bluuebunny/crossref_metadata_2025 huggingface dataset:
Detailed Study on Stiffness and Load Characteristics of Film-Riding Groove Types Using Design of Experiments
Authors: Tibos S. M. , Georgakis C. , Harvey K. , Teixeira J. A.
Published: April 2017

In the application of film-riding sealing technology, there are various groove features that can be used to induce hydrodynamic lift. However, there is little guidance in selecting the relative parameter settings in order to maximize hydrodynamic load and fluid stiffness. In this study, two groove types are investigated—Rayleigh step and inclined groove. The study uses a design of experiments approach and a Reynolds equation solver to explore the design space. Key parameters have been identified that can be used to optimize a seal design. The results indicate that the relationship between parameters is not a simple linear relationship. It was also found that higher pressure drops hinder the hydrodynamic load and stiffness of the seal suggesting an advantage for using hydrostatic load support in such conditions.
Aerothermal Performance of a Nozzle Vane Cascade With a Generic Nonuniform Inlet Flow Condition—Part II: Influence of Purge and Film Cooling Injection
Authors: Barigozzi G. , Abdeh H. , Perdichizzi A. , Henze M. , Krueckels J.
Published: April 2017

In the present paper, the influence of the presence of an inlet flow nonuniformity on the aerodynamic and thermal performance of a film cooled linear nozzle vane cascade is fully assessed. Tests have been carried out with platform cooling, with coolant ejected through a slot located upstream of the leading edge. Cooling air is also ejected through a row of cylindrical holes located upstream of the slot, simulating a combustor cooling system. An obstruction was installed upstream of the cascade at variable tangential and axial position to generate a flow nonuniformity. The cascade was tested at a high inlet turbulence intensity level (Tu1 = 9%) and at a constant inlet Mach number of 0.12 and nominal cooling condition. Aerothermal characterization of vane platform was obtained through five-hole probe and end wall adiabatic film cooling effectiveness measurements. Results show a relevant negative impact of inlet flow nonuniformity on the cooled cascade aerodynamic and thermal performance. Higher film cooling effectiveness and lower aerodynamic losses are obtained when the inlet flow nonuniformity is located at midpitch, while lower effectiveness and higher losses are obtained when it is aligned to the vane leading edge. Moving the nonuniformity axially or changing its blockage only marginally influences the platform thermal protection.
Achieving Ultra-Omniphilic Wettability on Copper Using a Facile, Scalable, Tuned Bulk Micromanufacturing Approach
Authors: Clegg Nicholas , Kota Krishna , He Xin , Ross Sean
Published: April 2017

Altering the wetting characteristics of copper will positively impact numerous practical applications. The contact angle (CA) of a water droplet on the polished copper surface is usually between 70 deg and 80 deg. This paper discusses a facile, scalable, tuned bulk micromanufacturing approach for altering the surface topology of copper concomitantly at the micro- and nano-length scales, and thus significantly influence its wetting characteristics. The resultant copper surfaces were found to be robust, nontoxic, and exhibited ultra-omniphilicity to various industrial liquids. This extreme wetting ability akin to a paper towel (CA of zero for multiple liquids) was achieved by tuning the bulk micromanufacturing process to generate connected hierarchical micro- and nano-roughness with nanocavities within the embryos of microcavities. With an adsorbed coating of ester, the same ultra-omniphilic copper surfaces were found to exhibit robust super-hydrophobicity (CA ∼ 152 deg for water).
Effects of Vanadium Oxide Nanoparticles on Friction and Wear Reduction
Authors: Dai Wei , Lee Kyungjun , Sinyukov Alexander M. , Liang Hong
Published: April 2017

In this research, rheological and tribological performance of additive V2O5 nanoparticles in a light mineral oil has been investigated. For rheological performance, the addition of 0.2 wt. % V2O5 could reduce the viscosity of the base oil for 6%. Considering the overall friction reduction in boundary, mixed, and hydrodynamic lubrication regimes, that with 0.1 wt. % V2O5 exhibited the best effect. Friction coefficient of base oil could be reduced by 33%. In terms of wear, the addition of 0.2 wt. % V2O5 showed the lowest wear rate, which is 44% reduction compared to base oil. Through Raman spectrum and energy dispersive spectroscopy (EDS) analysis, it was found that V2O5 involved tribochemical reaction during rubbing. Vanadium intermetallic alloy (V–Fe–Cr) was found to enhance the antiwear performance. This research revealed that V2O5 nanoparticles could be an effective additive to improve tribological performance.
Infants adapt to speaking rate differences in word segmentation
Authors: Wang Yuanyuan , Llanos Fernando , Seidl Amanda
Published: April 2017

Throughout their development, infants are exposed to varying speaking rates. Thus, it is important to determine whether they are able to adapt to speech at varying rates and recognize target words from continuous speech despite speaking rate differences. To address this question, a series of four experiments were conducted to test whether infants can recognize words in continuous speech when rate is variable. In addition, the underlying mechanisms that infants may use to cope with variations induced by different speaking rates were also examined. Specifically, using the Headturn Preference procedure [Jusczyk and Aslin (1995). Cognitive Psychol. 29, 1–23], infants were familiarized with normal-rate passages containing two trisyllabic target words (e.g., elephants and dinosaurs), and tested with familiar (elephants and dinosaurs) and unfamiliar (crocodiles and platypus) words embedded in normal-rate (experiment 1), fast-rate (experiments 2 and 3), or slow-rate passages (experiment 4). The results indicate that 14-month-olds, but not 11-month-olds, recognized target words in passages with a fast speaking rate. In addition, findings suggest that infants used context to normalize speech across different speaking rates.
Becoming a Sport Psychologist Employed by a University Athletic Department
Authors: Johnson Michael B.
Published: April 2017

