bluuebunny/crossref_metadata_2025 huggingface dataset:
A Spectral Fiedler Field-based Contrast Platform for Imaging of Nanoparticles in Colon Tumor
Authors: Liu Chenang , Kapoor Ankur , VanOsdol Joshua , Ektate Kalyani , Kong Zhenyu , Ranjan Ashish
Published: July 2018

The temporal and spatial patterns of nanoparticle that ferry both imaging and therapeutic agent in solid tumors is significantly influenced by target tissue movement, low spatial resolution, and inability to accurately define regions of interest (ROI) at certain tissue depths. These combine to limit and define nanoparticle untreated regions in tumors. Utilizing graph and matrix theories, the objective of this project was to develop a novel spectral Fiedler field (SFF) based-computational technology for nanoparticle mapping in tumors. The novelty of SFF lies in the utilization of the changes in the tumor topology from baseline for contrast variation assessment. Data suggest that SFF can enhance the spatiotemporal contrast compared to conventional method by 2–3 folds in tumors. Additionally, the SFF contrast is readily translatable for assessment of tumor drug distribution. Thus, our SFF computational platform has the potential for integration into devices that allow contrast and drug delivery applications.
A Personalized Arrhythmia Monitoring Platform
Authors: Raj Sandeep , Ray Kailash Chandra
Published: July 2018

Arrhythmia detection is the core of cardiovascular disease diagnosis. Though, there is no such generic solution for detecting the arrhythmias at the moment they occur which is due to the non-stationary nature and inter-patient variations of ECG signals. The feature extraction and classification techniques are significant tools widely used in the automated classification of arrhythmias. This study aims to develop a personalized arrhythmia monitoring platform allowing real-time detection of arrhythmias from the subject’s electrocardiogram (ECG) signal for point-of-care usage. A novel method, i.e. discrete orthogonal stockwell transform (DOST) technique for feature extraction is employed to capture the significant time-frequency coefficients to constitute the feature set representing each of the ECG signals. These coefficients or features are classified using artificial bee colony (ABC) optimized twin least-square support vector machine (LSTSVM) for classifying the different categories of ECG signals. The ABC optimizes the dimension of the feature set and the learning parameters of the classifier. The proposed method is prototyped on the commercially available ARM-based embedded platform and validated on the benchmark MIT-BIH arrhythmia database. Further, the prototype is evaluated under two schemes, i.e. class and personalized schemes which reported a higher overall accuracy of 96.29% and 96.08% in the respective schemes than the existing works to the state-of-art CVDs diagnosis.
Xbra and Smad-1 cooperate to activate the transcription of neural repressor ventx1.1 in Xenopus embryos
Authors: Kumar Shiv , Umair Zobia , Yoon Jaeho , Lee Unjoo , Kim Sung Chan , Park Jae-Bong , Lee Jae-Yong , Kim Jaebong
Published: July 2018

Crosstalk of signaling pathways play crucial roles in cell proliferation, cell differentiation, and cell fate determination for development. In the case of ventx1.1 in Xenopus embryos, both BMP-4/Smad-1 and FGF/Xbra signaling induce the expression of neural repressor ventx1.1. However, the details of how these two pathways interact and lead to neural inhibition by ventx1.1 remain largely unknown. In the present study, Xbra directly bound to the ventx1.1 promoter region and inhibited neurogenesis in a Ventx1.1-dependent manner. Furthermore, Smad-1 and Xbra physically interacted and regulated ventx1.1 transcription in a synergistic fashion. Xbra and Smad-1 interaction cooperatively enhanced the binding of an interacting partner within the ventx1.1 promoter and maximum cooperation was achieved in presence of intact DNA binding sites for both Smad-1 and Xbra. Collectively, BMP-4/Smad-1 and FGF/Xbra signal crosstalk cooperate to activate the transcription of neural repressor ventx1.1 in Xenopus embryos. This suggests that the crosstalk between BMP-4 and FGF signaling negatively regulates early neurogenesis by synergistic activation of ventx1.1 in Xenopus embryos.
Interplay between human nucleolar GNL1 and RPS20 is critical to modulate cell proliferation
Authors: Krishnan Rehna , Boddapati Neelima , Mahalingam Sundarasamy
Published: July 2018

Human Guanine nucleotide binding protein like 1 (GNL1) belongs to HSR1_MMR1 subfamily of nucleolar GTPases. Here, we report for the first time that GNL1 promotes cell cycle and proliferation by inducing hyperphosphorylation of retinoblastoma protein. Using yeast two-hybrid screening, Ribosomal protein S20 (RPS20) was identified as a functional interacting partner of GNL1. Results from GST pull-down and co-immunoprecipitation assays confirmed that interaction between GNL1 and RPS20 was specific. Further, GNL1 induced cell proliferation was altered upon knockdown of RPS20 suggesting its critical role in GNL1 function. Interestingly, cell proliferation was significantly impaired upon expression of RPS20 interaction deficient GNL1 mutant suggest that GNL1 interaction with RPS20 is critical for cell growth. Finally, the inverse correlation of GNL1 and RPS20 expression in primary colon and gastric cancers with patient survival strengthen their critical importance during tumorigenesis. Collectively, our data provided evidence that cross-talk between GNL1 and RPS20 is critical to promote cell proliferation.
Repeated abortion in adulthood induces cognition impairment in aged mice
Authors: Wang Lili , Zhang Ying , Wang Haofeng , Li Hui , Zhao Ziying , Wang Ning , He Bin , Shi Cuige , Zhang Shucheng , Wang Jiedong
Published: July 2018

