bluuebunny/crossref_metadata_2025 huggingface dataset:
Fuzzy Adaptive Regularization Method for Inverse Steady-State Heat Transfer Problem
Authors: Wang Kun , Wang Guangjun
Published: January 2019

For the steady-state heat transfer process, a fuzzy adaptive regularization method (FARM) is proposed to estimate the distributed thermal boundary condition in heat transfer system. First, the relationship model between temperatures at measurement points and parameters to be estimated is established based on sensitivity matrix. The regularization term is introduced into the least-squares objective function, and then the distributed thermal boundary condition is estimated by optimizing the new objective function. A fuzzy inference mechanism is developed to ensure the adaptive ability of FARM in which the regularization parameter is updated based on the residual norm between calculated and measured temperatures at measurement points and the norm of inversion parameters. Taking the plate heat conduction system and fluid–solid conjugate heat transfer system as research objects, the effects of the parameter distribution, the number of measurement points, and measurement errors on the inversion results are discussed by numerical experiments, and comparison with the classical regularization method is also conducted. Results indicate that FARM exhibits a good adaptive ability.
Flow Behavior in Radial Vane Disk Brake Rotors at Low Rotational Speeds
Authors: Atkins Michael D. , Kienhöfer Frank W. , Kim Tongbeum
Published: January 2019

The flow behavior through the vented channel of a brake disk determines its thermal performance, viz. its resistance to brake fade, brake wear, thermal distortion, and thermal cracking. We present experimental results of the flow characteristics inside the vented channel of a radial vane brake rotor with a selected number of vanes (i.e., 18, 36, and 72) but constant porosity (ε ∼ 0.8) at low rotational speeds (i.e., 25 rpm ≤ N ≤ 400 rpm). Using bulk flow and velocity field mapping measurement techniques, we observed that increasing the number of vanes for a given rotational speed results in (i) the increase in the mass flow rate of the air pumped by the rotor, (ii) the reduction of inflow angle (β) becoming more closely aligned with the vanes, (iii) more uniformly distributed passage velocity profiles, and (iv) increased Rossby number. In addition, for a certain range of rotational speeds (i.e., 100 rpm ≤ N ≤ 400 rpm), we identified the biased development of streamwise secondary flow structures in the vented passages that only form on the inboard side of the rotor. This is due to the entry conditions where the incoming flow must transition sharply from the axial to the radial direction as air is drawn into the rotating channel. The biased secondary flow is likely to cause uneven cooling of the brake rotor, leading to thermal distortion. At lower rotational speeds (i.e., N < 100 rpm), the biased secondary flows transitions into a symmetric structure.
Kinematic Analysis of Mechanisms Based on Parametric Polynomial System: Basic Concept of a Method Using Gröbner Cover and Its Application to Planar Mechanisms
Authors: Arikawa Keisuke
Published: January 2019

Many kinematic problems in mechanisms can be represented by polynomial systems. By algebraically analyzing the polynomial systems, we can obtain the kinematic properties of the mechanisms. Among these algebraic methods, approaches based on Gröbner bases are effective. Usually, the analyses are performed for specific mechanisms; however, we often encounter phenomena for which, even within the same class of mechanisms, the kinematic properties differ significantly. In this research, we consider the cases where the parameters are included in the polynomial systems. The parameters are used to express link lengths, displacements of active joints, hand positions, and so on. By analyzing a parametric polynomial system (PPS), we intend to comprehensively analyze the kinematic properties of mechanisms represented by these parameters. In the proposed method, we first express the kinematic constraints in the form of PPS. Subsequently, by calculating the Gröbner cover of the PPS, we obtain the segmentation of the parameter space and valid Gröbner bases for each segment. Finally, we interpret the meaning of the segments and their corresponding Gröbner bases. We analyzed planar four- and five-bar linkages and five-bar truss structures using the proposed method. We confirmed that it was possible to enumerate the assembly and working modes and to identify the geometrical conditions that enable overconstrained motions.
Mechanopharmacology and Synergistic Relaxation of Airway Smooth Muscle
Authors: Wang Lu , Chitano Pasquale , Paré Peter D. , Seow Chun Y.
Published: January 2019

Asthmatic airways are stiffer than normal. We have shown that the cytoskeletal passive stiffness of airway smooth muscle (ASM) can be regulated by intracellular signaling pathways, especially those associated with Rho kinase (ROCK). We have also shown that an oscillatory strain reduces the passive stiffness of ASM and its ability to generate force. Here, we investigated the combined effect of inhibiting the ASM contraction with β2 agonist and decreasing the ASM cytoskeletal stiffness with ROCK inhibitor and/or force oscillation (FO) on the relaxation of contracted ASM. We hypothesize that the ASM relaxation can be synergistically enhanced by the combination of these interventions, because drug-induced softening of the cytoskeleton enhances the FO-induced relaxation and vice versa. Sheep tracheal strips were isotonically contracted to acetylcholine (3 × 10−5 M). At the plateau of shortening, β2 agonist salbutamol (10−7 M), ROCK inhibitor H1152 (10−7 M), and FO (square wave, 1 Hz, amplitude 6% maximal active force) were applied either alone or in combination. After adjusting for nonspecific time-dependent variation, relengthening by individual interventions with low-dose salbutamol or H1152, or small amplitude FO was not significantly different from zero. However, significant relengthening was observed in all combination treatments. The relengthening was greater than the mathematical sum of relengthening caused by individual treatments thereby demonstrating synergistic relaxation. The ASM stiffness did not change with salbutamol or H1152 treatments, but was lower with FO in combination with H1152. The results suggest that the mechanopharmacological treatment can be an effective therapy for asthma.
Control of growth orientation in as-deposited epitaxial iron-rich nickel ferrite spinel
Authors: Bratvold Jon E. , Sønsteby Henrik H. , Nilsen Ola , Fjellvåg Helmer
Published: January 2019

