bluuebunny/crossref_metadata_2025 huggingface dataset:
Tropical Cyclone Impacts on Headland Protected Bay
Authors: Wishaw Daniel , Leon Javier X. , Barnes Matthew , Fairweather Helen
Published: May 2020

The response of headland protected beaches to storm events is complex and strongly site dependent. In this study, we investigated the response of several headland protected beaches in Noosa, Australia to a tropical cyclone event. Pre and post topographical surveys of all beaches were completed using both pole-mounted RTK-GNSS and structure-from-motion (SfM)-derived elevation models from survey-grade drone imagery to assess sediment volume differentials. Coastal imaging was used to assess shoreline development and identify coastal features while a nearshore wave model (SWAN) was used to project waves into the study site from a regional wave buoy. Obliquely orientated swells drive currents along the headland with sediment being eroded from exposed sites and deposited at a protected site. Elevated sea-levels were shown to be a strong force-multiplier for relatively small significant wave heights, with 10,000 m3 of sediment eroded from a 700 m long beach in 36 h. The SWAN model was adequately calibrated for significant wave height, but refraction of swell around the headland was under-represented by an average of 16.48 degrees. This research has coastal management implications for beaches where development restricts natural shoreline retreat and elevated sea states are likely to become more common.
The Qualitative Characteristics of Accounting Information, Earnings Quality, and Islamic Banking Performance: Evidence from the Gulf Banking Sector
Authors: Elsiddig Ahmed Ibrahim
Published: May 2020

The study aims to operationalize financial reporting quality in terms of the qualitative characteristics (QCs) as stated by the Accounting and Auditing Organization of Islamic Financial Institutions (AAOIFI) standards, as well as to investigate their association with earnings quality (EQ) and banking performance. The study uses secondary data extracted from DataStream to operationalize and measure the financial reporting quality in the annual reports of 25 out of the 27 Islamic banks in the Gulf Council Countries (GCC) for a 5-year period (2014–2018), meaning 125 annual reports were used. The study applies a manual content analysis to the annual reports to score all the items of QCs and operationalizes 25 measurement items that represent the six QCs. All items use 5-point Likert-type scales to compute the sub-score and the overall index through the Neural Network System. The findings of the model paths show a significant positive relationship between EQ and most of the QCs. The first hypothesis is partially accepted as there is a positive relationship between EQ and relevancy, reliability, prudence and general quality; however, there is no significant relationship between EQ and understandability and there is a significant negative relationship between EQ and comparability. Moreover, the study finds a significant positive relationship between EQ and ROA on one hand and EQ and ROE on the other hand (p-value = 0.00), meaning the second hypothesis is supported.
State-of-the-Art Geospatial Information Processing in NoSQL Databases
Authors: Guo Dongming , Onstein Erling
Published: May 2020

Geospatial information has been indispensable for many application fields, including traffic planning, urban planning, and energy management. Geospatial data are mainly stored in relational databases that have been developed over several decades, and most geographic information applications are desktop applications. With the arrival of big data, geospatial information applications are also being modified into, e.g., mobile platforms and Geospatial Web Services, which require changeable data schemas, faster query response times, and more flexible scalability than traditional spatial relational databases currently have. To respond to these new requirements, NoSQL (Not only SQL) databases are now being adopted for geospatial data storage, management, and queries. This paper reviews state-of-the-art geospatial data processing in the 10 most popular NoSQL databases. We summarize the supported geometry objects, main geometry functions, spatial indexes, query languages, and data formats of these 10 NoSQL databases. Moreover, the pros and cons of these NoSQL databases are analyzed in terms of geospatial data processing. A literature review and analysis showed that current document databases may be more suitable for massive geospatial data processing than are other NoSQL databases due to their comprehensive support for geometry objects and data formats and their performance, geospatial functions, index methods, and academic development. However, depending on the application scenarios, graph databases, key-value, and wide column databases have their own advantages.
Visualizing When, Where, and How Fires Happen in U.S. Parks and Protected Areas
Authors: Inglis Nicole C. , Vukomanovic Jelena
Published: May 2020

Fire management in protected areas faces mounting obstacles as climate change alters disturbance regimes, resources are diverted to fighting wildfires, and more people live along the boundaries of parks. Evidence-based prescribed fire management and improved communication with stakeholders is vital to reducing fire risk while maintaining public trust. Numerous national fire databases document when and where natural, prescribed, and human-caused fires have occurred on public lands in the United States. However, these databases are incongruous and non-standardized, making it difficult to visualize spatiotemporal patterns of fire and engage stakeholders in decision-making. We created interactive decision analytics (“VISTAFiRe”) that transform fire history data into clear visualizations of the spatial and temporal dimensions of fire and its management. We demonstrate the utility of our approach using Big Cypress National Preserve and Everglades National Park as examples of protected areas experiencing fire regime change between 1980 and 2017. Our open source visualizations may be applied to any data from the National Park Service Wildland Fire Events Geodatabase, with flexibility to communicate shifts in fire regimes over time, such as the type of ignition, duration and magnitude, and changes in seasonal occurrence. Application of the tool to Everglades and Big Cypress revealed that natural wildfires are occurring earlier in the wildfire season, while human-caused and prescribed wildfires are becoming less and more common, respectively. These new avenues of stakeholder communication are allowing the National Park Service to devise research plans to prepare for environmental change, guide resource allocation, and support decision-making in a clear and timely manner.
Urinary Tract Infection in Febrile Children with Sickle Cell Disease Who Present to the Emergency Room with Fever
Authors: Patel Nehal , Farooqi Ahmad , Callaghan Michael , Sethuraman Usha
Published: May 2020

