bluuebunny/crossref_metadata_2025 huggingface dataset:
Selection of Inertial and Power Curtailment Control Methods for Wind Power Plants to Enhance Frequency Stability
Authors: Lim SungHoon , Baek Seung-Mook , Park Jung-Wook
Published: April 2022

As renewable energy penetrates the power system, system operators are required to curtail output power from generation units to balance the power supply and demand. However, large curtailment from wind power plants (WPPs) may instantly cause excessive output power decrement, causing system frequency to drop significantly before reaching its nominal value. In order to solve this problem, this paper proposes a cooperative control framework to determine the operation of WPPs in two control methods, which are the stepwise inertial control (SIC) method and the curtailed control method. The proposed framework first determines the WPPs to operate in the curtailed control method to provide the required power curtailment. Next, it determines the WPPs to operate in the SIC method considering their releasable kinetic energy to provide an effective inertial response and compensate for the sudden excessive output power decrement caused by other WPPs operated in the curtailed control method. Therefore, each WPP is operated in one of two control methods to provide required power curtailment while reducing the sudden excessive output power decrement. To verify the effectiveness of the proposed cooperative control framework, several case studies are carried out on the practical South Korea electric power system.
Research on Oil Mist Leakage of Bearing in Hydropower Station: A Review
Authors: Sun Jie , Zhang Yuquan , Liu Bin , Ge Xinfeng , Zheng Yuan , Fernandez-Rodriguez Emmanuel
Published: April 2022

Hydropower is a clean and renewable energy, fundamental to the attainment of a sustainable society. Despite its efficacy and success, there is a need to address the hydroelectric stations’ oil throwing and mist leakage, resulting in the deterioration of the generating units, water, and biodiversity. The conventional engineering measures to deal with oil mist leakage include: the reduction in the operating pad and oil temperature, optimization of the oil circulation loop in the oil tank, improvement of the sealing performance, and design of the oil mist emission device. However, the problem of oil mist leakage of bearings is complex, intractable, and cannot be solved by only one method. Numerical simulation can help to solve the oil mist problem and make up for the shortage of engineering measures. Yet, the mass transfer, involving multi-component and multi-phase flow, becomes a limitation for many numerical studies. As a result, this paper seeks to integrate the solutions by reviewing two influences: the global measures of oil mist leakage proof in the oil tank of bearings in the past 40 years, and the views and experiences of engineering practices. These findings offer some relevant insights into the effectiveness of the applied methods and solving of the oil mist leakage problem.
Improving Characteristics of LUT-Based Sequential Blocks for Cyber-Physical Systems
Authors: Barkalov Alexander , Titarenko Larysa , Krzywicki Kazimierz
Published: April 2022

A method is proposed for optimizing circuits of sequential devices which are used in cyber-physical systems (CPSs) implemented using field programmable gate arrays (FPGAs). The optimizing hardware is a very important problem connected with implementing digital parts of CPSs. In this article, we discuss a case when Mealy finite state machines (FSMs) represent behaviour of sequential devices. The proposed method is aimed at optimization of FSM circuits implemented with look-up table (LUT) elements of FPGA chip. The method aims to reduce the LUT count of Mealy FSMs with extended state codes. The method is based on finding a partition of the set of internal states by classes of compatible states. To reduce LUT count, we propose a special kind of state codes named composite state codes. The composite codes include two parts. The first part includes the binary codes of states as elements of some partition class. The second part consists of the code of corresponding partition class. Using composite state codes allows us to obtain FPGA-based FSM circuits with exactly two levels of logic. If some conditions hold, then any FSM function from the first level is implemented by a single LUT. The second level is represented as a network of multiplexers. Each multiplexer generates either an FSM output or input memory function. An example of synthesis is shown. The experiments prove that the proposed approach allows us to reduce hardware compared with two methods from Vivado, JEDI-based FSMs, and extended state assignment. Depending on the complexity of an FSM, the LUT count is reduced on average from 15.46 to 68.59 percent. The advantages of the proposed approach grow with the growth of FSM complexness. An additional positive effect of the proposed method is a decrease in the latency time.
Association of Plasma Carotenoid and Malondialdehyde Levels with Physical Performance in Korean Adolescents
Authors: Joo Heeyeon , Hwang Jiyoung , Kim Ji Yeon , Park Saejong , Kim Hyesook , Kwon Oran
Published: April 2022

Increased oxidative stress has been shown to lead to muscle damage and reduced physical performance. The antioxidant mechanism is most likely to reduce these relationships, but in the context of the action of carotenoids, more research is needed. This study aimed to investigate whether carotenoids modify the association between plasma malondialdehyde (MDA) and physical performance in Korean adolescents. The study sample consisted of 381 adolescents (164 boys, 217 girls) aged 13–18, who participated in the 2018 National Fitness Award Project. We quantified α-carotene, β-carotene, β-cryptoxanthin, lutein, zeaxanthin, lycopene, and MDA levels in plasma using HPLC with photodiode array detection. Among boys but not girls, plasma MDA level was negatively associated (β = −0.279, p = 0.0030) with total plasma carotenoid levels and marginally negatively associated (β = −0.907, p = 0.0876) with absolute hand grip strength. After adjustment for covariates in boys, the MDA level was negatively associated with absolute hand grip strength and relative hand grip strength; this association was observed only in groups with individual carotenoid and total carotenoid values below the median. These findings support a significant association between plasma MDA level and hand grip strength, and this association has been potentially modified by plasma levels of carotenoids in Korean male adolescents.
In Vivo Complete-Arch Implant Digital Impressions: Comparison of the Precision of Three Optical Impression Systems
Authors: Orejas-Perez Jaime , Gimenez-Gonzalez Beatriz , Ortiz-Collado Ignacio , Thuissard Israel J. , Santamaria-Laorden Andrea
Published: April 2022

