bluuebunny/crossref_metadata_2025 huggingface dataset:
Análisis cuantitativo del ordenamiento de alúmina anódica nanoporosa obtenida a diferentes potenciales de anodizado
Authors: Aguilar-Sierra Sara María , Echeverría Félix
Published: August 2021

Contexto: La alúmina anódica nanoporosa es un material de gran interés debido a su baja densidad, alta relación de aspecto y a que es posible obtener estructuras altamente ordenadas de ella. En las últimas décadas, los investigadores han concentrado sus esfuerzos en controlar las características morfológicas de los arreglos de poros fabricados, particularmente su ordenamiento. Recientemente, se empezó a migrar la caracterización del ordenamiento de las estructuras de cualitativa a cuantitativa, conllevando esto al desarrollo de herramientas de caracterización más precisas.
Método: En este trabajo se evaluó el efecto del potencial de anodizado en el ordenamiento de alúmina anódica nanoporosa (AAN) fabricada en ácido oxálico al 0,3 M. Se empleó la transformada rápida de Fourier (TRF) como herramienta para cuantificar el ordenamiento de la AAN fabricada. Los valores del grado de ordenamiento se obtuvieron mediante el cálculo del radio de regularidad basado en las imágenes obtenidas de las TRF generadas a partir de las imágenes superficiales de microscopía electrónica de barrido (MEB) de las muestras de AAN.
Resultados: Se observó que a medida que el potencial de anodizado aumenta, el radio de regularidad disminuye para los potenciales evaluados. Adicionalmente, se evidenció que el diámetro de poro y la distancia entre poros aumentan con el potencial de anodizado.
Conclusiones: Estructuras altamente ordenadas pueden ser obtenidas mediante el anodizado de aluminio puro en ácido oxálico al 0,3 M a 40 V, 50 V y 55 V. El cálculo del radio de regularidad representa un valioso instrumento para la caracterización cuantitativa del ordenamiento de las estructuras de AAN. La determinación del grado de ordenamiento de la AAN se relaciona con sus propiedades y por lo tanto con su aplicación. La comprensión del efecto del potencial de anodizado en el ordenamiento de los poros de alúmina proporciona herramientas para mejorar el diseño de dispositivos basados en la AAN.
 
Agradecimientos: Los autores agradecen a la Universidad Cat´olica Luis Amig´o por la financiaci´on del proyecto n´umero: 57156 y a Colciencias y la Universidad de Antioquia, con el n´umero de contrato: 0636-2013.
Diseño de un controlador lineal cuadrático gaussiano y un controlador autosintonizado por asignación de polos para el control del voltaje de un generador CD
Authors: Garcia Jaimes Luis Edo , Piedrahita Flórez David
Published: August 2021

Contexto: En este artículo se presenta el diseño de un controlador lineal cuadrático gaussiano para regular el voltaje de un generador CD y se compara su desempeño con el de un regulador autoajustable sintonizado por asignación de polos.
Método: Para implementar estas estrategias de control, se utiliza el prototipo de un generador CD y se obtiene el modelo matemático del sistema utilizando identificación no paramétrica, se presentan las bases teóricas y el diseño de las dos estrategias de control y se realiza la comparación del desempeño de los dos controladores utilizando métricas de la integral del error y respuesta temporal.
Resultados: Las métricas de la integral del error y las de respuesta temporal muestran que, aunque el desempeño del controlador lineal cuadrático gaussiano es ligeramente superior al presentado por el controlador autoajustable por asignación de polos, con las dos estrategias de control las respuestas del sistema son estables, con buena velocidad de respuesta y error de estado estable igual a cero.
Conclusiones: Las estrategias de control lineal cuadrático gaussiano y el control autosintonizado son una buena alternativa al control convencional y generan un adecuado control del proceso, acorde con los requerimientos del sistema.
Renovando mucho m´as que la confianza
Authors: Diaz Nelson Leonardo
Published: August 2021

Nota editorial Vol. 26 No.1
IMPLEMENTATION OF TOTAL QUALITY MANAGEMENT: THE EFFECT ON PATIENT SAFETY CULTURE, SERVICE QUALITY, AND ITS IMPACT ON PATIENT SATISFACTION AND PRIVATE HOSPITAL PERFORMANCE IN MANADO CITY
Authors: Pondaag Jessy Jousina , Kindangen Paulus , Tawas Hendra N. , Sumarauw Jacky Sigfried Beatrix
Published: August 2021

The purpose of this research is to determine the effect of implementation of Total Quality Management (TQM) on patient safety culture, service quality, patient satisfaction, and hospital performance. This research conducted in private hospitals in Manado City which are: GMIM Pancaran Kasih Hospital, Advent Hospital, Sitti Maryam Hospital, and Siloam Hospital. The research approach used in this research is quantitative approach.

The population in this research is the inpatients. Data collection technique conducted by questionnaires, documentation and observation. The sampling technique used in this research is saturated sampling (census). Data analysis conducted by using path analysis with the using SPSS ver. 25.

