bluuebunny/crossref_metadata_2025 huggingface dataset:
Pulse Pressure Variation and Weight-Loss Percentage Predict Hypotension After Anesthesia Induction in Neurosurgery Patients: A Prospective, Observational, Blinded Study
Authors: Ali Achmet , Altiparmak Oguzhan , Tetik Aylin , Altun Demet , Sivrikoz Nukhet , Buget Mehmet , Bolsoy Sahika , Yaman Nihan , Akinci Ibrahim O.
Published: June 2016

Background:

Hypotension after anesthesia induction is a common problem and is partly related to patient volume status. The present study aimed to investigate the correlation between blood pressure change and pulse pressure variation (PPV), and percentage of weight loss while determining threshold for hypotension by receiver operating characteristic analysis.

Methods:

We analyzed 231 neurosurgery patients. In all patients, propofol was used for standard anesthesia induction. Patient demographics, medical histories, fasting duration, percentage weight loss, baseline blood pressure, and PPV during normal tidal volume breathing and that during forced inspiratory breathing (PPVfi) were recorded. Hemodynamic changes within 10 minutes of intubation were observed. Patients developing hypotension and severe hypotension were determined; lowest mean arterial pressure (MAP) and systolic arterial pressure (SAP) values were recorded, and their differences relative to baseline values were calculated.

Results:

The incidence of hypotension was 18.6%. Both percentage weight loss and PPVfi were correlated with the changes in MAP and SAP. A PPVfi>14 identified all observed hypotensive episodes with 86% sensitivity and 86.2% specificity, whereas percentage weight loss >1.75% identified all observed hypotensive episodes with 81.4% sensitivity and 70.7% specificity. Furthermore, PPVfi>16.5 identified severe hypotension with 85% sensitivity and 90.5% specificity, whereas percentage weight loss >1.95% identified severe hypotension with 85% sensitivity and 73% specificity.

Conclusions:

Percentage weight loss and PPVfi are good predictors of hypotension after anesthesia induction and, thus, may allow anesthesiologists to adopt preventative measures and ensure safer anesthesia induction.
Relationship Between African-American Race and Delirium in the ICU
Authors: Khan Babar A. , Perkins Anthony , Hui Siu L. , Gao Sujuan , Campbell Noll L. , Farber Mark O. , Boustani Malaz A.
Published: June 2016

Objectives:

Delirium is a highly prevalent syndrome of acute brain dysfunction among critically ill patients that has been linked to multiple risk factors, such as age, preexisting cognitive impairment, and use of sedatives; but to date, the relationship between race and delirium is unclear. We conducted this study to identify whether African-American race is a risk factor for developing ICU delirium.

Design:

A prospective cohort study.

Setting:

Medical and surgical ICUs of a university-affiliated, safety net hospital in Indianapolis, IN.

Patients:

A total of 2,087 consecutive admissions with 1,008 African Americans admitted to the ICU services from May 2009 to August 2012.

Interventions:

None.

Measurements and Main Results:

Incident delirium was defined as first positive Confusion Assessment Method for the ICU result after an initial negative Confusion Assessment Method for the ICU; and prevalent delirium was defined as positive Confusion Assessment Method for the ICU on first Confusion Assessment Method for the ICU assessment. The overall incident delirium rate in African Americans was 8.7% compared with 10.4% in Caucasians (p = 0.26). The prevalent delirium rate was 14% in both African Americans and Caucasians (p = 0.95). Significant age and race interactions were detected for incident delirium (p = 0.02) but not for prevalent delirium (p = 0.3). The hazard ratio for incident delirium for African Americans in the 18–49 years age group compared with Caucasians of similar age was 0.4 (0.1–0.9). The hazard and odds ratios for incident and prevalent delirium in other groups were not different.

Conclusions:

African-American race does not confer any additional risk for developing incident or prevalent delirium in the ICU. Instead, younger African Americans tend to have lower rates of incident delirium compared with Caucasians of similar age.
Fatal Case of Primary Cutaneous Aggressive T-Cell Lymphoma Switching From a CD4+ to a CD8+ Phenotype: Progressive Disease With Bexarotene and Romidepsin Treatment
Authors: Johnson William T. , Leeman-Neill Rebecca J. , Patel Parth , Ho Jonhan , Grandinetti Lisa M. , Jedrych Jaroslaw , Craig Fiona E.
Published: June 2016

A 77-year-old white male presented to the clinic with two isolated cutaneous tumors on his forehead. A cutaneous biopsy showed a focally folliculotropic CD4+ cutaneous lymphoma. The tumors were irradiated with a complete response, and he was started on oral bexarotene. He experienced localized cutaneous relapse 3 months into treatment. These new tumors now revealed a surprisingly CD8+ cytotoxic phenotype, but with the same clone. A systemic workup was negative. His regimen was switched to romidepsin, and he was treated with local radiation again. Another 3.5 months passed in remission until he developed widespread cutaneous tumors. Positron emission tomography/computed tomography revealed multifocal systemic disease involving his diaphragm, liver, distal duodenum, proximal jejunum, anterior chest wall including pectoral muscles, and lungs without significant adenopathy. He died a few days later. Given his full clinical and pathological course, he was given the diagnosis of an aggressive primary cutaneous T-cell lymphoma, unspecified.
Pycnogenol Reduces Toll-Like Receptor 4 Signaling Pathway-Mediated Atherosclerosis Formation in Apolipoprotein E-Deficient Mice
Authors: Liu Rui , Fan Bin , Cong Huiying , Ikuyama Shoichiro , Guan Haixia , Gu Jianqiu
Published: June 2016