(1) Multiple in vitro studies reported insufficient accuracy of intraoral scanners (IOSs) for complete-arch multiple implant impression. The aim of the study is to analyze the precision of three IOSs, PIC dental (Pic dental, Iditec North West SL), TRIOS 3 (3Shape), and True Definition (Midmark Corporation) and the influence of several factors in the edentulous complete maxillary and mandibular arch. (2) A fully edentulous patient with eight implants in the maxillary and in the mandibular jaw was selected. Five impressions were taken per system and arch. A suprastructure was designed on each digital working cast. The precision was analyzed comparing each of the 28 distances and seven relative angulations of the abutments of all the designed suprastructures. The descriptive statistics, the Student’s t-test, and the ANOVA test were used to analyze the data (α = 0.05). (3) Significant differences were observed when comparing the IOSs in some of the distances and angulations. (4) The increase in the distance between implants affected the precision of T and TD but not the PIC system. The type of arch did not affect the PIC precision, but the T and TD systems performed worse in the mandibular arch. The system with the best precision was the PIC, followed by TD, and then T.
Sleep and Sleepiness Measured by Diaries and Actigraphy among Norwegian and Austrian Helicopter Emergency Medical Service (HEMS) Pilots
Authors: Flaa Tine Almenning , Bjorvatn Bjørn , Pallesen Ståle , Zakariassen Erik , Harris Anette , Gatterbauer-Trischler Pia , Waage Siri
Published: April 2022

The study examined sleep and sleepiness among shift working Helicopter Emergency Medical Service pilots from Norway (Norwegian Air Ambulance; NAA) and Austria (Christophorus Flugrettungverein; CFV). Both pilot groups (N = 47) worked seven consecutive 24 h shifts. Sleep was assessed by diaries and actigraphy while sleepiness was assessed by the Karolinska Sleepiness Scale, all administered throughout the workweek. The results indicated that all pilots had later bedtime (p < 0.05) and wake-up time (p < 0.01) as they approached the workweek end, but no change during the workweek was evident regarding wake after sleep onset, time in bed, total sleep time, or sleep efficiency. The NAA pilots had later bedtime (p < 0.001) and wake-up time (p < 0.001), spent more time awake after sleep onset (p < 0.001), more time in bed (p < 0.001), slept longer (p < 0.01), and had lower sleep efficiency (p < 0.001) compared with the CFV pilots. The sleepiness levels of all pilots were slightly elevated on the first workday but lower on the following workdays (day 2p < 0.001, day 3p < 0.05). For both pilot groups, no major change in sleep or sleepiness parameters throughout the workweek was detected. The NAA pilots reported somewhat more disturbed sleep but obtained more sleep compared with the CFV pilots.
Spectrum of BRCA1/2 Mutations in Romanian Breast and Ovarian Cancer Patients
Authors: Vidra Radu , Ciuleanu Tudor Eliade , Nemeș Adina , Pascu Oana , Heroiu Ana Maria , Antone Nicoleta , Vidrean Andreea Iulia , Oprean Cristina Marinela , Pop Laura Ancuta , Berindan-Neagoe Ioana , Eniu Rares , Eniu Alexandru
Published: April 2022

Background: About 10,000 women are diagnosed with breast cancer and about 2000 women are diagnosed with ovarian cancer each year in Romania. There is an insufficient number of genetic studies in the Romanian population to identify patients at high risk of inherited breast and ovarian cancer. Methods: We evaluated 250 women of Romanian ethnicity with BC and 240 women of Romanian ethnicity with ovarian cancer for the presence of damaging germline mutations in breast cancer genes 1 and 2 (BRCA1 and BRCA2, respectively) using Next-Generation Sequencing (NGS) technology. Results: Of the 250 breast cancer patients, 47 carried a disease-predisposing BRCA mutation (30 patients (63.83%) with a BRCA1 mutation and 17 patients (36.17%) with a BRCA2 mutation). Of the 240 ovarian cancer patients, 60 carried a BRCA mutation (43 patients (72%) with a BRCA1 mutation and 17 patients (28%) with a BRCA2 mutation). In the BRCA1 gene, we identified 18 variants (4 in both patient groups (ovarian and breast cancer patients), 1 mutation variant in the BC patient group, and 13 mutation variants in the ovarian cancer patient group). In the BRCA2 gene, we identified 17 variants (1 variant in both ovarian and breast cancer patients, 6 distinct variants in BC patients, and 10 distinct variants in ovarian cancer patients). The prevailing mutation variants identified were c.3607C>T (BRCA1) (18 cases) followed by c.5266dupC (BRCA1) (17 cases) and c.9371A>T (BRCA2) (12 cases). The most prevalent mutation, BRCA1 c.3607C>T, which is less common in the Romanian population, was mainly associated with triple-negative BC and ovarian serous adenocarcinoma. Conclusion: The results of our analysis may help to establish specific variants of BRCA mutations in the Romanian population and identify individuals at high risk of hereditary breast and ovarian cancer syndrome by genetic testing.
Profit-Influencing Factors in Orthopedic Surgery: An Analysis of Costs and Reimbursements
Authors: Rohrer Felix , Farokhnia Aresh , Nötzli Hubert , Haubitz Frederik , Hermann Tanja , Gahl Brigitta , Limacher Andreas , Brügger Jan
Published: April 2022