The result of this research shows that the implementation of Total Quality Management impacted positively significantly on patient safety culture, the implementation of Total Quality Management impacted positively significantly on hospital service quality, the implementation of Total Quality Management impacted insignificantly on patient satisfaction, the implementation of Total Quality Management impacted positively significantly on hospital performance, Patient Safety Culture impacted positively significantly on patient satisfaction, Patient Safety Culture impacted positively significantly on hospital performance, Service Quality impacted positively significantly on hospital performance, Hospital Performance impacted positively significantly on hospital performance, and Patient Satisfaction impacted positively significantly on hospital performance.
Why children’s news matters: The case of CBBC Newsround in the UK
Authors: Carter Cynthia , Steemers Jeanette , Davies Máire Messenger
Published: August 2021

There has never been a greater need for reliable, truthful news to help citizens navigate and assess the veracity of what they are reading and viewing, especially on social media. Widespread concerns around ‘fake’ news demonstrate an enduring requirement for curated and trustworthy children’s news that addresses children as young citizens with certain rights. Drawing on recent UK events, we discuss the case for children’s news provision by public service broadcasting (PSB) from a communication rights perspective by analyzing the BBC’s 2019 plans to reduce the broadcast presence and originated hours of its flagship news service, Newsround, in favor of online distribution.
Serum adiponectin, body adiposity and metabolic parameters in obese Egyptian children with Down syndrome
Authors: Yahia Sohier , El-Farahaty Reham , EL-Gilany Abdel-Hady , Shoaib Rasha , Ramadan Rowayda , Salem Nanees
Published: August 2021

Objectives

Children with Down syndrome (DS) have a higher risk for obesity. Adiponectin plays a crucial role in obesity-related cardiometabolic comorbidities. The study aimed to explore whether body adiposity indicators, the frequency of metabolic syndrome (MetS) and its components, serum adiponectin and insulin resistance indices as well as the validity of serum adiponectin as a biomarker for MetS are different in prepubertal obese-DS children compared to matched obese-controls.

Methods

Cross-sectional study included 150 prepubertal children classfied into three groups; obese-DS (n=50), obese-control (n=50) and normal-weight-control (n=50). Participants were evaluated for waist-circumference (WC), body adiposity, serum triglycerides, HDL-C, adiponectin and Homeostasis-Model-Assessment of Insulin-Resistance (HOMA-IR). MetS was defined using modified Adult Treatment Panel III-criteria.

Results

Obese-DS had significantly higher WC, %body fat, total-fat mass, trunk-fat mass, trunk/appendicular-fat mass ratio, triglycerides, insulin and HOMA-IR and significantly lower HDL-C values compared to obese-control. Higher prevalence of MetS and its components were observed in obese-DS that was evident at younger age. Adiponectin was significantly lower in obese-DS compared with obese-control and in obese-DS children with MetS compared to obesecontrol with MetS. The decrease in adiponectin with increasing grades of obesity was pronounced in obese-DS. Adiponectin exhibited strong correlations with body adiposity, several MetS components and HOMA-IR in obese-DS. Adiponectin performed better as a biomarker for MetS among obese-DS (AUC=0.808) than obese-control (AUC=0.674).

Conclusions

Prepubertal obese-DS displayed excess body adiposity with pronounced central fat distribution, atherogenic lipid profile and higher insulin resistance compared to matched obese-control. Adiponectin performed better as potential biomarker of MetS in obese-DS than obese-control.
Malabou’s Political Critique of Speculative Realism
Authors: Harman Graham
Published: August 2021

A recent political critique of Speculative Realism by Catherine Malabou finds fault with this loosely arranged movement for its focus on reality in its own right, apart from the subject. Malabou responds with a radical ontological claim, holding effectively – if not always explicitly – that subject and object mutually generate one another amidst a primal void. After criticizing this idea, I point to some of the difficult political consequences of such a position, though Malabou defines it positively as an anarchic awakening that generates new collectivities unconstrained by any thing-in-itself. By contrast, I contend that nonhuman constraints and collaborators are an intimate part of the human political sphere. More generally, it is shown that there are consequences for which sorts of relations are taken to be the primary political relations.
Market Structure and Bank Conduct in the MENA Region
Authors: Awdeh Ali , El Moussawi Chawki , Hamadi Hassan
Published: August 2021

The Middle East North Africa (MENA) region is witnessing a wave of bank consolidations, with many mega-mergers taking place in the Gulf Cooperation Council (GCC) countries. These will result in creating large banks, reducing the number of market players and increasing market concentration; which is already high. A further increase in concentration may raise concerns about the resulting dominance of large banks and the consequences on their pricing behaviour. The interrelationships between market structure and pricing behaviour is summarised by the popular model of industrial economics called the structure–conduct–performance (SCP) model. Consequently, we test the prevalence of this model in a sample of 15 MENA banking sectors to detect the possible existence of an impact running particularly from the structure of banking markets to the pricing behaviour (power) of banks in order to predict a possible emergence of oligopolistic behaviour following bank consolidations. Using a two-stage least squares model, we found a positive and significant impact of market concentration on bank pricing, suggesting that an further increase in MENA banking markets’ concentration may boost banks pricing power and persuade them to increase their returns at the expense of their customers.
A phonological reanalysis of morphological segment deletion and de-affrication in Ik
Authors: Ulfsbjorninn Shanti
Published: August 2021