Pycnogenol (PYC) is an extract from French maritime pine bark. Its antioxidative and anti-inflammatory effects have been shown to be beneficial for atherosclerosis. Here, we tested whether PYC could suppress high cholesterol and fat diet (HCD)-induced atherosclerosis formation in apolipoprotein E (apoE)-deficient mice. In our study, PYC suppressed oxidized low-density lipoprotein (ox-LDL)-induced lipid accumulation in peritoneal macrophages. Apolipoprotein E-deficient mice were orally administered PYC or a control solvent for ten weeks, and these mice were fed a standard diet or high cholesterol and fat diet during the latter eight weeks. Pycnogenol markedly decreased the size of atherosclerotic lesions induced by high cholesterol and fat diet compared with the nontreated controls. In addition, TLR4 expression in aortic sinus was stimulated by high cholesterol and fat diet feeding and was significantly reduced by PYC. A mechanistic analysis indicated that lipopolysaccharide (LPS) significantly increased expression of fatty acid binding protein (aP2) and macrophage scavenger receptor class A (SR-A), which were blocked by a JNK inhibitor. Furthermore, PYC inhibited the lipopolysaccharide-induced upregulation of aP2 and scavenger receptor class A via the JNK pathway. In conclusion, PYC administration effectively attenuates atherosclerosis through the TLR4-JNK pathway. Our results suggest that PYC could be a potential prophylaxis or treatment for atherosclerosis in humans.
Seizure Prophylaxis Guidelines Following Traumatic Brain Injury: An Evaluation of Compliance
Authors: Zaman Anwar , Dubiel Randi , Driver Simon , Bennett Monica , Diggs Vincent , Callender Librada
Published: June 2016

Objective:

To determine degree of adherence to guidelines for seizure prophylaxis following traumatic brain injury (TBI).

Setting:

Tertiary care level 1 trauma center and affiliated inpatient rehabilitation facility.

Participants:

A total of 173 individuals with TBI who required inpatient rehabilitation from January 1, 2007, to December 31, 2013.

Design:

Retrospective medical record review.

Main Measures:

Overutilization rate of prophylactic antiepileptic drugs (AEDs); failure to stop rate of AED utilization upon admission to and during inpatient rehabilitation; and duration of overutilization.

Results:

Of the 173 participants included, 77 were started on seizure prophylaxis at hospital presentation and 96 were not. Of the 77 participants, 11 had a posttraumatic seizure. Of the 66 remaining, 18 participants (10.4%) were continued on AEDs for more than 7 days after injury. Of these 18 participants, 12 were continued on AEDs without indication upon admission to inpatient rehabilitation. Finally, 8 of the 12 were continued on AEDs at discharge from rehabilitation, resulting in a failure to stop rate of 66.67%.

Conclusion:

Despite existing guidelines for stopping seizure prophylaxis after TBI, some patients remain on AEDs and may be inappropriately exposed to possible medication side effects. These findings highlight the importance of communication at the time of rehabilitation transfer and the need for ongoing education about AED guidelines.
The gut in trauma
Authors: Patel Jayshil J. , Rosenthal Martin D. , Miller Keith R. , Martindale Robert G.
Published: June 2016

Purpose of review

The purpose of this review is to describe established and emerging mechanisms of gut injury and dysfunction in trauma, describe emerging strategies to improve gut dysfunction, detail the effect of trauma on the gut microbiome, and describe the gut–brain connection in traumatic brain injury.

Recent findings

Newer data suggest intraluminal contents, pancreatic enzymes, and hepatobiliary factors disrupt the intestinal mucosal layer. These mechanisms serve to perpetuate the inflammatory response leading to multiple organ dysfunction syndrome (MODS). To date, therapies to mitigate acute gut dysfunction have included enteral nutrition and immunonutrition; emerging therapies aimed to intestinal mucosal layer disruption, however, include protease inhibitors such as tranexamic acid, parenteral nutrition-supplemented bombesin, and hypothermia. Clinical trials to demonstrate benefit in humans are needed before widespread applications can be recommended.

