bluuebunny/crossref_metadata_2025 huggingface dataset:
Medullary bone attributes in aged Lohmann LSL-lite layers fed different levels of calcium and top-dressed 25-hydroxy vitamin D3
Authors: Akbari Moghaddam Kakhki R. , Heuthorst T. , Wornath-Vanhumbeck A. , Neijat M. , Kiarie E.
Published: July 2018

Structural bone depletion over the course of lay cycle predisposes hens to skeletal problems. We investigated the effects of dietary calcium (Ca) and top-dressed 25-hydroxy vitamin D3 (25OHD3) on attributes [relative weight, ash content (AC), and ash concentration (ACN)] in whole ulna, femur, tibia, and subparts of femur and tibia (epiphysis, medullary, and cortical) in 74-wk-old Lohmann LSL-lite layers. Four levels of Ca (3.0%, 3.5%, 4.0%, and 4.5%) and three levels of 25OHD3 (0, 69, and 138 μg kg−1) were tested. All diets had basal level of 3300 IU of vitamin D3 kg−1. Eighty-four, 74-wk-old hens were placed in individual cages, and 13 spare hens were sacrificed for baseline samples. Diets (n = 7) were fed to 81 wks of age, and hens were sacrificed for bone samples. There were no (P > 0.05) diet effects on whole bone attributes. Interaction (P < 0.05) between Ca and 25OHD3 on femur subparts was such that 25OHD3 linearly increased medullary ACN and concomitantly decreased cortical ACN at all Ca levels. In tibia, 25OHD3 (P < 0.05) increased AC and ACN in medullary and reduced these parameters in cortical. The results suggested that subparts and not whole medullary bone attributes are more amenable to dietary interventions in aged hens.
Convolutional Neural Networks for Neuroimaging in Parkinson’s Disease: Is Preprocessing Needed?
Authors: Martinez-Murcia Francisco J. , Górriz Juan M. , Ramírez Javier , Ortiz Andres
Published: July 2018

Spatial and intensity normalizations are nowadays a prerequisite for neuroimaging analysis. Influenced by voxel-wise and other univariate comparisons, where these corrections are key, they are commonly applied to any type of analysis and imaging modalities. Nuclear imaging modalities such as PET-FDG or FP-CIT SPECT, a common modality used in Parkinson’s disease diagnosis, are especially dependent on intensity normalization. However, these steps are computationally expensive and furthermore, they may introduce deformations in the images, altering the information contained in them. Convolutional neural networks (CNNs), for their part, introduce position invariance to pattern recognition, and have been proven to classify objects regardless of their orientation, size, angle, etc. Therefore, a question arises: how well can CNNs account for spatial and intensity differences when analyzing nuclear brain imaging? Are spatial and intensity normalizations still needed? To answer this question, we have trained four different CNN models based on well-established architectures, using or not different spatial and intensity normalization preprocessings. The results show that a sufficiently complex model such as our three-dimensional version of the ALEXNET can effectively account for spatial differences, achieving a diagnosis accuracy of 94.1% with an area under the ROC curve of 0.984. The visualization of the differences via saliency maps shows that these models are correctly finding patterns that match those found in the literature, without the need of applying any complex spatial normalization procedure. However, the intensity normalization — and its type — is revealed as very influential in the results and accuracy of the trained model, and therefore must be well accounted.
Comment on “Efficient quantum dialogue without information leakage”
Authors: Gao Gan
Published: July 2018

In this comment, we show that the efficiency of the proposed quantum dialogue scheme in the paper [Mod. Phys. Lett. B 29 (2015) 1550018 ] cannot reach 100%, but 66.7%.
Application of a Traffic Flow Prediction Model Based on Neural Network in Intelligent Vehicle Management
Authors: Guo Yang , Lu Lu
Published: July 2018

The ultimate direction of intelligent vehicle management is to achieve artificial intelligence (AI), and data mining is an important supporting technology for AI. The adoption of new AI technology can effectively improve operational efficiency and safety, especially in terms of performance. This paper takes the researches on traffic jam as an example and proposes one algorithm for combination forecasting model based on a segmentation algorithm for traffic flow sequence and BP neural network prediction. In this paper, it also introduces the traffic flow clustering analysis and mining algorithms for congestion events at the intersections. The blocking point algorithm is improved, and experimental analysis is performed through samples. Experimental results show that the algorithm use for combination forecasting model can greatly improve the real-time performance of short-term traffic flow prediction and significantly reduce the prediction error rate. Therefore, this algorithm has practical and innovative significance in the field of intelligent vehicle management.
An Analysis of Digraphs and Period Properties of the Logistic Map on Z(pn)
Authors: Li Yongkui
Published: July 2018

This paper corrects some mistakes about three theorems, two figures and some expressions on “finite field” in a literature, and then it analyzes the digraphs and period properties of the logistic map on residue class rings [Formula: see text] and [Formula: see text]. Some theorems and conjectures are proved or given. To validate these properties, we make some numeral experiments and draw the relative figures and tables. So the theoretical analysis and numeral experiments show that there exists periods in the logistic map on [Formula: see text] and on [Formula: see text] and it can be applied in the pseudo-random generators, cryptography, spread spectrum communications and so on.
Religiosity Effects on Employees in SMEs: An Islamic Country Perspective
Authors: Ghouri Arsalan Mujahid , Khan Naveed R. , Kareem Omar B. Abdul , Shahbaz Muhammad
Published: July 2018

