bluuebunny/crossref_metadata_2025_split huggingface dataset:
Biopolymer nanocomposite blends of poly(lactic acid) and polyhydroxybutyrate biopolymers reinforced with cellulose nanofibrils at low loading ratio
Authors: Aydemir Deniz , Gumus Havva , Altuntas Ertugrul , Yalçın Ömer Ümit , Özan Zeynep Eda 
Published: July 2024

AbstractThis study investigated the mechanical, morphological, thermal, rheological properties, and accelerated aging performance of poly(lactic acid) (PLA)/polyhydroxybutyrate (PHB) blends with cellulose nanofibrils (CNFs) at low loading ratio. According to the obtained results, the addition of both PLA and CNFs were found to generally increase the mechanical properties of the biopolymer nanocomposites (BNCs). Morphological characterization with scanning electron microscopy (SEM) exhibited that cellular structure occurred in all the BNCs with adding both PLA and CNFs. Thermal stability of the BNCs improved with PLA and CNFs. The addition of CNFs and PLA generally increased the isotherms including Tg, Tc, and Tm according to differential scanning calorimetry (DSC), and it was found that the blends' crystallinity dropped because of a poor crystallinity of PLA. The addition of both PLA and CNFs provided an improvement on the rheological and viscoelastic properties of the neat PHB. XRD pattern of all the BNCs was found to be similar to the neat blends and the BNCs. In the accelerated weathering test, the adding PLA to neat PHB was found to provide more improvement than adding of CNFs.
Delamination bridging response of Z‐pins under mixed mode loading: The influence of carbon and Kevlar Z‐pins
Authors: Gong Bowen , Liao Yijian , Ge Yuzhong , Ouyang Wenting , Wang Huan , Nartey Martinson , Gao Xiang , Peng Hua‐Xin 
Published: July 2024

AbstractThis paper presents the effect of varying the type of Z‐pin on the delamination bridging performance of unidirectional composite laminates. Carbon and Kevlar Z‐pins were inserted in thick composite laminates using the pre‐hole insertion Z‐pinning process and their bridging performance characterized across the different mode‐mixity range. The bridging response indicated that Kevlar Z‐pin experienced load reduction driven by interfacial friction (Stage III), which was absent in the Carbon Z‐pin. When Mode II dominated the bridging crack, Kevlar Z‐pin showed partial pullout and fiber shear cracking, while the Carbon Z‐pin exhibited clean transverse fracture. Although the bridging load obtained by the Carbon Z‐pin was twice that of Kevlar Z‐pin, the Kevlar Z‐pin provided a higher interlaminar fracture energy. The superior bridging performance of Kevlar Z‐pin is correlated with the enhanced ductility. Moreover, the resin‐rich area was involved in deformation and provided the extra axial load of Z‐pin.Highlights
The comparison of mixed‐mode bridging mechanism between Kevlar Z‐pin and Carbon Z‐pin.
Reveal the variation of multi‐directional load and energy consumption with mixed‐mode angle in thick laminates.
Detailed scanning electron microscope observation to understand failure characteristics of ductile Z‐pin.
Evidence that the extra axial load of Z‐pin provided by resin‐rich area.
Tuning thermal and structural properties of nano‐filled PDMS elastomer
Authors: Mandal Swaroop Kumar , Kumar Rahul , Rizwee Mumtaz , Kumar Deepak 
Published: July 2024

