bluuebunny/crossref_metadata_2025 huggingface dataset:
Low‐Dose Trazodone, Benzodiazepines, and Fall‐Related Injuries in Nursing Homes: A Matched‐Cohort Study
Authors: Bronskill Susan E. , Campitelli Michael A. , Iaboni Andrea , Herrmann Nathan , Guan Jun , Maclagan Laura C. , Watt Jennifer , Rochon Paula A. , Morris Andrew M. , Jeffs Lianne , Bell Chaim M. , Maxwell Colleen J.
Published: September 2018

Objectives

To evaluate whether risk of fall‐related injuries differs between nursing home (NH) residents newly dispensed low‐dose trazodone and those newly dispensed benzodiazepines.

Design

Retrospective, matched cohort study in linked, population‐based administrative data. Matching was based on propensity score ( ± 0.2 standard deviations of the score as a caliper), age ( ± 1 year), sex, frailty status, and history of dementia. The derived propensity score included demographic characteristics, clinical comorbidities, cognitive and functional status, and risk factors for falls.

Setting

All NHs in Ontario, Canada.

Participants

Propensity score–matched pairs of residents aged 66 and older who received a full clinical assessment between April 1, 2010, and March 31, 2015 (N=7,791).

Measurements

Hospitalization (emergency department visit or acute care admission) for a fall‐related injury within 90 days of exposure. Subdistribution hazard functions accounted for competing risk of death. Sensitivity analyses were used to examine falls resulting in hip or wrist fracture only, as well as different lengths of follow‐up at 30, 60, and 180 days.

Results

Cumulative incidence of a fall‐related injury in the 90 days after index was 5.7% for low‐dose trazodone users and 6.0% for benzodiazepine users (between‐group change=–0.29, 95% confidence interval (CI)=–1.02–0.44]; hazard ratio=0.94, 95% CI=0.83–1.08). Findings were consistent across sensitivity analyses.

Conclusion

New use of low‐dose trazodone was no safer with respect to a risk of a fall‐related injury than new use of benzodiazepines. Additional studies to compare the effectiveness and risks of low‐dose trazodone with those of a variety of psychotropic drug therapies are required in light of increasing trends in the use of trazodone in NHs.
Individual differences in emotion regulation goals: Does personality predict the reasons why people regulate their emotions?
Authors: Eldesouky Lameese , English Tammy
Published: September 2018

Objective

We investigated how the Big Five traits predict individual differences in five theoretically important emotion regulation goals that are commonly pursued—pro‐hedonic, contra‐hedonic, performance, pro‐social, and impression management.

Method

We conducted two studies: (a) a large survey study consisting of undergraduates (N = 394; 18–25 years; 69% female; 56% European American) and community adults (N = 302; 19–74 years; 50% female; 75% European American) who completed a newly developed global measure of individual differences in emotion regulation goals and (b) a 9‐day daily diary study with community adults (N = 272; 23–85 years; 50% female; 84% European American) who completed daily reports of emotion regulation goals. In both studies, participants completed a measure of the Big Five.

Results

Across global and daily measures, pro‐hedonic goals and pro‐social goals were positively associated with Agreeableness, performance goals were positively associated with Openness, and impression management goals were positively associated with Neuroticism. Globally, contra‐hedonic goals were also negatively associated with Agreeableness and Conscientiousness.

Conclusions

The Big Five systematically predict the emotion regulation goals people typically pursue. These findings have important implications for understanding why people engage in certain forms of regulatory behavior and why personality has consequences for well‐being.
Unstimulated saliva: Background noise in taste molecules
Authors: Feron Gilles
Published: September 2018

Saliva is a highly complex bodily fluid composed of many proteins, peptides, small organic molecules, and ions. Saliva is produced and secreted by the major and minor salivary glands to protect the mouth and to participate in digestion. Generally, a distinction is made between unstimulated saliva that is a result of autonomic stimulation and stimulated saliva that is produced during chewing and taste stimulation. The link between saliva and sensory perception can thus be regarded in two ways: the role of unstimulated saliva as a background taste and the mechanistic role of stimulated saliva during eating. Indeed, unstimulated saliva (and its components) is continuously bathing our oral cavity and as such stimulates our taste receptors, thus playing a role in taste sensitivity. However, the role of unstimulated salivary components in mediating taste has been studied only in very few substances. To explore this question, this review attempts to compare data from the literature on unstimulated salivary composition with those on taste sensitivity. The main conclusion centres around the concept that the gustatory self‐adaptation phenomenon may be relevant for only a few salivary compounds. Further studies at the level of the salivary Von Ebner glands and salivary pellicle are necessary before arriving at definitive conclusions on this subject.

