bluuebunny/crossref_metadata_2025 huggingface dataset:
Savings operations with random commencement and conclusion
Authors: Valls Martínez María del Carmen , Cruz Rambaud Salvador , Abad Segura Emilio
Published: November 2019

Purpose

The progressive aging of the population is suggesting that public pension plans should be increasingly supplemented by private savings schemes. Accordingly, this supposes the appearance of a wide range of innovative savings products to meet the varying needs of savers and financial institutions. In practice, most contracted savings operations are nonrandom, that is to say, all amounts involved in the transaction are sure as well as their respective maturities. Consequently, the purpose of this paper is to propose a savings operation which includes the randomness derived from the contingencies which suppose the eventual but unpredictable death of the saver and a person designated by him to receive the final agreed amount.

Design/methodology/approach

The methodology used in this paper is financial mathematics where the risk has been introduced as an element which defines the main characteristics of this novel saving operation.

Findings

The proposed model extends the range of savings products by describing an actual innovation with new practical applications with respect to the traditional models of saving. In this paper, the authors have proposed a new type of saving based on the contingency derived from the life expectancy of the saver, by raising an operation in which the commencement and conclusion of the savings period are random. These savings operations represent, undoubtedly, a novelty from a financial point of view.

Originality/value

The main added value of this paper is that these contingencies affect the periodic deposits in each period from the first to the last maturities of installments. Moreover, the different parameters of such random transactions are defined.
Dynamics of credit decision-making: a taxonomy and a typological matrix
Authors: Saliya Candauda Arachchige
Published: November 2019

Purpose

The purpose of this paper is to broaden understanding as to how certain social/personal dynamics influence credit decisions in Sri Lanka, elucidating them through a taxonomy and a conceptual typological matrix.

Design/methodology/approach

This research is an exploratory case study. The primary data collection methods are interviews and reconstruction of experiences. The data are complemented by documentary analysis and post-research events.

Findings

The research findings propose that credit officers and customers are influenced by six dynamics under three dimensions: the evaluation procedures (systematic/formal or heuristics); the relationship between customers and bank officers (personal or role relationship); and justification of credit (rational or irrational/situational). Based on the above results, a taxonomy of influential tactics and personality traits and a typological matrix are developed to classify credit decision-makers, who are labelled as BOSS, ROBOT, REBEL and BUDDY.

Research limitations/implications

These case studies are from a private bank in Sri Lanka, hence it could affect the generalization of findings. Therefore, researchers are encouraged to investigate the plausibility of the findings in diverse cultural backgrounds.

Practical implications

Credit decision-makers and credit applicants could make use of these typological matrix and the taxonomy to understand each other and employ more influential approaches and appropriate influential techniques to make effective credit decisions. It also provides more insight into understanding the nature of credit-decisions and decision-makers and, provokes further research.

Originality/value

To the author’s best knowledge, this is the first study in Sri Lanka that considers certain influencing factors of credit decision-making and proposes a conceptual typology to understand those factors.
Topical administration of nanocarrier miRNA‐210 antisense ameliorates imiquimod‐induced psoriasis‐like dermatitis in mice
Authors: Feng Huan , Wu Ruifang , Zhang Suhan , Kong Yi , Liu Zixin , Wu Haijing , Wang Honglin , Su Yuwen , Zhao Ming , Lu Qianjin
Published: November 2019

Psoriasis is a chronic, recurrent inflammatory autoimmune skin disease. Although its etiology and pathogenesis are complex and multifarious, it has been proved to be closely related to dysregulation of immune cell function as well as keratinocyte proliferation/differentiation. Our previous study demonstrated that miRNA‐210 (miR‐210) plays an important role in the formation of skin lesions and immune imbalance in psoriasis. Here, we developed a biomimetic reconstituted high‐density lipoprotein (rHDL) nanocarrier gel containing miR‐210 antisense (NG‐anti‐miR‐210) to investigate its effect on imiquimod (IMQ)‐induced psoriasis‐like dermatitis in mice. We found that topical treatment with NG‐anti‐miR‐210 significantly decreased the expression of miR‐210 in both the skin lesions and splenic CD4+ T cells from IMQ‐induced psoriasis‐like mouse models and ameliorated the dermatitis in terms of the erythema, scales, acanthosis and dermal inflammatory cell infiltration in IMQ‐induced mice. In addition, the proportion of T‐helper (Th)1 and Th17 cells in dermal and splenic cells of IMQ‐treated mice were decreased by application of NG‐anti‐miR‐210, accompanied by decreased interleukin‐17A and γ‐interferon mRNA levels. Therefore, our data demonstrate that topical inhibition of miR‐210 delivered by rHDL nanocarrier effectively alleviates the psoriasis‐like inflammation in mice and provides a potentially effective topical drug for psoriasis.
Challenges in estimating ancestral state reconstructions: the evolution of migration inSylviawarblers as a study case
Authors: PONTI Raquel , ARCONES Angel , VIEITES David R.
Published: November 2019