The primary purpose of the current article is to supply those who wish to attain employment as a sport psychologist within a university athletic department (SPAD) with relevant information. The content herein describes one clinician’s path to becoming a SPAD, from undergraduate education to current-day work. The author often receives requests (between six and ten a year) from aspiring sport psychologists for information on how he attained his position. The current article begins with a concise presentation of the author’s background. This is followed by a brief overview of his current work. What follows are succinct recommendations for those who seek similar positions, including thoughts on (a) training, (b) the idiosyncratic personality-work environment fit, and (c) developing efficacious interpersonal relationships with those responsible for hiring such positions.
Transitioning Out of Professional Sport: The Psychosocial Impact of Career-Ending Injuries Among Elite Irish Rugby Football Union Players
Authors: Arvinen-Barrow Monna , Hurley Diarmuid , Ruiz Montse C.
Published: April 2017

This study documented the lived career-ending injury experiences among elite Irish rugby football union (IRFU) players. Three players took part in semistructured one-on-one interviews. Interpretative phenomenological analysis (Smith, 1996) revealed that the process of psychosocial injury rehabilitation and the subsequent transition process was for the most part a distressing one and evolved in a cyclical, yet stage-like (Heil, 1994), manner. The nature of the postinjury career transition appeared to be dependent on the interactional balance of participants’ psychosocial responses to injury, existing coping mechanisms, and other factors related to the injury and career transition process. Appropriate social support network, use of sport medicine and counseling professionals, as well as organizational officials are needed to best prepare elite rugby players for life outside of sport, and to ensure a healthy career transition (Taylor & Ogilvie, 1994) out of sport.
The transcription factor MAFK induces EMT and malignant progression of triple-negative breast cancer cells through its target GPNMB
Authors: Okita Yukari , Kimura Minori , Xie Rudy , Chen Chen , Shen Larina Tzu-Wei , Kojima Yurika , Suzuki Hiroyuki , Muratani Masafumi , Saitoh Masao , Semba Kentaro , Heldin Carl-Henrik , Kato Mitsuyasu
Published: April 2017

Inhibiting the activity of the transcription factor MAFK may suppress the progression of triple-negative breast cancer.
Papers of note in
Science Translational Medicine
9
(384)
Authors: Ferrarelli Leslie K.
Published: April 2017

This week’s articles reveal how drugs that prime the tumor stroma can enhance chemotherapy and how disrupting select chemokine interactions might treat inflammatory disease.
Structural Insights into HIV Reverse Transcriptase Mutations Q151M and Q151M Complex That Confer Multinucleoside Drug Resistance
Authors: Das Kalyan , Martinez Sergio E. , Arnold Eddy
Published: April 2017

HIV-1 reverse transcriptase (RT) is targeted by multiple drugs. RT mutations that confer resistance to nucleoside RT inhibitors (NRTIs) emerge during clinical use. Q151M and four associated mutations, A62V, V75I, F77L, and F116Y, were detected in patients failing therapies with dideoxynucleosides (didanosine [ddI], zalcitabine [ddC]) and/or zidovudine (AZT). The cluster of the five mutations is referred to as the Q151M complex (Q151Mc), and an RT or virus containing Q151Mc exhibits resistance to multiple NRTIs. To understand the structural basis for Q151M and Q151Mc resistance, we systematically determined the crystal structures of the wild-type RT/double-stranded DNA (dsDNA)/dATP (complex I), wild-type RT/dsDNA/ddATP (complex II), Q151M RT/dsDNA/dATP (complex III), Q151Mc RT/dsDNA/dATP (complex IV), and Q151Mc RT/dsDNA/ddATP (complex V) ternary complexes. The structures revealed that the deoxyribose rings of dATP and ddATP have 3′-endo and 3′-exo conformations, respectively. The single mutation Q151M introduces conformational perturbation at the deoxynucleoside triphosphate (dNTP)-binding pocket, and the mutated pocket may exist in multiple conformations. The compensatory set of mutations in Q151Mc, particularly F116Y, restricts the side chain flexibility of M151 and helps restore the DNA polymerization efficiency of the enzyme. The altered dNTP-binding pocket in Q151Mc RT has the Q151-R72 hydrogen bond removed and has a switched conformation for the key conserved residue R72 compared to that in wild-type RT. On the basis of a modeled structure of hepatitis B virus (HBV) polymerase, the residues R72, Y116, M151, and M184 in Q151Mc HIV-1 RT are conserved in wild-type HBV polymerase as residues R41, Y89, M171, and M204, respectively; functionally, both Q151Mc HIV-1 and wild-type HBV are resistant to dideoxynucleoside analogs.
Synthetic (p)ppGpp Analogue Is an Inhibitor of Stringent Response in Mycobacteria
Authors: Syal Kirtimaan , Flentie Kelly , Bhardwaj Neerupma , Maiti Krishnagopal , Jayaraman Narayanaswamy , Stallings Christina L. , Chatterji Dipankar
Published: April 2017

