bluuebunny/crossref_metadata_2025 huggingface dataset:
Disease-Specific Comorbidity Clusters in COPD and Accelerated Aging
Authors: Triest Filip J. J. , Franssen Frits M. E. , Reynaert Niki , Gaffron Swetlana , Spruit Martijn A. , Janssen Daisy J. A. , Rutten Erica P. A. , Wouters Emiel F. M. , Vanfleteren Lowie E. G. W.
Published: April 2019

Background: Patients with chronic obstructive pulmonary disease (COPD) often suffer from multiple morbidities, which occur in clusters and are sometimes related to accelerated aging. This study aimed to assess the disease specificity of comorbidity clusters in COPD and their association with a biomarker of accelerated aging as a potential mechanistic factor. Methods: Body composition, metabolic, cardiovascular, musculoskeletal, and psychological morbidities were objectively evaluated in 208 COPD patients (age 62 ± 7 years, 58% males, FEV1 50 ± 16% predicted) and 200 non-COPD controls (age 61 ± 7 years, 45% males). Based on their presence and severity, the morbidities were clustered to generate distinct clusters in COPD and controls. Telomere length in circulating leukocytes was compared across the clusters. Results: (co)morbidities were more prevalent in COPD patients compared to controls (3.9 ± 1.7 vs. 2.4 ± 1.5, p < 0.05). A “Psychologic” and “Cachectic” cluster were only present in the COPD population. “Less (co)morbidity”, “Cardiovascular”, and “Metabolic” clusters were also observed in controls, although with less complexity. Telomere length was reduced in COPD patients, but did not differ between the (co)morbidity clusters in both populations. Conclusions: Two COPD-specific comorbidity clusters, a “Cachectic” and “Psychologic” cluster, were identified and warrant further studies regarding their development. Accelerated aging was present across various multimorbidity clusters in COPD.
Selection Criteria for Determination of Optimal Reconstruction Method for Cu-64 Trastuzumab Dosimetry on Siemens Inveon PET Scanner
Authors: Lee Seonhwa , Kim Hyeongi , Kang Ye-rin , Kim Hyungwoo , Kim Jung Young , Lee Yong-Jin , Kim Jung Min , Kim Jin Su
Published: April 2019

The goal of this study was to suggest criteria for the determination of the optimal image reconstruction algorithm for image-based dosimetry of Cu-64 trastuzumab PET in a mouse model. Image qualities, such as recovery coefficient (RC), spill-over ratio (SOR), and non-uniformity (NU), were measured according to National Electrical Manufacturers Association (NEMA) NU4-2008. Mice bearing a subcutaneous tumor ( 200   mm 3 , HER2 NCI N87) were injected with monoclonal antibodies (trastuzumab) with Cu-64. Preclinical mouse PET images were acquired at 4 time points after injection (2, 15, 40 and 64 h). Phantom and Cu-64 trastuzumab PET images were reconstructed using various reconstruction algorithms (filtered back projection (FBP), 3D reprojection algorithm (FBP-3DRP), 2D ordered subset expectation maximization (OSEM 2D), and OSEM 3D maximum a posteriori (OSEM3D-MAP)) and filters. The absorbed dose for the tumor and the effective dose for organs for Cu-64 trastuzumab PET were calculated using the OLINDA/EXM program with various reconstruction algorithms. Absorbed dose for the tumor ranged from 923 mGy/MBq to 1830 mGy/MBq with application of reconstruction algorithms and filters. When OSEM2D was used, the effective osteogenic dose increased from 0.0031 to 0.0245 with an increase in the iteration number (1 to 10). In the region of kidney, the effective dose increased from 0.1870 to 1.4100 when OSEM2D was used with iteration number 1 to 10. To determine the optimal reconstruction algorithms and filters, a correlation between RC and NU was plotted and selection criteria (0.9 < RC < 1.0 and < 10% of NU) were suggested. According to the selection criteria, OSEM2D (iteration 1) was chosen for the optimal reconstruction algorithm. OSEM2D (iteration 10) provided 154.7% overestimated effective dose and FBP with a Butterworth filter provided 20.9% underestimated effective dose. We suggested OSEM2D (iteration 1) for the calculation of the effective dose of Cu-64 trastuzumab on an Inveon PET scanner.
The Effects of the Financing Facilitation Act after the Global Financial Crisis: Has the Easing of Repayment Conditions Revived Underperforming Firms?
Authors: Yamori Nobuyoshi
Published: April 2019

After the global financial crisis, the Japanese government enacted the Financing Facilitation Act in 2009 to help small and medium-sized enterprises (SMEs) that had fallen into unprofitable conditions. Under this law, when troubled debtors asked financial institutions to ease repayment conditions (e.g., extend repayment periods or bring down interest rates), the institution would have the obligation to meet such needs as best as possible. Afterward, the changing of loan conditions began to be utilized often in Japan as a means for supporting underperforming companies. Although many countries employed various countermeasures against the global financial crisis, the Financing Facilitation Act was unique to Japan. However, there is criticism that it did not become an opportunity for companies to substantially reform their businesses, and that there was a moral hazard on the company’s side. This paper analyses whether the easing of repayment conditions revived underperforming firms and who were likely to recover, by using the “Financial Field Study After the End of the Financing Facilitation Act”, carried out by the Research Institute of Economy, Trade and Industry (RIETI) in Oct 2014. We found that the act was successful in that about 60% of companies whose loan conditions were changed recovered their performance after the loan condition changed, and the attitude that financial institutions had towards support was an important factor in whether performance recovered or not. In sum, the act might be effectual when financial institutions properly support firms, although previous studies tend to emphasize its problems.
Assessment for Sustainable Use of Quarry Fines as Pavement Construction Materials: Part I—Description of Basic Quarry Fine Properties
Authors: Zhang Yinning , Korkiala-Tanttu Leena Katariina , Gustavsson Henry , Miksic Amandine
Published: April 2019