Our current understanding of how species have evolved is mainly based on comparative phylogenetic methods, which use phylogenies to infer the evolution of traits. The development of ancestral state reconstruction (ASR) methods has provided the tools to reconstruct trait evolution, which are widely used in fields like evolutionary biology, macroecology and paleontology. As there are different elements involved in those analyses, with different levels of uncertainty (i.e. relating to branch length estimation, trait coding, statistical framework, taxon sampling or software), the various combinations of these elements likely have a strong impact on the reconstruction of the evolution of traits, potentially leading to opposite conclusions. To assess the impact of these different elements in ASR, we performed a set of analyses, including all possible combinations of such elements and using the evolution of migratory behavior inSylviawarblers as a case study, which was coded as a continuous or as a discrete character. Our results show that taxon sampling, character coding, tree shape, statistical framework and software all significantly affect ASR, both individually and in combination. Not all reconstructed tree nodes show discrepancies, but in the critical ones most pairwise comparisons between analyses lead to conflicting and unexpectedly antagonistic results (zero migrationvsfully migratory), thus challenging interpretations of trait evolution. We propose some possible solutions to partly inform decisions, involving the method selection and the incorporation of biological or fossil evidence regarding how traits evolve, but our results demand serious rethinking about how the research community currently uses ASR.
Offspring birthweight and placental weight in immigrant women from conflict‐zone countries; does length of residence in the host country matter? A population study in Norway
Authors: Eskild Anne , Sommerfelt Silje , Skau Irene , Grytten Jostein
Published: November 2019

Introduction

We aimed to estimate differences in offspring birthweight and placental weight between Norwegian women and immigrants in Norway from countries with armed conflicts. We also studied whether length of residence in Norway was associated with offspring birthweight and placental weight.

Material and methods

We included in our study all singleton births in Norway at gestational week 28 or beyond during the years 1999‐2014, to mothers who were born in Somalia, Afghanistan, Iraq (total immigrants n = 18 817), or Norway (n = 668 439). Data were obtained from The Medical Birth Registry of Norway and the Central Person Registry of Norway. We estimated the differences between Norwegian and immigrant women in mean offspring birthweight and mean placental weight by applying linear regression analyses. Adjustments were made for maternal age, parity, year of delivery, gestational age at delivery, preeclampsia, and diabetes.

Results

The immigrant women had 206 g (95% CI 199 to 213 g) lower mean offspring birthweight and 16 g (95% CI 14 to 18 g) lower mean placental weight than Norwegian women. Immigrant women with ≥5 years of residence in Norway had higher offspring birthweight (40 g) and higher placental weight (17 g) than immigrant women with <5 years of residence.

Conclusions

Immigrant mothers from Somalia, Afghanistan, and Iraq gave birth to infants and placentas with lower weight than Norwegian women. However, the difference between Norwegian women and immigrant women was reduced by length of residence in Norway.
Corporate environmental performance and financing decisions
Authors: Benlemlih Mohammed , Cai Li
Published: November 2019

We investigate the financing strategies of environmentally responsible firms to understand how they set target capital structures and make incremental financing decisions. Literature shows that firms with better environmental performance have lower risk and better access to financing. However, it is not obvious how these firms choose to finance their investments. Using an extensive data set of U.S. firms, we find that firms with superior environmental performance have significantly lower debt ratios and use mostly short‐term debt for temporary financing needs. In doing so, environmentally responsible firms are able to achieve more tax savings and experience lower costs of financial distress. Our results provide new empirical facts about environmental performance and financing decisions, and they help explain the observed relationship between environmental performance and economic performance.
Plasma and tumoral glypican‐3 levels are correlated in patients with hepatitis C virus‐related hepatocellular carcinoma
Authors: Shimizu Yasuhiro , Mizuno Shoichi , Fujinami Norihiro , Suzuki Toshihiro , Saito Keigo , Konishi Masaru , Takahashi Shinichiro , Gotohda Naoto , Tada Toshifumi , Toyoda Hidenori , Kumada Takashi , Miura Masahiro , Suto Kouzou , Yamaji Taiki , Matsuda Takahisa , Endo Itaru , Nakatsura Tetsuya
Published: November 2019

Glypican‐3 (GPC3) is a cancer antigen expressed in approximately 80% of hepatocellular carcinomas (HCC) and is secreted into the blood. To confirm the effectiveness of GPC3 as a biomarker in HCC, we analyzed the relationship between GPC3 expression levels in cancer cells and in blood in 56 patients with HCC. Preoperative plasma GPC3 levels were determined with an immunoassay, and expression of GPC3 in resected tumors was analyzed by immunohistochemical staining. Median plasma GPC3 level in all HCC cases was 4.6 pg/mL, and tended to be higher in patients with hepatitis C virus (HCV)‐related HCC (HCV group) (9.9 pg/mL) than in patients with hepatitis B virus (HBV)‐related HCC (HBV group) (2.6 pg/mL) or in those without virus infection (None group) (3.0 pg/mL), suggesting that the virus type most likely influences GPC3 secretion. Median percentage of GPC3+ cells in tumors was also higher in the HCV (26.2%) and HBV (11.1%) groups than in the None group (4.2%). In the HCV group, there was a positive correlation between the two parameters (r = 0.66, P < .01). Moreover, receiver operating characteristic analysis predicted >10% GPC3+ cells in a tumor if the cut‐off value was 6.8 pg/mL (sensitivity 80%, specificity 100%; area under the curve 0.875, 95% confidence interval 0.726‐1) in the HCV group. Plasma concentration of GPC3 could be a predictive marker of tumoral GPC3 expression in patients with HCV‐related HCC, suggesting a useful biomarker for immunotherapies targeting GPC3, although larger‐scale validations are needed.
Earthworms in Brazilian no‐tillage agriculture: Current status and future challenges
Authors: Demetrio Wilian C. , Ribeiro Ricardo H. , Nadolny Herlon , Bartz Marie L.C. , Brown George G.
Published: November 2019

