bluuebunny/crossref_metadata_2025_split huggingface dataset:
Asymptotic stability and stabilization of discrete‐time switched systems with time‐varying delay
Authors: Charqi Mohammed , Tissir El Houssaine , Boukili Bensalem 
Published: October 2020

SummaryThis article deals with the problems of stability and stabilization for a class of discrete‐time switched systems with time‐varying delay under arbitrary switching signal. First, sufficient conditions guaranteeing the asymptotic stability of the unforced system are developed, by using the switched Lyapunov‐Krasovskii functional method. Then, based on the obtained results, a state feedback controller is designed in order to ensure the asymptotic stability of the closed‐loop system. Furthermore, slack variables are introduced for more relaxation. The proposed approach is proved to have some less conservative results than some existing works. Finally, numerical examples are provided to illustrate the effectiveness and the merit of the proposed method and to compare the obtained results with some previous works in the literature.
Interventions to improve early detection of childhood cancer in low‐ and middle‐income countries: A systematic review
Authors: Zabih Weeda , Thota Anilkrishna B. , Mbah Glenn , Freccero Piera , Gupta Sumit , Denburg Avram E. 
Published: October 2020

AbstractBackgroundChildhood cancer outcomes in low‐ and middle‐income countries (LMICs) lag behind those in high‐income countries (HICs), in part due to late presentation and diagnosis. Though several interventions targeting early detection of childhood cancer have been implemented in LMICs, little is known about their efficacy.MethodsWe conducted a systematic review to identify studies describing such interventions. We searched multiple databases from inception to December 4, 2019. Studies were included if they reported on LMIC interventions focused on: (a) training of health care providers on early recognition of childhood cancer, or (ii) public awareness campaigns. We used preferred reporting items for systematic reviews and meta‐analyses (PRISMA) guidelines to conduct our review. The risk of bias in nonrandomized studies of interventions (ROBINS‐I) checklist was used to assess quality of studies.ResultsTwelve studies met inclusion criteria (n = 5 full text, n = 7 abstract only). Five studies focused on retinoblastoma only, while the others focused on all types of childhood cancer. The majority studied multiple interventions of which early detection was one component, but reported overall outcomes. All identified studies used pre‐post evaluative designs to measure efficacy. Five studies reported statistically significant results postintervention: decrease in extraocular spread of retinoblastoma, decrease in rates of refusal/abandonment of treatment, increase in number of new referrals, increase in knowledge, and an absolute increase in median 5‐year survival. Other studies reported improvements without tests of statistical significance. Two studies reported no difference in survival postintervention. The ROBINS‐I checklist indicated that all studies were at serious risk of bias.ConclusionThough current evidence suggests that LMIC interventions targeting early detection of childhood cancer through health professional training and/or public awareness campaigns may be effective, this evidence is limited and of poor quality. Robust trials or quasi‐experimental designs with long‐term follow up are needed to identify the most effective interventions. Such studies will facilitate and inform the widespread uptake of early detection interventions across LMIC settings.
Effects of radiation type and dose on the properties of selected polymers
Authors: Burgstaller Christoph , Höftberger Thomas , Gallnböck‐Wagner Bernhard , Stadlbauer Wolfgang 
Published: October 2020

AbstractUsing ionizing radiation to sterilize medical and health care products is a widespread and well established approach, as products can be treated in their final shipping container without any residuals. During irradiation, the product materials will undergo some changes due to the absorbed energy, which have to be assessed during product qualification in order to specify a maximum allowable dose for the product. However, there is a lack of a systematic approach studying polymers in regard to dose ranges encountered and all types of ionizing radiation. Therefore, the aim of this work was to investigate the influence of radiation dose and source on the resulting properties of various polymers, which were already brought into final shape via injection molding, and to compare these effects found in the mechanical and rheological properties as well as their appearance. We found, that the mechanical properties of most investigated polymers are not influenced, except for polypropylene, but that yellowing was a pronounced effect in all the cases. The differences in polymer properties due to the radiation sources are small, only some materials exhibit more degradation by gamma irradiation due to the lower dose rate applied in comparison to x‐ray and e‐beam irradiation.
Evaluation of Guideline Recommendations for Dual Antipseudomonal Therapy in Hospitalized Adults with Pneumonia Using Combination Antibiograms
Authors: Luu Quyen , Vitale Kaylee , Shan Guogen , Jayakumar Rebecca , Viswesh Velliyur 
Published: October 2020

