bluuebunny/crossref_metadata_2025 huggingface dataset:
A note on some Bianchi type II spacetimes and their conformal vector fields in f(R) theory of gravity
Authors: Hussain Fiaz , Shabbir Ghulam , Jamal S. , Ramzan Muhammad
Published: September 2019

The aim of this paper is to find proper conformal vector fields of some Bianchi type II spacetimes in the f[Formula: see text](R[Formula: see text]) theory of gravity using direct integration technique. In this study, seven cases have been discussed. Studying each case in detail, it is shown that the spacetimes under consideration do not admit proper conformal vector fields. Conformal vector fields are either homothetic vector fields or Killing vector fields.
Bc excitations at LHC experiments
Authors: Berezhnoy A. V. , Belov I. N. , Likhoded A. K. , Luhinsky A. V.
Published: September 2019

The 2S [Formula: see text] states observed by ATLAS, CMS and LHCb Collaborations are discussed. The observation perspectives of [Formula: see text], 2P wave, 3P wave and D wave states of [Formula: see text] at LHC experiments are estimated.
CA-Based Detection of Coherence Exploiting Hardware Trojans
Authors: Hazra Suvadip , Dalui Mamata
Published: September 2019

Nowadays, Hardware Trojan threats have become inevitable due to the growing complexities of Integrated Circuits (ICs) as well as the current trend of Intellectual Property (IP)-based hardware designs. An adversary can insert a Hardware Trojan during any of its life cycle phases — the design, fabrication or even at manufacturing phase. Once a Trojan is inserted into a system, it can cause an unwanted modification to system functionality which may degrade system performance or sometimes Trojans are implanted with the target to leak secret information. Once Trojans are implanted, they are hard to detect and impossible to remove from the system as they are already fabricated into the chip. In this paper, we propose three stealthy Trojan models which affect the coherence mechanism of Chip Multiprocessors’ (CMPs) cache system by arbitrarily modifying the cache block state which in turn may leave the cache line states as incoherent. We have evaluated the payload of such modeled Trojans and proposed a cellular automaton (CA)-based solution for detection of such Trojans.
Cascaded Dense-UNet for Image Super-Resolution
Authors: Zang Huaijuan , Zhu Leilei , Ding Zhenglong , Li Xinke , Zhan Shu
Published: September 2019

Recently, deep convolutional neural networks (CNNs) have achieved great success in single image super-resolution (SISR). Especially, dense skip connections and residual learning structures promote better performance. While most existing deep CNN-based networks exploit the interpolation of upsampled original images, or do transposed convolution in the reconstruction stage, which do not fully employ the hierarchical features of the networks for final reconstruction. In this paper, we present a novel cascaded Dense-UNet (CDU) structure to take full advantage of all hierarchical features for SISR. In each Dense-UNet block (DUB), many short, dense skip pathways can facilitate the flow of information and integrate the different receptive fields. A series of DUBs are concatenated to acquire high-resolution features and capture complementary contextual information. Upsampling operators are in DUBs. Furthermore, residual learning is introduced to our network, which can fuse shallow features from low resolution (LR) image and deep features from cascaded DUBs to further boost super-resolution (SR) reconstruction results. The proposed method is evaluated quantitatively and qualitatively on four benchmark datasets, our network achieves comparable performance to state-of-the-art super-resolution approaches and obtains pleasant visualization results.
Design and Analysis of Power Efficient TG Based Dual Edge Triggered Flip-Flops with Stacking Technique
Authors: Sabu Neethu Anna , Batri K.
Published: September 2019

One of the paramount issues in the field of VLSI design is the rapid increase in power consumption. Therefore, it is necessary to develop power-efficient circuits. Here, three new simple architectures are presented for a Dynamic Double Edge Triggered Flip-flop named as Transistor Count Reduction Flip-flop, S-TCRFF (Series Stacking in TCRFF) and FST in TCRFF (Forced Stacking of Transistor in TCRFF). The first one features a dynamic design comprising of transmission gate in which total transistor count has greatly reduced without affecting the logic, thereby attaining better power and speed performance. For the reduction of static power, two types of stacking called series and forced transistor stacking are applied. The circuits are simulated using Cadence Virtuoso in 45[Formula: see text]nm CMOS technology with a power supply of 1[Formula: see text]V at 500[Formula: see text]MHz when input switching activity is 25%. The simulated results indicated that the new designs (TCRFF, S-TCRFF and FST in TCRFF) excelled in different circuit performance indices like Power-Delay-Product (PDP), Energy-Delay-Product (EDP), average and leakage power with less layout area compared with the performance of nine recently proposed FF designs. The improvement in PDPdq value was up to 89.2% (TCRFF), 89.9% (S-TCRFF) and 90.3% (FST in TCRFF) with conventional transmission gate FF (TGFF).
Application of the Computer Capacity to the Analysis of Processors Evolution
Authors: Ryabko Boris , Rakitskiy Anton
Published: September 2019

The concept of the so-called computer capacity was proposed in 2012 and applied for analysis of processors of different kinds. Here, we analyze the evolution of processors using the computer capacity as the main tool of analysis. It is shown that during the transition “from old to new” the manufacturers change the parameters that affect the computer capacity. It allows us to predict the values of parameters of following processors. Intel processors are used as the main example due to their high popularity and the accessibility of detailed description of all the technical characteristics.
A Temperature-Stable Low-Power Wide-Range CMOS Voltage Controlled Oscillator Design for Biomedical Applications
Authors: Sakka Zied , Gargouri Nadia , Samet Mounir
Published: September 2019

This paper presents a low power temperature compensated CMOS ring oscillator for biomedical applications across a wide temperature range. The proposed circuit deploys an IPTAT (inversely proportional to absolute temperature) bias current by generating an adaptive control voltage in each stage of the oscillator to compensate the overall oscillator’s temperature coefficient (TC). Simulations using TSMC 0.18[Formula: see text][Formula: see text]m CMOS technology show that this configuration can achieve a frequency variation less than 0.25%, leading to an average frequency drift of 20.83[Formula: see text]ppm/∘C.

