bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Anatomy of Ovules in Galinsoga, Solidago and Ratibida (Asteraceae)
Authors: Kolczyk Jolanta , Stolarczyk Piotr , Płachno Bartosz J.
Published: May 2015

Many Asteraceae species have been introduced into horticulture as ornamental or interesting exotic plants. Some of them, including Solidago and Galinsoga, are now aggressive weeds; others such as Ratibida are not. Special modifications of the ovule tissue and the occurrence of nutritive tissue have been described in several Asteraceae species, including invasive Taraxacum species. This study examined whether such modifications might also occur in other genera. We found that the three genera examined - Galinsoga (G. quadriradiata), Solidago (S. canadensis, S. rigida, S. gigantea) and Ratibida (R. pinnata) - differed in their nutritive tissue structure. According to changes in the integument, we identified three types of ovules in Asteraceae: “Taraxacum” type (recorded in Taraxacum, Bellis, Solidago, Chondrilla), with well-developed nutritive tissue having very swollen cell walls of spongy structure; “Galinsoga” type (in Galinsoga), in which the nutritive tissue cells have more cyto-plasm and thicker cell walls than the other integument parenchyma cells, and in which the most prominent character of the nutritive tissue cells is well-developed rough ER; and “Ratibida” type (in Ratibida), in which the nutritive tissue is only slightly developed and consists of large highly vacuolated cells. Our study and future investigations of ovule structure may be useful in phylogenetic analyses.
Interaction Between Photoreceptors and BR Signaling in Arabidopsis
Authors: Zhu Zhong Xin , Zhu Xiao Feng , Zhu Yu Ting , Yao Da Nian , Xuan Yuan Hu
Published: May 2015

Extensive studies have been performed to elucidate the role of brassinosteroids (BRs), an important class of phy-tohormone in plant growth, development, and photomorphogenesis. Different wavelengths of light recognized by photoreceptors play a crucial role in plant development. The role of different photoreceptors in BR signaling has not been analyzed. Here we used photoreceptor single mutants, double mutants and even a quadruple mutant to analyze BR-dependent hypocotyl growth and gene regulation. All the photoreceptor mutants differed from the controls in their response to BR, and hypocotyl elongation as well as BR marker gene regulation were inhibited by application of propiconazole (PCZ), a BR biosynthesis inhibitor. In addition, altered Phytochrome and Cryptochrome expression in brassinosteroid insensitive 1 mutant bri1-5 and brassinazole-resistant 1 dominant mutant bzr1-D indicated that BR negatively regulates photoreceptors in transcriptional levels. This is the first study to investigate the connections between BR and photoreceptors in Arabidopsis.
Growth Improvement of Nicotiana and Arabidopsis In Vitro by Microalgal Conditioned Media
Authors: Zielińska Elżbieta , Matusiak-Mikulin Krystyna , Grabski Krzysztof , Heda Anna , Krzykowska Aleksandra , Tukaj Zbigniew
Published: May 2015

Conditioned medium (CM) is a general term describing media in which cells have already been cultivated for some time. Such media, usually clarified by filtration, have been used by plant biotechnologists as additives sup-porting the growth of cell suspensions, organs and whole plants. This study examined the effect of CM obtained from green alga Desmodesmus subspicatus on the growth and functioning of the photosynthetic apparatus of Nicotiana tabacum and Arabidopsis thaliana in culture in vitro. Plants where cultured on CM diluted 1.25-, 2-and 5-fold with MS medium. The increase in fresh and dry weight was highest in tobacco and Arabidopsis cultured on CM/2 and CM/1.25 media. Those two concentrations also increased the amount of chlorophylls in both plants tested. CM improved parameter PI (reflecting the photosynthetic “vitality” of the organism) and electron transport efficiency, and increased the fraction of active reaction centers. Analysis of chlorophyll fluorescence in vivo suggests that the improvement of these plants grown in the presence of algal CM may result from stimulation of photosynthesis. Algal CM offers a convenient, cheap, universal supplement for stimulating the growth of higher plants in vitro.
A Comparison of Machine Learning Methods in a High-Dimensional Classification Problem
Authors: Zekić-Sušac Marijana , Pfeifer Sanja , Šarlija Nataša
Published: May 2015

