bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of an Increased Particle Size Distribution of Ti-6Al-4V Powders Used for Laser-Based Powder Bed Fusion of Metals
Authors: Ludwig Ina , Kluge Maximilian
Published: June 2024

This study investigates the potential benefits of integrating coarser particle size distributions (PSDs) of 45–106 µm into laser-based powder bed fusion of metals (PBF-LB/M), aiming to reduce costs while maintaining quality standards. Despite the considerable advantages of PBF-LB/M for producing intricate geometries with high precision, the high cost of metal powders remains a barrier to its widespread adoption. By exploring the use of coarser PSDs, particularly from electron beam-based powder bed fusion of metals (PBF-EB/M), significant cost-saving opportunities are identified. Through a comprehensive powder characterization, process analysis, and mechanical property evaluation, this study demonstrates that PBF-LB/M can effectively utilize coarser powders while achieving comparable mechanical properties as those produced with a 20–53 µm PSD. Adaptations to the process parameters enable the successful processing of coarser powders, maintaining high relative density components with minimal porosity. Additionally, market surveys reveal substantial cost differentials between PBF-LB/M and PBF-EB/M powders, indicating a 40% cost reduction potential for the feedstock material by integrating coarser PSDs into PBF-LB/M. Overall, this study provides valuable insights into the economic and technical feasibility of printing with coarser powders in PBF-LB/M, offering promising avenues for cost reduction without compromising quality, thus enhancing competitiveness and the adoption of the technology in manufacturing applications.
Influence of Polypropylene Fiber on Concrete Permeability under Freeze-Thaw Conditions and Mechanical Loading
Authors: Zeng Wei , Wang Weiqi , Wang Qiannan , Li Mengya , Zhang Lining , Tong Yunyun
Published: June 2024

Polypropylene fiber reinforcement is an effective method to enhance the durability of concrete structures. With the increasing public interest in the widespread use of polypropylene fiber reinforced concrete (PFRC), the necessity of evaluating the mechanism of polypropylene fiber (PF) on the permeability of concrete has become prominent. This paper describes the influence of PF on the concrete permeability exposed to freeze-thaw cycles under compressive and tensile stress. The permeability of PFRC under compressive and tensile loads is accurately measured by a specialized permeability setup. The permeability of PFRC under compressive and tensile loads, the volume change of PFRC under compressive load, and the relationship between compressive stress levels at minimum permeability and minimum volume points of PFRC are discussed. The results indicate that the addition of PF adversely affects the permeability of concrete without freeze-thaw damage and cracks. However, it decreases the permeability of concrete specimens exposed to freeze-thaw cycles and cracking. Under compressive load, the permeability of PFRC initially decreases slowly and follows by a significant increase as the compressive stress level increases. This phenomenon correlates with the volume change of the specimen. The compressive stress level of the minimum permeability point and compressive stress level of the minimum volume point of PFRC exhibit a linear correlation, with a fitted proportional function parameter γ ≈ 0.98872. Under tensile load, the permeability of PFRC increases gradually with radial deformation and follows by a significant increase. The strain-permeability curves of PFRC under loading are studied and consist of two stages. In stage I, the permeability of PFRC gradually decreases with the increase of strain under compressive load, while the permeability increases with the increase of strain under tensile load. In stage II, under compressive load, the permeability of PFRC increases with the increase of freeze-thaw cycles, whereas under tensile load, the permeability gradually decreases with the increase of freeze-thaw cycles. The reduction of PF on the permeability of PFRC under tensile load is greater than that under compressive load. In future research, the relationship between strain and permeability of PFRC can be integrated with its constitutive relationship between stress and strain to provide a reference for the application of PF in the waterproofing of concrete structures.
Analytical Modeling of Wave Absorption Performance in Gradient Graphene/Polymer Nanocomposites
Authors: Zhao Qin , Li Fang , Liu Jili
Published: June 2024

Due to the low impedance matching caused by the high dielectric permittivity of graphene, the strong absorption of electromagnetic waves by graphene/polymer nanocomposites is challenging. In this paper, an analytical model for microwave absorption based on Maxwell’s equation and the effective medium theory, considering the interface effect, was constructed to explore the effect of the gradient distribution of graphene in the polymer matrix on its microwave absorption performance. The outcome indicated that the impedance of the composites matched well with the air, and its attenuation ability for electromagnetic waves was obviously improved as the graphene concentration was distributed in a gradient form. For instance, when the thickness of the material is 10 mm, based on the optimal concentration of the homogeneous composites being 0.7 wt%, the graphene concentration range of the gradient composites is set to 0.7–0.9 wt% and distributed in three gradient forms of linear, parabolic, and 0.5 power. The results show that the microwave absorption performance is significantly improved compared with the homogeneous composites. Among them, the effective bandwidth on the 0.5 power distribution is 5.2 GHz, 0.5 GHz higher than that of the homogeneous composites. The minimum reflection loss (RL) is as low as −54.7 dB, which is 26.26 dB lower than that of the homogeneous composites. This paper contributes to the design and application of gradient absorbing structures.
The Impact of Abiotic and Biotic Conditions for Degradation Behaviors of Common Biodegradable Products in Stabilized Composts
Authors: Stegenta-Dąbrowska Sylwia , Korendał Marek , Kochanowicz Maks , Bondos Marcin , Wiercik Paweł , Medyńska-Juraszek Agnieszka , Zafiu Christian
Published: June 2024