Despite resuscitation, gut dysfunction promotes distant organ injury. In addition, postresuscitation nosocomial and iatrogenic ‘hits’ exaggerate the immune response, contributing to MODS. This was a provocative concept, suggesting infectious and noninfectious causes of inflammation may trigger, heighten, and perpetuate an inflammatory response culminating in MODS and death. Emerging evidence suggests posttraumatic injury mechanisms, such as intestinal mucosal disruption and shifting of the gut microbiome to a pathobiome. In addition, traumatic brain injury activates the gut–brain axis and increases intestinal permeability.
A Study of Gene Expression of Survivin, its Antiapoptotic Variants, and Targeting Survivin In Vitro for Therapy in Retinoblastoma
Authors: Samuel Jaisy , Kanwar Rupinder K. , Kanwar Jagat R. , Khetan Vikas , Krishnakumar Subramanian
Published: June 2016

Apoptosis is a natural process regulated by apoptotic and antiapoptotic molecules. We investigated mRNA expression of survivin and its splice variants, along with B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X (Bax), in a cohort of 20 retinoblastoma (RB) tumors by real-time polymerase chain reaction. We hypothesized a correlation between the Bcl-2/Bax and survivin splice variants and also that expression of these would be associated with clinicopathologic features of tumors. The Bcl-2 expression was significantly higher (P<0.001) in RB, and Bcl-2/Bax ratio was remarkably higher in poorly differentiated tumors. A statistically significant higher expression of Survivin-WT (wild type) compared with its variant Survivin-2β (P<0.05) was observed. Bcl-2 did not exhibit positive correlation with any of the survivin variants except Survivin-2β, whereas Bax exhibited significant (P<0.05) correlation with the variants. Thus, it could be suggested that a superior player out of a likely interaction between the variants and Bcl-2/Bax uses its activity for the progression of RB. Silencing of Survivin-WT in the Y79 cell line was studied by siRNA technology and cell-permeable dominant negative survivin (SurR9-C84A). siRNA showed higher proapoptotic effects and increased caspase 3/7 activity in Y79 cells. Effective internalization of SurR9-C84A in Y79 cells induced cytotoxic effects. Thus, the current study confirms survivin as a promising target for therapy.
The Cost-Effectiveness of Syphilis Screening Among Men Who Have Sex With Men: An Exploratory Modeling Analysis
Authors: Chesson Harrell W. , Kidd Sarah , Bernstein Kyle T. , Fanfair Robyn Neblett , Gift Thomas L.
Published: June 2016

We adapted a published model to estimate the costs and benefits of screening men who have sex with men for syphilis, including the benefits of preventing syphilis-attributable human immunodeficiency virus. The cost per quality-adjusted life year gained by screening was <US $0 (cost-saving) and US $16,100 in the dynamic and static versions of the model, respectively.
Droplet-based microfluidics for artificial cell generation: a brief review
Authors: Martino Chiara , deMello Andrew J.
Published: June 2016

Artificial cells are best defined as micrometre-sized structures able to mimic many of the morphological and functional characteristics of a living cell. In this mini-review, we describe progress in the application of droplet-based microfluidics for the generation of artificial cells and protocells.
Single mode waveguide platform for spontaneous and surface-enhanced on-chip Raman spectroscopy
Authors: Dhakal Ashim , Peyskens Frédéric , Clemmen Stéphane , Raza Ali , Wuytens Pieter , Zhao Haolan , Le Thomas Nicolas , Baets Roel
Published: June 2016

We review an on-chip approach for spontaneous Raman spectroscopy and surface-enhanced Raman spectroscopy based on evanescent excitation of the analyte as well as evanescent collection of the Raman signal using complementary metal oxide semiconductor (CMOS)-compatible single mode waveguides. The signal is either directly collected from the analyte molecules or via plasmonic nanoantennas integrated on top of the waveguides. Flexibility in the design of the geometry of the waveguide, and/or the geometry of the antennas, enables optimization of the collection efficiency. Furthermore, the sensor can be integrated with additional functionality (sources, detectors, spectrometers) on the same chip. In this paper, the basic theoretical concepts are introduced to identify the key design parameters, and some proof-of-concept experimental results are reviewed.
Adaptation of sensor morphology: an integrative view of perception from biologically inspired robotics perspective
Authors: Iida Fumiya , Nurzaman Surya G.
Published: June 2016

Sensor morphology, the morphology of a sensing mechanism which plays a role of shaping the desired response from physical stimuli from surroundings to generate signals usable as sensory information, is one of the key common aspects of sensing processes. This paper presents a structured review of researches on bioinspired sensor morphology implemented in robotic systems, and discusses the fundamental design principles. Based on literature review, we propose two key arguments: first, owing to its synthetic nature, biologically inspired robotics approach is a unique and powerful methodology to understand the role of sensor morphology and how it can evolve and adapt to its task and environment. Second, a consideration of an integrative view of perception by looking into multidisciplinary and overarching mechanisms of sensor morphology adaptation across biology and engineering enables us to extract relevant design principles that are important to extend our understanding of the unfinished concepts in sensing and perception.
Infrastructure sensing
Authors: Soga Kenichi , Schooling Jennifer
Published: June 2016

Design, construction, maintenance and upgrading of civil engineering infrastructure requires fresh thinking to minimize use of materials, energy and labour. This can only be achieved by understanding the performance of the infrastructure, both during its construction and throughout its design life, through innovative monitoring. Advances in sensor systems offer intriguing possibilities to radically alter methods of condition assessment and monitoring of infrastructure. In this paper, it is hypothesized that the future of infrastructure relies on smarter information; the rich information obtained from embedded sensors within infrastructure will act as a catalyst for new design, construction, operation and maintenance processes for integrated infrastructure systems linked directly with user behaviour patterns. Some examples of emerging sensor technologies for infrastructure sensing are given. They include distributed fibre-optics sensors, computer vision, wireless sensor networks, low-power micro-electromechanical systems, energy harvesting and citizens as sensors.
Monogamy promotes worker sterility in insect societies
Authors: Davies Nicholas G. , Gardner Andy
Published: June 2016