Sickle cell disease (SCD) patients are thought to be at higher risk for urinary tract infections (UTIs) compared to the general population secondary to increased sickling, abnormal urinary acidification, and an inability to concentrate the urine. The incidence of UTI in febrile children with SCD in the United States is unknown. Our objectives were to determine the rate of UTI among febrile SCD children and describe the risk factors for UTI in this population. We conducted a retrospective chart review of all febrile SCD patients <4 years of age who presented to a pediatric emergency department from 2012–2017 and who had a sterile sample of urine for analysis. A total of 167 febrile patients with SCD with 464 visits were identified. The majority were African American (95.2%), female (58.7%), and had hemoglobin SS (HbSS) (65.3%). The rate of UTI was 4.1%. All patients with a UTI were African American females with a median age of 19 months (IQR 12–30). On regression analysis, no risk factors were associated with a UTI. We found the rate of UTI in febrile young children with SCD was comparable to non-SCD children. Larger studies are required to identify the presence of risk factors for UTI in this population.
Academia Europaea Position Paper on Translational Medicine: The Cycle Model for Translating Scientific Results into Community Benefits
Authors: Hegyi Péter , Petersen Ole H. , Holgate Stephen , Erőss Bálint , Garami András , Szakács Zsolt , Dobszai Dalma , Balaskó Márta , Kemény Lajos , Peng Shuang , Monteiro Joao , Varró András , Lamont Tara , Laurence Jeffrey , Gray Zoe , Pickles Andrew , FitzGerald Garret A. , Griffiths Christopher E.M. , Jassem Jacek , Rusakov Dmitri A. , Verkhratsky Alexei , Szentesi Andrea
Published: May 2020

Introduction: Translational science has gained prominence in medicine, but there is still much work to be done before scientific results are used optimally and incorporated into everyday health practice. As the main focus is still on generating new scientific data with financial resources primarily available for that purpose, other activities that are necessary in the transition from research to community benefit are considered less needy. The European Statistical Office of the European Commission has recently reported that 1.7 million people under 75 years of age died in Europe in 2016, with around 1.2 million of those deaths being avoidable through effective primary prevention and public health intervention. Therefore, Academia Europaea, one of the five Pan-European networks that form SAPEA (Science Advice for Policy by European Academies), a key element of the European Commission’s Scientific Advice Mechanism (SAM), has launched a project to develop a model to facilitate and accelerate the utilisation of scientific knowledge for public and community benefit. Methods: During the process, leaders in the field, including prominent basic and clinical researchers, editors-in-chief of high-impact journals publishing translational research articles, translational medicine (TM) centre leaders, media representatives, academics and university leaders, developed the TM cycle, a new model that we believe could significantly advance the development of TM. Results: This model focuses equally on the acquisition of new scientific results healthcare, understandable and digestible summation of results, and their communication to all participants. We have also renewed the definition in TM, identified challenges and recommended solutions. Conclusion: The authors, including senior officers of Academia Europaea, produced this document to serve as a basis for revising thinking on TM with the end result of enabling more efficient and cost-effective healthcare.
Tetralogy of Fallot or Pulmonary Atresia with Ventricular Septal Defect after the Age of 40 Years: A Single Center Study
Authors: Hock Julia , Schwall Laurent , Pujol Claudia , Hager Alfred , Oberhoffer Renate , Ewert Peter , Tutarel Oktay
Published: May 2020

Background: The population of adults with tetralogy of Fallot (TOF) or pulmonary atresia with ventricular septal defect (PA/VSD) is growing and aging. Data regarding older patients are scarce. Prognostic outcome parameters in adults with TOF or PA/VSD ≥ 40 years were studied. Methods: This was a retrospective study of patients ≥ 40 years of age during the study period (January 2005–March 2018). Major adverse cardiac events (MACE) were a combined primary endpoint including death from any cause, prevented sudden cardiac death, pacemaker implantation, arrhythmia, and new-onset heart failure. Additionally, MACE II (secondary endpoint) was a combination of death from any cause and prevented sudden cardiac death. Results: 184 (58.7% female, mean age 45.3 ± 7.2 years) patients were included (159 (86.4%) TOF and 25 (13.6%) PA/VSD). During a median follow-up of 3.1 years (IQR: 0.6–6.5), MACE occurred in 35 and MACE II in 13 patients. On multivariable analysis, New York Heart Association class [HR: 2.1, 95% CI: 1.2–3.6, p = 0.009] emerged as an independent predictor for MACE, and age at corrective surgery [HR: 13.2, 95% CI: 1.6–107.1, p = 0.016] for MACE II. Conclusions: Adults with TOF or PA/VSD ≥ 40 years are burdened with significant morbidity and mortality. New York Heart Association class and age at corrective surgery were independent predictors of outcome.
Outcomes of an Accelerated Inpatient Refeeding Protocol in 103 Extremely Underweight Adults with Anorexia Nervosa at a Specialized Clinic in Prien, Germany
Authors: Koerner Thorsten , Haas Verena , Heese Julia , Karacic Matislava , Ngo Elmar , Correll Christoph U. , Voderholzer Ulrich , Cuntz Ulrich
Published: May 2020