Practical application

Unstimulated saliva contains taste substances that can influence sensory perception through taste adaptation. However, large inter‐individual variability exists in unstimulated salivary composition both qualitatively and quantitatively. These differences may explain the variability in taste perception and thus the food choices and behaviors of an individual. Thus, in the context of providing personalized food and nutrition to the consumer, variability of unstimulated saliva should be considered for specific formulation of food products.
Stimulatory effect of dietary clove, Eugenia caryophyllata, bud extract on growth performance, nutrient utilization, antioxidant capacity, and tolerance of African catfish, Clarias gariepinus (B.), to Aeromonas hydrophila infection
Authors: Adeshina Ibrahim , Jenyo‐Oni Adetola , Emikpe Benjamin O. , Ajani Emmanuel K. , Abdel‐Tawwab Mohsen
Published: September 2018

The occurrence of pathogenic bacteria, Aeromonas hydrophila, in farm‐raised fish requires urgent attention. Continuous and indiscriminate use of antibiotics as growth promoters and disease control agents in aquaculture have been discouraged because of the risk of development of antibiotic‐resistant bacterial strains. There is steady interest in the use of botanicals, such as clove, Eugenia caryophyllata, buds extract (ECBE), as alternatives. Hence, the present study evaluated the effect of dietary ECBE supplementation on the growth performance, physiological, antioxidant, and immunity biomarkers of African catfish, Clarias gariepinus. Fish (11.7 ± 0.5 g) were fed diets containing 0.0 (control), 5.0, 10.0, or 15.0 g ECBE/kg diet up to apparent satiation twice daily for 12 weeks. After the feeding trial, fish from each treatment were challenged with A. hydrophila infection by intraperitoneal injection and kept under observation for 14 days to record any abnormal clinical signs and daily mortality. The results demonstrated that fish performance and feed intake were significantly enhanced with increasing ECBE levels, and its optimum level is 15 g/kg diet. Further, the dietary ECBE increased significantly the intestinal villi length/width and absorption area in a dose‐dependent manner. There are significant progressive increases in the values of red blood cells, hemoglobin, hematocrit, white blood cells, platelets, lymphocytes, and heterocytes, while monocytes, eosinophil, and basophils decreased significantly due to dietary ECBE in a dose‐dependent manner. Highest glucose, cholesterol, total protein, globulin, and albumin‐globulin ratios, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), urea, and creatinine values were found in fish fed 15 g ECBE/kg diets, while lowest values were recorded in fish fed the control diet. Despite the high AST and ALT values, no visible lesions or damage were observed in the liver cells of fish fed ECBE‐enriched diets. In addition, the inclusion of ECBE in fish diets enhanced the antioxidant and immunity capacity. Fish mortality after the bacterial challenge was higher in fish fed the control diet (82.3%) than those fed ECBE‐enriched diets. The lowest fish mortality was observed in fish fed the 15 ECBE/kg diet (4.7%) [Correction added on 16 November 2018: this section has been revised for clarity.].
Reducing NAFLD‐screening time: A comparative study of eight diagnostic methods offering an alternative to ultrasound scans
Authors: Procino Filippo , Misciagna Giovanni , Veronese Nicola , Caruso Maria G. , Chiloiro Marisa , Cisternino Anna M. , Notarnicola Maria , Bonfiglio Caterina , Bruno Irene , Buongiorno Claudia , Campanella Angelo , Deflorio Valentina , Franco Isabella , Guerra Rocco , Leone Carla M. , Mirizzi Antonella , Nitti Alessandro , Osella Alberto R. ,   MICOL GROUP
Published: September 2018

Background & Aims

The use of ultrasound scan (US) in non‐alcoholic fatty liver disease (NAFLD) screening overloads US waiting lists. We hypothesized and tested a hybrid two‐step method, consisting of applying a formula, to exclude subjects at low risk, before US.

Methods

The sample included 2970 males and females (937 with NAFLD) diagnosed by US. We selected eight formulas: Fatty Liver Index (FLI), Hepatic Steatosis Index (HIS), body mass index (BMI), waist circumference (WC), Abdominal Volume Index (AVI), waist‐to‐height ratio (WHtR), waist/height0.5 (WHT.5R) and Body Roundness Index (BRI), and calculated their performance in the two‐step method evaluating percentage reduction of the number of liver US (US reduction percentage), percentage of false negative and percentage of NAFLD identified.

Results

The US reductions percentage were 52.2% (WHtR), 52.1% (HIS), 51.8% (FLI), 50.8% (BRI), 50.7% (BMI and WHt_5R), 46.5% (WC) and 45.2% (AVI). The false negative percentage were 8.5% (WHtR), 7.9% (BRI), 7.3% (WHt_5R), 7.2% (BMI), 6.7% (HIS), 6.6% (FLI), 5.6% (WC) and 5.2% (AVI). The best percentage of NALFD identified was obtained using AVI (83.6%) before US, then WC (82.2%), FLI (79%), HIS (78.9%), BMI (77.3%), WHt_5R (76.9%), BRI (74.8%) and WHtR (73%).