As a secondary material, quarry fines are a valuable material to be reused for many purposes in civil engineering projects. The aggregate source depletion, especially the lack of high quality aggregates as expected in the future, as well as the demand for a carbon-neutral society and circular economy, also promotes the high-volume utilization of secondary materials such as quarry fines. The aim of this study is to do a feasibility assessment including a series of laboratory tests and analyses to evaluate the properties of quarry fine materials to determine if this type of material could be qualified as pavement construction material in high volume. The gradation information obtained from both sieving and hydrometer tests indicates the frost susceptibility of unstabilized quarry fines, therefore frost heave tests were performed and which further suggest the necessity of stabilization to improve its properties for pavement applications, especially in structural layers such as base, subbase, or filter layers. Some other general information and properties of unbound quarry fines, especially regarding their validity for application in pavement engineering are also investigated and discussed.
Effect of Solid Waste-Petroleum Coke Residue on the Hydration Reaction and Property of Concrete
Authors: Wang Liang , Quan Hongzhu , Li Qiuyi
Published: April 2019

Taking advantage of the desulfurization petroleum coke residue obtained from circulating fluidized bed boiler technology to replace a part of cement clinker and prepare the concrete can not only reduce the production of cement clinker and related CO2 emissions, but can also improve the utilization rate and utilization level of petroleum coke waste, which has good environmental and economic benefits. In this study, through the comprehensive analysis of a compressive strength test, X-ray diffraction test, and Cl− penetration resistance test, the hydration mechanism of desulfurized petroleum coke residue in concrete is revealed, and the optimum replacement ratios of single-added petroleum coke residue, multi-added petroleum coke residue, and mineral admixtures in concrete are evaluated and proposed. The results showed that mixing the 10% petroleum coke residue and 40% blast furnace slag would be most appropriate to replace the cement in concrete, thus the effective utilization of mineral admixtures and coke residue in concrete without strength loss could be realized.
Recent Advances and Perspectives of Carbon-Based Nanostructures as Anode Materials for Li-ion Batteries
Authors: Roselin L. Selva , Juang Ruey-Shin , Hsieh Chien-Te , Sagadevan Suresh , Umar Ahmad , Selvin Rosilda , Hegazy Hosameldin H.
Published: April 2019

Rechargeable batteries are attractive power storage equipment for a broad diversity of applications. Lithium-ion (Li-ion) batteries are widely used the superior rechargeable battery in portable electronics. The increasing needs in portable electronic devices require improved Li-ion batteries with excellent results over many discharge-recharge cycles. One important approach to ensure the electrodes’ integrity is by increasing the storage capacity of cathode and anode materials. This could be achieved using nanoscale-sized electrode materials. In the article, we review the recent advances and perspectives of carbon nanomaterials as anode material for Lithium-ion battery applications. The first section of the review presents the general introduction, industrial use, and working principles of Li-ion batteries. It also demonstrates the advantages and disadvantages of nanomaterials and challenges to utilize nanomaterials for Li-ion battery applications. The second section of the review describes the utilization of various carbon-based nanomaterials as anode materials for Li-ion battery applications. The last section presents the conclusion and future directions.
Enhanced High-Temperature DC Dielectric Performance of Crosslinked Polyethylene with a Polystyrene Pinning Structure
Authors: Cao Liang , Zhong Lisheng , Li Yinge , Zhang Kai , Gao Jinghui , Chen George
Published: April 2019

In this paper, we propose a method on improving direct current (DC) dielectric performance by designing a polystyrene (PS) pinning crosslinked polyethylene (XLPE) for the application of insulation materials on high voltage direct current (HVDC) extruded cable. Electrical experimental results show that the addition of PS (1–5 phr, parts per hundreds of resin) can significantly reduce DC conductivity and increase DC breakdown strength of XLPE in the test temperature range of 30–90 °C. Microstructure investigation shows PS distributed as particles could participate in the formation of a crosslinking network with the help of a crosslinking agent, thus forming a polymer pinning structure at the interface between XLPE and PS. It is believed that such a special design strengthens the structure of XLPE, which leads to the improved DC dielectric performance at elevated temperatures. Our findings may contribute a new solution for developing HVDC cable insulation materials.
Effect of Stress Wave between Adjacent Asperities Interaction on Subsurface Damage of Optical Glass in Precision Grinding
Authors: Chen Weiping , Ren Zhiying , Lin Youxi
Published: April 2019

The interaction between adjacent asperities is a typical characteristic of the grinding process and plays an important role in the material removal mechanism. Therefore, in order to systematically investigate the formation mechanism of the subsurface damage, a precision grinding contact model between the diamond particle and optical glass with adjacent asperities is proposed in our research. The initiation and propagation mechanism of median/lateral cracks under residual stress, the propagation rules of the stress waves on the subsurface, and the interaction between the subsurface damage under stress superposition effect are fully investigated by a theoretical analysis and finite element simulation. The simulation results of the precision grinding model are verified by experiments, which show that the proposed numerical analysis model is reasonable and the finite element analysis process is feasible.
Shrinkage and Durability Evaluation of Environmental Load-Reducing FRPCM by Using Silicone Oil
Authors: Choi Hyeonggil , Choi Heesup , Lee Bokyeong , Lee Dong-Eun
Published: April 2019