The aging population and the associated demand for orthopedic surgeries are increasing health costs. Although the Diagnostic Related Groups (DRG) system was introduced to offer incentives for hospitals, concerns remain that reimbursements for older and frail patients do not cover all hospital expenses. We investigated further: (1) Does age influence net financial results in orthopedic surgery? (2) Are there patient or surgical factors that influence results? This retrospective, monocentric study compares costs and reimbursements for orthopedic patients in a tertiary care hospital in Switzerland between 2015 and 2017. The data of 1230 patients were analyzed. Overall, the net results for the hospital were positive, despite 19.5% of patients being treated at a loss. We did not find any correlation between age and profitability (p = 0.61). Patient-related factors associated with financial losses were female sex (p < 0.001) and diabetes (p = 0.013). Patients free of serious comorbidities (p = 0.012) or with a higher cost weight (p < 0.001) were more often profitable. A longer length of stay was associated with higher losses (p < 0.001). This is the first study to address the Swiss DRG reimbursement system in a broad orthopedic population, while also analyzing specific patient and surgical factors. Overall, the reimbursement system is fair, but could better account for certain interventions.
Environmental Sustainability Assessment of the European Union’s Capital Cities
Authors: Czupich Mariusz , Łapińska Justyna , Bartoš Vojtěch
Published: April 2022

The growing flow of people into cities causes several challenges for their functioning. This brings the need to ensure, for example, efficient transport, sustainable waste, and appropriate energy policy. Particularly capital cities are exposed to the above-mentioned risks, due to their large numbers and densities of inhabitants. Therefore, the state of the environment in cities should be monitored systematically. The research aim of this article is to evaluate the level of environmental sustainability in capitals of European Union countries. A synthetic indicator was made up of diagnostic variables, using quantitative and qualitative indicators relating to the quality of the environment. Based on the ranking, results reveal that Europe is spatially divided according to the level of environmental quality. The best results were achieved by capital cities of the northern European countries. The analysis presented here has some application potential. It can serve to identify challenges to improving the quality of the environment, and to raise public awareness of the importance of changing individual behaviour (e.g., use of public transport).
A Scoping Review: Mapping the Evidence for Undergraduate Concussion Education and Proposing the Content for Medical Student Concussion Teaching
Authors: Gardner Nick , Heron Neil
Published: April 2022

Introduction: Concussion is a common yet complex condition, with each new case requiring assessment by a medical doctor. Recent research has shown that doctors working in the UK have significant knowledge deficits regarding concussion diagnosis and management. Aim: The aim of this scoping review was to map out the evidence about how undergraduate medical students are being educated about concussion. Method: This scoping review involved seven research papers identified by searching five online databases in October 2020. Search terms relevant to concussion included: brain injuries, post-concussion syndrome, brain concussion and concussion, combined with search criteria for undergraduate education: medical students, undergraduate medical education, or curriculum. Results: All seven papers were published in North America, with five papers recruiting medical students from single institutions (n = 590) and two papers surveying universities. Canadian medical schools have shown an upward trend in the quantity of teaching about concussion-specific teaching: from 0.57 to 2.65 h between 2012 and 2018. Lectures were the commonest mode of delivery of teaching, followed by problem-based learning and clinical rotations. The studies reach a common conclusion that medical students are not being adequately prepared for diagnosing and managing concussion, with insufficient undergraduate teaching, particularly exposure during clinical rotations, cited as the cause. Conclusions: Concussion: education of medical students is inadequate in North America. Medical schools should help address this by providing lectures and clinical presentations on concussion to learn from, particularly via problem-based learning. There is a paucity of evidence about concussion education in other geographical areas.
Telecardiology in Rural Practice: Global Trends
Authors: Yamano Takashi , Kotani Kazuhiko , Kitano Naomi , Morimoto Junko , Emori Hiroki , Takahata Masahiro , Fujita Suwako , Wada Teruaki , Ota Shingo , Satogami Keisuke , Kashiwagi Manabu , Shiono Yasutsugu , Kuroi Akio , Tanimoto Takashi , Tanaka Atsushi
Published: April 2022

The management of cardiovascular diseases in rural areas is plagued by the limited access of rural residents to medical facilities and specialists. The development of telecardiology using information and communication technology may overcome such limitation. To shed light on the global trend of telecardiology, we summarized the available literature on rural telecardiology. Using PubMed databases, we conducted a literature review of articles published from January 2010 to December 2020. The contents and focus of each paper were then classified. Our search yielded nineteen original papers from various countries: nine in Asia, seven in Europe, two in North America, and one in Africa. The papers were divided into classified fields as follows: seven in tele-consultation, four in the telemedical system, four in the monitoring system, two in prehospital triage, and two in tele-training. Six of the seven tele-consultation papers reported the consultation from rural doctors to urban specialists. More reports of tele-consultations might be a characteristic of telecardiology specific to rural practice. Further work is necessary to clarify the improvement of cardiovascular outcomes for rural residents.
Translation, Cross-Cultural Adaptation and Validation of the Myofascial Adhesions for Patients after Breast Cancer (MAP-BC) Evaluation Tool: Spanish Version
Authors: Casuso-Holgado María Jesús , Ostos-Díaz Beatriz , Muñoz-Fernández María Jesús
Published: April 2022