Conclusion

The best formula to use in two‐step diagnostic NAFLD screening was AVI, which showed a low false negative rate and a higher percentage of identified NAFLD. Other studies evaluating the economic advantages of this screening method are warranted.
ANTIOBJECTS
Authors: Dever Josh
Published: September 2018

Aristotle observes that substances have no contraries. Consider one possible role that the contrary of a substance might play, were it to exist. Just as objects serve as guarantors of the instantiation of properties, contraries of objects could serve as guarantors of the non‐instantiation of properties. By first considering a reframing of deontic logic that takes ‘being permitted’ rather than ‘being forbidden’ as the default state, I develop logical tools that allow the construction of extremal models in which everything is permitted and nothing is forbidden. Transferred to quantified logic, these same tools give us a conception of antiobjects which block property instantiation. The resulting picture of antiobjects is then used as a test case to examine questions about the role of symmetry considerations in philosophical methodology.
Primary pulmonary histiocytic sarcoma in dogs: A retrospective analysis of 37 cases (2000‐2015)
Authors: Marlowe Katelyn W. , Robat Cecilia S. , Clarke Dawn M. , Taylor Angela , Touret Maude , Husbands Brian D. , Vail David M.
Published: September 2018

Primary pulmonary histiocytic sarcoma (PHS) has been reported, but is not well characterized. The aim of this retrospective study was to describe clinical characteristics, characterize prognostic factors and report the outcome of a larger group of dogs with primary PHS. Medical records of dogs diagnosed with primary PHS at 11 institutions were retrospectively reviewed. Thirty‐seven dogs were included; 13 received CCNU‐based chemotherapy alone, 18 received surgery and adjuvant CCNU‐based chemotherapy, 3 received medical management alone and 3 dogs received surgery alone. The overall median progression free survival (PFS) and the median survival (overall survival [OS]) were 197 and 237 days, respectively. Measurable responses were noted in dogs receiving only chemotherapy; however, responses were not durable with PFS (91 days) and OS times (131 days) shorter than overall medians. Dogs that received surgery and chemotherapy had significantly prolonged PFS (276 days,P = 0.001) and OS (374 days,P = 0.001), compared with dogs not receiving surgery. As only three dogs undergoing surgery did not receive chemotherapy, it is not possible to determine the contribution of chemotherapy as an adjuvant to surgery. Dogs without evidence of intra‐thoracic metastatic disease were much more likely to undergo surgery (odds ratio = 7.04;P = 0.018). While the presence of metastasis or clinical signs at diagnosis negatively impacted PFS, only the former negatively impacted OS. These data imply that dogs presenting with PHS amenable to surgery (ie, no clinical evidence of metastasis) benefit from surgical intervention; however, the lack of a comparable surgery alone group precludes assessment of the efficacy of post‐surgical adjuvant chemotherapy.
Risen from Ruins
Authors: Stangl Paul
Published: September 2018

This book examines city building in East Berlin from the end of World War II on May 8, 1945, until the construction of the Berlin Wall on August 13, 1961—a period of great interest in reshaping the city to express new political ideals. It examines how key decision-makers were influenced by their worldview and political ideology; beliefs about the relationship between urban form and society including formal theories; political strategizing at municipal, national, and international levels; and assessments concerning the deployment of limited resources. The book emphasizes how extant discourses acted as “pathways of memory,” shaping the way key actors attributed meaning to different elements of the urban landscape. The East German approach to creating a new city and a new society did not neatly mimic the Soviet model, and it did not emerge in a creative flash. Rather, the city planning and building depended upon the selective application of existing discourses based on cultural and political leaders’ personal knowledge, beliefs, and preferences, their assessments of contemporary political and material conditions, and their view regarding long-term development. Novelty would arrive in how cultural and political leaders combined these elements and how some frameworks were adapted over time.
Revolution in the Terra do Sol
Authors: Sarzynski Sarah
Published: September 2018

This book recasts conventional narratives of the Cold War in Brazil and the 1964 coup through its examination of revolutionary social and cultural movements in the Northeastern region in the 1950s and 1960s. During this period, hundreds of thousands of rural men and women protested in the streets, on the plantations, and in the courtrooms for land, labor, and citizenship rights. In the wake of the Cuban Revolution, the strength of the rural social movements raised hopes and fears about the potential for social revolution in Brazil. Rural social movements, Conservative landowners, politicians, and filmmakers debated agrarian reform in a language of regional historical symbols and themes. The repetition of such symbols and themes in popular culture and political discourse drew from the trope of o Nordeste, defining the region and its people as the backwards, impoverished, fatalistic, violent, traditional Other in contrast to the modern, urban Brazilian nation. Even if rural social movements and radical filmmakers attempted to rework and assert new meanings of o Nordeste, often the images they produced served to further entrench assumptions and stereotypes of the region and its people. This book shows how such narratives and stereotypes were deliberately deployed as political tools to empower certain groups in Brazilian society while disenfranchising others. It reveals how discriminatory assumptions about rural Northeasterners as impoverished, non-modern victims and violent fanatics legitimized the state persecution of rural social movements, provided a rationale for the military coup and shaped the way Cold War history has been told.
Eugène Viollet-le-Duc : une oeuvre entre restauration et création.
Authors: Gaussuin Bérénice
Published: September 2018

L’architecte Eugène Viollet-le-Duc a été un créateur bâtisseur dont le terrain d’expérimentation principal était le mo­nument historique. De son premier chantier à la Madeleine de Vézelay – qu’il prend en charge à 26 ans – jusqu’à la publication en 1866 de son article « Restauration », en passant par la restauration de la cathédrale Notre-Dame de Paris, il a élaboré grâce à la pratique, une méthodologie parallèlement à sa théorie rationaliste et à sa théorie de la restauration. La progression de cette théorie passe de la prudence, de la modestie de l’artiste face à l’histoire, à un éloignement des archéologues pour faire entrer le projet d’architecture dans le monument historique. Viollet-le-Duc a étudié sans relâche la matière du bâti historique, dans le but de la fait plier à ses objectifs théoriques et doctrin­aux. Dans son approche du projet, Viollet-le-Duc s’est positionné en praticien maîtrisant son chantier quel qu’en soit l’objet : monuments historiques ou créations ex-nihilo, il a transfèré les méthodes, les équipes, les formes pour que la création participait de la restauration.
Salas de cine en Santiago de Chile : teatros, “barracones” y coliseos, 1896-1940
Authors: Iturriaga Echeverría Jorge
Published: September 2018