Ik presents a widespread pattern of allomorphy characterised by morpheme-specific segment-zero alternations (deletions) and de-affrication. Part of the process is clearly phonological because it applies to every item in the language. Final vowels are devoiced into oblivion, though they are always recoverable in Non-Domain-Final context. Case allomorphy shows various item-specific patterns, some affixes overwrite the final-vowels of roots, others do not, and others yet exhibit consonant-zero alternations. Meanwhile, interestingly, there is (ostensibly) morphologically-sensitive consonant deletion that is fully complementary with what is clearly phonological vowel deletion. In fact, an entirely phonological analysis is possible if the consonant-zero alternations are modelled by floating consonants belonging to the exponents of certain morphemes. Therefore, the item/morpheme-specific aspect of the process is actually specific to the exponent of that morpheme. This locates the whole analysis in the phonology and provides a straightforward account of the complementarity of the two deletion processes. The formal analysis is very close to what has been proposed for French, with its floating consonants and its irregular hiatus-driven vowel deletion. The analysis will then be extended to the item-specific idiosyncratic process of de-affrication that is blocked, not by coincidence, precisely in morphologically overwriting environments. In the end, all the phenomena can be accounted for in a modular analysis, provided one gets the representations right.
The Acute Effects From the Use of Weighted Implements on Skill Enhancement in Sport: A Systematic Review
Authors: Jermyn Sam , O'Neill Cian , Coughlan Edward K.
Published: August 2021

Jermyn, S, Neill, CO, and Coughlan, EK. The acute effects from the use of weighted implements on skill enhancement in sport: A systematic review. J Strength Cond Res 35(10): 2922–2935, 2021—Weighted implements are used before competitive performance with the aim of enhancing motor skill execution on return to the standard implement. The purpose of this review was to analyze the existing literature pertaining to the acute effects of weighted implements on respective sporting performance. Following a systematic screening process, 25 studies were identified. This review highlighted the effects of (a) weighted balls and bats on throwing and batting performance and (b) indoor weight throw implements on indoor weight throw performance. Studies reported conflicting effects on immediate performance post–warm-up with the respective implements. Notably, although overweighted bats and overweight attachments are a prominent preparatory tool in baseball, this review found consistent and repeated evidence of degraded batting performance in striking-based studies. Decreased bat velocity, altered swing patterns, subjective-objective mismatches of bat speed and weight, temporal accuracy errors, and inadequate recalibration to the standard bat were identified as acute effects. This review identified an obvious dearth of research into the acute effects of weighted implements on motor skills in other sports with equally complex perceptual motor patterns, such as football (soccer), golf, rugby, basketball, and American football. Future weighted implement research should investigate the acute effects of respective implements on motor skill performance in other sports, such as those aforementioned, with the purpose of exploring relevant implications for preparatory strategies and immediate performance on return to the standard implement.
Automatic Observation of Astronomical Coordinates Using the Shandong University of Science and Technology/National Astronomical Observatories Digital Zenith Tube
Authors: Yuan Jiajia , Guo Jinyun , Shen Yi , Dai Jie , Liu Xin , Kong Qiaoli
Published: August 2021

The digital zenith tube (DZT) is developed based on the astrogeodetic and photogrammetric theory. One prototype of DZT integrating techniques of global positioning system (GPS) and charge-coupled device (CCD) photogrammetry has been developed jointly by Shandong University of Science and Technology and National Astronomical Observatories of Chinese Science Academy, China. It can automatically estimate astronomical coordinates in real time by CCD star image processing and GPS data processing. The DZT’s errors are analyzed in three aspects, namely, the instrument error, observation error, and data processing error. Reliability and accuracy of DZT integrating GPS and CCD are verified by the practical field operations. Observing results on many unknown points by the repeated observations of each point show the internal precision of the astronomical latitude and longitude. Observing results on several known points and the comparison with the EGM2008-derived results verify the external accuracy of the DZT, and the differences of these points in astronomical latitude and longitude are within ±0.15″ and greater than 1″, respectively.
The impact of COVID-19 on the treatment of obsessive-compulsive disorder
Authors: Palo Amanda , D'Souza Johann M.
Published: August 2021

The COVID-19 pandemic has led to challenges in providing cognitive-behavioral therapy for patients with obsessive-compulsive disorder (OCD). Despite the presence of the pandemic and the risk of contracting illness, therapists can continue to utilize exposure with response prevention (ERP), which is the gold standard psychotherapy treatment for OCD. Therapists can ethically implement ERP by focusing on core treatment tenets while incorporating guidelines recommended by the Centers for Disease Control and Prevention to mitigate risk for COVID-19 exposure. The pandemic has also provided an opportunity to more widely implement ERP through virtual telehealth appointments, which have notable benefits as well as some drawbacks.
Investigate the Intersection of Agriculture & Biotechnology with Timeline Challenge
Authors: Hott Adam , Loftin Madelene
Published: August 2021

Timeline Challenge (https://timelinechallenge.hudsonalpha.org) engages students in a Claim-Evidence-Reasoning (CER) task while they investigate critical advances in agriculture and biotechnology. This freely available digital resource scaffolds students’ investigation of biotechnology by presenting a current and ongoing agricultural problem. The Timeline Challenge utilizes the Progress of Science biotechnology timeline as the backdrop for a series of agriculture-based challenges, such as producing meatier chickens, non-browning apples, or perennial wheat. This web-based module allows students to choose a specific biotech tool to address the challenge and then compare their plan to ongoing modern research related to the challenge. Along the way, students are presented with a real-world complication to encourage thinking about the problem from multiple perspectives.
Chinese Pride and European Prejudice
Authors: Gries Peter , Turcsányi Richard
Published: August 2021