(1) Background: The Myofascial Adhesions for Patients after Breast Cancer (MAP-BC) evaluation tool is a quantitative measure for the evaluation of tissue adhesions in breast cancer patients. The aims of this study were to create a Spanish version of the MAP-BC and to test its convergent validity and responsiveness. (2) Methods: Translation and cross-cultural adaptation were performed in five phases according to international guidelines. For the analysis of the convergent validity and responsiveness, a sample of 77 patients after breast cancer surgery were analysed at two timepoints (T1: immediately after the stitches were taken out; T2: one month after surgery). The COSMIN (Consensus-based Standards for the selection of health status Measurement Instruments) guidelines and checklist were used to verify the whole adaptation and validation process. (3) Results: Translation and cross-cultural adaptation of the original English version resulted in an easily understandable Spanish version of the tool. A moderate convergent validity (r = 0.438) with the Patient and Observer Scar Assessment (POSAS) at T1 and a strong correlation at T2 (r = 0.816) were observed. A moderate standardised response mean (0.45) and effect size (0.63) were also observed. (4) Conclusions: The MAP-BC Spanish version is a useful tool that could be incorporated into the evaluation of scars and surrounding tissues in breast cancer patients. It has shown a moderate convergent validity and responsiveness.
Single-Cell RNA-Seq Analysis of Cells from Degenerating and Non-Degenerating Intervertebral Discs from the Same Individual Reveals New Biomarkers for Intervertebral Disc Degeneration
Authors: Cherif Hosni , Mannarino Matthew , Pacis Alain Sarabia , Ragoussis Jiannis , Rabau Oded , Ouellet Jean A. , Haglund Lisbet
Published: April 2022

In this study, we used single-cell transcriptomic analysis to identify new specific biomarkers for nucleus pulposus (NP) and inner annulus fibrosis (iAF) cells, and to define cell populations within non-degenerating (nD) and degenerating (D) human intervertebral discs (IVD) of the same individual. Cluster analysis based on differential gene expression delineated 14 cell clusters. Gene expression profiles at single-cell resolution revealed the potential functional differences linked to degeneration, and among NP and iAF subpopulations. GO and KEGG analyses discovered molecular functions, biological processes, and transcription factors linked to cell type and degeneration state. We propose two lists of biomarkers, one as specific cell type, including C2orf40, MGP, MSMP, CD44, EIF1, LGALS1, RGCC, EPYC, HILPDA, ACAN, MT1F, CHI3L1, ID1, ID3 and TMED2. The second list proposes predictive IVD degeneration genes, including MT1G, SPP1, HMGA1, FN1, FBXO2, SPARC, VIM, CTGF, MGST1, TAF1D, CAPS, SPTSSB, S100A1, CHI3L2, PLA2G2A, TNRSF11B, FGFBP2, MGP, SLPI, DCN, MT-ND2, MTCYB, ADIRF, FRZB, CLEC3A, UPP1, S100A2, PRG4, COL2A1, SOD2 and MT2A. Protein and mRNA expression of MGST1, vimentin, SOD2 and SYF2 (p29) genes validated our scRNA-seq findings. Our data provide new insights into disc cells phenotypes and biomarkers of IVD degeneration that could improve diagnostic and therapeutic options.
Amorphous Inclusion Complexes: Molecular Interactions of Hesperidin and Hesperetin with HP-Β-CD and Their Biological Effects
Authors: Wdowiak Kamil , Rosiak Natalia , Tykarska Ewa , Żarowski Marcin , Płazińska Anita , Płaziński Wojciech , Cielecka-Piontek Judyta
Published: April 2022

This study aimed at obtaining hesperidin (Hed) and hesperetin (Het) systems with HP-β-CD by means of the solvent evaporation method. The produced systems were identified using infrared spectroscopy (FT-IR), X-ray powder diffraction (XRPD), and differential scanning calorimetry (DSC). Moreover, in silico docking and molecular dynamics studies were performed to assess the most preferable site of interactions between tested compounds and HP-β-CD. The changes of physicochemical properties (solubility, dissolution rate, and permeability) were determined chromatographically. The impact of modification on biological activity was tested in an antioxidant study as well as with regards to inhibition of enzymes important in pathogenesis of neurodegenerative diseases. The results indicated improvement in solubility over 1000 and 2000 times for Hed and Het, respectively. Permeability studies revealed that Hed has difficulties in crossing biological membranes, in contrast with Het, which can be considered to be well absorbed. The improved physicochemical properties influenced the biological activity in a positive manner by the increase in inhibitory activity on the DPPH radical and cholinoesterases. To conclude the use of HP-β-CD as a carrier in the formation of an amorphous inclusion complex seems to be a promising approach to improve the biological activity and bioavailability of Hed and Het.
Epigallocatechin Gallate Protects against Hypoxia-Induced Inflammation in Microglia via NF-κB Suppression and Nrf-2/HO-1 Activation
Authors: Kim So-Ra , Seong Kyung-Joo , Kim Won-Jae , Jung Ji-Yeon
Published: April 2022