No‐tillage (NT) agriculture represents a great advance in soil conservation in tropical and subtropical zones, occupying more than 32 million ha in Brazil in 2017. No‐tillage systems can promote earthworm populations, which can improve soil physical and chemical properties, thus enhancing the benefits of NT for soil conservation and ecosystem services. Furthermore, earthworms can be used as indicators of the quality of NT systems. Here, we summarize the studies that evaluated earthworm populations in NT systems between 1986 and 2016 in Brazil, highlighting important gaps in knowledge. The studies were highly skewed geographically, with most data from southern and south‐eastern Brazil, and had very little information from the two states with the greatest NT area (Mato Grosso and Rio Grande do Sul) which together represent 43% of Brazilʼs NT area. Abundance values ranged from 0 to 660 ind. m−2, with a mean of 91 ± 129 ind. m−2(±SD), and at least 33 species were identified in NT systems. However, 73% of sites were considered to have poor and moderate soil quality based on their earthworm populations, raising concern regarding soil quality levels in Brazilian NT systems. Climate, soil and management conditions are important drivers of earthworm populations in Brazilian NT systems and future earthworm surveys in NT systems should provide ample data on these attributes, as well as on earthworm species, in order to improve their use as soil quality bioindicators.

Highlights

Mean earthworm abundance in Brazilian NT is 91 ± 129 ind. m−2(range 0–660 ind. m−2)

33 species were identified in NT, most endogeic and epi‐endogeic (0 anecics, 1 epigeic)

Around 75% of NT sites sampled in Brazil had moderate to poor earthworm populations

Soil management practices need improvement in many NT systems to increase earthworm populations
An experimental study of creep‐ratchetting behavior of rolled AZ31B magnesium alloy at room temperature
Authors: Meng Li , Chen Wufan , Feng Miaolin
Published: November 2019

To study the interaction effect of creep and ratchetting for rolled AZ31B magnesium alloy at room temperature, a series of stress‐controlled tests were designed. In the tests, four loading types with different mean stresses were considered, and dwell loading was applied to explore the creep effect on the ratchetting. The test results indicated that the sequence of ratchetting and creep loading is crucial for the strain evolution. The amount of twinning/detwinning increased as the mean stress decreased, leading to an exhaustion of nonbasal slip during ratchetting, and then suppressed the creep ductility. However, the creep sequence exerted little influence on the strain shift of ratchetting while large amount of twinning/detwinning was involved.
International capital market and repeated tax competition
Authors: Kasamatsu Satoshi , Ogawa Hikaru
Published: November 2019

We propose an infinitely repeated game of tax competition with an endogenous capital supply. Our results show that the larger the capital supply elasticity to interest rates, the easier it is for interregional tax coordination within a country to be achieved. The capital supply elasticity is lower when countries are less integrated into the international capital market, and vice versa. Thus, our finding suggests that the regions in the country with a lower (higher) degree of integration in the global market are less (more) likely to achieve tax coordination.
Physical Exercise During the Morning School‐Break Improves Basic Cognitive Functions
Authors: Tilp Markus , Scharf Carina , Payer Gerald , Presker Maximilian , Fink Andreas
Published: November 2019

Physical activity has not only been associated with increased physical and mental health, but also with beneficial effects on various cognitive and brain functions. This study investigated the effects of a motor and coordination oriented exercise intervention on academic achievements, attention/concentration ability, and on different facets of creative potential in a sample of school‐aged children between 11 and 14 years. The intervention was conducted during the morning school‐break over a time period of 4 weeks (5 units per week). The intervention was associated with beneficial effects on attention/concentration ability, basic arithmetic competence, and the fluency facet of creative potential. The finding that regular physical exercise during the morning break improves some basic academic and cognitive functions may motivate efforts to implement physical activity programs as promising and effective tools in the everyday school‐routine of the children to stimulate basic neurocognitive functions.
Haustoria – arsenals during the interaction between wheat and Puccinia striiformis f. sp. tritici
Authors: Xu Qiang , Tang Chunlei , Wang Likun , Zhao Congcong , Kang Zhensheng , Wang Xiaojie
Published: November 2019