In this study, the shrinkage and durability of environmental load-reducing fiber-reinforced polymer cement mortar (FRPCM) were examined by using silicone oil. The results indicated that the shrinkage can be greatly reduced by adding silicone oil. However, when the silicone oil is added in excess, it affects the strength and durability. Therefore, it is possible to obtain the ECO-FRPCM which gives the effect of reducing the shrinkage and maintaining the strength and durability by adding 3% of silicone oil. From the viewpoint of shrinkage reduction, the use of silicone oil is effective as a substitute for an expansive additive or shrinkage reducing agent used in ECO-FRPCM. Also, by appropriately using silicone oil in combination with an expansive additive or a shrinkage reducing agent, shrinkage can be effectively reduced as compared with the conventional ECO-FRPCM. However, when the silicone oil and the shrinkage reducing agent are used in combination, the shrinkage cannot be efficiently reduced. It is considered that the combination of silicone oil and shrinkage reducing agent influences the mutual shrinkage reduction mechanism, but this needs to be further examined in the future.
Neural Network-Based Learning from Demonstration of an Autonomous Ground Robot
Authors: Fu Yiwei , Jha Devesh K. , Zhang Zeyu , Yuan Zhenyuan , Ray Asok
Published: April 2019

This paper presents and experimentally validates a concept of end-to-end imitation learning for autonomous systems by using a composite architecture of convolutional neural network (ConvNet) and Long Short Term Memory (LSTM) neural network. In particular, a spatio-temporal deep neural network is developed, which learns to imitate the policy used by a human supervisor to drive a car-like robot in a maze environment. The spatial and temporal components of the imitation model are learned by using deep convolutional network and recurrent neural network architectures, respectively. The imitation model learns the policy of a human supervisor as a function of laser light detection and ranging (LIDAR) data, which is then used in real time to drive a robot in an autonomous fashion in a laboratory setting. The performance of the proposed model for imitation learning is compared with that of several other state-of-the-art methods, reported in the machine learning literature, for spatial and temporal modeling. The learned policy is implemented on a robot using a Nvidia Jetson TX2 board which, in turn, is validated on test tracks. The proposed spatio-temporal model outperforms several other off-the-shelf machine learning techniques to learn the policy.
Best Proximity Point Theorems for Two Weak Cyclic Contractions on Metric-Like Spaces
Authors: Karapınar Erdal , Chen Chi-Ming , Lee Chih-Te
Published: April 2019

In this paper, we establish two best proximity point theorems in the setting of metric-like spaces that are based on cyclic contraction: Meir–Keeler–Kannan type cyclic contractions and a generalized Ćirić type cyclic φ -contraction via the MT -function. We express some examples to indicate the validity of the presented results. Our results unify and generalize a number of best proximity point results on the topic in the corresponding recent literature.
A Population-Based Study of Secondary Prostate Cancer Risk after Radiotherapy in Male Patients with Rectal Cancer: A Retrospective Cohort Study
Authors: Chuang Jen-Pin , Lee Yen-Chien , Lee Jenq-Chang , Lu Chin-Li , Li Chung-Yi
Published: April 2019

Background and objective: Risk of secondary prostate cancer after radiation therapy among patients with rectal cancer remains undetermined. Given an increased incidence of rectal cancer in younger people and improved survival for rectal cancer patients who received radiation therapy, the potential risk of secondary prostate cancer needs to be further investigated. Materials and Methods: Male patients (n = 11,367) newly diagnosed rectal cancer and who underwent abdominoperineal resection (APR) or low anterior resection (LAR) from 1 January, 1998 to 31 December, 2010 were identified from Taiwan National Health Insurance Research Database. The incidence and relative risk of secondary prostate cancer in study patients with (n = 1586) and without (n = 9781) radiotherapy within one year after rectal cancer diagnosis were compared using a competing-risks analysis. Results: Rectal cancer patients with radiotherapy were at a significantly decreased risk of developing prostate cancer, with a hazard ratio (HR) of 0.41 (95% confidence interval = 0.20–0.83) after adjustment for age. Analysis of the risk estimated for various follow-up lengths suggested that a decreasing HR was seen through the period followed-up and that there was a trend of decreasing prostate cancer risk with time after radiotherapy. Conclusions: Radiotherapy was significantly associated with decreased risk of secondary prostate cancer among rectal cancer patients, by a magnitude of 59%.
The Effects of Acute and Chronic Aerobic Activity on the Signaling Pathway of the Inflammasome NLRP3 Complex in Young Men
Authors: Khakroo Abkenar Iman , Rahmani-nia Farhad , Lombardi Giovanni
Published: April 2019

Background and Objectives: The results of the studies show that the intensity and volume of aerobic exercise activity produce different responses of the immune system. This study aims to show how the signaling pathway of the inflammatory NLRP3 complex is influenced by the acute and chronic effects of moderate and high-intensity aerobic exercises in young men. Materials and Methods: Accordingly, 60 healthy (BMI = 23.56 ± 2.67) young (24.4 ± 0.4) students volunteered to participate in the study that was randomly divided into two experimental (n = 20) groups and one control (n = 20) group. The training protocol started with two intensity levels of 50% for a moderate group and 70% of maximum heart rate for high group for 30 min and then continued until reaching 70% (moderate group) and 90% (high group) of the maximum heart rate, respectively. Using Real Time-PCR method, the expression of NLRP3 gene and ELISA- were measured by IL-1β, IL-18. Results: The results showed that acute aerobic exercise with moderate intensity had no significant effect on the expression of NLRP3 gene and serum levels of IL-1β and IL-18 cytokines (p > 0.05) when acute exercise, with high intensity, begins an initiation of the activity of the inflammatory complex with elevated serum levels of IL-1β, IL-18, and NLRP3 gene expression (p < 0.05). In addition, chronic exercise with moderate intensity significantly reduced the expression of NLRP3 gene and serum levels of IL-1β, IL-18 cytokines (p < 0.05). In the case of chronic exercise with high intensity, a significant increase in expression of gene, NLRP3 and serum levels of IL-1β, IL-18 cytokines were observed (p < 0.05). Conclusions: Generally, it can be concluded that chronic exercise with moderate intensity is effective in decreasing the expression of the inflammasome and inflammation.
Efficacy of Antiseptic Solutions in Treatment of Staphylococcus Aureus Infected Surgical Wounds with Patches of Vascular Graft: An Experimental Study in Rats
Authors: Stanevičiūtė Elvyra , Builytė Inga Urtė , Ridziauskas Martynas , Besusparis Justinas , Kirkliauskienė Agnė , Zabulis Vaidotas , Davainis Linas , Valiūnaitė Gabrielė , Triponis Vytautas , Sirvydis Vytautas
Published: April 2019