The Chinese government’s cover-up of the origins of the new coronavirus, and its more openly prideful and aggressive foreign and human rights policies, triggered a dramatic deterioration of foreign views of China in 2020. That year also witnessed a significant increase in anti-Chinese/Asian prejudice around the world. Could the former have shaped the latter? Drawing on theories of prejudice and ideology, and using an Autumn 2020 13-nation European survey about China, this paper explores whether increasingly negative attitudes toward Chinese government policies prejudiced European views of local Chinese students, tourists, and communities. It finds substantial evidence of a spillover effect, an effect which is stronger among conservative Europeans than among progressive Europeans more motivated to avoid prejudice. The paper concludes with thoughts on the danger that China’s prideful “wolf warriors” pose for Chinese students, tourists, and local Chinese communities confronting prejudice in Europe today.
Climate impacts on the Gulf of Maine ecosystem
Authors: Pershing Andrew J. , Alexander Michael A. , Brady Damian C. , Brickman David , Curchitser Enrique N. , Diamond Antony W. , McClenachan Loren , Mills Katherine E. , Nichols Owen C. , Pendleton Daniel E. , Record Nicholas R. , Scott James D. , Staudinger Michelle D. , Wang Yanjun
Published: August 2021

The Gulf of Maine has recently experienced its warmest 5-year period (2015–2020) in the instrumental record. This warming was associated with a decline in the signature subarctic zooplankton species, Calanus finmarchicus. The temperature changes have also led to impacts on commercial species such as Atlantic cod (Gadus morhua) and American lobster (Homarus americanus) and protected species including Atlantic puffins (Fratercula arctica) and northern right whales (Eubalaena glacialis). The recent period also saw a decline in Atlantic herring (Clupea harengus) recruitment and an increase in novel harmful algal species, although these have not been attributed to the recent warming. Here, we use an ensemble of numerical ocean models to characterize expected ocean conditions in the middle of this century. Under the high CO2 emissions scenario (RCP8.5), the average temperature in the Gulf of Maine is expected to increase 1.1°C to 2.4°C relative to the 1976–2005 average. Surface salinity is expected to decrease, leading to enhanced water column stratification. These physical changes are likely to lead to additional declines in subarctic species including C. finmarchicus, American lobster, and Atlantic cod and an increase in temperate species. The ecosystem changes have already impacted human communities through altered delivery of ecosystem services derived from the marine environment. Continued warming is expected to lead to a loss of heritage, changes in culture, and the necessity for adaptation.
Single Balloon Enteroscopy-Guided Endoscopic Retrograde Cholangiopancreatography in Surgically Altered Anatomy: Long vs. Short Type
Authors: Park Chang-Hwan
Published: August 2021

Traditionally, enteroscopy-guided endoscopic retrograde cholangiopancreatography (ERCP) was considered as troublesome procedure with high risk of complications in patients with surgically altered anatomy (SAA). However, recent studies have suggested that it might not have to be a foregone conclusion. In addition, various enteroscopes have been used for enteroscopy-guided ERCP in patients with SAA showing promising results. Among them, long type single balloon enteroscopes (SBE) have mostly been used for enteroscopy-guided ERCP in Korea. Recently, short type SBE can come in handy all around. Two major points should be considered when to choose between long type and short type SBE in SAA. First, it is the figurative difference between the two types of SBE that effects on actual results of enteroscopy-guided ERCP. Second, it is clinical studies using short type and/or long type SBE for enteroscopy-guided ERCP in patients with SAA. Conclusively speaking, short type SBE should be considered at first for enteroscopy-guided ERCP in most patients with SAA.
Deep Learning Based Human Presence Detection
Authors: Balachandran Venketaramana , Shapiee Muhammad Nur Aiman , Ab. Nasir Ahmad Fakhri , Mohd Razman Mohd Azraai , P.P. Abdul Majeed Anwar
Published: August 2021

Human detection and tracking have been progressively demanded in various industries. The concern over human safety has inhibited the deployment of advanced and collaborative robotics, mainly attributed to the dimensionality limitation of present safety sensing. This study entails developing a deep learning-based human presence detector for deployment in smart factory environments to overcome dimensionality limitations. The objective is to develop a suitable human presence detector based on state-of-the-art YOLO variation to achieve real-time detection with high inference accuracy for feasible deployment at TT Vision Holdings Berhad. It will cover the fundamentals of modern deep learning based object detectors and the methods to accomplish the human presence detection task. The YOLO family of object detectors have truly revolutionized the Computer Vision and object detection industry and have continuously evolved since its development. At present, the most recent variation of YOLO includes YOLOv4 and YOLOv4 - Tiny. These models are acquired and pre-evaluated on the public CrowdHuman benchmark dataset. These algorithms mentioned are pre-trained on the CrowdHuman models and benchmarked at the preliminary stage. YOLOv4 and YOLOv4 – Tiny are trained on the CrowdHuman dataset for 4000 iterations and achieved a mean Average Precision of 78.21% at 25FPS and 55.59% 80FPS, respectively. The models are further fine-tuned on a  Custom CCTV dataset and achieved significant precision improvements up to 88.08% at 25 FPS and 77.70% at 80FPS, respectively. The final evaluation justified YOLOv4 as the most feasible model for deployment.
The Diagnosis Of Diabetic Retinopathy By Means Of Transfer Learning With Conventional Machine Learning Pipeline
Authors: Mohd Noor Farhan Nabil , Mohd Isa Wan Hasbullah , P.P. Abdul Majeed Anwar
Published: August 2021