Monte Carlo simulations have also been performed and demonstrate a 3[Formula: see text] deviation of about 2.15%. The power dissipated by the proposed circuit is only 8.48[Formula: see text]mW at 25∘C.
Analytical validation of the Young–Dupré law for epitaxially-strained thin films
Authors: Davoli Elisa , Piovano Paolo
Published: September 2019

We present here an analysis of the regularity of minimizers of a variational model for epitaxially strained thin-films. The regularity of energetically-optimal film profiles is studied by extending previous methods and by developing new ideas based on transmission problems. The achieved regularity results relate to both the Stranski-Krastanow and the Volmer-Weber modes, the possibility of different elastic properties between the film and the substrate, and the presence of the surface tensions of all three involved interfaces: film/gas, substrate/gas, and film/substrate. Finally, geometrical conditions are provided for the optimal wetting angle, i.e. the angle formed at the contact point of films with the substrate. In particular, the Young–Dupré law is shown to hold, yielding what appears to be the first analytical validation of such law for a thin-film model in the context of Continuum Mechanics.
Emergent behaviors of the swarmalator model for position-phase aggregation
Authors: Ha Seung-Yeal , Jung Jinwook , Kim Jeongho , Park Jinyeong , Zhang Xiongtao
Published: September 2019

We study emergent dynamics of the swarmalator model [K. P. O’Keeffe, H. Hong and S. H. Strogatz, Oscillators that sync and swarm, Nature Commun. 8 (2017) 1504] describing the dynamic interplay of aggregation and synchronization dynamics for interacting many-particle systems. For the particle aggregation, we employ the nonlinear aggregation system with singular attractive–repulsive couplings depending on the phase differences, while we use the Kuramoto-type model with the singular coupling strength depending on the spatial distances for the dynamics of phases. We show how collective behaviors emerge from the dynamic interplay between position aggregation and phase synchronization. We introduce some sufficient framework leading to the positive minimal relative distances between particles and its uniform upper bound. We also show the convergence of position under some sufficient conditions.
Dynamical behavior of the universe: An entropic force scenario
Authors: Abchouyeh Maryam Aghaei , Mirza Behrouz , Sadeghi Fatemeh
Published: September 2019

Entropic force originates in the assumption that there is a horizon for the universe. This horizon gives rise to additional terms in the equations of motion. Using dynamical system calculations, our results show that in the presence of dark energy for certain conditions, the last attractor of this theory will be dark energy epoch, but in the absence of dark energy, entropic force energy portion will have the lead role in the late time universe and is responsible for accelerated expansion of that. Interestingly, assuming both entropic force terms and dark energy to have their share of energy density of the universe, we have found that, in certain conditions entropic force dominated epoch is a stable fixed point while the dark energy epoch is a saddle point.
Dark energy from nondegenerate Higgs-vacuum
Authors: Usman Muhammad , Qadir Asghar
Published: September 2019

Scalar fields are favorite among the possible candidates for the dark energy. Most frequently discussed are those with degenerate minima at [Formula: see text]. In this paper, a slightly modified two-Higgs doublet model is taken to contain the Higgs field(s) as the dark energy candidate(s). The model considered has two nondegenerate minima at [Formula: see text], instead of one degenerate minimum at [Formula: see text]. The component fields of one SU(2) doublet ([Formula: see text]) act as the standard model (SM) Higgs, while the component fields of the second doublet ([Formula: see text]) are taken to be the dark energy candidates (lying in the true vacuum). It is found that one can arrange for late time acceleration (dark energy) by using an SU(2) Higgs doublet, whose vacuum expectation value is zero, in the quintessential regime.
AN APPROACH BASED ON LANDAUER–BÜTTIKER FORMALISM TO COMPUTE THE ELECTRONIC LOCALIZED STATES AT SURFACE BOUNDARIES
Authors: BELAYADI ADEL
Published: September 2019

