bluuebunny/crossref_metadata_2025 huggingface dataset:
Potential Utility of Neurosonology in Paroxysmal Atrial Fibrillation Detection in Patients with Cryptogenic Stroke
Authors: Liantinioti Chrissoula , Palaiodimou Lina , Tympas Konstantinos , Parissis John , Theodorou Aikaterini , Ikonomidis Ignatios , Chondrogianni Maria , Zompola Christina , Triantafyllou Sokratis , Roussopoulou Andromachi , Kargiotis Odysseas , Serdari Aspasia , Bonakis Anastasios , Vadikolias Konstantinos , Voumvourakis Konstantinos , Stefanis Leonidas , Filippatos Gerasimos , Tsivgoulis Georgios
Published: November 2019

Background: Occult paroxysmal atrial fibrillation (PAF) is a common and potential treatable cause of cryptogenic stroke (CS). We sought to prospectively identify independent predictors of atrial fibrillation (AF) detection in patients with CS and sinus rhythm on baseline electrocardiogram (ECG), without prior AF history. We had hypothesized that cardiac arrhythmia detection during neurosonology examinations (Carotid Duplex (CDU) and Transcranial Doppler (TCD)) may be associated with higher likelihood of AF detection. Methods: Consecutive CS patients were prospectively evaluated over a six-year period. Demographics, clinical and imaging characteristics of cerebral ischemia were documented. The presence of arrhythmia during spectral waveform analysis of CDU/TCD was recorded. Left atrial enlargement was documented during echocardiography using standard definitions. The outcome event of interest included PAF detection on outpatient 24-h Holter ECG recordings. Statistical analyses were performed using univariate and multivariate logistic regression models. Results: A total of 373 patients with CS were evaluated (mean age 60 ± 11 years, 67% men, median NIHSS-score 4 points). The rate of PAF detection of any duration on Holter ECG recordings was 11% (95% CI 8%–14%). The following three variables were independently associated with the likelihood of AF detection on 24-h Holter-ECG recordings in both multivariate analyses adjusting for potential confounders: age (OR per 10-year increase: 1.68; 95% CI: 1.19–2.37; p = 0.003), moderate or severe left atrial enlargement (OR: 4.81; 95% CI: 1.77–13.03; p = 0.002) and arrhythmia detection during neurosonology evaluations (OR: 3.09; 95% CI: 1.47–6.48; p = 0.003). Conclusion: Our findings underline the potential utility of neurosonology in improving the detection rate of PAF in patients with CS.
Systematic Review of the Role of Biomarkers in Predicting Anastomotic Leakage Following Gastroesophageal Cancer Surgery
Authors: de Mooij Cornelis Maarten , Maassen van den Brink Martijn , Merry Audrey , Tweed Thais , Stoot Jan
Published: November 2019

Anastomotic leakage (AL) following gastroesophageal cancer surgery remains a serious postoperative complication. This systematic review aims to provide an overview of investigated biomarkers for the early detection of AL following esophagectomy, esophagogastrectomy and gastrectomy. All published studies evaluating the diagnostic accuracy of biomarkers predicting AL following gastroesophageal resection for cancer were included. The Embase, Medline, Cochrane Library, PubMed and Web of Science databases were searched. Risk of bias and applicability were assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) 2 tool. Twenty-four studies evaluated biomarkers in the context of AL following gastroesophageal cancer surgery. Biomarkers were derived from the systemic circulation, mediastinal and peritoneal drains, urine and mediastinal microdialysis. The most commonly evaluated serum biomarkers were C-reactive protein and leucocytes. Both proved to be useful markers for excluding AL owing to its high specificity and negative predictive values. Amylase was the most commonly evaluated peritoneal drain biomarker and significantly elevated levels can predict AL in the early postoperative period. The associated area under the receiver operating characteristic (AUROC) curve values ranged from 0.482 to 0.994. Current biomarkers are poor predictors of AL after gastroesophageal cancer surgery owing to insufficient sensitivity and positive predictive value. Further research is needed to identify better diagnostic tools to predict AL.
Seizures Do Not Affect Disability and Mortality Outcomes of Stroke: A Population-Based Study
Authors: Merlino Giovanni , Gigli Gian Luigi , Bax Francesco , Serafini Anna , Corazza Elisa , Valente Mariarosaria
Published: November 2019