Diabetic Retinopathy is one of the common eye diseases due to the complication of diabetes mellitus. Cotton wool spots, rough exudates, haemorrhages and microaneurysms are the symptoms of the diabetic retinopathy due to the fluid leakage that is caused by the high blood glucose level disorder. Early treatment to prevent a permanent blindness is important as it could save the diabetic retinopathy vision. Hence, in this study, we proposed to employ an automated detection method to diagnose the diabetic retinopathy. The dataset was obtained from the Kaggle Database and been divided for training, testing and validation purposes. Furthermore, Transfer Learning models, namely VGG19 were employed to extract the features before being processed by Machine Learning classifiers which are SVM, kNN and RF to classify the diabetic retinopathy. VGG19-SVM pipeline produced the best accuracy in training, testing and validation processes, achieving 99, 99 and 96 percents respectively.
Artur Górski i modernistyczny Lwów. Powinowactwa ideowe
Authors:   Kolegium Literaturoznawstwa, Wydział Filologiczny, Uniwersytet w Białymstoku, Kieżuń Anna
Published: August 2021

The article traces the ideological affinities between Artur Górski (1870–1959), the author of programme Młoda Polska announced in “Życie” (1898) in Cracow, and the modernist Lviv. The author concentrates on the events from the writer’s life in Lviv: his work on Słowacki’s manuscripts (Samuel Zborowski and Zawisza Czarny) in the libraries of Lviv, his continuation of the initiative of Romantic followers, including the legacy of Mickiewicz, as well as Górski’s own popularity with the youth. The article attempts to answer the question why Górski valorized Lviv at the expense of the modernist Cracow, in which his work began.
Gatunek – postać – widzenie. Poetyka Arfa Macieja Szukiewicza
Authors:   Wydział Polonistyki, Uniwersytet Warszawski, Dąbrowska Aleksandra
Published: August 2021

The article analyzes Arf, a drama by Maciej Szukiewicz and one of the least known pieces from the period of Young Poland. The author demonstrates that the world presented results from a complex textual form that oscillates between a fairy tale and a mystery play. These two genological forms constitute an interpretative lens through which the world of real events in the drama is read. The author uses Szukiewicz to illustrate how the framework of drama and the generic patterns bear upon the way in which the readers perceive the storyline.
Flexural properties of blockboard reinforced with glass fiber and various types of fabrics
Authors: Ispas Mihai , Cosereanu Camelia , Zeleniuc Octavia , Porojan Mihaela
Published: August 2021

Flexural properties were evaluated of blockboard with spruce (Picea abies Mill) core and faces made of 2.5-mm fromager (Ceiba pentandra) veneer and 3-mm high-density fiberboard (HDF). For these two types of structures, fiber glass, jute, gauze, and cotton fabrics, were separately bonded under the face layers to improve the strength performance. Flexural properties, modulus of rupture (MOR), and modulus of elasticity (MOE) were determined under laboratory conditions. Improved values were found for MOR and MOE tested in the parallel to core grain direction compared to those perpendicular-to-grain. They were 32% to 49% (MOR) and 39% to 95% (MOE) improvements in case of veneer faces and 142% to 161% (MOR) and 134% to 245% (MOE) improvements in case of HDF faces. The best results of MOR and MOE were obtained for glass fiber used as insertion material, the higher ones being reached for specimens tested in the parallel direction to grain, which were 56.1 N/mm2 (MOR) and 6704 N/mm2 (MOE) for HDF faces. Generally, the improvements were more evident on the blockboard structures with veneer faces oriented perpendicular-to-core grain (30% for MOR and 18% MOE) and for HDF faces with parallel core grain orientation (16% for MOR and 6% MOE).
Strength and stiffness of 8-inch deep mixed hardwood composite timber mats
Authors: Owens Frank C. , Seale R. Daniel , Shmulsky Rubin
Published: August 2021

There is a current and pressing need to develop engineering standards for timber- and other wood-based mats. In 2018 a group of mat producers and users began discussing a potential grading specification standard specific to mats. There are large gaps in the literature regarding the performance of the available raw materials as well as bolt-laminated mat systems. This work represents a novel attempt to begin to assess the mechanical properties of timber mats. Eight-inch deep mixed hardwood timbers were graded according to an experimental specification standard. Then, they were drilled and bolt laminated into 28 three-timber composite mats that were 24 inches (60.96 cm) in width. The bending stiffness (modulus of elasticity [MOE]) and strength (modulus of rupture [MOR]) performance were evaluated with a static bending test. The 5th percentile nonparametric tolerance limit (5% NTL) and design value for fiber stress in bending (Fb) were calculated. The nonparametric design value compared favorably with that of graded timbers, as described in the 2018 National Design Specification (NDS) for wood.
Tuning of adhesion and disintegration of oxidized starch adhesives for the recycling of medium density fiberboard
Authors: Lubis Muhammad Adly Rahandi , Park Byung-Dae , Hong Min-Kug
Published: August 2021

Oxidized starch (OS) adhesives with a balance between their adhesion and disintegration properties were prepared by controlling the degree of oxidation and modifying the cross-linker type and level to replace urea-formaldehyde (UF) resins for easy recycling of medium density fiberboard (MDF). Four molar ratios of H2O2/starch, two types of cross-linker, i.e., blocked-pMDI (B-pMDI) and citric acid (CA), and three levels of the cross-linkers were employed to tailor the performance of the OS adhesives. The OS reacted with the isocyanate groups from the B-pMDI to form amide linkages, while it formed ester linkages by reacting with the CA. The resulting B-pMDI/OS-bonded MDF had better physical and mechanical properties than the CA/OS-bonded MDF, with comparable adhesion (0.34 MPa) to UF resins and ten times greater degree of fiber disintegration than UF resins. The combination of a 0.5 molar ratio OS with 7.5 wt% of B-pMDI produced MDF exhibiting an optimal balance between adhesion and disintegration, suggesting that such OS adhesives could someday replace UF resins in manufacturing and recycling of MDF without formaldehyde emission.
Effect of resin content on the physiochemical and combustion properties of wood fiber insulation board
Authors: Park Se-Hwi , Lee Min , Sun Pureun-Narae , Kang Eun-Chang
Published: August 2021

