bluuebunny/crossref_metadata_2025 huggingface dataset:
The liver cancer immune microenvironment: Therapeutic implications for hepatocellular carcinoma
Authors: Donne Romain , Lujambio Amaia
Published: August 2022

The liver is the sixth most common site of primary cancer in humans and the fourth leading cause of cancer‐related death in the world. Hepatocellular carcinoma (HCC) accounts for 90% of liver cancers. HCC is a prevalent disease with a progression that is modulated by the immune system. Half of the patients with HCC receive systemic therapies, traditionally sorafenib or lenvatinib, as a first‐line therapy. In the last few years, immune‐checkpoint inhibitors (ICIs) have revolutionized cancer therapy and have gained an increased interest in the treatment of HCC. In 2020, the combination of atezolizumab (anti‐programmed death‐ligand 1) and bevacizumab (anti–vascular endothelial growth factor) improved overall survival over sorafenib, resulting in Food and Drug Administration (FDA) approval as a first‐line treatment for patients with advanced HCC. Despite these major advances, a better molecular and cellular characterization of the tumor microenvironment is still needed because it has a crucial role in the development and progression of HCC. Inflamed (hot) and noninflamed (cold) HCC tumors and genomic signatures have been associated with response to ICIs. However, there are no additional biomarkers to guide clinical decision‐making. Other immune‐targeting strategies, such as adoptive T‐cell transfer, vaccination, and virotherapy, are currently under development. This review provides an overview on the HCC immune microenvironment, different cellular players, current available immunotherapies, and potential immunotherapy modalities.
Partially automated driving has higher workload than manual driving: An on‐road comparison of three contemporary vehicles with SAE Level 2 features
Authors: Kim Jisun , Revell Kirsten , Langdon Pat , Bradley Mike , Politis Ioannis , Thompson Simon , Skrypchuk Lee , O'Donoghue Jim , Richardson Joy , Stanton Neville A.
Published: August 2022

Vehicles with SAE Level 2 automated features are already in active use on the road, and vehicles with Level 3 or 4 will be with us soon. Although the vehicles provide support for longitudinal and lateral control, partially automated driving experience is sometimes more demanding than manual driving. However, the effects of automated driving on workload in naturalistic conditions have not been extensively investigated, as most studies have been undertaken in driving simulators. This study aims to extend the current understanding about workload in partially automated driving on public roads. Drivers' perceived workload was assessed after conducting manual and automated driving activities using a small sample (N = 8). They performed driving tasks in three contemporary vehicles with SAE Level 2 features, in highway and urban environments. The comparative findings revealed that drivers' perceived workload was higher in partially automated driving than manual driving. Furthermore, perceived workload was higher in urban environments than highway environments and in less experienced drivers than more experienced drivers. Although the findings may need to be interpreted with caution due to the small sample size, they provide a future research agenda that can be built upon.
Case studies of robots and automation as health/safety interventions in small manufacturing enterprises
Authors: Lowe Brian D. , Hayden Marie , Albers James , Naber Steven
Published: August 2022

This article reviews the experiences of 63 case studies of small businesses (<250 employees) with manufacturing automation equipment acquired through a health/safety intervention grant program. The review scope included equipment technologies classified as industrial robots (n = 17), computer numerical control (CNC) machining (n = 29), or other programmable automation systems (n = 17). Descriptions of workers' compensation (WC) claim injuries and identified risk factors that motivated the acquisition of the equipment were extracted from grant applications. Other aspects of the employer experiences, including qualitative and quantitative assessment of effects on risk factors for musculoskeletal disorders (MSD), effects on productivity, and employee acceptance of the intervention were summarized from the case study reports. Case studies associated with a combination of large reduction in risk factors, lower cost per affected employee, and reported increases in productivity were CNC stone cutting system, CNC/vertical machining system, automated system for bottling, CNC/routing system for plastics products manufacturing, and a CNC/Cutting system for vinyl/carpet. Six case studies of industrial robots reported quantitative reductions in MSD risk factors in these diverse manufacturing industries: snack foods; photographic film, paper, plate, and chemical; machine shops; leather goods and allied products; plastic products; and iron and steel forging. This review of health/safety intervention case studies indicates that advanced (programmable) manufacturing automation, including industrial robots, reduced workplace musculoskeletal risk factors, and improved process productivity in most cases.
A relational view of shiftwork: Co‐scheduling with higher performers
Authors: Downes Patrick E. , Lee Ella Sareum
Published: August 2022

Research in HR has devoted little attention to the practice of scheduling shift workers into times and places to conduct their work. Relying upon the growing literature related to relational HR, we propose a relational view of scheduling that focuses on how employees' social contexts—particularly their being co‐scheduled with higher performers—relate to changes in performance over time. We apply resource dependence and social learning theories to describe how employees' performance over time depends upon their working alongside higher performers. Higher performers consume limited resources (thereby constraining peers' performance in the short term), yet also provide instructive role models for learning new skills (thereby elevating peers' performance over the longer term). We further hypothesize these effects are stronger for employees who are newer to the firm in contrast to those with more experience. We analyze scheduling and performance data from 7,893 retail sales representatives over a 1‐year period. Results show co‐scheduling with higher performers has an immediate negative effect on employee performance, but is positively related to employee performance over time. Unexpectedly, co‐scheduling effects were present for all employees and not only for those new to the organization. Our study points to the need for HR research on employee scheduling to better understand how shift workers' schedules provide the relational context for their work. The research offers several theoretical contributions in understanding the peer effects of higher performers, and we offer practical implications for managers seeking to design employees' schedules to encourage organizationally advantageous relationships between coworkers.
Sex differences in metastatic surgery following diagnosis of synchronous metastatic colorectal cancer
Authors: Ljunggren Malin , Weibull Caroline E. , Palmer Gabriella , Osterlund Emerik , Glimelius Bengt , Martling Anna , Nordenvall Caroline
Published: August 2022