Bacteria elicit an adaptive response against hostile conditions such as starvation and other kinds of stresses. Their ability to survive such conditions depends, in part, on stringent response pathways. (p)ppGpp, considered to be the master regulator of the stringent response, is a novel target for inhibiting the survival of bacteria. In mycobacteria, the (p)ppGpp synthetase activity of bifunctional Rel is critical for stress response and persistence inside a host. Our aim was to design an inhibitor of (p)ppGpp synthesis, monitor its efficiency using enzyme kinetics, and assess its phenotypic effects in mycobacteria. As such, new sets of inhibitors targeting (p)ppGpp synthesis were synthesized and characterized by mass spectrometry and nuclear magnetic resonance spectroscopy. We observed significant inhibition of (p)ppGpp synthesis by Rel
Msm
in the presence of designed inhibitors in a dose-dependent manner, which we further confirmed by monitoring the enzyme kinetics. The Rel enzyme inhibitor binding kinetics were investigated by isothermal titration calorimetry. Subsequently, the effects of the compounds on long-term persistence, biofilm formation, and biofilm disruption were assayed in
Mycobacterium smegmatis
, where inhibition in each case was observed.
In vivo
, (p)ppGpp levels were found to be downregulated in
M. smegmatis
treated with the synthetic inhibitors. The compounds reported here also inhibited biofilm formation by the pathogen
Mycobacterium tuberculosis
. The compounds were tested for toxicity by using an MTT assay with H460 cells and a hemolysis assay with human red blood cells, for which they were found to be nontoxic. The permeability of compounds across the cell membrane of human lung epithelial cells was also confirmed by mass spectrometry.
Specific
bla
CTX-M-8
/IncI1 Plasmid Transfer among Genetically Diverse Escherichia coli Isolates between Humans and Chickens
Authors: Norizuki Chihiro , Wachino Jun-ichi , Suzuki Masahiro , Kawamura Kumiko , Nagano Noriyuki , Kimura Kouji , Arakawa Yoshichika
Published: April 2017

We investigated the genetic backbones of 14
bla
CTX-M-8
-positive
Escherichia coli
isolates recovered from human stool samples and chicken meat. All isolates carried IncI1 plasmids with
bla
CTX-M-8
(
bla
CTX-M-8
/IncI1), and most (9/14) belonged to a specific genetic lineage, namely, plasmid sequence type 113 (pST113). The genetic contexts of the nine
bla
CTX-M-8
/IncI1 pST113 plasmids were similar, regardless of the source. These results suggest the probable local transfer of
bla
CTX-M-8
/IncI1 between humans and chickens with genetically diverse
E. coli
.
Highly Tigecycline-Resistant Klebsiella pneumoniae Sequence Type 11 (ST11) and ST147 Isolates from Companion Animals
Authors: Ovejero Cristina M. , Escudero Jose Antonio , Thomas-Lopez Daniel , Hoefer Andreas , Moyano Gabriel , Montero Natalia , Martin-Espada Carmen , Gonzalez-Zorn Bruno
Published: April 2017

In this study, we characterized two tigecycline-resistant
Klebsiella pneumoniae
isolates from dog urine samples. The isolates were genetically unrelated, belonging to sequence type 11 (ST11) and ST147, both classically related to human isolates. To the best of our knowledge, this is the first identification of tigecycline-resistant isolates from animals. We unveil here the worrisome circulation among animals of bacterial clones resistant to this last-resort antibiotic.
Giardia Alters Commensal Microbial Diversity throughout the Murine Gut
Authors: Barash N. R. , Maloney J. G. , Singer S. M. , Dawson S. C.
Published: April 2017

Giardia lamblia
is the most frequently identified protozoan cause of intestinal infection. Over 200 million people are estimated to have acute or chronic giardiasis, with infection rates approaching 90% in areas where
Giardia
is endemic. Despite its significance in global health, the mechanisms of pathogenesis associated with giardiasis remain unclear, as the parasite neither produces a known toxin nor induces a robust inflammatory response.
Giardia
colonization and proliferation in the small intestine of the host may, however, disrupt the ecological homeostasis of gastrointestinal commensal microbes and contribute to diarrheal disease associated with giardiasis. To evaluate the impact of
Giardia
infection on the host microbiota, we used culture-independent methods to quantify shifts in the diversity of commensal microbes throughout the gastrointestinal tract in mice infected with
Giardia
. We discovered that
Giardia
's colonization of the small intestine causes a systemic dysbiosis of aerobic and anaerobic commensal bacteria. Specifically,
Giardia
colonization is typified by both expansions in aerobic
Proteobacteria
and decreases in anaerobic
Firmicutes
and
Melainabacteria
in the murine foregut and hindgut. Based on these shifts, we created a quantitative index of murine
Giardia
-induced microbial dysbiosis. This index increased at all gut regions during the duration of infection, including both the proximal small intestine and the colon. Giardiasis could be an ecological disease, and the observed dysbiosis may be mediated directly via the parasite's unique anaerobic fermentative metabolism or indirectly via parasite induction of gut inflammation. This systemic alteration of murine gut commensal diversity may be the cause or the consequence of inflammatory and metabolic changes throughout the gut. Shifts in the commensal microbiota may explain observed variations in giardiasis between hosts with respect to host pathology, degree of parasite colonization, infection initiation, and eventual clearance.
Transperineal aggressive angiomyxoma
Authors: Pereira Pedro , Melo Abreu Elisa , Cunha Teresa Margarida , Rolim Inês
Published: April 2017

A 45-year-old woman with a history of total hysterectomy with adnexal preservation for uterine leiomyomas presented to our hospital with a right gluteal palpable mass, which she first noticed 6 months before and had progressively enlarged since then.