The authors here report epitaxial growth of the ferrimagnet NixFe3–xO4 (NFO) by atomic layer deposition at low temperatures. Films grow epitaxially at a reactor temperature of 250 °C and require no further postannealing treatment. (100)-, (110)-, and (111)-oriented thin films of NFO are attainable by using MgO (100)/LaAlO3 (100), LaAlO3 (110), and Al2O3 (001) substrates, respectively. This means that the direction of the easy axis of magnetization relative to the film surface can be selected by the choice of substrate. The authors carefully study nucleation onset and growth dynamics by varying the number of cycles used to deposit the films. This shows that the initial growth is mostly inhibited by the Fe-species, creating a small composition gradient for the first few nanometers of the film. The growth rate varies as a result of the choice of substrate, explained by the direction of the close packed layers in the film. The authors believe that the ability to deposit epitaxial ferrimagnetic films with angstrom thickness control at low temperatures will make a major impact on the possibility to grow multiferroic stacks and on low temperature monolithic device integration where a spontaneously magnetized sample is required.
Horizontal Transfer of a Retrotransposon from the Rice Planthopper to the Genome of an Insect DNA Virus
Authors: Yang Qiankun , Zhang Yan , Andika Ida Bagus , Liao Zhenfeng , Kondo Hideki , Lu Yanhua , Cheng Ye , Li Linying , He Yuqing , He Yujuan , Qi Yuhua , Sun Zongtao , Wu Yuanhua , Yan Fei , Chen Jianping , Li Junmin
Published: January 2019

This study provides an example of the horizontal transfer event from a rice planthopper genome to an IIV-6 genome. A small region of the IIV-6 genome (∼300 nt) is highly homologous to the sequences presented in high copy numbers of three rice planthopper genomes that are related to the SINEs, a class of retroposons. The expression of these planthopper SINE-like sequences was confirmed, and corresponding Piwi-interacting RNA-like small RNAs were identified and comprehensively characterized. Phylogenetic analysis suggests that the giant invertebrate iridovirus IIV-6 obtains this SINE-related sequence from
Sogatella furcifera
through a horizontal transfer event in the past. To the best of our knowledge, this is the first report of a horizontal transfer event between a planthopper and a giant DNA virus and also is the first evidence for the eukaryotic origin of genetic material in iridoviruses.
Establishment of a Novel Humanized Mouse Model To Investigate
In Vivo
Activation and Depletion of Patient-Derived HIV Latent Reservoirs
Authors: Flerin Nina C. , Bardhi Ariola , Zheng Jian Hua , Korom Maria , Folkvord Joy , Kovacs Colin , Benko Erika , Truong Ronald , Mota Talia , Connick Elizabeth , Jones R. Brad , Lynch Rebecca M. , Goldstein Harris
Published: January 2019

Sustained remission of HIV infection is prevented by a persistent reservoir of latently infected cells capable of reinitiating systemic infection and viremia. To evaluate strategies to reactivate and deplete this reservoir, we developed and characterized a new humanized mouse model consisting of highly immunodeficient mice intrasplenically injected with peripheral blood mononuclear cells from long-term ART-suppressed HIV-infected donors. Reactivation and dissemination of HIV infection was visualized in the mouse spleens in parallel with the onset of viremia. The applicability of this model for evaluating reservoir depletion treatments was demonstrated by establishing, through delayed time to viremia and phylogenetic analysis of plasma virus, that treatment of these humanized mice with a broadly neutralizing antibody, 10-1074, depleted the patient-derived population of latently infected cells. This mouse model represents a new
in vivo
approach for the preclinical evaluation of new HIV cure strategies.
Draft Genome Sequence of Sinorhizobium meliloti AK555
Authors: Muntyan Victoria S. , Baturina Olga A. , Afonin Alexey M. , Cherkasova Maria E. , Laktionov Yuri V. , Saksaganskaya Alla S. , Kabilov Marsel R. , Roumiantseva Marina L.
Published: January 2019

The inoculation of legume seeds with
Sinorhizobium
bacteria significantly improves pasture production. Here, we report the draft genome sequence of symbiotically efficient and salt-tolerant
Sinorhizobium meliloti
inoculant strain AK555, which substantially increases biomass yield of a number of
Medicago sativa
subsp.
Draft Genome Sequence of
Clostridium
sp. Strain E02, Isolated from an Estuarine Environment
Authors: Macey Michael Christopher , Curtis-Harper Elliot , Olsson-Francis Karen
Published: January 2019