Background: Large-dimensional data modelling often relies on variable reduction methods in the pre-processing and in the post-processing stage. However, such a reduction usually provides less information and yields a lower accuracy of the model. Objectives: The aim of this paper is to assess the high-dimensional classification problem of recognizing entrepreneurial intentions of students by machine learning methods. Methods/Approach: Four methods were tested: artificial neural networks, CART classification trees, support vector machines, and k-nearest neighbour on the same dataset in order to compare their efficiency in the sense of classification accuracy. The performance of each method was compared on ten subsamples in a 10-fold cross-validation procedure in order to assess computing sensitivity and specificity of each model. Results: The artificial neural network model based on multilayer perceptron yielded a higher classification rate than the models produced by other methods. The pairwise t-test showed a statistical significance between the artificial neural network and the k-nearest neighbour model, while the difference among other methods was not statistically significant. Conclusions: Tested machine learning methods are able to learn fast and achieve high classification accuracy. However, further advancement can be assured by testing a few additional methodological refinements in machine learning methods.
Social norms and cultural services - community belief system and use of wildlife products in the Northern periphery of the Korup National Park, South-West Cameroon
Authors: Ngoufo R , Yongyeh NK , Obioha EE , Bobo KS , Jimoh SO , Waltert M
Published: May 2015

In many traditional societies, beliefs and taboos influence human behaviour towards the natural environment. Such beliefs and taboos are informal institutions where norms rather than official laws determine land use and nature protection in general and wildlife in particular. The present study on beliefs and taboos of the people of the northern periphery of the Korup National Park is an attempt to reveal how norms influence their relation to the environment. A total of 195 households were sampled through a household survey conducted in four villages. The results revealed that before the application of “modern” approaches for wildlife protection and management, the people relied on norms to establish a relationship with wildlife and nature. The enactment of the 1994 legislation on forest, wildlife and fisheries resulted in stiff resistance as it contradicts traditional norms. It was found that 57.4 % of the respondents still perceive wildlife as a resource that can never get extinct. Traditional norms had a differentiated impact especially on game protection. The study recommends that a wildlife benefiting code of beliefs and taboos is developed to provide a basis for establishing a synergy between park management laws and traditional belief/taboo systems that drive the management of wildlife.
Ecosystem Services – Examples of Their Valuation Methods in Czech Republic and Slovakia
Authors: Sarvašová Zuzana , Kovalčík Miroslav , Dobšinská Zuzana , Šálka Jaroslav , Jarský Vilém
Published: May 2015

This literature review deals with the understanding of ecosystem services related to the question of their applicability and appropriate methods for their valuation. We distinguish between ecological valuation methods that aim to assess the significance of landscape characteristics, conventional economic, i.e. monetary valuation and non-monetizing valuation or assessment. Ecological evaluation methods derive values by following a cost of production approach which neglects consumer preferences. Economic valuation methods focus on the exchange value of ecosystem services, i.e. they are based on consumer preferences, but do not adequately take into account the complex internal structure of ecosystems. We conclude that – from the view of implementation of ecosystem services for policy support and consulting – successful valuation approaches should particularly consider the relationships between economic, ecological and social aspects of ecosystem services’ provision.
Comparative Study of Cigarette Smoke Cytotoxicity Using Two In Vitro Assay Systems
Authors: Fukushima Toshiro , Tanaka Hitomi , Yamamoto Takeshi
Published: May 2015

The aim of this study was to compare the results obtained from two in vitro cytotoxicity assays that depend upon different mechanisms/modes of action. The Neutral Red Uptake (NRU) assay is based on endocytotic activity whereas the Water Soluble Tetrazolium Salts (WST-1) assay is based on mitochondrial dehydrogenase activity. Both were investigated in light of their wide use and documented validation. The total particulate matter (TPM) and gas vapor phase (GVP) of main stream smoke derived from Kentucky reference cigarettes 3R4F and 10 test cigarettes made of 100% flue-cured or 100% Burley tobacco were individually applied to the two assays using CHO-K1 cells. In addition, cigarette smoke constituents and known cytotoxic agents, documented to affect specific endpoints, were evaluated within both assays. Although the NRU assay was primarily more sensitive than the WST-1 assay, both assays provided comparable results in terms of the rank order for the cytotoxicity of cigarette smoke samples. In addressing the cytotoxicity of constituents in cigarette smoke, acrolein, hydroquinone and catechol gave clear dose-related decreases in cell viability (an end point common in both assays). Moreover, enzyme inhibitors of the mitochondrial respiratory chain and chemicals causing membrane disruption also showed similar responses regardless of the specific endpoint addressed within the cytotoxicity assay. In conclusion, results from the NRU and WST-1 assay are comparable therefore indicating results were independent of the different assay detection mechanisms/modes of action. [Beitr. Tabakforsch. Int. 26 (2014) 98-108]
Comparative Structural Analysis of Flexible Pavements Using Finite Element Method
Authors: Gupta Ankit , Kumar Abhinav
Published: May 2015