Inclusive-fitness theory highlights monogamy as a key driver of altruistic sib-rearing. Accordingly, monogamy should promote the evolution of worker sterility in social insects when sterile workers make for better helpers. However, a recent population-genetics analysis (Olejarzet al.2015) found no clear effect of monogamy on worker sterility. Here, we revisit this analysis. First, we relax genetic assumptions, considering not only alleles of extreme effect—encoding either no sterility or complete sterility—but also alleles with intermediate worker-sterility effects. Second, we broaden the stability analysis—which focused on the invasibility of populations where either all workers are fully-sterile or all workers are fully-reproductive—to identify where intermediate pure or mixed evolutionarily-stable states may occur. Finally, we consider additional, demographically-explicit ecological scenarios relevant to worker non-reproduction. This extended analysis demonstrates that an exact population-genetics approach strongly supports the prediction of inclusive-fitness theory that monogamy promotes sib-directed altruism in social insects.
Scanning the Horizon: Towards transparent and reproducible neuroimaging research
Authors: Poldrack Russell A. , Baker Chris I. , Durnez Joke , Gorgolewski Krzysztof J. , Matthews Paul M. , Munafò Marcus , Nichols Thomas E. , Poline Jean-Baptiste , Vul Edward , Yarkoni Tal
Published: June 2016

Functional neuroimaging techniques have transformed our ability to probe the neurobiological basis of behaviour and are increasingly being applied by the wider neuroscience community. However, concerns have recently been raised that the conclusions drawn from some human neuroimaging studies are either spurious or not generalizable. Problems such as low statistical power, flexibility in data analysis, software errors, and lack of direct replication apply to many fields, but perhaps particularly to fMRI. Here we discuss these problems, outline current and suggested best practices, and describe how we think the field should evolve to produce the most meaningful answers to neuroscientific questions.
microRNA-mRNA interaction identification in Wilms tumor using principal component analysis based unsupervised feature extraction
Authors: Taguchi Y-h.
Published: June 2016

Wilms tumor is one of lethal child renal cancers, for which no known disease causing mechanisms exist. In this paper, we tried to identify possible disease causing microRNA(miRNA)-mRNA pairs (interactions) by analyzing (partially matched) miRNA/mRNA gene expression profiles with the recently proposed principal component analysis based unsupervised feature extraction. It successfully identified multiple miRNA-mRNA pairs whose biological natures are convincing. Correlation coefficients between miRNA and mRNA expression in matched parts of profiles turned out to be significantly negative. Constructed miRNA-mRNA network will be a key to understand Wilms tumor causing mechanisms.
RiVIERA-beta: Joint Bayesian inference of risk variants and tissue-specific epigenomic enrichments across multiple complex human diseases
Authors: Li Yue , Kellis Manolis
Published: June 2016

Genome wide association studies (GWAS) provide a powerful approach for uncovering disease-associated variants in human, but fine-mapping the causal variants remains a challenge. This is partly remedied by prioritization of disease-associated variants that overlap GWAS-enriched epigenomic annotations. Here, we introduce a new Bayesian model RiVIERA-beta (RiskVariantInference usingEpigenomicReferenceAnnotations) for inference of driver variants by modelling summary statistics p-values in Beta density function across multiple traits using hundreds of epigenomic annotations. In simulation, RiVIERA-beta promising power in detecting causal variants and causal annotations, the multi-trait joint inference further improved the detection power. We applied RiVIERA-beta to model the existing GWAS summary statistics of 9 autoimmune diseases and Schizophrenia by jointly harnessing the potential causal enrichments among 848 tissue-specific epigenomics annotations from ENCODE/Roadmap consortium covering 127 cell/tissue types and 8 major epigenomic marks. RiVIERA-beta identified meaningful tissue-specific enrichments for enhancer regions defined by H3K4me1 and H3K27ac for Blood T-Cell specifically in the 9 autoimmune diseases and Brain-specific enhancer activities exclusively in Schizophrenia. Moreover, the variants from the 95% credible sets exhibited high conservation and enrichments for GTEx whole-blood eQTLs located within transcription-factor-binding-sites and DNA-hypersensitive-sites. Furthermore, joint modeling the nine immune traits by simultaneously inferring and exploiting the underlying epigenomic correlation between traits further improved the functional enrichments compared to single-trait models.
A probabilistic framework to dissect functional cell-type-specific regulatory elements and risk loci underlying the genetics of complex traits
Authors: Li Yue , Davila-Velderrain Jose , Kellis Manolis
Published: June 2016