Radiological studies revealed a 14 cm lesion with translevator growth that displaced rather than invaded adjacent structures, with a peculiar whorled pattern on T2-weighted MRI, which enhanced following gadolinium administration. CT-guided biopsy was performed, and in conjunction with imaging features the diagnosis of an aggressive angiomyxoma was assumed and confirmed following surgical excision.
Predictors and clinical implication of high-sensitivity cardiac troponin-I elevation following diagnostic cardiac catheterisations
Authors: Hamaya Rikuta , Yonetsu Taishi , Murai Tadashi , Kanaji Yoshihisa , Usui Eisuke , Matsuda Junji , Hoshino Masahiro , Araki Makoto , Hada Masahiro , Niida Takayuki , Ichijo Sadamitsu , Kanno Yoshinori , Kakuta Tsunekazu
Published: April 2017

Objectives

Although diagnostic coronary angiography (CAG) is performed worldwide, procedure-related myocardial necrosis (PMN) following diagnostic catheter-based procedures has not been well investigated. The aim of this study was to determine clinical and procedural factors associated with PMN, using a high-sensitivity cardiac troponin I (hs-cTnI) assay, and to investigate the clinical implications of PMN.

Methods

Among 697 patients undergoing elective CAG and pre- and post-procedural hs-cTnI (pre-TnI, post-TnI, respectively) measurements, a total of 538 patients (124 female) were evaluated, with 2.2% lost during follow-up. Minor PMN was defined as post-TnI above the sex-specific upper reference limit (URL), with a 20% increase from the pre-TnI level. Major PMN was defined as post-TnI above 5x the URL. Clinical and procedural factors predicting PMN and the association between PMN and major adverse cardiac events (MACE) following CAG were examined.

Results

PMN of any type was detected in 178 patients (33.0%), while major PMN was observed in 32 patients (5.9%). Female sex, estimated glomerular filtration rate, procedural time, left ventricular end-diastolic pressure (LVEDP) and fractional flow reserve measurement independently predicted any PMN; whereas, only LVEDP and log-transformed N-terminal pro-brain natriuretic peptide independently predicted major PMN. The incidence of MACE was significantly associated with major PMN. Cox proportional-hazards models revealed that major PMN, pre-TnI, and the absence of statin use were independently associated with MACE.

Conclusions

Diagnostic cardiac catheteriation may highlight cardiomyocyte susceptibility to stress in patients with or without CAD. CAG-related major myocardial injury might be associated with future adverse cardiac events independently of the presence or absence of functional stenosis.
Does intensified boreal forest harvesting impact soil microbial community structure and function?
Authors: Smenderovac Emily E. , Webster Kara , Caspersen John , Morris Dave , Hazlett Paul , Basiliko Nathan
Published: April 2017

Intensified biomass harvesting in northern forests could potentially negatively impact soils. This study measured microbial community structure and function to assess the impacts of intensified biomass removal on soil from a managed northern jack pine (Pinus banksiana Lamb.) forest in Ontario, Canada. Four clear-cut harvesting removal intensities were compared with uncut controls and mature, fire-regenerated forest reference plots: stem-only removal, full-tree biomass removal, full-tree biomass with stump removal, and full-tree biomass with stump removal and soil blading that eliminated all aboveground and much belowground organic matter. A nearby recently burned forest site, representing common natural disturbance in the region, was also studied. Within the first two years after harvesting, there were significant differences in community structure and degradation of various C compounds among all harvested and unharvested sites, but little difference in communities across the different harvest intensities. Communities within the fire site were not comparable with those of harvested treatments, indicating that clear-cut logging may not initially produce an ecologically comparable disturbance with that of fire, although this conclusion is based on only one fire disturbance site. In the two years after harvesting, an important time for seedling establishment in managed forest systems, it appears that intensification of harvesting does not further disrupt microbial community structure and functioning beyond impacts from current harvest practices.
Dark matter model from the idea of multi-cohesive areas
Authors: Chojnowski Maciej
Published: April 2017

This work presents a dark matter (DM) model from the idea of multi-cohesive areas (MCA). We introduce the main MCA’s DM features and put them into the context of current experiments on the DM phenomena. By doing so, we determine new ways of exploring the so-far mysterious DM world. Finally, we show motivations and indication for the further MCA development.
Quantum signature of breathers in 1D ultracold bosons in optical lattices involving next-nearest neighbor interactions
Authors: Djoufack Z. I. , Kenfack-Jiotsa A. , Nguenang J.-P.
Published: April 2017

