bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effect of Reactive Sputtering on the Microstructure of Parylene-C
Authors: Raji Akeem , Lee Ye-Seul , Baek Seung-Yo , Yoon Ji-Hyeon , Gasonoo Akpeko , Lee Jonghee , Lee Jae-Hyun
Published: July 2022

Sputtering technique involves the use of plasma that locally heats surfaces of substrates during the deposition of atoms or molecules. This modifies the microstructure by increasing crystallinity and the adhesive properties of the substrate. In this study, the effect of sputtering on the microstructure of parylene-C was investigated in an aluminum nitride (AlN)-rich plasma environment. The sputtering process was carried out for 30, 45, 90 and 120 min on a 5 μm thick parylene-C film. Topography and morphology analyses were conducted on the parylene-C/AlN bilayers. Based on the experimental data, the results showed that the crystallinity of parylene-C/AlN bilayers was increased after 30 min of sputtering and remained saturated for 120 min. A scratch-resistance test conducted on the bilayers depicted that a higher force is required to delaminate the bilayers on top of the substrate. Thus, the adhesion properties of parylene-C/AlN bilayers were improved on glass substrate by about 17% during the variation of sputtering time.
Modified Drive Structure of a Knitting Machine
Authors: Skrivanek Josef , Bilek Martin , Batka Ondrej
Published: July 2022

This paper deals with the problematic of the drive system of small-diameter knitting machines (hereinafter “knitting machines”). An alternative design of a new drive system is presented that addresses the effective working position of selected operating elements, i.e., a cylinder, a dial, and a roller cutter. The design is protected by patent No. 303578, and the authors of this paper also authored the patent. For the description and simulation of the drive system, mathematical models have been elaborated of the existing and new drive system, which include an additional design of a more suitable stroke for the movement of the cylinder. The output of the simulations are the courses of kinematic quantities, torque, and electric current, elucidating the benefits of the new drive system. Based on the structure of the new drive system, a test device has been designed and manufactured to verify functionality and reliability. The new drive system consumes less energy, simplifies the machine frame and reduces noise emissions. The obtained results can help in researching the issue of knitting machine frames, and in addition, the new system brings new technological possibilities for knitting.
A Novel Hybrid Whale Optimization Algorithm for Flexible Job-Shop Scheduling Problem
Authors: Yang Wenqiang , Su Jinzhe , Yao Yunhang , Yang Zhile , Yuan Ying
Published: July 2022

The flexible job shop scheduling problem (FJSP) is an extension of the classical job shop scheduling problem and one of the more well-known NP-hard problems. To get better global optima of the FJSP, a novel hybrid whale optimization algorithm (HWOA) is proposed for solving FJSP, in which minimizing the makespan is considered as the objective. Firstly, the uniformity and extensiveness of the initial population distribution are increased with a good point set (GPS). Secondly, a new nonlinear convergence factor (NCF) is proposed for coordinating the weight of global and local search. Then, a new multi-neighborhood structure (MNS) is proposed, within which a total of three new neighborhoods are used to search for the optimal solution from different directions. Finally, a population diversity reception mechanism (DRM), which ensures to some extent that the population diversity is preserved with iteration, is presented. Seven international benchmark functions are used to test the performance of HWOA, and the results show that HWOA is more efficient. Finally, the HWOA is applied to 73 FJSP and four Ra international instances of different scales and flexibility, and the results further verify the effectiveness and superiority of the HWOA.
Corrigendum of a Theorem on New Upper Bounds for the α-Indices. Comment on Lenes et al. New Bounds for the α-Indices of Graphs. Mathematics 2020, 8, 1668
Authors: Cheng Yen-Jen , Kao Louis , Weng Chih-wen
Published: July 2022

We give a family of counterexamples of a theorem on a new upper bound for the α-indices of graphs in the paper that is mentioned in the title. We also provide a new upper bound for corrigendum.
Boosting Unsupervised Dorsal Hand Vein Segmentation with U-Net Variants
Authors: Lefkovits Szidónia , Emerich Simina , Lefkovits László
Published: July 2022

The identification of vascular network structures is one of the key fields of research in medical imaging. The segmentation of dorsal hand vein patterns form NIR images is not only the basis for reliable biometric identification, but would also provide a significant tool in assisting medical intervention. Precise vein extraction would help medical workers to exactly determine the needle entry point to efficiently gain intravenous access for different clinical purposes, such as intravenous therapy, parenteral nutrition, blood analysis and so on. It would also eliminate repeated attempts at needle pricks and even facilitate an automatic injection procedure in the near future. In this paper, we present a combination of unsupervised and supervised dorsal hand vein segmentation from near-infrared images in the NCUT database. This method is convenient due to the lack of expert annotations of publicly available vein image databases. The novelty of our work is the automatic extraction of the veins in two phases. First, a geometrical approach identifies tubular structures corresponding to veins in the image. This step is considered gross segmentation and provides labels (Label I) for the second CNN-based segmentation phase. We visually observe that different CNNs obtain better segmentation on the test set. This is the reason for building an ensemble segmentor based on majority voting by nine different network architectures (U-Net, U-Net++ and U-Net3+, all trained with BCE, Dice and focal losses). The segmentation result of the ensemble is considered the second label (Label II). In our opinion, the new Label II is a better annotation of the NCUT database than the Label I obtained in the first step. The efficiency of computer vision algorithms based on artificial intelligence algorithms is determined by the quality and quantity of the labeled data used. Furthermore, we prove this statement by training ResNet–UNet in the same manner with the two different label sets. In our experiments, the Dice scores, sensitivity and specificity with ResNet–UNet trained on Label II are superior to the same classifier trained on Label I. The measured Dice scores of ResNet–UNet on the test set increase from 90.65% to 95.11%. It is worth mentioning that this article is one of very few in the domain of dorsal hand vein segmentation; moreover, it presents a general pipeline that may be applied for different medical image segmentation purposes.
Generalized Three-Step Numerical Methods for Solving Equations in Banach Spaces
Authors: Argyros Michael I. , Argyros Ioannis K. , Regmi Samundra , George Santhosh
Published: July 2022