AbstractIncreasing the thermal stability and thermal conductivity of polydimethylsiloxane (PDMS) is a crucial issue for thermal applications. This paper focuses on enhancing PDMS's thermal and structural properties by incorporating nanocomposite into the PDMS matrix. An investigation of the impact of rGO‐CaCO3 nanocomposite on the thermal and structural properties of PDMS was performed using Field Emission Scanning Electron Microscopy (FESEM), X‐ray diffraction (XRD), the thermogravimetric analysis and differential thermal analysis (TGA‐DTA), and thermal analyzer tests. It was observed that PDMS doped with rGO‐CaCO3 nanocomposite shows better thermal stability, thermal conductivity, and higher crystallinity. The thermal stability was enhanced significantly by adding a 5% rGO‐CaCO3 nanocomposite, and the initial and end degradation temperatures rose to 492°C and 605°C, respectively. The thermal conductivity of pure PDMS is approximately 0.17 W/mK, whereas a conductive elastomer filled with 5% rGO‐CaCO3 nanocomposite exhibits a thermal conductivity of 0.44 W/mK at a temperature of 20°C. In contrast, the thermal diffusivity is enhanced from 0.13 mm2/s to 0.366 mm2/s. Additionally, the Fourier Transform Infra‐Red (FTIR) spectrum at 1411 cm−1 becomes sharp and noisy, and an additional peak arises at 1398 cm−1, corresponding to the vibrational rocking of the CC bond and COC bond in CaCO3 and rGO.Highlights
The manuscript focuses on the development of conductive elastomer by incorporating rGO‐CaCO3 doped and its effect on the morphology, structure, and thermal properties of PDMS.
The variation in peak intensity observed in XRD attributed to disparities in the crystalline structure of PDMS due to the inclusion of nanocomposite.
The thermal degradation range is observed to shift toward the upper end. The degradation temperature at the beginning and end of the process is observed to move to 492°C and 605°C, respectively, upon introducing a 5% rGO‐CaCO3 nanocomposite.
The addition of 5% rGO‐CaCO3 filled conductive elastomers shows a significant improvement of approximately 2.6 times in heat conductivity than bare PDMS.
Analysis of the effect of boric acid and compatibilizer addition to polylactic acid/basalt fiber composites
Authors: Dincer Ugur , Karsli Nevin Gamze , Sahin Tulin , Yilmaz Taner 
Published: July 2024

AbstractThe objective of this study is to improve the properties of polylactic acid (PLA), a biopolymer produced from renewable resources, without compromising its environmentally friendly “natural composite” properties. The aim was to expand the application range of PLA by making it suitable for the production of high performance composites. With this in mind, it was decided to use inorganic and environmentally friendly materials such as basalt fiber (BF) and boric acid (BA) as reinforcements. Adhesive wear and tensile tests were used to investigate the tribological and mechanical performance of the composites. Differential scanning calorimetry (DSC) and dimensional stability analysis (DSA) methods were used to investigate the thermal properties. Scanning electron microscopy analysis was also used to investigate the morphological properties of the samples. In addition, a matrix modification process using Joncryl®, an epoxy‐based chain extender chemical, was applied to enhance the interfacial interaction between the composite components and improve the composite properties by improving the dispersion of reinforcing materials. As a result of the characterization tests, it was observed that a significant improvement in the properties of the material type containing 10 wt% BF, 0.25 wt% BA and 2 wt% Joncryl® was achieved. A 19% increase in tensile strength of this type of material was observed compared with unreinforced PLA, while the sharp peak increase in the coefficient of friction (COF) curve was shifted from 20 m to 60 m. As a result, it has been presented that environmentally friendly and inorganic materials such as BF and BA can be used to produce composite materials that will serve sectors where the need and use of high performance materials is intense, especially in the automotive, aerospace and aviation sectors.Highlights
The properties of PLA matrix composites were improved by the simultaneous use of BF and BA and the addition of Joncryl®.
The structural properties of PLA, an environmentally friendly polymer, have been improved without compromising this characteristic.
PLA matrix natural composites with performance that can be used in the automotive, aerospace and aviation sectors have been developed.
Optimization‐Based Stable Balancing Weights Versus Propensity Score Weighting for Samples With High Covariate Imbalance
Authors: Wallace Stuart R. , Singh Sachinkumar B. , Blakney Rebekah , Rene Lexi , Johnston Stephen S. 
Published: July 2024

ABSTRACTPurposeTo compare the performance (covariate balance, effective sample size [ESS]) of stable balancing weights (SBW) versus propensity score weighting (PSW). Two applied cases were used to compare performance: (Case 1) extreme imbalance in baseline covariates between groups and (Case 2) substantial discrepancy in sample size between groups.MethodsUsing the Premier Healthcare Database, we selected patients who (Case 1) underwent a surgical procedure with one of two different bipolar forceps between January 2000 and June 2020, or (Case 2) a neurological procedure using one of two different nonabsorbable surgical sutures between January 2000 and March 2020. Average treatment effects on the treated (ATT) weights were generated based on selected covariates. SBW was implemented using two techniques: (1) “grid search” to find weights of minimum variance at the lowest target absolute standardized mean difference (SMD); (2) finding weights of minimum variance at prespecified SMD tolerance. PSW and SBW methods were compared on postweighting SMDs, the number of imbalanced covariates, and ESS of the ATT‐weighted control group.ResultsIn both studies, improved covariate balance was achieved with both SBW techniques. All methods suffered from postweighting ESS that was lower than the unweighted control group's original sample size; however, SBW methods achieved higher ESS for the control groups. Sensitivity analyses using SBW to apply variable‐specific SMD thresholds increased ESS, outperforming PSW.ConclusionsIn this applied example, the optimization‐based SBW method provided ample flexibility with respect to prespecification of covariate balance goals and resulted in better postweighting covariate balance and larger ESS as compared with PSW.
Preparation and characterization of pyrimidine‐cored covalent organic frameworks for heavy metal removal
Authors: Wang Heping , Ma Qian , Wang Yunxia , Li Rui , Fu Jiahuan , Bai Qiuhong 
Published: July 2024