Age-related cognitive decline is one of the major aspects that impede successful aging in humans. Repeated abortion in adulthood can accelerate or aggravate cognitive deficiency during aging. Here we used repeated abortion in female mice adulthood and investigated the consequences of this treatment on cognitive performance during aging. We observed a substantial impairment of learning memory in 15 months old. This cognitive dysfunction was supported by Aβ elevation in CA region. Repeated abortion mice have uniform estrous cycles and decreased ERα expression in hypothalamus and hippocampus. Furthermore, repeated abortion not only significantly increased the HMGB1 expression in hippocampus but also increased the plasma and hippocampal protein levels of IL-1β, IL-6, and TNF-α. Finally, we identified that MPP-induced cell apoptosis and increased HMGB1 expression as well as IL-1β, IL-6, and TNF-α expression as following Aβ elevation. Taken together, our results identify possible molecular mechanisms underlying cognitive impairment during aging, and demonstrated the repeated abortion in adulthood on cognitive function in aged mice.
Concurrent guiding of light and heat by transformation optics and transformation thermodynamics via soft matter
Authors: Barros Wallysson K. P. , Pereira Erms
Published: July 2018

Controlling light and heat via metamaterials has presented interesting technological applications using transformation optics (TO) and transformation thermodynamics (TT). However, such devices are commonly mono-physics and mono-purpose, because the used metamaterial is designed to deal with one type of physical mechanisms. Here we demonstrate, for the first time, how to connect TO and TT via the liquid crystal 4-Cyano-4’-pentylbiphenyl (5CB) and, to exemplify such link, we present a multiphysics, multi-purpose device that simultaneously controls light and heat using such material. The anisotropic multiphysics properties of 5CB bond TO and TT, expanding the usage of these theories. The device, composed by 5CB confined between two right circular concentric cylinders, concentrates light (as a converging lens) and simultaneously repels heat from the inner cylinder when the molecules are along the direction$$\hat{{\boldsymbol{\rho }}}$$ρˆand it disperses light (as a diverging lens) and concurrently concentrates heat to the inner cylinder, without disturbing the external temperature field, when the molecules are along the direction$$\hat{{\boldsymbol{\theta }}}$$θˆ, contributing for saving materials and designing miniaturized multiphysics systems.
GRK2 knockdown in mice exacerbates kidney injury and alters renal mechanisms of blood pressure regulation
Authors: Tutunea-Fatan Elena , Abd-Elrahman Khaled S. , Thibodeau Jean-Francois , Holterman Chet E. , Holleran Brian J. , Leduc Richard , Kennedy Christopher R. J. , Gros Robert , Ferguson Stephen S. G.
Published: July 2018

The renin-angiotensin system regulates blood pressure and fluid balance in the body primarily via angiotensin receptor 1 (AT1R). Renal AT1R was found to be primarily responsible for Ang II-mediated hypertension. G protein-coupled receptor kinase 2 (GRK2) modulates AT1R desensitization and increased GRK2 protein expression is reported in hypertensive patients. However, the consequences of GRK2 inhibition on kidney functions remain unknown. We employed shGRK2 knockdown mice (shGRK2 mice) to test the role of GRK2 in kidney development and function that can be ultimately linked to the hypertensive phenotype detected in shGRK2 mice. GRK2 knockdown reduced kidney size, nephrogenesis and glomerular count, and impaired glomerular filtration. Glomerular damage in adult shGRK2 mice was associated with increased renin- and AT1R-mediated production of reactive oxygen species. The AT1R blocker, Losartan, normalized elevated blood pressure and markedly improved glomerular filtration in the shGRK2 knockdown mice. Our findings provide evidence for the crucial role of GRK2 in renal regulation of blood pressure. It also suggests that the detrimental outcomes of GRK2 inhibitors on the kidney should be carefully examined when used as antihypertensive.
Continuous applications of biochar to rice: Effects on nitrogen uptake and utilization
Authors: Huang Min , Fan Long , Chen Jiana , Jiang Ligeng , Zou Yingbin
Published: July 2018

Improving soil quality is critical for increasing rice yield, and biochar could be a beneficial soil amendment for high yield. This study was conducted to determine the effects of continuous (repeated seasonal) applications of biochar on nitrogen (N) uptake and utilization in rice. A fixed field experiment was done in Yongan Town, Hunan Province, China, in six continuous seasons (the early and late rice-growing seasons from 2015 to 2017). Results showed that biochar application did not significantly affect soil N uptake in the first four seasons. The effect of biochar application on fertilizer N uptake was not significant in three of the first four seasons. In the fifth and sixth seasons, biochar application resulted in 14–26% increases in soil N uptake but 19–26% decreases in fertilizer N uptake. Soil N availability did not explain the increased soil N uptake with biochar application. The decreased fertilizer N uptake with biochar application was attributed to both decreased fertilizer N availability and increased N loss through ammonia volatilization. As a consequence of a compensation between the increased soil N uptake and the decreased fertilizer N uptake, the effect of biochar application on total N uptake was not significant in the fifth and sixth seasons. However, biochar application led to 7–11% increases in internal N use efficiency in the fifth and sixth seasons and 6% increase in grain yield in the sixth season. Our study suggests that the effects of repeated seasonal applications of biochar on N uptake and utilization in rice depend on the duration of biochar application. Longer continuous applications of biochar can increase internal N use efficiency and grain yield in rice with insignificant change in total N uptake.
Intracellular membranes of bacterial endospores are reservoirs for spore core membrane expansion during spore germination
Authors: Laue Michael , Han Hong-Mei , Dittmann Christin , Setlow Peter
Published: July 2018

