐elevation glacier
Authors: Hu Weiming , Schmidt Steven K. , Sommers Pacifica , Darcy John L. , Porazinska Dorota L.
Published: March 2021

How multiple, interacting components of complex soil communities assemble within forefields of receding glaciers is still largely unknown, especially at high‐elevation sites (>5000 m a.s.l.) where plant succession is very slow. To examine succession of soil communities across different trophic levels, we investigated four major soil groups: bacteria, fungi, nematodes, and other non‐fungal non‐nematode microbial eukaryotes at the Puca Glacier in the Peruvian Andes spanning 9‐, 24‐, and 89‐year‐old deglaciated soils. This is the first study of microbial communities, other than bacteria, at a high‐elevation chronosequence in the Andes Mountains. In addition, we characterized soil biogeochemical properties (e.g., C, N, moisture, and pH) and rates of microbial enzyme activities associated with C, N, and P acquisition. We found significantly correlated increases in estimated richness and high species turnover in all soil groups along the chronosequence. These shifts in soil communities were significantly correlated with microbial enzyme activities and measures of C, N, moisture, and pH. Stoichiometric comparisons of enzyme activities showed phosphorus (P) and carbon (C) limitation of microbial activity across the entire chronosequence with no hint of nitrogen (N) limitation. Taken together, the observed shifts in soil communities and biogeochemistry indicate coordinated increases in trophic complexity and ecosystem functioning during the initial 90 yr of microbial succession along the post‐glacial chronosequence of the Puca Glacier.
True blue: Temporal and spatial stability of pelagic wildlife at a submarine canyon
Authors: Forrest J. A. H. , Bouchet P. J. , Barley S. C. , McLennan A. G. , Meeuwig J. J.
Published: March 2021

In coastal systems, marine‐protected areas (MPAs) have been shown to increase the diversity, abundance, and biomass of wildlife assemblages as well as their resilience to climate change. The effectiveness of pelagic MPAs is less clear, with arguments against their establishment typically based on the highly mobile nature of pelagic taxa. We used mid‐water stereo‐baited remote underwater video systems (stereo‐BRUVS) and spatial predictive models to characterize the pelagic wildlife assemblage at the head of the Perth Canyon, one of the largest submarine canyons in Australia, over a 7‐yr period (2013–2019). The total number of unique taxa and mean values of taxonomic richness, abundance, fork length, and biomass demonstrated strong interannual stability, although mean taxonomic richness and abundance were significantly lower in 2018 relative to other years. Seasonal variability was absent in 2016, but in 2018, taxonomic richness and abundance were three times greater in the Austral spring than in the autumn. Some mobile megafauna were only recorded at the Perth Canyon Marine Park (PCMP) in the autumn, suggesting a seasonal component to their occurrence. The fine‐scale distribution of pelagic taxa at the canyon head was largely stable over time, with many areas of higher relative probability of presence located outside protected zones. Despite a degree of variability that may relate to the effect of the El Niño Southern Oscillation on the Leeuwin Current, the PCMP assemblage demonstrates a relatively high degree of spatiotemporal stability. Stronger protection of the PCMP (IUCN II or higher) would potentially improve conservation outcomes for many species of pelagic wildlife.
Measuring savanna woody cover at scale to inform ecosystem restoration
Authors: Loewensteiner David A. , Bartolo Renee E. , Whiteside Timothy G. , Esparon Andrew J. , Humphrey Chris L.
Published: March 2021

The maturity of remote sensing and ecosystem restoration science provides new opportunities to monitor and assess ecosystem indicators at finer resolutions and at suitable scales. A key link in joining these fields is creating a framework to apply these rich datasets to ecosystem restoration projects. Savanna woodland ecosystems have discontinuous tree cover that is an important, but potentially highly variable, structural component of these ecosystems. Woody cover in savannas is also well suited to being measured with remote sensing techniques. We extracted woody cover from a 66‐yr time series of aerial imagery covering 1718 ha of mesic savanna ecosystem in northern Australia, adjacent to the Ranger uranium mine and encompassing portions of Kakadu National Park. This ecosystem is proposed as a reference ecosystem that may be used to comparatively assess and monitor restoration trajectories of the mine site in the coming decades. The spatiotemporal patterns of change in woody cover were assessed at spatial extents similar to the mine site. We were able to construct a robust distribution of canopy cover values and associated spatial heterogeneity that can be used to set closure criteria, inform restoration trajectories, and guide monitoring activities for the restored mine site.
Geophysical templates modulate the structure of stream food webs dominated by omnivory
Authors: Zatkos Lauren , Arismendi Ivan , Johnson Sherri L. , Penaluna Brooke E.
Published: March 2021