Although seizures are frequently seen after cerebrovascular accidents, their effects on long-term outcome in stroke patients are still unknown. Therefore, the aim of this study was to investigate the relationship between post-stroke seizures and the risk of long-term disability and mortality in stroke patients. This study is part of a larger population-based study. All patients were prospectively followed up by a face-to-face interview or a structured telephone interview. We enrolled 635 patients with first-ever stroke and without a history of seizures. Prevalence of ischemic stroke (IS) was 85.2%, while the remaining 14.8% of patients were affected by intracerebral hemorrhage (ICH). During the study period, 51 subjects (8%) developed post-stroke seizures. Patients with post-stroke seizures were younger, had a higher prevalence of ICH, had a more severe stroke at admission, were more likely to have an IS involving the total anterior circulation, and were more likely to have a lobar ICH than patients without seizures. Moreover, subjects with seizures had more frequently hemorrhagic transformation after IS and cortical strokes. At 24 months, the risk of disability in patients with seizures was almost twice than in those without seizures. However, the negative effect of seizures disappeared in multivariate analysis. Kaplan-Meier survival curves at 12 years were not significantly different between patients with and without post-stroke seizures. Using the Cox multivariate analysis, age, NIHSS at admission, and pre-stroke mRS were independently associated with all-cause long-term mortality. In our sample, seizures did not impair long-term outcome in patients affected by cerebrovascular accidents. The not significant, slight difference in favor of a better survival for patients with seizures may be attributed to the slight age difference between the two groups.
Pulsed Electromagnetic Field Therapy Improves Osseous Consolidation after High Tibial Osteotomy in Elderly Patients—A Randomized, Placebo-Controlled, Double-Blind Trial
Authors: Ziegler Patrick , Nussler Andreas K. , Wilbrand Benjamin , Falldorf Karsten , Springer Fabian , Fentz Anne-Kristin , Eschenburg Georg , Ziegler Andreas , Stöckle Ulrich , Maurer Elke , Ateschrang Atesch , Schröter Steffen , Ehnert Sabrina
Published: November 2019

Extremely low-frequency pulsed electromagnetic field (ELF-PEMF) therapy is proposed to support bone healing after injuries and surgical procedures, being of special interest for elderly patients. This study aimed at investigating the effect of a specific ELF-PEMF, recently identified to support osteoblast function in vitro, on bone healing after high tibial osteotomy (HTO). Patients who underwent HTO were randomized to ELF-PEMF or placebo treatment, both applied by optically identical external devices 7 min per day for 30 days following surgery. Osseous consolidation was evaluated by post-surgical X-rays (7 and 14 weeks). Serum markers were quantified by ELISA. Data were compared by a two-sided t-test (α = 0.05). Device readouts showed excellent therapy compliance. Baseline parameters, including age, sex, body mass index, wedge height and blood cell count, were comparable between both groups. X-rays revealed faster osseous consolidation for ELF-PEMF compared to placebo treatment, which was significant in patients ≥50 years (∆mean = 0.68%/week; p = 0.003). Findings are supported by post-surgically increased bone-specific alkaline phosphatase serum levels following ELF-PEMF, compared to placebo (∆mean = 2.2 µg/L; p = 0.029) treatment. Adverse device effects were not reported. ELF-PEMF treatment showed a tendency to accelerate osseous consolidation after HTO. This effect was stronger and more significant for patients ≥50 years. This ELF-PEMF treatment might represent a promising adjunct to conventional therapy supporting osseous consolidation in elderly patients. Level of Evidence: I.
Geographic Differences in Phenotype and Treatment of Children with Sickle Cell Anemia from the Multinational DOVE Study
Authors: Inusa Baba Psalm Duniya , Colombatti Raffaella , Rees David C. , Heeney Matthew M. , Hoppe Carolyn C. , Ogutu Bernhards , Hassab Hoda M. , Zhou Chunmei , Yao Suqin , Brown Patricia B. , Heath Lori E. , Jakubowski Joseph A. , Abboud Miguel R.
Published: November 2019

Background: DOVE (Determining Effects of Platelet Inhibition on Vaso-Occlusive Events) was a Phase 3, randomized, double-blind, placebo-controlled study conducted in children with sickle cell anemia at 51 sites in 13 countries across four continents. Procedure: Data from DOVE were assessed for regional differences in subject phenotype and treatment. Demographics, baseline clinical and laboratory data, hydroxyurea (HU) use, vaso-occlusive crisis (VOCs; composite endpoint of painful crisis or acute chest syndrome (ACS)), serious adverse events (SAEs), hospitalization, and treatments were compared across the Americas, Europe, North Africa/Middle East, and Sub-Saharan Africa (SSA). Results: Race, body mass index, and blood pressures differed by region. Pre-enrollment VOCs were highest in the Americas. For subjects not on HU, baseline hemoglobin was lowest in SSA; reticulocyte count was lowest in the Americas. Within SSA, Kenya subjects presented higher baseline hemolysis. Painful crisis was the most common SAE, followed by ACS in the Americas and infections in other regions. VOC rate and percentage of VOC hospitalizations were highest in Europe. Regardless of region, most VOCs were treated with analgesics; approximately half were treated with intravenous fluids. The proportion of VOC-related transfusions was greatest in Europe. Lengths of hospital stay were similar across regions. Conclusions: Overall differences in SAEs and hospitalization for VOCs may be due to cultural diversities, resource utilization, disease severity, or a combination of factors. These data are of importance for the planning of future trials in SCA in a multinational setting.
Association between Sleep Duration and Subclinical Thyroid Dysfunction Based on Nationally Representative Data
Authors: Kim Woojun , Lee Jeongmin , Ha Jeonghoon , Jo Kwanhoon , Lim Dong-Jun , Lee Jung-Min , Chang Sang-Ah , Kang Moo-Il , Kim Min-Hee
Published: November 2019

