bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of extraction technique and GC/FID method for the analysis of cannabinoids in Cannabis sativa L. spp. santicha (hemp)
Authors: Baranauskaite Juste , Marksa Mindaugas , Ivanauskas Liudas , Vitkevicius Konradas , Liaudanskas Mindaugas , Skyrius Vaidas , Baranauskas Algirdas 
Published: January 2020

AbstractIntroductionNowadays, the interest in industrial Cannabis sativa L. herb has been increasing in the world. As a result, it is becoming one of the most studied plants due to its multifunctional benefits.ObjectivesTo the best of our knowledge, no study has been conducted so far to determine the impact of extraction methods and conditions on the extraction yields of CBD and CBG from the Cannabis sativa L. ssp. Santhica. Therefore, we aimed to investigate a simple and sensitive GC‐FID method to determine CBD and CBG in hemp extract.MethodsAs regards sample preparation, three extraction techniques were compared, including maceration (ME), ultrasound‐assisted extraction (UAE) and reflux‐heat extraction (RHE), in order to obtain a high recovery of the CBD of interest from the plant material. The GC‐FID method developed in this study represents a powerful tool for the extraction and analysis of non‐psychoactive cannabinoids from hemp varieties to be used for the preparations of extracts with a high content of bioactive compounds for both pharmaceutical and nutraceutical applications.ResultsA simple extraction procedure for CBD and CBG from hemp was also optimized in this work, by using ultrasound assisted extraction method with 96% ethanol, material/solvent ratio 1:10 and extraction time 10 min at room temperature.ConclusionThe overall analytical method was fully validated in agreement with international guidelines. Therefore, proving a powerful and reliable tool for both the selection of hemp varieties with a high content of bioactive compounds and the quality control of its derivatives.
Acetophenone and thiophene side‐arm polyaryleneethynylene conjugated polymers for enrichment of electronic applications
Authors: Arun Kumar Gunasekaran , Chandramohan Ayyavu , Gomathi Priya Ponnaiah , Alagar Muthukaruppan 
Published: January 2020

AbstractIn the present work, a new type of semiconducting acetophenone and thiophene side‐arm based polyaryleneethynylene (PAE) conjugated polymers (CPs) were synthesized using the Heck–Sonogashira cross‐coupling reaction. The new type of monomers and APAEC8, APAEC12, APAEF8, TPAEC8, TPAEC12, and TPAEF8(PAE CPs) were synthesized and characterized using Fourier transform IR, NMR and high resolution mass spectrometry studies. The average molecular weight of the CPs was determined using gel permeation chromatography. The data obtained from optical properties in the UV–visible and photoluminescence spectral studies were used to calculate the values of the Stokes shift. Among the six CPs studied, TPAEC8was found to possess a lower optical band gap (Eg= 2.112 eV) than those of the other CPs. The data obtained from different studies, it was found that TPAEC8exhibits better properties than the other CPs and can be used in the field of organic based photonic, electronic and other sensor applications. © 2020 Society of Chemical Industry
Effect of intramolecular crosslinker properties on the mechanochemical fragmentation of covalently folded polymers
Authors: Levy Avishai , Goldstein Hadar , Brenman Dolev , Diesendruck Charles E. 
Published: January 2020

ABSTRACTThe mechanochemical stability of polymers in solution is enhanced if the chains are covalently folded. Under shear forces, the additional bonds absorb mechanical energy and inhibit unfolding, and as a result, slow down fragmentation. However, not all crosslinkers are equal in terms of their properties (length, strength, etc.). In order to understand the role of these added bonds in the polymers' stability under mechanical stress, a thorough study compares the rate of mechanochemistry on single‐chain polymer nanoparticles which have been folded with crosslinkers with different lengths, strengths, positioning, and valencies. The usage of bonds with different mechanical strengths in the crosslinkers was found to be the most powerful way to change the mechanochemical fragmentation rate. In addition, positioning and valency also play significant role in the mechanical stabilization mechanism. © 2020 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2020 © 2020 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2020, 58, 692–703
New insight into organosilicon plasma‐enhanced chemical vapor deposition layers and their crosslinking behavior by calculating the degree of Si‐networking
Authors: Brenner Thorben , Vissing Klaus 
Published: January 2020