AbstractIn this work, two novel pyrimidine‐cored covalent organic frameworks TpTap‐COF and TpTan‐COF were synthesized for the first time and used for the adsorption of heavy metal ions in aqueous solution. Both COFs are nanofiber clusters with preferable crystallinity and thermal stability. The impact parameters such as pH value, shaking time, initial concentration, and temperature were studied by batch adsorption experiments in the multi‐metal ions system. The adsorption of six metal ions onto COFs follows the pseudo‐second‐order kinetic model and the Freundlich isotherm model, which is a chemical adsorption process that occurs on non‐uniform surfaces. The adsorption rate is determined by both film diffusion and intraparticle diffusion. Further research on the adsorption of copper ions onto COFs indicates the formation of metal complexes between O#N#N/O#O chelating sites in the COF skeleton and Cu ions through the sharing of lone pair electrons.
Across Madagascar, treeless grasslands characterised by erosion gullies are named after forest and trees
Authors: Joseph Grant S. , Randriatsara Fetraharimalala , Rakotoarivelo Andrinajoro R. , Rafidiarimanda Ando A. , Seymour Colleen L. 
Published: July 2024

Societal Impact StatementDebates about the impacts of human settlement on Madagascar's habitat have missed the Malagasy perspective. Using indigenous and local knowledge in the form of toponyms, we find many regions across today's treeless grasslands are named after forest/trees, suggesting they may be novel. Where observed habitat does not match toponyms, erosion is significantly more likely at landscape scales. This suggests rapid expansion of erosion following human removal and burning of endemic forest, savanna woodland, heathland and grass assemblages. Findings also provide a timely warning: current practices may be unsustainable and may impact not only biodiversity but also human wellbeing unless urgently addressed.SummaryThe debate surrounding the extent of Madagascar's treeless grasslands at human settlement is important because introduced disturbance can negatively impact the biodiversity and productivity of systems that evolved under different regimes. Indigenous and local knowledge (ILK), often overlooked, can provide information about past vegetation structure. To test whether clearance of forest and trees, frequent fires and pasture preparation have accelerated today's island‐wide erosion, we use vegetation toponyms and assess whether mismatches between these and current vegetation types are significantly more likely to be associated with erosion.Using Malagasy and Imerina linguistic records spanning 150 years, we mapped forest‐related and grassland‐related extensive toponyms in current grassland and forest, respectively. We then assessed whether remotely‐sensed erosion was more likely when toponyms and current habitat did not match.We found 316 sites in treeless grasslands, named after forest/clusters of trees, but no grassland‐named sites in forest. Globally, natural forest and grasslands both constrain erosion. Forest toponyms in grassland were significantly more likely to reflect erosion than sites in extant forest.These findings concur with palaeoecological, geomorphological, molecular and rangeland palatability studies. Malagasy ILK, hitherto largely ignored as a source of information, strongly suggests vegetation clearance and human disturbance have exacerbated the degradation of terrestrial, freshwater and marine ecosystems through topsoil loss and siltation and selected fire‐adapted, less‐palatable grasslands. Malagasy ILK in the form of toponyms highlights the need to address the negative impacts of burning and land‐clearance practices (e.g., loss of biodiversity and ecological function, decreased agricultural productivity, collapsed fisheries), given island‐wide challenges to food security and conservation.
miRNA and leptin signaling in metabolic diseases and at extreme environments
Authors: Mondal Samrita , Rathor Richa , Singh Som Nath , Suryakumar Geetha 
Published: July 2024

