bluuebunny/crossref_metadata_2025 huggingface dataset:
The Degradation of Botulinum Neurotoxin Light Chains Using PROTACs
Authors: Tsai Yien Che , Kozar Loren , Mawi Zo P. , Ichtchenko Konstantin , Shoemaker Charles B. , McNutt Patrick M. , Weissman Allan M.
Published: July 2024

Botulinum neurotoxins are some of the most potent natural toxins known; they cause flaccid paralysis by inhibiting synaptic vesicle release. Some serotypes, notably serotype A and B, can cause persistent paralysis lasting for several months. Because of their potency and persistence, botulinum neurotoxins are now used to manage several clinical conditions, and there is interest in expanding their clinical applications using engineered toxins with novel substrate specificities. It will also be beneficial to engineer toxins with tunable persistence. We have investigated the potential use of small-molecule proteolysis-targeting chimeras (PROTACs) to vary the persistence of modified recombinant botulinum neurotoxins. We also describe a complementary approach that has potential relevance for botulism treatment. This second approach uses a camelid heavy chain antibody directed against botulinum neurotoxin that is modified to bind the PROTAC. These strategies provide proof of principle for the use of two different approaches to fine tune the persistence of botulinum neurotoxins by selectively targeting their catalytic light chains for proteasomal degradation.
Genome-Wide Analysis of the Auxin/Indoleacetic Acid (Aux/IAA) Gene Family in Autopolyploid Sugarcane (Saccharum spontaneum)
Authors: Huang Xiaojin , Shad Munsif Ali , Shu Yazhou , Nong Sikun , Li Xianlong , Wu Songguo , Yang Juan , Rao Muhammad Junaid , Aslam Muhammad Zeshan , Huang Xiaoti , Huang Dige , Wang Lingqiang
Published: July 2024

The auxin/indoleacetic acid (Aux/IAA) family plays a central role in regulating gene expression during auxin signal transduction. Nonetheless, there is limited knowledge regarding this gene family in sugarcane. In this study, 92 members of the IAA family were identified in Saccharum spontaneum, distributed on 32 chromosomes, and classified into three clusters based on phylogeny and motif compositions. Segmental duplication and recombination events contributed largely to the expansion of this superfamily. Additionally, cis-acting elements in the promoters of SsIAAs involved in plant hormone regulation and stress responsiveness were predicted. Transcriptomics data revealed that most SsIAA expressions were significantly higher in stems and basal parts of leaves, and at nighttime, suggesting that these genes might be involved in sugar transport. QRT-PCR assays confirmed that cold and salt stress significantly induced four and five SsIAAs, respectively. GFP-subcellular localization showed that SsIAA23 and SsIAA12a were localized in the nucleus, consistent with the results of bioinformatics analysis. In conclusion, to a certain extent, the functional redundancy of family members caused by the expansion of the sugarcane IAA gene family is related to stress resistance and regeneration of sugarcane as a perennial crop. This study reveals the gene evolution and function of the SsIAA gene family in sugarcane, laying the foundation for further research on its mode of action.
HER4 Affects Sensitivity to Tamoxifen and Abemaciclib in Luminal Breast Cancer Cells and Restricts Tumor Growth in MCF-7-Based Humanized Tumor Mice
Authors: Albert Veruschka , Bruss Christina , Tümen Deniz , Piendl Gerhard , Weber Florian , Dahl Edgar , Seitz Stephan , Ortmann Olaf , Wege Anja K. , Brockhoff Gero
Published: July 2024

The impact of the HER4 receptor on the growth and treatment of estrogen receptor-positive breast cancer is widely uncertain. Using CRISPR/Cas9 technology, we generated stable HER4 knockout variants derived from the HER4-positive MCF-7, T-47D, and ZR-75-1 breast cancer cell lines. We investigated tumor cell proliferation as well as the cellular and molecular mechanisms of tamoxifen, abemaciclib, AMG232, and NRG1 treatments as a function of HER4 in vitro. HER4 differentially affects the cellular response to tamoxifen and abemaciclib treatment. Most conspicuous is the increased sensitivity of MCF-7 in vitro upon HER4 knockout and the inhibition of cell proliferation by NRG1. Additionally, we assessed tumor growth and immunological effects as responses to tamoxifen and abemaciclib therapy in humanized tumor mice (HTM) based on MCF-7 HER4-wildtype and the corresponding HER4-knockout cells. Without any treatment, the enhanced MCF-7 tumor growth in HTM upon HER4 knockout suggests a tumor-suppressive effect of HER4 under preclinical but human-like conditions. This phenomenon is associated with an increased HER2 expression in MCF-7 in vivo. Independent of HER4, abemaciclib and tamoxifen treatment considerably inhibited tumor growth in these mice. However, abemaciclib-treated hormone receptor-positive breast cancer patients with tumor-associated mdm2 gene copy gains or pronounced HER4 expression showed a reduced event-free survival. Evidently, the presence of HER4 affects the efficacy of tamoxifen and abemaciclib treatment in different estrogen receptor-positive breast cancer cells, even to different extents, and is associated with unfavorable outcomes in abemaciclib-treated patients.
Role of Oxidative Stress and Inflammation in Doxorubicin-Induced Cardiotoxicity: A Brief Account
Authors: Vitale Roberta , Marzocco Stefania , Popolo Ada
Published: July 2024