Hypoxia-induced neuroinflammation in stroke, neonatal hypoxic encephalopathy, and other diseases subsequently contributes to neurological damage and neuronal diseases. Microglia are the primary neuroimmune cells that play a crucial role in cerebral inflammation. Epigallocatechin gallate (EGCG) has a protective antioxidant and anti-inflammatory effects against neuroinflammation. However, the effects of EGCG on hypoxia-induced inflammation in microglia and the underlying mechanism remain unclear. In this study, we investigated whether EGCG might have a protective effect against hypoxia injury in microglia by treatment with CoCl2 to establish a hypoxic model of BV2 microglia cells following EGCG pre-treatment. An exposure of cells to CoCl2 caused an increase in inflammatory mediator interleukin (IL)-6, inducible nitric oxide synthase (iNOS), and cyclooxygenase (COX)-2 expression, which were significantly ameliorated by EGCG via inhibition of NF-κB pathway. In addition, EGCG attenuated the expression of hypoxia-inducible factor (HIF)-1α and the generation of ROS in hypoxic BV2 cells. Furthermore, the suppression of hypoxia-induced IL-6 production by EGCG was mediated via the inhibition of HIF-1α expression and the suppression of ROS generation in BV2 cells. Notably, EGCG increased the Nrf-2 levels and HO-1 levels in the presence of CoCl2. Additionally, EGCG suppressed hypoxia-induced apoptosis of BV2 microglia with cleavage of poly (ADP-ribose) polymerase (PARP) and caspase-3. In summary, EGCG protects microglia from hypoxia-induced inflammation and oxidative stress via abrogating the NF-κB pathway as well as activating the Nrf-2/HO-1 pathway.
Synthesis and Biological Evaluation of Novel Bufalin Derivatives
Authors: Sampath VishnuPriya , Horesh Noa , Sasi Ben , Zannadeh Hiba , Pogodin Ilana , Singh Shiv Vardan , Deutsch Joseph , Lichtstein David
Published: April 2022

Bufalin and other cardiac steroids (CS) have been used for centuries for the treatment of congestive heart failure, arrhythmias, and other maladies. However, toxicity and the small therapeutic window of this family of steroids limit their use. Therefore, attempts to synthesize a potent, but less toxic, CS are of major importance. In the present study, two novel bufalin derivatives were synthesized and some of their pharmacological properties were characterized. The reaction of bufalin with Ishikawa’s reagent resulted in the production of two novel bufalin derivatives: bufalin 2,3-ene and bufalin 3,4-ene. The compounds were purified with TLC and HPLC and their structure was verified with UV, NMR, and MS analyses. The biological activities of these compounds were evaluated by testing their ability to inhibit the Na+, K+-ATPase activity of the brain microsomal fraction to induce cytotoxic activity against the NCI-60 human tumor cell line panel and non-cancer human cells, and to increase the force of contraction of quail embryonic heart muscle cells in culture. The two steroids exhibited biological activities similar to those of other CS in the tested experimental systems, but with reduced cytotoxicity, advocating their development as drugs for the treatment of heart failure and arrhythmias.
Development of a Multicolor 3D Printer Using a Novel Filament Shifting Mechanism
Authors: Thi Hai Van Nguyen , Phu Sinh Nguyen , Essomba Terence , Lai Jiing-Yih
Published: April 2022

Three-dimensional printing has become an unchallenged method for the manufacturing of complex shape objects. Although multicolor devices in Fuse Filament Feeder category recently have shown promising developments, their number still remains limited. The present study introduces the design of a new prototype of three-dimensional printer using Fused Filament Feeder and capable of printing multicolor objects. A single-color three-dimensional printer is used as a platform and is augmented for multicolor printing by the implementation of a mechatronic device that provides two functions. First, a transmission mechanism based on planetary gears allows feeding the selected filament color toward the printing head. The second function is provided by a combination of a central cam disk and several pushing rods. It allows selecting the filament color to be fed by the transmission system. The mechatronic device has been dimensioned to manage five different filament colors and the printing head has been modified to accommodate a five-to-one diamond nozzle. The filament shifting device is integrated into the single-color three-dimensional printer and a series of validation experiments has been carried out. These tests have demonstrated the new prototype ability to print out multicolor objects and to rival with commercial three-dimensional printers in terms of dimensional accuracy. This shows the ability of the proposed design and method to be used to upgrade a standard single-color 3D printer into a multicolor one. The presented multicolor 3D printer will be available to the 3D printing community for free.
Degenerative and Inflammatory Osteoproliferations in Lumbar Radiographs in Psoriatic Arthritis Patients
Authors: Ayan Gizem , Sadic Abdurrahman , Kilic Levent , Kalyoncu Umut
Published: April 2022