The aim was to investigate gender differences in the likelihood to receive metastatic surgery, and to compare overall survival between men and women, among patients with synchronous metastatic colorectal cancer (mCRC) in a population‐based setting. All Swedish adult patients diagnosed with synchronous mCRC in 2007‐2016 were identified using the nationwide colorectal cancer database (CRCBaSe). Unadjusted and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using logistic regression, comparing the odds of receiving treatment. The Kaplan‐Meier method was used to calculate survival proportions and Cox regression models to estimate hazard ratios (HRs) and 95% CIs of all‐cause mortality rates. All multivariable models were adjusted for age, ASA score, Charlson comorbidity index, year of diagnosis, location of primary tumor and single or multiple metastatic locations. A total of 12 201 patients met the study criteria. Women received 23% less metastatic surgery for mCRC (adjusted OR = 0.77, CI:0.69‐0.86) and experienced a slightly higher mortality following diagnosis (adjusted HR = 1.09, CI:1.05‐1.14). In analyses restricted to patients who received metastatic surgery, no significant differences in mortality were found. In conclusion, this population‐based study showed that women less often received metastatic surgery of mCRC and experienced slightly higher all‐cause mortality compared with men. The differences persisted despite adjustments of patient and cancer characteristics. Gender differences in receiving treatment are unacceptable if the underlying explanation cannot be motivated. Further studies are needed to understand if the differences are based on sex (i.e., biology) or gender (including clinically unmotivated differences in treatment approach).
ROS1 genomic rearrangements are rare actionable drivers in microsatellite stable colorectal cancer
Authors: Akhoundova Dilara , Hussung Saskia , Sivakumar Smruthy , Töpfer Antonia , Rechsteiner Markus , Kahraman Abdullah , Arnold Fabian , Angst Florian , Britschgi Christian , Zoche Martin , Moch Holger , Weber Achim , Sokol Ethan , Fritsch Ralph M.
Published: August 2022

c‐Ros oncogene 1, receptor tyrosine kinase (ROS1) genomic rearrangements have been reported previously in rare cases of colorectal cancer (CRC), yet little is known about the frequency, molecular characteristics, and therapeutic vulnerabilities of ROS1‐driven CRC. We analyzed a clinical dataset of 40 589 patients with CRC for ROS1 genomic rearrangements and their associated genomic characteristics (Foundation Medicine, Inc [FMI]). We moreover report the disease course and treatment response of an index patient with ROS1‐rearranged metastatic CRC. ROS1 genomic rearrangements were identified in 34 (0.08%) CRC samples. GOPC‐ROS1 was the most common ROS1 fusion identified (11 samples), followed by TTC28‐ROS1 (3 samples). Four novel 5′ gene partners of ROS1 were identified (MCM9, SRPK1, EPHA6, P4HA1). Contrary to previous reports on fusion‐positive CRC, ROS1‐rearrangements were found exclusively in microsatellite stable (MSS) CRCs. KRAS mutations were significantly less abundant in ROS1‐rearranged vs ROS1 wild type cases. The index patient presented with chemotherapy‐refractory metastatic right‐sided colon cancer harboring GOPC‐ROS1. Molecularly targeted treatment with crizotinib induced a rapid and sustained partial response. After 15 months on crizotinib disseminated tumor progression occurred and KRAS Q61H emerged in tissue and liquid biopsies. ROS1 rearrangements define a small, yet therapeutically actionable molecular subgroup of MSS CRC. In summary, the high prevalence of GOPC‐ROS1 and noncanonical ROS1 fusions pose diagnostic challenges. We advocate NGS‐based comprehensive molecular profiling of MSS CRCs that are wild type for RAS and BRAF and patient enrollment in precision trials.
Molecular mechanisms from reaction coordinate graph enabled multidimensional free energies illustrated on water dimer hydrogen bonding
Authors: Bruce‐Chwatt Tomás , Naidoo Kevin J.
Published: August 2022

Computing the free energies of molecular mechanisms in multidimensional space relies on combinations of geometrically complex reaction coordinates. We show how a graph theory implementation reduces complexity, and illustrate this on the arrangements of hydrogen bonding of a water dimer. The reaction coordinates and forces are computed using graphs that define the dependencies on the atoms in the Free Energy from Adaptive Reaction Coordinate Forces (FEARCF) library. The library can be interfaced with classical molecular dynamics as well as quantum molecular dynamics packages. Multidimensional interdependent reaction coordinates are constructed to produce complex free energy hypersurfaces. The reaction coordinates are graphed from atomic and molecular components to define points, distances, vectors, angles, planes and combinations thereof. The resultant free energy surfaces that are a function of the distance, angles, planes, and so on, can represent molecular mechanisms in reduced dimensions from the component atomic Cartesian coordinate degrees of freedom. The FEARCF library can be interfaced with any molecular package. Here, we demonstrate the link to NWChem to compute a hyperdimensional DFT (aug‐cc‐pVDZ basis set and X3LYP exchange correlation functionals) free energy space of a water dimer. Analysis of the water dimer free energy hypervolume reveals that while the chain and cyclic hydrogen bonding configurations are located in stable minimum energy wells, the bifurcated hydrogen bond configuration is a gateway to instability and dimer dissociation.
GLP1R inhibits the progression of endometrial carcinoma through activation of cAMP/PKA pathway
Authors: Li Wu , Gu Yanpin , Liu Songjun , Ruan Fan , Lv Wen
Published: August 2022

Background

This study strived to explore the role and mechanism of glucagon‐like peptide‐1 receptor (GLP1R) in endometrial carcinoma (EC).

