bluuebunny/crossref_metadata_2025 huggingface dataset:
Manual Therapy versus Localisation (Tactile, Sensory Training) in Patients with Non-Specific Neck Pain: A Randomised Clinical Pilot Trial
Authors: Thomaidou Eleftheria , McCarthy Christopher James , Tsepis Elias , Fousekis Konstantinos , Billis Evdokia
Published: May 2023

Manual therapy (MT) techniques typically incorporate localised touch on the skin with the application of specific kinetic forces. The contribution of localised touch to the effectiveness of MT techniques has not been evaluated. This study investigated the immediate effects of MT versus localisation training (LT) on pain intensity and range of movement (ROM) for neck pain. In this single-blind randomised controlled trial thirty eligible neck pain volunteers (23 females and 7 males), aged 28.63 ± 12.49 years, were randomly allocated to MT or to a motionless (LT) group. A single three-minute treatment session was delivered to each group’s cervico-thoracic area. The LT involved tactile sensory stimulation applied randomly to one out of a nine-block grid. Subjects were asked to identify the number of the square being touched, reflecting a different location on the region of skin. MT involved three-minute anteroposterior (AP) glides and sustained natural apophyseal glides (SNAG) techniques. Pre- and post-intervention pain intensity were assessed using a pressure pain threshold (PPT) algometer and the numeric pain rating scale (NPRS). Neck ROM was recorded with a bubble inclinometer. Improvements in ROM and self-reported pain were recorded in both groups (p < 0.001) without differences in NPRS, ROM or PPT scores between groups (p > 0.05). Tactile sensory training (localisation) was as effective as MT in reducing neck pain, suggesting a component of MT’s analgesic effect to be related with the element of localised touch rather than the forces induced during passive movements.
Pulmonary Fat Embolism Following Liposuction and Fat Grafting: A Review of Published Cases
Authors: Kao Yu-Ming , Chen Kuo-Tai , Lee Kuo-Chang , Hsu Chien-Chin , Chien Yeh-Cheng
Published: May 2023

Background: One of the most severe complications of liposuction and fat grafting is pulmonary fat embolism (PFE). However, most healthcare workers are not familiar with PFE. We performed a systematic review to describe the details of PFE. Methods: PubMed, EMBASE, and Google Scholar were searched up to October 2022. Further analysis focused on clinical, diagnostic, and outcome parameters. Results: A total of 40 patients from 19 countries were included. Chest computed tomography (CT) yielded 100% accuracy in the diagnosis of PFE. More than 90% of the deceased died within 5 days after surgery, and in 69% of patients, onset of symptoms occurred within 24 h after surgery. The proportions of patients who required mechanical ventilation, had a cardiac arrest event, or died among all patients and among those whose onset of symptoms occurred within 24 h after surgery were 76%, 38%, and 34% versus 86%, 56%, and 54%, respectively. Conclusions: The earlier the onset of symptoms was, the more severe the clinical course was. Once a patient presents with PFE-related symptoms, surgery should be halted, supportive care initiated, and chest CT used to diagnose PFE. According to our review results, if a patient with PFE survives the initial episode without permanent sequelae, a complete recovery can be anticipated.
Ontological Model in the Identification of Emotional Aspects in Alzheimer Patients
Authors: Castillo Salazar David Ricardo , Lanzarini Laura , Gómez Héctor , Thirumuruganandham Saravana Prakash , Castillo Salazar Dario Xavier
Published: May 2023

The present work describes the development of a conceptual representation model of the domain of the theory of formal grammars and abstract machines through ontological modeling. The main goal is to develop an ontology capable of deriving new knowledge about the mood of an Alzheimer’s patient in the categories of wandering, nervous, depressed, disoriented or bored. The patients are from elderly care centers in Ambato Canton-Ecuador. The population consists of 147 individuals of both sexes, diagnosed with Alzheimer’s disease, with ages ranging from 75 to 89 years. The methods used are the taxonomic levels, the semantic categories and the ontological primitives. All these aspects allow the computational generation of an ontological structure, in addition to the use of the proprietary tool Pellet Reasoner as well as Apache NetBeans from Java for process completion. As a result, an ontological model is generated using its instances and Pellet Reasoner to identify the expected effect. It is noted that the ontologies come from the artificial intelligence domain. In this case, they are represented by aspects of real-world context that relate to common vocabularies for humans and applications working in a domain or area of interest.
A Longitudinal Study of Perceptions of the Massachusetts Menthol Ban and Its Impact on Smoking Behaviors among Marginalized Individuals
Authors: Booras Anna , Wiener Renda Soylemez , Maccarone Jennifer , Stokes Andrew C. , Fetterman Jessica L. , Hamburg Naomi M. , Singh Johar , Bulekova Katia , Kathuria Hasmeena
Published: May 2023