This work examines the influence of the degradation behaviors of biotic and abiotic conditions on three types of biodegradable products: cups from PLA and from cellulose, and plates from sugarcane. The main objective of this study was to evaluate if biodegradable products can be degraded in composts that were stabilized by backyard composting. Furthermore, the impact of crucial abiotic parameters (temperature and pH) for the degradation behaviors process was investigated. The changes in the biopolymers were analyzed by FTIR spectroscopy. This work confirmed that abiotic and biotic conditions are important for an effective disintegration of the investigated biodegradable products. Under abiotic conditions, the degradation behaviors of PLA were observable under both tested temperature (38 and 59 °C) conditions, but only at the higher temperature was complete disintegration observed after 6 weeks of incubation in mature compost. Moreover, our research shows that some biodegradable products made from cellulose also need additional attention, especially with respect to incorporated additives, as composting could be altered and optimal conditions in composting may not be achieved. This study shows that the disintegration of biodegradable products is a comprehensive process and requires detailed evaluation during composting. The results also showed that biodegradable products can also be degraded post composting and that microplastic pollution from biodegradable polymers in soil may be removed by simple physical treatments.
The Study of Composite Materials Properties Based on Polymers and Nano-Additives from Industrial Wastes from Kazakhstan
Authors: Sharifov Dzhumakhon , Niyazbekova Rimma , Mirzo Avazi , Shansharova Lazzat , Serekpayeva Mira , Aldabergenova Saule , Ibzhanova Ainur , Machnik Ryszard , Bembenek Michał
Published: June 2024

This research is aimed at studying the properties of polymer anticorrosion coatings based on ED-20 resin widely used in practice and industrial wastes. In this work, three basic types of nanoscale nanofillers were chosen: dispersed particles—microsilica, microspheres obtained at Kazakh enterprises, and carbon nanotubes. Physicochemical research methods were used in the research: a laser analyzer for studying the dispersibility of industrial waste and spectrometric research methods. The properties of materials were investigated by standardized methods. The obtained results show that the introduction of microsilica and microspheres obtained at Kazakhstani enterprises, used as additives, improves both the physical and mechanical properties of epoxy composites compared to the standard (control) material. The results of experiments have shown that the optimal content of additives of microsilica and microspheres provides an improvement in the physical and mechanical properties of epoxy composites in comparison with the standard (control) material. Studies have shown that the introduction of microspheres into ED-20 polymer increases impact toughness. The introduction of microsilica into the matrix contributes to the increase of elastic modulus. Experimental studies of optical properties of samples of carbon composite polymer films based on polystyrene (PS) with additives of carbon nanotubes C60 and C70 and multilayer carbon nanotubes were also carried out. The experimental results obtained for the optical properties of polymer composites based on basic polymers from solid waste and carbon nanotubes showed that the optical properties of polymer composites undergo noticeable changes.
Influence of AWJ Process Parameters on Erosion Groove Formation in Additively Manufactured Stainless Steel
Authors: Vandžura Radoslav , Simkulet Vladimír , Botko František , Geľatko Matúš , Hatala Michal
Published: June 2024

The presented manuscript focuses on the influence of process parameters of abrasive water jet technology on the creation of non-transient erosive grooves. The processed stainless steel SS 316L is additively manufactured using the selective laser melting (SLM) method. Due to the distinct mechanical properties of this material resulting from the production process, the material was machined in two planes according to the direction of the printing layers. The experimental part employed a planned experiment utilizing the DoE (Design of Experiment) method. Experiments aimed at varying process parameters (traverse speed, standoff distance, abrasive mass flow) were conducted at a water pressure of 50 MPa, assessing the parameters’ impact on the removed material and the properties of the resulting non-transient erosion groove. The properties of the erosion groove, such as shape and the material removal (area of erosion groove), were evaluated. The influences of process parameters on the observed parameters were assessed using the analysis of variance (ANOVA) method. Experiment preparation and setup were based on a thorough theoretical analysis of the machining process with the abrasive water jet (AWJ) method. The experiment also highlights the diverse properties of the SS 316L material prepared using the SLM method when machined with AWJ technology.
Identification of Heat Transfer Parameters for Gravity Sand Casting Simulations
Authors: Vergnano Alberto , Facondini Pietro , Morselli Nicolò , Veronesi Paolo , Leali Francesco
Published: June 2024

Gravity sand casting simulations require accurate modelling of heat transfer phenomena to reliably evaluate the expected quality of the produced parts. Average model parameters can be easily retrieved from a validated database. However, these parameters are highly dependent on the specific sand used and the actual forming process in the foundry. Furthermore, the heat transfer from the solidifying alloy to the mould surfaces is not precisely known, so simulation models usually use typical values for overall heat transfer coefficients. Most research works investigate individual parameters, whereas heat transfer phenomena largely arise from their interaction together. Therefore, the present work describes a combined experimental and computational method based on genetic algorithm techniques for determining the most important parameters for heat transfer in a sand mould. The experiments examine both virgin and reused sand, as these are alternatively used in the foundry for mould forming. The density, thermal conductivity, and specific heat capacity of the different sands are identified, along with heat transfer coefficients. The counterproof simulations demonstrate that the standard parameters are quite reliable for virgin sand. However, in the case of reused sand, the identified parameters lead to more reliable results.
On Some General Tornheim-Type Series
Authors: Chen Kwang-Wu
Published: June 2024