Dissecting the physiological circuitry underlying diverse human complex traits associated with heritable common mutations is an ongoing effort. The primary challenge involves identifying the relevant cell types and the causal variants among the vast majority of the associated mutations in the noncoding regions. To address this challenge, we developed an efficient probabilistic framework. First, we propose a sparse group-guided learning algorithm to infer cell-type-specific enrichments. Second, we propose a fine-mapping Bayesian model that incorporates as Bayesian priors the sparse enrichments to infer risk variants. Using the proposed framework to analyze 32 complex human traits revealed meaningful tissue-specific epigenomic enrichments indicative of the relevant disease pathologies. The prioritized variants exhibit prominent tissue-specific epigenomic signatures and significant enrichments for eQTL and conserved elements. Together, we demonstrate the general benefits of the proposed integrative framework in elucidating meaningful tissue-specific epigenomic elements from large-scale correlated annotations and the implicated functional variants for future experimental interrogation.
Auditory Nerve Stochasticity Impedes Auditory Category Learning: Learning: a Computational Account of the Role of Cochlear Nucleus and Inferior Colliculus in Stabilising Auditory Nerve Firing
Authors: Higgins Irina , Stringer Simon , Schnupp Jan
Published: June 2016

It is well known that auditory nerve (AN) fibers overcome bandwidth limitations through the “volley principle”, a form of multiplexing. What is less well known is that the volley principle introduces a degree of unpredictability into AN neural firing patterns which makes even simple stimulus categorization tasks difficult. We use a physiologically grounded, unsupervised spiking neural network model of the auditory brain with STDP learning to demonstrate that plastic auditory cortex is unable to learn even simple auditory object categories when exposed to the raw AN firing input without subcortical preprocessing. We then demonstrate the importance of non-plastic subcortical preprocessing within the cochlear nucleus (CN) and the inferior colliculus (IC) for stabilising and denoising AN responses. Such preprocessing enables the plastic auditory cortex to learn efficient robust representations of the auditory object categories. The biological realism of our model makes it suitable for generating neurophysiologically testable hypotheses.
The ciliary targeting of membrane proteins by a ternary complex comprising transportin1, Rab8 and the ciliary targeting signal
Authors: Madugula Viswanadh , Lu Lei
Published: June 2016

The sensory functions of cilia are dependent on the enrichment of ciliary resident proteins. While it is known that ciliary targeting signals (CTSs) specifically target ciliary proteins to cilia, it is still unclear how CTSs facilitate the entry and retention of ciliary residents at the molecular level. We found that non-ciliary membrane reporters can passively diffuse to cilia via the lateral transport pathway and the translocation of membrane reporters through the ciliary diffusion barrier is facilitated by importin binding motifs/domains. Screening known CTSs of ciliary membrane residents uncovered that fibrocystin, photoreceptor retinol dehydrogenase, rhodopsin and retinitis pigmentosa 2 interact with transportin1 (TNPO1) via previously identified CTSs. We further discovered that a novel ternary complex, comprising TNPO1, Rab8 and CTS, can assemble or disassemble under the guanine nucleotide exchange of Rab8. Our study suggests a novel mechanism in which TNPO1/Rab8/CTS complex mediates selective entry and retention of cargos within cilia.
Crystal structure of a one-dimensional looped-chain silver(I) coordination polymer:catena-poly[[silver(I)-bis{μ-4-[1-(5′-isopropyl-[1,1′:3′,1′′-terphenyl]-2′-yl)-1H-imidazol-2-yl]pyridine-κ2N:N′}] nitrate methanol monosolvate monohydrate]
Authors: Moon Suk-Hee , Park Ki-Min , Kang Youngjin
Published: June 2016

In the title compound, {[Ag(C29H25N3)2]NO3·CH3OH·H2O}n, the AgIcation is four-coordinated by two pyridine N atoms and two imidazole N atoms from four individual 4-(1-(5′-isopropyl-[1,1′:3′,1′′-terphenyl]-2′-yl)-1H-imidazol-2-yl)pyridine (i-pro-pyim) ligands. This gives rise to a highly distorted tetrahedral geometry with bond angles falling in the range 100.33 (19)–122.76 (19)°. Two crystallographically independenti-pro-pyim ligands (AandB) adopt very similar conformations to one another, such that the dihedral angles between the pyridyl and imidazolyl rings in the two ligands are 40.7 (3) and 42.2 (3)°, respectively. Eachi-pro-pyim ligand binds two symmetry-related Ag+cations, leading to the formation of 14-membered cyclic dimers, in which the AgIatoms are separated by 6.963 (2) Å for the Ag–A2–Ag dimer and 7.020 (2) Å for Ag–B2–Ag. These cyclic dimers are alternately connected to each other by sharing AgIatoms, resulting in the formation of a looped-chain structure extending along the [100] direction. Moreover, adjacent looped chains are connected by intermolecular π–π interactions [centroid-to-centroid distance = 3.689 (4) Å], giving rise to the formation of a two-dimensional supramolecular network propagating parallel to (110). Several intermolecular C—H...O and O—H...O hydrogen bonds further contribute to the stabilization of the crystal structure.
Multi-objective optimization of quarter car passive suspension design in the frequency domain based on PSO
Authors: Gomes Herbert Martins
Published: June 2016

Purpose

– The purpose of this paper is to investigate the optimum design of a quarter car passive suspension system using a particle swarm optimization algorithm in order to minimize the applied loads and vibrations.