As petrochemical products (including plastics) contribute to the destruction of the natural environment, the use of such products must be reduced. Plastics account for 90% of the insulation materials used in Korea, including extruded polystyrene (EPS), expanded polystyrene (XPS), and urethane foam. Wood-fiber insulation board (WIB) is a promising natural alternative to petrochemical insulation. This study aimed to determine the optimal amount of adhesive resin required for manufacturing WIB. Fire-resistant WIB was prepared with a melamine-urea-formaldehyde (MUF) resin (ranging from 20% to 35%), and the physicochemical and fire-resistant properties were determined. Higher resin content led to improved physical properties, while the thermal conductivity was unaffected. With the exception of 35% resin content in the WIB, the formaldehyde emissions of the WIB samples complied with the Korean Industrial Standards requirements for Super E0 grade (less than 0.3 mg per L). The physicochemical properties of the WIB samples were sufficient for use as an insulating material, even at 20% resin content. A perpendicular flame test revealed that all samples formed a carbonized layer to prevent flame penetration, except for the specimen with 20% of the resin content. The cone calorimeter testing indicated that the MUF adhesives acted as an effective fire retardant at resin contents above 25%.
Endovascular Parent Artery Occlusion for Intracranial Aneurysms is a Viable, Cost-Effective Alternative: An Institutional Experience from Northeast India
Authors: Phukan Pranjal , Sarma Kalyan , Lynser Donboklang , Sharma Barun Kumar , Baruah Deb Kumar , Saikia Bishwajit , Singh Binoy Kumar
Published: August 2021

Purpose. Endovascular parent artery occlusion (PAO) may be an alternative approach for complex intracranial aneurysm with potentially life-threatening complications. Moreover, the long-term follow-up of the PAO for an intracranial aneurysm is reported sparingly, limited to the case series. It is therefore important to carry out more research on long-term follow-up of the implication of PAO of intracranial aneurysm. The aim of the study was to analyses our experience of PAO for intracranial aneurysms with emphasis on long-term follow-up.Materials and Methods. The data of patients treated with PAO for intracranial aneurysms were reviewed. The outcome was evaluated based on aneurysmal occlusion on immediate angiography, follow-up magnetic resonance angiography (MRA), and complications. The modified Rankin score (mRS) was used to evaluate the functional outcome during the last follow-up. The mean, range, and standard deviation were reported for other variables – the patient’s age, number, and percentage.Results. Endovascular treatment was performed in 178 patients including PAO in 18 patients. Of these 18 (eighteen) patients, there were 13 dissecting aneurysms, 4 mycotic aneurysms, and one traumatic aneurysm.10 (ten) patients underwent PAO for proximal intracranial artery aneurysm and 8 (eight) patients for distal cerebral aneurysms. Complete occlusion of the aneurysm was achieved in 16patients (88.89%) and retrograde filling of the aneurysm was seen in 2 (11.11%) patients. One patient had intraprocedural coil migration resulting in a major infarct with an mRS of 2. Another patient (5.56%) had recanalization of the aneurysm and presented with rupture and intracranial hemorrhage with an mRS score of 4. The mRS of the other 16 patients (88.89%) was zero.Conclusions. Endovascular PAO for cerebral aneurysms was highly feasible and achieved complete occlusion. The morbidity and mortality rates were at the long-term follow-up also acceptable with negligible complications.
Monitoring of radionuclides in water for human consumption in the county of Angra dos Reis
Authors: Gonçalves Mariana Ferreira , Ferreira Ana Cristina de Melo , Oliveira Adriana Belmiro de , Almeida Julio Cesar Toledo de , Cunha Marise Paulina da Silva Alves
Published: August 2021

The radiological impact for members of the population living in Angra dos Reis- RJ was assessed using environmental monitoring data from radium, lead, uranium, thorium and cesium in water for human consumption. For this, were collected and analyzed by radiometry (134Cs and 137Cs), radiochemical (226Ra, 228Ra and 210Pb) and mass spectrometry with inductively coupled plasma (238U and 232Th). From the results, it was observed that the concentrations found were lower than the values established by CONAMA, WHO and the Ministry of Health. It was concluded that the presence of these radionuclides in the collected waters is natural and with levels that are not harmful to health.
Mathematical Modelling of Dynamic System Rotor – Groove Seals
Authors:   G.E. Pukhov Institute for Modelling in Energy Engineering National Academy of Sciences of Ukraine, Shevchenko S.S.
Published: August 2021

Groove seals are considered as hydrostatic bearings that capable of effectively damping rotor vibrations. In order to determine the dynamic characteristics, a model of the rotor–groove seals system is considered. The radial forces and moments in groove seals had been estimated. Expressions of joint radial-angular rotor vibrations in groove seals had been obtained. Formulas had been proposed for constructing amplitude and phase frequency characteristics. An example of calculating the dynamic characteristics of a centrifugal machine rotor model is given.
Електронно-дірковий упорядкований конденсат як пер-спективне лазерне 2D середовище для кімнатних температур
Authors: Lytovchenko V.G. , Fedorenko L.L. , Korbutyak D.V. , Strikha M.V.
Published: August 2021