In this article, we propose a new methodology to construct and study generalized three-step numerical methods for solving nonlinear equations in Banach spaces. These methods are very general and include other methods already in the literature as special cases. The convergence analysis of the specialized methods is been given by assuming the existence of high-order derivatives which are not shown in these methods. Therefore, these constraints limit the applicability of the methods to equations involving operators that are sufficiently many times differentiable although the methods may converge. Moreover, the convergence is shown under a different set of conditions. Motivated by the optimization considerations and the above concerns, we present a unified convergence analysis for the generalized numerical methods relying on conditions involving only the operators appearing in the method. This is the novelty of the article. Special cases and examples are presented to conclude this article.
New Z-Eigenvalue Localization Set for Tensor and Its Application in Entanglement of Multipartite Quantum States
Authors: Xiong Liang , Jiang Zhanfeng , Liu Jianzhou , Qin Qi
Published: July 2022

This study focuses on tensor Z-eigenvalue localization and its application in the geometric measure of entanglement for multipartite quantum states. A new Z-eigenvalue localization theorem and the bounds for the Z-spectral radius are derived, which are more precise than some of the existing results. On the other hand, we present theoretical bounds of the geometric measure of entanglement for a weakly symmetric multipartite quantum state with non-negative amplitudes by virtue of different distance measures. Numerical examples show that these conclusions are superior to the existing results in quantum physics in some cases.
An Efficient Methodology for Locating and Sizing PV Generators in Radial Distribution Networks Using a Mixed-Integer Conic Relaxation
Authors: Montoya Oscar Danilo , Ramos-Paja Carlos Andrés , Grisales-Noreña Luis Fernando
Published: July 2022

This paper proposes a new solution methodology based on a mixed-integer conic formulation to locate and size photovoltaic (PV) generation units in AC distribution networks with a radial structure. The objective function comprises the annual expected energy costs of the conventional substation in addition to the investment and operating costs of PV sources. The original optimization model that represents this problem belongs to the family of mixed-integer nonlinear programming (MINLP); however, the complexity of the power balance constraints make it difficult to find the global optimum. In order to improve the quality of the optimization model, a mixed-integer conic (MIC) formulation is proposed in this research in order to represent the studied problem. Numerical results in two test feeders composed of 33 and 69 nodes demonstrate the effectiveness of the proposed MIC model when compared to multiple metaheuristic optimizers such as the Chu and Beasley Genetic Algorithm, the Newton Metaheuristic Algorithm, the Vortex Search Algorithm, the Gradient-Based Metaheuristic Optimization Algorithm, and the Arithmetic Optimization Algorithm, among others. The final results obtained with the MIC model show improvements greater than USD 100,000 per year of operation. All simulations were run in the MATLAB programming environment, using its own scripts for all the metaheuristic algorithms and the disciplined convex tool known as CVX with the Gurobi solver in order to solve the proposed MIC model.
Granular Elastic Network Regression with Stochastic Gradient Descent
Authors: He Linjie , Chen Yumin , Zhong Caiming , Wu Keshou
Published: July 2022

Linear regression is the use of linear functions to model the relationship between a dependent variable and one or more independent variables. Linear regression models have been widely used in various fields such as finance, industry, and medicine. To address the problem that the traditional linear regression model is difficult to handle uncertain data, we propose a granule-based elastic network regression model. First we construct granules and granular vectors by granulation methods. Then, we define multiple granular operation rules so that the model can effectively handle uncertain data. Further, the granular norm and the granular vector norm are defined to design the granular loss function and construct the granular elastic network regression model. After that, we conduct the derivative of the granular loss function and design the granular elastic network gradient descent optimization algorithm. Finally, we performed experiments on the UCI datasets to verify the validity of the granular elasticity network. We found that the granular elasticity network has the advantage of good fit compared with the traditional linear regression model.
Micropolar Dusty Fluid: Coriolis Force Effects on Dynamics of MHD Rotating Fluid When Lorentz Force Is Significant
Authors: Lou Quanfu , Ali Bagh , Rehman Saif Ur , Habib Danial , Abdal Sohaib , Shah Nehad Ali , Chung Jae Dong
Published: July 2022