In this contribution, we provide a theoretical model to study the effect of different cutting edges on the appearance of localized electronic states. The system under study is a three-dimensional atomic chain that ends with an open cut forming a semi-infinite structured layer in the (1 0 0), (1 1 0) and (1 1 1) directions. We investigate the surface electronic characteristics of the monoatomic chain of a simple cube (sc), orthorhombic (orth), and tetragonal (tetr) structures. We have adopted in our approach the tight-binding approximation to build up the surface Hamiltonian matrix. Additionally, the number of secular equation, at the surface, has been determined by using phase field matching theory (FPMT). In fact, the Hamiltonian system obtained from different cutting orientations provides an inhomogeneous system. To solve the surface eigenvalue problem, we integrate the calculation of the scattering reflection probabilities as given in Landauer–Büttiker formalism. Next, based on the computed scattering probabilities, we build up the surface core states which provide the surface Hamiltonian matrix which can be solved numerically. Our model calculation has been applied to the following elements: (i) fluorite (F), manganese (Mn), polonium (Po), bromine (Br), indium (I), tin (Sn), and protactinium (Pa). The results emphasize the influence of cutting direction on the electronic characteristic of surface and on the scale of energy values. We report the appearance of new electronic curves that characterize the surface states. Those surface states are localized down, within, and above the bulk spectrum. They also provide different characteristic features, of the metals under study, in a given cutting orientation. Furthermore, we have integrated the calculation of non-structured cuts on the outer layers. The relaxation effect on the surface is a standard process which leads to stabilize the changes in the internal energy until the equilibrium. The spacing geometry caused by the relaxation on the surface could be determined by using the molecular dynamic algorithm. We account in this case the lift of degeneracy and the rise of additional localized branches within and outside the bulk range.
Closed-Form Critical Buckling Load of Simply Supported Orthotropic Plates and Verification
Authors: Jing Zhao , Sun Qin , Liang Ke , Chen Jianqiao
Published: September 2019

The buckling mode is important to determine the critical load of specially orthotropic rectangular plates under axial compression with simply supported boundary. However, in classical laminated plate theory (CLPT), the critical buckling mode can only be obtained by iterative or numerical methods. This paper derives the critical buckling mode mathematically and presents the critical buckling load in closed form. By taking advantage of the derived closed-form solution, it is convenient to investigate the effects of aspect ratio, load ratio, and fiber orientation on the buckling load, and the parameters affecting the buckling mode can be easily obtained. The first-order shear deformation theory (FSDT)-based finite element method is developed to verify the closed-form solution. The bending-torsional coupling effects are analyzed and discussed to assess the approximation of the buckling behavior of specially orthotropic plates to general laminates. The obtained finite element solutions of general laminates are compared with the closed-form solutions of specially orthotropic plates. The accuracy of approximation of the buckling behavior of specially orthotropic plates to the general laminates increases as the bending-torsional coupling coefficients decrease. The closed-form solution can be applied to laminates with small bending-torsional coupling coefficients.
Torus quotient of Richardson varieties in orthogonal and symplectic grassmannians
Authors: Nayek Arpita , Pattanayak S. K.
Published: September 2019

For any simple, simply connected algebraic group [Formula: see text] of type [Formula: see text] and [Formula: see text] and for any maximal parabolic subgroup [Formula: see text] of [Formula: see text], we provide a criterion for a Richardson variety in [Formula: see text] to admit semistable points for the action of a maximal torus [Formula: see text] with respect to an ample line bundle on [Formula: see text].
On Newton polygons techniques and factorization of polynomials over Henselian fields
Authors: El Fadil Lhoussain
Published: September 2019

Let [Formula: see text] be a valued field, where [Formula: see text] is a rank-one discrete valuation, with valuation ring [Formula: see text]. The goal of this paper is to investigate some basic concepts of Newton polygon techniques of a monic polynomial [Formula: see text]; namely, theorem of the product, of the polygon, and of the residual polynomial, in such way that improves that given in [D. Cohen, A. Movahhedi and A. Salinier, Factorization over local fields and the irreducibility of generalized difference polynomials, Mathematika 47 (2000) 173–196] and generalizes that given in [J. Guardia, J. Montes and E. Nart, Newton polygons of higher order in algebraic number theory, Trans. Amer. Math. Soc. 364(1) (2012) 361–416] to any rank-one valued field.
Two-sided configuration equivalence and isomorphism
Authors: Malekan Meisam Soleimani , Rejali Ali
Published: September 2019

The concept of configuration was first introduced by Rosenblatt and Willis to give a characterization for the amenability of groups. Then Rejali and Yousofzadeh introduced the notion of two-sided configuration to study the normal subsets of a group. In [A, Abdollahi, A. Rejali and G. A. Willis, Group properties characterised by configurations, Illinois J. Math. 48(3) (2004) 861–873.], the authors have asked that if two configuration equivalent groups are isomorphic? We show that if [Formula: see text] and [Formula: see text] have same two-sided configuration sets and [Formula: see text] is a normal subgroup of [Formula: see text] with polycyclic or FC quotient, then there is a normal subgroup [Formula: see text] of [Formula: see text] such that [Formula: see text]. Also, we show that if [Formula: see text] and [Formula: see text] are two-sided equivalent groups, and if one of them is polycyclic or FC, then they are isomorphic.
Character correspondences in solvable groups with a self-normalizing sylow subgroup
Authors: Vallejo Rodríguez Carolina
Published: September 2019

Let [Formula: see text] be a finite solvable group and let [Formula: see text] for some prime [Formula: see text]. Whenever [Formula: see text] is odd, Isaacs described a correspondence between irreducible characters of degree not divisible by [Formula: see text] of [Formula: see text] and [Formula: see text]. This correspondence is natural in the sense that an algorithm is provided to compute it, and the result of the application of the algorithm does not depend on choices made. In the case where [Formula: see text], G. Navarro showed that every irreducible character [Formula: see text] of degree not divisible by [Formula: see text] has a unique linear constituent [Formula: see text] when restricted to [Formula: see text], and that the map [Formula: see text] defines a bijection. Navarro’s bijection is obviously natural in the sense described above. We show that these two correspondences are the same under the intersection of the hypotheses.
Quantitative properties of the non-properness set of a polynomial map, a positive characteristic case
Authors: Jelonek Zbigniew , Lasoń Michał
Published: September 2019