Cardiotoxicity is the main side effect of several chemotherapeutic drugs. Doxorubicin (Doxo) is one of the most used anthracyclines in the treatment of many tumors, but the development of acute and chronic cardiotoxicity limits its clinical usefulness. Different studies focused only on the effects of long-term Doxo administration, but recent data show that cardiomyocyte damage is an early event induced by Doxo after a single administration that can be followed by progressive functional decline, leading to overt heart failure. The knowledge of molecular mechanisms involved in the early stage of Doxo-induced cardiotoxicity is of paramount importance to treating and/or preventing it. This review aims to illustrate several mechanisms thought to underlie Doxo-induced cardiotoxicity, such as oxidative and nitrosative stress, inflammation, and mitochondrial dysfunction. Moreover, here we report data from both in vitro and in vivo studies indicating new therapeutic strategies to prevent Doxo-induced cardiotoxicity.
DNA Methylation of the Autonomous Pathway Is Associated with Flowering Time Variations in Arabidopsis thaliana
Authors: Xie Hongjie , Li Xinchen , Sun Yuli , Lin Lei , Xu Keke , Lu Huan , Cheng Biao , Xue Siming , Cheng Dan , Qiang Sheng
Published: July 2024

Plant flowering time is affected by endogenous and exogenous factors, but its variation patterns among different populations of a species has not been fully established. In this study, 27 Arabidopsis thaliana accessions were used to investigate the relationship between autonomous pathway gene methylation, gene expression and flowering time variation. DNA methylation analysis, RT-qPCR and transgenic verification showed that variation in the flowering time among the Arabidopsis populations ranged from 19 to 55 days and was significantly correlated with methylation of the coding regions of six upstream genes in the autonomous pathway, FLOWERING LOCUS VE (FVE), FLOWERING LOCUS Y (FY), FLOWERING LOCUS D (FLD), PEPPER (PEP), HISTONE DEACETYLASE 5 (HAD5) and Pre-mRNA Processing Protein 39-1 (PRP39-1), as well as their relative expression levels. The expression of FVE and FVE(CS) was modified separately through degenerate codon substitution of cytosine and led to earlier flowering of transgenic plants by 8 days and 25 days, respectively. An accurate determination of methylated sites in FVE and FVE(CS) among those transgenic plants and the recipient Col-0 verified the close relationship between the number of methylation sites, expression and flowering time. Our findings suggest that the methylation variation of these six key upstream transcription factors was associated with the gene expression level of the autonomous pathway and flowering time in Arabidopsis. The FVE(CS) and FVE genes in transgenic plants tended to be hypermethylated, which could be a protective mechanism for plants. However, modification of gene sequences through degenerate codon substitution to reduce cytosine can avoid hypermethylated transferred genes in transgenic plants. It may be possible to partially regulate the flowering of plants by modified trans-epigenetic technology.
Association between Visceral Adipose Tissue Metabolism and Cerebral Glucose Metabolism in Patients with Cognitive Impairment
Authors: Yu Mi-Hee , Lim Ji Sun , Yi Hyon-Ah , Won Kyoung Sook , Kim Hae Won
Published: July 2024

Visceral adipose tissue (VAT) dysfunction has been recently recognized as a potential contributor to the development of Alzheimer’s disease (AD). This study aimed to explore the relationship between VAT metabolism and cerebral glucose metabolism in patients with cognitive impairment. This cross-sectional prospective study included 54 patients who underwent 18F-fluorodeoxyglucose (18F-FDG) brain and torso positron emission tomography/computed tomography (PET/CT), and neuropsychological evaluations. VAT metabolism was measured by 18F-FDG torso PET/CT, and cerebral glucose metabolism was measured using 18F-FDG brain PET/CT. A voxel-based analysis revealed that the high-VAT-metabolism group exhibited a significantly lower cerebral glucose metabolism in AD-signature regions such as the parietal and temporal cortices. In the volume-of-interest analysis, multiple linear regression analyses with adjustment for age, sex, and white matter hyperintensity volume revealed that VAT metabolism was negatively associated with cerebral glucose metabolism in AD-signature regions. In addition, higher VAT metabolism was correlated with poorer outcomes on cognitive assessments, including the Korean Boston Naming Test, Rey Complex Figure Test immediate recall, and the Controlled Oral Word Association Test. In conclusion, our study revealed significant relationships among VAT metabolism, cerebral glucose metabolism, and cognitive function. This suggests that VAT dysfunction actively contributes to the neurodegenerative processes characteristic of AD, making VAT dysfunction targeting a novel AD therapy approach.
Altered Inflammatory State and Mitochondrial Function Identified by Transcriptomics in Paediatric Congenital Heart Patients Prior to Surgical Repair
Authors: Bartoli-Leonard Francesca , Harris Amy G. , Saunders Kelly , Madden Julie , Cherrington Carrie , Sheehan Karen , Baquedano Mai , Parolari Giulia , Bamber Andrew , Caputo Massimo
Published: July 2024