The evaluation of bituminous concrete mixes for their tendency to rutting has been an important research field for many years. Rutting is a major type of distress encountered in bituminous pavements. The Finite Element Method (FEM) is a numerical analysis technique to obtain various structural parameters such as stress, strain and deflection of pavement layers. The objective of this paper is to study the sensitivity of these variables in reducing the vertical surface deflections, the critical tensile strains at the bottom of the bitumen layer and the critical compressive strains on the top of subgrade using the finite element method. This study has been carried out in order to compare the performance of flexible pavement using the finite element method and KENLAYER. Vertical surface deflections in flexible pavements have always been a major concern and are used as a criterion for pavement design. It is desirable to reduce the deflections as much as possible. This paper deals with ways to reduce deflections by varying the design configuration, such as increasing the Hot Mix Asphalt (HMA) modulus, the base modulus, sub base modulus and the subgrade modulus. Another objective of the present study is to investigate the effectiveness of two different methods in reducing vertical surface deflections (wo) and the critical tensile strains in the bitumen layer (εt) or the radial strains at the bottom layer of HMA. The finite element method was adopted to evaluate the effectiveness of the two methods and the sensitivity of various factors
Multi-Objective Optimization of Vehicle Suspension Parameters Considering Various Road Classes
Authors: Havelka Ferdinand , Musil Miloš
Published: May 2015

Vehicle suspension optimization for various road classes travelled at different velocities is performed. Road excitation is modeled using a first order shaping filter. A half-car model is adopted to simulate the vehicle’s vertical dynamics. The excitation time delay between the rear and the front tire is modeled using Pade approximation. Suspension parameters are optimized using a random search method with respect to “comfort” and “sporty driving” considering the design constraints of the suspension and road holding and maximum suspension travel constraints. Optimal suspension parameters suitable for various road classes and vehicle velocities have been chosen.
Active Displacement Control of Active Magnetic Bearing System
Authors: Kertész Milan , Kozakovič Radko , Magdolen Luboš , Masaryk Michal
Published: May 2015

The worldwide energy production nowadays is over 3400 GW while storage systems have a capacity of only 90 GW [1]. There is a good solution for additional storage capacity in flywheel energy storage systems (FES). The main advantage of FES is its relatively high efficiency especially with using the active magnetic bearing system. Therefore there exist good reasons for appropriate simulations and for creating a suitable magneto-structural control system. The magnetic bearing, including actuation, is simulated in the ANSYS parametric design language (APDL). APDL is used to create the loops of transient simulations where boundary conditions (BC) are updated based upon a “gap sensor” which controls the nodal position values of the centroid of the shaft and the current density inputs onto the copper windings.
Programming System for the Applications of Deployment Methods in an Engineering Company
Authors: Komák Martin , Králik Marian
Published: May 2015

This paper describes a software system for the application of spacing methods in engineering companies. As input, the system uses the material flows of the planned production. The solution is based on the triangle net method, which has been modified in this design. The main idea of the modifications of this method is to create a system that would locate each machine workplace based on a comparison and evaluation of all the possible locations in the given space. The system offers the possibility of creating a custom database of machine workplaces. The graphical output shows how the machine workplaces are spaced and the materials flow between them.
Research of HCR Gearing Properties from Warm Scuffing Damage Point of View
Authors: Kuzmanović Siniša , Rackov Milan , Vereš Miroslav , Krajčovič Adam
Published: May 2015

The issue of design and dimensioning of HCR gearing, particularly of the gearings with an internal engagement, it nowadays, especially in the design of hybrid cars drives, highly topical. This kind of gearing has many advantages in operation, but at the same time it is more complicated in stage of its design and load capacity calculation. Authors in this contribution present some results of temperature scuffing research of internal and external HCR gearing. There are given the equations for calculation of warm scuffing resistance of both external and internal HCR gearing derived according to the integral temperature criterion.
Study of Laser Welding of HCT600X Dual Phase Steels
Authors: Švec Pavol , Hrnčiar Viliam , Schrek Alexander
Published: May 2015