The aim of this study was to determine the distribution different types of osteoproliferative lesions on the lumbar spine and their relations in patients with psoriatic arthritis (PsA) under biologic-disease-modifying anti-rheumatic drug therapy. T12-S1 corners were evaluated in 182/274 (66.4%) patients with lumbar radiographs. Lesions were determined as osteophyte (grade 0–3), erosion, sclerosis, squaring, corner syndesmophyte, and bridging syndesmophyte. Lesions with no clear distinction were defined as ambiguous. The mean (SD) age of 182 PsA (69.2% female) patients was 47.6 years (12.7), the mean age at diagnosis of PsA was 39.7 years (12.7). Of the patients, 112 (61.5%) met the criteria for mNY. Osteophytes were the most frequently detected lesions (42.3%), with 18.1% of patients having osteophyte grade 2 and above (mostly on L2-L4). Syndesmophytes were present in 24.2% of all patients (mostly on T12-L4), and ambiguous lesions were detected in 13 (4.7%) patients. Changes were observed in five ambiguous lesions in patients with follow-up lumbar radiography, four of them transformed into corner syndesmophytes at follow-up, and one was evaluated as osteophyte grade 2. Approximately one fifth of patients presented with significant degenerative new bone formation, and syndesmophytes were found in one fourth. In approximately 7% of all patients, lesions were ambiguous. The nature of these lesions needs to be evaluated in further imaging studies.
Standardized Classification of Cerebral Vasospasm after Subarachnoid Hemorrhage by Digital Subtraction Angiography
Authors: Merkel Helena , Lindner Dirk , Gaber Khaled , Ziganshyna Svitlana , Jentzsch Jennifer , Mucha Simone , Gerhards Thilo , Sari Sabine , Stock Annika , Vothel Felicitas , Falter Lea , Quäschling Ulf , Hoffmann Karl-Titus , Meixensberger Jürgen , Halama Dirk , Richter Cindy
Published: April 2022

Background: During the last decade, cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) was a current research focus without a standardized classification in digital subtraction angiography (DSA). This study was performed to investigate a device-independent visual cerebral vasospasm classification for endovascular treatment. Methods: The analyses are DSA based rather than multimodal. Ten defined points of intracranial arteries were measured in 45 patients suffering from cerebral vasospasm after SAH at three time points (hospitalization, before spasmolysis, control after six months). Mathematical clustering of vessel diameters was performed to generate four objective grades for comparison. Six interventional neuroradiologists in two groups scored 237 DSAs after a new visual classification (grade 0–3) developed on a segmental pattern of vessel contraction. For the second group, a threshold-based criterion was amended. Results: The raters had a reproducibility of 68.4% in the first group and 75.2% in the second group. The complementary threshold-based criterion increased the reproducibility by about 6.8%, while the rating deviated more from the mathematical clustering in all grades. Conclusions: The proposed visual classification scheme of cerebral vasospasm is suitable as a standard grading procedure for endovascular treatment. There is no advantage of a threshold-based criterion that compensates for the effort involved. Automated vessel analysis is superior to compare inter-group results in research settings.
An Environmental-Adaptability-Improved RatSLAM Method Based on a Biological Vision Model
Authors: Wu Chong , Yu Shumei , Chen Liang , Sun Rongchuan
Published: April 2022

Inspired by rodents’ free navigation through a specific space, RatSLAM mimics the function of the rat hippocampus to establish an environmental model within which the agent localizes itself. However, RatSLAM suffers from the deficiencies of erroneous loop-closure detection, low reliability on the experience map, and weak adaptability to environmental changes, such as lighting variation. To enhance environmental adaptability, this paper proposes an improved algorithm based on the HSI (hue, saturation, intensity) color space, which is superior in handling the characteristics of image brightness and saturation from the perspective of a biological visual model. The proposed algorithm first converts the raw image data from the RGB (red, green, blue) space into the HSI color space using a geometry derivation method. Then, a homomorphic filter is adopted to act on the I (intensity) channel and weaken the influence of the light intensity. Finally, guided filtering is used to process the S (saturation) channel and improve the significance of image details. The experimental results reveal that the improved RatSLAM model is superior to the original method in terms of the accuracy of visual template matching and robustness.
Enhanced Parallel Sine Cosine Algorithm for Constrained and Unconstrained Optimization
Authors: Belazi Akram , Migallón Héctor , Gónzalez-Sánchez Daniel , Gónzalez-García Jorge , Jimeno-Morenilla Antonio , Sánchez-Romero José-Luis
Published: April 2022

The sine cosine algorithm’s main idea is the sine and cosine-based vacillation outwards or towards the best solution. The first main contribution of this paper proposes an enhanced version of the SCA algorithm called as ESCA algorithm. The supremacy of the proposed algorithm over a set of state-of-the-art algorithms in terms of solution accuracy and convergence speed will be demonstrated by experimental tests. When these algorithms are transferred to the business sector, they must meet time requirements dependent on the industrial process. If these temporal requirements are not met, an efficient solution is to speed them up by designing parallel algorithms. The second major contribution of this work is the design of several parallel algorithms for efficiently exploiting current multicore processor architectures. First, one-level synchronous and asynchronous parallel ESCA algorithms are designed. They have two favors; retain the proposed algorithm’s behavior and provide excellent parallel performance by combining coarse-grained parallelism with fine-grained parallelism. Moreover, the parallel scalability of the proposed algorithms is further improved by employing a two-level parallel strategy. Indeed, the experimental results suggest that the one-level parallel ESCA algorithms reduce the computing time, on average, by 87.4% and 90.8%, respectively, using 12 physical processing cores. The two-level parallel algorithms provide extra reductions of the computing time by 91.4%, 93.1%, and 94.5% with 16, 20, and 24 processing cores, including physical and logical cores. Comparison analysis is carried out on 30 unconstrained benchmark functions and three challenging engineering design problems. The experimental outcomes show that the proposed ESCA algorithm behaves outstandingly well in terms of exploration and exploitation behaviors, local optima avoidance, and convergence speed toward the optimum. The overall performance of the proposed algorithm is statistically validated using three non-parametric statistical tests, namely Friedman, Friedman aligned, and Quade tests.
Dynamics Modeling of Industrial Robotic Manipulators: A Machine Learning Approach Based on Synthetic Data
Authors: Baressi Šegota Sandi , Anđelić Nikola , Šercer Mario , Meštrić Hrvoje
Published: April 2022