Congenital heart disease (CHD) remains the most common birth defect, with surgical intervention required in complex cases. Right ventricle (RV) function is known to be a major predictor of sustained cardiac health in these patients; thus, by elucidating the divergent profiles between CHD and the control through tissue analysis, this study aims to identify new avenues of investigation into the mechanisms surrounding reduced RV function. Transcriptomic profiling, in-silico deconvolution and functional network analysis were conducted on RV biopsies, identifying an increase in the mitochondrial dysfunction genes RPPH1 and RMPR (padj = 4.67 × 10−132, 2.23 × 10−107), the cytotoxic T-cell markers CD8a, LAGE3 and CD49a (p = 0.0006, p < 0.0001, and p = 0.0118) and proinflammatory caspase-1 (p = 0.0055) in CHD. Gene-set enrichment identified mitochondrial dysfunctional pathways, predominately changes within oxidative phosphorylation processes. The negative regulation of mitochondrial functions and metabolism was identified in the network analysis, with dysregulation of the mitochondrial complex formation. A histological analysis confirmed an increase in cellular bodies in the CHD RV tissue and positive staining for both CD45 and CD8, which was absent in the control. The deconvolution of bulk RNAseq data suggests a reduction in CD4+ T cells (p = 0.0067) and an increase in CD8+ T cells (p = 0.0223). The network analysis identified positive regulation of the immune system and cytokine signalling clusters in the inflammation functional network, as there were lymphocyte activation and leukocyte differentiation. Utilising RV tissue from paediatric patients undergoing CHD cardiac surgery, this study identifies dysfunctional mitochondrial pathways and an increase in inflammatory T-cell presence prior to reparative surgery.
Chalcogen Noncovalent Interactions between Diazines and Sulfur Oxides in Supramolecular Circular Chains
Authors: Rahali Emna , Noori Zahra , Arfaoui Youssef , Poater Jordi
Published: July 2024

The noncovalent chalcogen interaction between SO2/SO3 and diazines was studied through a dispersion-corrected DFT Kohn–Sham molecular orbital together with quantitative energy decomposition analyses. For this, supramolecular circular chains of up to 12 molecules were built with the aim of checking the capability of diazine molecules to detect SO2/SO3 compounds within the atmosphere. Trends in the interaction energies with the increasing number of molecules are mainly determined by the Pauli steric repulsion involved in these σ-hole/π-hole interactions. But more importantly, despite the assumed electrostatic nature of the involved interactions, the covalent component also plays a determinant role in its strength in the involved chalcogen bonds. Noticeably, π-hole interactions are supported by the charge transfer from diazines to SO2/SO3 molecules. Interaction energies in these supramolecular complexes are not only determined by the S···N bond lengths but attractive electrostatic and orbital interactions also determine the trends. These results should allow us to establish the fundamental characteristics of chalcogen bonding based on its strength and nature, which is of relevance for the capture of sulfur oxides.
TLR Agonists Modify NK Cell Activation and Increase Its Cytotoxicity in Acute Lymphoblastic Leukemia
Authors: Gallardo-Zapata Janet , Pérez-Figueroa Erandi , Olivar-López Víctor , Medina-Sansón Aurora , Jiménez-Hernández Elva , Ortega Enrique , Maldonado-Bernal Carmen
Published: July 2024

Natural killer (NK) cells play a crucial role in innate immunity, particularly in combating infections and tumors. However, in hematological cancers, NK cells often exhibit impaired functions. Therefore, it is very important to activate its endosomal Toll-like receptors (TLRs) as a potential strategy to restore its antitumor activity. We stimulated NK cells from the peripheral blood mononuclear cells from children with acute lymphoblastic leukemia and NK cells isolated, and the NK cells were stimulated with specific TLR ligands (Poly I:C, Imiquimod, R848, and ODN2006) and we evaluated changes in IFN-γ, CD107a, NKG2D, NKp44 expression, Granzyme B secretion, cytokine/chemokine release, and cytotoxic activity. Results revealed that Poly I:C and Imiquimod enhanced the activation of both immunoregulatory and cytotoxic NK cells, increasing IFN-γ, CD107a, NKG2D, and NKp44 expression. R848 activated immunoregulatory NK cells, while ODN2006 boosted CD107a, NKp44, NKG2D, and IFN-γ secretion in cytotoxic NK cells. R848 also increased the secretion of seven cytokines/chemokines. Importantly, R848 and ODN 2006 significantly improved cytotoxicity against leukemic cells. Overall, TLR stimulation enhances NK cell activation, suggesting TLR8 (R848) and TLR9 (ODN 2006) ligands as promising candidates for antitumor immunotherapy.
Current Advances in Nanomaterials Affecting Functions and Morphology of Platelets
Authors: Peng Dongxin , Sun Sujing , Zhao Man , Zhan Linsheng , Wang Xiaohui
Published: July 2024

Nanomaterials have been extensively used in the biomedical field due to their unique physical and chemical properties. They promise wide applications in the diagnosis, prevention, and treatment of diseases. Nanodrugs are generally transported to target tissues or organs by coupling targeting molecules or enhanced permeability and retention effect (EPR) passively. As intravenous injection is the most common means of administration of nanomedicine, the transport process inevitably involves the interactions between nanoparticles (NPs) and blood cells. Platelets are known to not only play a critical role in normal coagulation by performing adhesion, aggregation, release, and contraction functions, but also be associated with pathological thrombosis, tumor metastasis, inflammation, and immune reactions, making it necessary to investigate the effects of NPs on platelet function during transport, particularly the way in which their physical and chemical properties determine their interaction with platelets and the underlying mechanisms by which they activate and induce platelet aggregation. However, such data are lacking. This review is intended to summarize the effects of NPs on platelet activation, aggregation, release, and apoptosis, as well as their effects on membrane proteins and morphology in order to shed light on such key issues as how to reduce their adverse reactions in the blood system, which should be taken into consideration in NP engineering.
0.35 V Subthreshold Bulk-Driven CMOS Second-Generation Current Conveyor
Authors: Shah Muhammad Omer , Caruso Manfredi , Pennisi Salvatore
Published: July 2024

