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Open AccessArticle
Structural Characterization of Lignin in Fruits and Stalks of Chinese Quince
Molecules 2017, 22(6), 890; doi:10.3390/molecules22060890 (registering DOI) -
Abstract
Chinese quince (Chaenomeles sinensis) is used in food and pharmaceutical products, but it is seldom eaten as a raw fruit due to its astringent, woody flesh. The structural characterization of lignin fractions from Chinese quince was very important to investigate the
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Chinese quince (Chaenomeles sinensis) is used in food and pharmaceutical products, but it is seldom eaten as a raw fruit due to its astringent, woody flesh. The structural characterization of lignin fractions from Chinese quince was very important to investigate the structure-activity relationships of lignin. In this investigation, to characterize the structure of lignin in Chinese quince fruits, the milled wood lignin sample was isolated from the fruits (FMWL) and the chemical structure of FMWL was investigated by sugar analysis, FT-IR, GPC, pyrolysis-GC/MS analysis, UV spectra analysis, thermogravimetric analysis (TGA), and advanced NMR spectroscopic techniques. In addition, the lignin fraction from the stalk of Chinese quince (SMWL) was also prepared for comparison to obtained more information of lignin structure in the fruits. The results showed that the two lignin fractions isolated from fruit and stalk of Chinese quince exhibited different structural features. The two MWL samples were mainly composed of β-O-4 ether bonds, β-5 and β-β′ carbon-carbon linkages in the lignin structural units. Compared to the SMWL, the FMWL fraction had the higher S/G ratio and more carbohydrates linkages. The predominant carbohydrates associated with FMWL and SMWL fractions were glucans-type hemicelluloses and xylan-type hemicelluloses, respectively. Understanding the structure of lignin could give insight into the properties of the lignin and enable the food processing industry to separate lignin more efficiently. Full article
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Open AccessArticle
Quantifying the National Significance of Local Areas for Regional Conservation Planning: North Carolina’s Mountain Treasures
Land 2017, 6(2), 35; doi:10.3390/land6020035 (registering DOI) -
Abstract
Conservation scientists recognize that additional protected areas are needed to maintain biological diversity and ecological processes. As regional conservation planners embark on recommending additional areas for protection in formal ecological reserves, it is important to evaluate candidate lands for their role in building
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Conservation scientists recognize that additional protected areas are needed to maintain biological diversity and ecological processes. As regional conservation planners embark on recommending additional areas for protection in formal ecological reserves, it is important to evaluate candidate lands for their role in building a resilient protected areas system of the future. Here, we evaluate North Carolina’s Mountain Treasures with respect to their (1) ecological integrity, (2) role in connecting existing core protected areas, (3) potential to diversify the ecosystem representation of reserves, and (4) role in maintaining hotspots of biologically-rich areas that are not well protected. Mountain Treasures represent a citizen inventory of roadless areas and serve as candidates for elevated levels of conservation protection on U.S. federal lands. We compared Mountain Treasures to other candidate lands throughout the country to evaluate their potential national significance. While the Mountain Treasures tended to be more impacted by human modifications than other roadless areas, they are as important as other roadless areas with respect to their role in connecting existing protected areas and diversifying representation of ecosystems in conservation reserves. However, Mountain Treasures tended to have a much higher biodiversity priority index than other roadless areas leading to an overall higher composite score compared to other roadless areas. Our analysis serves as an example of how using broad-scale datasets can help conservation planners assess the national significance of local areas. Full article
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Open AccessArticle
Islam and Democracy: Conflicts and Congruence
Religions 2017, 8(6), 104; doi:10.3390/rel8060104 (registering DOI) -
Abstract
Is authoritarianism intrinsic to Islam? Is Islam incompatible with democracy? These questions are frequently debated in the context of the study of the relationship between the Western and Islamic civilization. The debate has gained momentum since the last decade of the twentieth century,
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Is authoritarianism intrinsic to Islam? Is Islam incompatible with democracy? These questions are frequently debated in the context of the study of the relationship between the Western and Islamic civilization. The debate has gained momentum since the last decade of the twentieth century, especially after the collapse of the former Soviet Union and the subsequent transition of socialist states in Eastern Europe and other authoritarian states in Asia and Latin America to democracy. The publication of The Clash of Civilizations by American scholar Samuel Huntington, in which he presented a controversial argument about a cultural divide and clash between the Islamic world and the West, pushed the debate even further. Apart from Muslim intellectuals, Western academics have spent a significant amount of time on these questions, with a multitude of articles and volumes examining the compatibility of Islam and democracy. In this paper, we will examine Islam’s relationship with democracy from normative and philosophical viewpoints, examining how the established values and principles of Islam as reflected in the Qur’anic and prophetic traditions correspond to Western democratic norms and practices. In order to obtain a profound understanding of this subject, we have delved into, through content analysis, the thoughts of several early modernist Islamic scholars who have had tremendous impact on contemporary Islamic revivalist movements throughout the world, and interviewed a number of contemporary Islamic thinkers in Bangladesh. Full article