BackgroundGuidelines for pneumonia recommend empiric dual antipseudomonal therapy in patients with specific risk factors. However, there is lack of consensus on when to use dual antipseudomonal therapy as the recommendations are rated as weak, based on low‐quality evidence.ObjectivesThe objectives of this study were to develop combination antibiograms to assess the susceptibility of Pseudomonas aeruginosa (P. aeruginosa) in respiratory cultures to combinations of empiric antibiotics and to use combination antibiograms to delineate the impact of specific risk factors for which guidelines recommend dual antipseudomonal therapy.MethodsA retrospective cohort study was conducted of adults hospitalized with pneumonia with positive respiratory cultures for P. aeruginosa between September 2014 and September 2018. Data collected included demographics, antimicrobial susceptibility results, and risk factors for which guidelines recommend dual antipseudomonal therapy. Combination antibiograms were developed and logistic regression was performed to identify risk factors for nonsusceptibility to beta‐lactams.ResultsEight hundred nineteen patients were included and 72% received antibiotics. Beta‐lactam susceptibility ranged from 58% to 69% and addition of a fluoroquinolone or aminoglycoside resulted in statistically significant increases in susceptibility. However, only addition of tobramycin or amikacin provided susceptibility rates approaching or exceeding 90% stratified by pneumonia type and risk factors. Presence of guideline‐based risk factors generally resulted in reduced susceptibility rates. Logistic regression identified three risk factors associated with nonsusceptibility to beta‐lactams: intravenous antibiotics in the previous 90 days, nursing home residence, and mechanical ventilation at onset. The cumulative presence of each additional risk factor affected beta‐lactam susceptibility rates, which were 93% in the absence of any risk factors and 39% when all three risk factors co‐existed.ConclusionsRisk factors necessitating dual antipseudomonal therapy for pneumonia should be locally validated. When dual antipseudomonal therapy is indicated, tobramycin or amikacin have the best likelihood of providing adequate in vitro activity.
Poly(methyl methacrylate) bone cement, its rise, growth, downfall and future
Authors: Soleymani Eil Bakhtiari Sanaz , Bakhsheshi‐Rad Hamid Reza , Karbasi Saeed , Tavakoli Mohamadreza , Hassanzadeh Tabrizi Sayed Ali , Ismail Ahmad Fauzi , Seifalian Alexander , RamaKrishna Seeram , Berto Filippo 
Published: October 2020

AbstractPoly(methyl methacrylate) (PMMA)‐based bone cements (BCs) can be defined as a family of materials that consist of powder and liquid phases which after mixing form a plastic paste that can self‐set once implanted in the human body. PMMA‐based BCs are easily molded and adapted to complex bone cavities or used in orthodontic applications to restore dental damage. The main advantages of the use of cement are the excellent primary fixation between bone and implant and, therefore, the faster recovery of the patient. Despite the initial success rate of implant fixation with BCs, they have some disadvantages such as local tissue damage due to exothermic polymerization reactions, mechanical mismatch between native bone and cement, lack of bone regeneration and bioactivity and poor mechanical properties which may cause the failure of the BCs. BCs are still considered as a top option for bone repair. Due to the disadvantages highlighted, research has focused on alternative materials used with PMMA‐based BCs. This review aims to critically review the BCs and emerging materials used in combination with PMMA‐based BCs. These materials include titania, apatite–wollastonite (A‐W), glass ceramic (GC) and hydroxyapatite (HA). The review discusses the properties of these materials and their pathway to clinical study. Among the various kinds of reinforcement, HA has been extensively used. So, in this review, we compare the effects of HA as reinforcement in PMMA‐based BCs. Upcoming study of PMMA‐based BCs should concentrate on trialing combinations of these reinforcing agents as this might improve beneficial characteristics. © 2020 Society of Industrial Chemistry
Poly(vinyl alcohol)/graphene oxide nanocomposite hydrogel with catalytic activity: the removal behavior and dual adsorption/catalytic degradation mechanism for dye wastewater
Authors: Yu Yaru , Zhao Xiaowen , Ye Lin 
Published: October 2020