Here, we report the draft genome sequence of a strain of
Clostridium
isolated from sediment collected from an estuarine environment. The strain was isolated using a minimal medium designed to select for chemoautotrophic microorganisms.
Complete Genome Sequence of a
Zucchini Yellow Mosaic Virus
Isolated from Pumpkin in Oklahoma
Authors: Khanal Vivek , Ali Akhtar
Published: January 2019

Zucchini yellow mosaic virus
(ZYMV) (genus
Potyvirus
, family
Potyviridae
) was first isolated in Europe during the 1970s and in the United States in 1981. Here, we report the complete genome sequence of ZYMV isolate BL-67, isolated from pumpkin in Oklahoma during the 2016 growing season.
Self-efficacy and risk of persistent shoulder pain: results of a Classification and Regression Tree (CART) analysis
Authors: Chester Rachel , Khondoker Mizanur , Shepstone Lee , Lewis Jeremy S , Jerosch-Herold Christina
Published: January 2019

Objectives

To (i) identify predictors of outcome for the physiotherapy management of shoulder pain and (ii) enable clinicians to subgroup people into risk groups for persistent shoulder pain and disability.

Methods

1030 people aged ≥18 years, referred to physiotherapy for the management of musculoskeletal shoulder pain were recruited. 810 provided data at 6 months for 4 outcomes: Shoulder Pain and Disability Index (SPADI) (total score, pain subscale, disability subscale) and Quick Disability of the Arm, Shoulder and Hand (QuickDASH). 34 potential prognostic factors were used in this analysis.

Results

Four classification trees (prognostic pathways or decision trees) were created, one for each outcome. The most important predictor was baseline pain and/or disability: higher or lower baseline levels were associated with higher or lower levels at follow-up for all outcomes. One additional baseline factor split participants into four subgroups. For the SPADI trees, high pain self-efficacy reduced the likelihood of continued pain and disability. Notably, participants with low baseline pain but concomitant low pain self-efficacy had similar outcomes to patients with high baseline pain and high pain self-efficacy. Cut-off points for defining high and low pain self-efficacy differed according to baseline pain and disability. In the QuickDASH tree, the association between moderate baseline pain and disability with outcome was influenced by patient expectation: participants who expected to recover because of physiotherapy did better than those who expected no benefit.

Conclusions

Patient expectation and pain self-efficacy are associated with clinical outcome. These clinical elements should be included at the first assessment and a low pain self-efficacy response considered as a target for treatment intervention.
Rumen degradability and gas production as influenced by different strains of Bacillus thuringiensis
Authors: Campos F.C. , Abdalla Filho A.L. , Corrêa P.S. , Nazato C. , Monnerat R.G. , McManus C.M. , Tsai S.M. , Abdalla A.L. , Louvandini H.
Published: January 2019

The effect of six Bacillus thuringiensis (Bt) strains on diet degradability was evaluated using an in vitro gas production technique. Spores (5.7 × 106 spores) of different Bt strains (907, 1192, 2036, 2493, 2496, and S1185) plus a control (no spores) were used as treatments with four replicates (inocula) in duplicate. Fermentation processes were evaluated and ruminal microorganisms were quantified. Compared with the control, the Bt907 strain decreased dry matter (DM) and organic matter (OM) degradability without affecting the Fibrobacter succinogenes population, whereas the other strains reduced this population without altering DM and OM degradability.
Peroxidase-like activity of palladium nanoparticles on hydrogen-bond supramolecular structures over a broader pH range and their application in glucose sensing
Authors: Zhou Nian , Zou Seyin , Zou Li , Shen Ruidi , Zhou Yamin , Ling Liansheng
Published: January 2019

To circumvent the complicated natural peroxidases, palladium nanoparticles embedded in melamine cyanurate (MCA-Pd NPs) were synthesized. MCA-Pd NPs catalyzed the oxidation of ABTS2– by H2O2, and the solution turned green, which could be quantified via a typical absorption peak at 420 nm. MCA-Pd NPs had high peroxidase-like activity in a wider pH range than that of natural peroxidases. MCA-Pd NPs were used to develop a colorimetric sensor for H2O2 over the pH range of 7.0 to 11.0, which had same linear range, and their linear regression equations had similar slopes. Moreover, MCA-Pd NPs were applied to establish the biosensor for glucose by using glucose oxidase (GOx); it had a linear range of 5.0–120 μmol/L, with a linear regression equation of A = 0.04926 + 0.00536C (C: μmol/L, R = 0.9960) and a detection limit of 0.3 μmol/L (3σ/slope). When we applied it to detect glucose level in human blood, satisfactory results were obtained.
Identifying absolute configurations of PCB atropisomers by comparison of their experimental specific rotations with their DFT calculated values
Authors: Daramola Oluwadamilola , Cullen John
Published: January 2019

Nineteen enantiomer pairs of polychlorinated biphenyls (PCBs) with three or four chloro substituents about the central carbon–carbon bond form a stable subclass of compounds whose biological effects vary with their chirality. Optical rotations for this group of PCBs were determined from density functional calculations employing extended atomic orbital gauge invariant basis sets. A comparison of these results with the experimental ones found from the literature for 10 of the pairs enabled the identification of their absolute configurations as analytes in gas chromatography studies.
Enigmatic massive sulphide mineralization in the High Arctic Large Igneous Province, Nunavut, Canada
Authors: Wilton Derek H.C. , Saumur Benoit M. , Gordon Adrian , Williamson Marie-Claude
Published: January 2019