As an obligate parasite, Puccinia striiformis f. sp. tritici (Pst) forms haustoria to obtain nutrients from plant cells for development, and these structures are essential for pathogen survival. To better understand the contribution of haustoria to the interactions with the host plants, we isolated haustoria from susceptible wheat leaves infected with Pst race CYR31 and sequenced their transcriptome as well as those of urediospores and germ tubes, and compared the three transcriptomes. A total of 3524 up‐regulated genes were obtained from haustoria, of which 73 genes were related to thiamine biosynthesis, glycolysis and lipid metabolic processes. Silencing seven of the genes reduced the growth and development of Pst in wheat. More interestingly, 1197 haustorial secreted proteins (HASPs) were detected in haustoria, accounting for 34% of the total proteins, indicating that these HASPs play important roles in haustorium‐mediated pathogenic progression. Furthermore, 69 HASPs were able to suppress Bax‐triggered programmed cell death in tobacco. Additionally, 46 HASPs significantly reduced callose deposition in wheat using the type III secretion system. This study identified a large number of effectors through transcriptome sequencing, and the results revealed components of metabolic pathways that impact the growth and colonization of the pathogen and indicate essential functions of haustoria in the growth and pathogenicity of Pst.
Plants make galls to accommodate foreigners: some are friends, most are foes
Authors: Harris Marion O. , Pitzschke Andrea
Published: November 2019

At the colonization site of a foreign entity, plant cells alter their trajectory of growth and development. The resulting structure – a plant gall – accommodates various needs of the foreigner, which are phylogenetically diverse: viruses, bacteria, protozoa, oomycetes, true fungi, parasitic plants, and many types of animals, including rotifers, nematodes, insects, and mites. The plant species that make galls also are diverse. We assume gall production costs the plant. All is well if the foreigner provides a gift that makes up for the cost. Nitrogen‐fixing nodule‐inducing bacteria provide nutritional services. Gall wasps pollinate fig trees. Unfortunately for plants, most galls are made for foes, some of which are deeply studied pathogens and pests:Agrobacterium tumefaciens,Rhodococcus fascians,Xanthomonas citri,Pseudomonas savastanoi,Pantoea agglomerans, ‘Candidatus’ phytoplasma, rust fungi,Ustilagosmuts, root knot and cyst nematodes, and gall midges. Galls are an understudied phenomenon in plant developmental biology. We propose gall inception for discovering unifying features of the galls that plants make for friends and foes, talk about molecules that plants and gall‐inducers use to get what they want from each other, raise the question of whether plants colonized by arbuscular mycorrhizal fungi respond in a gall‐like manner, and present a research agenda.
Conservative Versus Surgical Management of Elbow Medial Ulnar Collateral Ligament Injury: A Systematic Review
Authors: Biz Carlo , Crimì Alberto , Belluzzi Elisa , Maschio Nicola , Baracco Riccardo , Volpin Andrea , Ruggieri Pietro
Published: November 2019

Objective

Several studies have been published regarding the treatment of medial ulnar collateral ligament (MUCL) injuries for professional overhead athletes. However, there is a paucity of data regarding non‐professional athletes. The aim of this systematic review was to compare the rate of outcome scores and complications of conservative versus operative treatments both in non‐professional athletes and in non‐sport‐related trauma patients with MUCL lesions.

Methods

A systematic review of the published literature was performed by applying the PRISMA guidelines. A search was conducted using three databases: Medline, Science Direct, and Web of Science. The keywords used were “ulnar collateral ligament injury,” “elbow,” “surgery,” and “conservative treatment”. Patients were divided into three groups: patients who underwent conservative treatment (C‐group), surgical treatment (S‐group), and surgery after a failed conservative treatment (C&S‐group). Clinical outcomes were analyzed: Disability of Arm, Shoulder and Hand (DASH), Conway scale, Carson score, and Kerlan–Jobe Orthopaedic Clinic score (KJOC).

Results

A total of 15 studies were included, evaluating 513 patients. Although good and excellent outcomes were found for most patients during daily and/or sport activities, independently of the type of treatment, the C‐group had better results. Excellent results were found in 98.8% of the C‐group, in 88.1% of the S‐group, and in 87.7% of the C&S‐group. The complication rate in the C‐group was statistically higher compared to the S and C&S groups (P < 0.001). However, its complication rate was higher with lower patient satisfaction.

Conclusions

There is insufficient evidence to establish statistically significant differences in the effects of conservative versus surgical treatments on the functional outcomes of patients with MUCL lesions. However, a period of rehabilitation therapy and the functional request of the single injured subject are useful to discern which patients genuinely require MUCL surgical repair.
Associations between perceptions about siblings' development and emerging adults' adulthood attainment
Authors: Cassinat Jenna R. , Whiteman Shawn D. , Jensen Alexander C.
Published: November 2019

Siblings shape each other's attitudes and behaviors during childhood and adolescence; however, it is less clear if siblings continue to influence each other in emerging adulthood. This study investigated the extent to which emerging adults modeled their siblings in domains of adulthood attainment. Participants included 1,750 emerging adults from the United States between the ages of 18 and 29 years. Data were collected via Amazon Mechanical Turk. Findings showed that perceptions of siblings' adulthood attainment were positively related to emerging adults' development in those same domains. Moreover, the extent to which emerging adults modeled their siblings enhanced these associations; neither birth order nor gender composition moderated these findings. In short, processes of sibling influence continue to be relevant in emerging adulthood.
Aid for trade and international transactions in goods and services
Authors: Hoekman Bernard , Shingal Anirudh
Published: November 2019