The main objective of this investigation to examine the momentum and thermal transportation of rotating dusty micropolar fluid flux with suspension of conducting dust particles across the stretched sheet. The novelty of the flow model is the exploration of the significance of boosting the volume concentration of dust particles in fluid dynamics. The governing PDEs of the problem for both phase models are transmuted into nonlinear coupled non-dimensional ODEs by utilizing suitable similarity modifications. The bvp4c technique was utilized in MATLAB script to acquire a graphical representation of the experimental results. This study illustrates the analysis of repercussions of pertinent parameters on non-Newtonian fluid and the dusty phase of fluid. By improving the volume concentration of dust particles and rotating parameters, the axial velocity for both phases depreciates, whereas temperature and transverse velocity for both phases have the opposite behavior. The micro-rotation distribution rises with higher contributions of rotating and material parameters, whereas it decreases against larger inputs of volume concentration of dust particles. The growing strength of the dust volume fraction (ϕd) caused the coefficient of skin friction to decrease along the x direction, and the skin friction coefficient is raised along the y direction.
Internet Addiction, Phubbing, Psychological Variables and Self-Perception of Mathematical Competence in College Students
Authors: Fernández-Andújar Marina , Alonso Marta Oporto , Sorribes Elena , Villalba Vicente , Calderon Caterina
Published: July 2022

Internet Addiction (IA) and phubbing are prevalent, disruptive behaviours among university students. The aim of this study was to explore the relationship between IA and Phubbing with psychological variables (impulsiveness, self-esteem, and psychological distress), academic performance and self-perception of mathematical competence (SMC), as well as possible gender differences. Results showed (n = 715; Mean Age = 21.7) gender differences in lack of planning, emotional investment and somatisation and IA correlated positively with app addiction, mobile addiction, and psychopathology. A total of 26.3% of IA can be explained by a lack of self-control, time and performance management, mobile phone addiction, anxiety and psychological distress. Finally, 71% of students believe that the use of new technologies has worsened their SMC and this is correlated with impaired communication, obsession with mobile phones, IA (Total Phubbing Scale) and impulsiveness. Our results indicate the importance of taking into account psychological variables that affect the development of IA, phubbing, and SMC in the university population.
New Localized Structure for (2+1) Dimensional Boussinesq-Kadomtsev-Petviashvili Equation
Authors: Mu Gui , Zhu Yan , Feng Tingfu
Published: July 2022

In this work, we use a variable separation approach to construct some novel exact solutions of a (2+1)-dimensional Boussinesq-Kadomtsev-Petviashvili equation. Thanks to two variable-separated arbitrary functions, some new soliton excitations and localized structures are obtained. It is observed that large amplitude waves are generated in the process of interaction between two solitons.
Hygrothermal Buckling of Smart Graphene/Piezoelectric Nanocomposite Circular Plates on an Elastic Substrate via DQM
Authors: Alazwari Mashhour A. , Zenkour Ashraf M. , Sobhy Mohammed
Published: July 2022

This paper aims to study the hygrothermal buckling of smart graphene/piezoelectric circular nanoplates lying on an elastic medium and subjected to an external electric field. The circular nanoplates are made of piezoelectric polymer reinforced with graphene platelets that are uniformly distributed through the thickness of the nanoplate. The material properties of the nanocomposite plate are determined based on the modified Halpin-Tsai model. To capture the nanoscale effects, the nonlocal strain gradient theory is applied. Moreover, the principle of virtual work is employed to establish the nonlinear stability equations in the framework of classical theory. The differential quadrature method is utilized to solve the governing equations. Among the important aims of the paper is to study the influences of various parameters such as graphene weight fraction, elastic foundation parameters, external applied electric field, humid conditions, and boundary conditions on the thermal buckling of the smart nanocomposite circular nanoplates. It is found that the increase in graphene components and elastic foundation stiffness enhances the strength of the plates; therefore, the buckling temperature will increase.
Patients with Pulmonary Metastases from Head and Neck Cancer Benefit from Pulmonary Metastasectomy, A Systematic Review
Authors: Schlachtenberger Georg , Doerr Fabian , Menghesha Hruy , Lauinger Patrick , Wolber Philipp , Sabashnikov Anton , Popov Aron-Frederik , Macherey-Meyer Sascha , Bennink Gerardus , Klussmann Jens P. , Wahlers Thorsten , Hekmat Khosro , Heldwein Mathias B.
Published: July 2022

Background and Objectives: The incidence of distant metastases in patients with head and neck cancer (HNC) is approximately 10%. Pulmonary metastases are the most frequent distant location, with an incidence of 70–85%. The standard treatment options are chemo-, immuno- and radiotherapy. Despite a benefit for long-term survival for patients with isolated pulmonary metastases, pulmonary metastasectomy (PM) is not the treatment of choice. Furthermore, many otorhinolaryngologists are not sufficiently familiar with the concept of PM. This work reviews the recent studies of pulmonary metastatic HNC and the results after pulmonary metastasectomy. Materials and Methods: PubMed, Medline, Embase, and the Cochrane library were checked for the case series’ of patients undergoing metastasectomy with pulmonary metastases published since 1 January 2000. Results: We included the data of 15 studies of patients undergoing PM. The 5-year survival rates varied from 21% to 59%, with median survival from 10 to 77 months after PM. We could not identify one specific prognostic factor for long-term survival after surgery. However, at least most studies stated that PM should be planned if a complete (R0) resection is possible. Conclusions: PM showed reliable results and is supposedly the treatment of choice for patients with isolated pulmonary metastases. Patients not suitable for surgery may benefit from other non-surgical therapy. Every HNC patient with pulmonary metastases should be discussed in the multidisciplinary tumor board to optimize the therapy and the outcome.
Urinary Bladder Schistosomiasis Mimicking Neoplasm: A Case Report
Authors: Darraj Majid
Published: July 2022