Background and objectives: Treatment of a prosthetic vascular graft infection (PVGI) remains a challenging problem in vascular surgery. The aim of this study was to design a novel rat model for treatment of peripheral vascular prosthesis infection caused by Staphylococcus aureus (S. aureus) and to determine the efficacy of different antiseptic solutions in suppressing or eradicating infection from the wound and the graft material itself. Materials and methods: A piece of Dacron vascular prosthesis was surgically implanted at the dorsum of 48 Wistar rats and the wounds were infected with 5 McFarland standard inoculum of S. aureus. Suppurating wounds were daily irrigated with different antiseptic solutions: octenidine dihydrochloride, povidone-iodine, chlorhexidine digluconate, and sterile saline. The antimicrobial action of antiseptics was defined according to their capability to eradicate bacteria from the graft surroundings and bacteriological examination of the graft itself. Extended studies on wound microbiology, cytology, and histopathology were performed with an additional group of 10 rats, treated with the most effective antiseptic-octenidine dihydrochloride. Results: Four-day treatment course with octenidine, povidone-iodine, and chlorhexidine resulted in 99.98% (p = 0.0005), 90.73% (p = 0.002), and 65.97% (p = 0.004) decrease in S. aureus colonies in wound washouts, respectively. The number of S. aureus colonies increased insignificantly by 19.72% (p = 0.765) in control group. Seven-day treatment course with octenidine eradicated viable bacteria from nine out of 10 wound washouts and sterilized one vascular graft. Conclusions: A reproducible rat model of PVGI with a thriving S. aureus infection was designed. It is a first PVGI animal model where different antiseptic solutions were applied as daily irrigations to treat peripheral PVGI. Seven-day treatment with octenidine eradicated bacteria from the wound washouts for 90% of rats and one vascular graft. Further studies are needed to investigate if irrigations with octenidine could properly cure vascular bed from infection to assure a successful implantation of a new synthetic vascular substitute.
Study of the Deposition Formation Mechanism in the Heat Exchanger System of RHF
Authors: Pan Yuzhu , She Xuefeng , Wang Jingsong , Liu Yingli
Published: April 2019

In rotary hearth furnace (RHF) production, the heat transfer system will produce deposition, which blocks the exhaust channel. The formation of deposition will affect RHF production. In this study, the formation mechanism of deposition was determined through chemical composition analysis, XRD and SEM-EDS: the main cohered phase in the deposition was KCl and the secondary cohered phase was ZnFe2O4; the ZnFe2O4 had become solid since it was formed with a porous structure and it cohered other substances; the ZnFe2O4 exhibited stronger cohering strength than KCl, due to a different cohering mechanism. In contrast, the KCl played a significant role in the deposition on the heat exchanger wall. A new process was proposed to avoid the deposition formation. This process could eliminate the deposition in the heat transfer system of RHF and improve the utilization of metallurgical waste.
Plasma Free Fatty Acids Metabolic Profile with LC-MS and Appetite-Related Hormones in South Asian and White European Men in Relation to Adiposity, Physical Activity and Cardiorespiratory Fitness: A Cross-Sectional Study
Authors: Benedetti Simone , Al-Tannak Naser F. , Alzharani Mansour , Moir Hannah J. , Stensel David J. , Thackray Alice E. , Naughton Declan P. , Dorak Mehmet T. , Spendiff Owen , Hill Natasha , Watson David G. , Allgrove Judith
Published: April 2019

South Asians have a greater cardiovascular disease (CVD) and type 2 diabetes (T2D) risk than white Europeans, but the mechanisms are poorly understood. This study examined ethnic differences in free fatty acids (FFAs) metabolic profile (assessed using liquid chromatography-mass spectrometry), appetite-related hormones and traditional CVD and T2D risk markers in blood samples collected from 16 South Asian and 16 white European men and explored associations with body composition, objectively-measured physical activity and cardiorespiratory fitness. South Asians exhibited higher concentrations of five FFAs (laurate, myristate, palmitate, linolenic, linoleate; p ≤ 0.040), lower acylated ghrelin (ES = 1.00, p = 0.008) and higher leptin (ES = 1.11, p = 0.004) than white Europeans; total peptide YY was similar between groups (p = 0.381). South Asians exhibited elevated fasting insulin, C-reactive protein, interleukin-6, triacylglycerol and ratio of total cholesterol to high-density lipoprotein cholesterol (HDL-C) and lower fasting HDL-C (all ES ≥ 0.74, p ≤ 0.053). Controlling for body fat percentage (assessed using air displacement plethysmography) attenuated these differences. Despite similar habitual moderate-to-vigorous physical activity (ES = 0.18, p = 0.675), V ˙ O2max was lower in South Asians (ES = 1.36, p = 0.001). Circulating FFAs in South Asians were positively correlated with body fat percentage (r2 = 0.92), body mass (r2 = 0.86) and AUC glucose (r2 = 0.89) whereas in white Europeans FFAs were negatively correlated with total step counts (r2 = 0.96). In conclusion, South Asians exhibited a different FFA profile, lower ghrelin, higher leptin, impaired CVD and T2D risk markers and lower cardiorespiratory fitness than white Europeans.
Multichannel Inductive Sensor Based on Phase Division Multiplexing for Wear Debris Detection
Authors: Wu Sen , Liu Zhijian , Yuan Haichao , Yu Kezhen , Gao Yuefeng , Liu Liankun , Pan Xinxiang
Published: April 2019