The empirical literature on aid for trade (AfT) mainly considers its effects on merchandise trade and investment. In this paper, we provide an in‐depth analysis of the relationship between AfT and trade in services using both aggregate and bilateral data. We find a statistically weak effect of AfT on both goods and services trade in our aggregate analysis once we account for endogeneity in the AfT–trade relationship. In contrast, the bilateral analysis suggests that AfT, in particular that allocated to services activities, especially economic infrastructure, has a positive effect on recipients’ merchandise exports to donor countries. This novel finding is robust across different lag structures and provides evidence of complementarities between services AfT and goods trade.
Prevalence of depression after moderate to severe traumatic brain injury among adolescents and young adults: A systematic review
Authors: Ryttersgaard Trine O. , Johnsen Søren P. , Riis Jens Ø. , Mogensen Poul H. , Bjarkam Carsten R.
Published: November 2019

To review the prevalence of depression among adolescents and young adults after moderate to severe TBI. A systematic literature search was conducted on literature published up to December 2018 in PubMed, EMBASE, Cochrane and PsychInfo. A systematic review of the identified literature was based on PRISMA guidelines. Risk of Bias was evaluated based on the aspects of Risk of Bias assessment described by the Agency of Health Research and Quality. Seven studies were deemed eligible and information on the prevalence of depression among adolescents and young adults (age 13–35) after moderate to severe TBI was extracted. Depression was assessed at 12 months (n = 2), >12 months (n = 2) or at varying times (n = 3) after TBI. The identified studies reported a prevalence proportion of depression from 1.6% to 60%. The Risk of Bias assessment showed a range of study quality with the selection of subjects and analysis of attrition being problematic. Although literature is sparse and of varying quality, depression was found to be common among adolescents and young adults with moderate to severe TBI which implies a need to focus on depression in the rehabilitation process and calls for further research.
Prediction of Surface Hardness in Laser-Assisted Milling
Authors: Feng Yixuan , Hung Tsung-Pin , Lu Yu-Ting , Lin Yu-Fu , Hsu Fu-Chuan , Lin Chiu-Feng , Lu Ying-Cheng , Liang Steven Y.
Published: November 2019

The control of work hardening in laser-assisted milling process while keeping a desirable cutting efficiency is quite challenging. Surface hardness is a good indicator of the work hardening. Therefore, it is valuable to predict surface hardness in laser-assisted milling such that the effects of process parameters can be better quantified to facilitate process planning. In the current study, a general surface hardness predictive model based on theories of metal machining and microstructure evolution in laser-assisted milling process is proposed to describe the grain size variation-induced hardness change. The laser preheating temperature field is first calculated by treating the laser beam as a moving heat source. Then, the oblique milling process is transferred to equivalent orthogonal cutting process at each rotation angle to predict the grain size dependent on dynamic recrystallization process. The inverse relationship between the grain diameter and surface hardness is applied to decide grain size variation-induced hardness change. The model is validated through laser-assisted milling experiments on Ti-6Al-4V and Ti-6Al-4V ELI. The proposed predictive model is able to match the experimental measurements in all cases with an average error of 3% for Ti-6Al-4V and 3.3% for Ti-6Al-4V ELI. In addition, a sensitivity analysis is conducted on Ti-6Al-4V to study the influences of cutting speed, depth of cut, laser power, and laser-tool distance on hardness. The proposed analytical model is valuable for providing a fast, credible, and physics-based method for the prediction of surface hardness in laser-assisted milling of various materials. Through sensitivity analysis, the model is able to guide the selection of cutting and laser parameters when the control of surface hardness is the main target.
A Database Framework for the Characterization and Classification of Parametric Models Based on Complexity Metrics to Support Data Analytics
Authors: Camba Jorge D. , Contero Manuel , Pérez-López David , Company Pedro
Published: November 2019

We present a database architecture for exploring, classifying, and visualizing feature-based parametric CAD models based on quantitative complexity metrics. The system consists of (1) an external relational database structure where models are stored along with their graph representation and the numerical values of each complexity metric, (2) a client module that is integrated in the user’s CAD system and facilitates navigation within the repository, and (3) a report generation module that allows exporting CAD complexity data from the external repository to other applications for validation and analysis. In this paper, we justify the need for our system in the context of data analytics and discuss the rationale of its design as well as its architecture and implementations details. Finally, we describe a use case that illustrates the application of our framework in the characterization and evaluation of CAD models.
Improvement on Straightness of Micro-Motor Shaft Considering Stress Concentration Caused by the Grooves
Authors: Guo Zexing , Lu Hong , Zhang Jinglin , Zang Yue , Zhang Weixin , He Jianying , Liu Qiong
Published: November 2019