Food webs show the architecture of trophic relationships, revealing the biodiversity and species interactions in an ecosystem. Understanding which factors modulate the structure of food webs offers us the ability to predict how they will change when influential factors are altered. To date, most of the research about food webs has focused on species interactions whereas the influences of surrounding environments have been overlooked. Here, using network analysis, we identified how the structure of aquatic food webs varied across a range of geophysical conditions within a whole stream system. Within a headwater basin in the Cascade Mountain Range, Oregon, USA, macroinvertebrate and vertebrate composition was investigated at 18 sites. Predator–prey interactions were compiled based on existing literature and dietary analysis. Several structural network metrics were calculated for each food web. We show that the structure of food webs was predictable based on geophysical features at both local (i.e., slope) and broader (i.e., basin size) spatial extents. Increased omnivory, greater connectance, shorter path lengths, and ultimately greater complexity and resilience existed downstream compared to upstream in the stream network. Surprisingly, the variation in food web structure was not associated with geographic proximity. Structural metric values and abundance of omnivory suggest high levels of stability for these food webs. There is a predictable variation in the structure of food webs across the network that is influenced by both longitudinal position within streams and patchy discontinuities in habitat. Hence, findings illustrate that the slightly differing perspectives from the River Continuum Concept, Discontinuity Patch Dynamics, and Process Domains can be integrated and unified using food web networks. Our analyses extend ecologists’ understanding of the stability of food webs and are a vital step toward predicting how webs and communities may respond to both natural disturbances and current global environmental change.
Dinuclear Nickel(II) and Copper(II) Complexes of 8‐Quinoline‐1H‐pyrazole‐3‐carboxamide: Crystal Structure, Magnetic Properties, and DFT Calculations
Authors: Mohammadnezhad Gholamhossein , Ahfad Neda , Meghdadi Soraya , Farrokhpour Hossein , Schmitz Simon , Haseloer Alexander , Buchholz Axel , Plass Winfried , Klein Axel
Published: March 2021

Homoleptic dinuclear complexes [M2(qpyzc)2] (M=Cu (1) or Ni (2) were obtained from the readily synthesised trischelate pyrazole‐based qpyzc ligand (H2qpyzc=8‐quinoline‐1H‐pyrazole‐3‐carboxamide). Their crystal and molecular structures, magnetic properties, and UV‐vis spectra were reported alongside with DFT and TD‐DFT calculations. Trigonality index τ’4 values of 0.25 and 0.21 for the Cu and Ni centres, respectively reveal a marked distortion from square planar geometry. The two metal coordination planes within a complex are tilted towards each other with 40.2(1)° for Cu(II) and 34.5(2)° for Ni(II). The central six‐membered M2N4 metallocycle is almost planar and the two anionic pyrazolate rings are tilted towards each other by 37.4(1)° (1) and 38.5(2)° (2), respectively. Regardless of this peculiar bonding situation magnetic measurements on 1 are in line with medium‐sized antiferromagnetic coupling with a coupling constant of J=−100 cm−1, an isotropic g value of 2.11 and an S=0 ground state. Complex 2 seems to be diamagnetic. DFT calculations gave an excellent agreement between calculated and experimental metrics of the complexes and supported the prevalence of the singlet ground state for 1. TD‐DFT calculated UV‐vis absorption spectra agree well with observed absorptions and the red colour of both compounds.
Making Sense of Life-History Effects of the Antidepressant Citalopram in the Copepod Nitocra spinipes Using a Bioenergetics Model
Authors: Koch Josef , De Schamphelaere Karel A.C.
Published: March 2021

The global consumption of human antidepressants has steadily increased over the last years. The most widely prescribed antidepressants are the selective serotonin reuptake inhibitors (SSRIs), which have been linked to various life-history effects in nontarget organisms. We investigated the effects of the SSRI citalopram hydrobromide on the life history of the copepod Nitocra spinipes. Slight but significant developmental delay effects were observed at nominal concentrations of 0.1 and 1 µg/L, with stronger effects occurring at measured concentrations of 178 µg/L and above. At 77 µg/L and above, a significant increase in adult body length and offspring production/brood was found, although the time between brood releases remained unaffected. The pre-adult surviving fraction was significantly reduced (by 44%) at 765 µg/L. For a mechanistic evaluation of these observations, we used a bioenergetics model for N. spinipes based on the dynamic energy budget theory. Toxicokinetic and toxicodynamic submodels were used to dynamically simulate the chemical uptake and elimination, as well as dose–response relationships for hypothetical physiological modes of action and survival over time. Although none of the commonly invoked physiological modes of action, acting on assimilation, maintenance, growth, or offspring production, could explain the observed combination of effects, a newly proposed physiological mode of action acting on the process of maturation delivered correct predictions in terms of each effect's direction. The model fits could be further improved by allowing for a gentler concentration–effect slope and by adding an auxiliary physiological mode of action acting on the reproduction efficiency. The quantitative explanations provided in the present study offer a starting point for exploratory simulation studies investigating the effects of SSRIs at higher ecological levels. Environ Toxicol Chem 2021;40:1926–1937. © 2021 SETAC
Compositional profile of barley landlines grown in different regions of Gilgit‐Baltistan
Authors: Hussain Abid , Ali Sartaj , Hussain Azhar , Hussain Zubair , Manzoor Muhammad Faisal , Hussain Abid , Ali Amjad , Mahmood Talat , Abbasi Kashif Sarfraz , Karrar Emad , Hussain Maqsood ,   Tajudin
Published: March 2021