Menthol cigarettes have had a profound adverse effect on public health. On 1 June 2020, Massachusetts became the first state to ban the sale of menthol cigarettes. We explored how perceptions of the ban and smoking behaviors changed over time among a group of 27 individuals who smoked menthol cigarettes at our safety-net hospital. In a convergent mixed methods study, we administered questionnaires and interviews simultaneously at two timepoints: 1 month pre-ban and 6 months post-ban. Pre-ban, we assessed perceptions of the ban and anticipated smoking behaviors after the ban. Post-ban, we assessed participants’ actual smoking behaviors and elicited suggestions to avoid unintended consequences that might undermine intended policy effects. Several respondents perceived the Massachusetts ban as positive because it could promote smoking cessation, prevent youth initiation, and mitigate unfair targeting of socioeconomically disadvantaged populations. Others perceived the ban as an overreach of government policy, financially motivated, and unfairly targeting the Black community. Many continued to smoke menthol cigarettes obtained outside Massachusetts. Individuals suggested promoting tobacco treatment for people affected by the ban and a national ban to circumvent out-of-state purchasing of menthol cigarettes. Our findings suggest that in order to be most effective, healthcare systems must promote tobacco treatment and ensure that treatment is accessible to all individuals affected by the ban.
Genotoxic Potential of Thymol on Honey Bee DNA in the Comet Assay
Authors: Glavinić Uroš , Rajković Milan , Ristanić Marko , Stevanović Jevrosima , Vejnović Branislav , Djelić Ninoslav , Stanimirović Zoran
Published: May 2023

Thymol is a natural essential oil derived from the plant Thymus vulgaris L. It is known to be beneficial for human and animal health and has been used in beekeeping practice against Varroa mite for years. In this study, the genotoxic and antigenotoxic potential of thymol were evaluated on the honey bee (Apis mellifera L.) continuous cell line AmE-711 for the first time. Using the Comet assay, three increasing concentrations (10, 100, and 1000 µg/mL) of thymol were tested. Negative control (non-treated cells) and positive control (cells treated with 100 µM H2O2) were also included. The absence of thymol cytotoxicity was confirmed with the Trypan blue exclusion test. Thymol in the concentration of 10 µg/mL did not increase DNA damage in AmE-711 honey bee cells, while 100 and 1000 µg/mL concentrations showed genotoxic effects. For testing the antigenotoxic effect, all concentrations of thymol were mixed and incubated with H2O2. The antigenotoxic effect against was absent at all concentrations (10, 100, 1000 μg/mL) tested. Moreover, thymol enhanced the H2O2-induced DNA migration in the Comet assay. The obtained results indicate genotoxic effects of thymol on cultured honey bee cells suggesting its careful application in beekeeping practice to avoid possible negative effects on honey bees.
Single Sporadic Deceleration during Reactive Nonstress Test—Clinical Significance and Risk for Cesarean Delivery
Authors: Weinberger Hila , Nekave Shlomit , Hallak Mordechai , Naeh Amir , Gabbay-Benziv Rinat
Published: May 2023

Objective: Evidence regarding the clinical significance of a single sporadic variable deceleration (SSD) in reactive non-stress test (NST) is scarce, and optimal management has yet to be established. We aim to evaluate whether SSD during a reactive NST at term is associated with a higher risk for fetal heart rate decelerations during labor and the need for intervention. Methods: This was a retrospective, case-control study of singleton term pregnancies at one university-affiliated medical center in 2018. The study group consisted of all pregnancies with an SSD in an otherwise reactive NST. For each case, two consecutive pregnancies without SSD were matched in a 1:2 ratio. The primary outcome was the rate of cesarean delivery (CD) due to non-reassuring fetal heart rate monitoring (NRFHRM). Results: 84 women with an SSD were compared to 168 controls. SSD during antenatal fetal surveillance did not increase the rate of CD overall or for NRFHRM (17.9% vs. 13.7% and 10.7% vs. 7.7%, respectively, p > 0.05). Rates of assisted deliveries and maternal and neonatal complications were similar between the groups. Conclusions: SSD during a reactive NST in term pregnancies is not associated with an increased risk for adverse perinatal outcomes. SSD should not necessarily require induction of labor, and expectant management is a reasonable alternative.
Local Gentamicin Fixation with Sprayed Fibrin—An In Vivo Animal Study Reveals New Options to Treat Soft Tissue Infections
Authors: Kejwal Meike B. , Verboket René D. , Sommer Katharina , Dust Fabian , Thomas Dominique , Störmann Philipp , Frank Johannes , Henrich Dirk , Marzi Ingo , Janko Maren C.
Published: May 2023

For acute and chronic soft tissue infections, radical surgical debridement is required and is considered the gold standard, along with its immediate systemic antibiotic therapy. Treatment with local antibiotics and/or antibiotic-containing materials is commonly used as an additional tool in clinical practice. Spraying with fibrin and antibiotics is a newer technique that has been studied for some antibiotics. However, for gentamicin, data are not yet available on absorption, optimal application, antibiotic fate at the site and transfer of antibiotic into the blood. In an animal study involving 29 Sprague Dawley rats, 116 back wounds were sprayed with gentamicin using either gentamicin alone or one of two possible spray combinations of gentamicin and fibrin. Simultaneous application of gentamicin and fibrin via a spray system to soft tissue wounds resulted in significant antibiotic concentration over a long period of time. The technique is easy and cost-effective. The systemic crossover was significantly minimized in our study, which may have led to fewer side effects in patients. These results could lead to an improvement in local antibiotic therapy.
Effects and Usefulness of Inspiratory Muscle Training Load in Patients with Advanced Lung Cancer with Dyspnea
Authors: Sakai Yasunari , Yamaga Takayoshi , Yamamoto Shuhei , Matsumori Keiji , Ichiyama Takashi , Hanaoka Masayuki , Ikegami Shota , Horiuchi Hiroshi
Published: May 2023