AbstractAn investigation into strongly organosilicon plasma‐polymeric coatings has been performed with the goal of developing a deeper understanding of the relationship between the physical properties and the chemical structure. The overall elemental composition has been analyzed using X‐ray photoelectron spectroscopy (XPS) and micro elemental analysis. Additional XPS peak fitting and Fourier‐transform infrared spectroscopy analysis have been undertaken and physical properties such as Young's modulus and mass density have been determined. The chemical structure of the coatings is discussed taking into account conventional Si–O crosslinking and also an independent second bridge‐building mechanism. Based on this suggestion, a least‐squares algorithm has been used to calculate the network structure including a new index for the degree of crosslinking. This enables very similar plasma‐polymeric coatings to be distinguished.
The strengths and limitations of using biolayer interferometry to monitor equilibrium titrations of biomolecules
Authors: Weeramange Chamitha J. , Fairlamb Max S. , Singh Dipika , Fenton Aron W. , Swint‐Kruse Liskin 
Published: January 2020

AbstractEvery method used to quantify biomolecular interactions has its own strengths and limitations. To quantify protein‐DNA binding affinities, nitrocellulose filter binding assays with 32P‐labeled DNA quantify Kd values from 10−12 to 10−8 M but have several technical limitations. Here, we considered the suitability of biolayer interferometry (BLI), which monitors association and dissociation of a soluble macromolecule to an immobilized species; the ratio koff/kon determines Kd. However, for lactose repressor protein (LacI) and an engineered repressor protein (“LLhF”) binding immobilized DNA, complicated kinetic curves precluded this analysis. Thus, we determined whether the amplitude of the BLI signal at equilibrium related linearly to the fraction of protein bound to DNA. A key question was the effective concentration of immobilized DNA. Equilibrium titration experiments with DNA concentrations below Kd (equilibrium binding regime) must be analyzed differently than those with DNA near or above Kd (stoichiometric binding regime). For ForteBio streptavidin tips, the most frequent effective DNA concentration was ~2 × 10−9 M. Although variation occurred among different lots of sensor tips, binding events with Kd ≥ 10−8 M should reliably be in the equilibrium binding regime. We also observed effects from multi‐valent interactions: Tetrameric LacI bound two immobilized DNAs whereas dimeric LLhF did not. We next used BLI to quantify the amount of inducer sugars required to allosterically diminish protein‐DNA binding and to assess the affinity of fructose‐1‐kinase for the DNA‐LLhF complex. Overall, when experimental design corresponded with appropriate data interpretation, BLI was convenient and reliable for monitoring equilibrium titrations and thereby quantifying a variety of binding interactions.
A summary of the investigation report on the Tianjiayi explosion incident (21 March 2019)
Authors: You Zuoling , Yu Jing , Liu Ying , Zhang Yunrui , Zhang Bo 
Published: January 2020

AbstractA severe explosion occurred on 21 March 2019 at Tianjiayi Chemical Co., Ltd, located in the Xiangshui Eco‐chemical Industrial Park, Jiangsu Province, China, which resulted in 78 deaths, 76 serious injuries, and 640 minor injuries. The explosion caused direct economic losses of RMB 1.98 billion yuan. A summary of the incident investigation report is presented. One direct outcome of the accident was the accumulation of heat in solid waste, which resulted in a temperature increase beyond autoignition temperature, while the indirect root‐causes included deficient safety management, inadequate supervision, lack of safety awareness and other factors. In addition, the administrative and criminal liabilities of responsible personnel and inadequacy of prevention measures is summarized.
Formation control for multiquadrotor aircraft: Connectivity preserving and collision avoidance
Authors: Cong Yongzheng , Du Haibo , Jin Qingchun , Zhu Wenwu , Lin Xiangze 
Published: January 2020