Methods

In detail, after transfection of GLP1R overexpression vector and small interfering RNA targeting PKA, the mRNA expressions of GLP1R and PKA in EC cells (Ishikawa and RL95‐2) were quantified by quantitative reverse transcription polymerase chain reaction (qRT‐PCR). The cell biological behaviors, including proliferation, migration, invasion, and apoptosis, were detected using 5‐ethynyl‐2′‐deoxyuridine (EdU), wound healing, transwell, and flow cytometry assays, respectively. The cyclic adenosine monophosphate (cAMP) content and related protein expressions (GLP1R, p‐PKA, and PKA) were determined by enzyme‐linked immunosorbent assay (ELISA) and western blot. The effects of GLP1R and PKA on tumorigenesis were evaluated by measuring the tumor volume and weight of mice bearing EC.

Result

According to the results, GLP1R expression was downregulated in EC tissues and cells, and there was a positive correlation between GLP1R and PKA expressions. Upregulation of GLP1R promoted apoptosis and activated the cAMP/PKA signaling pathway in EC cells, while hindering the EC cell proliferation, invasion, migration, and the growth of tumor in mice. However, these effects were blunted by downregulation of PKA, which also accelerated the progression of EC in vitro and in vivo via inhibiting the activation of cAMP/PKA signaling pathway.

Conclusion

Collectively, upregulation of GLP1R impeded EC progression via inducing the activation of cAMP/PKA signaling pathway, which may be a potential treatment for EC.
A peptide translated from circPPP1R12A promotes the malignancy of non‐small cell lung cancer cells through AKT signaling pathway
Authors: Zhao Weijun , Xue Yibo , Zhang Yandan , Zhu Yonggang , Chen Zixuan , Zhao Xiaodong
Published: August 2022

Background

Recent literature have indicated that the malignancy of cancer cells is modulated by hsa_circ_0000423 (named circPPP1R12A) through the way of translating protein. Herein, we investigated the role and latent mechanisms of circPPP1R12A in Non‐Small Cell Lung Cancer (NSCLC).

Methods

CircPPP1R12A expression was measured by qRT‐PCR. The malignancy of NSCLC was determined by CCK‐8, TUNEL assay, Wound healing, Transwell and Western blotting assays. The underlying mechanisms of circPPP1R12A were confirmed by Western blotting and qRT‐PCR assays.

Results

CircPPP1R12A expression in NSCLC tissues was higher than that of neighboring normal tissues. CircPPP1R12A showed an upregulated expression in NSCLC cells. Upregulation of circPPP1R12A could promote the cell viability of NSCLC cells and reduce the apoptosis of NSCLC cells, while it could not promote cell invasion and migration. The reduction of cell viability and apoptosis was discovered in NSCLC cells with the silencing of circPPP1R12A, but circPPP1R12A knockdown does not inhibit cell invasion and migration. There was something interesting that circPPP1R12A encoding protein circPPP1R12A‐73aa was found in NSCLC cells. Mutations in circPPP1R12a‐73AA might disrupt the function of circPPP1ra‐73AA in A549 and H1299 cells. Next, we found that circPPP1R12A caused the increased growth of NSCLC cells by activating AKT signaling pathway.

Conclusion

In summary, our study proved that NSCLC cell proliferation was promoted by circPPP1R12A‐73aa translated from circPPP1R12A through the AKT pathway, which could throw some light on the understanding of the mechanism of NSCLC.
Flow cytometry assessment of reactive T‐cells distinguishes classic Hodgkin lymphoma from benign lymphadenopathy in children
Authors: Gao Hui , Cai Fengqing , Liu Lei , Shen Hongqiang
Published: August 2022

Background

Detection of classic Hodgkin lymphoma (cHL) neoplastic cells using flow cytometric immunophenotyping (FCI) remains limited. We hypothesized that characterization of the reactive infiltrates could assist in diagnosing cHL in children.

Methods

FCI using four‐color staining approaches was performed on 156 lymph node specimens with the following histopathologic diagnoses: cHL (25 cases), reactive lymphoid hyperplasia (RLH, 44 cases), and non‐Hodgkin lymphoma (87 cases).

Results

The overall concordance of FCI data with the histopathologic results of these cases was 81.4%. A reactive expansion of T‐cells with increased expression of CD45RO was present in the reactive infiltrate of cHL (CD45RO/CD3, 67.5%) and Epstein–Barr virus (EBV) infected RLH (62.7%) but not in EBV‐negative RLH (28.0%). The mean fluorescence intensity (MFI) of CD7 was higher for cHL and differed significantly from EBV‐positive RLH (138.5 vs. 63.8). A proposed diagnostic algorithm markedly elevated the overall concordance rate from 81.4% to 97.4%.

