bluuebunny/crossref_metadata_2025 huggingface dataset:
Stochastic-Petri Net Modeling and Optimization for Outdoor Patients in Building Sustainable Healthcare System Considering Staff Absenteeism
Authors: Kang Chang Wook , Imran Muhammad , Omair Muhammad , Ahmed Waqas , Ullah Misbah , Sarkar Biswajit
Published: June 2019

Sustainable healthcare systems are gaining more importance in the era of globalization. The efficient planning with sustainable resources in healthcare systems is necessary for the patient’s satisfaction. The proposed research considers performance improvement along with future sustainability. The main objective of this study is to minimize the queue of patients and required resources in a healthcare unit with the consideration of staff absenteeism. It is a resource-planning model with staff absenteeism and operational utilization. Petri nets have been integrated with a mixed integer nonlinear programming model (MINLP) to form a new approach that is used as a solution method to the problem. The Petri net is the combination of graphical, mathematical technique, and simulation for visualizing and optimization of a system having both continuous and discrete characteristics. In this research study, two cases of resource planning have been presented. The first case considers the planning without absenteeism and the second incorporates planning with the absenteeism factor. The comparison of both cases showed that planning with the absenteeism factor improved the performance of healthcare systems in terms of the reduced queue of patients and improved operational sustainability.
Generalized Mittag–Leffler Stability of Hilfer Fractional Order Nonlinear Dynamic System
Authors: Wang Guotao , Qin Jianfang , Dong Huanhe , Guan Tingting
Published: June 2019

This article studies the generalized Mittag–Leffler stability of Hilfer fractional nonautonomous system by using the Lyapunov direct method. A new Hilfer type fractional comparison principle is also proved. The novelty of this article is the fractional Lyapunov direct method combined with the Hilfer type fractional comparison principle. Finally, our main results are explained by some examples.
The Regularity of Solution for Weakly Coupled System Derived by Microwave Heating Model
Authors: Liao Yumei , Wei Wei
Published: June 2019

In this paper, we study the regularity of the weak solution of the coupled system derived from the microwave heating model with frequency variable. We first show that the weak solution E of the system is Hölder continuous near the boundary of S = ∂ Ω . The main idea of the proof is based on the estimation of linear degenerate system in Campanato space. Then we show that the solution u of the heat conduction equation is Hölder continuous with exponent α 2 . Finally, under the appropriate conditions we show that the coupled system with microwave heating has a weak solution. Moreover the regularity of the weak solution is studied.
Non-Parametric Threshold Estimation for the Wiener–Poisson Risk Model
Authors: You Honglong , Gao Yuan
Published: June 2019

In this paper, we consider the Wiener–Poisson risk model, which consists of a Wiener process and a compound Poisson process. Given the discrete record of observations, we use a threshold method and a regularized Laplace inversion technique to estimate the survival probability. In addition, we also construct an estimator for the distribution function of jump size and study its consistency and asymptotic normality. Finally, we give some simulations to verify our results.
Some New Higher Order Weighted Newton Methods for Solving Nonlinear Equation with Applications
Authors: Sivakumar Parimala , Jayaraman Jayakumar
Published: June 2019

Three new iterative methods for solving scalar nonlinear equations using weight function technique are presented. The first one is a two-step fifth order method with four function evaluations which is improved from a two-step Newton’s method having same number of function evaluations. By this, the efficiency index of the new method is improved from 1.414 to 1.495. The second one is a three step method with one additional function evaluation producing eighth order accuracy with efficiency index 1.516. The last one is a new fourth order optimal two-step method with efficiency index 1.587. All these three methods are better than Newton’s method and many other equivalent higher order methods. Convergence analyses are established so that these methods have fifth, eighth and fourth order respectively. Numerical examples ascertain that the proposed methods are efficient and demonstrate better performance when compared to some equivalent and optimal methods. Seven application problems are solved to illustrate the efficiency and performance of the proposed methods.
In Vitro Studies Reveal Antiurolithic Effect of Antioxidant Sulfated Polysaccharides from the Green Seaweed Caulerpa cupressoides var flabellata
Authors: Gomes Dayanne Lopes , Melo Karoline Rachel Teodosio , Queiroz Moacir Fernandes , Batista Lucas Alighieri Neves Costa , Santos Pablo Castro , Costa Mariana Santana Santos Pereira , Almeida-Lima Jailma , Camara Rafael Barros Gomes , Costa Leandro Silva , Rocha Hugo Alexandre Oliveira
Published: June 2019

Urolithiasis affects approximately 10% of the world population and is strongly associated with calcium oxalate (CaOx) crystals. Currently, there is no efficient compound that can be used to prevent this disease. However, seaweeds’ sulfated polysaccharides (SPs) can change the CaOx crystals surface’s charge and thus modify the crystallization dynamics, due to the interaction of the negative charges of these polymers with the crystal surface during their synthesis. We observed that the SPs of Caulerpa cupressoides modified the morphology, size and surface charge of CaOx crystals. Thus, these crystals became similar to those found in healthy persons. In the presence of SPs, dihydrate CaOx crystals showed rounded or dumbbell morphology. Infrared analysis, fluorescence microscopy, flow cytometry (FITC-conjugated SPs) and atomic composition analysis (EDS) allowed us to propose the mode of action between the Caulerpa’s SPs and the CaOx crystals. This study is the first step in understanding the interactions between SPs, which are promising molecules for the treatment of urolithiasis, and CaOx crystals, which are the main cause of kidney stones.
Prebiotics from Seaweeds: An Ocean of Opportunity?
Authors: Cherry Paul , Yadav Supriya , Strain Conall R. , Allsopp Philip J. , McSorley Emeir M. , Ross R. Paul , Stanton Catherine
Published: June 2019