Background: Sleep duration is an identified risk factor for adverse health outcomes. As the endocrine system is closely intertwined with sleep duration and quality, the association between endocrine dysfunction and sleep has been evaluated. Thyroid function, particularly that related to thyrotropin (TSH), is also known to be influenced by the sleep/awake status and circadian rhythm. Additionally, a link between sleep duration and autoimmunity, which is a common cause of thyroid dysfunction, has been suggested; however, depending on the sleep deprivation method used in studies, the effects of sleep on thyroid function vary. The relationship between subclinical thyroid dysfunction and sleep duration is poorly documented. Thus, to elucidate the impact of sleep on thyroid function, we investigated the association of subclinical thyroid dysfunction with sleep duration using representative data from the sixth Korea National Health and Nutrition Examination Survey, conducted from 2013 to 2015. Methods: In all, 4945 participants (2543 male and 2402 female) were included after excluding subjects using the following criteria: <19 years of age, free T4 level outside the normal range, history of thyroid disease, or incomplete data. The population was classified into three groups: short sleeper (<7 h/day), normal sleeper (7–8 h/day), and long sleeper (>8 h/day). The odds ratio (OR) for subclinical hypothyroidism or hyperthyroidism according to sleep duration was evaluated. Results: The short, normal, and long sleeper groups consisted of 2097, 2514, and 334 subjects, respectively. On multiple logistic regression analysis, compared to normal sleepers, short sleepers showed a significantly increased risk of subclinical hyperthyroidism (OR 1.37, 95% confidential interval (CI) 1.02–1.84, p = 0.036), while the risk of subclinical hypothyroidism in short sleepers was not elevated. Comparing long sleepers to normal sleepers, the OR for subclinical hyperthyroidism and hypothyroidism was 1.79 (95% CI 1.12–2.86, p = 0.015) and 1.91 (95% CI 1.03–3.53, p = 0.039), respectively. Conclusions: Both shorter and longer sleep durations were associated with an increase in the risk of subclinical thyroid dysfunction compared to the optimal sleep duration. This analysis of representative population data shows that sleep duration could intertwine with thyroid function resulting in increased risk of subclinical thyroid dysfunction.
Combined Effects of MMP-7, MMP-8 and MMP-26 on the Risk of Ischemic Stroke
Authors: Hsieh Fang-I , Chiou Hung-Yi , Hu Chaur-Jong , Jeng Jiann-Shing , Lin Huey-Juan , Lee Jiunn-Tay , Lien Li-Ming
Published: November 2019

Ischemic stroke (IS) is multifactorial causation combining with traditional cardiovascular disease (CVD) and genetic risk factors. Combined effects of MMP-7, MMP-8 and MMP-26 on the risk of IS remain incompletely understood. We aimed to assess individual and joint effects for IS risk by weighted genetic risk score (wGRS) from these three genes and traditional CVD risk factors. A case-control study including 500 cases with IS and 500 stroke-free healthy controls frequency-matched with cases by age and sex was conducted. The wGRS was a weighted average of the number of risk genotype across selected SNPs from MMP-7, MMP-8 and MMP-26. Multivariate logistic regression models were used to analyze the relationship between wGRS and risk of IS. A wGRS in the second tertile was associated with a 1.5-fold increased risk of IS compared with the lowest tertile after adjusting for traditional CVD risk factors. Compared to subjects with low genetic and low modifiable CVD risk, those with high genetic and high modifiable CVD risk had the highest risk of IS (adjusted-OR = 5.75). In conclusion, higher wGRS was significantly associated with an increased risk for IS. A significant interaction between genetic and traditional CVD risk factors was also found on the risk of IS.
Systemic Lidocaine Infusion for Post-Operative Analgesia in Children Undergoing Laparoscopic Inguinal Hernia Repair: A Randomized Double-Blind Controlled Trial
Authors: Lee Hye-Mi , Choi Kwan-Woong , Byon Hyo-Jin , Lee Ji-Min , Lee Jeong-Rim
Published: November 2019

Systemic lidocaine can provide satisfactory post-operative analgesia in adults. In this study, we assessed whether intravenous lidocaine is effective for post-operative analgesia and recovery in children undergoing laparoscopic inguinal hernia repair. A total of 66 children aged from six months to less than six years were classified in either the lidocaine (L) or control (C) groups. Children in Group L received a lidocaine infusion (a bolus dose of 1 mL kg−1, followed by a 1.5 mg kg−1 h−1 infusion), whereas Group C received the same volume of 0.9% saline. The primary outcome was the number of patients who presented face, legs, activity, crying and consolability (FLACC) scores of four or more, and therefore received rescue analgesia in the post-anesthesia recovery care unit (PACU). Secondary outcomes included the highest FLACC score in the PACU, FLACC, and the parents’ postoperative pain measure (PPPM) score at 48 h post-operation, as well as side effects. The number of children who received rescue analgesia in the PACU was 15 (50%) in Group L and 22 (73%) in Group C (p = 0.063). However, the highest FLACC score in PACU was lower in Group L (3.8 ± 2.4) than in Group C (5.3 ± 2.7) (p = 0.029). In conclusion, systemic lidocaine did not reduce the number of children who received rescue analgesia in PACU.
Intrinsic Cellular Responses of Human Wharton’s Jelly Mesenchymal Stem Cells Influenced by O2-Plasma-Modified and Unmodified Surface of Alkaline-Hydrolyzed 2D and 3D PCL Scaffolds
Authors: Inthanon Kewalin , Janvikul Wanida , Ongchai Siriwan , Chomdej Siriwadee
Published: November 2019