This study aims to investigate the adaptation of internalization factors and employees’ competitive behavior in small and medium enterprises (SMEs). The empirical findings suggest that the integration of religious orientation brings better results along with the other determinants (subjective norm, attitude, behavior control and intention) of the Theory of Planned Behavior (TPB). Further, this study indicates the significant direct relationship between religious orientation, attitude, perceived control and intention with employee behavior, except for subjective norms and intention, which shows an insignificant relationship. This empirical findings suggest that owners and managers of SMEs should place some efforts in providing support to increase religious orientation in SMEs, as this would likely to enhance all other factors. This study reports unique empirical findings to support the generalizability of the theory while also adding a new facet to the TPB by using SMEs as a social lab and data from a developing country.
Set-theoretic solutions to the Yang–Baxter equation, skew-braces, and related near-rings
Authors: Rump Wolfgang
Published: July 2018

Skew-braces have been introduced recently by Guarnieri and Vendramin. The structure group of a non-degenerate solution to the Yang–Baxter equation is a skew-brace, and every skew-brace gives a set-theoretic solution to the Yang–Baxter equation. It is proved that skew-braces arise from near-rings with a distinguished exponential map. For a fixed skew-brace, the corresponding near-rings with exponential form a category. The terminal object is a near-ring of self-maps, while the initial object is a near-ring which gives a complete invariant of the skew-brace. The radicals of split local near-rings with a central residue field [Formula: see text] are characterized as [Formula: see text]-braces with a compatible near-ring structure. Under this correspondence, [Formula: see text]-braces are radicals of local near-rings with radical square zero.
Facile Synthesis, Morphology Evolution and Tunable Luminescence of NaGdF4:Yb,Er Nanorods with Various Aspect Ratios
Authors: Gai Shasha , Jiao Jiqing , Wei Wei , Li Yao , Liu Lihua , Liu Yi , Lv Baize , Wang Yao , Belfiore Laurence A. , Tang Jianguo
Published: July 2018

The well-defined NaGdF4:Yb,Er nanorods (NRs) with various aspect ratios were synthesized using a facile hydrothermal method. The morphology and crystal phase of NRs could be controlled by reaction conditions. NaGdF4:Yb,Er NRs with various aspect ratios could be synthesized and their upconversion (UC) luminescence was tuned. It is displayed that the NRs with aspect ratios about 5 exhibited the strongest UC luminescence among samples. The growth mechanism and morphology transition of NRs had been deduced by schematic diagram. And UC mechanism had been determined by energy level diagrams. Compared with previous reports, the work provided a facial method for UCNRs with various aspect ratios at lower temperature.
Wrinkled rGO Sheets-Wrapped Carbon Fibers with High Tensile Strength and Excellent Electrochemical Stability as Anodes for Structural Li-Ion Battery
Authors: Li Huagen , Wang Shubin , Feng Mengjie , Yang Jiping , Zhang Boming
Published: July 2018

Herein, we report a hierarchical structure formed by wrinkled reduced graphene oxide (rGO) sheets-wrapped carbon fiber via a facile and efficient electrostatic self-assembly method and subsequent annealing treatment. For this material, the Weibull scale parameter is 4.77[Formula: see text]GPa. After 100 cycles, the rGO@CF retains 91% of its second charge capacity at 50[Formula: see text]mA ⋅g−1, corresponding to a capacity fading of only 0.09% per cycle. Thus, this structural anode material exhibits enhanced capacity, high initial Coulombic efficiency and high tensile strength. Meanwhile, the carbon fiber and interweaved rGO sheets together form the whole conductive networks to provide multichannel highways for charge transfer (lithium-ion diffusion and electron transport) during discharge–charge processes, promising excellent electrochemical performance of this structural anode material.
Consensus of a two-agent opinion dynamical system with processing delay
Authors: Cheng Ye , Wang Xiao , Shi Bao
Published: July 2018

A sufficient condition is obtained for a two-agent opinion dynamical system with processing delay to experience unconditional consensus. To this end, the dynamics proposed is transformed into a general class of delay differential equation and asymptotic stability of the origin is then analyzed. It is also shown that increasing delay can prolong the time needed for the system to realize consensus and even induce a Hopf bifurcation.
The semi-analytical method for inversion of a weighted vector ray transform in three dimensions
Authors: Balandin Alexander
Published: July 2018

An inversion of the weighted vector ray transform is performed jointly with the inversion of the scalar ray transform for the weighted function [Formula: see text]. Initially, the ray transform of the basis vector functions for the vector field [Formula: see text] is evaluated in an analytical form and then the inversion problem is reduced by the method of the least squares to a linear system of equations.
Fractional differential inclusions of Hilfer type under weak topologies in Banach spaces
Authors: Abbas Saïd , Benchohra Mouffak , Darwish Mohamed Abdalla
Published: July 2018