Bacterial endospores are formed by certain bacteria, such as Bacillus subtilis or the pathogenic Bacillus anthracis and Clostridioides difficile, to allow survival in environmental conditions which are lethal to vegetative bacteria. The spores possess a particular architecture and molecular inventory which endow them with a remarkable resistance against desiccation, heat and radiation. Another remarkable spore feature is their rapid return to vegetative growth during spore germination and outgrowth. The underlying processes of this latter physiological and morphological transformation involve a number of different events, some of which are mechanistically not entirely understood. One of these events is the expansion of the central spore core, which contains the DNA, RNA and most spore enzymes. To date, it has been unclear how the ~1.3- to 1.6-fold expansion of the core membrane surface area that accompanies core expansion takes place, since this occurs in the absence of significant if any ATP synthesis. In the current work, we demonstrate the presence of intracellular membrane structures in spores located just below the core membrane. During spore germination these internal core membranes disappear when the core size increases, suggesting that they are integrated into the core membrane to allow core expansion. These intracellular membranes are most probably present as more or less compressed vesicles or tubules within the dormant spore core. Investigations of spores from different species suggest that these intracellular membrane structures below the core membrane are a general feature of endospore forming bacteria.
MANTA2, update of the Mongo database for the analysis of transcription factor binding site alterations
Authors: Fornes Oriol , Gheorghe Marius , Richmond Phillip A. , Arenillas David J. , Wasserman Wyeth W. , Mathelier Anthony
Published: July 2018

Interpreting the functional impact of noncoding variants is an ongoing challenge in the field of genome analysis. With most noncoding variants associated with complex traits and disease residing in regulatory regions, altered transcription factor (TF) binding has been proposed as a mechanism of action. It is therefore imperative to develop methods that predict the impact of noncoding variants at TF binding sites (TFBSs). Here, we describe the update of our MANTA database that stores: 1) TFBS predictions in the human genome, and 2) the potential impact on TF binding for all possible single nucleotide variants (SNVs) at these TFBSs. TFBSs were predicted by combining experimental ChIP-seq data from ReMap and computational position weight matrices (PWMs) derived from JASPAR. Impact of SNVs at these TFBSs was assessed by means of PWM scores computed on the alternate alleles. The updated database, MANTA2, provides the scientific community with a critical map of TFBSs and SNV impact scores to improve the interpretation of noncoding variants in the human genome.
Erratum: Human grasping database for activities of daily living with depth, color and kinematic data streams
Authors: Saudabayev Artur , Rysbek Zhanibek , Khassenova Raykhan , Varol Huseyin Atakan
Published: July 2018

Scientific Data 5:180101 doi: 10.1038/sdata.2018.101 (2018), Published 29 May 2018; Updated 24 July 2018 An incorrect URL was erroneously included in Data Citation 1. The correct URL has now been inserted into the HTML and PDF versions.
Microarray data of transcriptome shifts in blood cell subsets during S1P receptor modulator therapy
Authors: Koczan Dirk , Fitzner Brit , Zettl Uwe Klaus , Hecker Michael
Published: July 2018

Treatment with fingolimod, a sphingosine-1-phosphate (S1P) receptor modulator, prevents the egress of immune cell subpopulations from lymphoid tissues into the blood. We obtained peripheral blood samples from patients with relapsing multiple sclerosis before the initiation of fingolimod therapy, after one day and after 3 months. To investigate the differential expression induced by the drug, five different cell populations were isolated. We then employed 150 Human Transcriptome Arrays (HTA 2.0) interrogating >245,000 protein-coding and >40,000 non-coding transcript isoforms. After 3 months of treatment, CD4+ and CD8+ T-cells showed huge transcriptome shifts, whereas the profiles of B-cells (CD19+) were slightly altered and those of monocytes (CD14+) and natural killer cells (CD56+) remained unaffected. With >6 million probes for exons and splice junctions, our large HTA 2.0 dataset provides a deep view into alternative splicing patterns in immune cell subsets. Our data may also be useful for comparing the effects on gene expression signatures of novel S1P receptor modulators, which are currently tested in clinical trials for other autoimmune and neurodegenerative diseases.
Development of an adaptable headspace sampling method for metabolic profiling of the fungal volatome
Authors: Ahmed Waqar M. , Geranios Pavlos , White Iain R. , Lawal Oluwasola , Nijsen Tamara M. , Bromley Michael J. , Goodacre Royston , Read Nick D. , Fowler Stephen J.
Published: July 2018

