bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of compatibilizer and multifunctional additive loadings on flame retardation, plasticization, and impact modification of polylactide and poly(butylene adipate‐co‐terephthalate) biodegradable blends
Authors: Phetwarotai Worasak , Suparanon Tunsuda , Phusunti Neeranuch , Potiyaraj Pranut 
Published: June 2020

The poor compatibility and flame retardation of polylactide (PLA) and poly(butylene adipate‐co‐terephthalate) (PBAT) blends seriously limit their applications. This study focused on the mechanical properties and flame retardancy of a PLA/PBAT blend under the influence of different levels of compatibilizer and multifunctional additives (MFA). PLA and PBAT were successfully compatibilized via reactive blending in a twin‐screw extruder. The flame retardation, flexibility, and impact toughness of the compatibilized blend were improved by the presence of tricresyl phosphate (TCP) and triethyl citrate (TEC). Separately and in combination, the two additives played crucial roles in flame retardant effectiveness, plasticization, and impact modification. The compatibilized blend displayed a UL‐94 V‐0 rating and exhibited a high limiting oxygen index (LOI). A slight reduction in thermal stability was exhibited when 20 phr TCP was incorporated into the blend. During combustion, an integrated char layer formed on the compatibilized blend surface and retarded flammability. The combination of TCP and TEC not only significantly improved dripping behavior and flame‐retardant properties of the compatibilized blend but also cooperatively enhanced the elongation at break and impact strength without impacting tensile strength, Young's modulus, LOI value, and thermal stability. The failure behavior of the blend changed from brittle to ductile, as evidenced by SEM, which revealed elongated fibrils after tension. These characteristics were associated with the presence of the MFAs and the improved interfacial adhesion between PLA and PBAT. As a result, flame retardation, flexibility, and impact resistance were enhanced. These improvements permit the wider application of PLA, especially in the electronic and automotive fields.HighlightsCompatibilized PLA/PBAT blend achieved the V‐0 rating and had a high LOI.Both TCP and TEC could be used as multifunctional additives (MFAs) in the compatibilized blend.Combination of MFAs synergistically enhanced elongation at break and impact strength without impacting other properties of the blends.These improvements permit the wider application of PLA, especially in the electronic and automotive fields.
Effect of the COVID‐19 pandemic on anxiety among children with cystic fibrosis and their mothers
Authors: Pınar Senkalfa Burcu , Sismanlar Eyuboglu Tugba , Aslan Ayse T. , Ramaslı Gursoy Tugba , Soysal Azime S. , Yapar Dilek , İlhan Mustafa N. 
Published: June 2020

AbstractBackgroundWe aimed to evaluate anxiety among children with cystic fibrosis (CF) and their mothers related to the COVID‐19 pandemic.MethodsA total of 45 patients with CF and their mothers were enrolled in the study together with 90 age‐matched healthy children and their mothers as a control group. The State and Trait Anxiety Inventory (STAI) was administered by teleconference with children aged 13 to 18 years old and their mothers. The STAI for children was administered with children aged 9 to 12 years. Results were compared with age‐matched healthy children and their mothers. The relationship between anxiety scores of children with CF and their mothers was evaluated by comparing with clinical data of children with CF. At the conclusion of the teleconference, mothers were asked whether their anxiety had changed as a result of the interview.ResultsIt was found that healthy children aged 13 to 18 years had higher state anxiety scores than age‐matched children with CF. Mothers of children with CF had higher trait anxiety scores, especially those of children aged 0 to 12 years, than mothers of healthy children (P < .05). For mothers of children with CF, state anxiety scores were higher among those whose children had chronic Pseudomonas infection (P < .05). Most mothers of children with CF stated that their anxiety decreased following the interview.ConclusionThe COVID‐19 pandemic may increase anxiety among mothers of children with CF as well those with healthy children. However, COVID‐19 had no effect on the anxiety of children with CF. Informing parents of children with CF about COVID‐19 by teleconference may decrease anxiety.
A shift of dynamic equilibrium between the KIT active and inactive states causes drug resistance
Authors: Srikakulam Sanjay K. , Bastys Tomas , Kalinina Olga V. 
Published: June 2020