This study describes a high-performance second-generation Current Conveyor (CCII) operating at 0.35 V and achieving rail-to-rail operation at the Y terminal and class AB current drive at the X and Z terminals. The solution utilizes a low-voltage subthreshold bulk-driven CMOS OTA that was experimentally developed earlier, making systematic use of body terminals to improve small-signal and large-signal performance. The circuit has a high open-loop voltage gain and uses cascoded current mirror topologies, resulting in precise voltage and current transfer with bandwidths of 1.33 MHz and 2.13 MHz, respectively. The CCII offers a linear current drive up to 2.5 µA while consuming a total quiescent current of 2.86 µA (758 nA in the output branches), displaying one the highest figures of merit in terms of current utilization for sub 1 V solutions.
An Institutional Shift from Routine to Selective Diversion of Low Anastomosis in Robotic TME Surgery for Rectal Cancer Patients Using the KHANS Technique: A Single-Centre Cohort Study
Authors: Duhoky Rauand , Piozzi Guglielmo Niccolò , Rutgers Marieke L. W. , Mykoniatis Ioannis , Siddiqi Najaf , Naqvi Syed , Khan Jim S.
Published: July 2024

(1) Background: In recent years, there has been a change in practice for diverting stomas in rectal cancer surgery, shifting from routine diverting stomas to a more selective approach. Studies suggest that the benefits of temporary ileostomies do not live up to their risks, such as high-output stomas, stoma dysfunction, and reoperation. (2) Methods: All rectal cancer patients treated with a robotic resection in a single tertiary colorectal centre in the UK from 2013 to 2021 were analysed. In 2015, our unit made a shift to a more selective approach to temporary diverting ileostomies. The cohort was divided into a routine diversion group treated before 2015 and a selective diversion group treated after 2015. Both groups were analysed and compared for short-term outcomes and morbidities. (3) Results: In group A, 63/70 patients (90%) had a diverting stoma compared to 98/135 patients (72.6%) in group B (p = 0.004). There were no significant differences between the groups in anastomotic leakages (11.8% vs. 17.8%, p = 0.312) or other complications (p = 0.117). There were also no significant differences in readmission (3.8% vs. 2.6%, p = 0.312) or reoperation (3.8% vs. 2.6%, p = 1.000) after stoma closure. After 1 year, 71.6% and 71.9% (p = 1.000) of patients were stoma-free. One major reason for the delay in stoma reversal was the COVID-19 pandemic, which only occurred in group B (0% vs. 22%, p = 0.054). (4) Conclusions: A more selective approach to diverting stomas for robotic rectal cancer patients does not lead to more complications or leaks and can be considered in the treatment of rectal cancer tumours.
Epidermal Barrier Parameters in Psoriasis: Implications in Assessing Disease Severity
Authors: Morariu Silviu-Horia , Cotoi Ovidiu Simion , Tiucă Oana Mirela , Crișan Maria , Garaga Liuba , Tiucă Robert Aurelian , Mariean Claudia Raluca , Buicu Florin Corneliu , Nicolescu Alin Codrut
Published: July 2024

Psoriasis is characterized by an aberrant immune response due to myeloid dendritic cells and T helper cells intertwining with keratinocyte hyperproliferation. Skin integrity alterations may predispose patients to physiological imbalances, such as xerosis, reduced elasticity, and increased friability. This study aims to assess the epidermal barrier dysfunction in chronic plaque psoriasis and gain a comprehensive view of the dynamic changes in the epidermal barrier during various topical therapies. Adult patients with chronic plaque psoriasis were enrolled in this observational study. For each patient, skin barrier parameters, stratum corneum hydration (SCH), transepidermal water loss (TEWL), elasticity, erythema, and melanin levels were measured in lesional and non-lesional skin. Two extensions of the initial study design, with subsequent epidermal barrier determinations, were made as follows: one in which patients with moderate psoriasis were treated with clobetasol propionate 0.5% and the second one in which mild psoriasis was treated with either clobetasol propionate 0.5% or clobetasol propionate 0.5% with 10% urea. TEWL and erythema were found to be higher in the sites affected by psoriatic lesions than the unaffected sites, while SCH and elasticity were decreased. Severe psoriasis presented with higher TEWL (p = 0.032), erythema (p = 0.002), and lower SCH (p < 0.001) compared with the mild and moderate forms. SCH significantly improved during clobetasol propionate 0.5% treatment (p = 0.015). Clobetasol propionate 0.5% with 10% urea was found to be superior to clobetasol propionate 0.5% in improving TEWL and SCH in psoriasis.
Trends in Urban Vegetation Growth in China from 2000 to 2022
Authors: Yu Fang-Jie , Yan Li
Published: July 2024