Seaweeds are an underexploited and potentially sustainable crop which offer a rich source of bioactive compounds, including novel complex polysaccharides, polyphenols, fatty acids, and carotenoids. The purported efficacies of these phytochemicals have led to potential functional food and nutraceutical applications which aim to protect against cardiometabolic and inflammatory risk factors associated with non-communicable diseases, such as obesity, type 2 diabetes, metabolic syndrome, cardiovascular disease, inflammatory bowel disease, and some cancers. Concurrent understanding that perturbations of gut microbial composition and metabolic function manifest throughout health and disease has led to dietary strategies, such as prebiotics, which exploit the diet-host-microbe paradigm to modulate the gut microbiota, such that host health is maintained or improved. The prebiotic definition was recently updated to “a substrate that is selectively utilised by host microorganisms conferring a health benefit”, which, given that previous discussion regarding seaweed prebiotics has focused upon saccharolytic fermentation, an opportunity is presented to explore how non-complex polysaccharide components from seaweeds may be metabolised by host microbial populations to benefit host health. Thus, this review provides an innovative approach to consider how the gut microbiota may utilise seaweed phytochemicals, such as polyphenols, polyunsaturated fatty acids, and carotenoids, and provides an updated discussion regarding the catabolism of seaweed-derived complex polysaccharides with potential prebiotic activity. Additional in vitro screening studies and in vivo animal studies are needed to identify potential prebiotics from seaweeds, alongside untargeted metabolomics to decipher microbial-derived metabolites from seaweeds. Furthermore, controlled human intervention studies with health-related end points to elucidate prebiotic efficacy are required.
Butenolide Derivatives with α-Glucosidase Inhibitions from the Deep-Sea-Derived Fungus Aspergillus terreus YPGA10
Authors: Cheng Zhongbin , Li Yuanli , Liu Wan , Liu Lijun , Liu Jie , Yuan Wangjun , Luo Zhuhua , Xu Wei , Li Qin
Published: June 2019

Three new butenolide derivatives, namely aspernolides N–P (1–3), together with six known analogues (4–9), were isolated from the ethyl acetate (EtOAc) extract of the deep sea-derived fungus Aspergillus terreus YPGA10. The structures of compounds 1–3 were determined on the basis of comprehensive analyses of the nuclear magnetic resonance (NMR) and mass spectroscopy (MS) data, and the absolute configurations of 1 and 2 were determined by comparisons of experimental electronic circular dichroism (ECD) with calculated ECD spectra. Compound 1 represents the rare example of Aspergillus-derived butenolide derivatives featured by a monosubstituted benzene ring. Compounds 6–9 exhibited remarkable inhibitory effects against α-glucosidase with IC50 values of 3.87, 1.37, 6.98, and 8.06 μM, respectively, being much more active than the positive control acarbose (190.2 μM).
Immunoinformatics Based Study of T Cell Epitopes in Zea m 1 Pollen Allergen
Authors: Basu Anamika
Published: June 2019

Background and Objectives: Zea m 1 is a pollen allergen, which is present in maize, is accountable for a type I hypersensitivity reaction in all over the world. Several effective medications are available for the disorder with various side effects. Design and verification of a peptide-based vaccine is a state-of-art technology which is more cost effective than conventional drugs. Materials and Methods: Using immunoinformatic methods, the T cell epitopes from the whole structure of this allergenic protein can be predicted. Worldwide conserved region study among the other pollen allergens has been performed for T cell predicted epitopes by using a conservancy tool. This analysis will help to identify completely conserved HLA (human leukocyte antigen) binding epitopes. Lastly, molecular docking study and MHC-oligopeptide complex binding energy calculation data are applied to determine the interacting amino acids and the affinity of the epitopes to the class II MHCmolecule. Results: The study of criteria-based analysis predicts the presence of two epitopes YVADDGDIV and WRMDTAKAL on this pollen allergen. Conclusions: The T cell epitopes identified in this study provide insight into a peptide-based vaccine for a type I hypersensitivity reaction induced by Zea m 1 grass pollen allergenic protein.
Morphological Stages of Mitochondrial Vacuolar Degeneration in Phenylephrine-Stressed Cardiac Myocytes and in Animal Models and Human Heart Failure
Authors: Chaanine Antoine H.
Published: June 2019