The dynamics and the energy spectrum of an ultracold gas of bosonic atoms in an optical lattice can be described by a Bose–Hubbard model for which the system parameters can be controlled by laser light. We study by means of the perturbation theory in addition to the numerical diagonalization, the energy spectrum and the related features of the band structures of the ultracold bosons in optical lattices containing a few number of quanta interacting with next-nearest neighbor interactions (NNNI) modeled by the Bose–Hubbard Hamiltonian. The energy spectra of such system display the bound states signature, which are analyzed in the first Brillouin zone for different wave numbers. The finding, i.e., quantum breathers, shows that their probabilities’ weight depends on the wave vector. The influence of NNNI on both the probabilities’ amplitude and the correlation function is also realized in case of a system with a small number of sites, respectively.
Theoretical analysis of a hybrid traffic model accounting for safe velocity
Authors: Wang Yu-Qing , Zhou Chao-Fan , Yan Bo-Wen , Zhang De-Chen , Wang Ji-Xin , Jia Bin , Gao Zi-You , Wu Qing-Song
Published: April 2017

A hybrid traffic-flow model [Wang–Zhou–Yan (WZY) model] is brought out in this paper. In WZY model, the global equilibrium velocity is replaced by the local equilibrium one, which emphasizes that the modification of vehicle velocity is based on the view of safe-driving rather than the global deployment. In the view of safe-driving, the effect of drivers’ estimation is taken into account. Moreover, the linear stability of the traffic model has been performed. Furthermore, in order to test the robustness of the system, the evolvement of the density wave and the velocity wave of the traffic flow has been numerically calculated.
Security of a control key in quantum key distribution
Authors: ur Rehman Junaid , Qaisar Saad , Jeong Youngmin , Shin Hyundong
Published: April 2017

Quantum key distribution (QKD) schemes rely on the randomness to exchange secret keys between two parties. A control key to generate the same (pseudo)-randomness for the key exchanging parties increases the key exchange rate. However, the use of pseudo-randomness where true randomness is required makes a classical system vulnerable to the known plain-text attack. Contrary to the belief of unavailability of this attack in QKD, we show that this attack is actually possible whenever a control key is employed. In this paper, we show that it is possible to make use of the uncertainty principle to not only avoid this attack, but also remove the hazards of photon-number splitting attack in quantum setting. We define the secrecy of control key based on the guessing probability, and propose a scheme to achieve this defined secrecy. We show the general applicability of our framework on the most common QKD schemes.
Rényi entropy for particle systems as an instrument to enlarge the Boltzmannian concept of entropy: Some holographic perspectives
Authors: Masi Nicolò
Published: April 2017

The Rényi entropy is a mathematical generalization of the concept of entropy and it encodes the total information of a system as a function of its order parameter [Formula: see text]. The meaning of the Rényi entropy in physics is not completely established. Here we determined a general and explicit representation of the Rényi entropy for whichever fluid of particles and spin-statistics in the mechanical statistics framework. This allowed us to put physical constraints to the Rényi order [Formula: see text], from main thermodynamic relations and entropy bounds of the holographic theories, defining how much we can enlarge the Boltzmannian concept of entropy.
Cosmological inflation in a generalized unimodular gravity
Authors: Nozari K. , Shafizadeh S.
Published: April 2017

We study some aspects of cosmological inflation in the framework of unimodular [Formula: see text] gravity. To be more clearer, we consider a generic [Formula: see text] of the type [Formula: see text]. By considering the Einstein frame counterpart of the unimodular [Formula: see text] gravity, we set the scalaron to be responsible for cosmological inflation in this setup. We confront our model parameters space with observational data and impose some constraints on the value of [Formula: see text] in this manner. We show that for the number of [Formula: see text]-folds [Formula: see text], the model is consistent with observation if [Formula: see text].
EFFECTS OF PROCESS PARAMETERS AND CRYOTREATED ELECTRODE ON THE RADIAL OVERCUT OF AISI 304 IN SiC POWDER MIXED EDM
Authors: BHAUMIK MUNMUN , MAITY KALIPADA
Published: April 2017

Powder mixed electro discharge machining (PMEDM) is further advancement of conventional electro discharge machining (EDM) where the powder particles are suspended in the dielectric medium to enhance the machining rate as well as surface finish. Cryogenic treatment is introduced in this process for improving the tool life and cutting tool properties. In the present investigation, the characterization of the cryotreated tempered electrode was performed. An attempt has been made to study the effect of cryotreated double tempered electrode on the radial overcut (ROC) when SiC powder is mixed in the kerosene dielectric during electro discharge machining of AISI 304. The process performance has been evaluated by means of ROC when peak current, pulse on time, gap voltage, duty cycle and powder concentration are considered as process parameters and machining is performed by using tungsten carbide electrodes (untreated and double tempered electrodes). A regression analysis was performed to correlate the data between the response and the process parameters. Microstructural analysis was carried out on the machined surfaces. Least radial overcut was observed for conventional EDM as compared to powder mixed EDM. Cryotreated double tempered electrode significantly reduced the radial overcut than untreated electrode.
Adaptation of Telegraph Diffusion Equation for Noise Reduction on Images
Authors: Ghislain Pandry Koffi , Loum Georges Lausanne , Nouho Ouattara
Published: April 2017