Obtaining a dynamic model of the robotic manipulator is a complex task. With the growing application of machine learning (ML) approaches in modern robotics, a question arises of using ML for dynamic modeling. Still, due to the large amounts of data necessary for this approach, data collection may be time and resource-intensive. For this reason, this paper aims to research the possibility of synthetic dataset creation by using pre-existing dynamic models to test the possibilities of both applications of such synthetic datasets, as well as modeling the dynamics of an industrial manipulator using ML. Authors generate the dataset consisting of 20,000 data points and train seven separate multilayer perceptron (MLP) artificial neural networks (ANN)—one for each joint of the manipulator and one for the total torque—using randomized search (RS) for hyperparameter tuning. Additional MLP is trained for the total torsion of the entire manipulator using the same approach. Each model is evaluated using the coefficient of determination (R2) and mean absolute percentage error (MAPE), with 10-fold cross-validation applied. With these settings, all individual joint torque models achieved R2 scores higher than 0.9, with the models for first four joints achieving scores above 0.95. Furthermore, all models for all individual joints achieve MAPE lower than 2%. The model for the total torque of all joints of the robotic manipulator achieves weaker regression scores, with the R2 score of 0.89 and MAPE slightly higher than 2%. The results show that the torsion models of each individual joint, and of the entire manipulator, can be regressed using the described method, with satisfactory accuracy.
Study on the Interaction between Serum Thyrotropin and Semen Parameters in Men
Authors: Kakoulidis Ioannis , Ilias Ioannis , Stergiotis Stefanos , Togias Stefanos , Michou Aikaterini , Lekkou Anastasia , Mastrodimou Vasiliki , Pappa Athina , Milionis Charalampos , Venaki Evangelia , Koukkou Eftychia
Published: April 2022

The effect of thyroid function on semen parameters has been studied in pathological conditions in small studies. With this research work, we aimed to study thyroid hormone effects on semen parameters in 130 men who were evaluated for couple subfertility. Our study was cross-sectional. We noted semen volume, sperm concentration, total sperm count, testosterone levels and thyrotropin (TSH) levels. The analysis included ordinary least squares regression (OLS-R), quantile regression (QR) and segmented line regression (SR). Using OLS-R, a weak negative correlation was found between the logTSH levels and semen volume (r = −0.16, r2 = 0.03, p = 0.05). In Q-R, each incremental unit increase in logTSH decreased the mean semen volume between −0.78 ± 0.44 and −1.33 ± 0.34 mL (40–60th response quantile) and between −1.19 ± 0.71 and −0.61 ± 0.31 mL (70–90th response quantile) (p = 0.049). With SR, a biphasic relationship of sperm concentration with TSH was noted (positive turning to negative, peaking at TSH = 1.22 μIU/mL). Thus, a weak negative association between the TSH levels and semen volume was noted, showing a trough within the usual normal range for TSH. Moreover, a biphasic relationship between the sperm concentration and TSH was also noted, peaking at approximately mid-normal TSH levels. Based on our results, TSH explained slightly less than 3% of the variation in semen volume and 7% of the sperm concentration (thus, other factors, which were not studied here, have a more important effect on it).
Hydra’s Lasting Partnership with Microbes: The Key for Escaping Senescence?
Authors: He Jinru , Bosch Thomas C. G.
Published: April 2022

Aging results from a complex interplay between genetic endowment and environmental exposures during lifetime. As our understanding of the aging process progresses, so does the need for experimental animal models that allow a mechanistic understanding of the genetic and environmental factors involved. One such well-studied animal model is the freshwater polyp Hydra. Hydra are remarkable because they are non-senescent. Much of this non-senescence can be ascribed to a tissue consisting of stem cells with continuous self-renewal capacity. Another important fact is that Hydra’s ectodermal epithelial surface is densely colonized by a stable multispecies bacterial community. The symbiotic partnership is driven by interactions among the microbiota and the host. Here, we review key advances over the last decade that are deepening our understanding of the genetic and environmental factors contributing to Hydra’s non-senescent lifestyle. We conclude that the microbiome prevents pathobiont invasion (colonization resistance) and stabilizes the patterning mechanisms, and that microbiome malfunction negatively affects Hydra’s continuous self-renewal capacity.
Photoacoustic Effect of Near-Infrared Absorbing Organic Molecules via Click Chemistry
Authors: Zhu Wenqing , Miao Zongcheng , Chu Yaqin , Li Liaoliao , Wang Lei , Wang Dong
Published: April 2022

Near-infrared dyes were developed to be contrast agents due to their ability to improve the productivity of photoacoustic (PA) imaging and photothermal therapy (PTT) treatments. During the article, we described in detail the PA and PT effects of a category of organic molecules. F4-TCNQ could potentially cause a red-shift in the peak PA intensity. The results show that the PTT intensity of the near-infrared dyes with phenyl groups were higher than near-infrared dyes with thiophene groups. We also investigated the photodynamic treatment effect of C1b to demonstrate that these dyes are highly desirable in biochemistry. The high photoacoustic intensity of the organic molecules and the good yield of reactive oxygen species could indicate that these dyes have good potential for a wide range of imaging applications. Finally, we embedded the dye (C1b) in a liposomal hydrophobic phospholipid bilayer (C1b⊂L) to facilitate the application of hydrophobic dyes in biomedical applications, which can be absorbed by cells with good compatible and high stability for the imaging of cellular PA.
Revisiting the Rate-Dependent Mechanical Response of Typical Silicon Structures via Molecular Dynamics
Authors: Liu Yi , Wan Wei , Li Quan , Xiong Zhenkang , Tang Changxin , Zhou Lang
Published: April 2022