Background and objectives: Derangements in mitochondrial integrity and function constitute an important pathophysiological feature in the pathogenesis of heart failure (HF) and play an important role in myocardial remodeling and systolic dysfunction. In systolic HF, we and others have shown an imbalance in mitochondrial dynamics toward mitochondrial fission and fragmentation with evidence of mitophagy, mitochondrial vacuolar degeneration, and impairment in mitochondrial oxidative capacity. The morphological stages of mitochondrial vacuolar degeneration have not been defined. We sought to elucidate the progressive stages of mitochondrial vacuolar degeneration, which would serve as a measure to define, morphologically, the severity of mitochondrial damage. Materials and Methods: Transmission electron microscopy was used to study mitochondrial morphology and pathology in phenylephrine-stressed cardiac myocytes in vitro and in left ventricular myocardium from a rat model of pressure overload induced systolic dysfunction and from patients with systolic HF. Results: In phenylephrine-stressed cardiomyocytes for two hours, alterations in mitochondrial cristae morphology (Stage A) and loss and dissolution of mitochondrial cristae in one (Stage B) or multiple (early Stage B→C) mitochondrion area(s) were evident in the earliest stages of mitochondrial vacuolar degeneration. Mitochondrial swelling and progressive dissolution of mitochondrial cristae (advanced Stage B→C), followed by complete loss and dissolution of mitochondrial cristae and permeabilization and destruction of inner mitochondrial membrane (Stage C) then outer mitochondrial membrane rupture (Stage D) constituted advanced stages of mitochondrial vacuolar degeneration. Similar morphological changes in mitochondrial vacuolar degeneration were seen in vivo in animal models and in patients with systolic HF; where about 60–70% of the mitochondria are mainly observed in stages B→C and fewer in stages C and D. Conclusion: Mitochondrial vacuolar degeneration is a prominent mitochondrial morphological feature seen in HF. Defining the progressive stages of mitochondrial vacuolar degeneration would serve as a measure to assess morphologically the severity of mitochondrial damage.
Left Atrial Function Is Improved in Short-Term Follow-Up after Catheter Ablation of Outflow Tract Premature Ventricular Complexes
Authors: Kanat Selçuk , Mutluer Ferit Onur , Tütüncü Ahmet , Duran Karaduman Bilge , Bozkaya Veciha Ozlem , Keskin Muhammed , Uslu Abdulkadir , Çay Serkan , Tenekecioglu Erhan
Published: June 2019

Background: Association of premature ventricular complexes (PVC) with left ventricular systolic dysfunction (LVSD) and efficacy of catheter ablation treatment have been demonstrated in studies. The role of left atrial (LA) mechanics in the etiopathogenesis of PVC-induced cardiomyopathy (PVC-CMP) as well as changes in LA mechanics with catheter ablation have not been studied before. Methods: A total number of 61 patients (Mean Age 43 ± 3) with idiopathic outflow tract (OT) PVCs undergoing radiofrequency catheter ablation (RFCA) were enrolled. ECG, 24 h Holter, and echocardiographic evaluation with left ventricular (LV) diastolic functions and LA volumetric assessments were performed before and three months after RFCA. Results: Along with a marginal increase in left ventricle ejection fraction (LVEF), improvement in diastolic functions and left atrial mechanics were observed in the study (LVEF 53 ± 7 versus 57 ± 6, p < 0.01) in short-term follow-up. The frequency of LV diastolic dysfunction (LVDD) decreased with catheter ablation (n = 5 to 0, p = 0.02). The overall LA function improved. Left atrium passive and overall emptying fraction (LAEF) increased significantly (0.32 ± 0.04 to 0.41 ± 0.04, p < 0.05 and 0.62 ± 0.04 to 0.65 ± 0.004, p < 0.05, respectively). Active LAEF decreased significantly (0.29 ± 0.005 to 0.24 ± 0.006, p < 0.05). Conclusions: The results of this study are indicative of “PVC-induced atriomyopathy” which responds to RFCA in short-term follow-up. Atrial dysfunction might play a role in symptoms and etiopathogenesis of LVSD.
Screening of Crude Drugs Used in Japanese Kampo Formulas for Autophagy-Mediated Cell Survival of the Human Hepatocellular Carcinoma Cell Line
Authors: Okubo Shinya , Komori Hisa , Kuwahara Asuka , Ohta Tomoe , Shoyama Yukihiro , Uto Takuhiro
Published: June 2019

Background: Autophagy is a catabolic process through which dysfunctional proteins and organelles are degraded, and that is associated with the proliferation of cancer cells. The aim of this study was to screen approximately 130 kinds of crude drugs used in Japanese Kampo formulas to identify crude drugs that would regulate the proliferation through autophagy of human hepatocellular carcinoma HepG2 cells. Methods: Extracts of each crude drug were prepared using methanol. Protein levels were determined using Western blotting. Cell viability was measured by MTT assay. Results: Among the 130 crude extracts, 24 of them increased LC3-II expression. Among these, Goboshi (burdock fruit), Soboku (sappan wood), Mokko (saussurea root), Rengyo (forsythia fruit), and Hikai (dioscorea) notably suppressed the proliferation of HepG2 cells and increased p62 expression levels, which suggested that these five extracts downregulate the autophagic activity resulting in the accumulation of p62. On the other hand, Hishinomi (water chestnut), Biwayo (loquat leaf), and Binroji (areca) induced cell growth and decreased or were uninvolved with p62 expression levels, which implied that these three extracts might induce autophagy modulators for cell growth. Conclusions: The results suggest that the compounds contained in the crude drugs selected for this study could control cell viability by regulating autophagic activity in HepG2 cells. The isolation and identification of the active compounds in these drugs might lead to the development of agents for autophagy research and cancer chemoprevention.
Influence of Excess Volumes Induced by Re and W on Dislocation Motion and Creep in Ni-Base Single Crystal Superalloys: A 3D Discrete Dislocation Dynamics Study
Authors: Gao Siwen , Yang Zerong , Grabowski Maximilian , Rogal Jutta , Drautz Ralf , Hartmaier Alexander
Published: June 2019