AbstractThe burden of growing concern about the dysregulation of metabolic processes arises due to complex interplay between environment and nutrition that has great impact on genetics and epigenetics of an individual. Thereby, any abnormality at the level of food intake regulating hormones may contribute to the development of metabolic diseases in any age group due to malnutrition, overweight, changing lifestyle, and exposure to extreme environments such as heat stress (HS), cold stress, or high altitude (HA). Hormones such as leptin, adiponectin, ghrelin, and cholecystokinin regulate appetite and satiety to maintain energy homeostasis. Leptin, an adipokine and a pleiotropic hormone, play major role in regulating the food intake, energy gain and energy expenditure. Using in silico approach, we have identified the major genes (LEP, LEPR, JAK2, STAT3, NPY, POMC, IRS1, SOCS3) that play crucial role in leptin signaling pathway. Further, eight miRNAs (hsa‐miR‐204‐5p, hsa‐miR‐211‐5p, hsa‐miR‐30, hsa‐miR‐3163, hsa‐miR‐33a‐3p, hsa‐miR‐548, hsa‐miR‐561‐3p, hsa‐miR‐7856‐5p) from TargetScan 8.0 database were screened out that commonly target these genes. The role of these miRNAs should be explored as they might play vital role in regulating the appetite, energy metabolism, metabolic diseases (obesity, type 2 diabetes, cardiovascular diseases, inflammation), and to combat extreme environments. The miRNAs regulating leptin signaling and appetite may be useful for developing novel therapeutics for metabolic diseases.
Energy drink consumption among Israeli‐Arab adolescents: Gender differences in anxiety and well‐being
Authors: Nimri Lili , Mansour Bshara , Benhos Amir , Banna Abdallah , Nasrallah Elias , Sackran Marwan , Ahmad Ahlam Abu , Ardi Ziv , Horovitz Omer 
Published: July 2024

AbstractBackgroundIsraeli‐Arab adolescents are reported to consume higher amounts of fast food, sweets, and candies. This study examined possible associations among energy drink consumption, anxiety, and well‐being in Israeli‐Arab adolescents. We also investigated these associations concerning fast food consumption, physical activity, and hours of sleep per night.MethodsA cross‐sectional exploratory study assessed adolescents’ energy drink consumption, nutritional and lifestyle habits, well‐being, and anxiety using self‐reported questionnaires. Adolescents aged 12–18 from several cities and villages in northern Israel were considered for the study. Anthropometric measurements—weight, height, and waist circumference—were also assessed.ResultsOne hundred and fourteen adolescents (59 females) participated in the study. Gender and energy drink consumption were associated with psychological status. Energy drink consumers reported a lower well‐being index and a higher anxiety index than nonconsumers (73.02 ± 2.64 and 23 ± 1.56 vs. 79.37 ± 1.67 and 18.86 ± 1.41, respectively). Energy drink consumers ate significantly more fast food per week than nonconsumers (1.25 ± 0.07 vs. 1.03 ± 0.09). Additionally, hours of sleep per night were correlated with anxiety levels among energy drink consumers [rs = 0.352, p = 0.018]. These results differed between genders.ConclusionsOur study shows complex associations between energy drink consumption and mental health indices. These associations can serve as a basis for further research into this topic.
Water penetrating radar: A fluvial scour study of antenna performance and data processing
Authors: Ruffell Alastair , O'Keefe Amy , Campbell Kris , Lydon Myra 
Published: July 2024

AbstractGround‐penetrating radar (syn. water‐penetrating radar, or WPR hereon) has been used previously in the detection and characterisation of riverine scour. This paper presents field data, equipment calibration and processing output results from a new generation of high dynamic range (HDR) radar systems. These provide a new and more sophisticated model of fluvial scour for the study site. The adaptability for deployment on water, wide bandwidth and good quality in raw and processed data, demonstrates the advantages of the system. Data processing and depth calibration are issues in the interpretation of WPR data, which are both discussed. WPR demonstrates the potential for surveying sedimentation where palaeoscour occurred and thus anticipated. This maybe in conjunction with other techniques or where aquatic vegetation, rocky substrates or methane gas bubble release preclude use of sonar.
Towards Implantable Artificial Muscles: Epoxy Based Bilayer Thermal Actuators with Ambient Activation Temperatures
Authors: Baker Benjamin C. , Kershaw Leo , Yang Ziqui , Garrad Martin , Faul Charl F. J. 
Published: July 2024