Strain rate is a critical parameter in the mechanical application of nano-devices. A comparative atomistic study on both perfect monocrystalline silicon crystal and silicon nanowire was performed to investigate how the strain rate affects the mechanical response of these silicon structures. Using a rate response model, the strain rate sensitivity and the critical strain rate of two structures were given. The rate-dependent dislocation activities in the fracture process were also discussed, from which the dislocation nucleation and motion were found to play an important role in the low strain rate deformations. Finally, through the comparison of five equivalent stresses, the von Mises stress was verified as a robust yield criterion of the two silicon structures under the strain rate effects.
Application of Liquid Chromatography Coupled to Mass Spectrometry in Quality Assessment of Dietary Supplements—A Case Study of Tryptophan Supplements: Release Assay, Targeted and Untargeted Studies
Authors: Stępień Krzysztof Adam , Giebułtowicz Joanna
Published: April 2022

Dietary supplements are widely consumed in the EU and the USA. Based on their similarity to pharmaceuticals, consumers mistakenly believe that dietary supplements have also been approved for safety and efficacy. However, in the absence of mandatory testing, data on supplement quality is scarce. Thus, we applied liquid chromatography coupled with tandem mass spectrometry to analyse the quality of dietary supplements containing tryptophan (Trp). We examined 22 supplements in tablets or capsules, produced in the USA, Great Britain, Germany, France, Czech Republic, and Poland. Trp release, crucial for bioavailability and efficiency, was assessed. Additionally, we performed a qualitative analysis of the main ingredient and screened for contaminants. Among the contaminants, we detected Trp’s metabolites, condensation products of Trp and carbonyl compounds, Trp degradation products, degradation products of kynurenine, and other contaminants such as glucosamine and melatonin. The main ingredient content was in the range of 55–100% in capsules and 69–87% in tablets. Surprisingly, almost no Trp release was noted from some supplements. Our study confirms the need to advance research on supplements. We believe that the high-quality analysis of supplements based on reliable analytical techniques will be an important contribution to the discussion on the regulatory framework of these products.
Abiotic Factors from Different Ecuadorian Regions and Their Contribution to Antioxidant, Metabolomic and Organoleptic Quality of Theobroma cacao L. Beans, Variety “Arriba Nacional”
Authors: Mihai Raluca A. , Landazuri Abarca Pablo A. , Tinizaray Romero Bryan A. , Florescu Larisa I. , Catană Rodica , Kosakyan Anush
Published: April 2022

Fine flavor cocoa is a unique category of cocoa that produces almonds with high aromatic potential and several sensory benefits that make it different from the basic or ordinary cocoas. Ecuador is the world’s leader in the production and export of fine flavor cocoa, responsible for 63% of the world’s total production due to the commercialization of the Arriba Nacional variety, known to possess an intense aroma that is unique in the cocoa world market. Besides its organoleptic specificity, this variety represents a source of important bioactive compounds associated with both sensory and health properties. This study evaluates the influence of an abiotic factor, nutritional soil status, on the phytochemical composition (methylxantines and phenolic compounds), and antioxidant and sensory properties of Arriba variety cocoa beans originating from three different geographical regions of Ecuador. We used the Diagnosis and Recommendation Integrated System (DRIS), Folin–Ciocalteau, high-performance liquid chromatography (HPLC), ABTS free-radical-scavenging activity, the α, α-diphenyl-β-picrylhydrazyl free-radical-scavenging method (DPPH), and Ferric reducing antioxidant power (FRAP) analysis to reveal a significant correlation between Mn ions and total phenolic content, a positive implication of N in methylxanthine composition and antioxidant properties, and the importance of Ca, Mg, and K ions in increasing the flavonoid and anthocyanin content of raw cocoa beans. We showed that these nutritional elements can interfere with the nutraceutical and sensory properties of cocoa beans, as Cu, Mg, and K are correlated with anthocyaninic content, while Fe, Ca, P and Zn influenced the flavonoid content. We underline that the Arriba variety is suitable not only for the production of high-quality chocolate, but also for the increasing worldwide nutraceutical market, generating qualitative and competitive products.
Specific Roles of Lipoxygenases in Development and Responses to Stress in Plants
Authors: Singh Priyanka , Arif Yamshi , Miszczuk Edyta , Bajguz Andrzej , Hayat Shamsul
Published: April 2022

Lipoxygenases (LOXs), naturally occurring enzymes, are widely distributed in plants and animals. LOXs can be non-sulfur iron, non-heme iron, or manganese-containing dioxygenase redox enzymes. LOXs catalyze the oxidation of polyunsaturated fatty acids into fatty acid hydroperoxides. Linolenic acid, a precursor in the jasmonic acid (JA) biosynthesis, is converted to 12-oxo-phytodienoic acid through oxygenation with LOX, allene oxide synthase, and allene oxide cyclase. Moreover, JA participates in seed germination, fruit ripening, senescence, and many other physio-biochemical processes. LOXs also play crucial roles in defense responses against biotic stress, i.e., insects, pests, pathogenic attacks, and abiotic stress, such as wounding, UV-rays, extreme temperature, oxidative stress, and drought.