Motor shaft is one of the most important parts of motor, which is widely used in industrial field. The straightness of the shaft has a potentially significant effect on motor performance, which is determined by the straightening process in the manufacturing process of the shaft. Considering the grooved characteristics on the micro-motor shaft and using the classical material mechanics principle, the stress and deformation models of the circular shaft with the grooves during the straightening process are established in this paper. By deriving the straighttening stroke-initial deflection model, an accurate and practical relationship between the straightening stroke and the initial deflection was provided. In order to verify the theoretical straightening model, some grooved shaft specimens are designed and manufactured for the straightening experiments. Through the simulation and experimental research, the straightening stroke-initial deflection model for the micro-motor shaft is compared and analyzed, and the correctness and feasibility of the model is verified.
Straightening Process of Straight Metal Pipe Considering the Flattening Effect
Authors: Lian Yang , Lu Hong , Ma Mingtian , He Jianying , Liu Qiong , Cheng Qian , Qiao Yu
Published: November 2019

Straight metal pipes are widely used in petroleum exploration and transmission equipment systems. Straightening is one of effective methods for ensuring or repairing the bending during straight metal pipe rolling, heat treatment, assembly and operational application. However, the flatten phenomenon of straight metal pipe during straightening process is unavoidable. Therefore, it is significant to study the flatten phenomenon of straight metal pipe in straightening process. Based on the theory of elastoplastic deformation, the flatten phenomenon of straight metal pipe is analyzed. Further, the straightening stroke model of straight metal pipe for guiding the straighten operation is established. Afterwards, the theoretical straightening stroke model is analyzed on the basis of simulation. Finally, the experimental system was built up. A series of related experiments were carried out to verify the rationality of the model.
Twinning Behavior in Magnesium Alloys Processed by Laser Shock Peening
Authors: Mao Bo , Liao Yiliang , Li Bin
Published: November 2019

In this paper, the surface microstructure evolution of an AZ31B magnesium (Mg) alloy during laser shock peening (LSP) was investigated. Particular attention was paid to the deformation twinning behavior, which plays an important role in the mechanical properties of Mg alloys. The effect of laser intensity on the twinning distribution was investigated. Twin-twin interactions during LSP process were characterized. The mechanism responsible for the formation of gradient twinning microstructure and twinning-induced hardening effect were discussed.
Grey Relation Approach in Abrasive Jet Machining Process
Authors: Paul Lijo , Babu J.
Published: November 2019

Micro machining of conducting and non-conducting materials with high accuracy has great demand in industries especially in machining of ceramic, brittle materials. Abrasive Jet Machining (AJM) has shown tremendous application especially in machining of hard and brittle materials. In the present paper drilling of soda lime glass has been carried out to determine the machinability under different controlling parameters. A set of L9 series experiments were carried out by varying process parameters such as Stand Off Distance (SOD), Silicon carbide abrasive particles mesh sizes and jet pressure. Material Removal Rate (MRR) and Radial Over Cut (ROC), were taken as the output responses and are optimised with multi objective optimisation.
An Integrated DEM-FEM Model for Shot Peening Applications
Authors: Bobba Dhanooj , Ramaprabhu Praveen , Cherukuri Harish P.
Published: November 2019

Shot peening is a commonly used technique for improving the fatigue life of machine components by inducing compressive residual stresses in the surface layers. This process involves plastically deforming the surface layers by impacting with spherical particles at high speeds. The induced residual compressive stresses resist crack propagation and thus increase the fatigue life. The intensity of shot peening, measured using the Almen test, is an essential quantity for ensuring shot peening effectiveness and repeatability. It depends on various process parameters such as the shot speed, shot size, shot material, impact direction, and flow rate. In this study, a novel computational model is developed to simulate the Almen intensity tests on a Type-C strip accurately. The model uses a coupled technique based on the discrete element method (DEM) and the conventional finite element method (FEM). The predicted Almen intensity values agree with analytically calculated values. Results from the parametric studies conducted to analyze the influence of various parameters on the Almen intensity indicate that many different combinations of these parameters can obtain a given Almen intensity although the residual stress fields may vary.
Enhancing Conductivity and Corrosion Resistance by Organic Coatings on AZ31 Magnesium Alloy Treated by Micro-Arc Oxidation
Authors: Zhang Xiuping , Li Lei , Mu Yaozhao , Xie Yanxiang , Dai Jun , Shi Jing
Published: November 2019

In this study, an organic coating, in combination of a micro-arc oxidation ceramic layer, was prepared on the surface of a magnesium alloy (AZ31) to achieve both functions of corrosion resistance and electrical conductivity. By using carbon black as conductive particles and epoxy resin as matrix, organic coatings of various weight fractions were applied on the AZ31 surface treated by micro-arc oxidation through adjusting the contents of the conductive particles and non-conductive matrix. Electrical conductivity and corrosion resistance of organic coatings were measured. The results show that the organic coatings can improve the electrical conductivity of the AZ31 material treated by micro-arc oxidation, and the conductivity changes with the ratio between the carbon black particles and non-conductive matrix. The smallest resistance value of the organic coatings reached 130Ω. Also, the organic coating can further improve the corrosion resistance of the AZ31 material. The electrochemical corrosion tests show that the corrosion potential of the AZ31 material with composite coatings was at least 0.6V higher than that of AZ31 only with micro-arc oxidation treatment.
On the Impact of Wireless Communications on Controlling a Two-Dimensional Gantry System
Authors: Kashef Mohamed , Candell Richard , Foufou Sebti
Published: November 2019