In this paper, we present some results concerning the existence of weak solutions for some functional Hilfer and Hadamard fractional differential inclusions. The Mönch’s fixed point theorem and the concept of measure of weak noncompactness are the main tools used to carry out our results.
Microscopic Understanding of Cross-Responses Between Stocks: A Two-Component Price Impact Model
Authors: Wang Shanshan , Guhr Thomas
Published: July 2018

We construct a price impact model between stocks in a correlated market. For the price change of a given stock induced by the short-term liquidity of this stock itself and of the information about other stocks, we introduce a self- and a cross-impact function of the time lag. We model the average cross-response functions for individual stocks employing the impact functions of the time lag, the impact functions of traded volumes and the trade-sign correlators. We further quantify and interpret the price impacts of time lag in terms of temporary and permanent components. To support our model, we also analyze empirical data, in particular the memory properties of the sign self- and average cross-correlators. The relation between the average cross-responses and the traded volumes which are smaller than their average is of power-law form.
Corporate Security is a Big Data Problem
Authors: Saunier Louisa , Delic Kemal A.
Published: July 2018

In modern times, we have seen a major shift toward hybrid cloud architectures, where corporations operate in a large, highly extended eco-system. Thus, the traditional enterprise security perimeter is disappearing and evolving into the concept of security intelligence where the volume, velocity/rate, and variety of data have dramatically changed. Today, to cope with the fast-changing security landscape, we need to be able to transform huge data lakes via security analytics and big data technologies into effective security intelligence presented through a security "cockpit" to achieve a better corporate security and compliance level, support sound risk management and informed decision making. We present a high-level architecture for efficient security intelligence and the concept of a security cockpit as a point of control for the corporate security and compliance state. Therefore, we could conclude nowadays corporate security can be perceived as a big-data problem.
A Chip-Level Anti-Reverse Engineering Technique
Authors: Chen Shuai , Chen Junlin , Wang Lei
Published: July 2018

Protection of intellectual property (IP) is increasingly critical for IP vendors in the semiconductor industry. However, advanced reverse engineering techniques can physically disassemble the chip and derive the IPs at a much lower cost than the value of IP design that chips carry. This invasive hardware attack—obtaining information from IC chips—always violates the IP rights of vendors. The intent of this article is to present a chip-level reverse engineering resilient design technique. In the proposed technique, transformable interconnects enable an IC chip to maintain functioning in normal use and to transform its physical structure into another pattern when exposed to invasive attacks. The newly created pattern will significantly increase the difficulty of reverse engineering. Furthermore, to improve the effectiveness of the proposed technique, a systematic design method is developed targeting integrated circuits with multiple design constraints. Simulations have been conducted to demonstrate the capability of the proposed technique, which generates extremely large complexity for reverse engineering with manageable overhead.
An Integrated Nanophotonic Parallel Adder
Authors: Ishihara Tohru , Shinya Akihiko , Inoue Koji , Nozaki Kengo , Notomi Masaya
Published: July 2018

Integrated optical circuits with nanophotonic devices have attracted significant attention due to their low power dissipation and light-speed operation. With light interference and resonance phenomena, the nanophotonic device works as a voltage-controlled optical pass-gate like a pass-transistor. This article first introduces the concept of optical pass-gate logic and then proposes a parallel adder circuit based on optical pass-gate logic. Experimental results obtained with an optoelectronic circuit simulator show the advantages of our optical parallel adder circuit over a traditional CMOS-based parallel adder circuit.
Framework for Quantifying and Managing Accuracy in Stochastic Circuit Design
Authors: Neugebauer Florian , Polian Ilia , Hayes John P.
Published: July 2018

Stochastic circuits (SCs) offer considerable area- and power-consumption benefits in various applications at the expense of computational inaccuracies. Unlike conventional logic synthesis, managing accuracy is a central problem in SC design. It is usually tackled in ad hoc fashion by multiple trial-and-error simulations that vary relevant parameters like the stochastic number length
n
. We present, for the first time, a systematic design approach to controlling the accuracy of SCs and balancing it against other design parameters. We express the (in)accuracy of a circuit processing
n
-bit stochastic numbers by the numerical deviation of the computed value from the expected result, in conjunction with a confidence level. Using the theory of Monte Carlo simulation, we derive expressions for the stochastic number length required for a desired level of accuracy or vice versa. We discuss the integration of the theory into a design framework that is applicable to both combinational and sequential SCs. We show that for combinational SCs, accuracy is independent of the circuit’s size or complexity, a surprising result. We also show how the analysis can identify subtle errors in both combinational and sequential designs. Finally, we apply the proposed methods to a case study on filtering noisy EKG signals.
FPGA Dynamic and Partial Reconfiguration
Authors: Vipin Kizheppatt , Fahmy Suhaib A.
Published: July 2018

Dynamic and partial reconfiguration are key differentiating capabilities of field programmable gate arrays (FPGAs). While they have been studied extensively in academic literature, they find limited use in deployed systems. We review FPGA reconfiguration, looking at architectures built for the purpose, and the properties of modern commercial architectures. We then investigate design flows and identify the key challenges in making reconfigurable FPGA systems easier to design. Finally, we look at applications where reconfiguration has found use, as well as proposing new areas where this capability places FPGAs in a unique position for adoption.
Framework for Rapid Performance Estimation of Embedded Soft Core Processors
Authors: Wijesundera Deshya , Prakash Alok , Srikanthan Thambipillai , Ihalage Achintha
Published: July 2018