Inductive wear debris sensor has been widely used in real time machine lubricant oil condition monitoring and fault forecasting. However, the small sensing zone, which is designed for high sensitivity, of the existing sensors leads to low throughput. In order to improve the throughput, a novel multichannel wear debris sensor that is based on phase division multiplexing is presented. By introducing the phase shift circuit into the system, multiple sensing coils could work at different initial phases. Multiple signals of sensing coils could be combined into one output without information loss. Synchronized sampling is used for data recording, and output signals of multiple sensing coils are extracted from the recorded data. A four-channel wear debris sensor system was designed to demonstrate our method. Subsequently, crosstalk analysis, pseudo-dynamic testing and dynamic testing were conducted to check the sensing system. Results show that signals of four sensing coils could be simultaneously detected and the detection limit for ferrous wear debris is 33 μm. Using the presented method, real time wear debris detection in multiple channels could be achieved without increasing the number of excitation source and data acquisition equipment.
Formation Conditions and 40Ar/39Ar Age of the Gem-Bearing Boqueirão Granitic Pegmatite, Parelhas, Rio Grande do Norte, Brazil
Authors: Strmić Palinkaš Sabina , Palinkaš Ladislav , Neubauer Franz , Scholz Ricardo , Borojević Šoštarić Sibila , Bermanec Vladimir
Published: April 2019

The Boqueirão granitic pegmatite, alias Alto da Cabeça pegmatite, is situated in Borborema Pegmatitic Province (BPP) in Northeast Brazil. This pegmatitic province hosts globally important reserves of tantalum and beryllium, as well as significant quantities of gemstones, including aquamarine, morganite, and the high-quality turquoise-blue “Paraíba Elbaite”. The studied lithium-cesium-tantalum Boqueirão granitic pegmatite intruded meta-conglomerates of the Equador Formation during the late Cambrian (502.1 ± 5.8 Ma; 40Ar/39Ar plateau age of muscovite). The pegmatite exhibits a typical zonal mineral pattern with four defined zones (Zone I: muscovite, tourmaline, albite, and quartz; Zone II: K-feldspar (microcline), quartz, and albite; Zone III: perthite crystals (blocky feldspar zone); Zone IV: massive quartz). Huge individual beryl, spodumene, tantalite, and cassiterite crystals are common as well. Microscopic examinations revealed that melt inclusions were entrapped simultaneously with fluid inclusions, suggesting the magmatic–hydrothermal transition. The magmatic–hydrothermal transition affected the evolution of the pegmatite, segregating volatile compounds (H2O, CO2, N2) and elements that preferentially partition into a fluid phase from the viscous silicate melt. Fluid inclusion studies on microcline and associated quartz combined with microthermometry and Raman spectroscopy gave an insight into the P-T-X characteristics of entrapped fluids. The presence of spodumene without other LiAl(SiO3)2 polymorphs and constructed fluid inclusion isochores limited the magmatic–hydrothermal transition at the gem-bearing Boqueirão granitic pegmatite to the temperature range between 300 and 415 °C at a pressure from 1.8 to 3 kbar.
Ni/Co-Catalyzed Homo-Coupling of Alkyl Tosylates
Authors: Komeyama Kimihiro , Tsunemitsu Ryusuke , Michiyuki Takuya , Yoshida Hiroto , Osaka Itaru
Published: April 2019

A direct reductive homo-coupling of alkyl tosylates has been developed by employing a combination of nickel and nucleophilic cobalt catalysts. A single-electron-transfer-type oxidative addition is a pivotal process in the well-established nickel-catalyzed coupling of alkyl halides. However, the method cannot be applied to the homo-coupling of ubiquitous alkyl tosylates due to the high-lying σ*(C–O) orbital of the tosylates. This paper describes a Ni/Co-catalyzed protocol for the activation of alkyl tosylates on the construction of alkyl dimers under mild conditions.
Synergistic Effect of Low Molecular Weight Polyethylenimine and Polyethylene Glycol Components in Dynamic Nonviral Vector Structure, Toxicity, and Transfection Efficiency
Authors: Craciun Bogdan Florin , Gavril Gabriela , Peptanariu Dragos , Ursu Laura Elena , Clima Lilia , Pinteala Mariana
Published: April 2019