Background: Patients with advanced lung cancer tend to experience dyspnea. Pulmonary rehabilitation has been reported as a method for relieving dyspnea. However, exercise therapy imposes a high burden on patients, and it is difficult to sustain in many cases. Inspiratory muscle training (IMT) imposes a relatively low burden on patients with advanced lung cancer; however, its benefits have not been demonstrated. Methods: We retrospectively analyzed 71 patients who were hospitalized for medical treatment. The participants were divided into an exercise therapy group and an IMT load + exercise therapy group. Changes in maximal inspiratory pressure (MIP) and dyspnea were examined using a two-way repeated measures analysis of variance. Results: MIP variations significantly increase in the IMT load group, with significant differences between baseline and week 1, between week 1 and week 2, and between baseline and week 2. The analysis also showed that the variations in dyspnea decreased in the IMT load + exercise therapy group with significant differences between baseline and week 1 and between baseline and week 2. Conclusions: The results show that IMT is useful and has a high persistence rate in patients with advanced lung cancer who present dyspnea and cannot perform high-intensity exercise therapy.
Cells and Materials for Cardiac Repair and Regeneration
Authors: Alhejailan Reem , Garoffolo Gloria , Raveendran Vineesh , Pesce Maurizio
Published: May 2023

After more than 20 years following the introduction of regenerative medicine to address the problem of cardiac diseases, still questions arise as to the best cell types and materials to use to obtain effective clinical translation. Now that it is definitively clear that the heart does not have a consistent reservoir of stem cells that could give rise to new myocytes, and that there are cells that could contribute, at most, with their pro-angiogenic or immunomodulatory potential, there is fierce debate on what will emerge as the winning strategy. In this regard, new developments in somatic cells’ reprogramming, material science and cell biophysics may be of help, not only for protecting the heart from the deleterious consequences of aging, ischemia and metabolic disorders, but also to boost an endogenous regeneration potential that seems to be lost in the adulthood of the human heart.
The Clinical Potential of 3D-Printed Crowns Reinforced with Zirconia and Glass Silica Microfillers
Authors: Alshamrani Abdullah , Alhotan Abdulaziz , Owais Ahmed , Ellakwa Ayman
Published: May 2023

The development of 3D-printed crown resin materials with improved mechanical and physical properties is an area of growing interest in dentistry. This study aimed to develop a 3D-printed crown resin material modified with zirconia glass (ZG) and glass silica (GS) microfillers to enhance overall mechanical and physical properties. A total of 125 specimens were created and divided into five groups: control unmodified resin, 5% either ZG or GS reinforced 3D-printed resin, and 10% either ZG or GS reinforced 3D-printed resin. The fracture resistance, surface roughness, and translucency parameter were measured, and fractured crowns were studied under a scanning electron microscope. The results showed that 3D-printed parts that were strengthened with ZG and GS microfillers demonstrated comparable mechanical performance to unmodified crown resin but resulted in greater surface roughness, and only the group that contained 5% ZG showed an increase in translucency. However, it should be noted that increased surface roughness may impact the aesthetics of the crowns, and further optimisation of microfillers concentrations may be necessary. These findings suggest that the newly developed dental-based resins that incorporate microfillers could be suitable for clinical applications, but further studies are necessary to optimise the nanoparticle concentrations and investigate their long-term clinical outcomes.
A Smart Risk Assessment Tool for Decision Support during Ship Evacuation
Authors: Ventikos Nikolaos P. , Koimtzoglou Alexandros , Louzis Konstantinos , Themelis Nikolaos , Koimtzoglou Marios-Anestis
Published: May 2023

In case of a ship emergency situation and during its evolvement that might result in an evacuation, the master and the bridge command team of a ship have to continuously assess risk. This is a very complex procedure, as crucial decisions concerning safety are made under time pressure. The use of a decision-support tool would have a positive effect on their performance, resulting in an improvement in the way ships are evacuated. The purpose of this paper is to present the PALAEMON smart risk assessment platform (SRAP). SRAP is a real-time risk assessment platform developed to assist the decision-making process of the master and bridge command team of a ship regarding the evacuation process. Its purpose is to provide decision support for the following aspects: (1) the decision to sound the general alarm (GA) following an accident, (2) monitoring the progress of the mustering process in order to take any additional actions, and (3) the decision to abandon the ship or not. SRAP dynamically assesses the risk to the safety of the passengers and crew members in the different phases of the evacuation process, so one model in the form Bayesian networks (BNs) was developed for each stage of the evacuation process. The results of a case study that was implemented reflect how various parameters such as injuries, congestion, and the functionality of the ship’s systems affect the outcome of each model.
Dietary Wheat Gluten Alters the Gut Microbiome and Plasma Taurine Levels in European Sea Bass (Dicentrarchus labrax)
Authors: Larkin Mary E. M. , Place Allen R.
Published: May 2023