AbstractTyrosine phosphorylation, a highly regulated post‐translational modification, is carried out by the enzyme tyrosine kinase (TK). TKs are important mediators in signaling cascades, facilitating diverse biological processes in response to stimuli. TKs may acquire mutations leading to malignancy and are viable targets for anti‐cancer drugs. Mast/stem cell growth factor receptor KIT is a TK involved in cell differentiation, whose dysregulation leads to various types of cancer, including gastrointestinal stromal tumors, leukemia, and melanoma. KIT can be targeted by a range of inhibitors that predominantly bind to the inactive state of the enzyme. A mutation Y823D in the activation loop of KIT is known to be responsible for the loss of sensitivity to some drugs in metastatic tumors. We used all‐atom molecular dynamics simulations to study the impact of Y823D on the KIT conformation and dynamics and compared it to the effect of phosphorylation of Y823. We simulated in total 6.4 μs of wild‐type, mutant and phosphorylated KIT in the active‐ and inactive‐state conformations. We found that Y823D affects the protein dynamics differently: in the active state, the mutation increases the protein stability, whereas in the inactive state it induces local destabilization, thus shifting the dynamic equilibrium towards the active state, altering the communication between distant regulatory regions. The observed dynamics of the Y823D mutant is similar to the dynamics of KIT phosphorylated at position Y823, thus we hypothesize that this mutation mimics a constitutively active kinase, which is not responsive to inhibitors that bind its inactive conformation.
Characterization of maitotoxin‐4 (MTX4) using electrospray positive mode ionization high‐resolution mass spectrometry and UV spectroscopy
Authors: Pisapia Francesco , Sibat Manoëlla , Watanabe Ryuichi , Roullier Catherine , Suzuki Toshiyuki , Hess Philipp , Herrenknecht Christine 
Published: June 2020

RationaleThe dinoflagellate genera Gambierdiscus and Fukuyoa are producers of toxins responsible for Ciguatera Poisoning (CP). Although having very low oral potency, maitotoxins (MTXs) are very toxic following intraperitoneal injection and feeding studies have shown they may accumulate in fish muscle. To date, six MTX congeners have been described but two congeners (MTX2 and MTX4) have not yet been structurally elucidated. The aim of the present study was to further characterize MTX4.MethodsChemical analysis was performed using liquid chromatography coupled to a diode‐array detector (DAD) and positive ion mode high‐resolution mass spectrometry (LC/HRMS) on partially purified extracts of G. excentricus (strain VGO792). HRMS/MS studies were also carried out to tentatively explain the fragmentation pathways of MTX and MTX4.ResultsThe comparison of UV and HRMS (ESI+) spectra between MTX and MTX4 led us to propose the elemental formula of MTX4 (C157H241NO68S2, as the unsalted molecule). The comparison of the theoretical and measured m/z values of the doubly charged ions of the isotopic profile in ESI+ were coherent with the proposed elemental formula of MTX4. The study of HRMS/MS spectra on the tri‐ammoniated adduct ([M – H + 3NH4]2+) of both molecules gave additional information about structural features. The cleavage observed, probably located at C99–C100 in both MTX and MTX4, highlighted the same A‐side product ion shared by the two molecules.ConclusionsAll these investigations on the characterization of MTX4 contribute to highlighting that MTX4 belongs to the same structural family of MTXs. However, to accomplish a complete structural elucidation of MTX4, an NMR‐based study and LC/HRMSn investigation will have to be carried out.
Preparation of Graphene ‐ Like Carbon Composites (GCC) by Hummers Method Using Fly Ash as Carbon Source and Its Removal of Lead from Wastewater
Authors: Shen Huanglin , Xie Wenyu , Zhao Mengqi , Su Zhi , Su Xintai , Lin Zhang 
Published: June 2020

AbstractIn this paper, fly ash (FA) was successfully prepared into graphene‐like carbon composite materials (GCC) with good adsorption properties for heavy metals by alkali activation‐Hummer oxidation method. What's more, the sulfate in the waste liquid can be collected by concentration, and sulfuric acid can be recycled several times after treatment. FA has been fully recycled in an inexpensive and environmentally friendly way. Compared with FA, the specific surface area of GCC increased about 50 times, and the pore size decreased from 9.49 nm to 4.5 nm. The adsorbing amount of GCC could attain 79.38 mg g−1 within 90 min at pH=6. The experimental data of lead adsorption by GCC showed that the results were very consistent with the Freundlich adsorption model. The adsorbent prepared in this work has a good application prospect in water pollution control, which provides a new approach for resource recovery of FA.
Synthesis, Chemotherapeutic Screening and Docking Studies of NSAID Inserted Peptide‐Triazole Hybrid Molecules
Authors: Srinivas Suryapeta , Neeraja Papigani , Naveen Kuntala , Banothu Venkanna , Dubey Pramod K. , Mukkanti Khagga , Pal Sarbani 
Published: June 2020