The effects of beam power and welding speed on microstructure, microhardnes and tensile strength of HCT600X laser welded steel sheets were evaluated. The welding parameters influenced both the width and the microstructure of the fusion zone and heat affected zone. The welding process has no effect on tensile strength of joints which achieved the strength of base metal and all joints fractured in the base metal.
Kristeva, Ethics and Intellectual Practice
Authors: Gambaudo Sylvie
Published: May 2015

The aim of this article is to revisit the work of the French philosopher Julia Kristeva and ask what place we might give her conceptual framework today. I will focus on one key aspect of Kristeva’s work, sexual difference, as that which ties most, if not all, aspects of Kristeva’s work. I am hoping to present a concise, yet wide-ranging view on Kristeva’s critical contribution to the fields of politics and ethics. My objective will be threefold. First, I will present the main lines of Kristeva’s theory on sexual difference; this presentation will also outline her political critique of equality and diversity in the domains of gender and sexuality. Kristeva believes that contemporary politics invested in suppressing inequality through the promotion of diversity will in the long term not only prove unsuccessful, but also create more exclusion. Secondly, I will point out the main objections raised against her theories and show how her critics come to their conclusions. Objectors to Kristeva’s sexual difference theory are mostly concerned with the manner in which she associates marginality and unintelligibility. They see little value in her theory, because, on the one hand, it relegates marginal groups to a world beyond social viability, and, on the other, because it effectively disables advancements in equality politics. Finally, I hope to provide the reader with a useful counter-critique to Kristeva’s detractors that will show why their views are partly founded on a misreading of her ethical (Freudian) framework and a desire to translate her work into a more pragmatic and user-friendly tool. I will argue that Kristeva’s work is best apprehended as a variant of psychoanalytic ethics and that to engage with its rhetoric is to capture the full weight of Kristeva’s contribution to politics and intellectual engagement.
The use of holiday biography in generation-based ‘tourism space’ research
Authors: Kowalczyk-Anioł Joanna
Published: May 2015

The article presents the concept of generation-based ‘tourism space’ research using the holiday biography method. The author refers to her earlier research conducted among three generations of Łodź families. She discusses the biography method used in the research and approaches it from a geo-biographical point of view, showing possible ways of recording the phenomenon (the particular character of the source material collected) and the various options available at later stages of research – interpretation (choosing the analysis, measurement and presentation methods) – and generalization.
Museums in cultural tourism in Poland
Authors: Krakowiak Beata
Published: May 2015

The article presents the museums, their potential and their significance for cultural tourism in Poland. Its aims are achieved through a presentation of registered national museums, ‘monuments of history’, museum buildings and the cultural activities undertaken by these institutions.
The Analytical Description of Regular LDPC Codes Correcting Ability
Authors: Uryvsky Leonid , Osypchuk Serhii
Published: May 2015

The analytical description of regular LDPC (Low-Density Parity Check) codes correcting ability has been investigated. The statistical dependencies for the maximum number of corrected bits per the code word as a function of LDPC code word length and code rate are given based on multiple experimental analyses of LDPC check matrices. The analytical expressions are proposed for the cases of linear, exponential and polynomial approximations of given results. The most exact analytical formula is proved by criterion of the minimum divergence between the experimental and theoretical results.
Digital Advertising System in Urban Transport System of Žilina Town
Authors: Madleňák Radovan , Madleňáková Lucia
Published: May 2015

The Internet and information and communication technologies (ICT) have changed everything: news, commerce, advertising, relating to others, getting information and transport too. It has changed how the people work, how they practice religion, how they date, how they spend the free time and how they travel. One of the technological innovations that are based on usage ICT in advertising space is digital signage. This article presents the results of research dedicated to investigate the relationships between customers-passengers and this new ICT technology in real environment. The results of the research stimulate the discussion about the future advertising practices in Žilina town. Based on the wide analysis of opportunities the digital signage technology in advertising practices, the presented marketing research investigates how passengers accept virtual advertising technology in urban transport system of Žilina town. Authors highlight the advantages of interactivity between digital signage technology and consumers. The conclusions of this article triggers further investigations in the area of the interactions between the digital advertising technology and passengers, and the passengers’ perception and acceptation of shopping activities on the basis of advertising in digital signage medias.
Analysis of Intra-Urban Traffic Accidents Using Spatiotemporal Visualization Techniques
Authors: Soltani Ali , Askari Sajad
Published: May 2015