Over the past two decades, urbanization in China has been advancing rapidly. The intricate effects of urbanization on vegetation growth in the urban core have been studied and reported. However, the percentage of impervious surfaces in the urban core, as defined in previous studies, was relatively low, and included some pixels containing farmland and water bodies. Consequently, their results may be affected by urbanization processes, such as the transformation of land types. Hence, this paper extracted 100% impervious surfaces from 2000 to 2022 as urban core areas in China using a 30 m resolution China land cover dataset (CLCD), which completely excluded the effect of urbanization itself on the experimental results, obtaining the trend of vegetation change in the real urban core area. Employing the remote sensing imagery of the Enhanced Vegetation Index (EVI) from 2000 to 2022, we analyzed the growth of vegetation in 1559 urban cores and the surrounding rural areas in China. The study’s findings revealed that the majority of the core areas (85.3%) studied in this paper exhibited a significant (p < 0.05) increase in vegetation, indicating that the various urban greening policies in China have been effective. However, only about 23.7% (369) of the urban core areas showed a faster increase in vegetation than the rural areas. This suggests that for most urban cores (1190), vegetation increase is not as pronounced as it is in surrounding rural areas. Additionally, the EVI rate of change in the urban cores obtained using CLCD versus MODIS land cover data significantly differed. The latter obtained a less pronounced trend of vegetation growth compared to the former, attributable to the disparity in their spatial resolution and the methodology used to define urban areas. The study underscores the importance of vegetation growth and its distribution in various urban core areas to comprehend the dynamics of urban cores’ vegetation growth and to offer insights for the subsequent formulation of greening policies. Moreover, data with different resolutions will significantly impact the results, thus highlighting the necessity of employing high spatial resolution data for more comprehensive research.
Synthesis of Heterostructured TiO2 Nanopores/Nanotubes by Anodizing at High Voltages
Authors: Tuan Ta Quoc , Toan Le Van , Pham Vuong-Hung
Published: July 2024

This paper reports on the coating of heterostructured TiO2 nanopores/nanotubes on Ti substrates by anodizing at high voltages to design surfaces for biomedical implants. As the anodized voltage from 50 V to 350 V was applied, the microstructure of the coating shifted from regular TiO2 nanotubes to heterostructured TiO2 nanopores/nanotubes. In addition, the dimension of the heterostructured TiO2 nanopores/nanotubes was a function of voltage. The electrochemical characteristics of TiO2 nanotubes and heterostructured TiO2 nanopores/nanotubes were evaluated in simulated body fluid (SBF) solution. The creation of heterostructured TiO2 nanopores/nanotubes on Ti substrates resulted in a significant increase in BHK cell attachment compared to that of the Ti substrates and the TiO2 nanotubes.
Structure and Selected Properties of SnO2 Thin Films
Authors: Kania Aneta , Szindler Magdalena M. , Szindler Marek , Brytan Zbigniew , Łoński Wojciech
Published: July 2024

Magnesium and its alloys are attractive temporary implants due to their biocompatibility and biodegradability. Moreover, Mg has good mechanical and osteoinductive properties. But magnesium and Mg alloys have one significant disadvantage: poor corrosion resistance in a physiological environment. Hence, a deposition of various layers on the surface of Mg alloys seems to be a good idea. The purpose of the article is to analyze the structure and morphology of two MgCa2Zn1 and MgCa2Zn1Gd3 alloys coated by SnO2 ALD (atomic layer deposition) films of various thickness. The studies were performed using scanning electron microscopy (SEM), X-ray fluorescence (XRF), and an X-ray diffractometer. The corrosion activity of the thin films and substrate alloys in a chloride-rich Ringer’s solution at 37 °C was also observed. The corrosion tests that include electrochemical, immersion measurements, and electrochemical impedance spectroscopy (EIS) were evaluated. The results indicated that SnO2 had a heterogeneous crystal structure. The surfaces of the thin films were rough with visible pores. The corrosion resistance of SnO2 measured in all corrosion tests was higher for the thicker films. The observations of corrosion products after immersion tests indicated that they were lamellar-shaped and mainly contained Mg, O, Ca, and Cl in a lower concentration.
Preparation and Immobilization Mechanism of Red Mud/Steel Slag-Based Geopolymers for Solidifying/Stabilizing Pb-Contaminated Soil
Authors: Wang Xinyang , Xue Yongjie
Published: July 2024

Pb-contaminated soil poses serious hazards to humans and ecosystems and is in urgent need of remediation. However, the extensive use of traditional curing materials such as ordinary Portland cement (OPC) has negatively impacted global ecology and the climate, so there is a need to explore low-carbon and efficient green cementitious materials for the immobilization of Pb-contaminated soils. A red mud/steel slag-based (RM/SS) geopolymer was designed and the potential use of solidifying/stabilizing heavy metal Pb pollution was studied. The Box–Behnken design (BBD) model was used to design the response surface, and the optimal preparation conditions of RM/SS geopolymer (RSGP) were predicted by software of Design-Expert 8.0.6.1. The microstructure and phase composition of RSGP were studied by X-ray diffractometer, Fourier transform infrared spectrometer, scanning electron microscopy and X-ray photoelectron spectroscopy, and the immobilization mechanism of RSGP to Pb was revealed. The results showed that when the liquid–solid ratio is 0.76, the mass fraction of RM is 79.82% and the modulus of alkali activator is 1.21, the maximum unconfined compressive strength (UCS) of the solidified soil sample is 3.42 MPa and the immobilization efficiency of Pb is 71.95%. The main hydration products of RSGP are calcium aluminum silicate hydrate, calcium silicate hydrate and nekoite, which can fill the cracks in the soil, form dense structures and enhance the UCS of the solidified soil. Pb is mainly removed by lattice immobilization, that is, Pb participates in geopolymerization by replacing Na and Ca to form Si-O-Pb or Al-O-Pb. The remaining part of Pb is physically wrapped in geopolymer and forms Pb(OH)2 precipitate in a high-alkali environment.
Electronic Properties and Mechanical Stability of Multi-Ion-Co-Intercalated Bilayered V2O5
Authors: Ma Chunhui , Zhou Bo
Published: July 2024