Schistosomiasis is a neglected disease that is prevalent in tropical and subtropical areas. A 20-year-old woman presented to the emergency room with a history of right flank pain and lower abdominal discomfort for one day, which coincided with the onset of menses. The patient did not provide any history of premenstrual hematuria. The physical examination revealed right costovertebral angle tenderness and was otherwise unremarkable. The urinalysis demonstrated a mild increase in red and white blood cells and no ova or parasite. The blood test was normal, except for eosinophilia. A right pedunculated intraluminal urinary bladder mass was detected by the computerized axial tomographic scan and ultrasonography, and after the transurethral resection of the mass, the patient was diagnosed with urinary schistosomiasis. The patient received two doses of oral praziquantel of 1200 mg every 12 h for one day. The cure was confirmed with a one-month post-treatment follow-up that revealed a normal urine microscope and eosinophil count. The S. haematobium infection should be evaluated as a possible cause of urinary bladder lesion in those who have travelled or lived in endemic areas.
Pre-Hospital Delay in Acute Ischemic Stroke Care: Current Findings and Future Perspectives in a Tertiary Stroke Center from Romania—A Cross-Sectional Study
Authors: Terecoasă Elena Oana , Radu Răzvan Alexandru , Negrilă Anca , Enache Iulian , Cășaru Bogdan , Tiu Cristina
Published: July 2022

Background and objectives: The time interval between stroke onset and hospital arrival is a major barrier for reperfusion therapies in acute ischemic stroke and usually accounts for most of the onset-to-treatment delay. The present study aimed to analyze the pre-hospital delays for patients with acute ischemic stroke admitted to a tertiary stroke center in Romania and to identify the factors associated with a late hospital arrival. Material and methods: The study population consisted of 770 patients hospitalized with the diagnosis of acute ischemic stroke in the University Emergency Hospital Bucharest during a 6-month period, between 1 January and 30 June 2018. Data regarding pre-hospital delays were prospectively collected and analyzed together with the demographic and clinical characteristics of the patients. Results: In total, 31.6% of patients arrived at the hospital within 4.5 h from stroke onset and 4.4% in time intervals between 4.5 and 6 h from the onset, and 28.7% of the patients reached the hospital more than 24 h after onset of symptoms. Transport to hospital by own means was the only factor positively associated with arrival to hospital > 4.5 h from stroke onset and more than doubled the odds of late arrival. Factors negatively associated with hospital arrival > 4.5 h after stroke onset were prior diagnosis of atrial fibrillation, initial National Institute of Health Stroke Scale (NIHSS) score ≥ 16 points, presence of hemianopsia, facial palsy and sensory disturbance. Factors increasing the odds of hospital arrival after 24 h from stroke onset were living alone and living in rural areas. Conclusions: Almost one in three ischemic stroke patients presenting to our center reaches hospital more than 24 h after onset of symptoms. These findings highlight the need for urgent measures to improve not only stroke awareness but also pre-hospital protocols in order to provide timely and appropriate care for our stroke patients.
The Risk of Obstetrical Hemorrhage in Placenta Praevia Associated with Coronavirus Infection Antepartum or Intrapartum
Authors: Pacu Irina , Zygouropoulos Nikolaos , Cristea Alina Elena , Zaharia Cristina , Rosu George-Alexandru , Matei Alexandra , Bodei Liana-Tina , Neacsu Adrian , Ionescu Cringu Antoniu
Published: July 2022

Background and Objectives: The aim was to evaluate the severity of obstetrical bleeding in the third trimester associated with COVID infection in placenta previa and accreta. Materials and Methods: A retrospective study was conducted to compare the risk of obstetrical bleeding in the case of placenta previa with or without associated SARS-CoV-2 infection. Patients presenting with placenta previa before labor were classified into three groups: group A (control) as no infection throughout their pregnancy, group B as confirmed infection during the 1st trimester, and group C as confirmed infection at the time of delivery. Infected patients were stratified according to the severity of signs and symptoms. The severity of obstetrical hemorrhage at birth was assessed quantitatively and qualitatively. All placentas were analyzed histologically to identify similarities. Results: Prematurity and pregnancy-induced hypertension appear significantly related to SARS-CoV-2 infection during the 3rd trimester. Placenta accreta risk increases significantly with infection during the 1st trimester. No statistically significant differences in the severity of hemorrhage associated with childbirth in cases with placenta previa between groups A and C but increased obstetrical bleeding mainly due to emergency hemostatic hysterectomy in group B driven by placenta accrete were detected. Obstetrical hemorrhage at birth in the case of coexistence of the infection was found not to correlate with the severity of the viral disease. Meanwhile, the number of days of hospitalization after birth is related to the specific treatment of COVID infection and not related to complications related to birth. Conclusions: The study finds an increased incidence of placenta accreta associated with placenta previa in cases where the viral infection occurred in the first trimester of pregnancy, associated with an increased incidence of hemostasis hysterectomies in these patients. Placental histological changes related to viral infection are multiple and more important in patients who had COVID infection in the first trimester.
A Tension-Band Wiring Technique for Direct Fixation of a Chaput Tubercle Fracture: Technical Note
Authors: Yeo Eui-Dong , Jung Ki-Jin , Hong Yong-Cheol , Hong Chang-Hwa , Lee Hong-Seop , Won Sung-Hun , Yoon Sung-Joon , Kim Sung-Hwan , Ji Jae-Young , Lee Dhong-Won , Kim Woo-Jong
Published: July 2022