Road traffic accidents (RTAs) rank in the top ten causes of the global burden of disease and injury, and Iran has one of the highest road traffic mortality rates in the world. This paper presents a spatiotemporal analysis of intra-urban traffic accidents data in metropolitan Shiraz, Iran during the period 2011-2012. It is tried to identify the accident prone zones and sensitive hours using Geographic Information Systems (GIS)-based spatio-temporal visualization techniques. The analysis aimed at the identification of high-rate accident locations and safety deficient area using Kernel Estimation Density (KED) method. The investigation indicates that the majority of occurrences of traffic accidents were on the main roads, which play a meta-region functional role and act as a linkage between main destinations with high trip generation rate. According to the temporal distribution of car crashes, the peak of traffic accidents incident is simultaneous with the traffic congestion peak hours on arterial roads. The accident-prone locations are mostly located in districts with higher speed and traffic volume, therefore, they should be considered as the priority investigation locations to safety promotion programs.
Adaptive Technology Application for Vibration-Based Diagnostics of Roller Bearings on Industrial Plants
Authors: Mironov Aleksey , Doronkin Pavel , Priklonskiy Alexander , Yunusov Sergey
Published: May 2015

Roller bearings are widely used in equipment of different applications; therefore, the issues related to the assessment of bearing technical state and localization of bearing faults are quite important and relevant. The reason is that technical state of a bearing is a critical component, which determines efficiency of a mechanism or equipment. For bearings inspection and diagnostics, various methods of vibration-based diagnostics are used. The adaptive technology for vibration-based diagnostics developed in „D un D centrs” is an effective tool for evaluation of technical state of bearings in operation compared to the existing SKF method.
Optimization of Decision-Making in Port Logistics Terminals: Using Analytic Hierarchy Process for the Case of Port of Thessaloniki
Authors: Gogas Michael , Papoutsis Konstantinos , Nathanail Eftihia
Published: May 2015

The management models pursued in logistics terminals determine their performance to a great extent. Terminals managed by public actors usually incorporate more social criteria into their decision-making processes. In addition, private management focuses on economic viability of the initiative. Decision-making is a complex process regardless the structure of management or the decision models useddue to the fact that a wide range of diverse criteria are embedded into this process. The objective of this paper it to determine a prioritization of a set of alternative options for investment projects which were suggested by port executives taking into account criteria and evaluation that have already validated by them. In order to perform the analysis a multi-criteria decision-making model was used: the Analytic Hierachy Process. The outcomes support a low-biased and efficient strategic planning through a balanced decision-making framework.
Road Traffic Measurement and Related Data Fusion Methodology for Traffic Estimation
Authors: Tettamanti Tamás , Horváth Márton Tamás , Varga István
Published: May 2015

The knowledge of road traffic parameters is of crucial importance to ensure state-of-the-art traffic services either in public or private transport. In our days, a plethora of road traffic data are continuously collected producing historical and real-time traffic information as well. The available information, however, arrive from inhomogeneous sensor systems. Therefore, a data fusion methodology is proposed based on Switching Kalman Filter. The concept enables efficient travel time estimation for urban road traffic network. On the other hand, the method may contribute to a better macroscopic traffic modelling.
Usage of Production Functions in the Comparative Analysis of Transport Related Fuel Consumption
Authors: Torok Adam , Torok Arpad , Heinitz Florian
Published: May 2015

This contribution aims to examine the relationship between the transport sector and the macroeconomy, particularly in fossil energy use, capital and labour relations. The authors have investigated the transport related fossil fuel consumption 2003 -2010 in a macroeconomic context in Hungary and Germany. The Cobb-Douglas type of production function could be justified empirically, while originating from the general CES (Constant Elasticity of Substitution) production function. Furthermore, as a policy implication, the results suggest that a solution for the for the reduction of anthropogenic CO2 driven by the combustion of fossil fuels presupposes technological innovation to reach emission reduction targets. Other measures, such as increasing the fossil fuel price by levying taxes, would consequently lead to an undesirable GDP decline.
Culturally Responsive Experimental Intervention Studies
Authors: Bal Aydin , Trainor Audrey A.
Published: May 2015