In this paper, we solve the open problem posed by Kuba by expressing ∑j,k≥1Hk(u)Hj(v)Hj+k(w)jrks(j+k)t as a linear combination of multiple zeta values. These sums include Tornheim’s double series as a special case. Our approach is based on employing two distinct methods to evaluate the specific integral proposed by Yamamoto, which is associated with the two-poset Hasse diagram. We also provide a new evaluation formula for the general Mordell–Tornheim series and some similar types of double and triple series.
An Improved Unbounded-DP Algorithm for the Unbounded Knapsack Problem with Bounded Coefficients
Authors: Yang Yang
Published: June 2024

Benchmark instances for the unbounded knapsack problem are typically generated according to specific criteria within a given constant range R, and these instances can be referred to as the unbounded knapsack problem with bounded coefficients (UKPB). In order to increase the difficulty of solving these instances, the knapsack capacity C is usually set to a very large value. While current efficient algorithms primarily center on the Fast Fourier Transform (FFT) and (min,+)-convolution method, there is a simpler method worth considering. In this paper, based on the basic Unbounded-DP algorithm, we utilize a recent branch and bound (B&B) result and basic theory of linear Diophantine equation, and propose an improved Unbounded-DP algorithm with time complexity of O(R4) and space complexity of O(R3). Additionally, the algorithm can also solve the All-capacities unbounded knapsack problem within the complexity O(R4+C). In particular, the proof techniques required by the algorithm are primarily covered in the first-year mathematics curriculum, which is convenient for subsequent researchers to grasp.
Adaptive Neural Network Prescribed Time Control for Constrained Multi-Robotics Systems with Parametric Uncertainties
Authors: Tang Ruizhi , Lin Hai , Liu Zheng , Zhou Xiaoyang , Gu Yixiang
Published: June 2024

This study designed an adaptive neural network (NN) control method for a category of multi-robotic systems with parametric uncertainties. In practical engineering applications, systems commonly face design challenges due to uncertainties in their parameters. Especially when a system’s parameters are completely unknown, the unpredictability caused by parametric uncertainties may increase control complexity, and even cause system instability. To address these problems, an adaptive NN compensation mechanism is proposed. Moreover, using backstepping and barrier Lyapunov functions (BLFs), guarantee that state constraints can be ensured. With the aid of the transform function, systems’ convergence speeds were greatly improved. Under the implemented control strategy, the prescribed time control of multi-robotic systems with parametric uncertainties under the prescribed performance was achieved. Finally, the efficacy of the proposed control strategy was verified through the application of several cases.
Purification and Screening of the Antialgal Activity of Seaweed Extracts and a New Glycolipid Derivative against Two Ichthyotoxic Red Tide Microalgae Amphidinium carterae and Karenia mikimotoi
Authors: Sun Yingying , Li Hui , Ma Xiao , Pu Mengxuan , Zhang Yuqi , Dong Zhuohan , He Peicong , Zheng Shiyan
Published: June 2024

Ichthyotoxic red tide is a problem that the world is facing and needs to solve. The use of antialgal compounds from marine macroalgae to suppress ichthyotoxic red tide is considered a promising biological control method. Antialgal substances were screened and isolated from Bangia fusco-purpurea, Gelidium amansii, Gloiopeltis furcate, Hizikia fusifarme, Laminaria japonica, Palmaria palmata, and Sargassum sp. to obtain new materials for the development of algaecides against ichthyotoxic red tide microalgae using bioactivity-guided isolation methods. The fractions of seven macroalgae exhibited selective inhibitory activities against Amphidinium carterae and Karenia mikimotoi, of which the ethyl acetate fractions had the strongest and broadest antialgal activities for the two tested red tide microalgae. Their inhibitory effects on A. carterae and K. mikimotoi were even stronger than that of potassium dichromate, such as ethyl acetate fractions of B. purpurea, H. fusifarme, and Sargassum sp. Thin-layer chromatography and ultraviolet spectroscopy were further carried out to screen the ethyl acetate fraction of Sargassum sp. Finally, a new glycolipid derivative, 2-O-eicosanoyl-3-O-(6-amino-6-deoxy)-β-D-glucopyranosyl-glycerol, was isolated and identified from Sargassum sp., and it was isolated for the first time from marine macroalgae. The significant antialgal effects of 2-O-eicosanoyl-3-O-(6-amino-6-deoxy)-β-D-glucopyranosyl-glycerol on A. carterae and K. mikimotoi were determined.
Innovative Alkanediol-Based Eutectic Solvents for Extracting/Pre-Formulating Dermatologically Valuable Free Fatty Acids from Spirulina and Porphyridium Cakes
Authors: Wils Laura , Yagmur Mervé , Bellin Nicolas , Phelippe Myriam , Chevalley Alia , Bodet Charles , Boudesocque-Delaye Leslie
Published: June 2024