Few reports have described direct fixation of the Chaput tubercle; screw fixation is usually employed. Herein, we introduce a novel technique for Chaput tubercle fixation using tension-band wiring. This technique is applicable to fractured tubercles of various sizes and has the advantage that the fragment breakage that may occur during screw fixation is impossible. In addition, our technique increases fixation strength.
Advances in Bio-Based Materials for Food Packaging Applications
Authors: Gouanvé Fabrice
Published: July 2022

Food packaging is defined as a group of boxes, envelopes, papers, and coatings that are employed in order to increase the shelf life of foodstuffs [...]
A Sharp-Interface Model of the Diffusive Phase Transformation in a Nickel-Based Superalloy
Authors: Munk Lukas , Reschka Silvia , Maier Hans Jürgen , Wriggers Peter , Löhnert Stefan
Published: July 2022

A sharp-interface model employing the extended finite element method is presented. It is designed to capture the prominent γ-γ′ phase transformation in nickel-based superalloys. The novel combination of crystal plasticity and sharp-interface theory outlines a good modeling alternative to approaches based on the Cahn–Hilliard equation. The transformation is driven by diffusion of solute γ′-forming elements in the γ-phase. Boundary conditions for the diffusion problem are computed by the stress-modified Gibbs–Thomson equation. The normal mass balance of solute atoms at the interface yields the normal interface velocity, which is integrated in time by a level set procedure. In order to capture the influence of dislocation glide and climb on interface motion, a crystal plasticity model is assumed to describe the constitutive behaviour of the γ-phase. Cuboidal equilibrium shapes and Ostwald ripening can be reproduced. According to the model, in low γ′ volume-fraction alloys with separated γ′-precipitates, interface movement does not have a significant effect on tensile creep behaviour at various lattice orientations.
Fabrication and Characterization of Porous Copper with Ultrahigh Porosity
Authors: Xiao Jian , Li Yong , Liu Jinming , Zhao Qianlei
Published: July 2022

The fabrication of porous copper with ultrahigh porosity by adding 90% spacer content was an unsolved technical problem in the field. In this study, the green compacts placed on a layer wire mesh during the decomposition process of needlelike carbamide as space holder with volume content up to 90% was successfully conducted to fabricate nondestructive porous copper. Compared with the green compacts directly placed on an alumina plate, the use of this support was crucial for manufacturing highly-porous copper. Characterization of macro- and microscopic morphologies as well as quasi-static compressive test for the obtained porous copper samples was carried out. The results show that the porosity of porous copper samples with 87.3% was slightly smaller than the spacer content. The SEM observation indicates that the internal pores of porous copper formed an open-cell structure and its skeleton was very dense. The compressive tests show that the stress–strain curve of a porous copper sample exhibits the typical characteristics of elastic-plastic metal foam. The energy absorption properties of porous copper samples were also comparable. This study provides a possibility for the preparation of porous copper and other metals with ultrahigh porosity by the well-known space holder method.
Transparent Silver Coatings with Copper Addition for Improved Conductivity by Combined DCMS and HiPIMS Process
Authors: Vitelaru Catalin , Parau Anca C. , Dinu Mihaela , Pana Iulian , Constantin Lidia R. , Sobetkii Arcadie , Iordache Iulian
Published: July 2022

The demand for transparent conductive coatings has increased over recent years, leading to the development of various technical solutions. One of the approaches is to use metallic coatings very close to their coalescence thickness, so that a good compromise between transparency and conductivity is obtained. In this contribution, a combination of two elements with high potential in this field is used, namely silver and copper. The continuity of silver films on a dielectric transparent substrate is significantly improved by the addition of a copper seed layer that promotes the formation of a continuous layer at smaller effective thicknesses. Two distinct deposition processes are used for the deposition of the two materials, namely HiPIMS (High Power Impulse magnetron sputtering) for copper and DC sputtering for silver. The use of HiPIMS enables a better control of the structure and quantity of deposited material, allowing us to deposit a very small amount of material. The mono-element coatings are characterized from the optical and electrical point of view, and then mixed to form a structure with better transparency, up to 80% in the visible spectrum, good electrical properties, resistivity of ~2 × 10−5 (Ω × cm), and significantly lower surface roughness, down to 0.2 nm.
Hydrogen as a Temporary Alloying Element for Establishing Specific Microstructural Gradients in Ti-6Al-4V
Authors: Schmidt Christopher David , Christ Hans-Jürgen , Von Hehl Axel
Published: July 2022