Culture headspace sampling and analysis of aspergillus fumigatus volatile metabolites by TD-GC-MS.
The open d-shell enforces the active space in 3d metal catalysis: highly enantioselective chromium(ii) pincer catalysed hydrosilylation of ketones
Authors: Schiwek Christian H. , Vasilenko Vladislav , Wadepohl Hubert , Gade Lutz H.
Published: July 2018

A square-planar chromium precatalyst with its active space shaped by the metal centre was employed in an unprecedented enantioselective hydrosilylation of ketones.
Local structural changes in graphene oxide layers induced by silver nanoparticles
Authors: Pienpinijtham Prompong , Vantasin Sanpon , Wong-u-ra Oraporn , Kitahama Yasutaka , Ekgasit Sanong , Ozaki Yukihiro
Published: July 2018

Local structural changes of graphene oxide (GO) in silver/graphene oxide (AGO) nanocomposites were successfully investigated using tip-enhanced Raman scattering (TERS).
Understanding the influence of carrageenan oligosaccharides and xylooligosaccharides on ice-crystal growth in peeled shrimp (Litopenaeus vannamei) during frozen storage
Authors: Zhang Bin , Zhang Xiao-li , Shen Chun-lei , Deng Shang-gui
Published: July 2018

Cryoprotective saccharides are widely accepted antifreeze additives that reduce thawing loss, maintain texture, and retard protein denaturation in frozen seafood.
trans-Chalcone prevents insulin resistance and hepatic inflammation and also promotes hepatic cholesterol efflux in high-fat diet-fed rats: modulation of miR-34a-, miR-451-, and miR-33a-related pathways
Authors: Karimi-Sales Elham , Jeddi Sajad , Ebrahimi-Kalan Abbas , Alipour Mohammad Reza
Published: July 2018

trans-Chalcone significantly inhibits high-fat diet-induced dysregulation of miR-34a-, miR-451-, and miR-33a-related pathways in the liver of rats.
High carrier mobility in monolayer CVD-grown MoS2 through phonon suppression
Authors: Huo Nengjie , Yang Yujue , Wu Yu-Ning , Zhang Xiao-Guang , Pantelides Sokrates T. , Konstantatos Gerasimos
Published: July 2018

The electron–phonon scattering has been much suppressed in CVD MoS2, leading to high carrier mobility improvement up to 60 cm2 V−1 s−1.
Promoting intracellular delivery of sub-25 nm nanoparticlesviadefined levels of compression
Authors: Yang Hongrong , Yao Yifei , Li Huize , Ho Lok Wai Cola , Yin Bohan , Yung Wing-Yin , Leung Ken Cham-Fai , Mak Arthur Fuk-Tat , Choi Chung Hang Jonathan
Published: July 2018

An experimental set-up for evaluating the cellular uptake of sub-25 nm nanoparticles under defined levels of uniaxial compression is presented.
Antibody–nucleotide conjugate as a substrate for DNA polymerases
Authors: Balintová J. , Welter M. , Marx A.
Published: July 2018

Antibody-modified nucleotides are developed and their incorporation into nascent DNA by DNA polymerases exploited for the development of the naked-eye detection of DNA.
Facile synthesis of 2D nitrogen-containing porous carbon nanosheets induced by graphene oxide for high-performance supercapacitors
Authors: Zhang Xu , Fan Qiuyu , Zhao Yingyuan , Wang Man , Meng Yulan , Xiao Yonghou , Lei Xiaoting , Yang Juan
Published: July 2018

2D N-containing porous carbon nanosheets are prepared in the presence of GO as a structure-directing agent by a facile hydrothermal method.
Binary Ni2FeOx anchored on modified graphite for efficient and durable oxygen evolution electrocatalysis
Authors: Bai Lu , Guan Jingqi
Published: July 2018

Ni2FeOx@G-Ph-SN demonstrates superior electrochemical water oxidation activity (only 265 mV overpotential at 10 mA cm−2) and outstanding stability in 1.0 M KOH.
Atomic insight into the structural transformation and anionic/cationic redox reactions of VS2 nanosheets in sodium-ion batteries
Authors: Wang Dashuai , Zhao Yingying , Lian Ruqian , Yang Di , Zhang Dong , Meng Xing , Liu Yanhui , Wei Yingjin , Chen Gang
Published: July 2018

The mechanisms for phase transitions, charge-transfer reactions, and ionic diffusion kinetics during Na+ insertion in VS2 nanosheets were systematically investigated via experimental testing and first principles calculations.
3D cellular CoS1.097/nitrogen doped graphene foam: a durable and self-supported bifunctional electrode for overall water splitting
Authors: Liang Hui , Jiang Degang , Wei Shuang , Cao Xueying , Chen Tao , Huo Bingbing , Peng Zhi , Li Chenwei , Liu Jingquan
Published: July 2018

3D cellular N-doped graphene foam supported CoS1.097 nanoparticles as highly active and stable bifunctional catalysts for overall water splitting.
N-Alkylcarbazoles: homolog manipulating long-lived room-temperature phosphorescence
Authors: Zhang Zhenzhen , Tang Liangliang , Fan Xiaojing , Wang Yanhui , Zhang Kai , Sun Qikun , Zhang Haichang , Xue Shanfeng , Yang Wenjun
Published: July 2018

The homolog effect was demonstrated to be a promising avenue to manipulate the RTP of organic luminophores.
Formation of hot subdwarf B stars with neutron star components
Authors: Wu You , Chen Xuefei , Li Zhenwei , Han Zhanwen
Published: July 2018

Context. Binary population synthesis predicts the existence of subdwarf B stars (sdBs) with neutron star (NS) or black hole (BH) companions. Several works have been dedicated to finding such systems, but none has been confirmed yet. Theoretically, the formation of sdBs with white dwarf (WD) and main sequence (MS) companions has been well investigated, while those with NS or BH companions remain to be explored further.