AbstractThe treatment of dye wastewater with traditional adsorption materials usually proceeds slowly with low removal efficiency and without completely eliminating dye molecules, leading to secondary pollution. In this work, poly(vinyl alcohol)/graphene oxide@tetraamino iron phthalocyanine (PVA/GO@TAFePc) nanocomposite hydrogels with catalytic activity were prepared via an in situ crosslinking method. Through interfacial covalent and π–π interactions, TAFePc was loaded onto GO layers with a high loading ratio, and GO@TAFePc was exfoliated and uniformly dispersed in the matrix. With increasing GO@TAFePc hybrid content, the pore size increased and a loose network structure was formed for the hydrogels, while the specific surface area rose significantly by using the hydrogel in a dye removal process, the removal rate of methylene blue (MB) increased sharply with contact time, reaching 98% in the presence of H2O2 with good reusability, and high removal efficiency was achieved for different dyes. The large surface area of the hydrogel was beneficial for MB adsorption. Meanwhile, under catalysis of TAFePc, a large amount of high activity ·OH was produced by H2O2 so as to degrade the MB molecules rapidly. Therefore, the MB degradation process for the composite hydrogel was ascribed to a dual adsorption/catalytic degradation mechanism. © 2020 Society of Industrial Chemistry
Quality of death: The unspoken experiences of patients with advanced cancers in India – An exploratory qualitative study
Authors: Sudhakar Revathy , Veeraiah Surendran , Ganesan Prasanth , Balakrishnan Kalpana 
Published: October 2020

AbstractObjectiveEnd‐of‐life (EOL) care is a developing concept in India, with well‐established practices in certain states like Kerala, but not in all the states. As there is a substantial stigma associated with death discussion across the Indian population, the experiences of caregivers of people with advanced cancer have not been explored. Our aim in this study was to explore the experience and perceptions of caregivers of people diagnosed with advanced cancer regarding the quality of the individuals' death.MethodsAn exploratory study where the caregivers (n = 108) of advanced cancer patients, who died either during hospitalization or at home, were interviewed to assess quality of death (QOD), using an open‐ended question to explore the sufferings of the patients in the final days and caregivers' coping mechanism.ResultsMajority of the patients died at home (n = 79, 73.1%). The thematic analysis of the transcripts resulted in seven sub‐themes, which were categorized under four major themes, namely ‘bodily discomfort’, ‘psychological experiences’ with the sub‐themes resilience and existential distress, ‘awareness of prognoses’ with the sub‐themes aware, unaware and conjecture, and ‘carers coping’ with the sub‐themes perceived strain and contentment.ConclusionPatients under EOL care experience physical and psychological suffering, as reported by the caregivers. Efforts must be undertaken to reduce suffering by means of improving focus on and strengthening symptom management and enhancing psychosocial support, for optimally utilizing the available interventions to manage the physical symptoms and to address the psychosocial issues.
On the Gravitational Force on Anti‐Matter
Authors: Caldwell Allen , Dvali Gia 
Published: October 2020

AbstractA number of experiments are currently underway on antimatter, particularly anti‐hydrogen, to test whether the fundamental interactions behave the same way as for matter. Here we present a simple argument showing that a bound on a difference in gravitational forces exerted on matter and antimatter is already so severe that is goes well beyond the sensitivity of the above measurements.
Magnitude and decline of pesticide co‐formulant residues in vegetables and fruits: results from field trials compared to estimated values
Authors: Balmer Marianne E , Janser Daniel , Schaller Ulrich , Krauss Jürgen , Geiser H Christoph , Poiger Thomas 
Published: October 2020