На основi теоретичних i експериментальних результатiв, отриманих авторами, та детального лiтературного огляду зроблено порiвняльний аналiз процесiв формування i утримування електронно-дiркового (ЕД) екситонного континууму у 3D та 2D напiвпровiдниках. За дiаграмами фазового стану, спектрами фотолюмiнесценцiї i люкс-люксовими залежностями продемонстровано суттєве збiльшення енергiї екситонного зв’язку Eex та стабiльностi ЕД континууму в 2D порiвняно з 3D випадком. Розглянуто вплив визначальних фiзичних чинникiв, вiдповiдальних за пiдвищення Eex та стабiльнiсть ЕД континууму у випадку 2D: зв’язування екситонiв на мiлких домiшкових центрах, сил дзеркального вiдображення та кореляцiйного чинника. Розглянуто особливостi екситонно-поляритонного та електронно-дiркового континуумiв з урахуванням статистик Бозе–Ейнштейна та Фермi–Дiрака з урахуванням можливостi формування e-h кристала. Сформульованi завдання для подальшого теоретичного розгляду, а також названо переваги i перспективи використання макрорезонаторних 2D кювет, що не потребують складної та витратної МПЕ технологiї, для створення оптоелектронних пристроїв нового поколiння.
Реорганізація фрактальної структури пор у порошках детонаційних наноалмазів за високого тиску
Authors: Bulavin L.A. , Tomchuk O.V. , Nagornyi A.V. , Soloviov D.V.
Published: August 2021

Алмазнi наночастинки мають значнi перспективи технологiчних застосувань, тому їх виготовлення та подальша деагрегацiя є актуальною задачею. В данiй статтi за допомогою малокутового розсiяння нейтронiв проаналiзовано пористу структуру агрегатiв у порошках детонацiйних наноалмазiв. Вплив високого тиску дозволив роздiлити внески у малокутове розсiяння вiд мiкро- та нанорозмiрних пор. Визначено тип фрактальних кластерiв, утворених нанопорами. Пiдтверджено можливiсть часткової механiчної деагрегацiї наноалмазних частинок за тиску 1,5 ГПа.
Risk Assessment for Postoperative Pneumonia in Children Living With Neurologic Impairments
Authors: Mpody Christian , Hayes Seth , Rusin Nathan , Tobias Joseph D. , Nafiu Olubukola O.
Published: August 2021

BACKGROUND

Approximately one-third of all pediatric hospital charges are attributable to the care for children living with neurologic comorbidities. These children often require various surgical procedures and may have an elevated risk of lower respiratory infections because of poor neuromuscular coordination, poor cough, uncoordinated swallowing, and poor oral hygiene. Our objective was to evaluate the risk of pneumonia in children presenting with neurologic comorbidities.

METHODS

We performed a retrospective study of children (<18 years) who underwent inpatient surgery between 2012 and 2018 in hospitals participating in the National Surgical Quality Improvement Program. Our primary outcome was the time to incident pneumonia within the 30 days after surgery.

RESULTS

We identified 349 163 children, of whom 2191 developed pneumonia (30-day cumulative incidence: 0.6%). The presence of a preoperative neurologic comorbidity conferred approximately twofold higher risk of postoperative pneumonia (hazard ratio [HR]: 1.91, 95% confidence interval [CI]: 1.73–2.11). We explored the risk of pneumonia conferred by the components of neurologic comorbidity: cerebral palsy (HR: 3.92, 95% CI: 3.38–4.56), seizure disorder (HR: 2.93, 95% CI: 2.60–3.30), neuromuscular disorder (HR: 2.63, 95% CI: 2.32–2.99). The presence of a neurologic comorbidity was associated with a longer length of hospital stay (incidence rate ratio: 1.26, 95% CI: 1.25–1.28).

CONCLUSIONS

The risk of postoperative pneumonia was almost twofold higher in children with neurologic comorbidity. The magnitude of these associations underscores the need to identify areas of research and preventive strategies to reduce the excess risk of pneumonia in children with preoperative neurologic conditions.
La ingeniería agrícola en el mundo
Authors: Hernández H. José Eugenio
Published: August 2021

Con el objeto de dar a conocer el grado de difusión que la ingeniería agrícola tiene en el mundo, en el presente artículo se indican la mayoría de los países y las universidades que en los distintos continentes ofrecen programas de pregrado y postgrado en ingeniería agrícola y áreas afines. Se trata de una recopilación de la información disponible en diferentes fuentes; pretendemos que sirva de punto de apoyo en la obtención de mayores datos para aquellas personas interesadas en iniciar la carrera a nivel de pregrado o bien en cursar estudios de postgrado en una de las áreas específicas de acción profesional de la ingeniería agrícola.
Potencial de secado de yuca con aire natural y energía solar
Authors: Parra Coronado Alfonso , Domínguez Bello Jorge , Caita Rene
Published: August 2021