A comprehensive 3D discrete dislocation dynamics model for Ni-base single crystal superalloys was used to investigate the influence of excess volumes induced by solute atoms Re and W on dislocation motion and creep under different tensile loads at 850 ° C. The solute atoms were distributed homogeneously only in γ matrix channels. Their excess volumes due to the size difference from the host Ni were calculated by density functional theory. The excess volume affected dislocation glide more strongly than dislocation climb. The relative positions of dislocations and solute atoms determined the magnitude of back stresses on the dislocation motion. Without diffusion of solute atoms, it was found that W with a larger excess volume had a stronger strengthening effect than Re. With increasing concentration of solute atoms, the creep resistance increased. However, a low external stress reduced the influence of different excess volumes and different concentrations on creep.
Experimental and Numerical Analysis of Conical Projectile Impact on Inconel 718 Plates
Authors: Rodríguez-Millán Marcos , Díaz-Álvarez Antonio , Bernier Richard , Miguélez María Henar , Loya José Antonio
Published: June 2019

This paper analyses the impact behavior of Inconel 718 through experimental and numerical approach. Different conical projectiles were tested in order to obtain the ballistic curves and failure mechanisms. A three-dimensional (3D) numerical model corresponding to the experimental tests was developed using the Johnson–Cook constitutive model. The experimental data (residual velocities, global, and local perforation mechanisms) were successfully predicted with the numerical simulations. The influence of the projectile’s nose angle was found to be important when designing ballistic protections. The projectile with the narrowest angle, 40°, developed a ballistic limit approximately 10 m/s lower than the projectile with a 72° nose. The use of double-nose projectile for the same nose angle, 72°, led to a ballistic limit 12 m/s lower than that obtained for the single nose.
Estimating the Influences of Prior Residual Stress on the Creep Rupture Mechanism for P92 Steel
Authors: Liu Dezheng , Li Yan , Xie Xiangdong , Liang Guijie , Zhao Jing
Published: June 2019

Creep damage is one of the main failure mechanisms of high Cr heat-resistant steel in power plants. Due to the complex changes of stress, strain, and damage at the tip of a creep crack with time, it is difficult to accurately evaluate the effects of residual stress on the creep rupture mechanism. In this study, two levels of residual stress were introduced in P92 high Cr alloy specimens using the local out-of-plane compression approach. The specimens were then subjected to thermal exposure at the temperature of 650 °C for accelerated creep tests. The chemical composition of P92 specimens was obtained using an FLS980-stm Edinburgh fluorescence spectrometer. Then, the constitutive coupling relation between the temperature and material intrinsic flow stress was established based on the Gibbs free energy principle. The effects of prior residual stress on the creep rupture mechanism were investigated by the finite element method (FEM) and experimental method. A comparison of the experimental and simulated results demonstrates that the effect of prior residual stress on the propagation of micro-cracks and the creep rupture time is significant. In sum, the transgranular fracture and the intergranular fracture can be observed in micrographs when the value of prior residual stress exceeds and is less than the material intrinsic flow stress, respectively.
Transformation of Inclusions in Solid GCr15 Bearing Steels During Heat Treatment
Authors: Cheng Gong , Li Weifu , Zhang Xianguang , Zhang Lifeng
Published: June 2019

Laboratory heating experiments with a varied holding time of GCr15 bearing steels at 1498 K were performed to study the transformation of inclusions in solid GCr15 bearing steels during high temperature diffusion processes. Heating experiments at 1573 and 1648 K were also carried out to study the effect of these heating temperatures. Experimental results showed that inclusions transformed from Al2O3-CaO-(MgO) to Al2O3-CaS-(MgO-CaO) when the heat treatment was in the range of 1498 to 1648 K due to reactions between Al and S in the steel matrix and CaO in the inclusions. This is in good agreement with thermodynamic calculations. Moreover, the size of the inclusions hardly changed after heat treatment. The transformation rate of the inclusions depended strongly on both the heating temperature and the size of the inclusions. Kinetic analyses on the transformation of inclusions during heat treatment were performed based on a simplified analytical model. The mass transfer coefficients of CaO and CaS in inclusions were calculated, which ranged from 0.73 × 10−10 to 4.48 × 10−10 m/s.
Role of Roll Separating Force in High-Speed Twin-Roll Casting of Aluminum Alloys
Authors: Kim Min-Seok , Kim Hyoung-Wook , Kim Su-Hyeon , Kumai Shinji
Published: June 2019

The role of the roll separating force in the high-speed twin-roll casting of aluminum alloys was examined. In horizontal-type twin-roll casting, as the casting speed increased upon decreasing the roll separating force, the strip texture changed from a shear and rolling texture to a random texture. Direct temperature measurements during high-speed twin-roll casting showed that the roll separating force played a significant role in maintaining a good contact between the strip and the roll surface. This resulted in a high cooling rate around the roll nip and enabled the fabrication of a sound strip with a fine microstructure. Moreover, the high casting speed and lowered roll separating force gave a band structure consisting of fine globular grains in the mid-thickness region of the strip, which could be considered beneficial in the formation of a well-dispersed center segregation.
The Biodiversity and Geochemistry of Cryoconite Holes in Queen Maud Land, East Antarctica
Authors: Lutz Stefanie , Ziolkowski Lori A. , Benning Liane G.
Published: June 2019