Polycaprolactone (PCL), a hydrophobic-degradable polyester, has been widely investigated and extensively developed, to increase the biocompatibility for tissue engineering. This research was the first trial to evaluate the intrinsic biological responses of human Wharton’s Jelly Mesenchymal Stem Cells (hWJMSCs) cultured on alkaline hydrolysis and low-pressure oxygen plasma modified 2D and 3D PCL scaffolds, without adding any differentiation inducers; this has not been reported before. Four types of the substrate were newly established: 2D plasma-treated PCL (2D-TP), 2D non-plasma-treated PCL (2D-NP), 3D plasma-treated PCL (3D-TP), and 3D non-plasma-treated PCL (3D-NP). Physicochemical characterization revealed that only plasma-treated PCL scaffolds significantly increased the hydrophilicity and % oxygen/carbon ratio on the surfaces. The RMS roughness of 3D was higher than 2D conformation, whilst the plasma-treated surfaces were rougher than the non-plasma treated ones. The cytocompatibility test demonstrated that the 2D PCLs enhanced the initial cell attachment in comparison to the 3Ds, indicated by a higher expression of focal adhesion kinase. Meanwhile, the 3Ds promoted cell proliferation and migration as evidence of higher cyclin-A expression and filopodial protrusion, respectively. The 3Ds potentially protected the cell from apoptosis/necrosis but also altered the pluripotency/differentiation-related gene expression. In summary, the different configuration and surface properties of PCL scaffolds displayed the significant potential and effectiveness for facilitating stem cell growth and differentiation in vitro. The cell–substrate interactions on modified surface PCL may provide some information which could be further applied in substrate architecture for stem cell accommodation in cell delivery system for tissue repair.
Transition of Collective Land in Modernistic Residential Settings in New Belgrade, Serbia
Authors: Milojević Milica P. , Maruna Marija , Djordjević Aleksandra
Published: November 2019

Turbulent periods of transition from socialism to neoliberal capitalism, which have affected the relationships between holders of power and governing structures in Serbia, have left a lasting impact on the urban spaces of Belgrade’s cityscape. The typical assumption is that the transformation of the urban form in the post-socialist transition is induced by planning interventions which serve to legitimize these neoliberal aspirations. The methodological approach of this paper is broadly structured as a chronological case analysis at three levels: the identification of three basic periods of institutional change, historical analysis of the urban policies that permitted transformation of the subject area, and morphogenesis of the selected site alongside the Sava River in New Belgrade. Neoliberal aspirations are traced through the moments of destruction and moments of creation as locally specific manifestations of neoliberal mechanisms observable through the urban form. Comparison of all three levels of the study traces how planning and political decisions have affected strategic directions of development and, consequently, the dynamics and spatial logic of how new structures have invaded the street frontage. The paper demonstrates that planning interventions in the post-socialist transition period, guided by the neoliberal mechanisms, has had a profound impact on the super-block morphology.
The Transition from Housing Demolition to Conservation and Renovation in Shanghai: Challenges and Countermeasures
Authors: Shi Jiangang , Min Xinru , Si Hongyun , Tang Daizhong , Miao Wei
Published: November 2019

In the past few decades, a considerable number of old houses have been demolished in China’s urban redevelopment projects, which led to the disappearance of some historic buildings and the relocation of the original residents. Recently, the strategy of housing demolition (HD) in Chinese cities has been replaced by housing conservation and renovation (HCR). However, the transition from HD to HCR is not carried out well. This study aims to explore the key challenges in HCR practice by using a mixed method. Based on the field investigations in pilot projects and semistructured interviews, current HCR practices in Shanghai are summarized, and the four key challenges are identified as: (1) funding shortages; (2) an underdeveloped regulatory environment; (3) a psychological gap between the government and residents; and (4) a lack of stakeholders’ involvement. Targeted measures are proposed to mitigate the challenges. The findings and suggestions here could provide valuable references for the government when making decisions on sustainable housing conservation and renovation, and may promote urban renewal practices in China and other developing countries.
Organisational Skills in Academic Writing: A Study on Coherence and Cohesion in Pakistani Research Abstracts
Authors: Ahmad Muhammad , Mahmood Muhammad Asim , Siddique Ali Raza
Published: November 2019

Writing requires a suitable and strategic use of language with communicative potential and structural correctness. The use of coherence and cohesion helps create communicative potential and structural correctness in texts. This study aims to investigate the use of cohesive items in the abstracts of Pakistani research articles and thereby determine what type of cohesive items are frequently used by writers. In addition, the study aims to know what functions the said writers achieve through the most frequently used cohesive items. For this purpose, 50 abstracts were retrieved from two famous Pakistani research journals (25 articles per journal), which were developed into a corpus for the study and analysed through AntConc. 3.4.4.0. The results revealed that Pakistani research writers used reference items the most frequently to achieve “directive” as well as “referential” functions. On the basis of these findings, the study concluded that Pakistani research article writers organised information in abstracts using reference items the most frequently and they were mainly concerned with directive as well as referential functions of meaning. The results also showed that the said writers organised texts on a syntactic level only, which implied that they should organise texts on a semantic level also. This would be possible with the use of repetition devices.
Arabic-Spanish Language Contact in Puerto Rico: A Case of Glottal Stop Epenthesis
Authors: Mohamed Sherez , González Carolina , Muntendam Antje
Published: November 2019