Background: In mildly to moderately malnourished adolescent patients with anorexia nervosa (AN), accelerated refeeding protocols using higher initial calory supply coupled with phosphate supplements were not associated with a higher incidence of refeeding syndrome (RS). It is unclear whether this is also a feasible approach for extremely malnourished, adult AN patients. Methods: Outcomes of a clinical refeeding protocol involving a targeted initial intake of ≥2000 kcal/day, routine supplementation of phosphate and thiamine as well as close medical monitoring, were evaluated. A retrospective chart review including AN patients with a body mass index (BMI) <13 kg/m² was conducted, to describe changes in weight, BMI, and laboratory parameters (phosphate, creatine kinase, hematocrit, sodium, liver enzymes, and blood count) over four weeks. Results: In 103 female patients (age, mean ± standard deviation (SD) = 23.8 ± 5.3 years), BMI between admission and follow-up increased from 11.5 ± 0.9 to 13.1 ± 1.1 kg/m² and total weight gain within the first four weeks was 4.2 ± 2.0 kg (mean, SD). Laboratory parameter monitoring indicated no case of RS, but continuous normalization of blood parameters. Conclusions: Combined with close medical monitoring and electrolyte supplementation, accelerated refeeding may also be applied to achieve medical stabilization in extremely underweight adults with AN without increasing the risk of RS.
Impact of Midurethral Sling Implantation on Sexual Function in Women with Stress Urinary Incontinence
Authors: Horosz Edyta , Zwierzchowska Aneta , Pomian Andrzej , Majkusiak Wojciech , Tomasik Paweł , Barcz Ewa
Published: May 2020

Stress urinary incontinence (SUI) negatively influences sexual functions. However, the available data on sexual activity of patients who underwent midurethral sling (MUS) implantation are inconsistent. Our aim was to evaluate the impact of MUS implantation on sexual functions of women with SUI. We enrolled 171 patients undergoing the MUS procedure. Preoperative examination included the cough test, 1 h pad test and the Prolapse/Urinary Incontinence Sexual Questionnaire, IUGA Revised (PISQ-IR). All patients had the retropubic sling implanted. Follow-up visits were performed 6–12 months after surgery. Objective cure rate was obtained in 90.98% of patients. Coital incontinence was reported by 56% of women before the surgery, and 8.6% afterwards. Among women who gained continence, significant improvement in sexual function was observed in the majority of the domains. In women who were not objectively cured (9.02%), we did not observe improvement in sexual life. All these patients indicated fear of leaking urine during sexual activity as the main cause of avoiding sex, similarly as before operation. To conclude, successful treatment of SUI with MUS significantly improves the quality of sexual life. On the other hand, persistent incontinence appears to be the most probable cause of lack of improvement in the quality of sexual life.
Specific EEG Encephalopathy Pattern in SARS-CoV-2 Patients
Authors: Pastor Jesús , Vega-Zelaya Lorena , Martín Abad Elena
Published: May 2020

We used quantified electroencephalography (qEEG) to define the features of encephalopathy in patients released from the intensive care unit after severe illness from COVID-19. Artifact-free 120–300 s epoch lengths were visually identified and divided into 1 s windows with 10% overlap. Differential channels were grouped by frontal, parieto-occipital, and temporal lobes. For every channel and window, the power spectrum was calculated and used to compute the area for delta (0–4 Hz), theta (4–8 Hz), alpha (8–13 Hz), and beta (13–30 Hz) bands. Furthermore, Shannon’s spectral entropy (SSE) and synchronization by Pearson’s correlation coefficient (ρ) were computed; cases of patients diagnosed with either infectious toxic encephalopathy (ENC) or post-cardiorespiratory arrest (CRA) encephalopathy were used for comparison. Visual inspection of EEGs of COVID patients showed a near-physiological pattern with scarce anomalies. The distribution of EEG bands was different for the three groups, with COVID midway between distributions of ENC and CRA; specifically, temporal lobes showed different distribution for EEG bands in COVID patients. Besides, SSE was higher and hemispheric connectivity lower for COVID. We objectively identified some numerical EEG features in severely ill COVID patients that can allow positive diagnosis of this encephalopathy.
Agreement between Type 2 Diabetes Risk Scales in a Caucasian Population: A Systematic Review and Report
Authors: Ayensa-Vazquez Jose Angel , Leiva Alfonso , Tauler Pedro , López-González Angel Arturo , Aguiló Antoni , Tomás-Salvá Matías , Bennasar-Veny Miquel
Published: May 2020