Design/methodology/approach

– The road excitation is assumed as zero-mean random field and modeled by single-sided power spectral density (PSD) based on international standard ISO 8608. The variance of sprung mass displacements and variance of dynamic applied load are evaluated by PSD functions and used as cost function for the optimization.

Findings

– The advantages in using this methodology are emphasized by an example of the multi-objective optimization design of suspension parameters and the results are compared with values reported in the literature and other gradient based and heuristic algorithms. The paper shows that the algorithm effectively leads to reliable results for suspension parameters with low computational effort.

Research limitations/implications

– The procedure is applied to a quarter car passive suspension design.

Practical implications

– The proposed procedure implies substantial time savings due to frequency domain analysis.

Social implications

– The paper proposes a procedure that allows complex optimization designs to be feasible and cost effective.

Originality/value

– The design optimization is performed in the frequency domain taking into account standard defined road profiles PSD without the need to simulate in the time domain.
A new calculation method of casing external squeezing loads in complex formation
Authors: Yan Keju , Guan Zhichuan , Chen Hao , Zhao Xiaofeng , Zhang Hongning
Published: June 2016

Purpose

– Casing damage problems are increasingly prominent in oil fields, most of which were caused by casing external squeezing loads. The traditional calculation method of casing external squeezing loads is not very accurate now, especially in complex formation. The purpose of this paper is to propose a new calculation method to solve the problem of actual casing loads under above conditions.

Design/methodology/approach

– Based on Lame’s model of elastic mechanics, a new calculation method of casing external squeezing loads is deduced. Comprehensive influence laws of the loads which caused by in-situ stress, internal pressure, formation parameters, cement annulus parameters and casing parameters are analyzed.

Findings

– The paper provides a new calculation method of casing external squeezing loads, by which the dispersion effect of internal liquid pressure caused by casing wall material is eliminated. The main influence factors of casing external squeezing loads are in-situ stress and formation elastic modulus.

Research limitations/implications

– The model and boundary conditions used in the paper is based on elastic mechanics. The accuracy of the calculation results depends on the quality and accuracy of the input formation parameters.

Originality/value

– This paper proposes a new method to calculate casing external squeezing loads. And compared with traditional methods, this method is more practical.
Numerical simulation of Plateau’s problem of minimal surfaces using nonvariational finite element method
Authors: Mishra Garima , Kumar Manoj
Published: June 2016

Purpose

– Numerical solution of Plateau’s problem of minimal surface using non-variational finite element method. The paper aims to discuss this issue.

Design/methodology/approach

– An efficient algorithm is proposed for the computation of minimal surfaces and numerical results are presented.

Findings

– The solutions obtained here are examined for different cases of non-linearity and are found sufficiently accurate.

Originality/value

– The manuscript provide the non-variational solution for Plateau’s problem. Thus it has a good value in engineering application.
An algorithm for dynamic object manipulation by a flexible link robot
Authors: Tarvirdizadeh Bahram , Alipour Khalil , Hadi Alireza
Published: June 2016

Purpose

– The purpose of this paper is to focus on an online closed-loop (CL) approach for performing dynamic object manipulation (DOM) by a flexible link manipulator.

Design/methodology/approach

– Toward above goal, a neural network and optimal control are integrated in a closed-loop structure, to achieve a robust control for online DOM applications. Additionally, an elegant novel numerical solution method will be developed which can handle the split boundary value problem resulted from DOM mission requirements for a wide range of boundary conditions.

Findings

– The obtained simulation results reveal the effectiveness of both proposed innovative numerical solution technique and control structure for online object manipulation purposes using flexible manipulators.

Originality/value

– The object manipulation problem has previously been studied, however, for the first time its accomplishment by flexible link manipulators was addressed just in offline form considering an open-loop control structure (Tarvirdizadeh and Yousefi-Koma, 2012). As an extension of Tarvirdizadeh and Yousefi-Koma (2012), the current research, consequently, focusses on a numerical
solution and a CL approach for performing DOM by a flexible link manipulator.
A modified BLISCO method and its combination with variable fidelity metamodel for engineering design
Authors: Jiang Ping , Zhou Qi , Shao Xinyu , Long Ren , Zhou Hui
Published: June 2016

Purpose

– The purpose of this paper is to present a modified bi-level integrated system collaborative optimization (BLISCO) to avoid the non-separability of the original BLISCO. Besides, to mitigate the computational burden caused by expensive simulation codes and employ both efficiently simplified and expensively detailed information in multidisciplinary design optimization (MDO), an effective framework combining variable fidelity metamodels (VFM) and modified BLISCO (MBLISCO) (VFM-MBLISCO) is proposed.

Design/methodology/approach

– The concept of the quasi-separable MDO problems is introduced to limit range of applicability about the BLISCO method and then based on the quasi-separable MDO form, the modification of BLISCO method without any derivatives is presented to solve the problems of BLISCO. Besides, an effective framework combining VFM-MBLISCO is presented.