Modern mineral exploration strategies should take into account nontraditional metallogenic models for a given geological environment. Here we document the first detailed study of a massive sulphide showing associated with the High Arctic Large Igneous Province (HALIP) and Sverdrup Basin and in fact, only the second example of mineralization described from Axel Heiberg Island, Queen Elizabeth Islands, Canadian Arctic Archipelago. The Between Lake showing (western Axel Heiberg Island) is a small massive sulphide occurrence within scree/talus below a large ridge of gabbro. It was originally described by explorationists as an orthomagmatic sulphide occurrence hosted within a dioritic dyke. New petrographic and mineralogical analyses indicate that the showing consists predominantly of pyrrhotite with lesser pyrite, trace chalcopyrite, and rare sphalerite. No Ni- or Pb-bearing sulphide minerals were detected. Geochemically, the showing contains some Co and Cu, rare Zn, and generally very low Ni contents (<9 ppm). Sulphur isotope ratios of sulphide minerals range from +3.6 to + 6.6‰, somewhat heavier than expected for magmatic-derived S but isotopically lighter than S associated with local evaporite diapirs (+5.8‰ to +12.2‰). Orthomagmatic sulphides hosted in the diorite typically exhibit even lighter isotopic ratios of –3.9‰ to –1.00‰. The data are consistent with potential mafic–siliciclastic volcanogenic massive sulphide mineralization, or the like, the first documented in the HALIP. High heat flow associated with extensive HALIP magmatism was likely the driving force for such mineralization. Mineral prospectivity in Canada’s High Arctic had been predicated upon the potential presence of magmatic Ni – Cu – platinum group element sulphide mineralization. Rather than negating this potential, our findings provide evidence for additional metallogenic potential for this region of Nunavut.
A Stochastic Queueing Model for Capacity Allocation in the Hierarchical Healthcare Delivery System
Authors: Wen Jianpei , Jiang Hanyu , Song Jie
Published: January 2019

We use the capacity allocation as a demand management tool to optimize the patient flow distribution on a hierarchical healthcare delivery system, which is a mixture of patient choice and gatekeeping. Capacity allocation for such service system can be challenging because of the inherent stochastic referral process and patients’ heterogeneous delay sensitivities. In this research, a stochastic queueing-based model is proposed to find the optimal allocation of the limited service capacity of the second level of experts. Considering the impact of the deficiency of the skill level and the amount of gatekeepers, the stochastic referral process is modeled with a tandem queue. By solving a fixed-point problem, we show that there is an unique optimal allocation and corresponding equilibrium demand. We carry out numerical studies and find that providing two alternatives for patients can be better than gatekeeper system, when the capacity of the gatekeeper is moderate compared to patients’ potential demand. Results also indicate that the optimal allocation is robust in terms of the referral rate and the mistreatment rate when two rates are less than corresponding thresholds.
The Letelier spacetime with quintessence: Solution, thermodynamics and Hawking radiation
Authors: Dias e Costa Marco M. , Toledo J. M. , Bezerra V. B.
Published: January 2019

We obtain the solution corresponding to a static and spherically symmetric black hole with a cloud of strings (Letelier spacetime) immersed in a quintessential fluid. We discuss some aspects of its thermodynamics and complete proceeding studies in the spacetime of Schwarzschild with quintessence and a solid deficit angle, which is mathematically analogous to the solution we obtained. We also present a discussion about Hawking radiation of particles, in the background under consideration and compare with related studies in the literature.
Sheaf lines of Yang–Mills instanton sheaves
Authors: Lai Sheng-Hong , Lee Jen-Chi , Tsai I-Hsun
Published: January 2019

We calculate a sheaf line in [Formula: see text] which is the real line supporting sheaf points on [Formula: see text] of [Formula: see text] Yang–Mills (YM) instanton (or [Formula: see text] complex YM instanton) sheaves for some given ADHM data we obtained previously. We found that this sheaf line is indeed a special jumping line over [Formula: see text] spacetime. In addition, we calculate the singularity structure of the connection [Formula: see text] and the field strength [Formula: see text] at the corresponding singular point on [Formula: see text] of this sheaf line. We found that the order of singularity at the singular point on [Formula: see text] associated with the sheaf line in [Formula: see text] is higher than those of other singular points associated with normal jumping lines. We conjecture that this is a general feature for sheaf lines among jumping lines.
Theoretical assessment of the impact of environmental contamination on the dynamical transmission of polio
Authors: Balde C. , Lam M. , Bah A. , Bowong S. , Tewa J. J.
Published: January 2019