Early detection of people with undiagnosed type 2 diabetes (T2D) is an important public health concern. Several predictive equations for T2D have been proposed but most of them have not been externally validated and their performance could be compromised when clinical data is used. Clinical practice guidelines increasingly incorporate T2D risk prediction models as they support clinical decision making. The aims of this study were to systematically review prediction scores for T2D and to analyze the agreement between these risk scores in a large cross-sectional study of white western European workers. A systematic review of the PubMed, CINAHL, and EMBASE databases and a cross-sectional study in 59,042 Spanish workers was performed. Agreement between scores classifying participants as high risk was evaluated using the kappa statistic. The systematic review of 26 predictive models highlights a great heterogeneity in the risk predictors; there is a poor level of reporting, and most of them have not been externally validated. Regarding the agreement between risk scores, the DETECT-2 risk score scale classified 14.1% of subjects as high-risk, FINDRISC score 20.8%, Cambridge score 19.8%, the AUSDRISK score 26.4%, the EGAD study 30.3%, the Hisayama study 30.9%, the ARIC score 6.3%, and the ITD score 3.1%. The lowest agreement was observed between the ITD and the NUDS study derived score (κ = 0.067). Differences in diabetes incidence, prevalence, and weight of risk factors seem to account for the agreement differences between scores. A better agreement between the multi-ethnic derivate score (DETECT-2) and European derivate scores was observed. Risk models should be designed using more easily identifiable and reproducible health data in clinical practice.
An Efficient COVID-19 Prediction Model Validated with the Cases of China, Italy and Spain: Total or Partial Lockdowns?
Authors: Sanchez-Caballero Samuel , Selles Miguel A. , Peydro Miguel A. , Perez-Bernabeu Elena
Published: May 2020

The present work develops an accurate prediction model of the COVID-19 pandemic, capable not only of fitting data with a high regression coefficient but also to predict the overall infections and the infection peak day as well. The model is based on the Verhulst equation, which has been used to fit the data of the COVID-19 spread in China, Italy, and Spain. This model has been used to predict both the infection peak day, and the total infected people in Italy and Spain. With this prediction model, the overall infections, the infection peak, and date can accurately be predicted one week before they occur. According to the study, the infection peak took place on 23 March in Italy, and on 29 March in Spain. Moreover, the influence of the total and partial lockdowns has been studied, without finding any meaningful difference in the disease spread. However, the infected population, and the rate of new infections at the start of the lockdown, seem to play an important role in the infection spread. The developed model is not only an important tool to predict the disease spread, but also gives some significant clues about the main factors that affect to the COVID-19 spread, and quantifies the effects of partial and total lockdowns as well.
Effects of Pulp Fiber and Epoxidized Tung Oil Content on the Properties of Biocomposites Based on Polylactic Acid
Authors: Nguyen Van Khoi , Nguyen Thanh Tung , Pham Thi Thu Ha , Pham Thu Trang
Published: May 2020

Recently, various environmental-friendly materials have been investigated and developed, especially composites of polylactic acid (PLA) and plant fibers. This paper investigates the effects of pulp fiber (PF) and epoxidized Tung oil (ETO) content on the properties of biocomposites, based on polylactic acid. The bleached pulp fiber reinforced PLA (PLA/PF) composites with 10–50 wt% fiber contents and 0–15% epoxidized Tung oil contents (with a certain number of fiber) were prepared in an internal mixer (Plastograph® EC) at 150 °C. The mechanical properties of PLA/PF composites were improved significantly. The pulp fiber reinforced PLA composites, with the fiber content of 30 wt%, were found to have the highest mechanical properties. The tensile and flexural properties of PLA/Tung oil-soaked-pulp fiber composites were higher than those of PLA/Tung oil unsoaked pulp fiber composites. In addition, the degradation temperature of PLA-based composites decreased after adding more pulp fiber. The pulp fibers were well-dispersed in the PLA matrix with the content up to 30 wt%. The interaction between pulp fiber and PLA matrix improved by the addition of epoxidized Tung oil. Epoxidized Tung oil also improved tensile and flexural strength of composite materials when it was added with a number of below 10% of fiber.
Finite Element Modeling of the Fiber-Matrix Interface in Polymer Composites
Authors: Singh Daljeet K. , Vaidya Amol , Thomas Vinoy , Theodore Merlin , Kore Surbhi , Vaidya Uday
Published: May 2020

Polymer composites are used in numerous industries due to their high specific strength and high specific stiffness. Composites have markedly different properties than both the reinforcement and the matrix. Of the several factors that govern the final properties of the composite, the interface is an important factor that influences the stress transfer between the fiber and matrix. The present study is an effort to characterize and model the fiber-matrix interface in polymer matrix composites. Finite element models were developed to study the interfacial behavior during pull-out of a single fiber in continuous fiber-reinforced polymer composites. A three-dimensional (3D) unit-cell cohesive damage model (CDM) for the fiber/matrix interface debonding was employed to investigate the effect of interface/sizing coverage on the fiber. Furthermore, a two-dimensional (2D) axisymmetric model was used to (a) analyze the sensitivity of interface stiffness, interface strength, friction coefficient, and fiber length via a parametric study; and (b) study the shear stress distribution across the fiber-interface-matrix zone. It was determined that the force required to debond a single fiber from the matrix is three times higher if there is adequate distribution of the sizing on the fiber. The parametric study indicated that cohesive strength was the most influential factor in debonding. Moreover, the stress distribution model showed the debonding mechanism of the interface. It was observed that the interface debonded first from the matrix and remained in contact with the fiber even when the fiber was completely pulled out.
Determination and Quantification of the Distribution of CN-NL Nanoparticles Encapsulating Glycyrrhetic Acid on Novel Textile Surfaces with Hyperspectral Imaging
Authors: A. Obisesan Kudirat , Neri Simona , Bugnicourt Elodie , Campos Inmaculada , Rodriguez-Turienzo Laura
Published: May 2020