The large number of embedded soft core processors available today make it tedious and time consuming to select the best processor for a given application. This task is even more challenging due to the numerous configuration options available for a single soft core processor while optimizing for contradicting design requirements such as performance and area. In this article, we propose a generic framework for rapid performance estimation of applications on soft core processors. The proposed technique is scalable to the large number of configuration options available in modern soft core processors by relying on rapid and accurate estimation models instead of time-consuming FPGA synthesis and execution-based techniques. Experimental results on two leading commercial soft core processors executing applications from the widely used CHStone benchmark suite show an average error of less than 6% while running in the order of minutes when compared to hours taken by synthesis-based techniques.
A Dependency Parser for Spontaneous Chinese Spoken Language
Authors: He Ruifang , Wang Yaru , Song Dawei , Zhang Peng , Jia Yuan , Li Aijun
Published: July 2018

Dependency analysis is vital for spoken language understanding in spoken dialogue systems. However, existing research has mainly focused on western spoken languages, Japanese, and so on. Little research has been done for spoken Chinese in terms of dependency parsing. Therefore, the new spoken corpus, D-ESCSC (Dependency-Expressive Speech Corpus of Standard Chinese) is built by adding new dependency relations special to spoken Chinese based on a written Chinese annotation scheme. Since spoken Chinese contains typical ill-grammatical phenomena, e.g., translocation, repetition, duplication, and omission, the new atom feature related to punctuation and three feature templates are proposed to improve a graph-based dependency parser. Experimental results on spoken Chinese corpus show that the atom feature and three templates really work and the new parser outperforms the baseline parser. To our best knowledge, it is the first work to report dependency parsing results of spoken Chinese.
Graph-Based Bilingual Word Embedding for Statistical Machine Translation
Authors: Wang Rui , Zhao Hai , Ploux Sabine , Lu Bao-Liang , Utiyama Masao , Sumita Eiichiro
Published: July 2018

Bilingual word embedding has been shown to be helpful for Statistical Machine Translation (SMT). However, most existing methods suffer from two obvious drawbacks. First, they only focus on simple contexts such as an entire document or a fixed-sized sliding window to build word embedding and ignore latent useful information from the selected context. Second, the word sense but not the word should be the minimal semantic unit; however, most existing methods still use word representation.

To overcome these drawbacks, this article presents a novel Graph-Based Bilingual Word Embedding (GBWE) method that projects bilingual word senses into a multidimensional semantic space. First, a bilingual word co-occurrence graph is constructed using the co-occurrence and pointwise mutual information between the words. Then, maximum complete subgraphs (cliques), which play the role of a minimal unit for bilingual sense representation, are dynamically extracted according to the contextual information. Consequently, correspondence analysis, principal component analyses, and neural networks are used to summarize the clique-word matrix into lower dimensions to build the embedding model.

Without contextual information, the proposed GBWE can be applied to lexical translation. In addition, given contextual information, GBWE is able to give a dynamic solution for bilingual word representations, which can be applied to phrase translation and generation. Empirical results show that GBWE can enhance the performance of lexical translation, as well as Chinese/French-to-English and Chinese-to-Japanese phrase-based SMT tasks (IWSLT, NTCIR, NIST, and WAT).
Alpha Distribution for Alpha Testing
Authors: Yuksel Cem
Published: July 2018

Alpha testing is widely used for rendering surfaces with transparency. While it works well when transparency is a binary function, semi-transparent regions cause problems, as they are classified as either fully transparent or opaque. Unfortunately, semi-transparent texture regions often appear in coarser mipmap levels, causing surfaces to disappear with distance. We introduce the alpha distribution approach for pre-processing the alpha values of a texture such that alpha testing produces expected results with semi-transparency without any modification to render-time operations. We describe two separate algorithms for alpha distribution with similar qualitative behavior. Our results show that alpha distribution can produce high-quality results with low noise. We also explain how alpha distribution can be extended for high-quality rendering with alpha-to-coverage.
Interactive Sketch-Based Normal Map Generation with Deep Neural Networks
Authors: Su Wanchao , Du Dong , Yang Xin , Zhou Shizhe , Fu Hongbo
Published: July 2018

High-quality normal maps are important intermediates for representing complex shapes. In this paper, we propose an interactive system for generating normal maps with the help of deep learning techniques. Utilizing the Generative Adversarial Network (GAN) framework, our method produces high quality normal maps with sketch inputs. In addition, we further enhance the interactivity of our system by incorporating user-specified normals at selected points. Our method generates high quality normal maps in real time. Through comprehensive experiments, we show the effectiveness and robustness of our method. A thorough user study indicates the normal maps generated by our method achieve a lower perceptual difference from the ground truth compared to the alternative methods.
PSCC
Authors: Tang Min , Liu Zhongyuan , Tong Ruofeng , Manocha Dinesh
Published: July 2018