The growing demand for phycobiliproteins from microalgae generates a significant volume of by-products, such as extraction cakes. These cakes are enriched with products of interest for the cosmetics market, namely free fatty acids, particularly polyunsaturated (PUFA). In this work, two cakes, one of spirulina and one of Porphyridium cruentum, were valorized using innovative natural hydrophobic deep eutectic solvents (NaDES) based on alkanediols. The most promising NaDES, as determined by physicochemical properties and screening, are mixtures of alkanediols and fatty acids. These include the mixtures of 1,3-propanediol and octanoic acid (1:5, mol/mol) and 1,3-propanediol and octanoic and decanoic acid (1:3:1, mol/mol). Two extractive processes were implemented: ultrasound-assisted extraction and an innovative mechanical process involving dual asymmetric centrifugation. The second process resulted in the production of extracts significantly enriched in PUFA, ranging from 65 to 220 mg/g dry matter with the two cakes. The extracts and NaDES demonstrated good safety with respect to epidermal keratinocyte viability (>80% at 200 µg/mL). The study of their impact on commensal and pathogenic cutaneous bacteria demonstrated significant effects on the viability of Staphylococcus aureus and Staphylococcus epidermidis (>50% decrease at 200 µg/mL) while preserving Corynebacterium xerosis and Cutibacterium acnes. These results highlight the potential of valorizing these co-products using alkanediol-based NaDES, in a strategy combining an active vector (NaDES) and a growth regulator extract, for the management of cutaneous dysbiosis involving staphylococci.
Isaridin E Protects against Sepsis by Inhibiting Von Willebrand Factor-Induced Endothelial Hyperpermeability and Platelet–Endothelium Interaction
Authors: Liu Yao-Sheng , Chen Wen-Liang , Zeng Yu-Wei , Li Zhi-Hong , Zheng Hao-Lin , Pan Ni , Zhao Li-Yan , Wang Shu , Chen Sen-Hua , Jiang Ming-Hua , Jin Chen-Chen , Mi Yu-Chen , Cai Zhao-Hui , Fang Xin-Zhe , Liu Yong-Jun , Liu Lan , Wang Guan-Lei
Published: June 2024

Endothelial hyperpermeability is pivotal in sepsis-associated multi-organ dysfunction. Increased von Willebrand factor (vWF) plasma levels, stemming from activated platelets and endothelium injury during sepsis, can bind to integrin αvβ3, exacerbating endothelial permeability. Hence, targeting this pathway presents a potential therapeutic avenue for sepsis. Recently, we identified isaridin E (ISE), a marine-derived fungal cyclohexadepsipeptide, as a promising antiplatelet and antithrombotic agent with a low bleeding risk. ISE’s influence on septic mortality and sepsis-induced lung injury in a mouse model of sepsis, induced by caecal ligation and puncture, is investigated in this study. ISE dose-dependently improved survival rates, mitigating lung injury, thrombocytopenia, pulmonary endothelial permeability, and vascular inflammation in the mouse model. ISE markedly curtailed vWF release from activated platelets in septic mice by suppressing vesicle-associated membrane protein 8 and soluble N-ethylmaleide-sensitive factor attachment protein 23 overexpression. Moreover, ISE inhibited healthy human platelet adhesion to cultured lipopolysaccharide (LPS)-stimulated human umbilical vein endothelial cells (HUVECs), thereby significantly decreasing vWF secretion and endothelial hyperpermeability. Using cilengitide, a selective integrin αvβ3 inhibitor, it was found that ISE can improve endothelial hyperpermeability by inhibiting vWF binding to αvβ3. Activation of the integrin αvβ3-FAK/Src pathway likely underlies vWF-induced endothelial dysfunction in sepsis. In conclusion, ISE protects against sepsis by inhibiting endothelial hyperpermeability and platelet-endothelium interactions.
Lichen Planus of the Lip—Case Series and Review of the Literature
Authors: Marcu (Selaru) Corina Andreea , Parlatescu Ioanina , Tovaru Serban , Nicolae Carmen Larisa , Costache Mariana , Tovaru Mihaela
Published: June 2024

Background and Objectives: Lichen planus of the lip (LPL) is a chronic inflammatory condition that resembles actinic cheilitis, discoid lupus erythematosus, graft-versus-host disease, and lichenoid reaction to dental materials or drugs. The purpose of this study was to conduct a literature review on lichen planus lip involvement and to report a retrospective observational study that characterises and explores the clinical, histopathological, and evolution of the lesions in a group of patients with unique involvement of LPL. Materials and Methods: Clinical data of patients diagnosed with LPL was retrieved from the medical charts of the patients referred to the Oral Pathology Department of the “Carol Davila” University of Medicine and Pharmacy. A concurrent electronic literature research was carried out using PubMed and Web of Science from 2003 to 2023. Results: Eleven patients diagnosed with unique LPL were analysed (male/female ratio was 1.75, mean age 63.64 years ± 12.52). All patients presented lesions of the lower lip; the clinical forms were atrophic (six cases) and erosive (five cases), and the histopathological exam confirmed the diagnosis. After topical treatment with corticosteroids, most of the patients had complete remission. The literature review revealed 24 studies (sixteen case reports and eight case series) which comprised 84 patients. Isolated lip involvement was reported in 17 studies, and five articles with concomitant oral lichen planus, while two articles did not mention this criterion. Conclusions: Our study brings new data on isolated lichen planus of the lip that primarily affects the lower lip with predominance in male patients. It was reported worldwide in patients between 22 and 75 years old. Topical corticosteroids were the main treatment prescribed and they usually brought remission of the lesions. Lichen planus of the lip is a challenging diagnosis for oral health practitioner providers as well as for dermatologists.
Prevalence, Predictors, and Outcomes of Pulmonary Hypertension in Patients with Lupus Nephritis
Authors: Chen Sixiu , Guo Junhan , Huang Xiamin , He Wei , Yu Xueqing , Xia Xi , Chen Wei
Published: June 2024