El presente trabajo recorre la evolución de las salas de cine en Santiago de Chile, en las primeras décadas del fenó­meno cinematográfico, a partir de tres dimensiones de análisis, cuales son la ubicación territorial, la organización interna y la interacción social. A partir de esa perspectiva y en base a recopilación de información en prensa y revistas de la época, el artículo propone la existencia sucesiva de tres tipos de establecimientos: los teatros oligárquicos, los biógrafos populares y los coliseos masivos. En base a esos resultados, el texto habla fundamentalmente de lo dinámica y conflictiva que fue la emergencia de la sociedad de masas en Chile, que se movió desde un paradigma oligárquico hacia uno de fuerte impronta popular.
El espacio de articulación urbana-rural de Buenos Aires en el siglo XIX
Authors: López Goyburu Patricia
Published: September 2018

A lo largo de la historia de Buenos Aires se observan diferentes tipos de articulación entre el sistema urbano y el rural. En el presente trabajo se exponecómo se ve y se proyecta la relación entre el sistema urbano y el rural en esa ciudad durante el siglo XIX. Para ello, es necesario remitirse al estudio de los documentos urbanísticos y bibliográficos que abordan esta época. El estudio muestra que la cartográfica fue el instrumento utilizado para geometrizar el territorio, lo que facilitó el control técnico y administrativo.
Rentabilidad de la inversión en vivienda en Medellín durante 2016
Authors: Jaramillo Montoya Sergio Andrés , Agudelo Torres Jorge Enrique
Published: September 2018

El desarrollo del sector inmobiliario ha acaparado la atención de investigadores e inversionistas alrededor del mundo durante décadas, lo que propicia la aparición de una gran cantidad de artículos relacionados con el tema; sin embargo, en Colombia es difícil encontrar este tipo de trabajos, pues como consecuencia de los problemas de seguridad existentes, la información del sector no es conocible con facilidad. El principal hallazgo del estudio radica en que las tasas de capitalización de la vivienda son más altas en aquella ubicada en los estratos más bajos e inferiores en las localizadas en los estratos más altos. La alta demanda de viviendas en alquiler en los estratos bajos y la poca oferta generan alta rentabilidad, contrario a lo que ocurre en los estratos altos.
El flâneur bogotano contemporáneo: Reflexiones sobre el deambular en los espacios comerciales de Bogotá
Authors: Quijano Gómez Estefanía
Published: September 2018

El flâneur es conocido como una figura urbana parisina del siglo XIX que encarnaba un cierto tipo de vida y de relación con la ciudad, en especial con espacios comerciales, en tanto transeúnte y observador. En la actualidad, la ciudad ha cambiado sus dinámicas y es considerada como un espacio para el consumo, más que un espacio para el deambular, por lo que con el nacimiento de la cultura de masas y la sociedad de consumo el flâneur se consideró extinto. Por medio de este artículo se busca demostrar que la figura del flâneur está vigente y explica la relación del peatón con los espacios comerciales en una ciudad latinoamericana: Bogotá. Se analizan dos casos específicos: el deambular por los pasajes al aire libre y el consumir en los centros comerciales. Por último, se propone una reflexión en cuanto a la experiencia del paseante en la ciudad contemporánea.
Introducción a los metromarxismos geográficos latinoamericanos: Perspectivas sobre la ciudad, lo urbano y la urbanización
Authors: Santana Rivas Luis Daniel
Published: September 2018

Las teorías urbanas afrontan un momento de crisis a causa de la tendencia a la urbanización total de la sociedad, por lo que algunas de sus categorías fundacionales como la de ciudad, lo urbano y la urbanización están siendo cuestionadas. En América Latina, el carácter de viudez espacial que caracteriza a las teorías urbanas críticas es un obstáculo para afrontar esos cuestionamientos; por ello, el objetivo del presente artículo es dar cuenta de diferentes categorías de la ciudad, lo urbano y la urbanización propuestos desde lo que se denomina metromarxismos geográficos latinoamericanos. Tras una revisión de cinco autores, se concluye que la teorización sobre la producción de los espacios urbanos se ha movido desde un enfoque estructuralista a una variedad de marxismo dialéctico menos dogmático y más abierto a la experimentación teórica y metodológica.
Medición de la cobertura y la accesibilidad del espacio público en Bogotá, Medellín y Cali
Authors: Mayorga José Mario , Hernández Laura
Published: September 2018