The current investigation was performed to explore the nutritional and functional composition of four landlines of barley denoted as LB1 (Gilgit), LB2 (Nagar), LB3 (Skardu), and LB4 (Shigar) from different regions of Gilgit‐Baltistan. The samples were examined for nutritional profile and antioxidant attributes. Total phenolic values and total flavonoid results were in the range of 1.2 to 3.1 mg/g and 0.41 to 0.55 mg/g, respectively. Nutritional profile as crude starch, fiber, protein, ash, and fat ranged from 56.3%–50.80%, 16.50%–11.73%, 16.20%–11.53%, 2.8%–2.1%, and 2.63%–1.63%, respectively. The mineral composition in terms of Mg (527–616 mg/kg) was higher in the landlines followed by Ca (312–368 mg/kg), Na (122.6–146.6 mg/kg), Fe (43.3–65.6 mg/kg), and Zn (22.5–26.6 mg/kg). It was concluded that the indigenous barley landlines had immense nutritional potential and functional attributes. Thus, it can be used for value‐added food products and the development of cottage industry in the region.
Cryptocurrency price prediction using traditional statistical and machine‐learning techniques: A survey
Authors: Khedr Ahmed M. , Arif Ifra , P V Pravija Raj , El‐Bannany Magdi , Alhashmi Saadat M. , Sreedharan Meenu
Published: March 2021

Cryptocurrencies are decentralized electronic counterparts of government‐issued money. The first and best‐known cryptocurrency example is bitcoin. Cryptocurrencies are used to make transactions anonymously and securely over the internet. The decentralization behavior of a cryptocurrency has radically reduced central control over them, thereby influencing international trade and relations. Wide fluctuations in cryptocurrency prices motivate the urgent requirement for an accurate model to predict its price. Cryptocurrency price prediction is one of the trending areas among researchers. Research work in this field uses traditional statistical and machine‐learning techniques, such as Bayesian regression, logistic regression, linear regression, support vector machine, artificial neural network, deep learning, and reinforcement learning. No seasonal effects exist in cryptocurrency, making it hard to predict using a statistical approach. Traditional statistical methods, although simple to implement and interpret, require a lot of statistical assumptions that could be unrealistic, leaving machine learning as the best technology in this field, being capable of predicting price based on experience. This article provides a comprehensive summary of the previous studies in the field of cryptocurrency price prediction from 2010 to 2020. The discussion presented in this article will help researchers to fill the gap in existing studies and gain more future insight.
Betulin ameliorates 7,12‐dimethylbenz(a)anthracene‐induced rat mammary cancer by modulating MAPK and AhR/Nrf‐2 signaling pathway
Authors: Zhang Jinku , Zhou Bingjuan , Sun Jirui , Chen Hong , Yang Zhao
Published: March 2021

The aim of the present study is to explore the preventive efficacy of betulin (BE) in 7,12‐dimethylbenz(a)anthracene (DMBA)‐administered mammary cancer by modulating Ahr/Nrf2 signaling in experimental models. The mammary cancer was stimulated by the addition of DMBA (25 mg/kg/b.Wt) mixed in 1 ml of vehicle solution (sunflower oil and saline 1:1) through subcutaneous injection. The DMBA‐exposed mammary tumor models showed low bodyweight, elevated quantities of lipid peroxidation molecules (TBARS and LOOH), and low enzymatic (GPx, SOD, and CAT), and nonenzymatic (GSH, vitamin C, and vitamin E) antioxidant activities in plasma and mammary tissues. Moreover, histopathological studies confirmed that invasive ductal carcinoma was observed in DMBA‐induced mammary tissue of the experimental model. Dietary oral supplementation of BE prevents the loss of bodyweight, overproduces lipid peroxidation, and restores the antioxidant activities in DMBA‐exposed experimental animals. The nuclear factor erythroid 2‐related factor 2 (Nrf2) is a crucial antioxidant protein that involves preventing numerous cancers. Therefore, Nrf2‐associated signaling concern is a significant target for preventing mammary cancer. This study observed an increased expression of MAPKs, Keap1, ARNT, AhR, and CYP1A1, whereas decreased expression of HO‐1 and Nrf2 in DMBA‐induced cancer‐bearing experimental animals. The oral supplementation of BE effectively modulates the expression of MAPKs, AhR/Nrf2‐associated protein expressions in DMBA‐exposed experimental animals. This current study concluded that BE is a strong antioxidant, which triggers the MAPKs‐mediated oxidative stress and inhibits proliferative markers by restoring the activity of Nrf2 signaling.
Non long‐range corrected density functionals incorrectly describe the intensity of the CH stretching band in polycyclic aromatic hydrocarbons
Authors: Geindre Hugo , Allouche Abdul‐Rahman , Peláez Daniel
Published: March 2021