Incorporating metal cations into V2O5 has been proven to be an effective method for solving the poor long-term cycling performance of vanadium-based oxides as electrodes for mono- or multivalent aqueous rechargeable batteries. This is due to the existence of a bilayer structure with a large interlayer space in the V2O5 electrode and to the fact that the intercalated ions act as pillars to support the layered structure and facilitate the diffusion of charged carriers. However, a fundamental understanding of the mechanical stability of multi-ion-co-intercalated bilayered V2O5 is still lacking. In this paper, a variety of pillared vanadium pentoxides with two types of co-intercalated ions were studied. The root-mean-square deviation of the V-O bonds and the elastic constants calculated by density functional theory were used as references to evaluate the stability of the intercalated compounds. The d-band center and electronic band structures are also discussed. Our theoretical results show that the structural characteristics and stability of the system are quite strongly influenced by the intercalating strategy.
Verification of the Laser Powder Bed Fusion Performance of 2024 Aluminum Alloys Modified Using Nano-LaB6
Authors: Yao Zeyu , Xie Ziwen
Published: July 2024

The application of 2024 aluminum alloy (comprising aluminum, copper, and magnesium) in the aerospace industry is extensive, particularly in the manufacture of seats. However, this alloy faces challenges during laser powder bed fusion (PBF-LB/M) processing, which often leads to solidification and cracking issues. To address these challenges, LaB6 nanoparticles have been investigated as potential grain refiners. This study systematically examined the impact of adding different amounts of LaB6 nanoparticles (ranging from 0.0 to 1.0 wt.%) on the microstructure, phase composition, grain size, and mechanical properties of the composite material. The results demonstrate that the addition of 0.5 wt.% LaB6 significantly reduces the average grain size from 10.3 μm to 9 μm, leading to a significant grain refinement effect. Furthermore, the tensile strength and fracture strain of the LaB6-modified A2024 alloy reach 251 ± 2 MPa and 1.58 ± 0.12%, respectively. These findings indicate that the addition of appropriate amounts of LaB6 nanoparticles can effectively refine the grains of 2024 aluminum alloy, thereby enhancing its mechanical properties. This discovery provides important support for the broader application of 2024 aluminum alloy in the aerospace industry and other high-performance fields.
Mechanical Properties of Silicon Carbide Composites Reinforced with Reduced Graphene Oxide
Authors: Broniszewski Kamil , Woźniak Jarosław , Cygan Tomasz , Moszczyńska Dorota , Olszyna Andrzej
Published: July 2024

This article presents research on the influence of reduced graphene oxide on the mechanical properties of silicon carbide matrix composites sintered with the use of the Spark Plasma Sintering method. The produced sinters were subjected to a three-point bending test. An increase in flexural strength was observed, which reaches a maximum value of 503.8 MPa for SiC–2 wt.% rGO composite in comparison to 323 MPa for the reference SiC sample. The hardness of composites decreases with the increase in rGO content down to 1475 HV10, which is correlated with density results. Measured fracture toughness values are burdened with a high standard deviation due to the presence of rGO agglomerates. The KIC reaches values in the range of 3.22–3.82 MPa*m1/2. Three main mechanisms responsible for the increase in the fracture toughness of composites were identified: bridging, deflecting, and branching of cracks. Obtained results show that reduced graphene oxide can be used as a reinforcing phase to the SiC matrix, with an especially visible impact on flexural strength.
Deformation Behavior of AZ31 Magnesium Alloy with Pre-Twins under Biaxial Tension
Authors: Dai Hanshu , Sun Mengmeng , Cheng Yao
Published: July 2024

In the present study, the mechanical response and deformation behavior of a Mg AZ31 plate with different types of pre-twins was systematically investigated under biaxial tension along the normal direction (ND) and transverse direction (TD) with different stress ratios. The results show that significant hardening was observed under biaxial tension. The yield values in the direction of larger stress values were higher than those under uniaxial loading conditions, and the solute atom segregation at twin boundaries generates more obvious strengthening effect. Noting that, for TRH (with cross compression along the rolling direction (RD) and TD and annealing at 180 °C for about 0.5 h) sample, the strength effect of the RD yield stress σRD:σND = 2:1 was higher than that of the ND yield stress under stress ratio σRD:σND = 1:2. There is a complex competition between twinning and detwinning under biaxal tension along the ND and TD of the pre-twinned samples with the variation in the stress ratio along the TD and RD. The variation in the twin volume fractions for all samples under biaxial firstly decreases and then increases with a higher stress ratio along the ND. As for the TDH sample (precompression along the TD and annealing), the changes of the twin volume fraction were lower than that of the TR sample (cross compression along the TD and RD). However, the amplitude of variation in twin volume fraction of the TRH sample is higher than that of the TR sample. This is because the relative activity of detwinning decreases and that of twinning increases, as the ND stress mainly leads to the growth of pre-twins and the TD stress often promotes detwinning of primary twins. With a higher stress ratio along the ND, the activity of twinning deformation increases and that of detwinning decreases.
Parabolic Hessian Quotient Equation in Exterior Domain
Authors: Zhao Huawei , Dai Limei
Published: July 2024

This study mainly focuses on the parabolic Hessian quotient equation in the exterior domain. The existence and uniqueness of generalized parabolically symmetric solutions with generalized asymptotic behavior are proven using Perron’s method.
Influence of Iron and Magnesium on Fouling Properties of Organic Matter Solution in Membrane Process
Authors: Alresheedi Mohammad T.
Published: July 2024