We present a GPU-based self-collision culling method (PSCC) based on a combination of normal cone culling and spatial hashing techniques. We first describe a normal cone test front (NCTF) based parallel algorithm that maps well to GPU architectures. We use sprouting and shrinking operators to maintain compact NCTFs. Moreover, we use the NCTF nodes to efficient build an enhanced spatial hashing for triangles meshes and use that for inter-object and intra-object collisions. Compared with conventional spatial hashing, our approach provides higher culling efficiency and reduces the cost of narrow phrase culling. As compared to prior GPU-based parallel collision detection algorithm, our approach demonstrates 6-8X speedup. We also present an efficient approach for GPU-based cloth simulation based on PSCC. In practice, our GPU-based cloth simulation takes about one second per frame on complex scenes with tens or hundreds of thousands of triangles, and is about 4-6X faster than prior GPU-based simulation algorithms.
Hierarchical Visibility for Virtual Reality
Authors: Hunt Warren , Mara Michael , Nankervis Alex
Published: July 2018

We introduce a novel primary visibility algorithm based on ray casting that provides real time performance and a feature set well suited for rendering virtual reality. The flexibility provided by our approach allows for a variety of features such as lens distortion, sub-pixel rendering, very wide field of view, foveation and stochastic depth of field blur to be implemented and composed naturally while maintaining real time performance. In contrast, the current rasterization pipelines implemented in hardware require multiple passes and/or post processing to approximate these features and current highly optimized ray tracers, which primarily focus on Monte Carlo path tracing, do not achieve real time performance on current VR displays (1080x1200x2@90hz). Our approach uses a bounding volume hierarchy acceleration and a two level frustum culling/entry point search algorithm to optimize the traversal of coherent primary visibility rays. We introduce an adaptation of MSAA for raycasting that significantly lowers memory bandwidth, we leverage an AVX optimized CPU traversal to perform the majority of culling and an optimized CUDA GPU implementation for triangle intersection, multi-sample antialiasing, and shading. The implementation provides support for animation and physically-based shading and lighting. We believe this approach presents a concrete, viable alternative to rasterization that is significantly better suited to rendering for virtual and augmented reality. In order to engage the community, we have released our implementation under an open-source license.
In-Depth Buffers
Authors: Han Songfang , Chen Ge , Nehab Diego , Sander Pedro V.
Published: July 2018

We present a new approach for rendering all triangles in a model in front-to-back order without the need for sorting at runtime. The method can be used for rendering order-dependent transparency effects, or to minimize overdraw, for example. The key distinguishing component in the approach is its negligible runtime cost and therefore the ease with which it can be incorporated into rendering engines. More specifically, given a viewpoint, the runtime simply selects a presorted triangle list, which we call in-depth buffers, to be rendered at full speed. These in-depth buffers are even optimized for post-transform vertex cache efficiency. The result is unmatched in front-to-back rendering performance. The difficulty is computing the smallest set of in-depth buffers required. This reduces to a graph problem that we prove to be NP-hard. Nevertheless, we have found an optimization heuristic that produces good results, particularly when visually imperceptible fragment ordering mistakes are allowed.
HCSG
Authors: Zanni Cédric , Claux Frédéric , Lefebvre Sylvain
Published: July 2018

Constructive Solid Geometry models solids as boolean combinations of base primitives. It is one of the classical modeling approaches in Computer Graphics. With the advent of 3D printing, it has received a renewed interest: CSG affords for the robust definition of solids, and fits well with parametric modeling, affording for easy customization of existing designs.

However, the interactive display and manipulation of CSG models is challenging: Ideally, CSG has to be performed between a variety of solid representations (meshes, implicit solids, voxels) and the renderer has to provide immediate feedback during parameter exploration. The end result has to be prepared for fabrication, which involves robustly extracting cross-sections of the model.

In this work we propose a novel screen space technique for the rendering, interactive modeling and direct fabrication of parametric CSG models. It builds upon spatial hashing techniques to efficiently evaluate CSG expressions, checking whether each interval along a view ray is solid in constant time, using constant local shader memory. In addition, the scene is rendered progressively, from front to back, bounding memory usage. We describe how the hash encoding the CSG is constructed on the fly during visualization, and analyze performance on a variety of 3d models.
The Role of Viruses in the Phytobiome
Authors: Schoelz James E. , Stewart Lucy R.
Published: July 2018

Viruses are an important but sequence-diverse and often understudied component of the phytobiome. We succinctly review current information on how plant viruses directly affect plant health and physiology and consequently have the capacity to modulate plant interactions with their biotic and abiotic environments. Virus interactions with other biota in the phytobiome, including arthropods, fungi, and nematodes, may also impact plant health. For example, viruses interact with and modulate the interface between plants and insects. This has been extensively studied for insect-vectored plant viruses, some of which also infect their vectors. Other viruses have been shown to alter the impacts of plant-interacting phytopathogenic and nonpathogenic fungi and bacteria. Viruses that infect nematodes have also recently been discovered, but the impact of these and phage infecting soil bacteria on plant health remain largely unexplored.
Monitoring gastric myoelectric activity after pancreaticoduodenectomy for diet “readiness”
Authors: Dua Monica M. , Navalgund Anand , Axelrod Steve , Axelrod Lindsay , Worth Patrick J. , Norton Jeffrey A. , Poultsides George A. , Triadafilopoulos George , Visser Brendan C.
Published: July 2018