El siguiente artículo pretende evaluar las coberturas de espacio público de las tres ciudades principales de Colombia, mediante la construcción de un indicador de accesibilidad y capacidad de espacio público. Se toma como punto de partida el diseño de una red de accesibilidad para determinar las proporciones disponibles de espacio público por habitante de acuerdo con su lugar de residencia. Los escenarios obtenidos denotan la alta inequidad en la distribución de este atributo urbano respecto a la concentración de la población, lo cual incide en las oportunidades de potenciación de la calidad de vida.
Al participar se hace ciudad en el entretanto. Urbanismo emergente en Bilbao*
Authors: Garrido Díez Almudena
Published: September 2018

Durante las tres últimas décadas se ha llevado a cabo un urbanismo definido por megaproyectos y una planificación top-down sin participación real de la ciudadanía. Con el objetivo de investigar el papel de esta última en la transformación del espacio público y en la reconstrucción de las relaciones sociales, se analiza un proceso de participación de un movimiento social urbano en la península de Zorrotzaurre, Bilbao, a lo largo de una década (2004-2014). Mediante la metodología investigación-acción y técnicas cualitativas como la narrativa longitudinal (2004- 2016) y multicapa (actores institucionales, económicos y sociales) en la primera fase y entrevistas semiestructuradas en la segunda, descubrimos que es ardua la tarea de construir espacios de poder deliberativos para la ciudadanía y que es en los nuevos espacios de encuentro creados por un aprendizaje social en donde puede surgir un cambio de paradigma en la construcción de nuestras ciudades.
Flow Analysis of a Porous Polymer-Based Three-Dimensional Cell Culture Device for Drug Screening
Authors: Ma Liang , Gao Lei , Luo Yichen , Yang Huayong , Zhang Bin , Zhou Changchun , Ock JinGyu , Li Wei
Published: September 2018

A porous polymer-based three-dimensional (3D) cell culture device has been developed as an in vitro tissue model system for the cytotoxicity of anticancer drug test. The device had two chambers connected in tandem, each loaded with a 3D scaffold made of highly biocompatible poly (lactic acid) (PLA). Hepatoma cells (HepG2) and glioblastoma multiforme (GBM) cancer cells were cultured in the two separate porous scaffolds. A peristaltic pump was adopted to realize a perfusion cell culture. In this study, we focus on cell viability inside the 3D porous scaffolds under flow-induced shear stress effects. A flow simulation was conducted to predict the shear stress based on a realistic representation of the porous structure. The simulation results were correlated to the cell variability measurements at different flow rates. It is shown that the modeling approach presented in this paper can be useful for shear stress predication inside porous scaffolds and the computational fluid dynamics model can be an effective way to optimize the operation parameters of perfused 3D cell culture devices.
Efficient CNC Tool Path Planning Using Point Cloud
Authors: Ghogare Sumedh , Pande S. S.
Published: September 2018

This paper reports the development of an efficient iso-scallop tool path planning strategy for machining of freeform surfaces on a three axis CNC milling center using the point cloud as the input. Boundary of the point cloud is chosen as the Master Cutter Path, using which the scallop points are computed. Adjacent side tool paths are computed using these scallop points and the path planning process is completed till the entire surface is covered. The system generates post-processed NC program in ISO format which was extensively tested for various case studies. The results were compared with the iso-planar tool path strategy from commercial software. Our system was found to generate efficient tool path in terms of part quality, productivity and storage memory.
Dynamic Importance Analysis of Components of Complex Mechanical System by Small Sample Data
Authors: Yangfan Li , Yingjie Zhang , Bochao Dai , Lin Zhang
Published: September 2018

Importance analysis deals with the influence of individual system component on system operation. Thus, a lot of failure data should be collected to make the analysis more accurate. This paper mainly focuses on the numerical estimation of component importance in complex mechanical system which is considered as a multi-state system with few failure data. In order to evaluate components’ failure probability distribution by small sample data, a time integral importance measure (TIIM) approach is proposed. In this measure, we aim to measure component importance using the change of system performance caused by wiping off component failure data. On this basis, the dynamic importance fluctuation of a component can be measured by calculating criticality of each state of the component. The approach has been verified by probability analysis of CNC machine tools. The main contribution of this work is the proposed dynamic importance measure which can be used to identify the key state of a component that influences system performance most by small-sample data.
Joint Formation in Multi-Layered Ultrasonic Welding of Ni-Coated Cu and the Effect of Preheating
Authors: Luo Ying , Hu S. Jack , Kannatey-Asibu Elijah , Chung Haseung , Cai Wayne , Rinker Teresa , Abell Jeffrey
Published: September 2018

Multi-layered ultrasonic welding (USW) is widely used in joining of electrodes or tabs in lithium-ion batteries. To achieve quality joints and enhance the welding process robustness, an improved understanding of the joint formation is highly desirable. In this paper, USW of 4-layered Ni-coated Cu is studied to investigate the joint formation at a single interface and joint propagation from interface to interface under both ambient and preheated conditions. The results indicate that joint formation involves three major mechanisms: Ni-Ni bonding with minimal mechanical interlocking, Ni-Ni bonding with moderate mechanical interlocking, and a combination of Ni-Ni bonding, Cu-Cu bonding, and severe mechanical interlocking. Results also show that joints propagate from the interface close to the sonotrode side to that close to the anvil side. It is further observed that the joint formation can be accelerated and the joint strength can be improved with process preheating, especially at the interface closest to the anvil. The effect of preheating is most significant during the early stage of the process, and diminishes as process progresses. The favorable effects of preheating improve the robustness of multi-layered USW.
Process Monitoring of 3D Metal Printing in Industrial Scale
Authors: Amini Mohammadhossein , Chang Shing
Published: September 2018