SummaryIn this article, we investigate the formation control problem of multiquadrotor aircraft system subject to connectivity preservation and collision avoidance. First, based on the backstepping design method, a novel formation control algorithm is developed to enable multiquadrotor aircraft to move along the desired trajectory while becoming the predefined formation pattern. Meanwhile, the connectivity of the communication network is maintained and the collision among multiquadrotor is avoided. Second, for each quadrotor's desired attitude obtained by the formation controller, an improved finite‐time attitude tracking law is designed to guarantee that the desired attitude can be tracked by the real attitude in a fast finite time. Finally, a numerical example is given to demonstrate the effectiveness of the proposed algorithms.
The nutrient legacy left by salmon tissue on riparian soils in Southeast Alaska
Authors: D'Amore David V. , Chaloner Dominic T. , Gerig Brandon S. , Berkowitz Jacob F. , Bridgham Scott D. 
Published: January 2020

AbstractSalmon‐derived nutrients (SDN) are a distinctive aquatic subsidy to terrestrial ecosystems. Streamwater nutrient increases in response to SDN have been documented but uncertainties about the magnitude and persistence of their effects in riparian areas remain. A key research gap is the response of specific soil types to the nutrient subsidy over time. To address this question, an Entisol and a Spodosol commonly found in riparian zones of Southeast Alaska were delineated adjacent to streams with abundant spawning salmon for experimental nutrient additions. Salmon nutrient additions were applied to track the fate of N and P through time to investigate the patterns of nutrient retention and loss in the Entisol and Spodosol. Salmon additions to Entisols across eight watersheds revealed a large and consistent residual concentration of available NH4+–N but a high variability in NO3−–N after a 30‐d incubation. A comparison of Entisols and Spodosols in two watersheds tracked salmon tissue additions for ∼1 yr, where nutrient concentrations at 240 d decreased relative to 30 d but a flush of available nutrients occurred at 340 d, with higher values in the salmon‐amended soils. The magnitudes of extractable N and P retained in the extractable fraction were similar in the Entisol and Spodosol but dissolved N loss measured via resin beads at the base of the measurement cores indicated higher leaching of NO3−–N from the surface in Entisols. Identification of specific soil types can advance the understanding of nutrient processing, uptake, and loss from SDN additions on riparian landforms.
A systemic framework to evaluate political clientelism and citizens' subjectivation processes
Authors: Vilchez Virginia Carolina , Paucar‐Caceres Alberto , Werner Katarzyna 
Published: January 2020

AbstractPolitical clientelism and low quality of democracy are recurrent problems in Latin American societies. The purpose of this paper is to understand the complex processes of subjectivation introduced and fostered by various practices of political clientelism. To explore this complexity, a systemic framework encompassing three dimensions of analysis—structural, institutional, and subjective—is adopted. To explore the impact that the subjectivation processes have on the formation of citizenship, we applied the framework examining 18 in‐depth interviews with beneficiaries of the Social Inclusion Plan in San Luis, Argentina. Our results suggest that practices and discourses of political clientelism foster citizens' dependence on the state and government. By focusing on the beneficiaries' perceptions, our findings facilitate a better understanding of the real impact of state policies and help to identify ways to empower low‐income people to exercise their rights and to develop a democratic, less dependent, and mature citizenship.
A systemic approach to achieving population‐level impact in injury and violence prevention
Authors: Smith L. Shakiyla , Wilkins Natalie J. , McClure Roderick J. 
Published: January 2020

AbstractThe contemporary public health model for injury and violence prevention is a four‐step process, which has been difficult to fully actualize in real‐world contexts. This difficulty results from challenges in bridging science to practice and developing and applying population‐level approaches. Prevention programmes and policies are embedded within and impacted by a range of system‐level factors, which must be considered and actively managed when addressing complex public health challenges involving multiple sectors and stakeholders. To address these concerns, a systemic approach to population‐level injury and violence prevention is being developed and explored by the Division of Analysis, Research, and Practice Integration in the National Center for Injury Prevention and Control at the Centers for Disease Control and Prevention. This article makes the case for and provides a high‐level overview of this systemic approach, its various components, and how it is being applied in one governmental unit.
Siliceous fly ash and blast furnace slag based geopolymer concrete under ambient temperature curing condition
Authors: Das Sourav K. , Shrivastava Sandeep 
Published: January 2020