Background and Objectives: This study aimed to assess the prevalence, predictors, and outcomes of pulmonary hypertension (PH) in patients with lupus nephritis (LN). Materials and Methods: Baseline characteristics and clinical outcomes of 387 patients with LN were retrospectively collected from 2007 to 2017. PH was defined as pulmonary artery systolic pressure ≥40 mmHg assessed by resting transthoracic echocardiography. The primary endpoint was all-cause mortality. The secondary endpoint was renal events, defined as the doubling of baseline serum creatinine or end-stage renal disease. Associations between PH and outcomes were analyzed by Cox regression models. Results: A total of 15.3% (59/387) of patients with LN were diagnosed with PH, and the prevalence of PH was higher for patients with an estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m2 compared to those with an eGFR ≥ 30 mL/min/1.73 m2 (31.5% vs. 12.6%). Higher mean arterial pressure, lower hemoglobin, and lower triglyceride levels were associated with greater odds of having PH. After adjusting for relevant confounding variables, PH was independently associated with a higher risk for death (HR: 2.01; 95% CI: 1.01–4.00; p = 0.047) and renal events (HR: 2.07; 95% CI: 1.04–4.12; p = 0.039). Conclusions: PH is an independent risk factor for all-cause mortality and adverse renal outcomes in patients with LN.
Diverse Strategies for Modulating Insulin Resistance: Causal or Consequential Inference on Metabolic Parameters in Treatment-Naïve Subjects with Type 2 Diabetes
Authors: Kutoh Eiji , Kuto Alexandra N. , Okada Rumiko , Akiyama Midori , Kurihara Rumi
Published: June 2024

Bacground and Objectives: The objective of this study is to investigate how different therapies modulating insulin resistance, either causally or consequently, affect metabolic parameters in treatment-naïve subjects with T2DM. Subjects and Methods: A total of 212 subjects were assigned to receive either a tight Japanese diet (n = 65), pioglitazone at doses ranging from 15–30 mg/day (n = 70), or canagliflozin at doses ranging from 50–100 mg/day (n = 77) for a duration of three months. Correlations and changes (Δ) in metabolic parameters relative to insulin resistance were investigated. Results: Across these distinct therapeutic interventions, ΔHOMA-R exhibited significant correlations with ΔFBG and ΔHOMA-B, while demonstrating a negative correlation with baseline HOMA-R. However, other parameters such as ΔHbA1c, ΔBMI, ΔTC, ΔTG, Δnon-HDL-C, or ΔUA displayed varying patterns depending on the treatment regimens. Participants were stratified into two groups based on the median value of ΔHOMA-R: the lower half (X) and upper half (Y). Group X consistently demonstrated more pronounced reductions in FBG compared to Group Y across all treatments, while other parameters including HbA1c, HOMA-B, TC, TG, HDL-C, non-HDL-C, TG/HDL-C ratio, or UA exhibited distinct regulatory responses depending on the treatment administered. Conclusions: These findings suggest that (1) regression to the mean is observed in the changes in insulin resistance across these therapies and (2) the modulation of insulin resistance with these therapies, either causally or consequentially, results in differential effects on glycemic parameters, beta-cell function, specific lipids, body weight, or UA.
Environmental Implications of the Soil-to-Groundwater Migration of Heavy Metals in Mining Area Hotspots
Authors: Vesković Jelena , Onjia Antonije
Published: June 2024

Groundwater contamination was studied at several hotspot sites in the Majdanpek copper mining area (Serbia). These sites include a milling facility, a metallurgical wastewater treatment plant, a heavy vehicle service area, and a waste disposal site. In addition to Cu, high concentrations of As and heavy metals (Cd and Pb) were detected in groundwater and soil at the same sampling points. Mining operations and heavy vehicle transport activities have been identified as the main sources of pollution. The migration of metals from soil to groundwater, expressed as a concentration ratio, were the highest for Co and the lowest for Mn. The environmental implications of groundwater pollution were studied using the heavy metal pollution index (HPI), Nemerov pollution index (NPI), hazard index (HI), and incremental lifetime cancer risk (ILCR). HPI and NPI show the high potential of groundwater to have adverse environmental effects. HPI ranges in the following descending order of metals: Cd > Pb > As > Mn > Ni > Cr > Hg > Cu > Zn. NPI exceeds the threshold of 0.7 in 66.7% of the samples. Potential human exposure to the studied groundwater may cause severe health problems in adults, with HI ranging from 0.61 to 5.45 and ILCR from 1.72 × 10−4 to 1.27 × 10−3. Children were more susceptible to non-carcinogenic risk than adults, with HI ranging from 0.95 to 8.27. However, the results indicated that children were less prone to carcinogenic risks, with ILCR ranging from 5.35 × 10−5 to 3.98 × 10−4. Arsenic is the most contributing element to both risks. This research imposes the need for enhanced groundwater monitoring at hotspots in the mining area and the adoption of remediation plans and measures.
Intra-Individual Variations in How Insulin Sensitivity Responds to Long-Term Exercise: Predictions by Machine Learning Based on Large-Scale Serum Proteomics
Authors: Viken Jonas Krag , Olsen Thomas , Drevon Christian André , Hjorth Marit , Birkeland Kåre Inge , Norheim Frode , Lee-Ødegård Sindre
Published: June 2024