Incorporating environmentally sustainable plant-based protein sources into aquafeeds is a priority for the aquaculture industry. Wheat gluten as a plant protein source has been successfully integrated into feeds for several fish species. However, unique nutritional requirements and the potential for intolerances necessitate the evaluation of plant-based diets by species. Previous work by our laboratory indicated that wheat gluten at less than 4% inclusion in a compound feed had a negative impact on growth and survival rate in juvenile cobia (Rachycentron canadum). In the current study, we evaluated the effects of wheat gluten inclusion in a plant-based diet in juvenile European sea bass (Dicentrarchus labrax). No major differences were observed in terms of growth rate, plasma biochemical parameters, detectable induction of plasma IgM, IgT, or factors capable of binding gliadin in response to the inclusion of 4% dietary wheat gluten. However, plasma levels of taurine doubled in the fish fed wheat gluten, and there were considerable changes to the intestinal microbiome. Despite these measurable changes, the data suggest that dietary inclusion of 4% wheat gluten is well tolerated by juvenile European sea bass in a plant-based feed formulation.
Investigating the Reliability of the Location Transmitted by V-Pass Terminals: Prompt Rescue of Fishing Vessels
Authors: Park Cheor-Hong , Jung Bong-Kyu , Choi Won-Sam
Published: May 2023

Fishing boats are equipped to quickly rescue ships and save lives in the event of an incident at sea; therefore, determination of the incident location is imperative for a swift response. According to the 2021 marine accidents by ship use statistics, fishing and non-fishing boats accounted for 64.6 and 35.4%, respectively, of the total 3053 ships involved in an accident. In addition to V-pass and the Automatic Identification System (AIS), several other types of terminals exist; however, approximately 91% of all registered fishing boats use V-pass terminals. Therefore, it is essential to know the exact location of fishing boats. However, little research has been conducted on V-pass equipment. Therefore, in this study, marine experiments were conducted using V-pass and AIS terminals that are mainly used in fishing boats. To determine the exact location of an incident and rapidly respond and rescue, this study compared the data saved in the terminals with the data received by the Vessel Traffic Service center. In the event of a maritime incident, the radio shadow areas and causes of the error in the location transmitter must be investigated to quickly rescue the fishing boat and to determine the root cause of the incident, respectively.
Efficacy and Safety of Axiostat® Hemostatic Dressing in Aiding Manual Compression Closure of the Femoral Arterial Access Site in Patients Undergoing Endovascular Treatments: A Preliminary Clinical Experience in Two Centers
Authors: Minici Roberto , Serra Raffaele , Maglia Claudio , Guzzardi Giuseppe , Spinetta Marco , Fontana Federico , Venturini Massimo , Laganà Domenico
Published: May 2023

Background: Hemostasis of the femoral arterial access site by manual compression or a vascular closure device is critical to the safe completion of any endovascular procedure. Previous investigations evaluated the hemostatic efficacy at the radial access site of some chitosan-based hemostatic pads. This study aims to assess the efficacy and safety of a new chitosan-based hemostatic dressing, namely Axiostat®, in aiding manual compression closure of the femoral arterial access site in patients undergoing endovascular treatments. Furthermore, the outcomes were compared with evidence on manual compression alone and vascular closure devices. Methods: This investigation is a two-center retrospective analysis of 120 consecutive patients who had undergone, from July 2022 to February 2023, manual compression closure of the femoral arterial access site aided by the Axiostat® hemostatic dressing. Endovascular procedures performed with introducer sheaths ranging from 4 Fr to 8 Fr were evaluated. Results: Primary technical success was achieved in 110 (91.7%) patients, with adequate hemostasis obtained in all cases of prolonged manual compression requirements. The mean time-to-hemostasis and time-to-ambulation were 8.9 (±3.9) and 462 (±199) minutes, respectively. Clinical success was achieved in 113 (94.2%) patients, with bleeding-related complications noted in 7 (5.8%) patients. Conclusions: Manual compression aided by the Axiostat® hemostatic dressing is effective and safe in achieving hemostasis of the femoral arterial access site in patients undergoing endovascular treatment with a 4–8 Fr introducer sheath.
Therapeutic Drug Monitoring in Arterial Hypertension
Authors: Seleznev Sergey , Shchulkin Alexey , Mylnikov Pavel , Yakusheva Elena , Nikulina Natalia
Published: May 2023

(1) Background: This study was planned to assess the concentration of antihypertensive drugs (AHD) in the blood serum in patients with controlled and uncontrolled arterial hypertension (AH). (2) Methods: We assessed 46 patients with AH. Based on the results of 24 h blood pressure monitoring (ABPM), the patients were randomized into two groups. The first group consisted of the patients with controlled AH; the second group consisted of the patients with uncontrolled AH. Venous blood was taken in both groups of patients in the morning before and 2 h after taking drugs to assess the concentration of lisinopril, amlodipine, valsartan, and indapamide. (3) Results. The first group included 27 patients, and the second group 19 patients. In patients with uncontrolled AH, the median concentrations of lisinopril, indapamide, amlodipine, and valsartan before and after taking the drugs did not differ from patients who reached the target BP values. (p > 0.05). In some patients with uncontrolled and controlled (shown for the first time) AH the concentration of AHD was below the limit of quantitative determination. (4) Conclusions. The obtained results indicate that the pharmacokinetics of AHD, apparently, does not play a significant role in the development of ineffectiveness of the ongoing therapy for AH. Therapeutic drug monitoring can be used to test adherence to the treatment.
Tissue Oximetry Changes during Postoperative Dangling in Lower Extremity Free Flap Reconstruction: A Pilot Study
Authors: Lindelauf Anouk A. M. A. , van Rooij Joep A. F. , Hartveld Loes , van der Hulst René R. W. J. , Weerwind Patrick W. , Schols Rutger M.
Published: May 2023