Let [Formula: see text] be a generically finite polynomial map of degree [Formula: see text] between affine spaces. In [Z. Jelonek and M. Lasoń, Quantitative properties of the non-properness set of a polynomial map, Manuscripta Math. 156(3–4) (2018) 383–397] we proved that if [Formula: see text] is the field of complex or real numbers, then the set [Formula: see text] of points at which [Formula: see text] is not proper is covered by polynomial curves of degree at most [Formula: see text]. In this paper, we generalize this result to positive characteristic. We provide a geometric proof of an upper bound by [Formula: see text].
Finsler spacetime geometry in physics
Authors: Pfeifer Christian
Published: September 2019

Finsler geometry naturally appears in the description of various physical systems. In this review, I divide the emergence of Finsler geometry in physics into three categories: dual description of dispersion relations, most general geometric clock and geometry being compatible with the relevant Ehlers–Pirani–Schild axioms. As Finsler geometry is a straightforward generalization of Riemannian geometry there are many attempts to use it as generalized geometry of spacetime in physics. However, this generalization is subtle due to the existence of non-trivial null directions. I review how a pseudo-Finsler spacetime geometry can be defined such that it provides a precise notion of causal curves, observers and their measurements as well as a gravitational field equation determining the Finslerian spacetime geometry dynamically. The construction of such Finsler spacetimes lays the foundation for comparing their predictions with observations, in astrophysics as well as in laboratory experiments.
Bis-palladium(II) complex of doubly N-confused octaphyrin(1.1.1.1.1.1.1.1): Möbius aromaticity and chiroptical properties
Authors: Basumatary Biju , Mitsuno Koki , Ishida Masatoshi , Furuta Hiroyuki
Published: September 2019

A novel bis-palladium(II) complex of doubly N-confused octaphyrin (Pd[Formula: see text]-2) adopting a Möbius-twisted topological structure was synthesized and characterized. Due to the effective 36[Formula: see text]-electronic delocalization over the Möbius-twisted octaphyrin scaffold, characteristic Soret and Q-like absorption features were observed in the near-infrared (NIR) region. However, the complex Pd[Formula: see text]-2 exhibited weak aromatic character attributed to the distinct cross-conjugated resonance contribution as inferred from the 1H NMR chemical shifts as well as theoretical assessments ([Formula: see text] nucleus-independent chemical shift (NICS)). Since the bis-palladium(II) complexation of doubly N-confused octaphyrin 2 imparted significant conformational stability, topologically chiral enantiomers of Pd[Formula: see text]-2 were successfully separated as ([Formula: see text]- and ([Formula: see text]-twisted forms. The resulting isomers revealed relatively large circular dichroism (CD) responses with an absorption anisotropy factor of [Formula: see text] [Formula: see text] 0.009 in the NIR region ([Formula: see text] 823 nm). In addition, the cyclic voltammogram of Pd[Formula: see text]-2 revealed redox-rich properties due to its large [Formula: see text]-conjugated system.
Enhanced photochromism of silver bromide/polyvinylpyrrolidone film doped with noble metal ions and its application on rewritable paper with erasure without heating or oxygen
Authors: Cao Yaxing , Chen Hongling
Published: September 2019

Ink-free printing and rewritable paper have attracted great attention as a potential alternative to current paper prints. Herein, a kind of novel rewritable paper based on silver bromide (AgBr)/polyvinylpyrrolidone (PVP) hybrids is reported, and the system can be erased in dark without heating or oxygen due to the presence of [Formula: see text]. The preparation temperature showed significant effect on the morphology and size of AgBr crystal. When the preparation temperature at 60∘C, the AgBr crystal demonstrated a spherical structure with a size of 0.075[Formula: see text][Formula: see text]m, and the film showed transparency. The addition of noble metal ions can significantly increase the sensitivity to UV irradiation, and the optimum concentration of [Formula: see text] ion was [Formula: see text] M for the reversible property of the rewritable paper. After ten writing–erasing cycles, the repeatable writing performance changed little. With prolonged UV illumination, the erasing time of rewritable paper became longer, and even up to one week, showing great potential for practical applications.
Terrain Amplification with Implicit 3D Features
Authors: Paris Axel , Galin Eric , Peytavie Adrien , Guérin Eric , Gain James
Published: September 2019

While three-dimensional landforms, such as arches and overhangs, occupy a relatively small proportion of most computer-generated landscapes, they are distinctive and dramatic and have an outsize visual impact. Unfortunately, the dominant heightfield representation of terrain precludes such features, and existing in-memory volumetric structures are too memory intensive to handle larger scenes.

In this article, we present a novel memory-optimized paradigm for representing and generating volumetric terrain based on implicit surfaces. We encode feature shapes and terrain geology using construction trees that arrange and combine implicit primitives. The landform primitives themselves are positioned using Poisson sampling, built using open shape grammars guided by stratified erosion and invasion percolation processes, and, finally, queried during polygonization. Users can also interactively author landforms using high-level modeling tools to create or edit the underlying construction trees, with support for iterative cycles of editing and simulation.