The Telegraph Diffusion Equation (TDE) used in some noise reduction processes in an image includes two main parameters: the damping coefficient and the relaxation time. Classically, the first is determined globally for a given input image, while the second one is set constant. In this paper, we propose to determine the values of these parameters according to the information and the image local structure. We then get an adaptive diffusion equation that permits to better control the degree of smoothness and preserve fine structures and image contours avoiding speckles phenomena and staircase. The acquired results show that the proposed method improves the quality of images that have a weak signal-to-noise ratio, comparatively to the methods based on the TDE whose parameters are not adaptive.
Learning rates for regularized least squares ranking algorithm
Authors: Zhao Yulong , Fan Jun , Shi Lei
Published: April 2017

The ranking problem aims at learning real-valued functions to order instances, which has attracted great interest in statistical learning theory. In this paper, we consider the regularized least squares ranking algorithm within the framework of reproducing kernel Hilbert space. In particular, we focus on analysis of the generalization error for this ranking algorithm, and improve the existing learning rates by virtue of an error decomposition technique from regression and Hoeffding’s decomposition for U-statistics.
Convergent expansions of the incomplete gamma functions in terms of elementary functions
Authors: Bujanda Blanca , López José L. , Pagola Pedro J.
Published: April 2017

We consider the incomplete gamma function [Formula: see text] for [Formula: see text] and [Formula: see text]. We derive several convergent expansions of [Formula: see text] in terms of exponentials and rational functions of [Formula: see text] that hold uniformly in [Formula: see text] with [Formula: see text] bounded from below. These expansions, multiplied by [Formula: see text], are expansions of [Formula: see text] uniformly convergent in [Formula: see text] with [Formula: see text] bounded from above. The expansions are accompanied by realistic error bounds.
An intrinsic formulation of the Kirchhoff–Love theory of linearly elastic plates
Authors: Ciarlet Philippe G. , Mardare Cristinel
Published: April 2017

We recast the displacement-traction problem of the Kirchhoff–Love theory of linearly elastic plates as a boundary value problem with the bending moments and stress resultants inside the middle section of the plate as the sole unknowns, instead of the displacement field in the classical formulation. To this end, we show in particular how to recast the Dirichlet boundary conditions satisfied by the displacement field of the middle surface of a plate as boundary conditions satisfied by the bending moments and stress resultants.
Living Lab as an Approach to Activate Dynamic Innovation Ecosystems and Networks: An Empirical Study
Authors: Del Vecchio Pasquale , Elia Gianluca , Ndou Valentina , Secundo Giustina , Specchia Fabrizio
Published: April 2017

This paper aims to discuss the importance of Living Labs as an effective mechanism that can support the creation of dynamic innovation ecosystems and networks. The analysis of literature related to regional innovation and based on the Quadruple Helix framework, is integrated with exploratory research analysis of 20 cases of Italian Living Labs. The field study is realized through a web-based content analysis and questionnaires. The paper contributes to study how the Living Lab can constitute an effective mechanism supporting the creation of dynamic innovation ecosystems and networks, in the final aim to explore its relevance for setting regional strategies for smart growth, which valorize the internal and external knowledge assets. The paper provides important implications, both at research and policy levels, related with the knowledge-based innovation processes that could be activated at territorial level.
On generalizations of certain nonlinear integral inequalities and their applications
Authors: Latpate S. G.
Published: April 2017

The aim of this paper is to generalize some integral inequalities of Gronwall–Bellman type. We generalize the results presented by Pachpatte in [Inequalities for Differential and Integral Equations (Academic Press, New York, 1998)] and Abdeldaim in [On some generalizations of certain retarded nonlinear integral inequalities with iterated integrals and an application in retarded differential equation, J. Egypt. Math. Sci. Lett. 23 (2015) 470–475] and also establish some new forms.
Review of Thermal Performance and Efficiency in Evacuated Tube Solar Collector with Various Nanofluids
Authors: Kim Hyeongmin , Kim Jinhyun , Cho Honghyun
Published: April 2017

With the development of nanotechnology, building a new technology area in a variety of fields and achieving the best performance has become possible. Several studies on the performance of a solar heating system have been conducted using various nanofluids because the efficiency of heat transfer of nanofluids is high. Various previous studies, including theoretical, numerical, and experimental methods, were conducted using nanofluids for flat-plate, evacuated tube, direct solar absorption, parabolic trough, and heat pipe solar collectors. The present work provides an overview of the recent research on the performance of evacuated tube solar collectors using various nanofluids. The experimental and numerical results reported by several researchers, such as the thermal conductivity, heat capacity, and heat transfer coefficient of nanofluids, are first reported. The studies on the evacuated tube solar collectors with nanofluids were then investigated and summarized.
STATISTICAL ARBITRAGE IN THE MULTI-ASSET BLACK–SCHOLES ECONOMY
Authors: GÖNCÜ AHMET , AKYILDIRIM ERDINC
Published: April 2017