Postoperative delayed gastric emptying (DGE) is a frustrating complication of pancreaticoduodenectomy (PD). We studied whether monitoring of postoperative gastric motor activity using a novel wireless patch system can identify patients at risk for DGE. Patients ( n = 81) were prospectively studied since 2016; 75 patients total were analyzed for this study. After PD, battery-operated wireless patches (G-Tech Medical) that acquire gastrointestinal myoelectrical signals are placed on the abdomen and transmit data by Bluetooth. Patients were divided into early and late groups by diet tolerance of 7 days [enhanced recovery after surgery (ERAS) goal]. Subgroup analysis was done of patients included after ERAS initiation. The early and late groups had 50 and 25 patients, respectively, with a length of stay (LOS) of 7 and 11 days ( P < 0.05). Nasogastric insertion was required in 44% of the late group. Tolerance of food was noted by 6 versus 9 days in the early versus late group ( P < 0.05) with higher cumulative gastric myoelectrical activity. Diminished gastric myoelectrical activity accurately identified delayed tolerance to regular diet in a logistical regression analysis [area under the curve (AUC): 0.81; 95% confidence interval (CI), 0.74–0.92]. The gastric myoelectrical activity also identified a delayed LOS status with an AUC of 0.75 (95% CI, 0.67–0.88). This stomach signal continued to be predictive in 90% of the ERAS cohort, despite earlier oral intake. Measurement of gastric activity after PD can distinguish patients with shorter or longer times to diet. This noninvasive technology provides data to identify patients at risk for DGE and may guide the timing of oral intake by gastric “readiness.”

NEW & NOTEWORTHY Limited clinical indicators exist after pancreaticoduodenectomy to allow prediction of delayed gastric emptying (DGE). This study introduces a novel, noninvasive, wireless patch system capable of accurately monitoring gastric myoelectric activity after surgery. This system can differentiate patients with longer or shorter times to a regular diet as well as provide objective data to identify patients at risk for DGE. This technology has the potential to individualize feeding regimens based on gastric activity patterns to improve outcomes.
Prematurity reduces citrulline-arginine-nitric oxide production and precedes the onset of necrotizing enterocolitis in piglets
Authors: Robinson Jason L. , Smith Victoria A. , Stoll Barbara , Agarwal Umang , Premkumar Muralidhar H. , Lau Patricio , Cruz Stephanie M. , Manjarin Rodrigo , Olutoye Oluyinka , Burrin Douglas G. , Marini Juan C.
Published: July 2018

Necrotizing enterocolitis (NEC) is associated with low plasma arginine and vascular dysfunction. It is not clear whether low intestinal citrulline production, the precursor for arginine synthesis, occurs before and thus predisposes to NEC or if it results from tissue damage. This study was designed to test the hypothesis that whole body rates of citrulline, arginine, and nitric oxide synthesis are low in premature pigs and that they precede NEC. Piglets delivered by cesarean section at 103 days [preterm (PT)], 110 days [near-term (NT)], or 114 days [full-term (FT)] of gestation were given total parenteral nutrition and after 2 days orogastrically fed infant formula for 42 h to induce NEC. Citrulline and arginine fluxes were determined before and during the feeding protocol. Gross macroscopic and histological NEC scores and plasma fatty acid binding protein (iFABP) concentration were determined as indicators of NEC. Intestinal gene expression for enzymes of the arginine pathway were quantitated. A lower ( P < 0.05) survival rate was observed for PT (8/27) than for NT (9/9) and FT pigs (11/11). PT pigs had higher macroscopic gross ( P < 0.05) and histological NEC ( P < 0.05) scores and iFABP concentration ( P < 0.05) than pigs of more advanced gestational age. PT pigs had lower citrulline production and arginine fluxes ( P < 0.05) throughout and a reduced gene expression in genes of the citrulline-arginine pathway. In summary, intestinal enzyme expression and whole body citrulline and arginine fluxes were reduced in PT pigs compared with animals of more advance gestational age and preceded the development of NEC.

NEW & NOTEWORTHY Arginine supplementation prevents necrotizing enterocolitis (NEC), the most common gastrointestinal emergency of prematurity. Citrulline (precursor for arginine) production is reduced during NEC, and this is believed to be a consequence of intestinal damage. In a swine model of NEC, we show that intestinal gene expression of the enzymes for citrulline production and whole body citrulline and arginine fluxes are reduced and precede the onset of NEC in premature pigs. Reduced citrulline production during prematurity may be a predisposition to NEC.
Novel functional role of GH/IGF-I in neonatal lung myofibroblasts and in rat lung growth after intrauterine growth restriction
Authors: Nawabi Jawed , Vohlen Christina , Dinger Katharina , Thangaratnarajah Chansutha , Klaudt Christian , Lopez Garcia Eva , Hirani Dharmesh V. , Haznedar Karakaya Pinar , Macheleidt Iris , Odenthal Margarete , Nüsken Kai D. , Dötsch Jörg , Alejandre Alcazar Miguel A.
Published: July 2018