We present a comprehensive study of the most relevant numerical aspects influencing frequencies and intensities in the infrared spectrum of isolated polycyclic aromatic hydrocarbons (PAHs) regarding the overestimate of the IR CH‐stretching bands. We use naphthalene as benchmark and show the validity of our results to different members of the PAH family. Our analysis relies on widely employed density functional theory methods and second‐order vibrational perturbational theory for the computation of vibrational eigenstates. We have focused on the elucidation of the origin of the systematic overestimate of the intensities in the CH‐stretching region. To rule out nonfundamental numerical errors, we have initially considered the influence of the electronic basis set and various other parameters on the different stages of the vibrational analysis. In a second stage, we have benchmarked the results of different density functional theory functionals with respect to the aforementioned overestimate taken as the ratio between the most prominent features of the spectrum, the CH‐bending and the CH‐stretching bands. Our results unambiguously indicate that the long‐range correction plays a major role in this spurious numerical issue. More specifically, this phenomenon is due to an incorrect description of the charge distribution (and hence dipole) within the symmetrically relevant CH bonds. Long‐range correction specifically remedies this issue. It improves the description of the intensities in the stretching region while at the same time it does not perturb significantly the rest of the spectrum. With respect to the frequencies, we have observed an overall improvement when compared to noncorrected functionals.
Doubling the optical efficiency of color‐converted micro‐light‐emitting diode displays with a patterned cholesteric liquid crystal polymer film
Authors: Hsiang En‐Lin , Li Yannanqi , He Ziqian , Zhan Tao , Zhang Caicai , Lan Yi‐Fen , Dong Yajie , Wu Shin‐Tson
Published: March 2021

We propose a patterned cholesteric liquid crystal (CLC) polymer film as a self‐assembled Bragg reflector to enhance the performance of a color‐converted micro‐light‐emitting diode (LED) display system. In the display system, we firstly optimize the device structure of blue LED chip to maintain a high light extraction efficiency and low optical crosstalk. Next, we fabricate several patterned CLC films with feature sizes ranging from 10 to 80 μm. By integrating the patterned CLC film into a color‐conversion micro‐LED display, the optical efficiency is doubled while keeping a color gamut of about 90% Rec. 2020. Finally, we carry out a proof‐of‐concept experiment to validate the functionality of such a patterned CLC film.
Development and validation of a gas chromatography method coupled with flame ionization detector for quantitative analysis of fragrance allergens in aromas for e‐cigarettes
Authors: Pawelec Aleksandra , Wielgomas Bartosz
Published: March 2021

Aromas can give smell and/or flavor to a variety of products in the cosmetic and food industry. They are also used as e‐cigarette additives. Some of those substances are recognized as fragrance allergens and can cause allergic reactions so there is a need to control their use. Gas chromatography is the method of choice for analyzing fragrance allergens because of their low boiling points. This study aimed to develop and validate a robust and simple method for the analysis of fragrance allergens in aromas for e‐cigarettes. A method using gas chromatography coupled with a flame ionization detector was developed for 25 fragrance allergens. Optimized parameters were sample diluent, internal standard, and carrier gas. The output method was the one previously developed and optimized. The linearity of the method was >0.994 over the range of 0.5–40 μg/mL. Accuracy and precision were within the acceptance range. Limits of detection and quantification were determined, and calibration curves were plotted. The method was applied to three real samples of aromas. Thirteen fragrance allergens were detected. Concentrations varied in the range of dozens to thousands of μg/mL showed that concentrations of fragrances in aromas for e‐cigarettes can be high and varies among products.
4‐Phenylbutyric acid, a potent endoplasmic reticulum stress inhibitor, attenuates the severity of collagen‐induced arthritis in mice via inhibition of proliferation and inflammatory responses of synovial fibroblasts
Authors: Choi Yunjung , Lee Eun‐Gyeong , Jeong Ji‐Hyeon , Yoo Wan‐Hee
Published: March 2021

4‐Phenylbutyric acid (4‐PBA) exerts potent pharmacological effects, including anti‐inflammatory properties, via inhibition of endoplasmic reticulum (ER) stress. However, it is not known whether 4‐PBA attenuates the severity of rheumatoid arthritis. The present study aimed to determine whether the inhibition of ER stress by 4‐PBA ameliorated experimentally induced arthritis. The proliferation of synovial fibroblasts (SFs) and expression of matrix metalloproteinases (MMPs) were evaluated in the presence of interleukin (IL)‐1β with or without 4‐PBA. The effect of 4‐PBA on the phosphorylation of Mitogen‐activated protein kinase (MAPK) and the activation of Nuclear factor‐κB (NF‐κB) in IL‐1β‐stimulated SFs was assessed. In an in vivo study, the effects of 4‐PBA were investigated using DBA/1 mice with collagen‐induced arthritis (CIA). Clinical, histological, and serological assessments of CIA treated with 4‐PBA were performed to determine the therapeutic effect of 4‐PBA. In vitro, 4‐PBA inhibited the proliferation and expression of IL‐1β‐stimulated SFs and MMP‐1 and MMP‐3 through the suppression of both the phosphorylation of MAPKs and NF‐κB in IL‐1β‐stimulated SFs. The 4‐PBA treatment markedly attenuated the severity of arthritis in CIA mice. The 4‐PBA treatment ameliorated joint swelling and the degree of bone erosion and destruction and decreased the level of inflammatory cytokines and MMP‐3 and Cox‐2. Furthermore, remarkable improvements in histopathological findings occurred in 4‐PBA‐treated mice. These findings suggested that 4‐PBA could attenuate the severity of arthritis in CIA mice by partially blocking the phosphorylation of MAPKs and the activation of NF‐κB in SFs. Thus, through the inhibition of ER stress, 4‐PBA may be a potent agent for the treatment of RA.
Dynamic Heterogeneity of Filler‐Associated Interphases in Polymer Nanocomposites
Authors: Schneider Horst , Roos Matthias , Golitsyn Yury , Steiner Kerstin , Saalwächter Kay
Published: March 2021