AbstractBACKGROUNDThe application of plant protection products (PPPs) leads to the formation of residues in treated crops. Even though PPPs contain considerable amounts of co‐formulants, regulation and monitoring of residues normally focus on the active substances (a.s.) only. For our study we selected four commonly used co‐formulants (three anionic surfactants and one organic solvent) and investigated the formation and decline of residues in vegetables and apples under field conditions. The aims were to characterize the behavior of co‐formulant residues on crops and to provide a basis for future investigations on consumer exposure.RESULTSThe development of robust and sensitive analytical methods allowed the quantification of residues in the low μg/kg‐level. After treatment with PPPs, co‐formulants were detected up to approximately 10 mg kg–1 in vegetables. In general, these residues declined fast with half‐lives of a few days. Wash‐off and volatilization were identified as important removal processes for anionic surfactants and the organic solvent, respectively. However, in specific crops (parsley and celery), organic solvent residues were still considerable (≈2 mg kg–1) 2 weeks after treatment. We further demonstrate that it is feasible to estimate co‐formulant residues using publicly available data on pesticide a.s.CONCLUSIONTo date no information on co‐formulant residues in food is available. The findings from our field trials, as well as the presented approach for the prediction of residues, provide key elements for future consideration of consumer exposure to PPP co‐formulants. © 2020 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
On the number of bins in a rank histogram
Authors: Heinrich Claudio 
Published: October 2020

AbstractRank histograms are popular tools for assessing the reliability of meteorological ensemble forecast systems. A reliable forecast system leads to a uniform rank histogram, and deviations from uniformity can indicate miscalibrations. However, the ability to identify such deviations by visual inspection of rank histogram plots crucially depends on the number of bins chosen for the histogram. If too few bins are chosen, the rank histogram is likely to miss miscalibrations; if too many are chosen, even perfectly calibrated forecast systems can yield rank histograms that do not appear uniform. In this paper we address this trade‐off and propose a method for choosing the number of bins for a rank histogram. The goal of our method is to select a number of bins such that the intuitive decision whether a histogram is uniform or not is as close as possible to a formal statistical test. Our results indicate that it is often appropriate to choose fewer bins than the usual choice of ensemble size plus one, especially when the number of observations available for verification is small.
E‐Bayesian estimation and associated properties of simple step–stress model for exponential distribution based on type‐II censoring
Authors: Nassar Mazen , Okasha Hassan , Albassam Mohammed 
Published: October 2020

AbstractIn this paper, expected Bayesian (E‐Bayesian) estimation for the simple step–stress model based on type‐II censoring scheme is considered. The case of exponential distribution for the underlying lifetimes is considered assuming a cumulative exposure model. The E‐Bayesian estimation is discussed by considering three different prior distributions for the hyperparameters. The E‐Bayesian estimators as well as the corresponding E‐posterior risks are obtained by using squared error and linear‐exponential (LINEX) loss functions. Some properties of the E‐Bayesian estimators are also derived. We conduct a simulation study to compare the various estimators and a simulated and real data sets are analyzed to show the applicability of the different estimators. The numerical results show that the E‐Bayesian estimators perform better than the classical and Bayesian estimators.
Using solid‐state nuclear magnetic resonance to rationalize best efficiency of 2,6‐dihydroxybenzoic acid over other 2,X‐dihydroxybenzoic acid isomers in solvent‐free matrix‐assisted laser desorption/ionization of poly(ethylene glycol)
Authors: Pizzala Hélène , Chendo Christophe , Charles Laurence 
Published: October 2020