We demonstrate that our framework is capable of importing existing large-scale heightfield terrains and amplifying them with such diverse structures as slot canyons, sea arches, stratified cliffs, fields of hoodoos, and complex karst cave networks.
FRoC 2.0
Authors: Ahmed Ibrahim , Zhao Shuze , Meijers James , Trescases Olivier , Betz Vaughn
Published: September 2019

In earlier technology nodes, FPGAs had low power consumption compared to other compute chips such as CPUs and GPUs. However, in the 14nm technology node, FPGAs are consuming unprecedented power in the 100+W range, making power consumption a pressing concern. To reduce FPGA power consumption, several researchers have proposed deploying dynamic voltage scaling. While the previously proposed solutions show promising results, they have difficulty guaranteeing safe operation at reduced voltages for applications that use the FPGA hard blocks. In this work, we present the first DVS solution that is able to fully handle FPGA applications that use BRAMs. Our solution not only robustly tests the soft logic component of the application but also tests all components connected to the BRAMs. We extend a previously proposed CAD tool, FRoC, to automatically generate calibration bitstreams that are used to measure the application’s critical path delays on silicon. The calibration bitstreams also include testers that ensure all used SRAM cells operate safely while scaling V
dd
. We experimentally show that using our DVS solution we can save 32% of the total power consumed by a discrete Fourier transform application running with the fixed nominal supply voltage and clocked at the F
max
reported by static timing analysis.
Blind Stereo Image Quality Evaluation Based on Convolutional Network and Saliency Weighting
Authors: Zhou Wujie
Published: September 2019

With the rapid development of stereo image applications, there is an increasing demand to develop a versatile tool to evaluate the perceived quality of stereo images. Therefore, in this study, a blind stereo image quality evaluation (SIQE) algorithm based on convolutional network and saliency weighting is proposed. The main network framework used by the algorithm is the quality map generation network, which is used to train the distortion image dataset and quality map label to obtain an optimal network framework. Finally, the left view, right view, and cyclopean view of the stereo image are used as inputs to the network frame, respectively, and then weighted fusion for the final stereo image quality score. The experimental results reveal that the proposed SIQE algorithm can improve the accuracy of the image quality prediction and prediction score to a certain extent and has good generalization ability.
Adiponectin Expression Is Modulated by Long-Term Physical Activity in Adult Patients Affected by Cystic Fibrosis
Authors: Polito Rita , Nigro Ersilia , Elce Ausilia , Monaco Maria Ludovica , Iacotucci Paola , Carnovale Vincenzo , Comegna Marika , Gelzo Monica , Zarrilli Federica , Corso Gaetano , Castaldo Giuseppe , Daniele Aurora
Published: September 2019

Cystic fibrosis (CF) is a genetic disease characterized by progressive decline of lung function and chronic airway inflammation. Adipose tissue, through adiponectin and leptin, exerts several effects on energy metabolism and inflammatory processes. This study evaluated the levels of adiponectin and leptin in adult healthy subjects, in patients with CF and their correlation with long-term physical activity. CF patients were divided into two groups (sedentary versus active) based on their regular physical activity over 3 years. Anthropometric and serum biochemical profiles of CF patients and controls were evaluated and compared. Total serum adiponectin and leptin levels were measured by ELISA; adiponectin oligomeric profiles were analysed by western blot. Adiponectin levels were significantly higher while leptin levels were lower in patients with CF than in healthy controls. Furthermore, adiponectin was significantly lower in active compared to sedentary CF (p=0.047), while leptin was slightly increased in active compared to sedentary CF. In addition, C-reactive protein levels were significantly lower in active than in sedentary CF patients (p=0.048). Interestingly, only in the active group adiponectin levels were inversely correlated with forced expiratory volume (FEV) 1% decrease/year and FEV1% decrease. Moreover, adiponectin levels negatively correlated with lipid profiles. Our findings indicated that regular, long-term physical activity in CF improves respiratory function, metabolism, and inflammation status. These improvements in patients’ conditions are associated with immunometabolic processes involving adiponectin, leptin, and C-reactive protein. Therefore, we propose that both adipokines may be a useful biomarker in the evaluation of metabolic and inflammatory status in patients with CF.
Estimating Salt Concentrations Based on Optimized Spectral Indices in Soils with Regional Heterogeneity
Authors: Kahaer Yasenjiang , Tashpolat Nigara
Published: September 2019

Soil salinity is one of the most damaging environmental problems worldwide, especially in arid and semiarid regions. The objectives of this study were to improve the inversion accuracy of soil salt content (SSC) in soils with spectral heterogeneity by using optimized spectral indices. Soil samples at a 0–20 cm depth were taken from Keriya Oasis (98 soil samples), Ugan-Kuqa Oasis (49 soil samples), and Ebinur Lake Basin (57 soil samples). SSC and spectral reflectance (SR) of all the 204 soil samples were determined. To comprehensively analyze the field-collected hyperspectral data, various band combinations were used to calculate a normalized difference spectral index (NDSI) and ratio spectral index (RSI). Then, the relationships between the indices and SSC were examined, and the most robust relationships were demonstrated. The partial least squares regression (PLSR) method was utilized to develop a predictive model of SSC, and the variable importance in the projection (VIP) method was used during modeling. The results revealed that (i) the salinized soils in different regions had apparent differences in both reflectance and spectral curve morphology, but the optimized spectral indices method effectively overcame the regional heterogeneity of salinized soil hyperspectral characteristics, and the correlation with SSC was always kind, with correlation coefficients up to 0.748 at 0.001 level of significance; (ii) the VIP filtering method effectively selected the optimal independent model, and the modeling accuracy was better than the single optimization index (R2Pre = 0.83 and RMSEPre = 2.31 g·kg−1) by using the combination of two optimal indices; (iii) although the global modeling accuracy was significantly lower than the local modeling accuracy due to the inconsistent salt sensitivity bands of salinized soils in different regions, combined with cross-validation analysis, the global model had the ability to predict soil salinization accurately (R2Pre = 0.69 and RMSEPre = 8.45 g·kg−1). The methods developed in this study can be applied in other arid and semiarid areas. Besides, the study also provides examples for aerospace hyperspectral remote sensing of cross-regional soil salinization.
ART Regimen and Other Sociodemographics Do Not Affect Cytokine Expression in HIV Patients in Ghana
Authors: Essien-Baidoo Samuel , Obiri-Yeboah Dorcas , Opoku Yeboah Kwaku , Ayamga Elvis , Hodi Zie Kevin , Attoh Daniel , Obboh Evans , Hayfron Benjamin Anna , Afrifa Justice
Published: September 2019