Conclusions

Immunophenotyping the reactive infiltrate of lymphoid tissue using flow cytometry is a reliable supplement to histopathology for the rapid diagnosis of pediatric cHL.
Leadership behaviors, attitudes and characteristics to support a culture of safety
Authors: Montminy Susan L.
Published: August 2022

It has been estimated that medical errors are the third highest‐ranking cause of death in the United States. A patient safety culture has been touted for many years as best practice to reduce medical error. While there is a general agreement of its importance, it has remained elusive for many. This study sought to learn how strengthening leadership skills within a health care organization could catalyze patient safety culture improvement. The research asked the following to gain an appreciation for that question: How does a leader ensure consistency in policies, practices, and protocols to create a patient safety culture? What attitudes, beliefs, and collective efficacy are needed to produce a patient safety culture? What leadership characteristics are needed to create a patient safety culture? The research participants were the employees who make up the patient safety department in a large academic health care system. Information was gathered to capture their view of leadership's role in patient safety culture and to gain knowledge relative to their individual experiences following a medical error.
MicroRNA and metabolomics signatures for adrenomyeloneuropathy disease severity
Authors: Turk Bela Rui , Poisson Laila Marie , Nemeth Christina Linnea , Goodman Jordan , Moser Ann B. , Jones Richard Owen , Fatemi Ali , Singh Jaspreet
Published: August 2022

Adrenomyeloneuropathy (AMN), the slow progressive phenotype of adrenoleukodystrophy (ALD), has no clinical plasma biomarker for disease progression. This feasibility study aimed to determine whether metabolomics and micro‐RNA in blood plasma provide a potential source of biomarkers for AMN disease severity. Metabolomics and RNA‐seq were performed on AMN and healthy human blood plasma. Biomarker discovery and pathway analyses were performed using clustering, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and regression against patient's clinical Expanded Disability Status Score (EDSS). Fourteen AMN and six healthy control samples were analyzed. AMN showed strong disease‐severity‐specific metabolic and miRNA clustering signatures. Strong, significant clinical correlations were shown for 7‐alpha‐hydroxy‐3‐oxo‐4‐cholestenoate (7‐HOCA) (r2 = 0.83, p < 0.00001), dehydroepiandrosterone sulfate (DHEA‐S; r2 = 0.82, p < 0.00001), hypoxanthine (r2 = 0.82, p < 0.00001), as well as miRNA‐432‐5p (r2 = 0.68, p < 0.00001). KEGG pathway comparison of mild versus severe disease identified affected downstream systems: GAREM, IGF‐1, CALCRL, SMAD2&3, glutathione peroxidase, LDH, and NOS. This feasibility study demonstrates that miRNA and metabolomics are a source of potential plasma biomarkers for disease severity in AMN, providing both a disease signature and individual markers with strong clinical correlations. Network analyses of affected systems implicate differentially altered vascular, inflammatory, and oxidative stress pathways, suggesting disease‐severity‐specific mechanisms as a function of disease severity.
Abusive supervision and knowledge hiding: The moderated mediation role of overall justice and gender
Authors: Koay Kian Yeik , Lim Pang Kiam
Published: August 2022

The purpose of this study is to examine the influence of abusive supervision on knowledge hiding via overall justice based on social exchange theory. In addition, using a moderated mediation framework, gender is proposed and tested as a moderator of the relationship between abusive supervision and knowledge hiding through overall justice, grounded in social role theory. Two hundred and forty‐three participants are recruited from public listed companies in Malaysia. Partial least squares structural equation modeling (PLS‐SEM) is used as the main analytic tool. The results reveal that abusive supervision has a significant negative influence on overall justice. In addition, both the influence of overall justice on knowledge hiding and the mediating effect of overall justice between abusive supervision and knowledge hiding is not significant. However, the influence of abusive supervision on knowledge hiding through overall justice is significant for males but not for females. The study contributes to the knowledge‐hiding literature by providing new insights into how males and females cope with abusive supervision to restore equity.
Derivation and validation of a prediction model for patients with lung nodules malignancy regardless of mediastinal/hilar lymphadenopathy
Authors: Liu Fenghui , Dai Liping , Wang Yulin , Liu Man , Wang Meng , Zhou Zhigang , Qi Yu , Chen Ruiying , OuYang Songyun , Fan Qingxia
Published: August 2022

Background

Clinical prediction models to classify lung nodules often exclude patients with mediastinal/hilar lymphadenopathy, although the presence of mediastinal/hilar lymphadenopathy does not always indicate malignancy. Herein, we developed and validated a multimodal prediction model for lung nodules in which patients with mediastinal/hilar lymphadenopathy were included.

Methods

A single‐center retrospective study was conducted. We developed and validated a logistic regression model including patients with mediastinal/hilar lymphadenopathy. Discrimination of the model was assessed by area under the operating curve. Goodness of fit test was performed via the Hosmer–Lemeshow test, and a nomogram of the logistic regression model was drawn.

Results

There were 311 cases included in the final analysis. A logistic regression model was developed and validated. There were nine independent variables included in the model. The aera under the curve (AUC) of the validation set was 0.91 (95% confidence interval [CI]: 0.85–0.98). In the validation set with mediastinal/hilar lymphadenopathy, the AUC was 0.95 (95% CI: 0.90–0.99). The goodness‐of‐fit test was 0.22.