In this study, we consider the statistical arbitrage definition given in Hogan, S, R Jarrow, M Teo and M Warachka (2004). Testing market efficiency using statistical arbitrage with applications to momentum and value strategies, Journal of Financial Economics, 73, 525–565 and derive the statistical arbitrage condition in the multi-asset Black–Scholes economy building upon the single asset case studied in Göncü, A (2015). Statistical arbitrage in the Black Scholes framework. Quantitative Finance, 15(9), 1489–1499. Statistical arbitrage profits can be generated if there exists at least one asset in the economy that satisfies the statistical arbitrage condition. Therefore, adding a no-statistical arbitrage condition to no-arbitrage pricing models is not realistic if not feasible. However, with an example we show that what excludes statistical arbitrage opportunities in the Black–Scholes economy, and possibly in other complete market models, is the presence of uncertainty or stochasticity in the model parameters. Furthermore, we derive analytical formulas for the expected value and probability of loss of the statistical arbitrage portfolios and compute optimal boundaries to sell the risky assets in the portfolio by maximizing the expected return with a constraint on the probability of loss.
Referral Patterns and Diagnostic Yield of Lung Scintigraphy in the Diagnosis of Acute Pulmonary Embolism
Authors: Pelletier-Galarneau Matthieu , Zannier Erik , Zuckier Lionel S. , Le Gal Gregoire
Published: April 2017

Introduction. The purpose of this study is to assess referral patterns and the yield of ventilation-perfusion (V/Q) scintigraphy in patients referred for acute pulmonary embolism (PE). Methods. We retrospectively reviewed the charts of all patients who underwent V/Q studies between April 1, 2008, and March 31, 2010. Patients were subdivided into 4 groups based on their referral source: emergency department (ED), hospital inpatient ward, outpatient thrombosis clinic, and all other outpatient sources. Results. A total of 1008 patients underwent V/Q scintigraphy to exclude acute PE. The number of ED, inpatient, thrombosis clinic, and outpatient studies was 43 (4.3%), 288 (28.6%), 351 (34.8%), and 326 (32.3%). Proportion of patients with contrast contraindication varied significantly among the different groups. Of the 1,008 studies, 331 (32.8%) were interpreted as normal, 408 (40.5%) as low, 158 (15.7%) as intermediate, and 111 (11.0%) as high probability for PE. 68 (6.7%) patients underwent CTPA within 2 weeks following V/Q. Conclusion. The rate of nondiagnostic studies is lower than that reported in previously published data, with a relatively low rate of intermediate probability studies. Only a small fraction of patients undergoing a V/Q scan will require a CTPA.
Forecasting Performance of Lumber Futures Prices
Authors: Mehrotra Shiv N. , Carter Douglas R.
Published: April 2017

We test the forecasting power and information content of lumber futures prices traded on the Chicago Mercantile Exchange, from 1995 to 2013, at four forecast horizons. A Mincer-Zarnowitz regression finds evidence of statistically significant forecasting power at all forecast horizons. The results also support the presence of a time-varying risk premium for the shorter forecast horizons. A Granger causality test provides evidence that lumber futures prices lag spot prices in information assimilation over longer forecast horizons, while neither lagging nor leading over shorter forecast horizons.
The Tunnelling Current through Oscillating Resonance and the Sisyphus Effect
Authors: Granot Er’el
Published: April 2017

The tunnelling current through an oscillating resonance level is thoroughly investigated exactly numerically and with several approximations—analytically. It is shown that while the oscillations can increase the tunnelling current (and in several cases the increase is exponentially large), their main effect is to reduce it dramatically at certain energies. In fact, the current in the presence of the oscillations cannot increase the maximum current of the adiabatic solution. That is why, while the elevator effect does occur in this system, the Sisyphus effect is the more dominant and prominent one.
Geometry Based Approach to Obstacle Avoidance of Triomnidirectional Wheeled Mobile Robotic Platform
Authors: Gussu Tesfaye Wakessa , Lin Chyi-Yeu
Published: April 2017

Mobile robots undergo a collision-free autonomous motion by using the information obtained from a suitable combination of multiple sensors of same or different families. These sensors are often configured around the chassis of the robotic platform. However, little to no information is available as to how these sensors are configured on mobile robotic platforms and how many of these sensors to place on such platforms. Instead, an empirical approach is adopted. That is, the number of sensors of the same family or any type as well as combination of sensors for detecting obstacles is determined by experiment or information obtained from external sensors. This approach is often seen to be iterative and time consuming. In this paper, an approach for determining the minimum number of sensors and their spacing on the robotic platform is proposed so that mobile robots undergo collision-free motion. The effectiveness of the developed approach is experimentally tested by examining the obstacle avoidance capability of the triomnidirectional wheeled robotic platform based on a motion triggering signal obtained from a skirt of ultrasonic sensors only. It was observed that the newly developed approach allows this robotic platform to avoid obstacles effectively.
Clustering Classes in Packages for Program Comprehension
Authors: Sun Xiaobing , Liu Xiangyue , Li Bin , Li Bixin , Lo David , Liao Lingzhi
Published: April 2017