Chitin Lignin nanoparticles (CN-NL), standalone and encapsulating glycyrrhetic acid (GA), were applied on novel substrates for textiles to obtain antibacterial, antioxidant properties. Their homogeneous application is an important parameter that can strongly influence the final performance of the investigated textiles for its cosmetic and medical use. In this paper, hyperspectral imaging techniques combined with chemometric tools were investigated to study the distribution and quantification of CN-NL/GA on chitosan and CN-NL on pullulan substrates. To do so, samples of chitosan and pullulan impregnated with CN-NL/GA and CN-NL were analysed through Short Wave Infrared (SWIR) and Visible-Near Infrared (VisNIR) hyperspectral cameras. Two different chemometric tools for qualitative and quantitative analysis have been applied, principal component analysis (PCA) and partial least square regression (PLSR) models. Promising results were obtained in the VisNIR range, which made it possible for us to visualize the CN-NL/GA compound on chitosan and CN-NL on pullulan substrates. Additionally, the PLSR model results had determination coefficient ( R C 2 ) for calibration and cross-validation ( R C V 2 )   values of 0.983 and 0.857, respectively. Minimum values of root-mean-square error for calibration (RMSEC) and cross-validation (RMSECV) of CN-NL/GA were 0.333 and 0.993 g, respectively. The results demonstrate that hyperspectral imaging combined with chemometrics offers a powerful tool for studying the distribution on chitosan and pullulan substrates and to quantify the content of CN-NL/GA compounds on chitosan substrates.
Characterisation of Laser System Power Draws in Materials Processing
Authors: Goffin Nicholas , Jones Lewis C. R. , Tyrer John , Ouyang Jinglei , Mativenga Paul , Woolley Elliot
Published: May 2020

Due to their high speed and versatility, laser processing systems are now commonplace in many industrial production lines. However, as the need to reduce the environmental impact from the manufacturing industry becomes more urgent, there is the opportunity to evaluate laser processing systems to identify opportunities to improve energy efficiencies and thus reduce their carbon footprint. While other researchers have studied laser processing, the majority of previous work on laser systems has focused on the beam–material interaction, overlooking the whole system viewpoint and the significance of support equipment. In this work, a methodical approach is taken to design a set of energy modelling terminologies and develop a structured power metering system for laser systems. A 300 W fibre laser welding system is used to demonstrate the application of the power characterization system by utilizing a purpose-built power meter. The laser is broken down according to sub-system, with each part analysed separately to give a complete overall power analysis, including all auxiliary units. The results show that the greatest opportunities for efficiency improvements lie in the auxiliary units that support the laser devices as these were responsible for a majority of the electrical draw; 63.1% when the laser was operated at 240 W, and increasing as the beam power reduced. The remaining power draw was largely apportioned to electrical supply inefficiencies. In this work, the laser device delivered a maximum of 6% of the total system power. The implications of these results on laser processing system design are then discussed as is the suitability of the characterization process for use by industry on a range of specific laser processing systems.
Free-Surface Effects on the Performance of Flapping-Foil Thruster for Augmenting Ship Propulsion in Waves
Authors: Filippas Evangelos S. , Papadakis George P. , Belibassakis Kostas A.
Published: May 2020

Flapping foils located beneath or to the side of the hull of the ship can be used as unsteady thrusters, augmenting ship propulsion in waves. The basic setup is composed of a horizontal wing, which undergoes an induced vertical motion due to the ship’s responses in waves, while the self-pitching motion of the wing is controlled. Flapping foil thrusters can achieve high level of thrust as indicated by measurements and numerical simulations. Due to the relatively small submergence of the above biomimetic ship thrusters, the free-surface effects become significant. In the present work, the effect of the free surface on the performance of flapping foil thruster is assessed by means of two in-house developed computational models. On one hand, a cost-effective time-domain boundary element method (BEM) solver exploiting parallel programming techniques and general purpose programming on graphics processing units (GPGPU) is employed, while on the other hand a higher fidelity RANSE finite volume solver implemented for high performance computing (HPC) is used, and comparative results are presented. BEM and RANSE calculations present quite similar trends with respect to mean submergence depth, presenting 12%, 28%, and 18% of differences concerning the mean values of lift, thrust, and moment coefficients, respectively. The latter differences become very small after enhancement of the BEM model to include viscous corrections. Useful information and data are derived supporting the design of the considered biomimetic thrusters, for moderate submergence depths and conditions characterized by minor flow separation effects.
Security Measures as a Factor in the Competitiveness of Accommodation Facilities
Authors: Nagaj Rafał , Žuromskaitė Brigita
Published: May 2020