Cryoconite holes are oases of microbial diversity on ice surfaces. In contrast to the Arctic, where during the summer most cryoconite holes are ‘open’, in Continental Antarctica they are most often ‘lidded’ or completely frozen year-round. Thus, they represent ideal systems for the study of microbial community assemblies as well as carbon accumulation, since individual cryoconite holes can be isolated from external inputs for years. Here, we use high-throughput sequencing of the 16S and 18S rRNA genes to describe the bacterial and eukaryotic community compositions in cryoconite holes and surrounding lake, snow, soil and rock samples in Queen Maud Land. We cross correlate our findings with a broad range of geochemical data including for the first time 13C and 14C analyses of Antarctic cryoconites. We show that the geographic location has a larger effect on the distribution of the bacterial community compared to the eukaryotic community. Cryoconite holes are distinct from the local soils in both 13C and 14C and their isotopic composition is different from similar samples from the Arctic. Carbon contents were generally low (≤0.2%) and older (6–10 ky) than the surrounding soils, suggesting that the cryoconite holes are much more isolated from the atmosphere than the soils.
Short-Term Probiotic Administration Increases Fecal-Anti Candida Activity in Healthy Subjects
Authors: De Angelis Massimiliano , Scagnolari Carolina , Oliva Alessandra , Cavallari Eugenio Nelson , Celani Luigi , Santinelli Letizia , Innocenti Giuseppe Pietro , Borrazzo Cristian , Ceccarelli Giancarlo , Vullo Vincenzo , d’Ettorre Gabriella
Published: June 2019

Background: Candida albicans’ ability to evade host immune responses represents a serious threat for vulnerable patients. Objectives: To investigate if (1) feces from healthy subjects exert anti-Candida activity; (2) fecal anti-Candida activity is modified by probiotic administration and (3) different probiotic differently modulate anti-Candida activity. Patients and methods: Feces from healthy donors were analyzed before and after seven days of dietary supplementation with two different probiotic formulations (VSL#3®; Vivomixx®). Candida albicans was cultured with decreasing concentrations of diluted feces, obtained before and after the treatment period. The relationship between anti-Candida activity of feces, interferon-α, anti-interferon-α antibodies and the expression of MxA, ISG15 and IFNAR1 was also evaluated. Results: Feces obtained prior to probiotic intake and feces collected after supplementation with VSL#3® did not affect Candida albicans growth. On the contrary, a 3log10 inhibition of Candida development was observed after Vivomixx® intake. Interferon-α played a role in the inhibition of Candida growth. Conclusion: Fecal anti-Candida activity was not observed prior to probiotic supplementation. Seven days of administration of Vivomixx® increased fecal anti-Candida activity, the same effect was not observed after intake of VSL#3®. The probiotic-induced anti-Candida activity seems to be related to an increased local production and release of interferon-α. Clinical trials are needed to determine if a short pretreatment with specific probiotic formulations may increase anti-Candida defenses in patients at risk.
Copper Mineralization Potential of Late Triassic Granitoids in Northern Yidun Arc, SW China
Authors: Li Xing-Yuan , Zhang Jing-Ru , Song Hao , Lai Chun-Kit
Published: June 2019

Yidun arc is an important constituent of the Sanjiang Tethyan Domain in SW China. The Changdagou pluton, located in the northern part of the Yidun Arc, mainly consists of granodiorite. In this study, we conducted in-situ LA-ICP-MS zircon U-Pb dating, and trace element and Hf isotope analyses on the Changdagou granites. Age dating results yielded a weighted mean U-Pb age of 214.97 ± 0.98 Ma (MSWD = 1.2, 2σ), broadly coeval with extensive late Triassic magmatism across the Yidun Arc. All zircon grains analyzed showed high concentrations of Th, U, and HREE, with positive Ce and negative Eu anomalies. Logfo2 and CeN/CeN* values vary from FMQ −3.14 to FMQ +7.44 (average FMQ +3.98), and 14 to 172 (avg. 98), respectively. The zircon EuN/EuN* (avg. 0.22) ratios have no clear correlation with the CeN/CeN* ratios, suggesting that the former were mainly affected by the magma water content. In addition, zircon εHf(t) values vary in a narrow range (–2.9 to −4.9, avg. −3.4) that clusters around zero, indicating a greater component of mantle-derived magma. Hence, we propose that the Changdagou granodiorite was derived from a highly oxidized, “wet”, Cu-rich source, of the type likely to generate porphyry Cu mineralization. However, these parameters (logfO2, EuN/EuN*, (Ce/Nd)/Y, and εHf(t)) are all lower than those of intrusions associated with Cu ores at Pulang and Lannitang, which may explain why the Cu deposit discovered at Changdagou is small by comparison. Furthermore, on the basis of the decreasing trends of εHf, logfO2, and H2O content from south to north along the Yiduan arc, we infer that the northern segment of the Yidun arc (including Changdagou) was located further away from the subduction front.
Influence of Magnesium Ions on the Preparation and Storage of DNA Tetrahedrons in Micromolar Ranges
Authors: Hu Yue , Chen Zhou , Hou Zheng , Li Mingkai , Ma Bo , Luo Xiaoxing , Xue Xiaoyan
Published: June 2019

The DNA tetrahedron (Td), as one of the novel DNA-based nanoscale biomaterials, has been extensively studied because of its excellent biocompatibility and increased possibilities for decorating precisely. Although the use of Td in laboratories is well established, knowledge surrounding the factors influencing its preparation and storage is lacking. In this research, we investigated the role of the magnesium ions, which greatly affect the structure and stability of DNA. We assembled 1, 2, 5, 10 and 20 μM Td in buffers containing different Mg2+ concentrations, demonstrating that 2 and 5 mM Mg2+ is optimal in these conditions, and that yields decrease dramatically once the DNA concentration reaches 20 μM or the Mg2+ concentration is lower than 0.5 mM. We also verified that the Td structure is retained better through freeze-thawing than lyophilization. Furthermore, a lower initial Mg2+ (≤2 mM) benefited the maintenance of Td structure in the process of lyophilization. Hence, our research sheds light on the influence of Mg2+ in the process of preparing and storing Td, and also provides some enlightenment on improving yields of other DNA nanostructures.
Novel Targeted Nano-Parthenolide Molecule against NF-kB in Acute Myeloid Leukemia
Authors: Darwish Noureldien H. E. , Sudha Thangirala , Godugu Kavitha , Bharali Dhruba J. , Elbaz Osama , El-ghaffar Hasan A. Abd , Azmy Emad , Anber Nahla , Mousa Shaker A.
Published: June 2019