Open AccessArticle
Investigation of Carboxymethyl Cellulose (CMC) on Mechanical Properties of Cold Water Fish Gelatin Biodegradable Edible Films
Foods 2017, 6(6), 41; doi:10.3390/foods6060041 (registering DOI) -
Abstract
The tendency to use biocompatible packages, such as biodegradable films, is growing since they contain natural materials, are recyclable and do not cause environmental pollution. In this research, cold water fish gelatin and carboxymethyl cellulose were combined for use in edible films. Due
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The tendency to use biocompatible packages, such as biodegradable films, is growing since they contain natural materials, are recyclable and do not cause environmental pollution. In this research, cold water fish gelatin and carboxymethyl cellulose were combined for use in edible films. Due to its unique properties, gelatin is widely used in creating gel, and in restructuring, stabilizing, emulsifying, and forming foam and film in food industries. This research for the first time modified and improved the mechanical properties of cold water fish gelatin films in combination with carboxymethyl cellulose. Cold water fish gelatin films along with carboxymethyl cellulose with concentrations of 0%, 5%, 10%, 20% and 50% were prepared using the casting method. The mechanical properties were tested by the American National Standard Method. Studying the absorption isotherm of the resulting composite films specified that the humidity of single-layer water decreased (p < 0.05) and caused a reduction in the equilibrium moisture of these films. In the mechanical testing of the composite films, the tensile strength and Young’s modulus significantly increased and the elongation percent significantly decreased with the increase in the concentration of carboxymethyl cellulose. Considering the biodegradability of the films and the improvement of their mechanical properties by carboxymethyl cellulose, this kind of packaging can be used in different industries, especially the food industry, as an edible coating for packaging food and agricultural crops. Full article
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Open AccessArticle
State Space Models and the Kalman-Filter in Stochastic Claims Reserving: Forecasting, Filtering and Smoothing
Risks 2017, 5(2), 30; doi:10.3390/risks5020030 (registering DOI) -
Abstract
This paper gives a detailed overview of the current state of research in relation to the use of state space models and the Kalman-filter in the field of stochastic claims reserving. Most of these state space representations are matrix-based, which complicates
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This paper gives a detailed overview of the current state of research in relation to the use of state space models and the Kalman-filter in the field of stochastic claims reserving. Most of these state space representations are matrix-based, which complicates their applications. Therefore, to facilitate the implementation of state space models in practice, we present a scalar state space model for cumulative payments, which is an extension of the well-known chain ladder (CL) method. The presented model is distribution-free, forms a basis for determining the entire unobservable lower and upper run-off triangles and can easily be applied in practice using the Kalman-filter for prediction, filtering and smoothing of cumulative payments. In addition, the model provides an easy way to find outliers in the data and to determine outlier effects. Finally, an empirical comparison of the scalar state space model, promising prior state space models and some popular stochastic claims reserving methods is performed. Full article
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Open AccessArticle
Low Frequency Interactive Auralization Based on a Plane Wave Expansion
Appl. Sci. 2017, 7(6), 558; doi:10.3390/app7060558 (registering DOI) -
Abstract
This paper addresses the problem of interactive auralization of enclosures based on a finite superposition of plane waves. For this, room acoustic simulations are performed using the Finite Element (FE) method. From the FE solution, a virtual microphone array is created and an
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This paper addresses the problem of interactive auralization of enclosures based on a finite superposition of plane waves. For this, room acoustic simulations are performed using the Finite Element (FE) method. From the FE solution, a virtual microphone array is created and an inverse method is implemented to estimate the complex amplitudes of the plane waves. The effects of Tikhonov regularization are also considered in the formulation of the inverse problem, which leads to a more efficient solution in terms of the energy used to reconstruct the acoustic field. Based on this sound field representation, translation and rotation operators are derived enabling the listener to move within the enclosure and listen to the changes in the acoustic field. An implementation of an auralization system based on the proposed methodology is presented. The results suggest that the plane wave expansion is a suitable approach to synthesize sound fields. Its advantage lies in the possibility that it offers to implement several sound reproduction techniques for auralization applications. Furthermore, features such as translation and rotation of the acoustic field make it convenient for interactive acoustic renderings. Full article
Open AccessFeature PaperArticle