Aims. We systematically investigate the formation of sdB+NS binaries from binary evolution and aim to obtain some clues for a search for such systems.

Methods. We started from a series of MS+NS systems and determined the parameter spaces for producing sdB+NS binaries from the stable Roche-lobe overflow (RLOF) channel and from the common envelope (CE) ejection channel. The parameters for sdB+NS binaries were obtained from detailed binary evolution calculation with the code called modules for experiments in stellar astrophysics (MESA), and the CE parameters were given by the standard energy budget for CE evolution. The MS star had an initial mass ranging from 0.8 to 5 M⊙. Various NS accretion efficiencies and NS masses were examined to investigate the effects they have. We show the characteristics of the produced sdB+NS systems, such as the mass of components, orbital period, the semi-amplitude of the radial velocity (K), and the spin of the NS component.

Results. sdB+NS binaries can be produced either from stable RLOF or from CE ejection. In the stable RLOF channel, sdBs can be formed when the donor starts mass transfer close to the tip of the giant branch if the donor has an initial mass ≤2.0 M⊙. For more massive donors, sdBs can be formed when the donor starts mass transfer during the Hertzsprung gap or near the end of the MS. The orbital period of sdB+NS binaries produced in this way ranges from several days to more than 1000 days and moves toward the short-period (∼hr) side with increasing initial MS mass. The highest K is about 150 km s−1 for an MS star of initially 5 M⊙. However, the sdB+NS systems that result from CE ejection have very short orbital periods and then high values of K (up to 800 km s−1). Such systems are born in very young populations (younger than 0.3 Gyr) and are potential gravitational wave sources that might be resolved by the Laser Interferometer Space Antenna (LISA) in the future. Gravitational wave radiation may again bring them into contact on a timescale of only ∼Myr. As a consequence, they are rare and hard to discover. The pulsar signal is likely a feature of sdB+NS systems caused by stable RLOF, and some NS components in sdB binaries may be millisecond pulsars. Various NS accretion efficiencies and NS masses change some properties of sdB+NS binaries, but not our general results.
Nanofluid Al2O3–H2O evaporation: energy and deposition patterns
Authors: Li Tianying , Liu Bin , Ma Xiaoyan , Bennacer Rachid
Published: July 2018

This study experimentally investigated the deposition patterns of Al2O3–H2O nanofluid droplets with mass concentration of 0.05%, 0.2%, 1% and 3% after evaporating on transparent glass substrate with temperature of 30 °C, 40 °C, 50 °C and 60 °C, obtaining three typical kinds of patterns: the peripheral ring, the thin uniform layer with a thicker ring at the periphery and the concentric circular respectively. With the increase of concentration, the uniform pattern embedded in the peripheral ring changes into a concentric circular pattern gradually. The flow velocities corresponding to the three typical forces were solved and the results are 10−3 < Vma/Vrad − a < 10−2 and 10−28 < VDLVO+/Vrad − a < 10−5 (Marangoni, Vma, the integral mean value of the entire radius Vrad − a and the velocity caused by DLVO force VDLDO+). This indicated that the radial flow played a dominant role in the formation of the deposition pattern.
Lateral transport of traffic pollutants in complex urban area
Authors: Kluková Zuzana , Nosek Štěpán , Jaňour Zbyněk , Kukačka Libor
Published: July 2018

Owing to the spatial variability of an urban area, even the transport of passive scalar is complex. The examination of the pollutant transport in such turbulent flow as occur within the urban canopy requires the measurements not only the advective but also the turbulent part of this transport. However, recent measurement techniques for the turbulent transport have their limitations. In particular, these measurements are very demanding if one needs to analyze the ventilation processes of the street through the entire streetcanyon openings and which needs to be performed also in the positions where the handling with the measurement instruments might comprise a complex issue or is even impossible. Thus we present a comparison of two methods for the assessment of turbulent and advective pollution fluxes through the lateral openings of two different street canyons with respect to the wind direction and the roof-height nonuniformity to evaluate the importance of the measurement of these fluxes nearby the street-canyon walls. Both of them are based on the simultaneous point measurement of concentration and lateral velocity component and the interpolation between the last measured point and the street-canyon borders, but in the second method the measured area is extended from 77% to 84% of the total area of the lateral openings.
Detached chip smoothing during involute gear slotting in relation to generated tooth features
Authors: Bordeanu Mihai , Frumuşanu Gabriel , Oancea Nicolae
Published: July 2018