Conclusions

We developed and validated a multimodal risk prediction model for lung nodules with excellent discrimination and calibration, regardless of mediastinal/hilar lymphadenopathy. This broadens the application of lung nodule prediction models. Furthermore, mediastinal/hilar lymphadenopathy added value for predicting lung nodule malignancy in clinical practice.
Hemi‐marsh concept prevails? Kaminski and Prince (1981) revisited
Authors: Masto Nicholas M. , Kaminski Richard M. , Prince Harold H.
Published: August 2022

The hemi‐marsh concept has prevailed in avian habitat selection and wetland ecology and management since the 1970s. Hemi‐marsh is a stage of wetland succession when approximately equal proportions of emergent vegetation and open water occur. In 1981, researchers reported on a field experiment in Delta Marsh, Manitoba, Canada, where they artificially created interspersion levels of emergent vegetation and open water (30%:70%, 50:50 [hemi‐marsh], and 70:30) by mowing or rototilling to test for hypothesized differences in indicated breeding pair indices (IBPs/ha; pairs + lone males) of dabbling ducks and species diversity among treatment combinations. Greatest dabbler densities and species diversity were in 50:50 hemi‐marsh plots. This research has been widely cited; however, the experiment was pseudo‐replicated because of non‐independence of IBP counts within and among weeks and years of surveys. We reanalyzed data from the study to support or refute original results. More robust and generalized analyses revealed vegetation:water interspersion characteristics influenced IBP densities of blue‐winged teal (Spatula discors), mallard (Anas platyrhynchos), gadwall (Mareca strepera), northern shoveler (S. clypeata), and species diversity. We estimated greatest IBP densities and species diversity in 50:50 hemi‐marsh plots, agreeing with the previous study. Including nested random effects to account for temporal pseudo‐replication improved model fits by 2–30%. Despite accounting for temporal variation in dabbler density and species diversity, 61–93% of variation remained unexplained, indicating unresolved complexities of breeding dabbler habitat use. Nonetheless, our reanalysis generalized and strengthened the original finding that dabbling duck densities and species diversity were greatest in hemi‐marsh plots. Managers may strive to reproduce hemi‐marsh conditions for dabbling ducks and evaluate other waterbird responses. Our reanalysis also emphasized the need for researchers to account for or prevent temporal and spatial pseudo‐replication, examine model fit, and provide reproducible documentation of data and code, especially now that analytical tools and databases are freely available.
Synthesis by Sol‐Gel Route, Chemical, and Biological Characterization of Hybrid Material Composed by Fe(II)C and poly(ε‐caprolactone)
Authors: Catauro Michelina , Blanco Ignazio , Fiorentino Marika , D'Angelo Antonio , Dell'Anna Maria Michela , Mastrorilli Piero
Published: August 2022

Sol–gel route represents a valuable technique to obtain functional materials, in which organic and inorganic components are closely connected. Imbalance of the iron level in the body causes several diseases. In particular, the low level of iron, during pregnancy, is responsible of the iron deficiency anemia, and even of neurodegenerative diseases. The aim of this work is the synthesis of iron (II) therapeutic systems by sol–gel method. Different weight percentages of poly(ε‐caprolactone) (PCL 7wt%) and ferrous citrate (Fe(II)C 6wt%) for drug delivery applications are embedded in a SiO2 matrix. Fourier transform infrared (FTIR) spectroscopy is used to study the interactions among different components in the hybrid materials. SiO2/Fe(II)C/PCL materials have been proposed as valuable antibacterial agents against Escherichia coli and Enterococcus faecalis.
Tribological Behavior of UHMWPE (Disc) against Ti6Al4V (Pin) under Different Lubrication Conditions
Authors: Visco Annamaria , Grasso Antonio , Scolaro Cristina , Belhamdi Hossem , Sili Andrea
Published: August 2022

The proposed research work is addressed to the study of the wear behavior of Ultra High Molecular Weight Polyethylene (UHMWPE) under the contact with a rounded pin in Ti6Al4V alloy, which is largely used for production of the last generation of prosthetic implants by electron beam manufacturing (EBM). The wear tests of UHMWPE in contact with a Ti6Al4V pin are carried out dry or in the presence of lubricants fluids that are characterized by tribological tests, wet‐ability measurements, and morphological observations of the contact surfaces. UHMWPE wear resistance improves in conditions of lubrication in the order: dry < distilled water < synthetic synovial < bovine serum, according to wettability results. As suggested by the track profiles, the contact action in dry can be mainly due to shear stress while that in lubricant mainly to compressive stress.
Thermal Influence on Physico‐Chemical Properties of Geopolymers Based on Metakaolin and Red Tomato Waste
Authors: Catauro Michelina , D'Angelo Antonio , Piccolella Simona , Leonelli Cristina , Dal Poggetto Giovanni
Published: August 2022