A mathematical model for the dynamical transmission of polio is considered, with the aim of investigating the impact of environment contamination. The model captures two infection pathways through both direct human-to-human transmission and indirect human-to-environment-to-human transmission by incorporating the environment as a transition and/or reservoir of viruses. We derive the basic reproduction number [Formula: see text]. We show that the disease free equilibrium is globally asymptotically stable (GAS) if [Formula: see text], while if [Formula: see text], there exists a unique endemic equilibrium which is locally asymptotically stable (LAS). Similar results hold for environmental contamination free sub-model (without the incorporation of the indirect transmission). At the endemic level, we show that the number of infected individuals for the model with the environmental-related contagion is greater than the corresponding number for the environmental contamination free sub-model. In conjunction with the inequality [Formula: see text], where [Formula: see text] is the basic reproduction number for the environmental contamination free sub-model, our finding suggests that the contaminated environment plays a detrimental role on the transmission dynamics of polio disease by increasing the endemic level and the severity of the outbreak. Therefore, it is natural to implement control strategies to reduce the severity of the disease by providing adequate hygienic living conditions, educate populations at risk to follow rigorously those basic hygienic rules in order to avoid adequate contacts with suspected contaminated objects. Further, we perform numerical simulations to support the theory.
New results for a Lasota–Wazewska model
Authors: Chérif Farouk , Miraoui Mohsen
Published: January 2019

In nature there is no phenomenon that is purely periodic, and this gives the idea to consider the measure pseudo almost periodic oscillation. In this paper, by employing a suitable fixed point theorem, the properties of the measure pseudo almost periodic functions and differential inequality, we investigate the existence and uniqueness of the measure pseudo almost periodic solutions for some models of Lasota–Wazewska equation with measure pseudo almost periodic coefficients and mixed delays. We suppose that the linear part has almost periodic and the nonlinear part is assumed to be measure pseudo almost periodic. Moreover, the global attractivity and the exponential stability of the measure pseudo almost periodic solutions are also considered for the system. As application, an illustrative numerical example is given to demonstrate the effectiveness of the obtained results.
Privacy-Preserving Truth Discovery in Crowd Sensing Systems
Authors: Miao Chenglin , Jiang Wenjun , Su Lu , Li Yaliang , Guo Suxin , Qin Zhan , Xiao Houping , Gao Jing , Ren Kui
Published: January 2019

The recent proliferation of human-carried mobile devices has given rise to the crowd sensing systems. However, the sensory data provided by individual participants are usually not reliable. To better utilize such sensory data, the topic of truth discovery, whose goal is to estimate user quality and infer reliable aggregated results through quality-aware data aggregation, has drawn significant attention. Though able to improve aggregation accuracy, existing truth discovery approaches fail to address the privacy concerns of individual users. In this article, we propose a novel privacy-preserving truth discovery (PPTD) framework, which can protect not only users’ sensory data but also their reliability scores derived by the truth discovery approaches. The key idea of the proposed framework is to perform weighted aggregation on users’ encrypted data using a homomorphic cryptosystem, which can guarantee both high accuracy and strong privacy protection. In order to deal with large-scale data, we also propose to parallelize PPTD with MapReduce framework. Additionally, we design an incremental PPTD scheme for the scenarios where the sensory data are collected in a streaming manner. Extensive experiments based on two real-world crowd sensing systems demonstrate that the proposed framework can generate accurate aggregated results while protecting users’ private information.
Efficient Fine-grained Processor-logic Interactions on the Cache-coherent Zynq Platform
Authors: Kroh Alexander , Diessel Oliver
Published: January 2019

The introduction of cache-coherent processor-logic interconnects in CPU-FPGA platforms promises low-latency communication between CPU and FPGA fabrics. This reduced latency improves the performance of heterogeneous systems implemented on such devices and gives rise to new software architectures that can better use the available hardware.

Via an extended study accelerating the software task scheduler of a microkernel operating system, this article reports on the potential for accelerating applications that exhibit fine-grained interactions. In doing so, we evaluate the performance of direct and cache-coherent communication methods for applications that involve frequent, low-bandwidth transactions between CPU and programmable logic.

In the specific case we studied, we found that replacing a highly optimised software implementation of the task scheduler with an FPGA-based scheduler reduces the cost of communication between two software threads by 5.5%. We also found that, while hardware acceleration reduces cache footprint, we still observe execution time variability because of other non-deterministic features of the CPU.
Momentum
Authors: Balsamo Domenico , Fletcher Benjamin J. , Weddell Alex S. , Karatziolas Giorgos , Al-Hashimi Bashir M. , Merrett Geoff V.
Published: January 2019

Recent research has looked to supplement or even replace the batteries in embedded computing systems with energy harvesting, where energy is derived from the device’s environment. However, such supplies are generally unpredictable and highly variable, and hence systems typically incorporate large external energy buffers (e.g., supercapacitors) to sustain computation; however, these pose environmental issues and increase system size and cost. This article proposes
Momentum
, a general power-neutral methodology, with intrinsic system-wide maximum power point tracking, that can be applied to a wide range of different computing systems, where the system dynamically scales its performance (and hence power consumption) to optimize computational progress depending on the power availability.
Momentum
enables the system to operate around an efficient operating voltage, maximizing forward application execution, without adding any external tracking or control units. This methodology combines at runtime (1) a hierarchical control strategy that utilizes available power management controls (such as dynamic voltage and frequency scaling, and core hot-plugging) to achieve efficient power-neutral operation; (2) a software-based maximum power point tracking scheme (unlike existing approaches, this does not require any additional hardware), which adapts the system power consumption so that it can work at the optimal operating voltage, considering the efficiency of the entire system rather than just the energy harvester; and (3) experimental validation on two different scales of computing system: a low power microcontroller (operating from the already-present 4.7μF decoupling capacitance) and a multi-processor system-on-chip (operating from 15.4mF added capacitance). Experimental results from both a controlled supply and energy harvesting source show that
Momentum
operates correctly on both platforms and exhibits improvements in forward application execution of up to 11% when compared to existing power-neutral approaches and 46% compared to existing static approaches.
Self-learnable Cluster-based Prefetching Method for DRAM-Flash Hybrid Main Memory Architecture
Authors: Yoon Su-Kyung , Youn Young-Sun , Burgstaller Bernd , Kim Shin-Dug
Published: January 2019