AbstractThe development of soft and biocompatible actuators is a current challenge in the fast‐growing field of soft robotics. A variety of shape‐memory and thermal actuators are currently being explored for application in these areas, especially to produce actuators that can operate at biocompatible temperatures for in vivo applications. Here we detail the synthesis of epoxy based materials, a class of materials not fully explored for soft actuators. By careful tuning of polymer composition by variation of monomer feed ratios, we show tuneable glass transition temperatures (Tgs) of these materials. Ambient temperature (30–60 °C) thermal actuators were then realised by casting of bilayers of epoxy resins with varying Tgs. Differences in thermal expansion when the Tg was reached lead to actuation in a specific direction. With optimisation, actuation in both the external‐heated and joule‐heated NiChrome‐epoxy actuators were able to occur at physiological temperatures (36–40 °C), previously unreported in the literature. For the joule‐heated NiChrome–epoxy actuators surface temperatures remained under 40 °C during actuation at low operating voltages (<2 V). Higher force and power output could be achieved in a repeatable fashion at higher driving voltages without loss of displacement, but also leading to higher surface temperatures. These materials and the actuation approach present an exciting opportunity to develop future implantable actuators to solve significant challenges related to quality of life and an ageing population.
[MTP−IL] as Mesoporous Heterogeneous Organocatalyst for the One‐Pot Synthesis of Indeno [1,2‐b] Quinoxalin‐11‐Ylidenamine Derivatives: A Green, Sustainable, and Metal‐Free Protocol
Authors: Mustafa Atif , Zameer Nazia , Khan Nida , Siddiqui Zeba N. 
Published: July 2024

AbstractHerein, we report a green, sustainable, and metal‐free, one‐pot three‐component protocol for the synthesis of indeno [1, 2‐b] quinoxalin‐11‐ylidenamine derivatives using a novel, effective, and recyclable mesoporous heterogeneous organocatalyst [MTP−IL]. [MTP−IL] was constructed by immobilizing an imidazolium‐cation‐based ionic liquid on a melamine−terephthalaldehyde covalent organic polymer and was thoroughly characterized using several analytical techniques. It displayed high thermochemical stability and catalytic efficacy, offering title compounds with 90–94 % yields in a short reaction time, and was recyclable for up to six cycles. The synthesized compounds were characterized through FTIR, 1H, and 13C Nuclear Magnetic Resonance (NMR), and the molecular structure of N′‐(11H‐indeno[1,2‐b]quinoxalin‐11‐ylidene)benzohydrazide (7) was confirmed by the Single Crystal XRD (SCXRD) analysis. The key features of the present protocol are the use of ethanol as a green solvent, easy catalyst recovery, a simple work‐up procedure, and zero involvement of any metal.
Enhanced Physio‐Chemical Properties of PMMA/PS Polymer Blends by DC Glow Discharge Plasma Treated K2TI6O13for Electronic Applications
Authors: Humbe Shankar S. , Joshi Girish M. , Deshmukh R. R. 
Published: July 2024

AbstractCeramic filler modified polymer blends are more in demand due to their excellent compatibility, easy processing and cost‐effectiveness. In the present work, we modified Polymethyl methacrylate (PMMA)/Polystyrene (PS) blends using solution blending with untreated (UT) and DC glow discharge plasma‐treated (air plasma treated‐APT) potassium hexatitanate (K2Ti6O13). Chemical bonding of virgin and modified blends was confirmed by Fourier transform infrared spectrophotometer (FTIR). Decreased structural defects and imperfections of KTO were confirmed by Raman spectroscopy. Modified surface morphology and elemental analysis were detected by scanning electron microscopy (SEM) and energy‐dispersive X‐ray analysis (EDAX). The quantification of particle size distribution has been determined by Zetasizer. Increased degree of crystallinity and decreased average crystallite size after plasma treatment were determined by X‐ray diffraction. Increased dielectric constant from ~22–200 and decreased loss up to 0.7 were analyzed by impedance analyzer. Lee's disc probe was deployed to confirm the optimized thermal conductivity of the modified blend system. By Differential Scanning Calorimetry, glass transition temperature of modified polymer blends was investigated. The change in surface from hydrophobic to hydrophilic by plasma exposure was confirmed by surface goniometer. However, the enhanced dielectric performance of modified PMMA/PS/KTO polymer blends may be suitable for flexible energy storage devices and gadgets.