The problematic concerning the generating process uniformity, in the specific case of machining involute gear teeth with a rack shaped cutter provided by a single tooth is one of the notable challenges from gear teeth machining domain. In previous work, it has already been presented a solution of this problem, based on a graphical application in CATIA. The solution involves the modification of enveloping process ongoing, such as the circular feed motion takes place with variable speed. The variation law of feed motion speed that should be followed for smoothing the detached chip area is, obviously, different for each gear-type specific case. This paper is aiming to study the influence of generated tooth features onto this law form. Graphical and numerical applications addressing different cases of teeth numbers for the generated gear are presented and analyzed.
Study of an algorithm regarding production scheduling for injection mold manufacturing
Authors: Pralea Bogdan , Nagîţ Gheorghe
Published: July 2018

The objective of this study is to establish an algorithm for estimating the time necessary to manufacture an injection mold. The idea is based on the fact that one of the most crucial activities for a successful business is to correctly define the time and also cost of the product’s machining hours. It will sum up various variable based on gathered data. The variable will be focused around the quantity of material manufactured during a certain period of time. This algorithm will empower the designer to give a more precise evaluation of hours and cost in shorter period of time based on the mold 3D model.
Using artificial neural network models for the prediction of thrust force and torque in drilling operation of Al7075
Authors: Kyratsis Panagiotis , Efkolidis Nikolaos , Ghiculescu Daniel , Kakoulis Konstantinos
Published: July 2018

This study investigates the thrust force (Fz) and torque (Mz) in a drilling process of an Al7075 workpiece using solid carbide tools (Kennametal KC7325), depending on the effects of crucial cutting parameters such as cutting velocity, feed rate and tool diameter of 10mm, 12mm and 14mm. Artificial neural networks (ANN) methodology is used in order to acquire mathematical models for both the thrust force (Fz) and torque (Mz) related to the drilling process. The ANN results showed that the best prediction topology of the network for the thrust force was the one with five neurons in the hidden layer, while for the case of Mz the best network topology for the prediction of the experimental values was the one with six neurons in the hidden layer. Based on the results acquired, the ANN models achieved accuracy of 1,96% and 1,95% for both the thrust force and torque measured, while the R coefficient for the prediction model of the thrust force is 0.99976 and 00.99981 for the torque. As a result they can be considered as very accurate and appropriate for their prediction.
Reamers cutting edge preparation for improvement the GGG 40 machining
Authors: Voina Ioan-Doru , Sattel Stefan , Contiu Glad , Faur Adrian , Luca Bogdan
Published: July 2018

The improvement of the microgeometry became a subject of a great interest in cutting tools optimization. This paper approaches the process of cutting edge preparation of solid carbide reamers. It has been analyzed the evolution of cutting edge wear resistance in the material GGG 40 using the scanning electron microscope (SEM). The work also compared the rounded cutting edge reamers realized using wet abrasive jet machining with standard unprepared cutting edge. To obtain different microgeometries were experienced a number of machining strategies, which resulted in four combinations of roundness and forms for the cutting edge. In order to validate the results, the author studied the wear resistance during the reaming tests, the influence of prepared surface of the cutting edge on metallic coating layer adhesion. The final purpose was to determinate the optimal strategy of cutting edge preparation considering the evolution of wear during the reaming process.
Design and manufacturing of a fixing device for incremental sheet forming process
Authors: Nasulea Daniel , Oancea Gheorghe
Published: July 2018

In incremental sheet forming processes, the expensive dedicated tool are avoided and replaced with a cheap and simple fixing device which support the sheet metal blanks. The current paper presents how a fixing device used for single point incremental forming device is designed, FEM simulated and manufactured. The fixing device can be used for parts with a cone frustum and pyramidal frustum made of DC05 deep drawing steel. The forces developed in the process and the device displacements were estimated using FEM simulation. The device components were manufactured using a CNC machines and the physical assembly is also presented in the paper.
Evaluation of the supporting plate edge radius and position effects on springback in incremental forming, part A
Authors: Abass Khalil Ibrahim
Published: July 2018

Incremental Forming IF is a suitable technique for producing complex forms. The geometry of product is quite free; on the other hand, there are limitations regarding the sheet thickness and the tools used. The material formability is affected by the product profile requirements, and the straightening of product wall is affected by the tool path. Also, the wall angle is one of most important characteristics that are limited by the sheet profile thickness. The geometry of the product determines the type of supporting tool and its complexity. The horizontal surface can be produced without supporting tool, but will result inclined. Without supporting tool, the sheet tends to bend as an alternative of stretching and the surface becomes wavy. For the present study, Aluminum (A1025) alloy sheets are used to deform a product using a supporting plate (with radius). The supporting plate is used to analyze the effect of springback during the process and for better control over the material flow. The study aims to understand the distribution of strain at the deformed part section for each step size. Also, the primary reasons for the product failure by springback and the final products have been evaluated and analyzed in details.
Research on 3D printed fixture components
Authors: Chitariu Dragoş-Florin , Munteanu Adriana
Published: July 2018