The main aim of this article was to assess whether the level of competitiveness of accommodation facilities results from the level of safety and security provided to consumers of these services, measured by the number of security measures applied in them. The authors’ task was to examine the level of concentration of security measures in the accommodation facilities and to assess whether the quality of services measured by the star-rating system provided a higher level of safety and security for customers of the accommodation facilities, measured by the number of security measures applied in them. It was decided to examine whether the level of concentration of security measures at the accommodation facilities was treated by these entities as a factor of their competitiveness. Two locations in Central and Eastern Europe, one in Poland and one in Lithuania, were analyzed. The article calculated the frequency of these measures at the accommodation facilities by type of facility (according to the star-rating system) and type of security measure (as a weighted average) and their concentration using the Herfindahl–Hirscham Index. The results showed that the higher the quality of services provided (more stars), the higher the level of safety and security is ensured. It was also found that a higher level of security was not reflected in the prices of accommodation services.
Mapping Suburbs Based on Spatial Interactions and Effect Analysis on Ecological Landscape Change: A Case Study of Jiangsu Province from 1998 to 2018, Eastern China
Authors: Tian Yasi
Published: May 2020

As the transitional area between urban and rural areas, land-use change in suburbs is drastic, which generates negative effects on the ecological environment. However, the identification of the suburbs remains controversial. Usually, the density of the population and residential land is referenced, and the close spatial interactions between urban areas and suburbs are generally neglected. To fill this research gap, this study adopts a case study method to map the suburbs of Jiangsu based on estimating the spatial interactions. First, a regression model is built to estimate the population distribution. Second, a radiation model is utilized to evaluate the spatial interaction at a grid level. After the main urban area is identified based on the high density of the population and construction land, the interaction strength between the main urban grid and other grid areas is calculated, and the grids that share high values of interaction strength with urban grids are identified as suburban areas. Finally, the suburbs of Jiangsu in 1998 and 2018 are mapped, and the ecological landscape pattern metrics are used to verify the effects of suburban expansion. As a result, the suburban expansion of Jiangsu over the 20 years was significant, and the effects of suburban expansion on ecological land fragmentation were evident. On the basis of the results, the enlightenment of mapping suburbs on ecological landscape planning is discussed.
Spatial Orientation Skill for Landscape Architecture Education and Professional Practice
Authors: Carbonell-Carrera Carlos , Saorin Jose , Hess-Medler Stephany
Published: May 2020

Professional landscape architecture organizations have requested training from educational institutions based on new skills and methodologies in the curriculum development of students. Landscape architects need to visualize and evaluate the spatial relationships between the different components of the landscape using two-dimensional (2D) or three-dimensional (3D) maps and geospatial information, for which spatial orientation skills are necessary. The data from six workshops conducted throughout the 2010–2020 period, in which 560 second-year engineering students participated using different strategies and technical tools for spatial orientation skills’ development, were collected in a unique study. Factors such as the technology used, the gaming environment, the type of task, the 2D/3D environment, and the virtual environment were considered. The Perspective-Taking Spatial Orientation Test was the measurement tool used. The results show that mapping tasks are more efficient than route-based tasks. Strategies using 2D and a 2D/3D combination are more effective than those with only 3D. First-person perspective gaming environments are also a valid alternative. The technologies applied in this study are easy to use and free, and a measurement tool is provided. This facilitates an interdisciplinary approach between landscape architecture education and professional practice since these workshops could also be easily carried out by professional bodies for landscape planning and management.
Statistical RF/Analog Integrated Circuit Design Using Combinatorial Randomness for Hardware Security Applications
Authors: Chen Ethan , Chen Vanessa
Published: May 2020

While integrated circuit technologies keep scaling aggressively, analog, mixed-signal, and radio-frequency (RF) circuits encounter challenges by creating robust designs in advanced complementary metal–oxide–semiconductor (CMOS) processes with the diminishing voltage headroom. The increasing random mismatch of smaller feature sizes in leading-edge technology nodes severely limit the benefits of scaling for (RF)/analog circuits. This paper describes the details of the combinatorial randomness by statistically selecting device elements that relies on the significant growth in subsets number of combinations. The randomness can be utilized to provide post-manufacturing reconfiguration of the selectable circuit elements to achieve required specifications for ultra-low-power systems. The calibration methodology is demonstrated with an ultra-low-voltage chaos-based true random number generator (TRNG) for energy-constrained Internet of things (IoT) devices in the secure communications.
Numerical Range of Moore–Penrose Inverse Matrices
Authors: Chien Mao-Ting
Published: May 2020

Let A be an n-by-n matrix. The numerical range of A is defined as W ( A ) = { x * A x : x ∈ C n , x * x = 1 } . The Moore–Penrose inverse A + of A is the unique matrix satisfying A A + A = A , A + A A + = A + , ( A A + ) * = A A + , and ( A + A ) * = A + A . This paper investigates the numerical range of the Moore–Penrose inverse A + of a matrix A, and examines the relation between the numerical ranges W ( A + ) and W ( A ) .
Astaxanthin Modulates Apoptotic Molecules to Induce Death of SKBR3 Breast Cancer Cells
Authors: Kim Min Sung , Ahn Yong Tae , Lee Chul Won , Kim Hyungwoo , An Won Gun
Published: May 2020