The current study examines the realization of adjacent vowels across word boundaries in Arabic-Spanish bilinguals and Spanish monolinguals in Puerto Rico, focusing specifically on the rate of glottal stop epenthesis in this context (e.g., hombre africano to [ˈom.bre.ʔa.fri.ˈka.no]). It was hypothesized that Arabic-Spanish bilinguals would show a higher rate of glottal stop epenthesis than Spanish monolinguals because of transfer from Arabic. In addition, we investigated the possible effects of stress, vowel height, language dominance and bilingual type on the rate of glottal stop epenthesis. Results from a reading task with 8 participants showed no significant difference in glottalization between bilinguals and monolinguals. For monolinguals, glottalization was significantly more likely when the first vowel was low or stressed; significant interactions between vowel height and stress were found for the bilingual group. Language dominance was a significant factor, with Arabic-dominant bilinguals glottalizing more than the Spanish-dominant bilinguals. In addition, early sequential bilinguals favored glottalization slightly more than simultaneous bilinguals, without reaching significance. Our data suggests some effects of syllable structure transfer from Arabic, particularly in Arabic-dominant participants. To our knowledge, our study is the first exploration of Arabic and Spanish in contact in Puerto Rico, and the first to acoustically examine the speech of Arabic-Spanish bilinguals.
Mesoscale Simulation to Study Constitutive Properties of TATB/F2314 PBX
Authors: Ge Siyu , Zhang Wenying , Sang Jian , Yuan Shuai , Lo Glenn V. , Dou Yusheng
Published: November 2019

Material Point Method (MPM) mesoscale simulation was used to study the constitutive relation of a polymer bonded explosive (PBX) consisting of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) and a fluorine polymer binder F2314. The stress-strain variations of the PBX were calculated for different temperatures and different porosities, and the results were found to be consistent with experimental observations. The stress-strain relations at different temperatures were used to develop the constitutive equation of the PBX by using numerical data fitting. Stress-strain data for different porosities were used to establish the constitutive equation by fitting the simulation data to an improved Hashion-Shtrikman model. The equation can be used to predict the shear modulus and bulk modulus of the PBX at different densities of the sample. The constitutive equations developed for TATB/F2314 PBX by MPM mesoscale simulation are important equations for the numerical simulations of the PBX at macroscale. The method presented in this study provides an alternative approach for studying the constitutive relations of PBX.
Microstructure Adjustment of Spherical Micro-samples for High-Throughput Analysis Using a Drop-on-Demand Droplet Generator
Authors: Imani Moqadam Saeedeh , Mädler Lutz , Ellendt Nils
Published: November 2019

High-throughput methods for the development of structural materials require samples which are comparable in geometric dimensions and microstructure. Molten metal droplet generators produce thousands of droplets and microspheres from specific alloys with very good reproducibility. In this study, droplet generation experiments were conducted with two alloys and their microstructure was analyzed regarding secondary dendrite arm spacing (SDAS) in order to determine cooling rates during solidification. A droplet cooling model was developed, and predictions showed good agreement with the experimental data. Finally, a sensitivity study was conducted using the validated model to identify critical process parameters which have great impact on the resulting microstructure and need to be well-controlled to achieve the desired reproducibility in microstructure.
Supercrystallography-Based Decoding of Structure and Driving Force of Nanocrystal Assembly
Authors: Huang Xin , Wang Zhongwu
Published: November 2019

Nanocrystal (NC) assembly appears as one promising method towards the controllable design and fabrication of advanced materials with desired property and functionality. The achievement of a “materials-by-design” requires not only a primary structural decoding of NC assembled supercrystal at a wide range of length scales, but also an improved understanding of the interactions and changeable roles of various driving forces over the course of nucleation and growth of NC superlattice. The recent invention of a synchrotron-based X-ray supercrystallographic approach makes it feasible to uncover the structural details of NC-assembled supercrystal at unprecedented levels from atomic through nano to mesoscale. Such structural documentations can be used to trace how various driving forces interact in a competitive way and thus change relatively in strength to govern the formation of individual superlattices under certain circumstances. This short review makes use of four single supercrystals typically made up of spherical, truncate, cubic and octahedral NCs, respectively, and provides a comparable description and a reasonable analysis of the use of a synchrotron-based supercrystallographic approach to reveal various degrees of translational and orientational ordering of NCs within various superlattices. In the connection of observed structural aspects with controlled environments of NC assembly, we further address how various driving forces interact each other to develop relatively changeable roles upon variation of the NC shape to respond to the nucleation and growth of various superlattices. With the guidance of such gained insights, we provide additional examples to illustrate how realistic environments are designed into delicate control of NC assembly to achieve particular interactions between NCs towards harvesting superlattice with NC translational symmetry and atomically crystallographic orientation as desired.
Modification of Bentonite with Cationic and Nonionic Surfactants: Structural and Textural Features
Authors: Andrunik Magdalena , Bajda Tomasz
Published: November 2019