Findings

– One mathematical problem conforms to the quasi-separable MDO form is tested and the overall results illustrate the feasibility and robustness of the MBLISCO. The design of a Small Waterplane Area Twin Hull catamaran demonstrates that the proposed VFM-MBLISCO framework is a feasible and efficient design methodology in support of design of engineering products.

Practical implications

– The proposed approach exhibits great capability for MDO problems with tremendous computational costs.

Originality/value

– A MBLISCO is proposed which can avoid the non-separability of the original BLISCO and an effective framework combining VFM-MBLISCO is presented to efficiently integrate the different fidelities information in MDO.
AaramShop.com reinventing the e-grocery wheel in India
Authors: Rishi Bikramjit , Kapoor Ashish , Bhatia Sameer
Published: June 2016

Subject area

Marketing.

Study level/applicability

The courses in which this case can be used include e-business, e-commerce, digital marketing, retailing and marketing strategy. This case can be used to teach MBA students. This case is also having the equal relevance for the executive programmes.

Case overview

AaramShop is digitizing the Grocery General Trade ecosystem. There are of millions of neighbourhood kirana stores spread across all the cities of India. AaramShop is bringing these neighbourhood kirana stores online, and making them not only e-commerce-ready but also capable of using technology to take their stores to the next level in terms of service and delivery. The case lists out the issues and challenges faced by AaramShop.

Expected learning outcomes

This case challenges the participants to understand the new business model in the e-commerce space. The participants can look at the different angles of the business model proposition, namely, how AaramShop approach delivers on the retailer proposition, consumer proposition and the brands proposition. The participants can also be sensitized about the obstacles in making the business model more successful. These obstacles can be posed by the retailers, consumers or brands. The case will lead to a discussion about the logistics model opportunity available to Aaramshop.com.

Supplementary materials

Teaching notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

Subject code

CSS 8: Marketing
Frequent peer problems in Australian children and adolescents
Authors: Denham Renee , McGee Tara Renae , Eriksson Li , McGrath John , Norman Rosana , Sawyer Michael , Scott James
Published: June 2016

Purpose

– Whilst overt bullying has received considerable attention for its negative impact on the emotional well-being of children and adolescents, peer problems such as excessive teasing and social exclusion have received less consideration. The purpose of this paper is to examine the prevalence, demographic, and clinical correlates of frequent peer problems in children and adolescents who participated in the Australian National Survey of Mental Health and Well-Being.

Design/methodology/approach

– Participants were a nationally representative sample of 2,107 children (aged 6-12 years), and 1,490 adolescents (aged 13-17 years). Frequent peer problems (excessive teasing or social exclusion) were measured by parental report for children, and self and parental report for adolescents. Associations with a number of mental health problems were examined, including being in the clinical range for internalising and externalising symptoms, having major depressive disorder, attention deficit hyperactivity disorder or conduct disorder, low self-esteem, experiencing suicidal ideation and behaviour, or using marijuana and alcohol.

Findings

– One in 30 children and one in 20 adolescents experienced frequent peer problems. Parents less commonly identified frequent peer problems than were self-reported by their adolescent children. Frequent peer problems were strongly associated with all mental health problems except alcohol and marijuana use.

Originality/value

– Frequent peer problems are associated with a greatly increased risk of mental health problems. Identifying those children and adolescents with frequent peer problems provides opportunity for assessment and intervention of emotional and behavioural problems.
A critique on accounting for murabaha contract
Authors: Ahmed Mezbah Uddin , Sabirzyanov Ruslan , Rosman Romzie
Published: June 2016

Purpose

The purpose of this paper is to examine the accounting treatment and reporting of a murabaha contract and its implication to the financial statements of Islamic banks. In addition, the paper also explains the implication of time value of money on the measurement of a murabaha contract and the concept of substance over form in recognising financial transactions.

Design/methodology/approach

This study reviews the accounting treatment and reporting for a murabaha contract as stated in the Financial Accounting Standards (FAS) of the Accounting and Auditing Organization for Islamic Financial Institutions (AAOIFI) and the application of a murabaha contract as a financial instrument based on International Financial Reporting Standards (IFRS).

Findings

The paper finds that, while IFRS-based financial reporting primarily focuses on economic consequences of financial instruments, AAOIFI further takes into consideration the legal structure of the instruments, which are based on Shari’ah precepts. The paper also finds that IFRS-based financial reporting cannot always capture the distinctive structure of the murabaha and, hence, may lack representational financial reporting. However, the IFRS recognizes the substance of a murabaha contract as financing, and the majority of Islamic banks in Malaysia report it as one of financing and not as a trading contract. For measurement, IFRS adopted the concept of time value of money where the profit allocation is based on amortized cost, which is similar to the measurement of conventional loan transactions that apply the concept of effective interest rate. Meanwhile, AAOIFI uses a straight-line basis to allocate the profit of a murabaha contract.

Practical implications

The forthright discussion and the observations of the paper are expected to assist regulators and standard setters in developing accounting standards that are in convergence but also cater to the unique characteristics of Islamic financial transactions.