Parts of vehicles, such as landing gear components of aircrafts, are subject to growing demands in terms of sustainability via lightweight design and durability. To fulfill these requirements, the development of thermochemical processes is auspicious. Titanium alloys allow a heat treatment in hydrogen-containing atmosphere for temporary hydrogen alloying, often called thermohydrogen treatment (THT). The investigation presented intends to realize a local microstructure modification of Ti-6Al-4V by means of THT. The study aims to use hydrogen (H) as a promoter for changing the local distribution and morphology of strengthening precipitates during THT as well as the local grain size (microstructural gradient). Both shall improve the fatigue properties of the material after hydrogen degassing. To derive suitable thermohydrogen treatment process parameters, the resulting fatigue crack propagation resistance and fracture toughness after different solution heat treatments are determined experimentally and compared to each other. Moreover, various graded microstructures are evaluated after hydrogen uptake (hydrogenation) and hydrogen degassing (dehydrogenation) using numerically simulated hydrogen concentration profiles, observed hardness curves, metallographically determined microstructure gradients and the corresponding results of the phase analysis by means of X-ray diffraction. The study shows that hydrogenation at 500 °C and dehydrogenation at 750 °C enables the generation of a promising microstructural gradient.
Development of Fermented Shrimp Shell Product with Hypoglycemic and Hypolipidemic Effects on Diabetic Rats
Authors: Huang Chung-Hsiung , Lin Chih-Heng , Huang Hsiao-Han , Tsai Guo-Jane
Published: July 2022

In 2020, approximately 9.3 billion tons of crustaceans were consumed, and 45–48% of shrimp shell (SS) by-products were discarded as waste. In this study, the SS of Litopenaeus vannamei was fermented by Lactobacillus plantarum LV33204, Stenotrophomonas maltophilia LV2122 (strong proteolytic activity), and Aeromonas dhakensis LV1111 (chitin-degrading activity), and the optimal fermentation conditions of liquid-fermented SS was established. Contents of total peptide, astaxanthin, and total phenolic content of the fermented SS were significantly higher than that of unfermented SS. In the presence of fermented SS, glucose uptake and insulin resistance of TNF-α-stimulated FL83B hepatocytes were markedly improved. Furthermore, daily oral supplement of fermented SS to streptozotocin (STZ)/nicotinamide (NA)-induced diabetic rats for 7 weeks significantly reduced plasma glucose and insulin resistance. Meanwhile, ingestion of fermented SS might enhance hepatic catabolism of glucose by increasing hexokinase and glucose-6-phosphate dehydrogenase activity and decreasing glucose-6-phosphatase activity. In addition, the fermented SS downregulated plasma total cholesterol (TG), triglycerides (TCs), low-density lipoprotein cholesterol (LDL-C), liver TG, and TC and lipid peroxidation levels in diabetic rats. In conclusion, a biorefinery process for waste SS was established through mixed strain fermentation. The in vitro and in vivo data reveal that the fermented SS is a promising functional food for the management of diabetic hyperglycemia and hyperlipidemia.
Accelerometer-Based Sedentary Time, Physical Activity, and Serum Metabolome in Young Men
Authors: Vaara Jani P. , Kyröläinen Heikki , Vasankari Tommi , Kainulainen Heikki , Raitanen Jani , Kujala Urho M
Published: July 2022

Physical activity (PA) has been shown to associate with many health benefits but studies with metabolome-wide associations with PA are still lacking. Metabolome studies may deepen the mechanistic understanding of PA on the metabolic pathways related to health outcomes. The aim of the present study was to study the association of accelerometer based sedentary time (SB) and PA with metabolome measures. SB and PA were measured by a hip-worn accelerometer in 314 young adult men (age: mean 28, standard deviation 7 years). Metabolome was analyzed from fasting serum samples consisting of 66 metabolome measures (nuclear magnetic resonance-based metabolomics). The associations were analyzed using a single and compositional approach with regression analysis. The compositional analysis revealed that 4 metabolome variables were significantly (γ: 0.32–0.44, p ≤ 0.002), and 13 variables with a trend towards significance (p < 0.05), associated with SB with varying metabolic pathways. Trends towards significant associations (p < 0.05) were observed with 5 variables with moderate-to-vigorous and 1 variable with light intensity PA with varying metabolic pathways. The present study revealed possible mechanistic pathways relevant for the interaction between especially SB but also PA of moderate-to-vigorous intensity with ketone bodies and amino acid concentration related to exercised-induced energy production and lipid metabolism.
Gold Nanocone Array with Extensive Electromagnetic Fields for Highly Reproducible Surface-Enhanced Raman Scattering Measurements
Authors: Fujiwara Satoko , Kawasaki Daiki , Sueyoshi Kenji , Hisamoto Hideaki , Endo Tatsuro
Published: July 2022

Surface-enhanced Raman scattering (SERS) is a technique used to distinguish the constitution of disease-related biomarkers in liquid biopsies, such as exosomes and circulating tumor cells, without any recognition elements. Previous studies using metal nanoparticle aggregates and angular nanostructures have achieved the detection of various biomarkers owing to strong hot spots and electromagnetic (EM) fields by localized surface plasmon resonance (LSPR). Although these SERS platforms enable significant enhancement of Raman signals, they still have some problems with the fabrication reproducibility of platforms in obtaining reproducible SERS signals. Therefore, highly reproducible fabrication of SERS platforms is required. Here, we propose the application of a polymer-based gold (Au) nanocone array (Au NCA), which extensively generates an enhanced EM field near the Au NCA surface by LSPR. This approach was experimentally demonstrated using a 785 nm laser, typically used for SERS measurements, and showed excellent substrate-to-substrate reproducibility (relative standard deviation (RSD) < 6%) using an extremely simple fabrication procedure and very low laser energy. These results proved that a Au NCA can be used as a highly reproducible SERS measurement to distinguish the constitution of biomarkers.
Nanoscale Detonation Carbon Demonstrates Biosafety in Human Cell Culture
Authors: Malakhova Anastasia A. , Rybin Denis K. , Shtertser Alexandr A. , Dudina Dina V.
Published: July 2022