Intrauterine growth restriction (IUGR) is a risk factor for neonatal chronic lung disease (CLD) characterized by reduced alveoli and perturbed matrix remodeling. Previously, our group showed an activation of myofibroblasts and matrix remodeling in rat lungs after IUGR. Because growth hormone (GH) and insulin-like growth factor I (IGF-I) regulate development and growth, we queried 1) whether GH/IGF-I signaling is dysregulated in lungs after IUGR and 2) whether GH/IGF-I signaling is linked to neonatal lung myofibroblast function. IUGR was induced in Wistar rats by isocaloric low-protein diet during gestation. Lungs were obtained at embryonic day (E) 21, postnatal day (P) 3, P12, and P23. Murine embryonic fibroblasts (MEF) or primary neonatal myofibroblasts from rat lungs of control (pnFCo) and IUGR (pnFIUGR) were used for cell culture studies. In the intrauterine phase (E21), we found a reduction in GH receptor (GH-R), Stat5 signaling and IGF-I expression in lungs after IUGR. In the postnatal phase (P3–P23), catchup growth after IUGR was linked to increased GH mRNA, GH-R protein, activation of proliferative Stat5/Akt signaling, cyclin D1 and PCNA in rat lungs. On P23, a thickening of the alveolar septae was related to increased vimentin and matrix deposition, indicating fibrosis. In cell culture studies, nutrient deprivation blocked GH-R/IGF-IR signaling and proliferation in MEFs; this was reversed by IGF-I. Proliferation and Stat5 activation were increased in pnFIUGR. IGF-I and GH induced proliferation and migration of pnFCo; only IGF-I had these effects on pnFIUGR. Thus, we show a novel mechanism by which the GH/IGF-I axis in lung myofibroblasts could account for structural lung changes after IUGR.
Impact of endotracheal tube biofilm and respiratory secretions on airway resistance and mechanics of breathing in a neonatal lung model
Authors: Kenaley Kaitlin M. , Blackson Tom , Boylan Lori , Ciarlo Joseph , Antunes Michael , Shaffer Thomas H. , Locke Robert
Published: July 2018

Endotracheal tube (ETT) obstruction from biofilm formation is a theoretical risk for intubated preterm neonates. The objective of this study is to determine the impact of ETT biofilm on ETT resistance and minute ventilation in a neonatal respiratory model. Postextubation 2.5- and 3.0-mm ETTs from ventilated preterm infants were matched with unused control ETTs. The pressure gradient across the ETT was measured at set flow rates and converted to airway resistance. Spontaneous breathing tests (SBTs) were performed using a virtual patient model and were considered “passed” if minute ventilation of patient ETTs was greater than 60% of control ETTs. Twenty-four 2.5-mm ETTs and sixteen 3.0-mm ETTs were analyzed. In both patient and control ETTs, as flow rate increases, the pressure gradient across the ETT also increases in a linear fashion. Resistance to flow in patient ETTs was statistically different from matched control ETTs ( P < 0.001), and patient ETTs had 19.9 cmH2O·l−1·sec−1 greater resistance than control ETTs. SBTs were performed in 27 of 40 ETTs. Twenty-six ETTs “passed” an SBT. In one obstructed 3.0-mm ETT, SBT measurements were unobtainable. The clinical impact of ETT biofilm as measured by a SBT appears to be minimal for the majority of patients in our study group. In 1 out of 27 ETTs, the presence of a biofilm significantly altered resistance to airflow and resulted in a failed SBT. Gas flow rate and ETT size had a greater impact on resistance to airflow and minute ventilation than ETT biofilm in this study sample.

NEW & NOTEWORTHY This is the first study to our knowledge to characterize the impact of endotracheal tube (ETT) biofilm and respiratory secretions on resistance to airflow in a neonatal ETT using a simulation neonatal lung model. Results show that the clinical impact of ETT biofilm is minimal for the majority of patients in our study group, and ETT obstruction from biofilm is an uncommon cause of respiratory decompensation in a preterm neonate.
Neurovascular coupling during cognitive activity in adults with controlled hypertension
Authors: Lefferts Wesley K. , DeBlois Jacob P. , Barreira Tiago V. , Heffernan Kevin S.
Published: July 2018

Hypertension, even when controlled, may accelerate arterial stiffening and impair the ability of the cerebrovasculature to increase blood flow to support neural activity, i.e., neurovascular coupling (NVC). Optimal NVC depends on continuous, nonpulsatile flow, which is partially determined by extra- and intracranial vessel function. We sought to compare extra- and intracranial hemodynamics during cognitive activity (Stroop task) in 30 middle-aged, well-controlled medicated hypertensive and 30 age-, sex-, and body mass index (BMI)-matched nonhypertensive adults (56 ± 6 years, 28.2 ± 2.9 kg/m2 BMI; 32 men). Aortic and carotid (single point) pulse wave velocity (PWV) were assessed via tonometry and ultrasound, respectively. Carotid and middle cerebral artery (MCA) blood velocity pulsatility were measured via ultrasound and Doppler. Prefrontal cortex (PFC) oxygenation was measured via tissue saturation index (TSI) using near-infrared spectroscopy. Accuracy and reaction times were computed to assess cognitive performance. Stroop performance was similar between groups ( P > 0.01). Aortic and carotid PWV increased, carotid flow pulsatility decreased ( P < 0.01), and MCA flow pulsatility and PFC TSI were maintained during Stroop ( P > 0.01). Our findings indicate that middle-age adults with medically controlled hypertension and adults without hypertension demonstrate similar intra- and extracranial cerebrovascular reactivity during cognitive engagement. Despite increases in large artery stiffness, middle-aged adults with controlled hypertension and without hypertension exhibit reductions in extracranial flow pulsatility during cognitive engagement that may be part of a concerted cerebrovascular response to support downstream cerebral oxygenation and overall NVC.