AbstractA series of peptide based new tryptophan‐1,2,3‐triazole‐naproxen derivatives were explored as prospective antibacterial / cytotoxic agents. These derivatives were prepared via a multi‐step method involving CuAAC as a key step and characterized by spectral data. The synthesized derivatives were evaluated for their antimicrobial activities against one Gram‐positive (S. aureus) and three Gram‐negative (E. coli, K. pneumoniae and P. vulgaris) bacteria using an agar‐well diffusion protocol where amoxycillin was used as a reference compound. Most of these compounds showed antibacterial activities when tested at 0.4 mg / 50 μl concentration. Compound 9 e i. e. N‐(1‐amino‐1‐oxo‐3‐phenylpropan‐2‐yl)‐3‐(1‐((1‐(2‐((2‐chlorophenyl)amino)‐2‐oxoethyl)‐1H‐1,2,3‐triazol‐4‐yl)methyl)‐1H‐indol‐3‐yl)‐2‐(2‐(6‐methoxynaphthalen‐2‐yl)propanamido)propanamide exhibited good activities against all the strains. The potential DNA gyrase inhibitory activity of this compound was investigated by molecular docking studies carried out using Autodock Vina software. Compound 9 e showed an impressive ΔGbind of −10.0 kcal/mol. The cytotoxicity of the obtained compounds was also assessed against A549 cancer cell line (human lung carcinoma) by an MTT assay. Several of these compounds showed promising activity while 9 e showed lowest IC50 value. A brief SAR for both antibacterial / cytotoxic activities of compounds tested is presented. Overall, compound 9 e has emerged as an initial hit molecule for further study.
Insight into the Alkylation‐Efficiency of Methanol with Toluene over HZSM‐5 Zeolite II: Acidic Properties also Significantly Affects Reacting‐Pathways
Authors: Li Junhui , Gong Qing , Jia Wenzhi , Zhu Xilin , Tang Jia , Cai Jinjun , Zhang Rui , Wang Conghui , Hu Zhonghua , Zhu Zhirong 
Published: June 2020

AbstractHere the effect of HZSM‐5 acid‐properties on the reacting‐pathways in the reaction system of toluene alkylation with methanol was studied detailedly, from the aspects of acidic type (Brönsted/Lewis), density, strength and location. A reasonable acid‐properties as following is an indispensable support to achieve a high methanol alkylation‐efficiency: not only the relatively high ratios of both Brönsted/Lewis and external/internal acid‐amount, but also both modest density and weak‐medium strength. Firstly, because alone Lewis acidity is almost inactive to aromatic alkylation, meaning Brönsted acid‐sites are indispensable. Secondly, an extremalization in either acidic density or strength is disadvantageous to aromatic alkylation, but encourages the conversion of methanol to olefins (MTO). Besides, the external acid‐sites in a relatively relaxed microenvironment are more favorable to catalyze aromatic‐alkylation than those inside channel where the strong diffusion/space restriction to aromatic‐molecules but foments MTO side‐reaction. Our work may provide a theoretical guidance for improving the methanol alkylation‐efficiency in this reaction system.
‘Off‐the‐Shelf’ Material for Ratiometric Sensing of Phosgene at Nanomolar Level Both in Solution and Gaseous Phase
Authors: Dey Nilanjan 
Published: June 2020

AbstractCommercially available fluorogenic probe, 2‐ (2‐hydroxyphenyl) benzimidazole has been involved in detecting phosgene via ratiometric color changing response (cyan to blue). Mechanistic studies indicate formation of oxazolidone ring via double carbamylation reaction with phosgene, which significantly curb the extent of excited‐state proton transfer. On the other hand, involvement of weakly alkaline phenolic group as nucleophilic site ensures high specificity over structurally similar competitive analyte, such as triphosgene. Moreover, the present system can detect as low as 14.5 nM phosgene, which is ∼140 fold lower than the threshold value (2 ppm), known to cause immediate danger to health and life (IDLH). Also, detection of phosgene in gaseous state was achieved using dye‐coated paper strips (LOD: ∼0.16 ppm). A quenching in blue fluorescence was noticed when the strips were exposed to phosgene gas phase. Since no sophisticated analytical instrument, trained personnel or constant power supply is required, these paper‐based sensory devices are inexpensive and highly user‐friendly.
Microfluidic Templating of Spatially Inhomogeneous Protein Microgels
Authors: Xu Yufan , Jacquat Raphaël P. B. , Shen Yi , Vigolo Daniele , Morse David , Zhang Shuyuan , Knowles Tuomas P. J. 
Published: June 2020