When studying polyethylenimine derivatives as nonviral vectors for gene delivery, among the important issues to be addressed are high toxicity, low transfection efficiency, and nucleic acid polyplex condensation. The molecular weight of polyethylenimine, PEGylation, biocompatibility and, also, supramolecular structure of potential carrier can all influence the nucleic acid condensation behavior, polyplex size, and transfection efficiency. The main challenge in building an efficient carrier is to find a correlation between the constituent components, as well as the synergy between them, to transport and to release, in a specific manner, different molecules of interest. In the present study, we investigated the synergy between components in dynamic combinatorial frameworks formed by connecting PEGylated squalene, poly-(ethyleneglycol)-bis(3-aminopropyl) and low molecular weight polyethylenimine components to 1,3,5-benzenetrialdehyde, via reversible imine bond, applying a dynamic combinatorial chemistry approach. We report comparative structural and morphological data, DNA binding affinity, toxicity and transfection efficiency concerning the ratio of polyethylenimine and presence or absence of poly-(ethyleneglycol)-bis(3-aminopropyl) in composition of dynamic combinatorial frameworks. In vitro biological assessments have revealed the fact that nonviral vectors containing poly-(ethyleneglycol)-bis(3-aminopropyl) and the lowest amount of polyethylenimine have significant transfection efficiency at N/P 50 ratio and display insignificant cytotoxicity on the HeLa cell line.
Microencapsulation of Elsholtzia ciliata Herb Ethanolic Extract by Spray-Drying: Impact of Resistant-Maltodextrin Complemented with Sodium Caseinate, Skim Milk, and Beta-Cyclodextrin on the Quality of Spray-Dried Powders
Authors: Pudziuvelyte Lauryna , Marksa Mindaugas , Jakstas Valdas , Ivanauskas Liudas , Kopustinskiene Dalia M. , Bernatoniene Jurga
Published: April 2019

Spray-drying is the most popular encapsulation method used for the stabilization and protection of biologically active compounds from various environmental conditions, such as oxidation, moisture, pH, and temperature. Spray-drying increases the bioavailability of the natural active compounds and improves the solubility of low-soluble compounds. The aim of this work was to study the effects of different wall materials and optimize wall material solution’s composition on physicochemical properties of microcapsules loaded with phenolics, extract rich in volatile compounds and essential oil from Elsholtzia ciliata herb. For encapsulation of elsholtzia and dehydroelsholtzia ketones, more suitable wall materials were used—beta-cyclodextrin and sodium caseinate. Four phenolics—sodium caseinate, skim milk, beta-cyclodextrin, and resistant-maltodextrin—were used. A D-optimal mixture composition design was used to evaluate the effect of wall material solution’s composition using sodium caseinate (0.5–1 g), skim milk (6–10 g), resistant-maltodextrin (8–12 g), and beta-cyclodextrin (0.5–1 g) for the encapsulation efficiency, drying yield, and physicochemical properties. The optimal mixture composition was 0.54 g of sodium caseinate, 10 g of skim milk, 8.96 g of resistant-maltodextrin, and 0.5 g of beta-cyclodextrin. These encapsulating agents had a good performance in the microencapsulation of E. ciliata ethanolic extracts by the spray-drying technique. It is proven that the produced microparticles have a good potential to be included in various pharmaceutical forms or food supplements.
Structure–Activity Relationships of the Tetrapeptide Ac-His-Arg-(pI)DPhe-Tic-NH2 at the Mouse Melanocortin Receptors: Modification at the (pI)DPhe Position Leads to mMC3R Versus mMC4R Selective Ligands
Authors: Schlasner Katherine N. , Ericson Mark D. , Doering Skye R. , Freeman Katie T. , Weinrich Mary , Haskell-Luevano Carrie
Published: April 2019

The five melanocortin receptors (MC1R–MC5R) are involved in numerous biological pathways, including steroidogenesis, pigmentation, and food intake. In particular, MC3R and MC4R knockout mice suggest that the MC3R and MC4R regulate energy homeostasis in a non-redundant manner. While MC4R-selective agonists have been utilized as appetite modulating agents, the lack of MC3R-selective agonists has impeded progress in modulating this receptor in vivo. In this study, the (pI)DPhe position of the tetrapeptide Ac-His-Arg-(pI)DPhe-Tic-NH2 (an MC3R agonist/MC4R antagonist ligand) was investigated with a library of 12 compounds. The compounds in this library were found to have higher agonist efficacy and potency at the mouse (m) MC3R compared to the MC4R, indicating that the Arg-DPhe motif preferentially activates the mMC3R over the mMC4R. This observation may be used in the design of new MC3R-selective ligands, leading to novel probe and therapeutic lead compounds that will be useful for treating metabolic disorders.
Comparison of Two Process Schemes Combining Hydrothermal Treatment and Acidogenic Fermentation of Source-Separated Organics
Authors: Lin Long , Hosseini Koupaie Ehssan , Azizi Armineh , Bazyar Lakeh Amir Abbas , Dhar Bipro R. , Hafez Hisham , Elbeshbishy Elsayed
Published: April 2019

This study compares the effects of pre- and post-hydrothermal treatment of source- separated organics (SSO) on solubilization of particulate organics and acidogenic fermentation for volatile fatty acids (VFAs) production. The overall COD solubilization and solids removal efficiencies from both schemes were comparable. However, the pre-hydrolysis of SSO followed by acidogenic fermentation resulted in a relatively higher VFA yield of 433 mg/g VSS, which was 18% higher than that of a process scheme with a post-hydrolysis of dewatered solids from the fermentation process. Regarding the composition of VFA, the dominance of acetate and butyrate was comparable in both process schemes, while propionate concentration considerably increased in the process with pre-hydrolysis of SSO. The microbial community results showed that the relative abundance of Firmicutes increased substantially in the fermentation of pretreated SSO, indicating that there might be different metabolic pathways for production of VFAs in fermentation process operated with pre-treated SSO. The possible reason might be that the abundance of soluble organic matters due to pre-hydrolysis might stimulate the growth of more kinetically efficient fermentative bacteria as indicated by the increase in Firmicutes percentage.
Propylene Polymerization Catalyzed by Metallocene/Methylaluminoxane Systems on Rice Husk Ash
Authors: Li Kuo-Tseng , Yang Cheng-Ni
Published: April 2019