The production method of nanoscale detonation carbon (NDC) has recently been developed at Lavrentyev Institute of Hydrodynamics SB RAS. This method uses the reaction of acetylene with oxygen conducted in the detonation mode in fuel-rich acetylene–oxygen mixtures. The morphology and structural features of the NDC particles can be varied by changing the concentration of oxygen in the gaseous mixtures. The particles of NDC can serve as reinforcements in metal matrix composites and additives imparting electrical conductivity to polymer matrix composites. Before NDC can be considered for industrial applications, it is necessary to address the related biological safety concerns. The present work was aimed at determining the cytotoxicity of NDC. The NDC powders with two morphologies (obtained using different acetylene/oxygen ratios) were tested on HEK293A human cells. The NDC powder was added to the culture medium in concentrations ranging from 10 ng/mL to 400 μg/mL. The cell viability was determined by a colorimetric EZ4U test and a real-time cell analyzer xCELLigence. None of the NDC samples showed a cytotoxic effect. The results of this study allow us to recommend NDC as a safe and useful product for the development of advanced carbon-based and composite materials.
A Miniature Soft Sensor with Origami-Inspired Self-Folding Parallel Mechanism
Authors: Shi Yongqi , Wang Gang , Sun Wenguang , Ya Yunfeng , Liu Shuhan , Fang Jiongjie , Yuan Feiyang , Duo Youning , Wen Li
Published: July 2022

Miniature soft sensors are crucial for the perception of soft robots. Although centimeter-scale sensors have been well developed, very few works addressed millimeter-scale, three-dimensional-shaped soft sensors capable of measuring multi-axis forces. In this work, we developed a millimeter-scale (overall size of 6 mm × 11 mm × 11 mm) soft sensor based on liquid metal printing technology and self-folding origami parallel mechanism. The origami design of the sensor enables the soft sensor to be manufactured within the plane and then fold into a three-dimensional shape. Furthermore, the parallel mechanism allows the sensor to rotate along two orthogonal axes. We showed that the soft sensor can be self-folded (took 17 s) using a shape-memory polymer and magnets. The results also showed that the sensor prototype can reach a deformation of up to 20 mm at the tip. The sensor can realize a measurement of external loads in six directions. We also showed that the soft sensor enables underwater sensing with a minimum sensitivity of 20 mm/s water flow. This work may provide a new manufacturing method and insight into future millimeter-scale soft sensors for bio-inspired robots.
First Cases of Candida auris in a Referral Intensive Care Unit in Piedmont Region, Italy
Authors: Corcione Silvia , Montrucchio Giorgia , Shbaklo Nour , De Benedetto Ilaria , Sales Gabriele , Cedrone Martina , Vita Davide , Costa Cristina , Zozzoli Susanna , Zaccaria Teresa , Silvestre Carlo , Cavallo Rossana , Brazzi Luca , De Rosa Francesco Giuseppe
Published: July 2022

Candida auris is an emerging healthcare-associated infection that can easily cause dissemination in hospitals through colonizing the skin and contaminating environmental surfaces, especially in Intensive Care Units (ICU). Difficulties with identification of this organism, uncertainty about routes of transmission and antifungals resistance have impacted significantly outbreak detection and management. Here, we describe our experience with colonization/infection of C. auris among critically ill patients, admitted to a referral ICU of a University Hospital, in a transitional period (July 2021–March 2022) between management of non-COVID-19 and COVID-19 patients due to the reconversion of the ICU between two waves. A total of 8 patients presented colonization from C. auris, and two of them developed invasive infection from C. auris. The fungal pathogen was cultured from different sites: the skin (7 isolates), urine (2), respiratory tract (1), blood (1). The median time from admission to first detection is 24 days with 100% of patients requiring mechanical ventilation. All 8 patients received broad-spectrum antibiotic therapy for bacterial infections before identification of C. auris; 62.5% of the patients had prior antifungal exposure; 87.5% received steroids; 37.5% patients used immunomodulatory; and 75% had severe COVID-19 illness prior to C. auris identification. Only two cases (25%) were treated with antifungals as C. auris infections (1 patient for suspected UTI; 1 patient with candidemia). Infection control measures, including rapid microbiological identification, contact isolation, screening of contacts, antisepsis of colonized patients, dedicated equipment, cleaning and disinfection of the environment and subsequent follow-up sampling, remain essential in critically ill patients. Our experience highlights the importance of establishing a multidisciplinary model and bundling of practices for preventing C. auris’ spread.
Listeria monocytogenes Pathogenesis: The Role of Stress Adaptation
Authors: Sibanda Thulani , Buys Elna M.
Published: July 2022