The high amount of organic and inorganic wastes has increased the attention to new strategies aiming to reduce the waste disposals. Organic wastes, such as tomato wastes (TWs), are a good source from which the red color can be obtained. Among the different technologies, the geopolymers had been proposed as a powerful technology able to incorporate various kinds of wastes. In this paper, pure metakaolin and a mixture obtained by adding 10% of red TW‐derived (peels) are consolidated by alkali activation at room temperature, 40 and 60°C without the pigment extraction. Fourier‐transform infrared (FTIR) spectra confirmed the geopolymerization occurrences. Moreover, the obtained materials are analyzed for their conductivity and pH after the sample extractions at different times. The integrity tests assessed the resistance of the synthesized geopolymers and the presence of red tomato‐wastes led to a release of yellow organic hydro‐soluble compounds. Finally, the weight loss confirmed the integrity test. Indeed, there are no differences at 16 and 30 d.
Nanocomposite Based on a Natural Anionic Polysaccharide for Anticancer Drug Immobilization
Authors: Spiridonov Vasily , Shibaeva Anna , Kusaia Victoriia , Zoirova Zukhra , Antonova Yulia , Yaroslavov Alexander
Published: August 2022

Synthesis of polymer nanocomposite as nanocontainers for doxorubicin (DOX) is carried out at a molar ratio of monomer units of the anionic polysaccharide (sodium hyaluronate) and Ca2+‐ions as a cross‐linking agent equaled to 10/1. Highly water‐soluble white fibrous products can be prepared. The hydrodynamic diameter of nanocompsite (Ca2+/Na‐Hyaluronate) particles is equal to 150 nm. At the same time, diameter of the original sodium hyaluronate (Na‐Hyaluronate) macromolecules is about 300 nm. The interaction between synthesized nanocomposite particles, Ca2+/Na‐Hyaluronate, and DOX accompanied by a new complex formation can be confirmed by means of fluorimetry. Obtained results indicate that the nanocomposite is capable as an immobilizing doxorubicin nanocontainer.
Inclusion Complexes Between β‐cyclodextrin and the Anticancer Drug 5‐Fluorouracil for its Solubilization: a Molecular Dynamics Study at Different Stoichiometries
Authors: Raffaini Giuseppina , Elli Stefano , Ganazzoli Fabio , Catauro Michelina
Published: August 2022

Cyclodextrins (CDs) are natural macrocyclic oligosaccharides able to solubilize hydrophobic drugs in water improving their bioavailability, thanks to favorable noncovalent interactions particularly in their hydrophobic cavity. Using a simulation protocol proposed in previous work, in this theoretical study based on Molecular Mechanics (MM) and Molecular Dynamics (MD) methods, inclusion complexes between β‐cyclodextrin and 5‐Fluorouracil (5‐FU) are investigated. 5‐FU is an anticancer drug hardly soluble in water used for more than 50 years. This drug is mainly administered by intravenous injection for the treatment of inner cancers or as a cream in the case of skin‐related cancers. For drug delivery applications, it is important to characterize stable inclusion complexes at different drug concentrations in order to enhance the anticancer activity by maintaining lower dose, thus reducing cytotoxic effects on the normal cells, causing several negative impacts in the course of treatment. In this work, the structure and stability of the host–guest complexes β‐CD:5‐FU in a 1:1 and 1:2 stoichiometries are investigated because this drug is relatively small compared to the size of the hydrophobic β‐CD cavity. The 5‐FU complexes with CDs allow its solubilization, thanks to favorable van der Waals interactions. Interestingly, these intermolecular interactions in inclusion complexes may also affect the release profile. MD simulations are a powerful tool to evaluate interactions between hydrophobic anticancer drugs and hydrophilic carriers with an inner hydrophobic cavity such as CDs and oligosaccharides in general.
Redesign of a 3D Low Cost Filament Printer, Adapting it to a Pellet Extruder for New Material Assays
Authors: Mosquera Alberto , Andrade Pamela , Cobos Christian , Cárdenas Eugenio , Ferrándiz Santiago
Published: August 2022

The present work arises from the need identified on the additive manufacturing field due to the lack of 3D low cost pellet printers and the little diversity of materials available for 3D FFF printing. Considering this problem, a 3D pellet printer design is proposed starting from a 3D FFF printer. To carry out this design work, at first it is selected a commercial pellet extruder which meets all the conditions to provide a proper printing quality. At second, a new mechanical propose is analyzed and tested by simulation programs considering the changes made. In the course of the mechanical analysis, the structure is reviewed, and also a temperature study is accomplished. Based on the results, it is possible to verify the correct performance of the machine. From the different simulations, the optimal conditions in terms of dimensioning, structure, internal temperatures, and loads are obtained. This enables to determine an optimal and functional design which adapts into a commercial pellet extruder keeping low costs and simple implementation.
The Effect of the Natural and Synthetic Porphyrin Complexes on the Structure and Properties of the Semi‐Crystalline Polymers
Authors: Tyubaeva Polina , Zykova Anna , Olkhov Anatoly , Lobanov Anton
Published: August 2022

Recently, nanocomposite fibrous materials with favorable functional properties are widely used in various fields, for example: conductive fibers, fiber‐optic sensors, materials for photonics, gene therapy, and biomedicine. The development of modern nanocomposite fibrous materials with valuable functional properties based on biodegradable semicrystalline polymers is an actual scientific problem. Moreover, the use of natural and biodegradable polymers as objects allows to approach the solution of an environmental problem, expanding the list of known ecofriendly materials for special purposes, expanding the areas of their practical application, including solving biomedical problems. Thus, the aim of the work is the development of a methodology for the directed design of biodegradable fibrous nanocomposites with specified properties. In the article, the methods of directed modification of semicrystalline polymers of natural origin (polyhydroxybutyrate) by modifying additives based on natural porphyrin complexes (hemin) are considered. Electrospinning is one of the most productive methods to obtain a highly developed well oriented structure with specified characteristics. The influence of additives on the polymeric fibrous structure and, as a result, on the properties of the electrospun material are investigated in the work.
Photo‐Degradation of a Biopolyester Blend under UV‐C Rays
Authors: Visco Annamaria , Scolaro Cristina , Bellhamdi Hossem , Grasso Antonio
Published: August 2022