Fixtures are used for orientation, positioning and tightening of the workpiece during machining, control and assembly. The main fixture requirements are: orientation, positioning and tightening precision in accordance with the machining requirements. The materials used for fixture components, especially, supports and clamping mechanism are, usually, alloy steel with HRC hardness up to 55-60 HRC. These components are machined to high level of precision thus assuring the overall precision of the fixture. In order to achieve high stiffness and a good dampening capacity the fixture become, usually, very heavy. In the case of manually operated fixtures light weight is an advantage; also there are operations such as inspection, assembly where the operating forces are low. In this case lightweight materials can be used for fixture construction. In this paper the FDM (Fused Deposition Modeling) 3D printing technology is used. Support buttons and v-block fixture components were selected and 3D printed. The effect of printing orientation of active surfaces of support was analysed. The dimensional accuracy and surface roughness on the active surface were measured. Experimental results indicate that surface roughness is dependent on the orientation of the printed workpiece.
Finite element simulation and experimental investigation of cold forward extrusion process
Authors: Luca Dorin
Published: July 2018

Extrusion is the plastic deformation process that allows for the highest degree of complexity profiles to be obtained. This paper presents the simulation of a cold forward extrusion process using the finite element method. The results obtained show the stresses, strains and temperatures during the plastic deformation of the material, as well as the stresses and strains in the punch and die. The analysis of the results obtained for different geometric dimensions of the working tools allowed the optimization of the studied extrusion process. In order to validate the finite element model, experiments were carried out with the data acquisition from the real process, which allowed the appreciation that numerical and experimental data are found in a good agreement.
Supporting plate edge radius and internal hole diameter relation effect on the springback in incremental forming, part B
Authors: Abass Khalil Ibrahim
Published: July 2018

Incremental Forming, IF technology is a method for producing complex 3D-dimensional sheet profiles. Compared to conventional forming process, IF has some advantages, such as the punch-die set product deformation is not necessary, lower tools cost, shorter time prototype production, flexibility. The accuracy of the incremental forming products is still lower than those produced by the conventional forming process. One of the main parts of the IF tools-set is the supporting tools. The product profile accuracy limits the simplicity or complexity of the supporting tools. When the product profile does not contain a horizontal surface, the simple supporting tool can be used. If the product profile is more complex, the supporting tools should include more details. The present work introduces the effect of supporting plate radiuses in SPIF, Single Point Incremental Forming process. The supporting plate is used to investigate the effect of springback during the forming process. Aluminum sheet metals (A1025) are used for manufacturing the products. The study objective is to understand the springback behavior, which is affected by supporting tools. The strain distributions of the final deformed product section at each step size have been analyzed and evaluated in detail.
Device for the study of sharp peaks behavior under the action of single electrical discharges
Authors: Eţcu Mihaela , Slătineanu Laurenţiu , Croitoriu Sebastian-Nicolae
Published: July 2018

Currently, the electrical discharge machining is mainly applied to obtain surfaces difficult to be obtained using other machining processes in the workpieces made of electroconductive materials. The electroerosion process involves the initiation of electrical discharges in the zones where there is the lowest electrical resistance between the tool electrode and the workpiece. The study of the asperities peaks behavior under the action of the electric discharges would allow a better understanding of gradual developing of the surfaces generated by the electroerosive process. A way of addressing this problem could be based on the use of a device that would allow the study of the influence exerted by some process input factors on the results of a single electrical discharge developed between the test piece sharp peak and the tool electrode. The formulation of the functional requirements and the application of some methods of stimulating the technical creativity and of selecting solutions on the basis of predetermined criteria allowed the definition of a principle solution corresponding to an experimental device applicable for studying the behavior of sharp peaks under the action of single electrical discharges.
Characterisation of porous coatings formed on titanium under AC plasma electrolytic oxidation
Authors: Rokosz Krzysztof , Hryniewicz Tadeusz , Gaiaschi Sofia , Chapon Patrick , Raaen Steinar , Dudek Łukasz , Pietrzak Kornel , Malorny Winfried , Ciuperca Radion
Published: July 2018

The Plasma Electrolytic Oxidation (PEO) process may be used to fabricate porous coatings on titanium. The ranges of voltages used in case of these plasma treatments are different. It has been found that for DC PEO processing the voltage must be higher than that in the case of AC PEO treatment. In addition, the shape and frequency of the voltage signal have also an influence. In the paper scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy and glow discharge optical emission spectroscopy (GDEOS) were used to characterise obtained coatings. It was found that it is possible to obtain the porous coatings enriched with phosphorus and copper by use of AC-PEO at only 200 Vpp, while increasing the PEO voltage results in non-porous and cracked coatings. Based on GDEOS for 200 Vpp three sublayers were used, with ranges of 0-400, and 400-2400, and 2400-3600 seconds of sputtering time for first, and second, and transition sublayers respectively. XPS spectra for sample processed at 200 Vpp indicate in top 10 nm layer presence of titanium as Ti4+ and phosphorous as phosphates (most likely PO43–, HPO42–, H2PO4–, P2O73–).
Considerations regarding the use of cryogenic cooling in metal cutting as an alternative to conventional cooling – brief review
Authors: Bocăneţ Ana Maria , Croitoru Cristian
Published: July 2018

This paper presents a study regarding the latest researches on cryogenic cooling used in metal cutting as an opportunity for achieving green manufacturing, in terms of cryogenic methods, cutting tools, effects on cutting process parameters, industrial solutions and some possible applications in the areas where this cooling method presents deficiencies.
The study of the screen printing quality depending on the surface to be printed
Authors: Cazac Viorica , Cîrja Jana , Balan Emilia , Mohora Cristina
Published: July 2018