AbstractAbundance of industrial by‐products along with its disposal issues and exploitation of the natural resource of limestone for cement production creates a huge problem throughout the globe. Geopolymer technology could be a worthy solution to these problems by producing concrete utilizing industrial by‐products and resisting the exploration of the natural source of limestone and limiting the greenhouse gas emission. This article presents the observations achieved by replacing siliceous fly ash with ground granulated blast furnace slag (GGBFS). Different mix proportions were prepared to measure the mechanical strength. GGBFS was added in replacement of fly ash in different percentages from 0% to 30%. Two different types of molarity of NaOH solution was used to observe the effect of molarity with the addition of GGBFS. By‐product binders were mixed with alkaline solution by keeping the ratio of mixing of Sodium silicate (Na2SiO3) to sodium hydroxide (NaOH) solution equals to 1.5. Slump cone test, compressive and flexural test was conducted to examine the workability and mechanical strength, respectively. Microstructural analysis was conducted to understand the surface morphology and minerology. Current study shows that with the inclusion of GGBFS to siliceous fly ash based geopolymer concrete compressive and flexural strength equals to 43.61 and 5.45 MPa, respectively, can be achieved at ambient condition which may be feasible for cast‐in situ applications.
Untangling the taxonomy of the Cladrastis clade (Leguminosae: Papilionoideae) by integrating phylogenetics and ecological evidence
Authors: Duan Lei , Harris AJ , Ye Wen , Deng Shuang‐Wen , Song Zhu‐Qiu , Chen Hong‐Feng , Wen Jun 
Published: January 2020

AbstractThe Cladrastis clade is an early‐diverged lineage within the subfamily Papilionoideae of Leguminosae. Several taxonomic uncertainties limit a robust understanding of its taxonomy: (1) Should the genus Platyosprion be resurrected? (2) How should Cladrastis be delimited to maintain the generic monophyly? (3) Is Styphnolobium best classified into two or three sections? We assessed specific/sectional/generic boundaries within this clade by integrating evidence from phylogenetic analyses, morphology, and multivariate ecological methods. With an extensive sampling of the clade, we reconstructed the phylogenies using nrDNA (ITS) and plastid DNA regions (matK, psbA‐trnH, trnL‐F). Based on environmental data for 841 occurrences, clusters of species were sought according to their environmental preferences with the principal component analysis (PCA), and explicit hypotheses on species/sectional boundaries were tested using ecological niche modeling (ENM). A new tribe, Cladrastideae, is established based on the Cladrastis clade with four monophyletic groups: the Cladrastis platycarpa complex, Cladrastis s.str., Pickeringia and Styphnolobium. The C. platycarpa complex constitutes the resurrected genus Platyosprion. The putative species C. chingii, C. parvifolia, C. scandens and C. yungchunii are suggested to be treated as synonyms of Platyosprion platycarpum. Cladrastis is recircumscribed as equal to Cladrastis s.str., with three species from eastern Asia, and one species, C. kentukea, from eastern North America. Styphnolobium is herein classified into three sections: St. sect. Oresbios, St. sect. Styphnolobium and a new section, St. sect. Affine.
Emergent unitarity from the amplituhedron
Authors: Srikant Akshay Yelleshpur 
Published: January 2020

Abstract
We present a proof of perturbative unitarity for planar $$ \mathcal{N} $$
N
= 4 SYM, following from the geometry of the amplituhedron. This proof is valid for amplitudes of arbitrary multiplicity n, loop order L and MHV degree k.
Mitigation of ionospheric scintillation effects on GNSS precise point positioning (PPP) at low latitudes
Authors: Vadakke Veettil Sreeja , Aquino Marcio , Marques Haroldo Antonio , Moraes Alison 
Published: January 2020