Physical activity is effective for preventing and treating type 2 diabetes, but some individuals do not achieve metabolic benefits from exercise (“non-responders”). We investigated non-responders in terms of insulin sensitivity changes following a 12-week supervised strength and endurance exercise program. We used a hyperinsulinaemic euglycaemic clamp to measure insulin sensitivity among 26 men aged 40–65, categorizing them into non-responders or responders based on their insulin sensitivity change scores. The exercise regimen included VO2max, muscle strength, whole-body MRI scans, muscle and fat biopsies, and serum samples. mRNA sequencing was performed on biopsies and Olink proteomics on serum samples. Non-responders showed more visceral and intramuscular fat and signs of dyslipidaemia and low-grade inflammation at baseline and did not improve in insulin sensitivity following exercise, although they showed gains in VO2max and muscle strength. Impaired IL6-JAK-STAT3 signalling in non-responders was suggested by serum proteomics analysis, and a baseline serum proteomic machine learning (ML) algorithm predicted insulin sensitivity responses with high accuracy, validated across two independent exercise cohorts. The ML model identified 30 serum proteins that could forecast exercise-induced insulin sensitivity changes.
PLC-Based Polymer/Silica Hybrid Inverted Ridge LP11 Mode Rotator
Authors: Liang Jiaqi , Zhang Daming , Lv Xinyu , Zeng Guoyan , Cheng Pai , Yin Yuexin , Sun Xiaoqiang , Wang Fei
Published: June 2024

The mode rotator is an important component in a PLC-based mode-division multiplexing (MDM) system, which is used to implement high-order modes with vertical intensity peaks, such as LP11b mode conversions from LP11a in PLC chips. In this paper, an LP11 mode rotator based on a polymer/silica hybrid inverted ridge waveguide is demonstrated. The proposed mode rotator is composed of an asymmetrical waveguide with a trench. According to the simulation results, the broadband conversion efficiency between the LP11a and LP11b modes is greater than 98.5%, covering the C-band after optimization. The highest mode conversion efficiency (MCE) is 99.2% at 1550 nm. The large fabrication tolerance of the proposed rotator enables its wide application in on-chip MDM systems.
Microgripper Robot with End Electropermanent Magnet Collaborative Actuation
Authors: Zhao Yiqun , Tong Dingwen , Chen Yutan , Chen Qinkai , Wu Zhengnan , Xu Xinmiao , Fan Xinjian , Xie Hui , Yang Zhan
Published: June 2024

Magnetic microgrippers, with their miniaturized size, flexible movement, untethered actuation, and programmable deformation, can perform tasks such as cell manipulation, targeted drug delivery, biopsy, and minimally invasive surgery in hard-to-reach regions. However, common external magnetic-field-driving devices suffer from low efficiency and utilization due to the significant size disparity with magnetic microgrippers. Here, we introduce a microgripper robot (MGR) driven by end electromagnetic and permanent magnet collaboration. The magnetic field generated by the microcoils can be amplified by the permanent magnets and the direction can be controlled by changing the current, allowing for precise control over the opening and closing of the magnetic microgripper and enhancing its operational range. Experimental results demonstrate that the MGR can be flexibly controlled in complex constrained environments and is highly adaptable for manipulating objects. Furthermore, the MGR can achieve planar and antigravity object grasping and transportation within complex simulated human cavity pathways. The MGR’s grasping capabilities can also be extended to specialized tasks, such as circuit connection in confined spaces. The MGR combines the required safety and controllability for in vivo operations, making it suitable for potential clinical applications such as tumor or abnormal tissue sampling and surgical assistance.
Current and Ongoing Developments in Targeting Clostridioides difficile Infection and Recurrence
Authors: Cun Wendy Y. , Keller Paul A. , Pyne Stephen G.
Published: June 2024

Clostridioides difficile is a Gram-positive, spore-forming anaerobic bacterial pathogen that causes severe gastrointestinal infection in humans. This review provides background information on C. difficile infection and the pathogenesis and toxigenicity of C. difficile. The risk factors, causes, and the problem of recurrence of disease and current therapeutic treatments are also discussed. Recent therapeutic developments are reviewed including small molecules that inhibit toxin formation, disrupt the cell membrane, inhibit the sporulation process, and activate the host immune system in cells. Other treatments discussed include faecal microbiota treatment, antibody-based immunotherapies, probiotics, vaccines, and violet-blue light disinfection.
FibroScan® versus Biochemical Scores: A Study of Liver Fibrosis in HIV with HBV Co-Infection
Authors: Lungu Giorgiana Nicoleta , Diaconescu Gheorghe Iulian , Dumitrescu Florentina , Docea Anca Oana , Mitrut Radu , Giubelan Lucian , Zlatian Ovidiu , Mitrut Paul
Published: June 2024

The study aimed to determine liver fibrosis in human immunodeficiency virus (HIV) positive individuals using transient elastography (FibroScan®), Fibrosis-4 (FIB-4) score, and aspartate aminotransferase (AST) to Platelet Ratio Index (APRI) in the HIV Department from Infectious Diseases Hospital “Victor Babeș” Craiova, Romania. Of the analyzed HIV-positive subjects (n = 161), 93 (57.76%) had HIV mono-infection, and 68 (42.24%) had Hepatitis B Virus (HBV) co-infection. The prevalence of advanced liver fibrosis was higher (F2: 11.76% and F3: 13.24%, F4: 4.41%) in the HIV-HBV co-infected group compared to the HIV mono-infected group. The univariate and multivariate analysis identified HBV co-infection (OR = 5.73) male sex (OR = 5.34), serum aspartate amino-transferase levels (Pearson’s rho = 0.273), low platelet count (Pearson’s rho = −0.149) and erythrocyte sedimentation rate (OR = 1.030) as risk factors for the presence of liver fibrosis. Body mass index (OR = 1.08), serum lipid levels (OR = 0.96), viral load at diagnosis (OR = 1.00005), and low CD4+ cell count (OR = 0.977) were also correlated with liver fibrosis. The FIB-4 and APRI scores were strongly correlated with each other. In conclusion, HBV co-infection seems to be a determinant factor for liver fibrosis development in people living with HIV, together with other risk factors.
Distribution and Enrichment of Au, Hg, and Tl in the Lanmuchang Deposit, Guizhou, China
Authors: Li Songtao , Liu Jianzhong , Xia Yong , Wang Zepeng , Yang Chengfu , Xie Zhuojun , Tan Qinping , Zhang Bingqiang
Published: June 2024