Background: Lower extremity free flap dangling protocols are still widely practiced, despite a paucity of evidence for their use. This pilot study investigates the use of tissue oximetry to provide further insight into the physiological effect of postoperative dangling in lower limb free flap transfer. Methods: Ten patients undergoing lower extremity free flap reconstruction were included in this study. Free flap tissue oxygen saturation (StO2) was continuously measured using non-invasive near-infrared spectroscopy. Measurements were performed on the free flap and contralateral limb during dangling from postoperative day (POD) 7 until 11, according to the local dangling protocol. Results: StO2 values measured in the free flap diminished to 70 ± 13.7% during dangling. This minimum StO2 was reached significantly later, and correspondingly the area under the curve (AUC) was significantly larger on POD 11 compared to the start of the dangling protocol on POD 7, reflecting an improving free flap microvascular reactivity. The dangling slope was equal between the free flap and contralateral leg. The reperfusion slope was significantly flatter on POD 7 compared to the other PODs (p < 0.001). Thereafter, no significant differences between PODs were observed. Patients with a history of smoking had significantly lower tissue oximetry values compared to non-smokers. Conclusions: The application of tissue oximetry during dangling provides further insight into the physiological effect (i.e., changes in microcirculatory function) of the free flap of the reconstructed lower extremity. This information could potentially be useful to either revise or disrupt the use of such dangling protocols.
Diversity of Antimicrobial Peptides in Silkworm
Authors: Makwana Pooja , Rahul Kamidi , Ito Katsuhiko , Subhadra Bindu
Published: May 2023

Antimicrobial resistance is a phenomenon that the present-day world is witnessing that poses a serious threat to global health. The decline in the development of novel therapeutics over the last couple of decades has exacerbated the situation further. In this scenario, the pursuit of new alternative therapeutics to commonly used antibiotics has gained predominance amongst researchers across the world. Antimicrobial peptides (AMPs) from natural sources have drawn significant interest in the recent years as promising pharmacological substitutes over the conventional antibiotics. The most notable advantage of AMPs is that microorganisms cannot develop resistance to them. Insects represent one of the potential sources of AMPs, which are synthesized as part of an innate immune defence against invading pathogens. AMPs from different insects have been extensively studied, and silkworm is one of them. Diverse classes of AMPs (including attacins, cecropins, defensins, enbocins, gloverins, lebocins and moricins) were identified from silkworm that exhibit antimicrobial property against bacteria, fungi and viruses, indicating their potential therapeutic benefits. This review briefs about the immune responses of silkworm to invading pathogens, the isolation of AMPs from silkworms, AMPs reported in silkworms and their activity against various microorganisms.
3D Surface Scanning—A Novel Protocol to Characterize Virtual Nickel–Titanium Endodontic Instruments
Authors: Martins Jorge N. R. , Pinto Ricardo , Silva Emmanuel J. N. L. , Simões-Carvalho Marco , Marques Duarte , Martins Rui F. , Versiani Marco A.
Published: May 2023

The nickel–titanium (NiTi) instruments’ geometry plays an important role in their performance and behavior. The present assessment intends to validate and test the applicability of a 3D surface scanning method using a high-resolution laboratory-based optical scanner to create reliable virtual models of NiTi instruments. Sixteen instruments were scanned using a 12-megapixel optical 3D scanner, and methodological validation was performed by comparing quantitative and qualitative measurements of specific dimensions and identifying some geometric features of the 3D models with images obtained through scanning electron microscopy. Additionally, the reproducibility of the method was assessed by calculating 2D and 3D parameters of three different instruments twice. The quality of the 3D models created by two different optical scanners and a micro-CT device was compared. The 3D surface scanning method using the high-resolution laboratory-based optical scanner allowed for the creation of reliable and precise virtual models of different NiTi instruments with discrepancies varying from 0.0002 to 0.0182 mm. The reproducibility of measurements performed with this method was high, and the acquired virtual models were adequate for use in in silico experiments, as well as for commercial or educational purposes. The quality of the 3D model obtained using the high-resolution optical scanner was superior to that acquired by micro-CT technology. The ability to superimpose virtual models of scanned instruments and apply them in Finite Element Analysis and educational purposes was also demonstrated.
Uniaxial Rotational Molding of Bio-Based Low-Density Polyethylene Filled with Black Tea Waste
Authors: Aniśko Joanna , Barczewski Mateusz
Published: May 2023