Astaxanthin (AST) is related to apoptosis but the details of the mechanism of how AST makes apoptosis is not clear. The present study investigated apoptotic effects of AST to SKBR3, a breast cancer cell line in detail. Cell viability assay showed cellular proliferation and morphological changes of the cells were observed under AST treatment. FACS analysis indicated that AST blocked cell cycle progression at G0/G1, suppressed proliferation dose-dependently, and induced apoptosis of the cells. The apoptosis of the cells by AST was further demonstrated through the decreased expression level of mutp53 and cleaved a PARP-1 fragment, respectively. In addition, AST induced the intrinsic apoptosis of the cells by activation of Bax/Bcl2, cleaved caspase-3, and cleaved caspase-9 as well as the phosphorylation of ERK1/2, JNK, and p38. Furthermore, AST decreased production of intracellular reactive oxygen species as well as modulated expressions of superoxide dismutases and Pontin, an anti-apoptotic factor. Co-immunoprecipitation assay revealed AST reduced interaction between Pontin and mutant p53. Taken together, these studies proved that AST regulates the expression of apoptotic molecules to induce intrinsic apoptosis of the cells, suggesting AST therapy might provide an alternative for improving the efficacies of other anti-cancer therapies for breast cancer.
Serum Chloride Levels at Hospital Discharge and One-Year Mortality among Hospitalized Patients
Authors: Petnak Tananchai , Thongprayoon Charat , Cheungpasitporn Wisit , Bathini Tarun , Vallabhajosyula Saraschandra , Chewcharat Api , Kashani Kianoush
Published: May 2020

This study aimed to assess the one-year mortality risk based on discharge serum chloride among the hospital survivors. We analyzed a cohort of adult hospital survivors at a tertiary referral hospital from 2011 through 2013. We categorized discharge serum chloride; ≤96, 97–99, 100–102, 103–105, 106–108, and ≥109 mmoL/L. We performed Cox proportional hazard analysis to assess the association of discharge serum chloride with one-year mortality after hospital discharge, using discharge serum chloride of 103–105 mmoL/L as the reference group. Of 56,907 eligible patients, 9%, 14%, 26%, 28%, 16%, and 7% of patients had discharge serum chloride of ≤96, 97–99, 100–102, 103–105, 106–108, and ≥109 mmoL/L, respectively. We observed a U-shaped association of discharge serum chloride with one-year mortality, with nadir mortality associated with discharge serum chloride of 103–105 mmoL/L. When adjusting for potential confounders, including discharge serum sodium, discharge serum bicarbonate, and admission serum chloride, one-year mortality was significantly higher in both discharge serum chloride ≤99 hazard ratio (HR): 1.45 and 1.94 for discharge serum chloride of 97–99 and ≤96 mmoL/L, respectively; p < 0.001) and ≥109 mmoL/L (HR: 1.41; p < 0.001), compared with discharge serum chloride of 103–105 mmoL/L. The mortality risk did not differ when discharge serum chloride ranged from 100 to 108 mmoL/L. Of note, there was a significant interaction between admission and discharge serum chloride on one-year mortality. Serum chloride at hospital discharge in the optimal range of 100–108 mmoL/L predicted the favorable survival outcome. Both hypochloremia and hyperchloremia at discharge were associated with increased risk of one-year mortality, independent of admission serum chloride, discharge serum sodium, and serum bicarbonate.
An Experimental Study of Membrane Contactor Modules for Recovering Cyanide through a Gas Membrane Process
Authors: Quilaqueo Michelle , Seriche Gabriel , Valetto Sicely , Barros Lorena , Díaz-Quezada Simón , Ruby-Figueroa René , Troncoso Elizabeth , Estay Humberto
Published: May 2020

Cyanide is one of the main reagents used in gold mining that can be recovered to reduce operational costs. Gas membrane technology is an attractive method for intensifying both the stripping and absorption processes of valuable compounds, such as cyanide. However, scaling-up this technology from laboratory to industry is an unsolved challenge because it requires the improvement of the experimental methodologies that replicate lab-scale results at a larger scale. With this purpose in mind, this study compares the performance of three different hollow fiber membrane contactor modules (1.7 × 5.5 Mini Module, 1.7 × 10 Mini Module, and 2.5 × 8 Extra Flow). These are used for recovering cyanide from aqueous solutions at laboratory scale, using identical operational conditions. For each experimental set-up, mass-transfer correlations at the ranges of feed flows assayed were determined. The modules with the smallest and largest area of mass transfer reached similar cyanide recoveries (>95% at 60 min), which demonstrate the impact of module configuration on their operating performance. The results obtained here are limited for scaling-up the membrane module performance only because operating modules with the largest area results in a low Re number. This fact limits the extrapolation of results from the mass-transfer correlation.
Inversion of the Sign of the Short-Range Order as a Function of the Composition of Fe–Cr Alloys at Warm Severe Plastic Deformation and Electron Irradiation
Authors: Kozlov Kirill , Shabashov Valery , Zamatovskii Andrey , Novikov Evgenii , Ustyugov Yurii
Published: May 2020