This paper presents the study results regarding the analysis of the screen printing quality on different types of materials. The quality of the screen printing is determined by several particularities of the screen printing process such as: the type of mesh, screen ruling, ink viscosity, raster spacing, etc. The material which is supposed to be printed is as important as the particularities of the screen printing process itself. The composition, structure and features of the printed items as well as the composition, viscosity and other ink properties, all together determine the quality of the screen printed matter.
Investigation of the geometric change of plastic articles made by polyamide
Authors: Aclan Metin , Oezden Rauf , Danho Saliba
Published: July 2018

The following paper includes an investigation of the geometric variation of plastic workpieces in a simulated environment of normal climate by 21° / 50% relative humidity. In the industrial manufacturing, the daily quality checks are required to determine, if the plastic workpieces can be released. Due to the humidity or water absorption, the plastic workpiece grows so far that the dimensional accuracy is not given. In this investigation, the results of 12 weeks are determined and presented.
Finite element analysis of the stress distribution in a representative elementary volume of mineral casting
Authors: Ciupan Mihai
Published: July 2018

Mineral casting is a type of polymer concrete that has started to be used in commercial machine-tools in the last few years because of its low cost of manufacturing and vibration damping capabilities. The paper presents the modelling and finite element analysis of a representative elementary volume (REV) made of mineral casting subjected to tensile loading. The aim of the paper is to assess the stress distribution that develops inside the specimen in order to understand and improve the material.
Experimental evaluation of Ellis scale for assessment of product's industrial design
Authors: Dumitrescu Andrei , Purcărea Mihail
Published: July 2018

The product development team has the task, amongst many others, to conceive the product's industrial design. Because it was proven and acknowledged that product's industrial design plays an important role in its success in the marketplace, the proposed design has to be evaluated based on an objective method. S.R. Ellis has proposed a method with seven criteria. The method was used by some researchers, but it has never been properly evaluated by an independent party. This paper presents the results of a scientific experiment aimed to test Ellis' method.
A systematic procedure to obtain the block diagram model from the bond graph model
Authors: Ibănescu Radu , Ibănescu Mihaela
Published: July 2018

The bond-graph method for the analysis of systems dynamics is very widespread in engineering and, because of its simplicity and its advantages, it has been developed a lot in the last decades. The bond graph model is a diagram which describes the manner of transmitting and transforming the power in a system, starting from the source up to the final elements. One of the most preferred ways of using the bond-graph diagram is the construction of the block diagram, appropriate for an adequate soft, the most frequently used one being MATLAB-SIMULINK. The block diagram model has a wide range of application in the study of systems dynamics because of its great advantages in case of numerical simulations. The manner of obtaining the block diagram from the bond-graph diagram is left at researcher choice, because there are no clear and well-defined procedures. The work presents a systematic procedure which contains several well-defined steps that lead to an exact and unitary approach of this problem.
An integrated engineering solution used for enhancing the design of a technological device for automated assembly
Authors: Pista Ionut Madalin , Merticaru Vasile , Ripanu Marius Ionut
Published: July 2018

The paper presents a theoretical approach and a case study upon the use of an advanced CAD solution integrated with another engineering design software solution embedding DFMA concepts, particularly applied within the product and manufacturing process design for technological devices. The main objective of implementing CAD and DfX/DFMA integrated solutions is to guide designers into the product development phase so that a better design can be achieved in a shorter time and with lower costs. The case study analyzes an assembly model developed for an indexing mounting table dedicated for the automated assembling of an industrial electrical plug inlet. The assembly product model has been developed using 3D parametric modeling specific tools, further on it has been subjected to analysis based on DFMA principles and after that its components have been redesigned to respond to the analysis results. Some of the case study results and their interpretation are discussed in the paper content and finally some overall conclusions are included along with some intended future research directions.
Solution to optimize the NC programs for milling machining applications
Authors: But Adrian , Botnari Vlad
Published: July 2018

The paper present solutions to optimize the NC program. Using the original NC program, keep the technology with the same cutting tools, the results give us less time of manufacturing with more protection to collisions. The use of new softer with real capabilities solution to manage and optimize the CNC technologies.
Multi-criteria analysis of wearable activityfitness trackers and 3D concept models of smart jewellery
Authors: Marinescu (Repanovici) Raluca
Published: July 2018

The technological development of wearable activity tracking devices with a whole range of functions is considered in this paper. Experts from different decision-making groups performed the multiple attribute evaluation of three devices for heart rate, exercise and sleep monitoring: a watch, a bracelet and a ring. MCA is applied to determine the relative weights of evaluation criteria. The result shows that the ring is the most suitable tracker that fits seamlessly into everyday life. Following the result, several 3D models of smart jewellery are presented for rapid prototyping.
About the influence of wheel-rail adhesion on the maximum speed of trains
Authors: Spiroiu Marius-Adrian
Published: July 2018

Wheel-rail adhesion is a fundamental aspect in rail transport, with high impact on traction and braking of trains. In the case of high speeds trains, wheel-rail adhesion is particularly important, as the maximum usable traction force is limited by the adhesion force. The present paper analyses the influence of wheel-rail adhesion on the maximum speed of trains, considering ranges of usual values for the track gradient and the adhesion coefficient and the real data of two Japanese high-speed trains. Analysis shows that low adhesion and high track gradient result in significant reduction of train speed.