Background. HIV infection is marked by the production of cytokines by infected cells and cells of the immune system. Variations in the levels of cytokine in HIV-infected individuals significantly impact the role of the immune system with the possibility to affect the course of HIV disease by either exacerbating or suppressing HIV replication. Aim. The study sought to investigate the effect of sociodemographic indices, clinical laboratory parameters, and ART regimen on Th1, Th2, and Th17 cytokines in HIV patients. Materials and methods. A total of two hundred (200) HIV patients on either the first or second line of ART were recruited into the study. Sociodemographic indices were collected using researcher-administered questionnaires. Serum concentrations of two major immune-promoting cytokines, IL-12 and IFN-γ, and immune-suppressive cytokines, IL-10 and IL-17, were measured using enzyme-linked immunosorbent assay (ELISA). T-test and chi-square were used to compare mean scores, while correlation (Pearson’s correlation) and linear regression analyses were also performed with the statistical significance set at p<0.05. Results. The mean age of the participants was (45.54 ± 0.7846) years with a greater proportion (84.5%) between 31 and 60 years. The mean interferon-gamma (INF-γ), interleukin- (IL-) 10, interleukin-12, and interleukin-17 were estimated to be 349.9 ± 8.391 pg/ml, 19.32 ± 0.4593 pg/ml, 19.23 ± 0.3960 pg/ml, and 24.6 ± 0.6207 pg/ml, respectively. Although INF-γ and IL-17 levels were relatively higher in males compared to females, it was vice versa for IL-10 and IL-12. However, none of these was statistically significant. Again, no significant difference was observed among all the cytokines stratified by the duration of ART, stage of HIV, and smoking status. Most importantly, stratification by either first- or second-line ART regimens recorded no significant difference in cytokine levels. Age significantly correlated inversely with IFN-γ (r = −0.27, p≤0.001), IL-10 (r = −0.24, p≤0.001), and IL-12 (r = −0.18, p=0.01) while duration on ART significantly correlated inversely with IFN-γ (r = −0.16, p=0.02). CD4 counts at 6 months and 12 months on ART correlated inversely with IL-17 (r = −0.17, p=0.02) and plasma viral load at 1 year (r = −0.22, p≤0.001), respectively. A positive correlation was observed between IFN-γ and IL-12 (r = −0.84, p≤0.001) and IL-17 (r = −0.50, p≤0.001). This positive trend was repeated between IL-10 and IL-12 (r = −0.92, p≤0.001) and IL-17 (r = −0.61, p≤0.001). Conclusion. The levels of IFN-γ, IL-12, IL-17, and IL-10 are not significantly affected by sociodemographics and ART regimen. This observation shows that no significant difference was observed in cytokine levels stratified by ART regiments. This means that both regimens are effective in the suppression of disease progression.
Simultaneous Analysis of Twelve Bile Acids by UPLC-MS and Exploration of the Processing Mechanism of Bile Arisaema by Fermentation
Authors: Zhao Qimiao , Shan Guoshun , Xu Dan , Gao Hui , Shi Ji , Ju Chengguo , Lin Guimei , Zhang Fan , Jia Tianzhu
Published: September 2019

Ultrahigh-performance liquid chromatography (UPLC) coupled with quadrupole time-of-flight tandem mass spectrometry (Q/TOF-MS) in the MS/MS mode and UPLC coupled with triple quadrupole mass spectrometry (QqQ-MS) using the multiple reaction monitoring (MRM) mode were used to make a qualitative and quantitative analysis of twelve bile acids in Bile Arisaema. The fragmentation pathway of twelve bile acids was proposed. The quantification method showed a good linearity over a wide concentration range (R2 > 0.99), repeatability (RSD < 4.12%), stability (RSD < 4.25%), precision (RSD < 4.06%), and recovery (95.36–102.15%). Content of twelve compounds in Bile Arisaema varied significantly depending on region. Chemometric methods, hierarchical clustering analysis (HCA), and principal components analysis (PCA) were successfully used to optimize the fermentation time of the Bile Arisaema. The results suggested that the Bile Arisaema could complete fermentation in 15 days. The possible processing mechanism of Bile Arisaema promoted the transformation of conjugated bile acids into free bile acids in fermentation.
A Meta-Analysis of the Efficacy of Prokinetic Agents against Glycemic Control
Authors: Kim Yeon-Ji , Chung Woo Chul , Lee Seung Jae
Published: September 2019