Surfactant-modified clay minerals are known for their good sorption properties of both organic and inorganic compounds from aqueous solutions. However, the current knowledge regarding the effect of both cationic and nonionic surfactants on the properties of bentonite is still insufficient. Bentonite, with montmorillonite as the base clay, was modified with hexadecethyltrimethylammonium bromide (a cationic surfactant) in the amount of 1.0 cation exchange capacity (CEC) of bentonite and varying concentrations of t-octylphenoxypolyethoxyethanol (Triton X-100, a nonionic surfactant). We aimed to improve the understanding of the effect of nonionic and cationic surfactants on clay minerals. The modified bentonites were characterized by X-ray diffraction (XRD), thermogravimetric analysis/differential thermal analysis (TG/DTA), Fourier transform infrared spectrometry (FTIR), field emission scanning electron microscopy (SEM) and specific surface area and pore volume (BET). According to our results, the presence of a cationic surfactant significantly increased the amount of the adsorbed nonionic surfactant. Moreover, an increase in the concentration of nonionic surfactants is also associated with an increase in the effectiveness of the modification process. Our results indicate that the amount of nonionic surfactant used has a significant effect on the properties of the obtained hybrid material. Modification of bentonite with a nonionic surfactant did not cause an expansion of the interlayer space of smectite, regardless of the presence of a cationic surfactant. The modification process was found to significantly decrease the specific surface area of bentonite. Improvement of hydrophobic properties and thermal stability was also observed.
Study on Compatibility and Rheological Properties of High-Viscosity Modified Asphalt Prepared from Low-Grade Asphalt
Authors: Li Mingliang , Zeng Feng , Xu Ruigang , Cao Dongwei , Li Jun
Published: November 2019

High-viscosity modified asphalt is mainly used as a binder for porous asphalt in China and Japan. In order to meet the demand for using porous asphalt under high temperature condition in Africa, high-viscosity asphalt made from low-grade matrix asphalt, which is commonly used in Africa is investigated. Based on simulation of local climate in Africa, the suitable range of high viscosity additive content for different matrix asphalt was obtained by analyzing dynamic viscosity of the asphalt. Through PG high temperature grading, multi-stress repeated creep, accelerated fatigue, temperature sweep and other tests, changes of high temperature, anti-fatigue and anti-shear indicators before and after modification were compared and analyzed and effects of different matrix asphalt were also studied. Finally, considering engineering requirements, mixing and compaction temperatures of various high-viscosity modified asphalt were determined through study of viscosity-temperature characteristics. This research provides a support for preparation of high-viscosity modified asphalt and porous asphalt mixture by using low grade asphalt. The research achievements can help to guide the material design and application of porous asphalt in Africa and other high temperature areas.
Effects of a Chipboard Structure on Its Physical and Mechanical Properties
Authors: Mirski Radosław , Derkowski Adam , Dziurka Dorota , Dukarska Dorota , Czarnecki Rafał
Published: November 2019

The paper evaluated the possibility of manufacturing wood-based boards from the material left over from sawmill processing of wood. The boards were made from chips created during cant preparation for cutting and sawdust generated during further sawnwood preparation. They were made as one- and three-ply boards with face layers containing industrial microchips. Mechanical properties determined for one-ply boards in a bend test were used as guidelines for manufacturing three-ply boards. The outcomes were much better when the core layer comprised a mix of chips and sawdust than the chips alone. The study also showed that for the assumed technological parameters it is possible to produce three-ply boards with properties meeting the criteria for P2 furniture boards.
Fabrication and Finite Element Analysis of Composite Elbows
Authors: Qiao Tianlu , Zhang Guowei , Xu Yue , Zhang Boming
Published: November 2019

“Tube beams” are common lightweight structures, which have domestic and industry applications, and are often subjected to complex multidirectional loads. Therefore, metals with mature manufacturing methods and isotropic properties are commonly used in the fabrication of these structures, which are preferred to be lighter in weight. Although polymer matrix composites are generally used for weight reduction, their conventional manufacturing methods, such as pultrusion and filament-winding, cannot meet the isotropic requirements. Moreover, research on bent tube beams (elbows) is rare. Therefore, a self-made glass fiber/epoxy polyvinyl ester fabric prepreg and a self-designed mold were used in this study to prepare an isotropic composite double-bent elbow by a silicone rubber airbag-assisted process. The load capacity of the elbow was tested and validated by the finite element method. A strength and deformation of up to 3448 N and 2.84 mm respectively, were achieved. The simulation and experimental results were consistent: the error for the load capacity and deformation was only 4.15% and 7.75% respectively, under the max stress criterion.
Corrosion Behavior of an AISI/SAE Steel Cut by Electropulsing
Authors: Montilla Carlos Alberto , González Hernán Alberto , Kallewaard Valentina , Tristancho José Luis
Published: November 2019

The effect of electropulsing treatment (EPT) on the surface general corrosion behavior of an AISI/SAE 1045 steel under different machining regimes is studied. In the study, the following variables are alternated: high-speed steel (HSS) vs. hard metal (HM), and with and without the assistance of high-density electropulses. The corrosion rates are determined using comparative studies such as gravimetric analysis, salt spray chamber test, electrochemical polarization curve techniques (PC), and linear polarization resistance (LPR). Differences in surface microhardness were evaluated by applying optical microscopy and planimetric procedures. Specimens subjected to electropulses and turned with HM reported greater reductions of corrosion rates. Changes in corrosion behavior can be explained in terms of grain shape factor h variation. The present study demonstrates that electropulsing affects the corrosion behavior of AISI/SAE 1045 steel after the turning process.
Effect of Elastic Modulus on the Accuracy of the Finite Element Method in Simulating Precision Glass Molding
Authors: Yao Honghui , Lv Keyi , Zhang Jiarong , Wang Han , Xie Xiaozhu , Zhu Xiangyou , Deng Jiannan , Zhuo Shaomu
Published: November 2019