Industrial wireless is essential to achieve the vision of future manufacturing systems which are highly dynamic and reconfigurable, and communicate large amounts of data. Main challenges of wireless deployment include the stochastic nature of the wireless channels and the harsh industrial transmission environment. In this work, a typical two-dimensional gantry system is controlled by a local controller which receives G-code commands wirelessly over a Wi-Fi network. The industrial wireless channel is replicated using a radio frequency (RF) channel emulator where various scenarios are considered and various wireless channel parameters are studied. The movement of the gantry system tool is tracked using a vision tracking system to quantify the impact of the wireless channel on the system performance. Numerical results are presented including the total run time of an industrial process and the dwell times at various positions through the process.
Effects of Particle Size on Biomass Pretreatment for Biofuel Production
Authors: Yang Yang , Sun Mingman , Deines Timothy , Zhang Meng , Li Jun , Wang Donghai
Published: November 2019

Biofuel production needs to be more efficient than its current status to increase its competitiveness. The multistep biofuel production is consisted of processes on biomass preprocessing and bioconversion stages. As a crucial parameter, biomass particle size has significant effects on both stages. It is essential to have an insightful understanding of the effects of particle size on sugar yield. Although numerous studies have been performed to meet this objective, there is no commonly accepted guideline on how to select particle size. One possible reason for this gap is the effects of particle size vary when different biomass pretreatment methods are employed. In this study, an assessment on the relationship between particle size and sugar yield was performed for four pretreatment methods. Three particle sizes (1, 4, and 8 mm) of corn stover and switchgrass biomass were used in supercritical CO2, dilute acid (H2SO4), dilute alkaline (Na2CO3), and metal oxide (MgO) pretreatments. Biomass compositional analyses were conducted before and after each pretreatment. Pretreatment solid recovery and sugar recovery rates were calculated. Enzymatic hydrolysis sugar yield and efficiency were used to evaluate the performance of hydrolysis and total sugar yield was used to interpret how much sugar a unit dry weight of biomass (before pretreatment) can yield through pretreatment and enzymatic hydrolysis combined. It was found that particle size was a weak indicator of enzymatic hydrolysis efficiency. There was little value in reducing particle size below 8 mm in order to overcome the resistance imposed by biomass structure on cellulose and xylan hydrolysis.
Development of Novel Hybrid Manufacturing Technique for Manufacturing Support Structures Free Complex Parts
Authors: Khan Haris Ali , Ademujimi Toyosi
Published: November 2019

This study unearths a novel approach utilizing conventional subtractive manufacturing technology (5-axis CNC milling center) to realize additively manufactured complex geometries without employing support structures. The proposed approach was based on benefiting from the precision and accuracy of subtractive manufacturing while leveraging the freedom of design of additive manufacturing (AM) process. The desired objectives were achieved in a three-stepped methodology where initially the CNC machine was modified to adapt the 3D printing protocols while in the second step, additional hardware was retrofitted on the conventional CNC machine making it compatible to print 3D parts. A “geometric subsection” approach was adopted as the third step where the desired printed part was divided in different subsections based on the overhang angles and the rotational axes of the CNC machine was then utilized in a manner to eliminate the need for support structures. The manufactured AM part can then be post-processed employing the same machining platform. The proposed approach thereby also served as a next step in evolution of done-in-one processes by printing near-net shape components through additive manufacturing and then promptly acquiring the net shape through subtractive manufacturing techniques.
Microwave-Assisted Processing of Regenerated Silk Fibroin Films
Authors: Abdulhafez Moataz , Cho Se Youn , Tomaraei Golnaz , Bedewy Mostafa
Published: November 2019

Regenerated silk fibroin (RSF) is an emerging material derived from natural silk. Thin RSF films are transparent, biocompatible and biodegradable, which makes them suitable for many applications, such as flexible/conformal and transient electronics, bioresorbable devices, bioresists for lithography, and edible food protective coatings. To realize these applications, controlling and tuning the properties of RSF films is required to fully exploit their unique mechanical, optical, and degradation properties. Here, a new approach for tuning these properties is presented based on inducing rapid molecular structure transformations in fibroins via microwave heating. Transparent RSF films were post-treated by microwave irradiation, resulting in the transition of amorphous silk fibroin structure to a more α-helix dominant secondary structure. By increasing the microwave irradiation duration, an increase of helix secondary structure was observed. We use amide-I band Fourier-transform infrared spectroscopy (FTIR) of the films to characterize the secondary structure of fibroins. Moreover, we show that silicon substrates coated with 100 nm thick RSF films by spin casting, exhibit higher stability in water after microwave irradiation for up to 10 minutes, confirming a conformational change in the RSF secondary structure towards more stable α-helical rich motifs. Our results show that microwave treatment can be a new high throughput approach for tailoring the properties and structure of functional RSF-based films in a scalable and sustainable manufacturing process, when compared to other post processing techniques.
Improved Co-Scheduling of Printing Path Scanning for Collaborative Additive Manufacturing
Authors: Jiang Zhengqian , Psulkowski Sean , Nwodu Arriana , Wang Hui , Dickens Tarik
Published: November 2019