Originality/value

The paper criticizes both accounting treatment of a murabaha contract based on the AAOIFI and IFRS and then suggests an extension of these treatments to be adopted to improve the reporting.
Cross country co-movement in equity markets after the US financial crisis
Authors: Singh Amanjot , Singh Manjit
Published: June 2016

Purpose

This paper aims to attempt to capture the co-movement of the Indian equity market with some of the major economic giants such as the USA, Europe, Japan and China after the occurrence of global financial crisis in a multivariate framework. Apart from these cross-country co-movements, the study also captures an intertemporal risk-return relationship in the Indian equity market, considering the covariance of the Indian equity market with the other countries as well.

Design/methodology/approach

To account for dynamic correlation coefficients and risk-return dynamics, vector autoregressive (1) dynamic conditional correlation–asymmetric generalized autoregressive conditional heteroskedastic model in a multivariate framework and exponential generalized autoregressive conditional heteroskedastic model in mean with covariances as explanatory variables are used. For an in-depth analysis, Markov regime switching model and optimal hedging ratios and weights are also computed. The span of data ranges from August 10, 2010 to August 7, 2015, especially after the global financial crisis.

Findings

The Indian equity market is not completely decoupled from mature markets as well as emerging market (China), but the time-varying correlation coefficients are on a downward spree after the global financial crisis, except for the US market. The Indian and Chinese equity markets witness a highest level of correlation with each other, followed by the European, US and Japanese markets. Both the optimal portfolio hedge ratios and portfolio weights with two asset classes point out toward portfolio risk minimization through the combination of the Indian and US equity market stocks from a US investor viewpoint. A negative co-movement between the Indian and US market increases the conditional expected returns in the Indian equity market. There is an insignificant but a negative relationship between the expected risk and returns.

Practical implications

The study provides an insight to the international as well as domestic investors and supports the construction of cross-country portfolios and risk management especially after the occurrence of global financial crisis.

Originality/value

The present study contributes to the literature in three senses. First, the period relates to the events after the global financial crisis (2007-2009). Second, the study examines the co-movement of the Indian equity market with four major economic giants such as the USA, Europe, Japan and China in a multivariate framework. These economic giants are excessively following the easy money policies aftermath the financial crisis so as to wriggle out of deflationary phases. Finally, the study captures risk-return relationship in the Indian equity market, considering its covariance with the international markets.
Visualization techniques supporting performance measurement system development
Authors: Jääskeläinen Aki , Roitto Juho-Matias
Published: June 2016

Purpose

This paper aims to understand how performance measurement system development process can be supported by visualization techniques. It analyses the suitability of different visualization techniques in the tasks needed in designing, implementing and using performance measurement.

Design/methodology/approach

The research builds upon literature review and analysis. The empirical access to five recent performance measurement system development projects is also used to evaluate the applicability of visualization techniques. The emphasis is in information visualization, and the following techniques are examined: maps, diagrams, networks, visualized models, graphs, charts and dashboards.

Findings

The study provides a concise overview on visualization techniques highlighting the managerial tasks related to performance measurement system development process. It contributes as a discussion opener inviting more academicians to study the topic of visualization in management and to further test and broaden the proposals presented in the paper.

Research limitations/implications

Further in-depth empirical research is needed regarding each phase of performance measurement development process. A further study could also stress more the proactive use of performance measurement paying attention also to the external environment.

Practical implications

The topic of information visualization is practically driven. The results support practitioners in evaluating and choosing visualization techniques supporting their timely challenges in the performance measurement development.

Originality/value

Few studies on information visualization have been carried out in the context of management science. Visualization can integrate human in the data exploration process and improve understanding over large data sets without complex quantitative methods. Visualization techniques have been proposed as powerful means to enhance the effectiveness of performance measurement. This study structures and clarifies the ambiguous topic of visualization and performance management and suggests areas for further research.
The drivers of profitability in the top 30 major airlines worldwide
Authors: Lopes Ilídio Tomás , Ferraz Duarte Pitta , Rodrigues Ana Maria Gomes
Published: June 2016

Purpose

The purpose of this study is to identify the impact of human and structural capital on profitability of major airlines and examine whether region, capital ownership and control and strategic alliance play a clustering effect on profitability.

Design/methodology/approach

Using information from the top 30 airlines worldwide, in particular human and structural capital proxies, a linear model is regressed. Test of hypotheses were performed towards the identification of the influence emerged from variables, such as region, capital ownership and control and strategic alliances, on intellectual capital drivers and profitability.

Findings

Turnover is driven by human and structural capital factors, namely: employee expenses and benefits; size of board of directors; intangible assets; codeshare agreements; and passenger traffic. Airlines profitability does not depend on region, capital ownership and control or strategic alliance in which the company is integrated.

Research limitations/implications

In spite of the limitations, we underline the range of time under analysis and the sample size. However, the current approach can be replicated over time and based in other rankings, structured on different metrics and approaches.

Practical implications

The empirical results provide both an understanding of how independent variables positively affect the performance of airlines and offer some explanation as to the relationship between key characteristics of firms and profitability.

Originality/value

The research adds value to the current literature by exploring the effects of new intellectual capital drivers on profitability of airlines firms. Focused on a sector that strongly contributes to improve the networking between nations, it provides a new and updated overview.