Abstract3D scaffolds in the form of hydrogels and microgels have allowed for more native cell‐culture systems to be developed relative to flat substrates. Native biological tissues are, however, usually spatially inhomogeneous and anisotropic, but regulating the spatial density of hydrogels at the microscale to mimic this inhomogeneity has been challenging to achieve. Moreover, the development of biocompatible synthesis approaches for protein‐based microgels remains challenging, and typical gelation conditions include UV light, extreme pH, extreme temperature, or organic solvents, factors which can compromise the viability of cells. This study addresses these challenges by demonstrating an approach to fabricate protein microgels with controllable radial density through microfluidic mixing and physical and enzymatic crosslinking of gelatin precursor molecules. Microgels with a higher density in their cores and microgels with a higher density in their shells are demonstrated. The microgels have robust stability at 37 °C and different dissolution rates through enzymolysis, which can be further used for gradient scaffolds for 3D cell culture, enabling controlled degradability, and the release of biomolecules. The design principles of the microgels could also be exploited to generate other soft materials for applications ranging from novel protein‐only micro reactors to soft robots.
Sedimentation rate of settleable particulate matter in Santiago city, Chile
Authors: Morales‐Casa Verónica , Barraza Francisco , Collante Elizabeth , Ginocchio Rosanna , Jorquera Héctor , Lambert Fabrice , Ospina Esteban , Sáez‐Navarrete César , Varas José 
Published: June 2020

AbstractSettleable particulate matter (SPM) is an atmospheric pollutant harmful to human health and the environment in high concentrations. Despite this fact, no up‐to‐date information on SPM levels exists for the capital of Chile, Santiago (7 million inhabitants). To address this knowledge gap, SPM sedimentation rates, including soluble and insoluble components, were measured at three different urban sites from July to November of 2016. We compare the measurements with ambient and meteorological information, as well as urban typology settings.Our results indicate SPM deposition rates between 2.5 and 3.9 g/(m2·30 days). Only one site exceeded the national limit of 4.5 g/(m2·30 days), but we found an increasing trend in all three sites. SPM and its insoluble sedimentation rates increased during warm and dry months and presented significant correlations with meteorological parameters. The highest sedimentation rates were measured at the location with the least permeable surfaces and the lowest green spaces, while the lowest sedimentation rates were found in the sites with abundant green spaces and permeable soil. No significant differences were detected in the soluble components.Our results suggest that SPM levels in Santiago are close to the national limit and may increase with climate change and urban expansion.
Peste des petits ruminants (PPR) in Africa and Asia: A systematic review and meta‐analysis of the prevalence in sheep and goats between 1969 and 2018
Authors: Ahaduzzaman Md 
Published: June 2020

AbstractBackgroundPeste des petits ruminants (PPR) is a prevalent viral disease of sheep and goats that impacts productivity and international animal trade. Despite the substantial economic consequences related to PPR, little is known about the prevalence of this disease at the broad geographical levels.ObjectiveThe present study aimed to use a systematic approach to assess the regional prevalence of PPR in sheep and goats, and the associated factors that contribute to prevalence estimates.MethodsPublished articles on PPR in sheep and goats were searched in PubMed, Web of Science, Scopus, Google Scholar and the reference lists of articles reporting the prevalence from 1 January 1969 to 31 December 2018. Articles were selected using inclusion and exclusion criteria. Since the heterogeneity among the studies was significant, pooled prevalences were estimated by a random effect meta‐analysis model.ResultsData on the prevalence of PPR were obtained from Africa and Asia, where the pooled prevalence estimates were 40.99% (95% CI: 37.20%–44.79%) and 38.43% (95% CI: 35.64%–41.22%) respectively. Overall, the estimated pooled prevalence at Africa‐Asia level in sheep was 39.31% (95% CI: 35.75%–42.88%) and in goats was 39.57% (95% CI: 36.66%–42.48%). Significant heterogeneity (I2 > 80%) was noted in most pooled estimates.ConclusionThe results on the regional prevalence estimates of PPR presented here will be useful in raising awareness and advocating for Governments to engage in initiatives to eradicate PPR and prevent it from spreading to other continents.
Perinatal fluoxetine exposure disrupts the circadian response to a phase-shifting challenge in female rats
Authors: Houwing Danielle J. , de Waard Jolien , Ramsteijn Anouschka S. , Woelders Tom , de Boer Sietse F. , Wams Emma J. , Olivier Jocelien D. A. 
Published: June 2020