This article presents a novel prefetching mechanism for memory-intensive workloads used in large-scale data centers. We design a negative-AND-flash/dynamic random-access memory (DRAM) hybrid memory architecture as a cost-effective memory architecture to resolve the scalability and power consumption problems of a DRAM-based model. A smart prefetching mechanism based on a cluster-management scheme to cope with dynamically varying and complex access patterns of any given application is designed for maximizing the performance of the DRAM. In this article, we propose a new concept for page management, called a cluster, which prefetches data in our hybrid memory architecture. The cluster management is based on a self-learning scheme on dynamically changeable access patterns by considering any correlation between missed pages. Experimental results show that the overall performance is significantly improved in relation to hit rate, execution time, and energy consumption. Namely, our proposed model can enhance the hit rate by 15% and reduce the execution time by 1.75 times. In addition, we can save energy consumption by around 48% by cutting the number of flushed pages to about an eighth of that in a conventional system.
Differentiating Regularization Weights -- A Simple Mechanism to Alleviate Cold Start in Recommender Systems
Authors: Chen Hung-Hsuan , Chen Pu
Published: January 2019

Matrix factorization (MF) and its extended methodologies have been studied extensively in the community of recommender systems in the last decade. Essentially, MF attempts to search for low-ranked matrices that can (1) best approximate the known rating scores, and (2) maintain low Frobenius norm for the low-ranked matrices to prevent overfitting. Since the two objectives conflict with each other, the common practice is to assign the relative importance weights as the hyper-parameters to these objectives. The two low-ranked matrices returned by MF are often interpreted as the latent factors of a user and the latent factors of an item that would affect the rating of the user on the item. As a result, it is typical that, in the loss function, we assign a regularization weight λ

p

on the norms of the latent factors for all users, and another regularization weight λ

q

on the norms of the latent factors for all the items. We argue that such a methodology probably over-simplifies the scenario. Alternatively, we probably should assign lower constraints to the latent factors associated with the items or users that reveal more information, and set higher constraints to the others. In this article, we systematically study this topic. We found that such a simple technique can improve the prediction results of the MF-based approaches based on several public datasets. Specifically, we applied the proposed methodology on three baseline models -- SVD, SVD++, and the NMF models. We found that this technique improves the prediction accuracy for all these baseline models. Perhaps more importantly, this technique better predicts the ratings on the long-tail items, i.e., the items that were rated/viewed/purchased by few users. This suggests that this approach may partially remedy the cold-start issue. The proposed method is very general and can be easily applied on various recommendation models, such as Factorization Machines, Field-aware Factorization Machines, Factorizing Personalized Markov Chains, Prod2Vec, Behavior2Vec, and so on. We release the code for reproducibility. We implemented a Python package that integrates the proposed regularization technique with the SVD, SVD++, and the NMF model. The package can be accessed at https://github.com/ncu-dart/rdf.
RESTful API Automated Test Case Generation with EvoMaster
Authors: Arcuri Andrea
Published: January 2019

RESTful APIs are widespread in industry, especially in enterprise applications developed with a microservice architecture. A RESTful web service will provide data via an API over the network using HTTP, possibly interacting with databases and other web services. Testing a RESTful API poses challenges, because inputs/outputs are sequences of HTTP requests/responses to a remote server. Many approaches in the literature do black-box testing, because often the tested API is a remote service whose code is not available. In this article, we consider testing from the point of view of the developers, who have full access to the code that they are writing. Therefore, we propose a fully automated white-box testing approach, where test cases are automatically generated using an evolutionary algorithm. Tests are rewarded based on code coverage and fault-finding metrics. However, REST is not a protocol but rather a set of guidelines on how to design resources accessed over HTTP endpoints. For example, there are guidelines on how related resources should be structured with hierarchical URIs and how the different HTTP verbs should be used to represent well-defined actions on those resources. Test-case generation for RESTful APIs that only rely on white-box information of the source code might not be able to identify how to create prerequisite resources needed before being able to test some of the REST endpoints. Smart sampling techniques that exploit the knowledge of best practices in RESTful API design are needed to generate tests with predefined structures to speed up the search. We implemented our technique in a tool called E
vo
M
aster
, which is open source. Experiments on five open-source, yet non-trivial, RESTful services show that our novel technique automatically found 80 real bugs in those applications. However, obtained code coverage is lower than the one achieved by the manually written test suites already existing in those services. Research directions on how to further improve such an approach are therefore discussed, such as the handling of SQL databases.
GroupSense
Authors: Abkenar Amin B. , Loke Seng W. , Zaslavsky Arkady , Rahayu Wenny
Published: January 2019