Dynamically inhomogeneous polymer systems exhibit interphases with mobility gradients. These are believed to play key roles in the material's performance. A prominent example is particle‐filled rubber, a special case of a crosslinked polymer nanocomposite, where favorable rubber‐filler interactions may give rise to a nanoscale immobilized layer around the filler, including regions of intermediate mobility. Such intermediate domains may either form a separate shell‐like layer or be a manifestation of dynamic heterogeneities, in which case the intermediately mobile material would be dispersed in the form of nanometer‐sized subdomains. In this contribution, bidirectional proton NMR spin diffusion (SD) experiments applied to silica‐filled acrylate rubber are combined with numerical simulations to provide microscopic insights into this question. While model calculations for different scenarios fit the given data similarly well for longer SD mixing time, the short‐time data do support the presence of dynamic heterogeneities.
Optimal control model of immunotherapy for autoimmune diseases
Authors: Costa M. Fernanda P. , Ramos M.P. , Ribeiro C. , Soares A.J.
Published: March 2021

In this work, we develop a new mathematical model to evaluate the impact of drug therapies on autoimmunity disease. We describe the immune system interactions at the cellular level, using the kinetic theory approach, by considering self‐antigen presenting cells, self‐reactive T cells, immunosuppressive cells, and Interleukin‐2 (IL‐2) cytokines. The drug therapy consists of an intake of Interleukin‐2 cytokines which boosts the effect of immunosuppressive cells on the autoimmune reaction. We also derive the macroscopic model relative to the kinetic system and study the wellposedness of the Cauchy problem for the corresponding system of equations. We formulate an optimal control problem relative to the model so that the quantity of both the self‐reactive T cells that are produced in the body and the Interleukin‐2 cytokines that are administrated is simultaneously minimized. Moreover, we perform some numerical tests in view of investigating optimal treatment strategies and the results reveal that the optimal control approach provides good‐quality approximate solutions and shows to be a valuable procedure in identifying optimal treatment strategies.
Impact of multimodal strategies to reduce multidrug‐resistant organisms in surgical intensive care units: Knowledge, practices and transmission: A quasi‐experimental study
Authors: Kasatpibal Nongyao , Chittawatanarat Kaweesak , Nunngam Nantana , Kampeerapanya Daranee , Duangsoy Nongnut , Rachakom Chanban , Soison Ubonrat , Apisarnthanarak Anucha
Published: March 2021

Aim

This study examined the effects of multimodal strategies on knowledge and practices in preventing multidrug‐resistant organism (MDRO) transmission among healthcare personnel (HCP), and to investigate MDRO transmission in two surgical intensive care units (SICUs).

Design

A quasi‐experimental study with a one‐group pretest–posttest design.

Methods

We recruited 62 HCP. Data were collected during 2017–2019. Multimodal strategies, including training, educational and reminder posters, an educational YouTube channel, champions and feedback, were used to enhance knowledge and practices. Data were analysed using Wilcoxon signed‐rank test and chi‐square test.

Results

After the intervention, median knowledge scores increased from 16.0 to 17.0 (p = .001), and overall correct MDRO prevention practices increased from 76.6% to 94.0% (p < .001). The MDRO transmission rate decreased from 25% to 0% (p < .001).

Conclusion

The findings indicate that multimodal strategies could enhance knowledge and practices for preventing MDRO transmission among HCP and could reduce the MDRO transmission rate in SICUs.
Describing the Weight‐Reduced State: Physiology, Behavior, and Interventions
Authors: Aronne Louis J. , Hall Kevin D. , M. Jakicic John , Leibel Rudolph L. , Lowe Michael R. , Rosenbaum Michael , Klein Samuel
Published: March 2021

Although many persons with obesity can lose weight by lifestyle (diet and physical activity) therapy, successful long‐term weight loss is difficult to achieve, and most people who lose weight regain their lost weight over time. The neurohormonal, physiological, and behavioral factors that promote weight recidivism are unclear and complex. The National Institute of Diabetes and Digestive and Kidney Diseases convened a workshop in June 2019, titled “The Physiology of the Weight‐Reduced State,” to explore the mechanisms and integrative physiology of adaptations in appetite, energy expenditure, and thermogenesis that occur in the weight‐reduced state and that may oppose weight‐loss maintenance. The proceedings from the first session of this workshop are presented here. Drs. Michael Rosenbaum, Kevin Hall, and Rudolph Leibel discussed the physiological factors that contribute to weight regain; Dr. Michael Lowe discussed the biobehavioral issues involved in weight‐loss maintenance; Dr. John Jakicic discussed the influence of physical activity on long‐term weight‐loss maintenance; and Dr. Louis Aronne discussed the ability of drug therapy to maintain weight loss.
The Gut/Lung Microbiome Axis in Obesity, Asthma, and Bariatric Surgery: A Literature Review
Authors: Kim Yeon Ji , Womble Jack T. , Gunsch Claudia K. , Ingram Jennifer L.
Published: March 2021