Identification of Novel Vacuolin-1 Analogues as Autophagy Inhibitors by Virtual Drug Screening and Chemical Synthesis
Molecules 2017, 22(6), 891; doi:10.3390/molecules22060891 (registering DOI) -
Abstract
Autophagy is a fundamental cellular degradation process which is essential for cell homeostasis, and dysfunctional autophagy has been associated with a variety of human diseases, such as cancer. Several autophagy chemical modulators have been applied in a number of preclinical or clinical trials
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Autophagy is a fundamental cellular degradation process which is essential for cell homeostasis, and dysfunctional autophagy has been associated with a variety of human diseases, such as cancer. Several autophagy chemical modulators have been applied in a number of preclinical or clinical trials against these autophagy related diseases, especially cancer. Small molecule vacuolin-1 potently and reversibly inhibits both endosomal-lysosomal trafficking and autophagosome-lysosome fusion, yet the molecular mechanisms underlying vacuolin-1 mediated autophagy inhibition remain unknown. Here, we first performed the virtual drug screening and identified 14 vacuolin-1 analogues as autophagy inhibitors. Based on these virtual screening results, we further designed and synthesized 17 vacuolin-1 analogues, and found that 13 of them are autophagy inhibitors and a couple of them are as potent as vacuolin-1. In summary, these studies expanded the pool of useful autophagy inhibitors and reveal the structural-activity relationship of vacuolin-1 analogues, which is useful for future development of vacuolin-1 analogues with high potency and for identification of the molecular targets of vacuolin-1. Full article
Open AccessArticle
Measurement of Soot Volume Fraction and Temperature for Oxygen-Enriched Ethylene Combustion Based on Flame Image Processing
Energies 2017, 10(6), 750; doi:10.3390/en10060750 (registering DOI) -
Abstract
A method for simultaneously visualizing the two-dimensional distributions of temperature and soot volume fraction in an ethylene flame was presented. A single-color charge-coupled device (CCD) camera was used to capture the flame image in the visible spectrum considering the broad-response spectrum of the
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A method for simultaneously visualizing the two-dimensional distributions of temperature and soot volume fraction in an ethylene flame was presented. A single-color charge-coupled device (CCD) camera was used to capture the flame image in the visible spectrum considering the broad-response spectrum of the R and G bands of the camera. The directional emissive power of the R and G bands were calibrated and used for measurement. Slightly increased temperatures and reduced soot concentration were predicted in the central flame without self-absorption effects considered, an iterative algorithm was used for eliminating the effect of self-absorption. Nine different cases were presented in the experiment to demonstrate the effects of fuel mass flow rate and oxygen concentration on temperature and soot concentration in three different atmospheres. For ethylene combustion in pure-air atmosphere, as the fuel mass flow rate increased, the maximum temperature slightly decreased, and the maximum soot volume fraction slightly increased. For oxygen fractions of 30%, 40%, and 50% combustion in O2/N2 oxygen-enhanced atmospheres, the maximum flame temperatures were 2276, 2451, and 2678 K, whereas combustion in O2/CO2 atmospheres were 1916, 2322, and 2535 K. The maximum soot volume fractions were 4.5, 7.0, and 9.5 ppm in oxygen-enriched O2/N2 atmosphere and 13.6, 15.3, and 14.8 ppm in oxygen-enriched O2/CO2 atmosphere. Compared with the O2/CO2 atmosphere, combustion in the oxygen-enriched O2/N2 atmosphere produced higher flame temperature and larger soot volume fraction. Preliminary results indicated that this technique is reliable and can be used for combustion diagnosis. Full article
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Open AccessArticle
Control Method Based on Demand Response Needs of Isolated Bus Regulation with Series-Resonant Converters for Residential Photovoltaic Systems
Energies 2017, 10(6), 752; doi:10.3390/en10060752 (registering DOI) -
Abstract
Considering the effects of isolation and high efficiency, a series-resonant DC-DC converter (L-L-C type, with two inductors and a capacitor) has been introduced into a residential photovoltaic (PV) generation and storage system in this work, and a voltage gain curve upwarp drifting problem
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Considering the effects of isolation and high efficiency, a series-resonant DC-DC converter (L-L-C type, with two inductors and a capacitor) has been introduced into a residential photovoltaic (PV) generation and storage system in this work, and a voltage gain curve upwarp drifting problem was found. In this paper, the reason of upwarp drifting in the voltage gain curve is given, and a new changing topological control method to solve the voltage regulation problem under light load conditions is proposed. Firstly, the ideal and actual first harmonic approximation (FHA) models are given, and this drifting problem is ascribed to the multiple peaks of higher-order resonance between resonant tank and parasitic capacitors. Then the paper presents the pulse-frequency-modulation (PFM) driver signals control method to translate the full-bridge LLC into a half-bridge LLC converter, and with this method the voltage gain could easily be reduced by half. Based on this method, the whole voltage and resonant current sharing control methods in on-line and off-line mode are proposed. The parameters design and optimization methods are also discussed in detail. Finally, a residential PV system platform based on the proposed parallel 7-kW full-bridge LLC converter is built to verify the proposed control method and theoretical analysis. Full article
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