This paper presents the results of a Mössbauer spectroscopy investigation of the processes in the binary alloys Fe100−cCrc (c, at. % = 6.0, 9.4, 13.2) and of the short-range (SR) atomic ordering accelerated by applying warm severe plastic deformation via high pressure torsion (HPT). After warm HPT treatment, in the vicinity of the concentration c = 9 at. %, there was revealed to be an inversion of the sign of the SR order, the anomaly of the formation of a Fe–Cr solid solution, which was predicted ab initio and is observed at long-term anneals and exposures to irradiation by electrons. The acceleration of the SR ordering at HPT is due to the continuous generation and a large number density of mobile point defects.
On the Influence of the Tool Path and Intrusion Depth on the Geometrical Accuracy in Incremental Sheet Forming
Authors: Schmitz Roman Ulrich Christopher , Bremen Thomas , Bailly David Benjamin , Hirt Gerhard Kurt Peter
Published: May 2020

Incremental sheet forming (ISF) is a flexible sheet metal forming process to realize products within short time from design to the first produced part. Although fundamental research on ISF has been carried out around the world, ISF still misses commonly required tolerances for industrial application. In this study, the influences of tool path as well as intrusion depth of the forming tool into the sheet material on the geometrical accuracy were investigated. In the conducted experiments, both flat and stretch-formed sheet metal blanks with different tool paths and intrusion depths were examined. Experimental and numerical investigations showed that changes in the range of a tenth millimeter of the intrusion depth with a consistent tool path lead to different resulting part geometries. A better understanding of the sensitive influence of the tool path and the intrusion depth on the resulting geometry might lead to more accurate parts in the future.
Effects of Arc Length Adjustment on Weld Bead Formation and Droplet Transfer in Pulsed GMAW Based on Datum Current Time
Authors: Zhai Peizhuo , Xue Songbai , Wang Jianhao , Chen Weizhong , Chen Tao , Ji Shilei
Published: May 2020

The characteristics of weld bead formation and droplet transfer in pulsed gas metal arc weld (GMAW) with different arc lengths were studied by changing the base current time in this work. The results showed that it was easier to cause short circuits and spatters with a short arc. However, the deviation between the deepest point of penetration and the center of bead will be aggravated with the increase of arc length. In addition, more than 90% “one drop per pulse” (ODPP) transfer mode can be obtained when the pulse parameters were selected properly. However, the short arc trended to rise the proportion of “multiple drops per pulse” (MDPP), and the long arc trended towards increasing the proportion of “one drop per multiple pulses” (ODMP). Additionally, with the growth of the arc in the projected transfer zone, the penetration tended to become shallower because of the increase of arc heat dissipation, the fall of arc energy density, and droplet impact force. Overall, the strategy of choosing suitable arc length of pulsed GMAW was summarized: in order to obtain high-quality bead formation and weld joints, a shorter arc in the projected transfer zone was recommended.
Theoretical Model of Residual Stress and Warpage for Wire and Arc Additive Manufacturing Stiffened Panels
Authors: Geng Haibin , Li Jinglong , Gao Jianjun , Lin Xin
Published: May 2020

Wire and arc additive manufacturing of stiffened ribs for fabricating large integral panel components holds promise for lightweight construction, but stress and warpage remain intractable problems. This work take stress in central lines as a research focus, theoretically analyzes stress evolution along central lines without a stress distribution hypothesis, then further develops prediction models of warpage, based on general beam theory. The stress and warpage models are then verified by experimental results. The results showed that below 40 layers, the stress in the top layer increased rapidly to the yield strength. Following the continuous deposition of up to 100 layers, stress increased slowly, then gradually trended to a constant level. After 100 layers of deposition, the top-layer-plane stress in the 10th layer decreased from 68 MPa to 5 MPa, and the plane stress in the 90th layer decreased from 296 MPa to 245 MPa. Post-heating treatment effect was important for temperature uniformity. The largest warpage (3.48 mm) happened when stiffener was designed as 30 layers.
Micromachining of High Quality PMN–31%PT Single Crystals for High-Frequency (>20 MHz) Ultrasonic Array Transducer Applications
Authors: Lei Zhihong , Chen Yan , Xu Guisheng , Liu Jinfeng , Yuan Maodan , Zeng Lvming , Ji Xuanrong , Wu Dawei
Published: May 2020

A decrease of piezoelectric properties in the fabrication of ultra-small Pb(Mg1/3Nb2/3)–x%PbTiO3 (PMN–x%PT) for high-frequency (>20 MHz) ultrasonic array transducers remains an urgent problem. Here, PMN–31%PT with micron-sized kerfs and high piezoelectric performance was micromachined using a 355 nm laser. We studied the kerf profile as a function of laser parameters, revealing that micron-sized kerfs with designated profiles and fewer micro-cracks can be obtained by optimizing the laser parameters. The domain morphology of micromachined PMN–31%PT was thoroughly analyzed to validate the superior piezoelectric performance maintained near the kerfs. A high piezoresponse of the samples after micromachining was also successfully demonstrated by determining the effective piezoelectric coefficient (d33*~1200 pm/V). Our results are promising for fabricating superior PMN–31%PT and other piezoelectric high-frequency (>20 MHz) ultrasonic array transducers.