Background. Prokinetic agents are used in diabetic gastroparesis patients to improve gastric emptying and upper gastrointestinal (GI) symptoms. However, the efficacy of prokinetic agents against glycemic control is questionable. Therefore, we conducted a systemic review and meta-analysis to determine the efficacy of prokinetic agents against glycemic control. Methods. Randomized controlled trials (RCTs) evaluating the effect of prokinetics were identified by searching PubMed, Embase, and the Cochrane Library databases until April 2018. The primary outcome was changes in the mean value of glycosylated hemoglobin (HbA1c), fasting blood sugar (FBS), and fasting serum insulin (FINS). The pooled standardized mean differences (SMD) with 95% confidence intervals (CIs) were calculated by evaluating the strength of the association. We used the random effect models to analyze these markers. The effects of each component of the prokinetic agents on glycemic control were separately analyzed. Results. Five RCTs with 190 patients met the criteria and were included in the meta-analysis. There were statistically significant SMD between prokinetics and placebo-controlled groups with respect to the reduction of HbA1c (-1.141, 95% CI -1.843, -0.438; P<0.01). No statistically significant differences were noted between the two groups for FBS (-1.270, 95% CI -2.613, -0.074; P=0.06) and FINS (0.359, 95% CI -1.205~1.923; P=0.65). Conclusions. Prokinetics have a positive effect on glycemic control. Further large-scale prospective studies are needed.
A New Plant Indicator (Artemisia lavandulaefolia DC.) of Mercury in Soil Developed by Fourier-Transform Near-Infrared Spectroscopy Coupled with Least Squares Support Vector Machine
Authors: Xu Lu , Shi Qiong , Tang Bang-Cheng , Xie Shunping
Published: September 2019

A rapid indicator of mercury in soil using a plant (Artemisia lavandulaefolia DC., ALDC) commonly distributed in mercury mining area was established by fusion of Fourier-transform near-infrared (FT-NIR) spectroscopy coupled with least squares support vector machine (LS-SVM). The representative samples of ALDC (stem and leaf) were gathered from the surrounding and distant areas of the mercury mines. As a reference method, the total mercury contents in soil and ALDC samples were determined by a direct mercury analyzer incorporating high-temperature decomposition, catalytic adsorption for impurity removal, amalgamation capture, and atomic absorption spectrometry (AAS). Based on the FT-NIR data of ALDC samples, LS-SVM models were established to distinguish mercury-contaminated and ordinary soil. The results of reference analysis showed that the mercury level of the areas surrounding mercury mines (0–3 kilometers, 7.52–88.59 mg/kg) was significantly higher than that of the areas distant from mercury mines (>5 kilometers, 0–0.75 mg/kg). The LS-SVM classification model of ALDC samples was established based on the original spectra, smoothed spectra, second-derivative (D2) spectra, and standard normal transformation (SNV) spectra, respectively. The prediction accuracy of D2-LS-SVM was the highest (0.950). FT-NIR combined with LS-SVM modeling can quickly and accurately identify the contaminated ALDC. Compared with traditional methods which rely on naked eye observation of plants, this method is objective and more sensitive and applicable.
The Association between Helicobacter pylori Infection and Glycated Hemoglobin A in Diabetes: A Meta-Analysis
Authors: Chen Jinhu , Xing Yuling , Zhao Liying , Ma Huijuan
Published: September 2019

Background.The association between Helicobacter pylori infection and glycated hemoglobin A has been confirmed in many studies, but these conclusions are still contradictory and controversial. Therefore, we conducted a meta-analysis to resolve the problem of inconsistent results in diabetes.Methods. A comprehensive search was conducted on related researches published in PubMed, Embase, and China Academic Journal Full-text Database (CNKI) from the inception of each database to April 2019. Fixed or random effects model was used to pool the weighted mean difference with 95% confidence interval from individual studies. Subgroup and sensitivity analyses were also performed. Publication bias was estimated by funnel plot, Egger’s test, and fail-safe numbers.Results. 35 studies with 4,401 participants with diabetes were included in the meta-analysis. Glycated hemoglobin A levels were elevated in patients with Helicobacter pylori infection compared with patients without Helicobacter pylori infection (WMD=0.50, 95% CI: 0.28-0.72,p<0.001). In subgroup analysis by the subtype of diabetes, there was a correlation between Helicobacter pylori infection and elevated glycated hemoglobin A in type 1 diabetes (I2=74%,p<0.001,WMD=0.46, 95% CI: 0.12-0.80), and in type 2 diabetes (I2=90%,p<0.001,WMD=0.59, 95% CI: 0.28-0.90,p<0.001). In subgroup analysis by the study design, there was a correlation in cross-sectional study (I2=89%,p<0.001,WMD=0.42, 95% CI: 0.16-0.69,p≤0.003) and in case-control study (I2=83%,p<0.001,WMD=0.39, 95% CI: 0.14-0.64,p≤0.003). By different methods for detecting Helicobacter pylori, there was a correlation in the biopsy group (I2=83%,p<0.001,WMD=0.6, 95% CI: 0.11-1.09,p≤0.03) and in other groups of test methods (I2=87%,p<0.001,WMD=0.37, 95% CI: 0.17-0.56,p<0.001). Sensitivity analysis showed that our results were reliable, and no evidence of substantial publication bias was detected.Conclusion. The meta-analysis might indicate a correlation between Helicobacter pylori infection and glycated hemoglobin A levels in diabetes.
Anthropometric Parameters in Celiac Disease: A Review on the Different Evaluation Methods and Disease Effects
Authors: Costa Allysson , Brito Gleisson A. P.
Published: September 2019