Mounting evidence suggests that obesity, parameters of metabolic syndrome, and asthma are significantly associated. Interestingly, these conditions are also associated with microbiome dysbiosis, notably in the airway microbiome for patients with asthma and in the gut microbiome for patients with obesity and/or metabolic syndrome. Considering that improvements in asthma control, lung function, and airway hyperresponsiveness are often reported after bariatric surgery, this review investigated the potential role of bacterial gut and airway microbiome changes after bariatric surgery in ameliorating asthma symptoms. Rapid and persistent gut microbiota alterations were reported following surgery, some of which can be sustained for years. The gut microbiome is thought to modulate airway cellular responses via short‐chain fatty acids and inflammatory mediators, such that increased propionate and butyrate levels following surgery may aid in reducing asthma symptoms. In addition, increased prevalence of Akkermansia muciniphila after Roux‐en‐Y gastric bypass and sleeve gastrectomy may confer protection against airway hyperreactivity and inflammation. Metabolic syndrome parameters also improved following bariatric surgery, and whether weight‐loss‐independent metabolic changes affect airway processes and asthma pathobiology merits further research. Fulfilling knowledge gaps outlined in this review could facilitate the development of new therapeutic options for patients with obesity and asthma.
Development of biaxial stretchable nonwoven paddings using novel polymeric fibers
Authors: Arumugam Veerakumar , Yang Guang , Wu Yingsi , Yong Hui Ting , Tok Alfred Iing Yoong , Lipik Vitali
Published: March 2021

Nonwoven paddings with superior stretch and recovery properties in both directions with good thermal insulation properties were developed for application in winter clothes. Paddings were developed using a self‐crimping elastic fiber composed of both polyethylene terephthalate (PET) and polytrimethylene terephthalate (PTT) polymers, polyester fiber balls, polypropylene fiber balls, along with bicomponent as binder fibers at different blending ratios through carding, postthermal bonding, and gluing process. Developed paddings were characterized and analyzed for their biaxial stretch and recovery behavior, elongation under tensile load, stiffness, thermal insulation, and washing stability. In addition, energy loss was calculated and reported from hysteresis curve obtained during 40% loading (stretch) and unloading (recovery) cycle. The results were statistically evaluated to determine whether fiber types and blend ratios have significant effect on nonwoven paddings properties. This study indicates that nonwoven padding composed of naturally crimped elastic fibers: binder fibers (50:50) has ability to stretch around 120‐140% in both directions, 95% total recovery with minimal energy loss upon 40% stretch and recovery cycle, and it has sustainable tensile breaking load around 11 N along cross direction and 20 N along machine direction. It has stiffness load 5 N which is flexible enough for required applications, possesses good thermal insulation properties, and holds their structural properties after five washing cycles. From statistical analysis, ANOVA results exhibited that the used fiber types and their weight percentages significantly affect stretch and recovery, other properties of nonwoven paddings for required application.
In situ construction of fiber‐supported micro‐porous char structure to enhance anti‐ablative performance of silicone rubber composites
Authors: Huang Yisen , Kong Yiran , Yan Liwei , Zou Huawei , Chen Yang , Liang Mei
Published: March 2021

Ablation‐resistant polymeric composites play a crucial role in the thermal protection system for the entire aerospace industry. Constructing a stable char layer especially with low thermal conductivity is essential to enhance the ablation resistant properties of polymer‐based ablatives. In this article, basic magnesium carbonate (MgCO3) and carbon fibers (CFs) were introduced to silicone rubber with an aim of building fiber‐supported micro‐porous char structure in situ, thereby improving ablation resistance properties. Thermogravimetric analyses revealed that the addition of MgCO3significantly increased the char residue of the composites. Oxyacetylene torch tests indicated that the addition of MgCO3/CFs greatly improved the thermal insulation of the composites, and the linear ablation rates of the composites were reduced by 30.76% compared to the virgin silicone rubber. Shore A hardness and thermal conductivity tests revealed that composites with 10 phr MgCO3exhibited a char structure with proper strength and low thermal conductivity. SiC, Mg2SiO4, and MgSiO3were produced in the MgCO3/CFs‐modified composites, as characterized by X‐ray diffraction. Combined with macro lens and scanning electron misroscopy, it was proven that a fiber‐supported micro‐porous and thermally insulated char structure was conducive to the improvement of the ablation properties, which can be applied to aerospace systems for thermal shielding applications.
Tuning morphology of siloxane bond‐based polybenzoxazines by controlling the sol–gel and curing processes
Authors: Forchetti Casarino Agustin , Bortolato Santiago Andrés , Estenoz Diana Alejandra , Spontón Marisa Elisabet
Published: March 2021