Organic matter has been identified as a significant type of foulant in membrane processes for water treatment. Its fouling tendency is highly affected by the presence of ions and inorganics. While the effects of ions addition on organic fouling have been extensively researched in the past, studies on the effect of positively-charged inorganics, such as Fe2+ and Mg2+, on organic fouling are limited. This study investigates the influence of Fe2+ and Mg2+ addition on fouling properties of the Suwannee River Organic Matter (SROM) solution in the MF process, with and without Ca2+ ions. Results showed that increasing the concentration of Fe2+ and Mg2+ from 0–5 mM promoted SROM fouling, and resulted in an increased flux decline up to 33% and 58%, respectively. Cake layer resistance became more dominant with the addition of Fe2+ and Mg2+, and was counted for more than 60% of the fouling. Mg2+, however, caused higher internal pore blocking, and facilitated the formation of a less permeable cake layer, compared to Fe2+. This was evident in the analysis of the cake layer properties and the visualization of the fouling layer. In all cases, SROM fouling with Fe2+ and Mg2+ worsened with the addition of Ca2+ ions. The results of the study indicated the importance of understanding the interaction between organic matter and Fe2+ and Mg2+, which would provide useful insights on their fouling mechanism and control.
Influence of the Glycidyl Azide Polymer on the Energy Release of Aluminum Sub-Micron Particles under Ultrafast Heating Rates Stimulated by Electric Explosion and Solid Laser
Authors: Li Yaru , Ren Hui , Liu Shuo
Published: July 2024

Glycidyl azide polymer (GAP)-coated sub-micron aluminum (sub-mAl@GAP) particles exhibit higher heat release than their uncoated counterparts under low heating rates. However, their application in explosives has been hindered due to a lack of understanding of their energy release characteristics under heating rates of detonation levels. To address this problem, the energy release performances of sub-mAl@GAP particles under ultrafast heating rates stimulated by an electric explosion of wire and high-energy laser were studied. The results showed that the reaction of sub-mAl@GAP particles was more violent than that of an uncoated counterpart under an electric explosion stimulus. Additionally, the reaction time of the former was 0.4 ms shorter than that of the latter. In addition, the propagations of shock waves of the sub-mAl@GAP and sub-mAl were analyzed. The propagation distances of shock waves of the sub-mAl@GAP were all longer than those of sub-mAl under laser fluences of 0.5 J/cm2, 1.2 J/cm2, and 2.4 J/cm2. The distance difference gradually increased with the decrease in the laser fluence. Under a laser fluence of 0.5 J/cm2, the velocity and distance differences of the sub-mAl@GAP and sub-mAl were both the largest due to the energy contribution from the GAP. In conclusion, the fast decomposition rate of the GAP and its energy contribution would benefit the energy release of sub-mAl under ultrafast heating rates.
Thixoforming of the Hot Extruded Aluminum AlSi9Cu3(Fe) Machining Chips
Authors: Krolo Jure , Dumanić Labetić Ivana , Lela Branimir , Bilušić Martin
Published: July 2024

The main aim of this research was to investigate the aluminum AlSi9Cu3(Fe) machining chips recycling possibility utilizing a direct hot extrusion process and thixoforming. The thixo feedstock was prepared directly from the aluminum alloy AlSi9Cu3(Fe) machining chips waste without any remelting step. The machining chips were compacted, and direct hot extruded to create the solid samples and thixo feedstock. The aluminum alloy AlSi9Cu3(Fe) machining chips had a high degree of plastic deformation and after extrusion and heating in the semisolid temperature range, the suitable globular microstructure was achieved, which is a precondition for a successful thixoforming process. This approach can be characterized as a semisolid recycling process with a lower energy consumption, a higher material yield, and reduced greenhouse gas emissions into the atmosphere compared with conventional casting and recycling. Optical metallography, scanning electron microscopy accompanied with energy dispersive spectroscopy, electrical conductivity, and mechanical properties investigation were performed on the reference casted sample with a dendritic microstructure, the extruded sample with a severely deformed microstructure, and finally the thixoformed samples with a globular microstructure produced with different parameters, according to the Taguchi L4 (23) experimental plan.
Wave Impedance Determination for PCB SIWs Considering Metal Roughness Loss Effects
Authors: Serrano-Serrano María Teresa , Torres-Torres Reydezel
Published: July 2024

This paper presents an expression to determine the complex wave impedance of a substrate-integrated waveguide for the dominant TE10 propagation mode, notably enhancing the accuracy in modeling the corresponding imaginary part. This was accomplished by systematically identifying the need to consider additional conductor losses caused by the interaction of the propagating fields with the conductor material. In fact, by using the proposed expression, the complex impedance can straightforwardly be determined by combining propagation constant data, and the resistance that represents the loss associated with longitudinal currents occurring at the top and bottom walls, which are influenced by the conductor surface roughness. This allows for completely describing the characteristics of the waveguide when assuming uniform propagation along its length. Furthermore, since the voltage–current, the power–current, and the power–voltage impedances can easily be obtained from the wave impedance, the proposal enables representing the matching characteristics of the waveguide for circuit design purposes. An agreement between simulated and experimental insertion loss is achieved for substrate-integrated waveguides of two different widths when reconstructing the corresponding S-parameters using the determined wave impedance.
Positive Effects of Guanidinium Salt Post-Treatment on Multi-Cation Mixed Halide Perovskite Solar Cells
Authors: Aidarkhanov Damir , Idu Ikenna Henry , Zhou Xianfang , Duan Dawei , Wang Fei , Hu Hanlin , Ng Annie
Published: July 2024