Silica generated from agricultural waste is more cost effective and environmentally friendly than silica from traditional commercial processes. In this study, spherical silica particles with a diameter of around 120 nm were fabricated from rice husk ash (RHA), and were used to support two bridged zirconcene complexes ((I) Me2Si(Ind)2ZrCl2 and (II) C2H4(Ind)2ZrCl2) for catalyzing propylene polymerization to produce polypropylene (PP) in a temperature range of 40–70 °C and in a solution methylaluminoxane (MAO) range of 0.1–0.6 wt%. Due to its small particle size, RHA-supported catalyst exhibited much higher activity than micro-sized commercial silica-supported catalyst. At the optimum polymerization temperature of 55 °C and with increasing MAO concentration, polymer yield increased proportionally with the increase of number average molecular weight. Compared to (I), (II) produced more polymer molecules but with much shorter chain length, ascribed to the differences of Zr loading and bridge structure. With increasing polymerization temperature, polymer molecular weight decreased rapidly and resulted in a significant change of PP assembly morphology (shape and size). At 55 °C, (I) produced uniform PP assemblies which had dumbbell-like structure with a smooth middle section and two fibrillar ends, while (II) produced spherical PP particles. The dumbbell middle part width was essentially identical to the Batchelor microscale proposed in turbulent mixing theory.
Inhibition of Human Platelet Aggregation and Low-Density Lipoprotein Oxidation by Premna foetida Extract and Its Major Compounds
Authors: Dianita Roza , Jantan Ibrahim
Published: April 2019

Many Premna species have been used in traditional medicine to treat hypertension and cardiac insufficiency, and as a tonic for cardiac-related problems. Some have been reported to possess cardiovascular protective activity through several possible mechanisms, but not Premna foetida. In the present study, the methanol extract of P. foetida leaves (PFM) and its isolated compounds were evaluated for their ability to inhibit copper-mediated human low-density lipoprotein (LDL) oxidation and arachidonic acid (AA)- and adenosine diphosphate (ADP)-induced platelet aggregation. Six flavonoids, three triterpenoids, vanillic acid and stigmasterol were successfully isolated from PFM. Of the isolated compounds, quercetin was the most active against LDL oxidation (IC50 4.25 µM). The flavonols were more active than the flavones against LDL oxidation, suggesting that hydroxyl group at C-3 and the catechol moiety at B-ring may play important roles in protecting LDL from oxidation. Most tested flavonoids showed stronger inhibition towards AA-induced than the ADP-induced platelet aggregation with apigenin exhibiting the strongest effect (IC50 52.3 and 127.4 µM, respectively) while quercetin and kaempferol showed moderate activity. The results suggested that flavonoids, especially quercetin, apigenin and kaempferol were among the major constituents of P. foetida responsible for anti-LDL oxidation and anti-platelet aggregation.
A Modified QuEChERS Method for Determination of Pyrethroid Residues in Traditional Chinese Medicine Oral Liquids by High-Performance Liquid Chromatography
Authors: Hou Yuge , Chen Hong , Li Xin , Liao Yiyi , Tsunoda Makoto , Zhang Yingxia , Deng Shiming , Song Yanting
Published: April 2019

Pyrethroid residues in traditional Chinese medicines have been a serious threat to the health and treatment of patients. However, because of the matrix complexity of traditional Chinese medicine, the detection of pyrethroid residues remains a challenge. Therefore, we developed a QuEChERS method coupled with high-performance liquid chromatography and ultraviolet detection (HPLC-UV) for the determination of pyrethroid pesticides in three kinds of traditional Chinese medicine oral liquid preparations, and we investigated and optimized the extraction conditions. The matrix effect was estimated in the organic solvent and the actual samples by comparing the slopes of calibration curves, and the results showed that the matrix effect is not significant when using the modified QuEChERS method. The pyrethroid pesticides could be completely separated in 30 min. The linear correlation coefficients were more than 0.999, and the recoveries of all the pyrethroid pesticides ranged from 87.2% to 104.8%. The intra-day precisions (n = 5) were 2.44–4.62%, and the inter-day precisions (n = 5) were 1.06–3.02%. Moreover, the limits of detection were in the range of 0.007–0.018 ng mL−1, while the limits of quantitation were in the range of 0.022–0.057 ng mL−1. This simple, low-cost, and highly sensitive analytical method can be a potential tool for the analysis of pyrethroid residues in traditional Chinese medicine oral liquid preparations.
Asymmetric Henry Reaction of 2-Acylpyridine N-Oxides Catalyzed by a Ni-Aminophenol Sulfonamide Complex: An Unexpected Mononuclear Catalyst
Authors: Liu Mouxiong , Gui Dongdong , Deng Ping , Zhou Hui
Published: April 2019

The asymmetric Henry reaction of 2-acylpyridine N-oxide remains a challenge as N-oxides generally act as competitive catalyst inhibitors or displace activating ligands. A novel variable yield (up to 99%) asymmetric Henry reaction of 2-acypyridine N-oxides catalyzed by a Ni-aminophenol sulfonamide complex with good to excellent enantioselectivity (up to 99%) has been developed. Mechanistic studies suggest that the unique properties of the electron-pairs of N-oxides for complexation with Ni makes the unexpected mononuclear complex, rather than the previously reported dinuclear complex, the active species.
Importance of Chiral Recognition in Designing Metal-Free Ligands for G-Quadruplex DNA
Authors: Răsădean Dora M. , Harrison Samuel W. O. , Owens Isobel R. , Miramont Aucéanne , Bromley Frances M. , Pantoș G. Dan
Published: April 2019