The targeted nano-encapsulation of anticancer drugs can improve drug delivery and the selective targeting of cancer cells. Nuclear factor kappa B (NF-kB) is a regulator for different biological responses, including cell proliferation and differentiation. In acute myeloid leukemia (AML), constitutive NF-κB has been detected in more than 50% of cases, enabling leukemic cells to resist apoptosis and stimulate uncontrolled proliferation. We evaluated NF-kB expression in bone marrow samples from 103 patients with AML using quantitative real time polymerase chain reaction (RT-PCR) and found that expression was increased in 80.5% (83 out 103) of these patients with AML in comparison to the control group. Furthermore, overexpressed transmembrane glycoprotein (CD44) on leukemic cells in comparison to normal cells is known to play an important role in leukemic cell engraftment and survival. We designed poly lactide co-glycolide (PLGA) nanoparticles conjugated with antiCD44 and encapsulating parthenolide (PTL), a nuclear factor kappa B (NF-kB) inhibitor, in order to improve the selectivity and targeting of leukemic cells and to spare normal cells. In vitro, in leukemic cell lines Kasumi-1, KG-1a, and THP-1, proliferation was decreased by 40% (** p < 0.01) with 5 µM PLGA-antiCD44-PTL nanoparticles in comparison to the same concentration of free PTL (~10%). The higher uptake of the nanoparticles by leukemic cells was confirmed with confocal microscopy. In conclusion, PLGA-antiCD44-PTL nanoparticles improved the bioavailability and selective targeting of leukemic cells, thus holding promise as a drug delivery system to improve the cure rate of AML.
The Prevalence and Determinants of Vitamin D Status in Community-Dwelling Older Adults: Results from the English Longitudinal Study of Ageing (ELSA)
Authors: Aspell Niamh , Laird Eamon , Healy Martin , Shannon Tom , Lawlor Brian , O’Sullivan Maria
Published: June 2019

Vitamin D deficiency is often associated with adverse health outcomes in older adults. The circulating 25-hydroxyvitamin D (25(OH)D) status predominately relies on UV exposure. However, the extent of which northerly latitude exasperates deficiency is less explored in ageing. We aimed to investigate vitamin D deficiency in community-dwelling, older adults, residing at latitudes 50–55° north. This study was comprised of 6004 adults, aged >50 years from wave 6 (2012–2013) of the English Longitudinal Study of Ageing (ELSA). Deficiency was categorised by two criteria: Institute of Medicine (IOM) (<30 nmol/L) and Endocrine Society (ES) (<50 nmol/L). The overall prevalence of Institute of Medicine (IOM) and Endocrine Society (ES) definitions of deficiency were 26.4% and 58.7%, respectively. Females (odds ratio (OR) 1.23; CI: 1.04–1.44), those aged 80+ (OR: 1.42; CI: 1.01–1.93), smoking (OR: 1.88; CI: 1.51–2.34); of non-white ethnicity (OR: 3.8; CI:2.39–6.05); being obese (OR: 1.32; CI:1.09–1.58), and of poor self-reported health (OR:1.99; CI:1.33, 2.96), were more likely to be vitamin D deficient (by IOM). Residents in the south of England had a reduced risk of deficiency (OR: 0.78; CI:0.64–0.95), even after adjustment for socioeconomic and traditional predictors (obesity, age, lifestyle, etc.) of vitamin D status. Other factors, such as being retired, having a normal BMI, engaging in regular vigorous physical activity, vitamin D supplement use, sun travel, and summer season were also significantly positive correlates of deficiency. Similar results were observed for the ES cut-off definition. Importantly, more than half of adults aged >50 years had 25(OH)D concentrations <50 nmol/L. These findings demonstrate that low vitamin D status is highly prevalent in older English adults and the crucial importance of public health strategies throughout midlife and older age to achieve optimal vitamin D status.
Depression and Physical Activity Affect Diet Quality of Foreign-born Latina Women Living on the U.S.-Mexico Border
Authors: Errisuriz Vanessa L. , Delfausse Laura , Villatoro Alice P. , McDaniel Marisol D. , Esparza Laura , Parra-Medina Deborah
Published: June 2019