In this paper, the possibility of obtaining uniaxially rotomolded composite parts was discussed. The used matrix was bio-based low-density polyethylene (bioLDPE) filled with black tea waste (BTW) to prevent the thermooxidation of samples during processing. In rotational molding technology, the material is held at an elevated temperature in a molten state for a relatively long time, which can result in polymer oxidation. The Fourier transform infrared spectroscopy (FTIR) shows that adding 10 wt% of black tea waste has not led to the formation of carbonyl compounds in polyethylene, and adding 5 wt% and above prevents the appearance of the C–O stretching band connected with degradation of LDPE. The rheological analysis proved the stabilizing effect of black tea waste on the polyethylene matrix. The same temperature conditions of rotational molding did not change the chemical composition of black tea but slightly influenced the antioxidant activity of methanolic extracts; the detected changes suggest degradation is a color change, and the total color change parameter (ΔE) is 25. The oxidation level of unstabilized polyethylene measured using the carbonyl index exceeds 1.5 and gradually decreases with the addition of BTW. The BTW filler did not influence the melting properties of bioLDPE; the melting and crystallization temperature remained stable. The addition of BTW deteriorates the composite mechanical performance, including Young modulus and tensile strength, compared to the neat bioLDPE.
Effect of Deposition Temperature on Long-Term Residual Stress Evolution of Au Films
Authors: Zhou Shujun , Wu Wei , Yang Yilun , Huang Xiao
Published: May 2023

To increase the residual stress stability of Au films while reducing the residual stress level, the effect of deposition temperature on long-term residual stress evolution of Au films under different conditions were studied. Au films with a thickness of 360 nm were deposited using e-beam evaporation on fused silica under different temperatures. Observations and comparisons were made of the microstructures of Au films deposited under different temperatures. Results showed that by increasing the deposition temperature, a more compact microstructure of Au film was obtained, which was manifested in increased grain size and reduced grain-boundary voids. After deposition, a combined process consisting of natural placement and 80 °C thermal holding was conducted on the Au films, and the residual stresses were monitored using the curvature-based technique. Results showed that the initial tensile residual stress of the as-deposited film decreased with the deposition temperature. The Au films with higher deposition temperatures showed better residual stress stability, maintaining low stress levels in the subsequent long-term combination of natural placement and thermal holding. The mechanism was discussed based on the differences in microstructure. Comparisons were made between post-deposition annealing and increased deposition temperature.
Combustion Synthesis of Magnesium-Aluminum Oxynitride MgAlON with Tunable Composition
Authors: Akopdzhanyan Tigran , Abzalov Danil , Moskovskikh Dmitry , Abedi Mohammad , Romanovski Valentin
Published: May 2023

Magnesium-aluminum oxynitride MgAlON has garnered significant attention in recent years due to its unique properties and potential applications. Herein, we report a systematic study on the synthesis of MgAlON with tunable composition by employing the combustion method. The Al/Al2O3/MgO mixture was combusted in nitrogen gas, and the effects of Al nitriding and oxidation by Mg(ClO4)2 on the exothermicity of the mixture, combustion kinetics, and phase composition of combustion products were investigated. Our results demonstrate that the MgAlON lattice parameter can be controlled by varying the AlON/MgAl2O4 ratio in the mixture, which corresponds to the MgO content in the combustion products. This work provides a new pathway for tailoring the properties of MgAlON, which may have significant implications in various technological applications. In particular, we reveal the dependence of the MgAlON lattice parameter on the AlON/MgAl2O4 ratio. The limitation of the combustion temperature by 1650 °C resulted in obtaining submicron powders with a specific surface area of about 3.8 m/g2.
Fucoidan-Containing, Low-Adhesive Siloxane Coatings for Medical Applications: Inhibition of Bacterial Growth and Biofilm Development
Authors: Vladkova Todorka G. , Staneva Anna D. , Avramova Ivalina A. , Ivanova Iliana A. , Gospodinova Dilyana N.
Published: May 2023

The deposition of low-adhesive siloxane coatings is a current trend for the non-toxic control of bacterial growth and biofilm formation. Total elimination of biofilm formation has not been reported so far. The aim of this investigation was to study the ability of a non-toxic, natural, biologically active substance, such as fucoidan, to inhibit bacterial growth on similar medical coatings. The fucoidan amount was varied, and its impact on the bioadhesion-influencing surface characteristics, as well as on bacterial cell growth, was investigated. The inclusion of up to 3–4 wt.% brown algae-derived fucoidan in the coatings increases their inhibitory effect, more significantly on the Gram-positive bacterium S. aureus than on the Gram-negative bacterium Escherichia coli. The biological activity of the studied siloxane coatings was ascribed to the formation of a low-adhesive, biologically active surface top layer consisting of siloxane oil and dispersed water-soluble fucoidan particles. This is the first report on the antibacterial activity of fucoidan-containing medical siloxane coatings. The experimental results give reason to expect that relevantly selected, natural biologically active substances can be efficient in the non-toxic control of bacterial growth on medical devices and, as a result, medical device-associated infections.
Effects of Different Materials on Residual Stress Fields of Blade Damaged by Foreign Objects
Authors: Yin Wangtian , Liu Yongbao , He Xing , Li Hongsong
Published: May 2023