This review compiled anthropometric data from 29 original articles, published between 1995 and 2015, corresponding to a total sample of 6368 celiac disease subjects. Body mass index was the main parameter for measuring anthropometry (82.1%), followed by body mass (78.6%), body fat (51.7%), bone mineral density and bone mineral content (46.4%), and fat-free mass (44.8%). The main evaluation method was dual x-ray absorptiometry (83.3%), followed by bioimpedance (16.6%), skinfold thickness (16.6%), and isotope dilution (5.5%). This compilation suggests that celiac disease patients without a gluten-free diet (WGFD) and celiac disease patients with a gluten-free diet (GFD) show a lower body mass than the control group, with inconclusive data about WGFD versus GFD. Body mass index is lower in WGFD and GFD compared to control group, and is lower in WGFD compared to GFD. We observed lower values of FM and FFM in WGFD and GFD versus the control group. No difference was found between WGFD versus GFD. BMD and BMC are lower in WGFD versus GFD and GFD versus the control group, with inconclusive data about WGFD versus GFD. The findings of this review suggest that celiac disease patients must be periodically evaluated through anthropometric parameters, since the pathology has the potential to modulate such values even in a gluten-free diet, with these variables reflecting their healthy status. In parallel, the screening of different anthropometric assessment methodologies can provide support for more accurate evaluations by scientists and clinical professionals who work with celiac disease patients.
A Loading Dose of IV Salbutamol in an Adolescent with Severe Acute Asthma and Cardiac Arrest
Authors: Boeschoten Shelley A. , van der Crabben Ruben S. , Boehmer Annemie L. M. , de Hoog Matthijs , Buysse Corinne M. P.
Published: September 2019

Severe acute asthma (SAA) can lead to respiratory failure and can be fatal. For rational use of intravenous (IV) bronchodilators, evidence regarding the pharmacokinetics and pharmacodynamics is lacking in children. The use of a loading dose IV salbutamol is not mentioned in any international guideline, and its use varies greatly between PICUs worldwide. We describe a 17-year-old Caucasian female with SAA resulting in an out-of-hospital cardiac arrest. After basic life support and return of spontaneous circulation, the ambulance administered oxygen, inhaled salbutamol, IV magnesium sulphate, and systemic corticosteroids. Despite of this, she was still in severe respiratory distress. Therefore, a loading dose of IV salbutamol was administered, after which an immediate improvement was observed. Having a loading dose of IV salbutamol available for emergency medical services use for SAA in children with life-threatening SAA in the out-of-hospital setting is important to consider. Further study on the dose and the effect of a loading dose IV salbutamol in children with SAA is necessary.
An Unusual Cause of Bleeding in a Patient with Chronic Myeloid Leukemia Chronic Phase
Authors: Kartthik S. , Mandal Prakas K. , Abdullah Saleh Mohammed
Published: September 2019

Chronic myelogenous leukemia (CML) is a clonal myeloproliferative neoplasm (MPN) characterized by dysregulated and uncontrolled proliferation of mature and maturing granulocytes with normal differentiation. A genetic hallmark of CML is the presence of the fusion gene product BCR-ABL. Bleeding diathesis in CML patients is rare (<10%) and primarily caused by acquired platelet dysfunction. We report a rare case of an adult CML chronic phase patient who presented with spontaneous muscle hematoma due to acquired Glanzmann’s thrombasthenia (GT). On laboratory workup, a GT was confirmed along with the diagnosis of CML in chronic phase. The muscle hematoma was completely resolved following imatinib therapy. The present case demonstrates that bleeding is a complication of MPNs and highlights the importance of both acquired GT diagnosis to determine the cause of bleeding in CML and of prompt treatment with imatinib to reverse this condition.
A Chinese Family with Familial Dysalbuminemic Hyperthyroxinemia (FDH) due to R242H Mutation on Human Albumin Gene: Reevaluating the Role of FDH in Patients with Asymptomatic Hyperthyroxinemia
Authors: Liu Hongbing , Ran Jianmin , Chen Chuping , Chen Guangshu , Zhu Ping , Tan Rongshao , Liu Yan
Published: September 2019

Objective. Familial dysalbuminemic hyperthyroxinemia (FDH) has now become an established cause for spurious asymptomatic hyperthyroxinemia. Several different codon mutations on albumin gene had been identified. We here provided an established but rarely reported heterozygous mutation based on gene sequencing results from a Chinese family.Methods. The proband is a 14-year-old girl with light goiter and asymptomatic clinical presentations, whose thyroid function test by a one-step immunoassay showed increased free thyroxine (FT4) and free triiodothyronine (FT3) but nonsuppressed thyrotropin (TSH). All thyroid auto-antibodies were in the normal range. Blood samples were collected from her and most of her immediate family members for target gene sequencing and verification.Results. Hyperthyroxinemia was also confirmed in the proband’s mother and one of her uncles and his son. In the proband and these three pedigrees, the high-throughput gene screening sequencing and the following Sanger sequencing disclosed a heterozygous mutation in the albumin gene, which located in its exon 7 (c.725G > A), and correspondingly leads to an arginine replacement with a histidine (R242H) in its protein. This is an established mutation named as R218H if present without signal peptide sequence.Conclusions. For patients with asymptomatic hyperthyroxinemia, FDH should be clinically excluded before embarking on further investigations for other specific causes.