Novel polybenzoxazine/polysilsesquioxane nanocomposites were synthesized with uniform and reproducible structural morphology, high Tg, and good thermal stability. Polysilsesquioxane was oriented in a nanometer‐size lamellar structure. Benzoxazine monomer based on silane (BA‐3aptms) was synthesized by reaction between bisphenol A, 3‐(trimethoxysilyl)propylamine, and paraformaldehyde in a 1:2:4 molar ratio. Four experimental conditions of the two stage sol–gel process for polysilsesquioxane were studied, and their effect on the material characteristics investigated. In the first stage, hydrolysis was favored, while the second stage mostly consisted of condensation. The reaction condition with the longest hydrolysis time allowed the increase of the concentration of silanol units and the selective condensation, favoring the formation of a higher amount of cage‐like cyclic structures. In addition, this experimental procedure was well controlled so that the sol–gel and oxazine‐ring opening reactions were extremely reproducible from batch to batch. All processes were monitored by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis and dynamic mechanical thermal analysis, scanning electron and transmission electron microscopies, and X‐ray diffraction. A chemometric approach based on a multivariate curve resolution model was applied to the FTIR spectra, which allowed the identification of four reaction components associated with the sol–gel and the curing processes.
Conservative management of congenital bronchial atresia: The Bambino Gesù children's hospital experience
Authors: Zarfati Angelo , Voglino Valerio , Tomà Paolo , Cutrera Renato , Frediani Simone , Inserra Alessandro
Published: March 2021

Introduction

Congenital bronchial atresia (CBA) is a rare airway malformation. No management guidelines exist because of limited evidence: treatment, surgical or conservative, is based on consensus and opinion. Objective: To review the experience of a pediatric tertiary center and provide additional data about nonsurgical management of CBA and its outcomes after a structured follow‐up, and to help formulate appropriate evidence‐based guidelines.

Methods

A retrospective analysis of clinical, radiological, surgical, and pathological data of all pediatric patients with suspicion of CBA referred to the surgical department of the Bambino Gesù children's hospital of Rome between December 2013 and 2019, along with a review of the literature.

Results

Among the 18 children initially included in the study, 2 were lost to follow‐up after radiological diagnosis, 4 underwent surgery for radiological suspicion of other pulmonary malformations. The final population is composed of 12 conservatively managed patients. At the end of the follow‐up (median: 29 months, range 3–61), 1 patient (8%) was symptomatic.

Conclusion

Conservative management for CBA appears to be safe. Surgery should be reserved for patients with symptomatic or complicated cases.
Improving integrative 3D modeling into low‐ to medium‐resolution electron microscopy structures with evolutionary couplings
Authors: McCafferty Caitlyn L. , Taylor David W. , Marcotte Edward M.
Published: March 2021

Electron microscopy (EM) continues to provide near‐atomic resolution structures for well‐behaved proteins and protein complexes. Unfortunately, structures of some complexes are limited to low‐ to medium‐resolution due to biochemical or conformational heterogeneity. Thus, the application of unbiased systematic methods for fitting individual structures into EM maps is important. A method that employs co‐evolutionary information obtained solely from sequence data could prove invaluable for quick, confident localization of subunits within these structures. Here, we incorporate the co‐evolution of intermolecular amino acids as a new type of distance restraint in the integrative modeling platform in order to build three‐dimensional models of atomic structures into EM maps ranging from 10–14 Å in resolution. We validate this method using four complexes of known structure, where we highlight the conservation of intermolecular couplings despite dynamic conformational changes using the BAM complex. Finally, we use this method to assemble the subunits of the bacterial holo‐translocon into a model that agrees with previous biochemical data. The use of evolutionary couplings in integrative modeling improves systematic, unbiased fitting of atomic models into medium‐ to low‐resolution EM maps, providing additional information to integrative models lacking in spatial data.
Gallium Nitride Doping with Carbon: A Thermodynamic Analysis
Authors: Karpov Sergey Yu.
Published: March 2021

A thermodynamic model of GaN doping with carbon accompanied by native defect formation is developed, based on ab initio calculations as input data. A correction procedure for defect formation energies is suggested to account for realistic growth conditions and thermodynamic reservoir, providing atomic exchange involved in impurity incorporation and defect generation. Applied to undoped and Si‐doped GaN grown by metal‐organic vapor phase epitaxy (MOVPE), the model demonstrates the amphoteric nature of carbon, leading to simultaneous formation of donor and acceptor states. The role of nitrogen vacancies controlling background electron conductivity in undoped GaN and the carbon distribution between cation and anion sites as a function of growth conditions are also discussed in terms of the model. The relationship between the total carbon concentration in GaN and the density of traps capable of capturing electrons is analyzed, which is important for GaN:C application as a high‐resistance buffer material for electronic devices.
Effect of Light and Heat on Polymer‐Based Resistive Random Access Memory
Authors: Mahato Bipul Kumar , Medwal Rohit , Deen Ghulam Roshan , Piramanayagam S. N. , Rawat Rajdeep Singh
Published: March 2021