Biopolyesters, pure and mixed with a compatibilizer, are exposed to UV‐C radiation in the interval 4–32 h. UV‐C rays act as germicides and antibacterial on biomedical materials. The mechanical and physical characterization tests have shown how all the materials, pure and mixed, undergo UV‐C photodegradation even if in a different way. The change in the structural order of the polymer, the embrittlement, and the change in the surface wettability of the water/blood is lower in the blend than in pure polymers. This is thanks to the cross‐linked structure of the mixture, which is more thermally stable, mechanically resistant, and more hydrophobic than the individual components.
Char Valorization into Sustainable and Performant Polyurethane Insulating Panels
Authors: Malchiodi Beatrice , Barbieri Luisa , Lancellotti Isabella , Pozzi Paolo
Published: August 2022

River maintenance is required for environmental risk management; however, the resulting vegetable biomass owns poor properties that preclude its treatment in an energy power plant. Nevertheless, the large availability of river biomass and a possible valorization of the by product from the gasification process (namely char, a fine‐grained vegetable carbon) can encourage and make this operation more sustainable. If the use of char as soil or substrate improver has been widely studied in the last 15 years, the application of this substance for construction materials or composites is starting to gain more attention recently. Indeed, in addition to the great advantage of carbon sequestration, the use of char can reduce the energy associated with the production process of such materials by decreasing the consumption of raw materials. In this work, char deriving from the gasification process of local river biomasses is fully characterized and used in different ratios in polyurethane panels for insulating purpose. Remarkably, polyurethane panels show an enhancement in thermal insulating power and electric conductivity by increasing the char content. Enhancements in terms of mechanical properties are also observed for maximum char content up to 1 wt%. In contrast, higher content results in preventing a good development of polymerization and consequently of good properties. Precisely, the char use significantly increases the maximum load in stress‐relaxation tests and improves the load recovery after 10 min, whereas higher elastic modulus and compressive strength values are observed in compressive tests. The char effectiveness toward more sustainable and performant insulating materials is demonstrated.
Properties of Rubber Blends Filled with Calcium Lignosulfonate
Authors: Hložeková Klaudia , Kruželák Ján , Džuganová Michaela , Hudec Ivan
Published: August 2022

The lignosulfonates are water‐soluble anionic polymers, which are considered as byproducts from the production of wood pulp using sulfite pulping. Calcium lignosulfonate is chosen as a filler according to previous research due to its effect on the properties of the blends. It is added in the concentration range from 10 to 60 phr to the blends with NBR, SBR, and EPDM. It is found out that the increasing concentration of filler has a favorable effect on the values of physical—mechanical properties of vulcanizates.
Comparison of Three Additive Manufacturing (AM) Techniques for Manufacturing Complex Hollow Composite Parts
Authors: Tosto Claudio , Pergolizzi Eugenio , Cicala Gianluca
Published: August 2022

Additive manufacturing (AM) is well known for supporting the manufacturing of composites through the 3D printing of lay‐up tools, sacrificial mandrels, trim molds, etc. The fused deposition modeling (FDM) is a pioneer in composite tooling. This technique is advantageous in many scenarios in which it is convenient to obtain hollow composite parts by dissolving sacrificial mandrels, removing the use of expensive and heavy metal molds. However, the effects that the removal process has on the thermomechanical properties of the composite must be considered. The convenience of another AM technique, liquid crystal display (LCD) printing, has also recently been demonstrated. The present work aims to compare three different techniques, FDM, fused filament fabrication (FFF), and LCD, each using different materials and, therefore, different mandrel removal processes. DMA analyses have highlighted the impact of some dissolution processes on thermomechanical properties. Further mechanical analysis is conducted to support what is found in the thermomechanical characterization tests. Finally, an economic analyses highlight the time and cost savings of some AM technologies compared to the conventional method for manufacturing composite parts.
Accelerated Photo‐Oxidation of Polyamide 11 Nanocomposites under Various Clays Nanofillers
Authors: Dehouche Nadjet , Kaci Mustapha , Focke Walter Wilhelm , Van Der Merwe Liezel
Published: August 2022

The effect of various clays nanofillers on the photo‐oxidation of polyamide 11 (PA11) has been investigated by accelerated ultraviolet (UV) test up to 780 h. Organo‐modified montmorillonite, halloysite nanotubes, and sepiolite were selected and incorporated separately to PA11 at 5 wt.%. The samples were prepared by melt compounding. Fourier transform infrared (FTIR) data showed a linear increase of carbonyl index (CI) in the first 360 h of exposure indicating a rapid oxidation of all samples without any induction period. Further, the nanocomposite samples exhibit faster oxidation kinetics than PA11, being however less pronounced for PA11/sepiolite. This is consistent with both the yellowing index (YI) evolution determined by UV–Vis spectroscopy and also the onset oxidation temperature (OOT) determined by differential scanning calorimetry (DSC).
Potential of Using Agricultural Waste Composites as Thermal Insulation Material
Authors: Serin Hasan , Güzel Gülşen , Kumlu Umut , Akar Mustafa Atakan
Published: August 2022