Metal 3D printing is one of the fastest growing additive manufacturing (AM) technologies in recent years. Despite the improvements and capabilities, reliable metal printing is still not well understood. One of the barriers of industrialization of metal AM is process monitoring and quality assurance of the printed product. These barriers are especially much highlighted in aerospace and medical device manufacturing industries where the high reliability and quality is needed. Selective Laser Melting (SLM) is one of the main metal 3D printing methods where it is known that more than 50 parameters are affecting the quality of the print. However, the current SLM printing process barely utilize a fraction of the collected data during production. Up to this point, no study to the best of our knowledge examines the correlation of factors affecting the quality of the print. After reviewing the current state of the art of process monitoring for metal AM involving SLM, we propose a method to control the process of the print in each layer and prevent the defects using data-driven techniques. A numerical study using simulated numbers is provided to demonstrate how the proposed method can be implemented.
Optimization of Drill Bits for Bone Drilling Procedure
Authors: Sui Jianbo , Sugita Naohiko
Published: September 2018

The paper presents a methodology to optimize drill bits to realize safe drilling of bone materials for many surgeries like orthopedics and neurosurgery. First, a mechanistic model is introduced to relate drilling forces to main drill bit geometry parameters. Then a genetic algorithm is developed to optimize drill bit geometry parameters by minimization of drilling forces based on the mechanistic model. Finally prototypes of drill bits with optimized geometry parameters are produced and drilling experiments are conducted to verify the advantages of these new drill bits. The results show that by comparison with normal drill bit, the average drilling forces are reduced to more than 50% by drill bits with optimized geometry parameters under a wide range of drilling conditions.
The Microstructural Origin of Sinuous Flow in Metal Cutting
Authors: A. Salilkumar Vandana , Sundaram Narayan K.
Published: September 2018

In situ, high-speed imaging experiments have revealed the existence of sinuous flow, a recently discovered mode of chip formation in machining. The origin and consequences of sinuous flow are still being investigated, but it is now known that sinuous flow involves extensive redundant plastic deformation, poor surface finish and paradoxically high cutting forces. Here, we use full-scale simulations to show that microstructure related inhomogeneity is a major cause of sinuous flow. The simulations are conducted in a Lagrangian FE framework, and use a simple pseudograin model to represent the metal workpiece as a polycrystalline aggregate. The model successfully captures all essential features of sinuous flow in metals like OFHC copper and CP aluminum, and points to the importance of including material microstructure in cutting simulations.
Template-Free Fabrication of Aligned Nanoarray for Quantifying the Nanosurface-Single Cells Interaction
Authors: Wang Biran , Wang Liming , Wang Shiren
Published: September 2018

In this paper, we for the first-time synthesized vertically aligned polyaniline (PANI) nanowire arrays on flat-end AFM tips via template-free solution methods. 4-Aminothiophenol was used for tailoring the nucleation size, chain propagation and orientation of the PANI nanowires. The microscopy characterization indicated that diameter was centered at a mean of 33.7 nm with a standard deviation of 6.5 nm, and length was centered at a mean of 50.3 nm with a standard deviation of 7.6 nm. PANI nanowire arrays are non-toxic, low-cost, and tunable, and thus PANI nanowire-grown tips could perfectly simulate different nanosurfaces. Via the force spectroscopy, we demonstrate the feasibility in quantifying the nanostructure-cell interactions at the single cell level in real time with high reliability and accuracy. This work will enable a new tool in precisely quantifying the interactions of single living cells and nanosurface, and thus opens a new door to understand how single living cells sense and respond to the specific nanostructures.
Improvement in Micro Feature Generation in ECDM Process With Powder Mixed Electrolyte
Authors: Paul Lijo , Kumar Arun B.
Published: September 2018

Electrochemical discharge machining (ECDM), also known as spark assisted chemical engraving (SACE), is an effective micro-machining process for machining of electrically nonconducting materials. It involves melting and etching process under the high electrical discharge on the electrode tip during electrolysis that enables the ECDM process to machine very hard and non-conducting materials such as borosilicate glass, quartz, ceramics etc. efficiently and economically. In the current study micro holes are machined on borosilicate glass with an electrolyte mixed with graphite powder. The conductive graphite powder in electrolyte has shown improvement in machining with more quantity of spark during machining. The main parameters taken in the study are voltage, tool rotation and duty factor along with concentration of powder in electrolyte. The main output responses taken in the study are Material Removal Rate (MRR) and lower Radial Overcut (ROC) along the machined holes. A multi-objective optimization is carried out for higher MRR and lower ROC with Grey Relation Analysis (GRA) in order to obtain the best parameters combination. From the experimental study the optimum values of parameters for MRR and ROC are found to be, voltage of 40 V, Graphite powder concentration 1.25% by weight, duty factor 70% and tool rotation of 500 rpm. From the microscopic images of the machined surface, presence graphite powder in electrolyte has improved the machined features due to its conductive nature.
Stress State Control by a Novel Bending Process and its Effect on Damage Evolution
Authors: Meya Rickmer , Löbbe Christian , Tekkaya A. Erman
Published: September 2018