Precision glass molding is a revolutionary technology for achieving high precision and efficient manufacturing of glass aspheric lenses. The material properties of glass, including elastic modulus and viscosity, are highly dependent on temperature fluctuations. This paper aims to investigate the effect of elastic modulus on the high-temperature viscoelasticity of glass and the accuracy of the finite element simulation of the molding process for glass aspheric lenses. The high-temperature elastic modulus of D-ZK3L glass is experimentally measured and combined with the glass cylinder compression creep curve to calculate the high temperature viscoelasticity of D-ZK3L. Three groups of viscoelastic parameters are obtained. Based on this, the molding process of the molded aspheric lens is simulated by the nonlinear finite element method (FEM). The surface curves of lenses obtained by simulation and theoretical analyses are consistent. The simulation results obtained at different initial elastic modulus values indicate that the elastic modulus has a great influence on the precision of the FEM-based molding process of glass aspheric lenses.
Magnetic Particles-Based Analytical Platforms for Food Safety Monitoring
Authors: Khan Reem , Rehman Abdur , Hayat Akhtar , Andreescu Silvana
Published: November 2019

Magnetic nanoparticles (MNPs) have attracted growing interest as versatile materials for the development of analytical detection and separation platforms for food safety monitoring. This review discusses recent advances in the synthesis, functionalization and applications of MNPs in bioanalysis. A special emphasis is given to the use of MNPs as an immobilization support for biomolecules and as a target capture and pre-concentration to increase selectivity and sensitivity of analytical platforms for the monitoring of food contaminants. General principles and examples of MNP-based platforms for separation, amplification and detection of analytes of interest in food, including organic and inorganic constituents are discussed.
On ω-Limit Sets of Zadeh’s Extension of Nonautonomous Discrete Systems on an Interval
Authors: Su Guangwang , Sun Taixiang
Published: November 2019

Let I = [ 0 , 1 ] and f n be a sequence of continuous self-maps on I which converge uniformly to a self-map f on I. Denote by F ( I ) the set of fuzzy numbers on I, and denote by ( F ( I ) , f ^ ) and ( F ( I ) , f ^ n ) the Zadeh ′ s extensions of ( I , f ) and ( I , f n ) , respectively. In this paper, we study the ω -limit sets of ( F ( I ) , f ^ n ) and show that, if all periodic points of f are fixed points, then ω ( A , f ^ n ) ⊂ F ( f ^ ) for any A ∈ F ( I ) , where ω ( A , f ^ n ) is the ω -limit set of A under ( F ( I ) , f ^ n ) and F ( f ^ ) = { A ∈ F ( I ) : f ^ ( A ) = A } .
A New Fixed Point Theorem and a New Generalized Hyers-Ulam-Rassias Stability in Incomplete Normed Spaces
Authors: Ramezani Maryam , Ege Ozgur , De la Sen Manuel
Published: November 2019

In this study, our goal is to apply a new fixed point method to prove the Hyers-Ulam-Rassias stability of a quadratic functional equation in normed spaces which are not necessarily Banach spaces. The results of the present paper improve and extend some previous results.
Sine-Cosine Algorithm to Enhance Simulated Annealing for Unrelated Parallel Machine Scheduling with Setup Times
Authors: Jouhari Hamza , Lei Deming , A. A. Al-qaness Mohammed , Abd Elaziz Mohamed , Ewees Ahmed A. , Farouk Osama
Published: November 2019

This paper presents a hybrid method of Simulated Annealing (SA) algorithm and Sine Cosine Algorithm (SCA) to solve unrelated parallel machine scheduling problems (UPMSPs) with sequence-dependent and machine-dependent setup times. The proposed method, called SASCA, aims to improve the SA algorithm using the SCA as a local search method. The SCA provides a good tool for the SA to avoid getting stuck in a focal point and improving the convergence to an efficient solution. SASCA algorithm is used to solve UPMSPs by minimizing makespan. To evaluate the performance of SASCA, a set of experiments were performed using 30 tests for 4 problems. Moreover, the performance of the proposed method was compared with other meta-heuristic algorithms. The comparison results showed the superiority of SASCA over other methods in terms of performance dimensions.
Numerical Performance Evaluation of Solar Photovoltaic Water Pumping System under Partial Shading Condition using Modern Optimization
Authors: Arfaoui Jouda , Rezk Hegazy , Al-Dhaifallah Mujahed , Elyes Feki , Abdelkader Mami
Published: November 2019