Human activity recognition using embedded mobile and embedded sensors is becoming increasingly important. Scaling up from individuals to groups, that is, Group Activity Recognition (GAR), has attracted significant attention recently. This article proposes a model and modeling language for GAR called
GroupSense-L
and a novel distributed middleware called
GroupSense
for mobile GAR. We implemented and tested GroupSense using smartphone sensors, smartwatch sensors, and embedded sensors in things, where we have a protocol for these different devices to exchange information required for GAR. A range of continuous group activities (from simple to fairly complex) illustrates our approach and demonstrates the feasibility of our model and richness of the proposed specialization. We then conclude with lessons learned for GAR and future work.
Metals and Mechanisms of Carcinogenesis
Authors: Chen Qiao Yi , DesMarais Thomas , Costa Max
Published: January 2019

Metal exposure is pervasive and not limited to sporadic poisoning events or toxic waste sites. Hundreds of millions of people around the globe are affected by chronic metal exposure, which is associated with serious health concerns, including cancer, as demonstrated in a variety of studies at the molecular, systemic, and epidemiologic levels. Metal-induced toxicity and carcinogenicity are sophisticated and complex in nature. This review provides a broad context and holistic view of currently available studies on the mechanisms of metal-induced carcinogenesis. Specifically, we focus on the five most prevalent carcinogenic metals, arsenic, nickel, cadmium, chromium, and beryllium, and their potential to drive carcinogenesis in humans. A comprehensive understanding of the mechanisms behind the development of metal-induced cancer can provide valuable insights for therapeutic intervention involving molecular targets in metal-induced carcinogenesis.
Pharmacologic Targeting of Hypoxia-Inducible Factors
Authors: Semenza Gregg L.
Published: January 2019

Hypoxia-inducible factors (HIFs) control transcriptional responses to reduced O2availability. HIFs are heterodimeric proteins composed of an O2-regulated HIF-α subunit and a constitutively expressed HIF-1β subunit. HIF-α subunits are subject to prolyl hydroxylation, which targets the proteins for degradation under normoxic conditions. Small molecule prolyl hydroxylase inhibitors, which stabilize the HIF-α subunits and increase HIF-dependent expression of erythropoietin, are in phase III clinical trials for the treatment of anemia in patients with chronic kidney disease. HIFs contribute to the pathogenesis of many cancers, particularly the clear cell type of renal cell carcinoma in which loss of function of the von Hippel-Lindau tumor suppressor blocks HIF-2α degradation. A small molecule inhibitor that binds to HIF-2α and blocks dimerization with HIF-1β is in clinical trials for the treatment of renal cell carcinoma. Targeting HIFs for stabilization or inhibition may improve outcomes in diseases that are common causes of mortality in the US population.
Cold acclimation enhances UCP1 content, lipolysis, and triacylglycerol resynthesis, but not mitochondrial uncoupling and fat oxidation, in rat white adipocytes
Authors: Sepa-Kishi Diane M. , Jani Shailee , Da Eira Daniel , Ceddia Rolando B.
Published: January 2019

The objective of this study was to investigate whether cold-induced browning of the subcutaneous (Sc) inguinal (Ing) white adipose tissue (WAT) increases the capacity of this tissue to oxidize fatty acids through uncoupling protein 1 (UCP1)-mediated thermogenesis. To accomplish that, rats were acclimated to cold (4°C for 7 days). Subsequently, interscapular and aortic brown adipose tissues (iBAT and aBAT, respectively), epididymal (Epid), and Sc Ing WAT were used for adipocyte isolation. In BAT adipocytes, cold acclimation increased UCP1 content and palmitate oxidation either in the absence or presence of oligomycin, whereas in Sc Ing adipocytes glucose and palmitate oxidation were not affected, although multilocular adipocytes were formed and UCP1 content increased upon cold acclimation in the WAT. Furthermore, isoproterenol-stimulated cold Sc Ing adipocytes exhibited significantly lower rates of palmitate oxidation than control cells when exposed to oligomycin. These findings provide evidence that, despite increasing UCP1 levels, cold acclimation essentially reduced mitochondrial uncoupling-mediated fat oxidation in Sc Ing adipocytes. Conversely, glycerol kinase and phosphoenolpyruvate carboxykinase levels, isoproterenol-induced lipolysis, as well as glycerol and palmitate incorporation into lipids significantly increased in these cells. Therefore, instead of UCP1-mediated mitochondrial uncoupling, cold acclimation increased the capacity of Sc Ing adipocytes to export fatty acids and enhanced key components of the triacylglycerol resynthesis pathway in the Sc Ing WAT.
Dopamine promotes colonic mucus secretion through dopamine D5 receptor in rats
Authors: Li Yun , Zhang Yue , Zhang Xiao-Li , Feng Xiao-Yan , Liu Chen-Zhe , Zhang Xiu-Neng , Quan Zhu-Sheng , Yan Jing-Ting , Zhu Jin-Xia
Published: January 2019