The novel sheet metal bending process is designed to change the load path in order to control the damage evolution. The process superposes targeted radial stresses during bending and is therefore called radial stress superposed bending, short RSS-bending. As material damage is strongly dependent on the load path, the setting of this property becomes possible in this process. Hence, the process principle, its features and the tool setup are presented. Furthermore, numerical simulations are carried out with the aim to investigate the occurring deformation zone and the resulting radial stress superposition. Scanning electron micrographs prove that the evolution of voids is delayed. With the acquired knowledge to change the stress state during the bending process, the property ‘damage’ can be controlled and finally reduced. This enhances the microstructure and lifetime performance of the bent product.
Electrohydrodynamic Casting Polymeric Carbon Nanofibers From Different Precursors for the Hyperthermia Application
Authors: Boutros Nadia N. , Chen Ann D. , Gan Ryan N. , Gan Yong X.
Published: September 2018

The purpose of this work was to develop and analyze different materials that would be able to create the partially carbonized nanofibers through electrohydrodynamic casting followed by heat treatment. Test samples were created with different precursors containing polymer solutions and different added metal salts. After performing a series of steps to create each test sample, the sample was heat-treated to generate carbon nanofiber composites. The morphology of the carbon nanofiber composites was observed using a scanning electron microscope. Hyperthermia tests on typical fiber composites were performed.
Electrohydrodynamically Processed Poly-(Vinylidene Fluoride)/Polyaniline Composite Film on Soft Tissue Paper for Mechanoelectrical Energy Conversion and Vibration Sensing
Authors: Waliullah Muhammad S. , Gan Yong X. , Chen Ann D. , Gan Ryan N.
Published: September 2018

Electrohydrodynamic processing including electrospinning and electrospraying is suitable for depositing controllable structures in fiber or film form. In this work, the electrohydrodynamic approach was used to prepare poly(vinylidene fluoride)/polyaniline composite film. Scanning electron microscopic analysis was performed to show the morphology of the film on soft tissue paper. Self-poling of the film was found due to the high voltage application in the electrohydrodynamic process. The addition of polyaniline into PVDF improves the conductivity of the film significantly. Mechanoelectrical response of the film was demonstrated by measuring the open circuit voltage of the specimens under bending. The peak voltage generated is over 1.2 V due to the bending deformation of the film. The film has ultrafast response to the deformation. It is concluded that the film has multiple functions for mechanoelectrical energy conversion, vibration sensing, and structural integrity monitoring applications.
Finite Element Analysis and Simulation of Ultrasonic Powder Consolidation Process
Authors: James Sagil , Bhavsar Shripal
Published: September 2018

Ultrasonic welding is a solid-state joining process which uses ultrasonic vibration to join materials at relatively low temperatures. Ultrasonic powder consolidation is a derivative of the ultrasonic additive process which consolidates powder material into a dense solid block without melting. During ultrasonic powder consolidation process, metal powder under a compressive load is subjected to transverse ultrasonic vibrations resulting in a fully-dense consolidated product. While ultrasonic powder consolidation is employed in a wide variety of applications, the effect of critical process parameters on the bonding process of powder particles during consolidation is not clearly understood. This study uses a coupled thermo-mechanical finite element analysis technique to investigate the effect of critical process parameters including vibrational amplitude and base temperature on the stress, strain, and particle temperature distribution during the ultrasonic powder consolidation process. The study finds that during this process, the ultrasonically vibrating tool imparts cyclic vibratory shear stress on the particles. The simulation also revealed that the particle temperature just reaches the recrystallization point. Higher vibration amplitude imparted higher frictional heat on the particles, thereby aiding the consolidation process. The simulation study also showed indications of thermal softening and restricted grain boundary sliding during the ultrasonic powder consolidation process. The outcomes of this study can be used to further the industrial applications of ultrasonic powder consolidation process as well as other ultrasonic welding based processes.
Performance Testing of Endoscopic Biopsy Forceps
Authors: Linke Barbara S. , Toribio Anthony , Geary Shannon , Neumann Ulf P. , Roeth Anjali A.
Published: September 2018

Endoscopic biopsy forceps are the key to minimally invasive procedures to an endoscopic surgeon. These surgeons have to maneuver forceps with cutting performance through the body while maintaining minimal damage to the narrow channels during insertion. The amount of precision the user needs to successfully perform endoscopic surgery is high enough to create a preference amongst surgeons.

Physicians are often not involved in the purchasing decision on the instruments, but they usually can provide their preference of instrument mainly based on the subjective perception of how an instrument feels or works in their hands. To base discussions between surgeons and purchasing departments on quantitative data of forceps use performance, this study aims to provide a performance testing method for different instruments such as different brands, designs, reusable or single-use, or instruments in different wear stages. Ultimately, this will allow to determine which instrument performs with the maximum efficiency at the lowest cost.