Abstract
Rationale
Selective serotonin reuptake inhibitor (SSRI) antidepressants are increasingly prescribed during pregnancy. Changes in serotonergic signaling during human fetal development have been associated with changes in brain development and with changes in affective behavior in adulthood. The suprachiasmatic nucleus (SCN) is known to be modulated by serotonin and it is therefore assumed that SSRIs may affect circadian rhythms. However, effects of perinatal SSRI treatment on circadian system functioning in the offspring are largely unknown.

Objective
Our aim was to investigate the effects of perinatal exposure to the SSRI fluoxetine (FLX) on circadian behavior, affective behavior, and 5-HT1A receptor sensitivity in female rats. In addition, we studied the expression of clock genes and the 5-HT1A receptor in the SCN, as they are potentially involved in underlying mechanisms contributing to changes in circadian rhythms.

Results
Perinatal FLX exposure shortened the free-running tau in response to the 5-HT1A/7 agonist 8-OH-DPAT. However, FLX exposure did not alter anxiety, stress coping, and 5-HT1A receptor sensitivity. No differences were found in 5-HT1A receptor and clock genes Per1, Per2, Cry1, and Cry2 SCN gene expression.

Conclusions
Perinatal FLX exposure altered the response to a phase-shifting challenge in female rats, whether this may pose health risks remains to be investigated.
The Baobab (Adansonia digitata L.) in Southern Kenya–A Study on Status, Distribution, Use and Importance in Taita–Taveta County
Authors: Fischer Sahrah , Jäckering Lisa , Kehlenbeck Katja 
Published: June 2020

AbstractBaobab (Adansonia digitata L.) is a multipurpose, drought resistant, wild fruit tree, endemic to arid and semi-arid lands of Sub-Saharan Africa. Baobab populations have been showing a lack of regeneration, and therefore causes concern for the species survival. This study investigated the state, distribution and use of baobabs in an under-researched population in Kenya, to identify the potential for further use and development of baobab resources. A baobab population was chosen in Taita–Taveta County, covering a sample area of 2015 km2. A systematic stratified transect survey was done to map baobab distribution using 49 transects (0.5 × 3 km each). The diameter at breast height and other indicators were measured on all baobabs in the transects to assess population status and health. A household survey (n = 46) and focus group discussions (n = 12) were done following the transect survey to gain an idea on the uses and distribution of baobab. In total, 432 baobab trees were measured and recorded in the research area of 2015 km2. The baobabs grew in two clusters (i.e., areas with a baobab density of ≥0.08 baobabs/ha). Both clusters showed rejuvenating populations. The main factors identified by the respondents, positively and negatively influencing baobab distribution were environmental factors, wildlife, human impact and commercial value. The study area shows a great potential for baobab to become an important part of the diet, due to its current use as an emergency food during food scarce times, and the relatively healthy and stable rejuvenating populations.
A novel multi-fidelity modelling-based framework for reliability-based design optimisation of composite structures
Authors: Yoo Kwangkyu , Bacarreza Omar , Aliabadi M. H. Ferri 
Published: June 2020

AbstractA new multi-fidelity modelling-based probabilistic optimisation framework for composite structures is presented in this paper. The multi-fidelity formulation developed herein significantly reduces the required computational time, allowing for more design variables to be considered early in the design stage. Multi-fidelity models are created by the use of finite element models, surrogate models and response correction surfaces. The accuracy and computational efficiency of the proposed optimisation methodology are demonstrated in two engineering examples of composite structures: a reliability analysis, and a reliability-based design optimisation. In these two benchmark examples, each random design variable is assigned an expected level of uncertainty. Monte Carlo Simulation (MCS), the First-Order Reliability Method (FORM) and the Second-Order Reliability Method (SORM) are used within the multi-fidelity framework to calculate the probability of failure. The reliability optimisation is a multi-objective problem that finds the optimal front, which provides both the maximum linear buckling load and minimum mass. The results show that multi-fidelity models provide high levels of accuracy while reducing computation time drastically.