Mineralization characterized by Au, Hg, and Tl enrichment is rare, and research on Au, Hg, and Tl mineralization is limited. The Lanmuchang Au–Hg–Tl deposit is located in the “Golden Triangle” of Yunnan, Guizhou, and Guangxi Provinces in China. In this study, we used scanning electron microscopy (SEM), electron microprobe analysis (EPMA), and a Tescan integrated mineral analyzer (TIMA) to analyze the mineral composition and distribution of the different types of ores and identify the occurrence state and enrichment mechanism of ore-forming elements in the Lanmuchang deposit. The results show that the primary ore minerals in the Lanmuchang deposit are pyrite, cinnabar, and lorandite. Cinnabar is the primary carrier of Hg (>90%), and pyrite is the primary carrier of Tl (>60%). Gold, Hg, and Tl primarily occur as solid solutions in hydrothermal pyrite, whereas they primarily occur as nano-scale particles in diagenetic pyrite. The substitution of As for S in hydrothermal pyrite promotes Au enrichment. The coupled substitution of 2Fe2+ ⇔ Tl+ + As3+ may be a significant Tl incorporation mechanism and promotes the occurrence of Hg in pyrite. The As and Se contents and Cu/Au and Co/Ni ratios of the hydrothermal pyrite demonstrate that the ore-forming fluid was mostly in a low-temperature, low-salinity, almost-neutral pH, and nearly reducing environment. The results show that the mineralization of the Lanmuchang deposit is associated with the cooling, oxidation, water–rock interaction, and boiling processes of the ore-forming fluid(s).
A Methodology to Determine Undercutting Height in Block/Panel Caving
Authors: Morales Danko , Castro Raúl , Gómez René
Published: June 2024

The undercutting process is a technique employed to initiate the caving of the ore mass in block caving, achieved by creating a basal cut on the block scheduled to be submerged. The effective execution of the undercutting process involves numerous variables, such as the undercut height and the vertical section’s undercut geometry, whose influence has often been overlooked. This research presents a methodology for determining the undercut height in a post-undercutting scenario, including variables such as the undercut level design, the extraction level design, and the air gap. Integral to this methodology is a parameterization that estimates the undercut height, from which design abacuses can be created to aid the assessment of present and future operations for any block/panel caving operation that employs the post-undercutting variant. Additionally, two examples demonstrate the application of this methodology, revealing how alterations in the dimensions of the crown pillar and drawbells significantly influence the undercut height. The calculation methodology outlined in this document delivers an undercutting height, providing an evaluation methodology for ongoing operations. Consequently, any height exceeding this suggests a conservative approach, potentially offering an opportunity for design improvement and alignment with the described parameters.
Enhancing Efficiency of Dye Sensitized Solar Cells by Coinage Metal Doping of Cyanidin-Silver Trimer Hybrids at TiO2 Support Based on Theoretical Study
Authors: Bužančić Milosavljević Margarita , Perić Bakulić Martina , Sanader Maršić Željka , Mravak Antonija , Bonačić-Koutecký Vlasta
Published: June 2024

Identification of a natural-based sensitizer with optimal stability and efficiency for dye-sensitized solar cell (DSSC) application remains a challenging task. Previously, we proposed a new class of sensitizers based on bio-nano hybrids. These systems composed of natural cyanidin dyes interacting with silver nanoclusters (NCs) have demonstrated enhanced opto-electronic and photovoltaic properties. In this study, we explore the doping of silver nanocluster within a cyanidin-Ag3 hybrid employing Density Functional Theory (DFT) and its time-dependent counterpart (TDDFT). Specifically, we investigate the influence of coinage metal atoms (Au and Cu) on the properties of the cyanidin-Ag3 system. Our findings suggest that cyanidin-Ag2Au and cyanidin-AgAuCu emerge as the most promising candidates for improved light harvesting efficiency, increased two-photon absorption, and strong coupling to the TiO2 surface. These theoretical predictions suggest the viability of replacing larger silver NCs with heterometallic trimers such as Ag2Au or AgAuCu, presenting new avenues for utilizing bio-nano hybrids at the surface for DSSC application.
Advances and Prospects of Nanomaterials for Solid-State Hydrogen Storage
Authors: Xu Yaohui , Li Yuting , Gao Liangjuan , Liu Yitao , Ding Zhao
Published: June 2024

Hydrogen energy, known for its high energy density, environmental friendliness, and renewability, stands out as a promising alternative to fossil fuels. However, its broader application is limited by the challenge of efficient and safe storage. In this context, solid-state hydrogen storage using nanomaterials has emerged as a viable solution to the drawbacks of traditional storage methods. This comprehensive review delves into the recent advancements in nanomaterials for solid-state hydrogen storage, elucidating the fundamental principles and mechanisms, highlighting significant material systems, and exploring the strategies of surface and interface engineering alongside catalytic enhancement. We also address the primary challenges and provide future perspectives on the development of nanomaterial-based hydrogen storage technologies. Key discussions include the role of nanomaterial size effects, surface modifications, nanocomposites, and nanocatalysts in optimizing storage performance.
Relevance of Platinum Underlayer Crystal Quality for the Microstructure and Magnetic Properties of the Heterostructures YbFeO3/Pt/YSZ(111)
Authors: Bauer Sondes , Nergis Berkin , Jin Xiaowei , Horák Lukáš , Schneider Reinhard , Holý Václav , Seemann Klaus , Baumbach Tilo , Ulrich Sven
Published: June 2024