As one of the most promising photovoltaic technologies, perovskite solar cells (PSCs) exhibit high absorption coefficients, tunable bandgaps, large carrier mobilities, and versatile fabrication techniques. Nevertheless, the commercialization of the technology is hindered by poor material stability, short device lifetimes and the scalability of fabrication techniques. To address these technological drawbacks, various strategies have been explored, with one particularly promising approach involving the formation of a low-dimensional layer on the surface of the three-dimensional perovskite film. In this work, we demonstrate the use of guanidinium tetrafluoroborate, CH6BF4N3, (GATFB) as a post-treatment step to enhance the performance of PSCs. Compared with the control sample, the application of GATFB improves the film surface topology, reduces surface defects, suppresses non-radiative recombination, and optimizes band alignment within the device. These positive effects reduce recombination losses and enhance charge transport in the device, resulting in PSCs with an open-circuit voltage (VOC) of 1.18 V and a power conversion efficiency (PCE) of 19.7%. The results obtained in this work exhibit the potential of integrating low-dimensional structures in PSCs as an effective approach to enhance the overall device performance, providing useful information for further advancement in this rapidly evolving field of photovoltaic technology.
Synthesis, Structural Analysis, and Peroxidase-Mimicking Activity of AuPt Branched Nanoparticles
Authors: Nuti Silvia , Fernández-Lodeiro Javier , Palomo Jose M. , Capelo-Martinez José-Luis , Lodeiro Carlos , Fernández-Lodeiro Adrián
Published: July 2024

Bimetallic nanomaterials have generated significant interest across diverse scientific disciplines, due to their unique and tunable properties arising from the synergistic combination of two distinct metallic elements. This study presents a novel approach for synthesizing branched gold–platinum nanoparticles by utilizing poly(allylamine hydrochloride) (PAH)-stabilized branched gold nanoparticles, with a localized surface plasmon resonance (LSPR) response of around 1000 nm, as a template for platinum deposition. This approach allows precise control over nanoparticle size, the LSPR band, and the branching degree at an ambient temperature, without the need for high temperatures or organic solvents. The resulting AuPt branched nanoparticles not only demonstrate optical activity but also enhanced catalytic properties. To evaluate their catalytic potential, we compared the enzymatic capabilities of gold and gold–platinum nanoparticles by examining their peroxidase-like activity in the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB). Our findings revealed that the incorporation of platinum onto the gold surface substantially enhanced the catalytic efficiency, highlighting the potential of these bimetallic nanoparticles in catalytic applications.
Anti-Obesity Activity of Sanghuangporus vaninii by Inhibiting Inflammation in Mice Fed a High-Fat Diet
Authors: Hao Jie , Jin Xinghui , Li Zhige , Zhu Yanfeng , Wang Lu , Jiang Xue , Wang Di , Qi Liangliang , Jia Dongxu , Gao Bo
Published: July 2024

Obesity is an unhealthy condition associated with various diseases characterized by excess fat accumulation. However, in China, the prevalence of obesity is 14.1%, and it remains challenging to achieve weight loss or resolve this issue through clinical interventions. Sanghuangpours vaninii (SPV) is a nutritional fungus with multiple pharmacological activities and serves as an ideal dietary intervention for combating obesity. In this study, a long-term high-fat diet (HFD) was administered to induce obesity in mice. Different doses of SPV and the positive drug simvastatin (SV) were administered to mice to explore their potential anti-obesity effects. SPV regulated weight, serum lipids, and adipocyte size while inhibiting inflammation and hepatic steatosis. Compared with the vehicle-treated HFD-fed mice, the lowest decreases in total cholesterol (TC), triglycerides (TG), and low-density lipoprotein cholesterol (LDL-C) were 9.72%, 9.29%, and 12.29%, respectively, and the lowest increase in high-density lipoprotein cholesterol (HDL-C) was 5.88% after treatment with different doses of SPV. With SPV treatment, the analysis of gut microbiota and serum lipids revealed a significant association between lipids and inflammation-related factors, specifically sphingomyelin. Moreover, Western blotting results showed that SPV regulated the toll-like receptor (TLR4)/nuclear factor kappa B (NF-κB) signaling pathway in HFD-diet mice, which is related to inflammation and lipid metabolism. This research presents empirical proof of the impact of SPV therapy on obesity conditions.
Methods of Determining Energy Expenditure in Individuals with Prader-Willi Syndrome: A Systematic Literature Review
Authors: Halilagic Anela , Longmore Danielle K. , Gilbertson Heather , Moschonis George
Published: July 2024

Prader-Willi syndrome (PWS) is a rare disorder characterised by varying nutritional phases that occur throughout the lifespan, ranging from failure to thrive to hyperphagia. If uncontrolled, the imbalance between energy intake and expenditure results in obesity development and increased morbidity and mortality risk. Although measures of energy requirements for accurate nutrition assessment are vital, the evidence appears sparse and heterogeneous; hence, the aim of this review was to examine the available literature on energy expenditure predicted or measured using various methods in individuals with PWS. Studies were sought that presented methods and results on resting energy expenditure or basal metabolic rate. A narrative synthesis was completed to present the study characteristics and results. Methods of determining energy requirements included predictive equations and indirect calorimetry. Differences amongst ages, growth hormone therapy, fasting status, and measures in which results were presented were limitations to appropriately summarising and identifying trends in energy expenditure. Indirect calorimetry was identified as the most accurate method; however, it is not widely available in all settings. Further research is encouraged to support the development of valid and reliable predictive equations that will better inform and improve the efficiency of clinical practice in supporting people with PWS.