There is increasing evidence that depression may affect diet. However, little is known about the association between depression and diet quality among foreign-born Latinas. We hypothesized that depressive symptoms would be associated with poorer diet quality in foreign-born Latinas. Furthermore, we believed that physical activity (PA) would have a protective effect on diet quality for individuals experiencing depressive symptoms. Our study evaluated the diet (Healthy Eating Index) and PA (Actigraph GT3X activity monitors) of 534 foreign-born Latinas with and without depressive symptoms (Center for Epidemiological Studies Depression Scale). A series of logistic regression models were estimated to examine our hypotheses. As predicted, Latinas who were depressed had significantly lower odds of having a high-quality diet than non-depressed Latinas. Unexpectedly, among Latinas who met PA guidelines, depressed Latinas had a significantly lower probability of having higher-quality diets than their non-depressed counterparts. Our findings support current research stating that depressive symptoms are associated with lower Healthy Eating Index scores. More research is necessary to elucidate the relationship between PA and dietary quality of depressed Latinas. Innovative approaches to address mental health and the stressors that can compound its severity are needed to improve diet quality among foreign-born Latina women.
Chemopreventive Effects of Strawberry and Black Raspberry on Colorectal Cancer in Inflammatory Bowel Disease
Authors: Chen Tong , Shi Ni , Afzali Anita
Published: June 2019

Colorectal cancer (CRC) remains the third most common cause of cancer-related death in the United States and the fourth globally with a rising incidence. Inflammatory bowel disease (IBD) is a chronic immunologically mediated disease that imposes a significant associated health burden, including the increased risk for colonic dysplasia and CRC. Carcinogenesis has been attributed to chronic inflammation and associated with oxidative stress, genomic instability, and immune effectors as well as the cytokine dysregulation and activation of the nuclear factor kappa B (NFκB) signaling pathway. Current anti-inflammation therapies used for IBD treatment have shown limited effects on CRC chemoprevention, and their long-term toxicity has limited their clinical application. However, natural food-based prevention approaches may offer significant cancer prevention effects with very low toxicity profiles. In particular, in preclinical and clinical pilot studies, strawberry and black raspberry have been widely selected as food-based interventions because of their potent preventive activities. In this review, we summarize the roles of strawberry, black raspberry, and their polyphenol components on CRC chemoprevention in IBD.
Ethnopharmacological Properties and Medicinal Uses of Litsea cubeba
Authors: Kamle Madhu , Mahato Dipendra K. , Lee Kyung Eun , Bajpai Vivek K. , Gajurel Padam Raj , Gu Kang Sang , Kumar Pradeep
Published: June 2019

The genus Litsea is predominant in tropical and subtropical regions of India, China, Taiwan, and Japan. The plant possesses medicinal properties and has been traditionally used for curing various gastro-intestinal ailments (e.g., diarrhea, stomachache, indigestion, and gastroenteritis) along with diabetes, edema, cold, arthritis, asthma, and traumatic injury. Besides its medicinal properties, Litsea is known for its essential oil, which has protective action against several bacteria, possesses antioxidant and antiparasitic properties, exerts acute and genetic toxicity as well as cytotoxicity, and can even prevent several cancers. Here we summarize the ethnopharmacological properties, essentials oil, medicinal uses, and health benefits of an indigenous plant of northeast India, emphasizing the profound research to uplift the core and immense potential present in the conventional medicine of the country. This review is intended to provide insights into the gaps in our knowledge that need immediate focus on in-situ conservation strategies of Litsea due to its non-domesticated and dioecious nature, which may be the most viable approach and intense research for the long-term benefits of society and local peoples.
A Novel Synthetic Strategy for Preparing Polyamide 6 (PA6)-Based Polymer with Transesterification
Authors: Zhang Shengming , Zhang Jingchun , Tang Lian , Huang Jiapeng , Fang Yunhua , Ji Peng , Wang Chaosheng , Wang Huaping
Published: June 2019

In the polymerization of caprolactam, the stoichiometry of carboxyl groups and amine groups in the process of melt polycondensation needs to be balanced, which greatly limits the copolymerization modification of polyamide 6. In this paper, by combining the characteristics of the polyester polymerization process, a simple and flexible synthetic route is proposed. A polyamide 6-based polymer can be prepared by combining caprolactam hydrolysis polymerization with transesterification. First, a carboxyl-terminated polyamide 6-based prepolymer is obtained by a caprolactam hydrolysis polymerization process using a dibasic acid as a blocking agent. Subsequently, ethylene glycol is added for esterification to form a glycol-terminated polyamide 6-based prepolymer. Finally, a transesterification reaction is carried out to prepare a polyamide 6-based polymer. In this paper, a series of polyamide 6-based polymers with different molecular weight blocks were prepared by adjusting the amount and type of dibasic acid added, and the effects of different control methods on the structural properties of the final product are analyzed. The results showed that compared with the traditional polymerization method of polyamide 6, the novel synthetic strategy developed in this paper can flexibly design prepolymers with different molecular weights and end groups to meet different application requirements. In addition, the polyamide 6-based polymer maintains excellent mechanical and hygroscopic properties. Furthermore, the molecular weight increase in the polyamide 6 polymer is no longer dependent on the metering balance of the end groups, providing a new synthetic route for the copolymerization of polyamide 6 copolymer.
Sustainable Biotransformation of Oleic Acid to 10-Hydroxystearic Acid by a Recombinant Oleate Hydratase from Lactococcus garvieae
Authors: Zhang Jing , Bilal Muhammad , Liu Shuai , Zhang Jiaheng , Lu Hedong , Luo Hongzhen , Luo Chuping , Shi Hao , Iqbal Hafiz M. N. , Zhao Yuping
Published: June 2019