The hexagonal ferrite h-YbFeO3 grown on YSZ(111) by pulsed laser deposition is foreseen as a promising single multiferroic candidate where ferroelectricity and antiferromagnetism coexist for future applications at low temperatures. We studied in detail the microstructure as well as the temperature dependence of the magnetic properties of the devices by comparing the heterostructures grown directly on YSZ(111) (i.e., YbPt_Th0nm) with h-YbFeO3 films deposited on substrates buffered with platinum Pt/YSZ(111) and in dependence on the Pt underlayer film thickness (i.e., YbPt_Th10nm, YbPt_Th40nm, YbPt_Th55nm, and YbPt_Th70nm). The goal was to deeply understand the importance of the crystal quality and morphology of the Pt underlayer for the h-YbFeO3 layer crystal quality, surface morphology, and the resulting physical properties. We demonstrate the relevance of homogeneity, continuity, and hillock formation of the Pt layer for the h-YbFeO3 microstructure in terms of crystal structure, mosaicity, grain boundaries, and defect distribution. The findings of transmission electron microscopy and X-ray diffraction reciprocal space mapping characterization enable us to conclude that an optimum film thickness for the Pt bottom electrode is ThPt = 70 nm, which improves the crystal quality of h-YbFeO3 films grown on Pt-buffered YSZ(111) in comparison with h-YbFeO3 films grown on YSZ(111) (i.e., YbPt_Th0nm). The latter shows a disturbance in the crystal structure, in the up-and-down atomic arrangement of the ferroelectric domains, as well as in the Yb–Fe exchange interactions. Therefore, an enhancement in the remanent and in the total magnetization was obtained at low temperatures below 50 K for h-YbFeO3 films deposited on Pt-buffered substrates Pt/YSZ(111) when the Pt underlayer reached ThPt = 70 nm.
Maternal Synbiotic Supplementation with B. breve M-16V and scGOS/lcFOS Shape Offspring Immune Development and Gut Microbiota at the End of Suckling
Authors: Sáez-Fuertes Laura , Kapravelou Garyfallia , Grases-Pintó Blanca , Bernabeu Manuel , Knipping Karen , Garssen Johan , Bourdet-Sicard Raphaëlle , Castell Margarida , Collado María Carmen , Pérez-Cano Francisco José , Rodríguez-Lagunas María José
Published: June 2024

Immune system development during gestation and suckling is significantly modulated by maternal environmental and dietary factors. Breastfeeding is widely recognized as the optimal source of nutrition for infant growth and immune maturation, and its composition can be modulated by the maternal diet. In the present work, we investigated whether oral supplementation with Bifidobacterium breve M-16V and short-chain galacto-oligosaccharide (scGOS) and long-chain fructo-oligosaccharide (lcFOS) to rat dams during gestation and lactation has an impact on the immune system and microbiota composition of the offspring at day 21 of life. On that day, blood, adipose tissue, small intestine (SI), mesenteric lymph nodes (MLN), salivary gland (SG), cecum, and spleen were collected. Synbiotic supplementation did not affect the overall body or organ growth of the pups. The gene expression of Tlr9, Muc2, IgA, and Blimp1 were upregulated in the SI, and the increase in IgA gene expression was further confirmed at the protein level in the gut wash. Synbiotic supplementation also positively impacted the microbiota composition in both the small and large intestines, resulting in higher proportions of Bifidobacterium genus, among others. In addition, there was an increase in butanoic, isobutanoic, and acetic acid concentrations in the cecum but a reduction in the small intestine. At the systemic level, synbiotic supplementation resulted in higher levels of immunoglobulin IgG2c in plasma, SG, and MLN, but it did not modify the main lymphocyte subsets in the spleen and MLN. Overall, synbiotic maternal supplementation is able to positively influence the immune system development and microbiota of the suckling offspring, particularly at the gastrointestinal level.
Longitudinal Correlations between Molecular Compositions of Stratum Corneum and Breast Milk Factors during Infancy: A Prospective Birth Cohort Study
Authors: Fukuda Risa , Pak Kyongsun , Kiuchi Megumi , Hirata Naoko , Mochimaru Naoko , Tanaka Ryo , Mitsui Mari , Ohya Yukihiro , Yoshida Kazue
Published: June 2024

Breast milk contains numerous factors that are involved in the maturation of the immune system and development of the gut microbiota in infants. These factors include transforming growth factor-β1 and 2, immunoglobin A, and lactoferrin. Breast milk factors may also affect epidermal differentiation and the stratum corneum (SC) barrier in infants, but no studies examining these associations over time during infancy have been reported. In this single-center exploratory study, we measured the molecular components of the SC using confocal Raman spectroscopy at 0, 1, 2, 6, and 12 months of age in 39 infants born at our hospital. Breast milk factor concentrations from their mothers’ breast milk were determined. Correlation coefficients for the two datasets were estimated for each molecular component of the SC and breast milk factor at each age and SC depth. The results showed that breast milk factors and molecular components of the SC during infancy were partly correlated with infant age in months and SC depth, suggesting that breast milk factors influence the maturation of the SC components. These findings may improve understanding of the pathogenesis of skin diseases associated with skin barrier abnormalities.