Renewable energy is an attractive solution for water pumping systems particularly in isolated regions where the utility grid is unavailable. An attempt is made to improve the performance of solar photovoltaic water pumping system (SPVWPS) under partial shading condition. Under this condition, the power versus voltage curve has more than one maximum power point (MPP), which makes the tracking of global MPP not an easy task. Two MPP tracking (MPPT) strategies are proposed and compared for tracking MPP of SPVWPS under shading condition. The first method is based on the classical perturb and observe (P&O) and the other method is based on a Salp Swarm Algorithm (SSA). Based on extensive MATLAB simulation, it is found that the SSA method can provide higher photovoltaic (PV) generated power than the P&O method under shading condition. Consequently, the pump flowrate is increased. But, under normal distribution of solar radiation, both MPPT techniques can extract the maximum power but SSA is considered a time-consuming approach. Moreover, SSA is compared with particle swarm optimization (PSO) and genetic algorithm (GA). The obtained results ensure the superiority of SSA compared with PSO and GA. SSA has high successful rate of reaching true global MPP.
Analysis of Queueing System MMPP/M/K/K with Delayed Feedback
Authors: Melikov Agassi , Aliyeva Sevinj , Sztrik Janos
Published: November 2019

The model of multi-channel queuing system with Markov modulated Poisson process (MMPP) flow and delayed feedback is considered. After the customer is served completely, they will decide either to join the retrial group again for another service (feedback) with some state-dependent probability or to leave the system forever with complimentary probability. Feedback calls organize an orbit of repeated calls (r-calls). If upon arrival of an r-call all the channels of the system are busy, then it either leaves the system with some state-dependent probability or with a complementary probability returns to orbit. Methods to calculate the steady-state probabilities of the appropriate three-dimensional Markov chain as well as performance measures of investigated system are developed. Results of numerical experiments are demonstrated.
Optimizing the Maximal Perturbation in Point Sets while Preserving the Order Type
Authors: de la Fraga Luis Gerardo , Cruz Hernández Heriberto
Published: November 2019

Recently a new kind of fiducial marker based on order type (OT) has been proposed. Using OT one can unequivocally identify a set of points through its triples of point orientation, and therefore, there is no need to use metric information. These proposed order type tags (OTTs) are invariant under a projective transformation which allows identification of them directly from a photograph. The magnitude of noise in the point positions that a set of points can support without changing its OT, is named the maximal perturbation (MP) value. This value represents the maximal displacement that any point in the set can have in any direction without changing the triplet’s orientation in the set. A higher value of the MP makes an OTT instance more robust to perturbations in the points positions. In this paper, we address the problem of how to improve the MP value for sets of points. We optimize “by hand” the MP for all the 16 subsets of points in the set of OTs composed of six points, and we also propose a general algorithm to optimize all the sets of OTs composed of six, seven, and eight points. Finally, we show several OTTs with improved MP values, and their use in an augmented reality application.
Evaluation of Antifouling Potential and Ecotoxicity of Secondary Metabolites Derived from Red Algae of the Genus Laurencia
Authors: Protopapa Maria , Kotsiri Manto , Mouratidis Sofoklis , Roussis Vassilios , Ioannou Efstathia , Dedos Skarlatos G.
Published: November 2019

Red algae of the genus Laurencia are known to biosynthesize and secrete an immense variety of secondary metabolites possessing a spectrum of biological activities against bacteria, invertebrates and mammalian cell lines. Following a rigorous cross-species screening process, herein we report the antifouling potential of 25 secondary metabolites derived from species of the genus Laurencia, as well as the thorough evaluation of the ecotoxicity of selected metabolites against non-target marine arthropods and vertebrate cell lines. A number of these secondary metabolites exhibited potent antifouling activity and performed well in all screening tests. Our results show that perforenol (9) possesses similar antifouling activity with that already described for bromosphaerol, which is used herein as a benchmark.
The Effect of Mean Platelet Volume/Platelet Count Ratio on Dipper and Non-Dipper Blood Pressure Status
Authors: Meric Murat , Yuksel Serkan , Coksevim Metin , Gulel Okan
Published: November 2019

Background and Objectives: The mean platelet volume (MPV) represents a possible marker of platelet activation. There is an association between the platelet count (PC) and inflammation and platelet reactivity. We assessed the association between the MPV/PC ratio and circadian alterations in blood pressure (BP). Material and Methods: One hundred and twenty subjects in total, 80 hypertensive subjects and 40 healthy subjects (controls), were enrolled in the study group. Twenty four hour ambulatory BP monitoring (ABPM) was applied to all subjects. According to ABPM results, the hypertensive subjects were separated into two groups, such as dippers (n = 40) and non-dippers (n = 40). In all subjects, the collection of venous peripheral blood samples was performed on admission for PC and MPV measurements. Results: The two groups exhibited similar clinical baseline characteristics. A significantly higher MPV/PC ratio was determined in non-dippers compared to that in dippers and normotensives. The higher MPV/PC ratio was observed in non-dippers in comparison with that in dippers and normotensives (0.046 ± 0.007 to 0.032 ± 0.004 fL/[109/L]; 0.046 ± 0.007 to 0.026 ± 0.004 fL/[109/L], p < 0.001, respectively). A receiver operating characteristic (ROC) curve analysis showed that the optimum cut-off value of the MPV/PC ratio for predicting non-dipping patterns in hypertensive patients was 0.036 (area under the curve [AUC]: 0.98, p < 0.001). According to the cut-off value, sensitivity and specificity were found to be 95% and 95%, respectively. Conclusions: The higher MPV/PC ratio was determined in non-dipper hypertensive subjects in comparison with that in dipper hypertensive subjects. An elevation of platelet activity and an increase in thrombus burden are reflected by an increase in the MPV/PC ratio. The MPV/PC ratio may underlie the increase in cardiovascular risk in non-dippers compared to that in dippers.