Highly repeatable, photosensitive nonvolatile resistive random access memory (ReRAM) made of a Si/SiO2/Cu/PRPC/Ta stack with a photoresponsive polymer composite (PRPC) as the active medium is presented. The device shows errorless bipolar resistive switching with more than 100 cycles repeatability and stable SET and RESET voltages. It changes its resistive states in response to white light and recovers completely after removal of the light source. It also changes its state in response to heat and recovers randomly after the removal of the heat source. The phenomenon is explained by valance charge transfer along with a space‐charge‐limited conduction (SCLC) mechanism. The initial state of the device is low resistance state (LRS) because of electric‐field‐induced formation of valance charge transfer states. It switches to a high resistance state (HRS) due to electric‐field‐induced dissociation of the charge transfer states.
Effective collisional cross‐section of small ions in the gas phase: Application to ion mobility spectrometry
Authors: Parchami Razieh , Tabrizchi Mahmoud
Published: March 2021

Rationale

The observed drift times of monoatomic ions, including alkali metal ions and halide anions, are not fully consistent with their size. When the effect of mass is included through the Mason–Schamp equation, the deviation gets worse so that the trend of the experimental collisional cross‐sections becomes completely opposite to what is expected. This is attributed to the stronger local electric field around smaller ions. The strong electric field in the vicinity of a small ion leads to strong ion–neutral interactions and creates a drag force against ion motion. The smaller the ions, the stronger the interaction, because of the higher charge density.

Methods

In view of this, a modified equation is introduced to describe the relationship between the observed drift times or ion mobilities and the cross‐sections of small ions. Here, for small ions with high charge density, the experimental collision cross‐section is expressed as the effective collision cross‐section, Ωeff = σi(1 + α/ri3), that takes into account both intrinsic ion size, σi, and the ion–molecule interactions through a correction term of α/ri3, which is proportional to the charge density.

Results

A linear fit of the drift times of alkali metal ions and halide anions to the proposed equation showed relative deviations of <8.2%. The model successfully predicted the drift time of other small diatomic ions with reasonable error.

Conclusions

The proposed model can be used as a simple and efficient relationship in predicting the effective cross‐section of small ions.
Event‐triggered and self‐triggered gain scheduling control of input constrained systems with applications to the spacecraft rendezvous
Authors: Zhang Kai , Zhou Bin , Jiang Huaiyuan , Duan Guangren
Published: March 2021

This article studies event‐triggered and self‐triggered gain scheduling control design for semi‐global stabilization of input constrained linear systems. Using the parametric Lyapunov equation (PLE), a event‐triggered gain scheduling control, which can increase the convergence rate of the closed‐loop systems by designing a gain scheduling scheme and save the communication resources by building an event generator, is designed. In order to avoid continuously monitoring the system states, the self‐triggered gain scheduling control algorithms are also designed. The non‐occurrence of the Zeno phenomenon and the boundedness of the parameter in the PLE are proved. The impact of the parameter on the minimal inter‐event time is analyzed, which allows us to find easily a trade‐off between the inter‐event times and the control performance. Another advantage of the designed methods is that the controller is linear. Finally, the proposed control algorithms are applied to stabilize the spacecraft rendezvous control system and the numerical simulation result shows the efficacy of the control algorithms.
Laser‐Guided Corrosion Control: A New Approach to Tailor the Degradation of Mg‐Alloys
Authors: Pou‐Álvarez Pablo , Riveiro Antonio , Nóvoa Xosé Ramón , Jin Xueze , del Val Jesús , Comesaña Rafael , Boutinguiza Mohamed , Lusquiños Fernando , Jones Julian R. , Pérez‐Prado María Teresa , Pou Juan
Published: March 2021

Despite corrosion being commonly seen as a problem to be avoided, applications such as batteries or biodegradable implants do benefit from corrosion‐like phenomena. However, current strategies address corrosion control from a global perspective for a whole component, without considering local adaptations to functionality specifications or inhomogeneous environments. Here, a novel concept is presented: the local control and guidance of corrosion through a laser surface treatment. Immersion tests in saline solution of AZ31 magnesium alloy samples show degradation rates reduced up to 15 times with the treatment, owing to a fast passivation after the induced microstructural modifications. By controlling the treatment conditions, the degradation can be restricted to delimited regions and driven towards specific directions. The applicability of the method for the design of tailored degradation biomedical implants is demonstrated and uses for cathodic protection systems and batteries can also be anticipated.
Employment growth in the face of exchange rate uncertainty: The role of trade and foreign equity finance
Authors: Dhasmana Anubha
Published: March 2021

This paper looks at the role of external trade and foreign equity finance in determining the impact of exchange rate uncertainty on firm‐level employment growth in a major developing economy: India. Exchange rate uncertainty is found to affect firm‐level employment growth adversely on average, but the impact depends upon firm‐level characteristics such as exposure to foreign trade through imports and exports and firm‐level mark‐up. Foreign equity finance reduces the negative impact of exchange rate uncertainty on employment growth but the same cannot be said about access to domestic equity finance.