Four pairs of amino acid-functionalized naphthalenediimide enantiomers (d- and l-lysine derived NDIs) were screened toward G-quadruplex forming sequences in telomeres (h-TELO) and oncogene promoters: c-KIT1, c-KIT2, k-RAS and BCL-2. This is the first study to address the effect of point chirality toward G-quadruplex DNA stabilization using purely small organic molecules. Enantioselective behavior toward the majority of ligands was observed, particularly in the case of parallel conformations of c-KIT2 and k-RAS. Additionally, Nε-Boc-l-Lys-NDI and Nε-Boc-d-Lys-NDI discriminate between quadruplexes with parallel and hybrid topologies, which has not previously been observed with enantiomeric ligands.
Anti-Mycobacterium tuberculosis Terpenoids from Resina Commiphora
Authors: Zhu Chuan-Zhi , Hu Bin-Yuan , Liu Jia-Wang , Cai Yi , Chen Xin-Chun , Qin Da-Peng , Cheng Yong-Xian , Zhang Zong-De
Published: April 2019

Four new compounds including two new sesquiterpenoid dimers, commiphoroids E (1) and F (2), a new triterpenoid (3), and a new sesquiterpenoid (4), along with three known terpenoids (5−7) were isolated from Resina Commiphora, whose structures were identified by NMR spectra, HRESIMS, and X-ray diffraction analysis. Compounds 1 and 2 both bear an O-bridge ring and feature a plausible [4 + 2] Diels–Alder cycloaddition reaction. Antimycobacterial activities show that all the tested compounds (200 μM) could inhibit the growth of both sensitive and clinically multi-drug resistant (MDR) isolated strains. In addition, cellular toxicity of the isolates against human cancer cells and THP-1 monocyte cells was examined.
Characterization of Tapeworm Metabolites and Their Reported Biological Activities
Authors: Wangchuk Phurpa , Constantinoiu Constantin , Eichenberger Ramon M. , Field Matt , Loukas Alex
Published: April 2019

Parasitic helminths infect billions of people, livestock, and companion animals worldwide. Recently, they have been explored as a novel therapeutic modality to treat autoimmune diseases due to their potent immunoregulatory properties. While feeding in the gut/organs/tissues, the parasitic helminths actively release excretory-secretory products (ESP) to modify their environment and promote their survival. The ESP proteins of helminths have been widely studied. However, there are only limited studies characterizing the non-protein small molecule (SM) components of helminth ESP. In this study, using GC-MS and LC-MS, we have investigated the SM ESP of tapeworm Dipylidium caninum (isolated from dogs) which accidentally infects humans via ingestion of infected cat and dog fleas that harbor the larval stage of the parasite. From this D. caninum ESP, we have identified a total of 49 SM (35 polar metabolites and 14 fatty acids) belonging to 12 different chemotaxonomic groups including amino acids, amino sugars, amino acid lactams, organic acids, sugars, sugar alcohols, sugar phosphates, glycerophosphates, phosphate esters, disaccharides, fatty acids, and fatty acid derivatives. Succinic acid was the major small molecule present in the D. caninum ESP. Based on the literature and databases searches, we found that of 49 metabolites identified, only 12 possessed known bioactivities.
Self-Assembly Properties of Cationic Gemini Surfactants with Biodegradable Groups in the Spacer
Authors: Pisárčik Martin , Polakovičová Mája , Markuliak Mário , Lukáč Miloš , Devínsky Ferdinand
Published: April 2019

: Self-assembly properties of cationic gemini surfactants with biodegradable amide or ester groups in the spacer were investigated utilising time-resolved fluorescence quenching, dynamic light scattering and zeta potential measurements. A correlation between aggregation parameters such as micelle aggregation number, micelle size and zeta potential with the structure of gemini molecules was made. For gemini molecules with medium spacer lengths, micelle aggregation number does not change much with the surfactant concentration. When the spacer is extended, a stronger aggregation tendency is observed for gemini surfactant molecules with two ester groups in the spacer and the aggregation number increases. The assumption of stronger aggregation of ester-based gemini molecules at larger spacer number values is also documented by measurements of the size and zeta potential of ester-based micelles. The explanation of the difference in aggregation ability of amide-based and ester-based gemini molecules is related to the structural features of gemini molecules, notably to the larger flexibility and denser arrangement of ester-based gemini molecules in a micelle. To support this assumption, optimised 3D models of the studied gemini molecules were constructed. Correspondingly, the calculations show smaller size and interfacial area for ester-based gemini conformers.
Avoiding the Interference of Doxorubicin with MTT Measurements on the MCF-7 Breast Cancer Cell Line
Authors: Luis Carla , Castaño-Guerrero Yuselis , Soares Raquel , Sales Goreti , Fernandes Rúben
Published: April 2019

Doxorubicin (DOXO) is an adjuvant chemotherapy agent and is also commonly used in cell biology research. Cytotoxic assays in cell culture are frequently used in order to stablish drug concentrations that are useful for controlling cell proliferation. One common cytotoxic method used is 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT). Our present research aims to support future studies in engaging MTT assay using DOXO that exhibits a strong red coloration and fluorescence, and so it is assumed that DOXO may interfere with commonly used colorimetric assays such as MTT. The interference of DOXO in the MTT determination was evaluated in a Breast Cancer cell line Michigan Cancer Foundation-7 (MCF-7). The interference was evaluated by means of spectroscopic methods in particular spectrophometry and fluorescence spectroscopy of MTT and DOXO. We postulate that the medium and the MTT reagent itself can interfere on the metabolic activity method, so in order to achieve better results, DMEM was replaced by a neutral buffer like Phosphate-buffered saline (PBS). This protocol may be extremely useful in future studies involving DOXO.