Foreign object damage (FOD) is a common mode of failure in high-speed rotating machinery, such as aircraft engines. Therefore, research on FOD is crucial for ensuring blade integrity. FOD induces residual stress on the surface and within the blade, impacting its fatigue strength and service life. Therefore, this paper utilizes material parameters determined by existing experiments, based on the Johnson–Cook (J-C) constitutive model, to numerically simulate impact damage inflicted on specimens, compare and analyze the residual stress distribution of impact pits, and investigate the influence law of foreign object characteristics on blade residual stress. TC4 titanium alloy, 2A12 aluminum alloy, and Q235 steel were selected as foreign objects, and dynamic numerical simulations of the blade impact process were performed to explore the effects of different types of metal foreign objects. This study analyzes the influence of different materials and foreign objects on the residual stress generated by blade impact through numerical simulation, examining the distribution of residual stress in different directions. The findings indicate that the generated residual stress increases with the density of the materials. Additionally, the geometry of the impact notch is also influenced by the density difference between the impact material and the blade. The distribution of the residual stress field reveals that the maximum residual tensile stress in the blade is related to the density ratio, and the residual tensile stress in the axial and circumferential direction is relatively large. It is important to note that a significant residual tensile stress has a detrimental effect on the fatigue strength.
Influence of Al Addition on the Microstructure and Mechanical Properties of Mg-Zn-Sn-Mn-Ca Alloys
Authors: Yan Shujuan , Hou Caihong , Zhang Angui , Qi Fugang
Published: May 2023

The effects of Al addition on the microstructure and mechanical properties of Mg-Zn-Sn-Mn-Ca alloys are studied in this paper. It was found that the Mg-6Sn-4Zn-1Mn-0.2Ca-xAl (ZTM641-0.2Ca-xAl, x = 0, 0.5, 1, 2 wt.%; hereafter, all compositions are in weight percent unless stated otherwise) alloys have α-Mg, Mg2Sn, Mg7Zn3, MgZn, α-Mn, CaMgSn, AlMn, Mg32(Al,Zn)49 phases. The grain is also refined when the Al element is added, and the angular-block AlMn phases are formed in the alloys. For the ZTM641-0.2Ca-xAl alloy, the higher Al content is beneficial to elongation, and the double-aged ZTM641-0.2Ca-2Al alloy has the highest elongation, which is 13.2%. The higher Al content enhances the high-temperature strength for the as-extruded ZTM641-0.2Ca alloy; overall, the as-extruded ZTM641-0.2Ca-2Al alloy has the best performance; that is, the tensile strength and yield strength of the ZTM641-0.2Ca-2Al alloy are 159 MPa and 132 MPa at 150 °C, and 103 MPa and 90 MPa at 200 °C, respectively.
Co-Pyrolysis for Pine Sawdust with Potassium Chloride: Insight into Interactions and Assisting Biochar Graphitization
Authors: Xie Linen , Wang Liangcai , Zhou Jianbin , Ma Huanhuan
Published: May 2023

This effort aimed to explore the activation and catalytic graphitization mechanisms of non-toxic salts in converting biomass to biochar from the perspective of pyrolysis kinetics using renewable biomass as feedstock. Consequently, thermogravimetric analysis (TGA) was used to monitor the thermal behaviors of the pine sawdust (PS) and PS/KCl blends. The model-free integration methods and master plots were used to obtain the activation energy (E) values and reaction models, respectively. Further, the pre-exponential factor (A), enthalpy (ΔH), Gibbs free energy (ΔG), entropy (ΔS), and graphitization were evaluated. When the KCl content was above 50%, the presence of KCl decreased the resistance to biochar deposition. In addition, the differences in the dominant reaction mechanisms of the samples were not significant at low (α ≤ 0.5) and high (α ≥ 0.5) conversion rates. Interestingly, the lnA value showed a linearly positive correlation with the E values. The PS and PS/KCl blends possessed positive ΔG and ΔH values, and KCl was able to assist biochar graphitization. Encouragingly, the co-pyrolysis of the PS/KCl blends allows us to target-tune the yield of the three-phase product during biomass pyrolysis.
Adjacent Vertex Distinguishing Coloring of Fuzzy Graphs
Authors: Gong Zengtai , Zhang Chen
Published: May 2023

In this paper, we consider the adjacent vertex distinguishing proper edge coloring (for short, AVDPEC) and the adjacent vertex distinguishing total coloring (for short, AVDTC) of a fuzzy graph. Firstly, this paper describes the development process, the application areas, and the existing review research of fuzzy graphs and adjacent vertex distinguishing coloring of crisp graphs. Secondly, we briefly introduce the coloring theory of crisp graphs and the related theoretical basis of fuzzy graphs, and add some new classes of fuzzy graphs. Then, based on the α-cuts of fuzzy graphs and distance functions, we give two definitions of the AVDPEC of fuzzy graphs, respectively. A lower bound on the chromatic number of the AVDPEC of a fuzzy graph is obtained. With examples, we show that some results of the AVDPEC of a crisp graph do not carry over to our set up; the adjacent vertex distinguishing chromatic number of the fuzzy graph is different from the general chromatic number of a fuzzy graph. We also give a simple algorithm to construct a (d,f)-extended AVDPEC for fuzzy graphs. After that, in a similar way, two definitions of the AVDTC of fuzzy graphs are discussed. Finally, the future research directions of distinguishing coloring of fuzzy graphs are given.
A Fully Completed Spherical Fuzzy Data-Driven Model for Analyzing Employee Satisfaction in Logistics Service Industry
Authors: Nguyen Phi-Hung
Published: May 2023