A huge amount of waste is produced every day in the world and it is thrown away without giving them any new use. Agricultural wastes generated as a result of obtaining, processing, and consuming plant and animal products constitute a remarkable large part of this waste amount. Today, these wastes are used in the production of composites, and the composites produced from these wastes give positive results in durability, flexibility, and thermal insulation. Composite materials which are combination of different materials to create a new material with discrete properties than its ingredients have gained great importance with the increment of product variety thus the property requirement. In production process, it is now always possible to fulfill the requirements of the design with conventional engineering materials. Since composite materials have the ability of being tailorable they have been started to be used in many different application areas. Recently, the usage of such composite materials in the automotive field has been evaluated. In this review, the usage of composites produced from different agricultural wastes in thermal insulation has been examined. A detailed review of the past and recent research activities has been documented. The literature survey reveals that agricultural wastes can be a good candidate to be used as reinforcement or filler material in composites for thermal insulation purposes.
Influences of Iron Oxide Nanomaterial and Hydrogen Addition into Sunflower Biodiesel/Diesel Powered Diesel Engine Performance and Emissions
Authors: Özcanlı Mustafa , Tosun Erdi , Çalık Ahmet
Published: August 2022

In this study, effects of iron oxide (Fe3O4) and hydrogen (H2) additions into 20% sunflower biodiesel + 80% diesel (B20) operated compression ignition engine performance and emissions are evaluated. Diesel fuel (D) is selected as a reference fuel for comparison purpose. Reduced performance level with B20 can be recovered with use of nanoparticle and hydrogen due to their superior combustion characteristics. In comparison to diesel, B20 mixture has caused to reduction on power by 6.44% while addition of nanoparticle and hydrogen (H_B20_Fe) have increased power by 5.76%. B20 mixture led to decrease carbon monoxide (CO) emission by 7.92% whereas nanoparticle and hydrogen addition have caused further decrement by 12.35% compared to diesel. Diesel shows best nitrogen oxides (NOx) emission characteristics of all. Increment levels are 7.24% and 12.94 for B20 and H_B20_Fe, respectively.
The Usage of Natural Fibers for Automotive Applications
Authors: Akar M. Atakan , Tosun A. Tuğçe , Yel Feyza , Kumlu Umut
Published: August 2022

Lightweighting studies of vehicles have gained great importance in recent years due to strict emission regulations and goals of more sustainable manufacturing. One of the solutions to produce lighter vehicles is to employ lighter alternative materials such as composites instead of conventional materials. Composite materials are generally fabricated with reinforcement of a matrix material with synthetic fibers such as glass, carbon, and aramid, but recently there is a great interest in natural fibers to substitute the synthetic fibers with biobased material which has the advantages of being green, biodegradable, renewable, and more sustainable. Thus, especially for automotive components, there are many studies to employ natural fibers instead of synthetic fibers. In this study, the recent studies on applications of natural fibers in automotive composites have been reviewed. The review study revealed that natural fibers are viable alternatives to synthetic ones and they are expected to be used more in near future.
Analysis of the Composite Structure of the Cornea‐Contact Lens Assembly in Orthokeratology
Authors: Bodi Gyury , Baritz Mihaela I. , Repanovici Angela , Barbu Daniela M.
Published: August 2022

Contact lenses are currently a practical and effective solution for the correction of refractive errors but also for the application of orthokeratology procedures in cases of keratoconus or high myopia pathologies. In orthokeratology procedures, the contact lenses used are rigid (hard) and are made of biocompatible materials resulting in a composite structure together with the cornea of the human eye. Thus, the contact lenses for orthokeratology have the effect of deforming the corneal surface, in the latter inducing a series of residual and inertial stress states through which changes in the refractive power of the entire eyeball are obtained. This paper presents aspects related to the approach of the corneal‐contact lens composite structure as a thin curved plate set. Also, the study is completed with the determination of the different aspects in section and an anisotropic structure which implies an approach of biomechanical behavioral analyzes both in terms of the elastic component and the viscosity component manifested in the corneal structure. As shown by specialists, the cornea topography is determined by the balanced state between the internal and external forces acting on it and its mechanical rigidity, which is, in turn, defined by the cornea geometry, the biomaterial thickness, and rigidity. Therefore, the development of studies on the corneal‐contact lens combination in orthokeratology as a composite structure is closest to the real behavior of the whole.
Application of Micro Electrical Discharge Machining and Electrochemical Machining in Manufacturing of Micro‐Electromechanical Systems: A Review
Authors: Enciu Cornel‐Cristian , Pârvu Gabriela‐Marina , Ghiculescu Liviu‐Daniel , Opran Constantin Gheorghe
Published: August 2022

The paper deals with the classification, applications, and advantages of microelectromechanical systems (MEMS), materials, and technologies used. This area of production represents one of the most promising technologies of 21st century, with a big impact in manufacturing 4.0. Nowadays, MEMS fabrication methods have a very big influence in the area of medicine, and therefore the review applications of utmost importance like micromechanical stents or antenna stents are related. The study presents information about MEMS based micro‐EDM, regarding working parameters and some examples of techniques used to realize MEMS devices. These have the purpose to minimize the cost together with the increase of the output technological parameters. The process capabilities of micro‐ECM, associated with working parameters are also treated, and the potential applications in industries like automotive, aerospace, biomedical, security, communication, etc. Finally, some future challenges of MEMS application in the specified fields are exposed.