Enzymatic hydration of oleic acid into 10-hydroxystearic acid (10-HSA) represents a theme of substantial scientific and practical interest. In this study, a fatty acid hydratase (OHase) from Lactococcus garvieae was cloned and expressed in Escherichia coli. The recombinantly expressed enzyme was identified as oleate hydratase (EC 4.2.1.53) confirming its highest hydration activity for oleic acid. The optimally yielded enzyme fraction was purified and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). A solitary band on SDS-PAGE confirmed the molecular weight of 65 kDa. Gas chromatography-mass spectrometry (GC-MS) analysis scrutinized the silylated hydroxy fatty acid products acquired from the hydration of oleic acid by the oleate hydratase from L. garvieae. Optimal reaction conditions for the enzymatic production of 10-HSA from oleic acid using the purified oleate hydratase were pH 7.5, 30 °C, 105.49 U/mL enzyme solution and 30 g/L oleic acid. In the presence of activity stimulators, that is, magnesium (II) (Mg2+), the oleate hydratase activity was found to be greatly improved at 30 °C. In conclusion, the results revealed the potential efficacy of recombinant enzyme for the biotechnological conversion of oleic acid to 10-HSA acid with high efficiency. The results would be useful for the improved industrial-scale biosynthesis of 10-HSA via an economical and environmentally friendly bioprocess approach.
The Influence and Optimization of Geometrical Parameters on Coast-Down Characteristics of Nuclear Reactor Coolant Pumps
Authors: Zhao Yuanyuan , Si Xiangyu , Wang Xiuli , Zhu Rongsheng , Fu Qiang , Zhong Huazhou
Published: June 2019

Coast-down characteristics are the crucial safety evaluation factors of nuclear reactor coolant pumps. The energy stored at the highest moment of inertia of the reactor coolant pump unit is utilized to maintain a normal coolant supply to the core of the cooling loop system for a short period of time during the coast-down transition. As a result of the high inertia moment of the rotor system, the unit requires a high reliability of the nuclear reactor coolant pump and consumes considerable energy in the start-up and normal operation. This paper considers the operational characteristics of the coast-down transition process based on the existing hydraulic model of the nuclear reactor coolant pump. With the implementation of an orthogonal test, the hydraulic performance of the nuclear reactor coolant pump was optimized, and the optimal combination of impeller geometrical parameters was selected using multivariate linear regression to prolong the coast-down time of the reactor coolant pump and to avoid serious nuclear accidents.
Transient Modeling of Grain Structure and Macrosegregation during Direct Chill Casting of Al-Cu Alloy
Authors: Chen Qipeng , Li Hongxiang , Shen Houfa
Published: June 2019

Grain structure and macrosegregation are two important aspects to assess the quality of direct chill (DC) cast billets, and the phenomena responsible for their formation are strongly interacted. Transient modeling of grain structure and macrosegregation during DC casting is achieved with a cellular automaton (CA)–finite element (FE) model, by which the macroscopic transport is coupled with microscopic relations for grain growth. In the CAFE model, a two-dimensional (2D) axisymmetric description is used for cylindrical geometry, and a Lagrangian representation is employed for both FE and CA calculations. This model is applied to the DC casting of two industrial scale Al-6.0 wt % Cu round billets with and without grain refiner. The grain structure and macrosegregation under thermal and solutal convection are studied. It is shown that the grain structure is fully equiaxed in the grain-refined billet, while a fine columnar grain region and a coarse columnar grain region are formed in the non-grain-refined billet. With the increasing casting speed, grains become finer and grow in a direction more perpendicular to the axis, and the positive segregation near the centerline becomes more pronounced. The increasing casting temperature makes grains coarser and the negative segregation near the surface more pronounced.
Experimental Study on Spent FCC Catalysts for the Catalytic Cracking Process of Waste Tires
Authors: Wang Chuansheng , Tian Xiaolong , Zhao Baishun , Zhu Lin , Li Shaoming
Published: June 2019

Research on the synergistic high-value reuse of waste tires and used catalysts in spent fluid catalytic cracking (FCC) catalysts was carried out in this study to address the serious ecological and environmental problems caused by waste tires and spent FCC catalysts. The experiment, in which a spent FCC catalyst was applied to the catalytic cracking of waste tires, fully utilized the residual activity of the spent FCC catalyst and was compared with a waste tire pyrolysis experiment. The comparative experimental results indicated that the spent FCC catalyst could improve the cracking efficiency of waste tires, increase the output of light oil in pyrolysis products, and improve the quality of pyrolysis oil. It could also be used for the conversion of sulfur compounds during cracking. The content of 2-methyl-1-propylene in catalytic cracking gas was found to be up to 65.59%, so a new method for producing high-value chemical raw materials by the catalytic cracking of waste tires with spent FCC catalysts is proposed.
An Electrical Capacitance Array for Imaging of Water Leakage inside Insulating Slabs with Porous Cells
Authors: Li Rui , Li Yi , Peng Lihui
Published: June 2019

The paper proposes a capacitance-sensor-array-based imaging system to detect water leakage inside insulating slabs with porous cells, such as anechoic acoustic rubber tiles. The modeling is conducted by using the finite element method to obtain the electrical potential distribution and sensitivity map with the proposed capacitance sensor array. An experimental test setup, which is composed of an eight-electrode capacitance sensor array and a commercialized capacitance bridge instrument for measurement, is developed. Experiments regarding different leakage scenarios are carried out by using the test setup. Preliminary results standing for different water leakage cases, which are based on the experimental data obtained from the test setup, are presented and depicted as images reconstructed by using different algorithms including the linear back projection (LBP), the projected Landweber iteration, and the total variation regularization. These results demonstrate that the proposed capacitance sensor array is feasible and has a great potential for imaging of water leakage inside insulating slabs with porous cells. A cost-effective capacitance measurement circuit for practical applications is also proposed and simulated.