Adaptive stress tolerance responses are the driving force behind the survival ability of Listeria monocytogenes in different environmental niches, within foods, and ultimately, the ability to cause human infections. Although the bacterial stress adaptive responses are primarily a necessity for survival in foods and the environment, some aspects of the stress responses are linked to bacterial pathogenesis. Food stress-induced adaptive tolerance responses to acid and osmotic stresses can protect the pathogen against similar stresses in the gastrointestinal tract (GIT) and, thus, directly aid its virulence potential. Moreover, once in the GIT, the reprogramming of gene expression from the stress survival-related genes to virulence-related genes allows L. monocytogenes to switch from an avirulent to a virulent state. This transition is controlled by two overlapping and interlinked transcriptional networks for general stress response (regulated by Sigma factor B, (SigB)) and virulence (regulated by the positive regulatory factor A (PrfA)). This review explores the current knowledge on the molecular basis of the connection between stress tolerance responses and the pathogenesis of L. monocytogenes. The review gives a detailed background on the currently known mechanisms of pathogenesis and stress adaptation. Furthermore, the paper looks at the current literature and theories on the overlaps and connections between the regulatory networks for SigB and PrfA.
Effect of Solar Radiation on Skin Microbiome: Study of Two Populations
Authors: Harel Nurit , Reshef Leah , Biran Dvora , Brenner Sarah , Ron Eliora Z. , Gophna Uri
Published: July 2022

Here, we examined the skin microbiome of two groups of healthy volunteers living on the Mediterranean coast with different exposures to sun radiation. One group, exposed to the sun in the summer, was compared with a group covered with clothing throughout the year. The seasonal effects on the skin microbiome of three body sites were determined before and after summer. Surprisingly, at the phyla level, there were no significant differences in microbiome diversity between the groups. Furthermore, within each group, there were no significant seasonal differences in high-abundance species at any of the sampling sites. These results suggest that the skin microbiome, developed over years, remains stable even after several months of exposure to summer weather, direct sunlight and humidity. However, in the group exposed to the sun during the summer months, there were significant differences in low-abundance species in sun-exposed areas of the skin (the inner and outer arm). These subtle changes in low-abundance species are interesting, and their effect on skin physiology should be studied further.
Paleoenvironmental and Bio-Sequence Stratigraphic Analysis of the Cretaceous Pelagic Carbonates of Eastern Tethys, Sulaiman Range, Pakistan
Authors: Ullah Shuja , Jan Irfan U. , Hanif Muhammad , Latif Khalid , Mohibullah Mohibullah , Sabba Mahnoor , Anees Aqsa , Ashraf Umar , Vo Thanh Hung
Published: July 2022

The Cretaceous pelagic carbonate succession, i.e., Goru Formation was studied in the Chutair Section, Sulaiman Range, representing part of the eastern Tethys for the paleoenvironment and bio-sequence stratigraphy. Eight planktonic foraminiferal biozones are identified which include: 1. Muricohedbergella planispira Interval Zone; 2. Ticinella primula Interval Zone; 3. Biticinella breggiensis Interval Zone; 4. Rotalipora appenninica Interval Zone; 5. Rotalipora cushmani Total Range Zone; 6. Whiteinella archeocretacea Partial Range Zone; 7. Helvetoglobotruncana helvetica Total Range Zone; and 8. Marginotruncana sigali Partial Range Zone representing Albian-Turonian age. The petrographic studies revealed five microfacies: 1. Radiolarians-rich wacke-packestone microfacies; 2. Radiolarians-rich wackestone microfacies; 3. Planktonic foraminiferal wacke-packestone microfacies; 4. Planktonic foraminiferal wackestone microfacies; and 5. Planktonic foraminiferal packestone microfacies; indicating deposition of the Goru Formation in outer-ramp to deep basinal settings. Based on the facies variations and planktonic foraminiferal biozones, the 2nd and 3rd order cycles are identified, which further include six transgressive and five regressive system tracts. The sea level curve of the Goru Formation showed fluctuation between outer-ramp and deep-basin, showing the overall transgression in the 2nd order cycle in the study area, which coincides with Global Sea Level Curve; however, the 3rd order cycle represents the local tectonic control during deposition of the strata.
Recovery of Rare Earth Elements from Mining Tailings: A Case Study for Generating Wealth from Waste
Authors: Echeverry-Vargas Luver , Ocampo-Carmona Luz Marina
Published: July 2022

The growing demand for rare earth elements (REE) driven by their applications in modern technologies has caused the need to search for alternative sources of these elements as their extraction from traditional deposits is limited. A potential source of light rare earth elements (LREE) may be the monazite present in the mining waste generated in the Bagre-Nechí mining district in Colombia due to the processing of sands containing alluvial gold. Consequently, in this research, a systematic evaluation has been carried out for the extraction of Ce, La, and Nd from a leach liquor obtained from monazite present in alluvial gold mining tailings. The leaching process carried out with HCl indicated the recovery of approximately 90% of La and Nd and ∼60% of Ce; the solvent extraction tests of these elements showed that increasing the contact time and pH of the leaching liquor positively affects the extraction of lanthanum, cerium, and neodymium, achieving extractions close to 100% with D2EHPA and to a lesser extent with Cyanex572. McCabe–Thiele diagrams for extraction with D2EHPA indicated the requirement of three stages for the extraction of Ce, La and Nd.