First, findings in the literature on forceps failure, wear and testing are described. Then, the forceps design and handling during a biopsy are investigated. A preliminary test set-up is introduced for a repeatable biopsy test for endoscopic forceps. Different tissue types and samples can be used in the test stand to define an ideal acceleration profile for the forceps during biopsy and the cut can be analyzed by microscopy afterwards. A sensor on the operator’s wrist measures acceleration and jerk while pulling at the forceps, which will give new insight into the performance of different forceps types and forceps in different wear states, independent from forceps’ brand, design or wear states.
Thermally Assisted Self-Piercing Riveting of Aluminum AA6061-T6 to Ultra-High Strength Steels
Authors: Deng Lin , Lou Ming , Li YongBing , Carlson Blair E.
Published: September 2018

Self-piercing riveting has been widely used in vehicle body manufacturing to join aluminum alloys or aluminum to steel. However, it is difficult to rivet ultra-high strength steel (UHSS) because of its resistance to piercing of the rivet. In this paper, a thermally assisted self-piercing riveting (TA-SPR) process was proposed to improve riveting of the UHSS, through locally preheating the UHSS sheet using an induction coil prior to the traditional self-piercing riveting (SPR) process. An experimental system consisting of inductive heating apparatus, conventional self-piercing riveting equipment and coupon transfer mechanism was established and the steps, e.g., preheating, coupons transfer and riveting, were automatically conducted at preset schedules. Based on experiments with this system, the effects of heating current, heating time and coil heating distance on riveting of AA6061-T6 and DP980 were examined systematically by metallurgical analyses and mechanical tests. It was found that an appropriate combination of heating current and heating time, e.g., 0.5s at 600A, could produce crack-free joints having 77.8% higher undercut and 24% higher lap-shear strength, compared to results obtained using a conventional SPR process.
The Best and Worst Feed Directions in Milling Chatter
Authors: Wang J. J. Junz
Published: September 2018

In this paper, a 2D milling stability analysis is reduced to a 1D problem by performing a modal analysis on an oriented transfer function matrix under a given feed direction. The oriented frequency response function (FRF) of the oriented transfer matrix are obtained as explicit functions of the radial immersion and feed direction. At different feed directions in most of the lower immersion range, the process is demonstrated to be the least stable when the modal direction of the directional matrix is oriented at 45° and 225° and in the −45° and 135°, yielding a local minimum critical depth of cut, regardless of up or down cuts. At higher immersion, the worst critical depth of cut is dominated by the lower frequency mode, and becomes a constant, independent of the feed direction at full cut. When the modal direction is oriented along the x or y axes, the process has a local maximum critical depth of cut.
The Influence Factors and Prediction of Curve Surface Roughness in Micro-Milling Nickel-Based Superalloy
Authors: Lu Xiaohong , Wang Xinxin , Sun Jing , Zhang Hong , Feng Yixuan
Published: September 2018

Micro structure/parts during their useful life are significantly influenced by surface roughness quality. Machining of curve shapes is a necessity in micro-milling process. However, surface roughness in micro-milling curved surfaces is more complex, and few studies on the influence factors and prediction of the micro-milled curve surface roughness in micro-milling nickel-based superalloy have been done. The purpose of this paper is to study the effects of spindle speed, the radius of ball-end mill, axial cutting depth, and feed per tooth on the curved surface roughness in micro-milling Inconel 718 process based on single factor and orthogonal experiments. Utilizing the least square method, we build a surface roughness prediction model of micro-milled Inconel 718. Finally, experiments are conducted to verify the accuracy of the developed prediction model. The results indicate that the maximum relative error is 10.68%, and the mean relative error is 8.04%, which prove that the prediction model is correct. The work can provide a reference for selection of cutting parameters in micro-milling Inconel 718.
Design of Nano-Filled PET Sheets With Enhanced Barrier Properties
Authors: Quadrini Fabrizio , Bellisario Denise , Santo Loredana
Published: September 2018

Barrier properties are achieved in PET food packaging by using additives, coatings or multi-layers. An analytical model to predict the contamination during multiple recycling steps of this packaging is proposed. This model shows that lower contents of non-PET materials should be achieved to promote a valid recycling chain. A possible solution is using nano-technologies because of the very small amount of added material. Results are shown in the case of PVD coatings with aluminum target, and PET nano-composites. In both cases, less than 0.1 wt% of aluminum is able to reduce the oxygen transmission ratio of the PET packaging down to 50% of the virgin PET sheet.
Investigation of High-Speed Nanogrinding Mechanism Based on Molecular Dynamics
Authors: Liu Yao , Li Beizhi , Zheng Yihao
Published: September 2018

The SiC ceramic ductile grinding, which can obtain crack-free ground surface, is a challenge in brittle material machining. To understand the brittle material ductile grinding mechanism in the nanoscale, a molecular dynamics (MD) model is built to study the single diamond grit grinding silicon carbide ceramic. Through analyzing the MD simulation process, the grit forces the SiC to deform and form the chip through the plastic deformation and flow. The ground surface has no crack on the surface and damage layer thickness is less than one atom layer under the nanoscale depth of cut, which indicates the nanogrinding can achieve the pure ductile grinding for the SiC ceramic and obtain a crack-free and high-quality ground surface. Grinding force, stress, temperature, and specific energy increase with the wheel speed and depth of cut due to the higher grinding speed and a smaller depth of cut can generate a higher density of defects (vacancies, interstitial atoms, and dislocations) on the workpiece, which can make the silicon carbide ceramic more ductile. The high wheel speed is favorable for the ductile grinding.