En este trabajo se presentan los resultados de estudios del potencial de secado de productos agropecuarios con aire natural y energía solar de regiones tropicales, considerando el caso específico de la yuca. La evaluación del potencial de secado de una región se basa en el uso de un programa de computador (Simulación matemática), mediante el cual se obtienen los valores del caudal mínimo de aire requerido para secar el producto antes que éste alcance un nivel de deterioro preestablecido. Otros elementos metodológicos incluyen: manejo de la información meteorológica, mes crítico, patrón de agitación del producto, hora de iniciación del secado, patrón de operación del ventilador, uso de calor suplementario (energía solar) e interpretación de los resultados con el fin de optimizar el sistema. Se presentan mapas para Colombia de líneas isocaudales e isoareas de colector solar plano, con base en los cuales se puede obtener fácilmente la información requerida para el diseño de sistemas de secado de yuca a baja temperatura.
Diagnóstico ambiental preliminar de la Central Termoeléctrica de Paipa
Authors: Martínez Mora Carlos Magno
Published: August 2021

Este trabajo, realizado por el ingeniero Carlos M. Martínez Mora, como uno de los requisitos para optar al título de Magister Scientiae en ingeniería ambiental y dirigido por el ingeniero Jorge Ricardo Bernal, tuvo como objetivo analizar las condiciones actuales de operación de la Central Termoeléctrica de Paipa y establecer las bases para la preparación del expediente ambiental exigido por el Código de los Recursos Naturales Renovables y de Protección al Medio Ambiente.
Se estableció que en el momento operan tres unidades de generación de 33, 66 y 74 megavatios. Se utiliza el agua del río Chicamocha, para condensación y transferencia de calor hacia el ambiente. El combustible utilizado es carbón mineral, cuyas emisiones contaminadoras son cenizas y óxidos de azufre. Se llevó a cabo un programa de muestreo de calidad del agua y se hizo un estimativo de calidad del aire, mediante la aplicación de un modelo de dispersión. Definido el estado actual o de referencia, se realizó un análisis de los efectos predecibles que podría causar sobre la calidad ambiental, la instalación de una cuarta unidad generadora de 150 megavatios. Se hacen varias recomendaciones tendientes a minimizar tales posibles efectos negativos.
Determinación del potencial depurador del cultivo hidropónico de Phalaris spp y Pennisetum clandestinum Hochst, mediante la técnica de la película nutriente
Authors: Cruz Torres Luis Eduardo , Cuervo Flor Mariela , Sanabria Doris Yolanda
Published: August 2021

El presente estudio corresponde a la segunda etapa de la evaluación de un sistema de tratamiento de aguas residuales domésticas conocido como la Técnica de la Película Nutriente (TPN), utilizando dos especies de gramíneas: Pennisetum clandestinum Hochst (pasto kikuyo) y Phalaris spp (pasto brasilero). Los resultados permitieron establecer que las raíces actúan como un filtro biológico de los sólidos y materia orgánica, y además absorben los nutrientes contenidos en este tipo de aguas residuales. Por otra parte, el establecimiento de una cadena trófica o “cadena depuradora" de organismos (plancton y fauna asociada) contribuye en gran medida en la remoción de polutantes. Bajo las condiciones de operación, el sistema de tratamiento (TPN) removió eficientemente bacterias coliformes de origen fecal, seguido por solidos suspendidos, materia orgánica y en menor grado los nutrientes.
Un método eficiente para la solución del flujo de carga radial
Authors: Díaz M. Hernando
Published: August 2021

En este trabajo se presenta un método para la solución del flujo de carga en sistemas radiales, balanceados o no. El método está basado en el algoritmo clásico de flujo de carga con la matriz de Impedancia (ZBus). Sin embargo, no requiere el almacenamiento de esta matriz; el efecto de multiplicar por ella se logra mediante un procedimiento muy simple. También se obtuvo una interpretación física sencilla de este procedimiento. Se propone también una relación entre los métodos de Doble Barrido y el producto de un vector por la matriz de impedancia.
Alienación y nuevas tecnologías
Authors: Rey Romero Álvaro
Published: August 2021

Las nuevas tecnologías están provocando un impacto social y cultural en los trabajadores. Aquí se aportan algunos elementos para la discusión sobre sus beneficios y desventajas.
DANAE: simulador de propiedades fisicoquímicas como una combinación entre la racionalización más pura y profunda y la medición experimental más tactual y empírica.
Authors: Bogoya Maldonado Daniel , Quintero T. Angela , Mutis García Omar
Published: August 2021

Este articulo pretende ilustrar una combinación entre la razón y la experiencia para estimar propiedades fisicoquímicas, útiles para el cálculo de balances de materia y energía, de uso frecuente en Ingeniería química. Igualmente, presenta el sistema DANAE, desarrollado para calcular Interactivamente por microcomputador seis propiedades de compuestos puros y cinco de mezclas (hasta de quince componentes), basado en un banco de datos (de tamaño 250 KB) y dos programas principales (de tamaño 80 KB).
Desarrollo de herramientas para el análisis de sistemas de distribución
Authors: Parra Estrella , Díaz Hernando , Flórez Lucio
Published: August 2021

En este trabajo se describe una herramienta computacional muy eficiente para el análisis de sistemas de distribución. Como parte del proyecto fue desarrollado un método original para la modelación de estos sistemas. La técnica usual, basada en componentes simétricas, no es aplicable a estos sistemas, puesto que las redes de secuencia resultan acopladas. El modelo presentado no sufre de estos inconvenientes. Usando estos modelos y de otras propiedades de las matrices de red, se desarrolló un método original para la solución de flujos de carga radiales, balanceados o no. El método es muy simple y rápido y su convergencia es muy confiable. Para el análisis de fallas fueron desarrollados dos algoritmos de cálculo: El primero se basa en componentes de fases. El segundo algoritmo, basado en los modelos desarrollados en la primera parte, representa una solución original y muy eficiente al problema del cálculo de cortocircuito.