This study proposes a two-stage MCDM model that combines Delphi and decision-making trial and evaluation laboratory methods based on spherical fuzzy sets (SF-Delphi and SF-DEMATEL) to analyze the motivation and demotivation factors affecting employee satisfaction in the Vietnamese logistics service industry. In the first stage, the SF-Delphi approach is used to gather expert opinions and develop consensus on the significance of criteria. In the second stage, the SF-DEMATEL technique explores causal linkages between the criteria and identifies root causes of the issues. Based on a comprehensive literature review and feedback from 40 experts, this study identified crucial factors affecting employee satisfaction related to both motivation and demotivation aspects. The findings of this study provide recommendations for managers to improve employee satisfaction, such as establishing clear and detailed wage and bonus rules, offering training courses, developing a positive work culture, recognizing employee efforts, and addressing poor treatment by supervisors and inadequate leadership support. Furthermore, the proposed model accurately identifies essential elements, represents uncertainty, adapts to various contexts, has resilience and accuracy, and has practical implications for mitigating demotivating factors and enhancing motivation, thereby positively influencing employee satisfaction in the logistics service industry.
A Systematic Review of Consensus Mechanisms in Blockchain
Authors: Zhou Sisi , Li Kuanching , Xiao Lijun , Cai Jiahong , Liang Wei , Castiglione Arcangelo
Published: May 2023

Since the birth of Bitcoin, blockchain has shifted from a critical cryptocurrency technology to an enabling technology. Due to its immutability and trustworthiness, blockchain has revolutionized many fields requiring credibility and high-quality data for decision making. Particularly in business intelligence and business process management, users can use blockchain to build their blockchain-enabled collaboration and data-sharing ecosystem with their partners. In this paper, we present the development process of blockchain and consensus mechanisms, where important blockchain consensus mechanisms are introduced. The consensus mechanism is the kernel among various blockchain components to ensure security and performance. Again, we present a comparison of these consensus mechanisms from different perspectives. We take the blockchain-enabling business as an example and analyze the relationship between blockchain and business process characteristics and the ideas and principles for selecting consensus mechanisms. Finally, we describe the differences and connections among many consensus mechanisms while laying a foundation for selecting appropriate consensus mechanisms for different scenarios and fields of application.
Electrokinetic and Electroconvective Effects in Ternary Electrolyte Near Ion-Selective Microsphere
Authors: Ganchenko Georgy S. , Alekseev Maxim S. , Moroz Ilya A. , Mareev Semyon A. , Shelistov Vladimir S. , Demekhin Evgeny A.
Published: May 2023

The paper presents theoretical and experimental investigations of the behavior of an electrolyte solution with three types of ions near an ion-selective microparticle with electrokinetically and pressure-driven flow. A special experimental cell has been developed for the investigations. An anion-selective spherical particle composed of ion-exchange resin is fixed in the center of the cell. An enriched region with a high salt concentration appears at the anode side of the particle when an electric field is turned on, according to the nonequilibrium electrosmosis behavior. A similar region exists near a flat anion-selective membrane. However, the enriched region near the particle produces a concentration jet that spreads downstream akin to a wake behind an axisymmetrical body. The fluorescent cations of Rhodamine-6G dye are chosen as the third species in the experiments. The ions of Rhodamine-6G have a 10-fold lower diffusion coefficient than the ions of potassium while bearing the same valency. This paper shows that the concentration jet behavior is described accurately enough with the mathematical model of a far axisymmetric wake behind a body in a fluid flow. The third species also forms an enriched jet, but its distribution turns out to be more complex. The concentration of the third species increases in the jet with an increase in pressure gradient. The pressure-driven flow stabilizes the jet, yet electroconvection has been observed near the microparticle for sufficiently strong electric fields. The electrokinetic instability and the electroconvection partially destroy the concentration jet of salt and the third species. The conducted experiments show good qualitative agreement with the numerical simulations. The presented results could be used in future for implementing microdevices based on membrane technology for solving problems of detection and preconcentration, and thus simplifying chemical and medical analyses utilizing the superconcentration phenomenon. Such devices are called membrane sensors, and are actively being studied.
Multi-Response Optimization of Milling Process of Hardened S50C Steel Using SVM-GA Based Method
Authors: Nguyen Thanh-Cong , Tien Dung , Nguyen Ba-Nghien , Hsu Quang-Cherng
Published: May 2023

This study aims to find the optimized parameters for surveying the milling process of S50C steel in a minimum quantity lubrication (MQL) environment using a support vector machine-genetic algorithm (SVM-GA). Based on the experimental matrix designed by the Taguchi method, surface roughness and cutting force data were collected corresponding to each experiment with changes in input parameters such as cutting speed, tooth feed rate, and axial depth of cut, along with changes in two parameters of the minimum lubrication system: flow rates and injection pressure. Through analysis by the SVR-NSGAII method, the study obtained the optimal parameters of cutting and lubricating conditions when prioritizing either surface roughness or focusing on the cutting force; however, the most comprehensive result is believed to be achieved by balancing these two factors. So, when striving for the neutral value of both output parameters, which are surface roughness (µm) and cutting force (N), the optimum parameters including injection pressure (MPa), flow rates (mL/h), cutting speed (m/min), feed rate (mm/tooth), and axial depth of cut (mm) are proposed.