NEW & NOTEWORTHY Hypertension is associated with accelerated arterial stiffening, which may alter extra- and intracranial vascular reactivity during cognitive activity and impair neurovascular coupling. Middle-aged adults with medicated hypertension exhibit similar neurovascular coupling and extra-/intracranial vascular reactivity during sustained cognitive activity. Extracranial modulation of central hemodynamics may be an important component of optimal neurovascular coupling.
Effect of intercostal muscle contraction on rib motion in humans studied by finite element analysis
Authors: Zhang Guangzhi , Chen Xian , Ohgi Junji , Jiang Fei , Sugiura Seiryo , Hisada Toshiaki
Published: July 2018

The effect of intercostal muscle contraction on generating rib motion has been investigated for a long time and is still controversial in physiology. This may be because of the complicated structure of the rib cage, making direct prediction of the relationship between intercostal muscle force and rib movement impossible. Finite element analysis is a useful tool that is good at solving complex structural mechanic problems. In this study, we individually activated the intercostal muscle groups from the dorsal to ventral portions and obtained five different rib motions classified based on rib moving directions. We found that the ribs cannot only rigidly rotate around the spinal joint but also be deformed, particularly around the relatively soft costal cartilages, where the moment of muscle force for the rigid rotation is small. Although the intercostal muscles near the costal cartilages cannot generate a large moment to rotate the ribs, the muscles may still have a potential to deform the costal cartilages and contribute to the expansion and contraction of the rib cage based on the force-length relationship. Our results also indicated that this potential is matched well with the special shape of the costal cartilages, which become progressively oblique in the caudal direction. Compared with the traditional explanation of rib motion, by additionally considering the effect from the tissue deformation, we found that the special structure of the ventral portion of the human rib cage could be of mechanical benefit to the intercostal muscles, generating inspiratory and expiratory rib motions.

NEW & NOTEWORTHY Compared with the traditional explanation of rib motion, additionally considering the effect from tissue deformation helps us understand the special structure of the ventral portion of the human rib cage, such that the costal cartilages progressively become oblique and the costochondral junction angles gradually change into nearly right angles from the upper to lower ribs, which could be of mechanical benefit to the intercostal muscles in the ventral portion, generating inspiratory and expiratory rib motions.
Steganography Algorithm Based on the Nonlocal Maximum Likelihood Noise Estimation for Mobile Applications
Authors: Carvajal-Gámez Blanca Esther , Diaz-Casco Manuel Alejandro
Published: July 2018

In recent years, thanks to the use of Internet services, daily activities used to imply movement became more accessible to any user. As a result of such interconnection, now millions of people from different countries are able to communicate among themselves through the Internet, generating a great flow of data and classified information. The information on the Internet can be stolen, intercepted, anonymized, or even destroyed, resulting in cases of infringement of intellectual property rights, and the loss or damage of data. In such a globalized and interconnected world, solid security measures have become increasingly important to ensure data privacy protection and its confidentiality during transit. Nowadays, there is a variety of security mechanisms such as the steganography, an information hiding technique, which protects intellectual property by allowing the transmission of hidden data without drawing any suspicion. In order to achieve these criteria, an adaptation of the nonlocal maximum likelihood filter is proposed; in this class of filters, in general, they are used in images that require a high level of irregular pattern detection, based on the statistical dependence of the underlying pixels of the image analysis area, when using it in the wavelet domain as edge detector and/or discontinuities in images in order to have a greater selectivity when inserting information in the image. It strengthens the detection of the areas with the highest probability of having noise presenting results which are suitable areas to insert the information and that it is imperceptible in a quantitative and qualitative manner as presented in the Results and Discussion.
Comparing the Yield of Staphylococcus aureus Recovery with Static versus Agitated Broth Incubation
Authors: Muenks Carol E. , Hogan Patrick G. , Burnham Carey-Ann D. , Fritz Stephanie A.
Published: July 2018

Given the lack of standardization of methodologies for microbial recovery from built environments, we sought to compare the yield of Staphylococcus aureus with a broth enrichment method when incubated in agitated versus static conditions. Five unique strains of S. aureus at five different concentrations were cultured to compare direct plating, agitated broth enrichment, and static broth enrichment culture methods. All samples were incubated at 35° in ambient air. The lowest concentration recovered across three replicates and five strains did not differ between culture methods (Fisher’s exact test, p=0.50); notably, recovery of S. aureus was equivalent between static and agitated broth incubation. When broth enrichment was used (both static and agitated), the burden of S. aureus growth was higher (by semiquantitative assessment of 4-quadrant streaking) compared to the direct plating culture method. Optimizing strategies for microbial recovery is essential, particularly in areas of lower biomass, given the paucity of research concerning microbial communities of built environments. The results of this study, in conjunction with other experiments investigating microbiomes of built environments, can help inform protocols for standardizing culturing methods within built environments.