AbstractGlobal navigation satellite systems (GNSS) underpin a number of modern life activities, including applications demanding positioning accuracy at the level of centimetres, such as precision agriculture, offshore operations and mining, to name a few. Precise point positioning (PPP) exploits the precision of the GNSS signal carrier phase measurements and may be used to provide the high accuracy positioning needed by these applications. The Earth’s ionosphere is critical in PPP due to its high variability and to disturbances such as scintillation, which can affect the satellite signals propagation and thereby degrade the positioning accuracy, especially at low latitudes, where severe scintillation frequently occurs. This manuscript presents results from a case study carried out at two low latitude stations in Brazil, where a dedicated technique is successfully applied to mitigate the scintillation effects on PPP. The proposed scintillation mitigation technique improves the least square stochastic model used for position computation by assigning satellite and epoch specific weights based on the signal tracking error variances. The study demonstrates that improvements in the 3D positioning error of around 62–75% can be achieved when applying this technique under strong scintillation conditions. The significance of the results lies in the fact that this technique can be incorporated in PPP to achieve the required high accuracy in real time and thus improve the reliability of GNSS positioning in support of high accuracy demanding applications.
WHO guide to good prescribing is 25 years old: quo vadis?
Authors: Tichelaar J. , Richir M. C. , Garner S. , Hogerzeil H. , de Vries Th. P. G. M. 
Published: January 2020

AbstractIntroductionTwenty-five years ago, the World Health Organization (WHO) published the Guide to Good Prescribing (GGP), followed by the accompanying Teacher’s Guide to Good Prescribing (TGGP). The GGP is based on a normative 6-step model for therapeutic reasoning and prescribing, and provides a six-step guide for students to the process of rational prescribing.MethodWe reviewed the need to update both WHO publications by evaluating their use and impact, including new (theoretical) insights and demands. Based on information from literature, Internet, and other (personal) sources, we draw the following conclusions.Results1. An update of the GGP and TGGP, both in terms of content and form, is necessary because of the current need for these tools (irrational medicine use and unavailability of medicines), the lack of similar documents, and the lack of connection with recent developments, such as Internet and modern education; 2. The basic (6-step) model of the GGP is effective in terms of rational prescribing in the undergraduate situation and is still consistent with current theories about (context) learning, clinical decision-making, and clinical practice; 3. The dissemination and introduction of the GGP and TGGP in education has been successful so far, but is still not optimal because of lack of support and cooperation.ConclusionsOn the basis of the evaluation results, a plan for the revision of the GGP and TGGP is presented.
Defining and measuring imaging appropriateness in low back pain studies: a scoping review
Authors: Yates Mark , Oliveira Crystian B. , Galloway James B. , Maher Chris G. 
Published: January 2020

Abstract
Purpose
Patients with low back pain (LBP) rarely have serious underlying pathology but frequently undergo inappropriate imaging. A range of guidelines and red flag features are utilised to characterise appropriate imaging. This scoping review explores how LBP imaging appropriateness is determined and calculated in studies of primary care practice.

Methods
This scoping review builds upon a previous meta-analysis, incorporating articles identified that were published since 2014, with an updated search to capture articles published since the original search. Electronic databases were searched, and citation lists of included papers were reviewed. Inclusion criteria were studies assessing adult LBP imaging appropriateness in a primary care setting. Twenty-three eligible studies were identified.

Results
A range of red flag features were utilised to determine imaging appropriateness. Most studies considered appropriateness in a binary manner, by the presence of any red flag feature. Ten guidelines were referenced, with 7/23 (30%) included studies amending or not referencing any guideline. The method for calculating the proportion of inappropriate imaging varied. Ten per cent of the studies used the total number of patients presenting with LBP as the denominator, suggesting most studies overestimated the rate of inappropriate imaging, and did not capture where imaging is not performed for clinically suspicious LBP.

Conclusion
Greater clarity is needed on how we define and measure imaging appropriateness for LBP, which also accounts for the problem of failing to image when indicated. An internationally agreed methodology for imaging appropriateness studies would ultimately lead to an improvement in the care delivered to patients.

Graphic abstract

These slides can be retrieved under Electronic Supplementary Material.