Dopamine regulates gastrointestinal mucosal barrier. Mucus plays important roles in the protection of intestinal mucosa. Here, the regulatory effect of dopamine on rat colonic mucus secretion was investigated. RT-PCR, immunofluorescence, Periodic Acid-Schiff reagent assay, Alcian blue-Periodic Acid-Schiff staining, and enzyme-linked immunosorbent assay were used to observe the expression of dopamine receptor and the direct effect of dopamine on the colonic mucus. Mice injected intraperitoneally with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) destroying enteric dopamine (DA) neurons, rats microinjected with 6-hydroxydopamine (6-OHDA) into the bilateral substantia nigra damaging central dopaminergic neurons, and dopamine D5 receptor-downregulated transgenic mice were used to detect the effect of endogenous enteric dopamine or dopamine receptors on distal colonic mucus. Our results indicated that D5 immunoreactivity was widely distributed on the colonic goblet cells. Dopamine dose-dependently increased rat distal colonic mucus secretion in vitro. D1-like receptor antagonist SCH23390 inhibited dopamine (1 μΜ)-induced distal colonic mucus secretion. D1-like receptor agonist SKF38393 promoted mucin 2 (MUC2) secretion and increased the intracellular cAMP level of colonic mucosa. D5 receptor-downregulated transgenic mice showed a decreased colonic MUC2 content. MPTP-treated mice exhibited lower colonic dopamine content and decreased colonic mucus content. 6-OHDA rats had an increase in the dopamine content in colonic mucosa but decreases in the protein levels of D1 and D5 receptors and MUC2 content in the colonic mucosa. These findings reveal that dopamine is able to promote distal colonic mucus secretion through the D5 receptor, which provides important evidence to better understand the possible role of dopamine in the colonic mucosal barrier.
Altered skeletal muscle microtubule-mitochondrial VDAC2 binding is related to bioenergetic impairments after paclitaxel but not vinblastine chemotherapies
Authors: Ramos Sofhia V. , Hughes Meghan C. , Perry Christopher G. R.
Published: January 2019

Microtubule-targeting chemotherapies are linked to impaired cellular metabolism, which may contribute to skeletal muscle dysfunction. However, the mechanisms by which metabolic homeostasis is perturbed remains unknown. Tubulin, the fundamental unit of microtubules, has been implicated in the regulation of mitochondrial-cytosolic ADP/ATP exchange through its interaction with the outer membrane voltage-dependent anion channel (VDAC). Based on this model, we predicted that disrupting microtubule architecture with the stabilizer paclitaxel and destabilizer vinblastine would impair skeletal muscle mitochondrial bioenergetics. Here, we provide in vitro evidence of a direct interaction between both α-tubulin and βII-tubulin with VDAC2 in untreated single extensor digitorum longus (EDL) fibers. Paclitaxel increased both α- and βII-tubulin-VDAC2 interactions, whereas vinblastine had no effect. Utilizing a permeabilized muscle fiber bundle preparation that retains the cytoskeleton, paclitaxel treatment impaired the ability of ADP to attenuate H2O2 emission, resulting in greater H2O2 emission kinetics. Despite no effect on tubulin-VDAC2 binding, vinblastine still altered mitochondrial bioenergetics through a surprising increase in ADP-stimulated respiration while also impairing ADP suppression of H2O2 and increasing mitochondrial susceptibility to calcium-induced formation of the proapoptotic permeability transition pore. Collectively, these results demonstrate that altering microtubule architecture with chemotherapeutics disrupts mitochondrial bioenergetics in EDL skeletal muscle. Specifically, microtubule stabilization increases H2O2 emission by impairing ADP sensitivity in association with greater tubulin-VDAC binding. In contrast, decreasing microtubule abundance triggers a broad impairment of ADP’s governance of respiration and H2O2 emission as well as calcium retention capacity, albeit through an unknown mechanism.
T1R2+T1R3-independent chemosensory inputs contributing to behavioral discrimination of sugars in mice
Authors: Schier Lindsey A. , Inui-Yamamoto Chizuko , Blonde Ginger D. , Spector Alan C.
Published: January 2019

Simple sugars are thought to elicit a unitary sensation, principally via the “sweet” taste receptor type 1 taste receptor (T1R)2+T1R3, yet we previously found that rats with experience consuming two metabolically distinct sugars, glucose and fructose, subsequently licked more for glucose than fructose, even when postingestive influences were abated. The results pointed to the existence of an orosensory receptor that binds one sugar but not the other and whose signal is channeled into neural circuits that motivate ingestion. Here we sought to determine the chemosensory nature of this signal. First, we assessed whether T1R2 and/or T1R3 are necessary to acquire this behavioral discrimination, replicating our rat study in T1R2+T1R3 double-knockout (KO) mice and their wild-type counterparts as well as in two common mouse strains that vary in their sensitivity to sweeteners [C57BL/6 (B6) and 129X1/SvJ (129)]. These studies showed that extensive exposure to multiple concentrations of glucose and fructose in daily one-bottle 30-min sessions enhanced lick responses for glucose over fructose in brief-access tests. This was true even for KO mice that lacked the canonical “sweet” taste receptor. Surgical disconnection of olfactory inputs to the forebrain (bulbotomy) in B6 mice severely disrupted the ability to express this experience-dependent sugar discrimination. Importantly, these bulbotomized B6 mice exhibited severely blunted responsiveness to both sugars relative to water in brief-access lick tests, despite the fact that they have intact T1R2+T1R3 receptors. The results highlight the importance of other sources of chemosensory and postingestive inputs in shaping and maintaining “hardwired” responses to sugar.