Additive manufacturing processes, especially those based on fused filament fabrication (FFF) mechanism, have relatively low productivity and suffer from production scalability issue. One solution is to adopt a collaborative additive manufacturing system that is equipped with multiple extruders working simultaneously to improve productivity. The collaborative additive manufacturing encounters a grand challenge in the scheduling of printing path scanning by different extruders. If not properly scheduled, the extruders may collide into each other or the structures built by earlier scheduled scanning tasks. However, there existed limited research addressing this problem, in particular, lacking the determination of the scanning direction and the scheduling for sub-path scanning. This paper deals with the challenges by developing an improved method to optimally break the existing printing paths into sub-paths and assign these generated sub-paths to different extruders to obtain the lowest possible makespan. A mathematical model is formulated to characterize the problem, and a hybrid algorithm based on an evolutionary algorithm and a heuristic approach is proposed to determine the optimal solutions. The case study has demonstrated the application of the algorithms and compared the results with the existing research. It has been found that the printing time can be reduced by as much as 41.3% based on the available hardware settings.
Modeling of Material Removal in Atomized Dielectric-Based Electrical Discharge Machining (EDM)
Authors: Tanveer Asif , Kapoor Shiv G. , Mujumdar Soham S.
Published: November 2019

Atomized dielectric-based electrical discharge machining (EDM) is an emerging technology in which the dielectric between the electrodes is supplied in the form of a thin film using a spray atomizer. This novel machining process uses significantly less quantities of dielectric compared to the conventional EDM while resulting in higher material removal rates and better debris flushing. This paper presents a model-based investigation of the atomized dielectric-based EDM to study the effect of the dielectric film flow on material removal. A melt-pool formation and material removal model is developed to predict the material removal in terms of crater shapes during a single EDM discharge. The atomization spray parameters are varied in order to produce different dielectric film velocities. The model accurately captures the asymmetry in crater shapes caused by the dielectric film flow and predicts the crater diameter and depth, however, the model overestimates the crater sizes observed in experiments.
Noise-induced hearing loss and its prevention: Integration of data from animal models and human clinical trials
Authors: Le Prell Colleen G. , Hammill Tanisha L. , Murphy William J.
Published: November 2019

Animal models have been used to gain insight into the risk of noise-induced hearing loss (NIHL) and its potential prevention using investigational new drug agents. A number of compounds have yielded benefit in pre-clinical (animal) models. However, the acute traumatic injury models commonly used in pre-clinical testing are fundamentally different from the chronic and repeated exposures experienced by many human populations. Diverse populations that are potentially at risk and could be considered for enrollment in clinical studies include service members, workers exposed to occupational noise, musicians and other performing artists, and children and young adults exposed to non-occupational (including recreational) noise. Both animal models and clinical populations were discussed in this special issue, followed by discussion of individual variation in vulnerability to NIHL. In this final contribution, study design considerations for NIHL otoprotection in pre-clinical and clinical testing are integrated and broadly discussed with evidence-based guidance offered where possible, drawing on the contributions to this special issue as well as other existing literature. The overarching goals of this final paper are to (1) review and summarize key information across contributions and (2) synthesize information to facilitate successful translation of otoprotective drugs from animal models into human application.
Mechanisms to Attenuate Load in the Intact Limb of Transtibial Amputees When Performing a Unilateral Drop Landing
Authors: Moudy Sarah C. , Tillin Neale A. , Sibley Amy R. , Strike Siobhán
Published: November 2019

Individuals with unilateral transtibial amputations experience greater work demand and loading on the intact limb compared with the prosthetic limb, placing this limb at a greater risk of knee joint degenerative conditions. It is possible that increased loading on the intact side may occur due to strength deficits and joint absorption mechanics. This study investigated the intact limb mechanics utilized to attenuate load, independent of prosthetic limb contributions and requirements for forward progression, which could provide an indication of deficiencies in the intact limb. Amputee and healthy control participants completed 3 unilateral drop landings from a 30-cm drop height. Joint angles at touchdown; range of motion; coupling angles; peak powers; and negative work of the ankle, knee, and hip were extracted together with isometric quadriceps strength measures. No significant differences were found in the load or movement mechanics (P ≥ .31, g ≤ 0.42), despite deficits in isometric maximum (20%) and explosive (25%) strength (P ≤ .13, g ≥ 0.61) in the intact limb. These results demonstrate that, when the influence from the prosthetic limb and task demand are absent, and despite deficits in strength, the intact limb adopts joint mechanics similar to able-bodied controls to attenuate limb loading.
Thiol-based direct threat sensing by the stress-activated protein kinase Hog1
Authors: Guerra-Moreno Angel , Prado Miguel A. , Ang Jessie , Schnell Helena M. , Micoogullari Yagmur , Paulo Joao A. , Finley Daniel , Gygi Steven P. , Hanna John
Published: November 2019

Arsenic directly stimulates the kinase Hog1 to promote the gene expression required for arsenic detoxification in yeast.