RationaleAmong isomers of dihydroxybenzoic acid (DHB), 2,5‐DHB is often the most efficient matrix in matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) for a great variety of compounds. Yet, when performing solvent‐free MALDI, 2,6‐DHB yields better results for poly(ethylene glycol [PEG]). This intriguing feature is explored here using solid‐state nuclear magnetic resonance (NMR).MethodsTernary mixtures were prepared by grinding 2,X‐DHB (X = 3–6), poly(ethylene glycol) (Mn = 2000 g mol−1) and lithium fluoride (LiF) in a matrix/analyte/salt molar ratio of 50/1/10 for 16 min under a controlled atmosphere. After mixing, a few grains were applied to the MALDI target for MS analysis, whereas the major part of the ground sample was transferred into rotors to perform 13C, 7Li, and 19F NMR experiments.ResultsLithiated PEG chains are mainly formed with 2,6‐DHB in solvent‐free MALDI, but their abundance increases with 2,3‐DHB and 2,4‐DHB when water uptake is favored by a humid atmosphere. Solid‐state NMR shows that grinding 2,6‐DHB‐based samples in atmospheric conditions leads to a solid phase in which the matrix, PEG, and salt molecules exhibit a high mobility compared with systems involving other 2,X‐DHB isomers. This mobile environment would favor (as a solvent) LiF dissociation and best promote PEG cationization.ConclusionsComplementary data in 13C, 7Li, and 19F NMR spectra are consistent with the formation of a solid phase of high mobility composed of 2,6‐DHB, PEG, and the two salt components that ultimately favor the production of lithiated PEG chains.
A sustainability assessment of an in situ ultrasonic reactor for remediation of PFAS‐contaminated groundwater
Authors: Laramay Fiona , Crimi Michelle 
Published: October 2020

AbstractThe environmental remediation industry has increasingly considered the sustainability impacts of remediation systems. The ideal remediation system has a greater environmental benefit than detriment. While sustainable systems are increasingly available for many contaminants, per‐ and polyfluoroalkyl substances have presented new challenges for remediation practitioners seeking effective and sustainable systems. Here the sustainability and cost impacts of an ultrasonic reactor installed in a horizontal well (referred to as the In situ reactor technology [inSRT] system) at a hypothetical site are quantified and compared to hypothetical pump‐and‐treat (PT) system impacts. Direct costs of emissions from remediation were compared using LCOE data. The indirect impacts from pollution were quantified based on literature values. The results showed that the InSRT system had lower lifecycle impacts and costs compared to the PT system when each was considered under individually optimal conditions. InSRT was found to meet sustainability goals when used in a low hydraulic conductivity source zone and the PT system lifecycle impacts were reduced when the system was used in a high‐hydraulic conductivity area.
Concrete screws as a post‐installed punching shear reinforcement
Authors: Walkner Rupert , Spiegl Matthias , Feix Jürgen 
Published: October 2020

AbstractThe strengthening of concrete structures is becoming more and more important. To achieve this need for strengthening measures, technically innovative, simple and economical systems for subsequent strengthening are required. At the University of Innsbruck, a system for subsequent strengthening of the punching shear zone through the installation of concrete screws has been developed. These screws are installed from the soffit side of the slab in vertically predrilled holes and are arranged concentrically around the support. This paper discusses the results of four test series, with a total of 21 specimens used to develop the system. The system, which can be very easily installed, demonstrates a significant increase of the shear punching capacity and a reduction in brittle failure modes. In addition, cyclic loading with typical levels of service load has no negative effect on the effectiveness of the system. Finally, the influence of the flexural reinforcement ratio on the effectiveness of the strengthening system was investigated.
Effect of sulfonamide class of antibiotics on a bacterial consortium isolated from an anaerobic digester of a sewage treatment plant
Authors: Naquin Ethan , Soorya Hiba , Oubre Christopher , Rogers Sarah , Boopathy Raj 
Published: October 2020

AbstractThe effect of the sulfonamide class of antibiotics, namely, trimethoprim and sulfamethoxazole (TMP–SMX) on growth and metabolism of a bacterial consortium isolated from an anaerobic digester of a sewage treatment plant, was investigated. The bacterial consortium was exposed to various concentrations of TMP–SMX. The results indicated that there was no effect of TMP and SMX on the bacterial consortium in terms of bacterial growth and carbon and nitrate removal even at the highest concentration tested at 250 mg/L. The carbon removal was more than 90%, and the nitrate removal was more than 87% in all culture conditions. A pure culture was isolated and identified as Leuconostoc mesenteroides from the consortium, which was able to use TMP and SMX as the sole source of carbon for growth. This pure culture has the sul1 gene to show resistance to these antibiotics. This research could be used in the anaerobic digestion process to degrade various classes of sulfonamide antibiotics before the treated sludge is discharged into the environment to reduce the concentration of TMP and SMX.