During software maintenance and evolution, one of the important tasks faced by developers is to understand a system quickly and accurately. With the increasing size and complexity of an evolving system, program comprehension becomes an increasingly difficult activity. Given a target system for comprehension, developers may first focus on the package comprehension. The packages in the system are of different sizes. For small-sized packages in the system, developers can easily comprehend them. However, for large-sized packages, they are difficult to understand. In this article, we focus on understanding these large-sized packages and propose a novel program comprehension approach for large-sized packages, which utilizes the Latent Dirichlet Allocation (LDA) model to cluster large-sized packages. Thus, these large-sized packages are separated as small-sized clusters, which are easier for developers to comprehend. Empirical studies on four real-world software projects demonstrate the effectiveness of our approach. The results show that the effectiveness of our approach is better than Latent Semantic Indexing- (LSI-) and Probabilistic Latent Semantic Analysis- (PLSA-) based clustering approaches. In addition, we find that the topic that labels each cluster is useful for program comprehension.
New Treatment Strategies of Depression: Based on Mechanisms Related to Neuroplasticity
Authors: Huang Yu-Jhen , Lane Hsien-Yuan , Lin Chieh-Hsin
Published: April 2017

Major depressive disorder is a severe and complex mental disorder. Impaired neurotransmission and disrupted signalling pathways may influence neuroplasticity, which is involved in the brain dysfunction in depression. Traditional neurobiological theories of depression, such as monoamine hypothesis, cannot fully explain the whole picture of depressive disorders. In this review, we discussed new treatment directions of depression, including modulation of glutamatergic system and noninvasive brain stimulation. Dysfunction of glutamatergic neurotransmission plays an important role in the pathophysiology of depression. Ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, has rapid and lasting antidepressive effects in previous studies. In addition to ketamine, other glutamatergic modulators, such as sarcosine, also show potential antidepressant effect in animal models or clinical trials. Noninvasive brain stimulation is another new treatment strategy beyond pharmacotherapy. Growing evidence has demonstrated that superficial brain stimulations, such as transcranial magnetic stimulation, transcranial direct current stimulation, cranial electrotherapy stimulation, and magnetic seizure therapy, can improve depressive symptoms. The antidepressive effect of these brain stimulations may be through modulating neuroplasticity. In conclusion, drugs that modulate neurotransmission via NMDA receptor and noninvasive brain stimulation may provide new directions of treatment for depression. Furthermore, exploring the underlying mechanisms will help in developing novel therapies for depression in the future.
Seismic Fragility Estimates of LRB Base Isolated Frames Using Performance-Based Design
Authors: Mansouri Iman , Ghodrati Amiri Gholamreza , Hu Jong Wan , Khoshkalam Mohammadreza , Soori Sanaz , Shahbazi Shahrokh
Published: April 2017

With improving technology, the idea of using energy dissipater equipment has been strengthened in order to control the structures response in dynamic loads such as wind and earthquake. In this research, we dealt with seismic performance of base isolated structures with lead-rubber bearing (LRB) using incremental dynamic analysis (IDA). For this purpose, 3- and 9-story buildings have been utilized in the SAC project undergoing 22 earthquake records which were far-fault. Plotting the fragility curve for various states of design time period and isolator damping of LRB, it is observed that, by increasing damping, the isolator has not been activated in small spectrum acceleration, which shows that the annual exceedance probability is increased in immediate occupancy (IO) performance level and decreased in life safety (LS) performance level. The results show the reduction of determined failure probability in fragility curves for two levels of performance of uninterrupted use and lateral safety. Likewise obtained results show that, with increasing design time period of isolator, the amount of failure probability is decreased rather than the isolator with smaller design time period, for both LS and IO states. And the isolator illustrates better performance.
Analysis of Dynamic Stability of Nonlinear Suspension concerning Slowly Varying Sprung Mass
Authors: Yao Jun , Zhang Jinqiu , Zhao Mingmei , Peng Hu
Published: April 2017

In this paper, the stability of vehicle concerning the slow-varying sprung mass is analyzed based on two degrees of freedom quarter-car model. A mathematical model of vehicle is established, the nonlinear vibration caused by sprung mass vibration is solved, and frequency curve is obtained. The characteristics of a stable solution and the parameters affecting the stability are analyzed. The numeric solution shows that a slow-varying sprung mass is equivalent to adding a negative damping coefficient to the suspension system, making the effective damping coefficient change from negative to positive. Such changing parameters lead to Hopf bifurcation and a shrinking limit cycle. The simulation results indicate the existence of static as well as dynamic bifurcation and the result is a change in the final stable vibration of the suspension. Even the tiny vibration of the sprung mass will lead to amplitude mutation, leading to the sprung mass instability.
Hyperparathyroidism in Pregnancy Leading to Pancreatitis and Preeclampsia with Severe Features
Authors: Dale Andrew G. , Holbrook Bradley D. , Sobel Lauren , Rappaport Valerie J.
Published: April 2017

Background. Hyperparathyroidism is underdiagnosed in pregnancy, yet early diagnosis is necessary for the potentially severe sequelae of hypercalcemia for both the woman and fetus.Case. A 31-year-old, gravida 3, para 0-0-2-0 at 32 weeks and 3 days of gestation, presented with preeclampsia with severe features concomitant with acute pancreatitis and known diabetes mellitus type 2. She was stabilized and delivered. In the postpartum period, her total calcium level remained elevated. Ionized calcium levels and parathyroid hormone levels were also elevated, and she was diagnosed with hyperparathyroidism.Conclusion. Hyperparathyroidism and hypercalcemia are risk factors for pancreatitis. Women who develop pancreatitis during pregnancy are at increased risk of developing preeclampsia. If elevated serum calcium is noted, it should be confirmed with ionized calcium level and parathyroid hormones as ionized calcium levels are unaffected by pregnancy.