Neither legislative demand for evidence-based practices nor a focus on experimental designs for educational interventions has ameliorated the disparate educational opportunities and outcomes for youth from nondominant cultural and linguistic backgrounds. Recent initiatives to increase the rigor of intervention research in special education have largely ignored the implications of culture and its role in experimental research. The extent to which the experimental intervention studies are culturally responsive remains unexplored. We developed a rubric, modeled after prior rubrics for quality indicators of special education research, identifying criteria for culturally responsive research. Rubric items were created following a systematic review of literature and gathering feedback from experts. The 15-item rubric uses culture as a generative concept that mediates each aspect of experimental intervention research. Implications include expanding the field’s dominant empirical paradigm and increasing reflexivity and responsivity in knowledge production that may contribute to a paradigm expansion in special education research.
Retrospective comparison of decompressive hemicraniectomy and hematoma evacuation for spontaneous supratentorial intracerebral hematoma
Authors: Joarder MA , Karim AKMB , Kamal T , Sujon T , Akhter N , Islam K , Hossain MZ , Mollik A , Sultana S , Shankar DRK , Jahangir SM , Chandy M
Published: May 2015

Objectives: The aim of this study was to test the hypothesis that decompressive hemicraniectomy (DHC), compared with craniotomy with evacuation of hematoma, and would improve clinical outcomes of patients with supratentorial intracerebral hemorrhage (SICH).Methods: We compared patients (November 2008February 2014) with supratentorial ICH treated with DHC without hematoma evacuation and craniotomy with hematoma evacuation. DHC measured at least 150 mm and included opening of the dura. We analyzed clinical, radiological, and surgical characteristics. Outcome at 6 months was divided into good (modified Rankin Scale 04) and poor (modified Rankin Scale 56).Results: Fifteen patients (mean age 58 years) with ICH were treated by DHC. Median hematoma volume was 61 ml and mean preoperative Glasgow Coma Scale (GCS) was 7. Ten patients had good and five had poor outcomes. In hematoma evacuation group 29 patients were treated. Median hematoma volume was 55 ml and mean preoperative Glasgow Coma Scale (GCS) was 8. Seventeen patients had good and twelve had poor outcomes.Conclusions: DHC is more effective than hematoma evacuation in patients with SICH. Based on this small cohort, DHC may reduce mortality. Larger prospective study is warranted to assess safety and efficacy.Pulse Vol.7 January-December 2014 p.16-21
An Adaptive Spectral Clustering Algorithm Based on the Importance of Shared Nearest Neighbors
Authors: He Xiaoqi , Zhang Sheng , Liu Yangguang
Published: May 2015

The construction of a similarity matrix is one significant step for the spectral clustering algorithm; while the Gaussian kernel function is one of the most common measures for constructing the similarity matrix. However, with a fixed scaling parameter, the similarity between two data points is not adaptive and appropriate for multi-scale datasets. In this paper, through quantitating the value of the importance for each vertex of the similarity graph, the Gaussian kernel function is scaled, and an adaptive Gaussian kernel similarity measure is proposed. Then, an adaptive spectral clustering algorithm is gotten based on the importance of shared nearest neighbors. The idea is that the greater the importance of the shared neighbors between two vertexes, the more possible it is that these two vertexes belong to the same cluster; and the importance value of the shared neighbors is obtained with an iterative method, which considers both the local structural information and the distance similarity information, so as to improve the algorithm’s performance. Experimental results on different datasets show that our spectral clustering algorithm outperforms the other spectral clustering algorithms, such as the self-tuning spectral clustering and the adaptive spectral clustering based on shared nearest neighbors in clustering accuracy on most datasets.
Excess Phase Noise Characterization in Multifrequency Remote Clock Distribution Based on Femtosecond Frequency Combs
Authors: Hu Changjun , Gollapalli Ravi , Yang Lin , Duan Lingze
Published: May 2015

Remote distribution of optical frequency references, based on multifrequency sources such as femtosecond frequency combs, holds many advantages over its single-frequency counterpart. However, characterizing the excess noise caused by the transmission links or external perturbations in a multifrequency scheme posts new challenges. We have experimentally demonstrated direct measurement of excess phase noise spectrum in both free-space and fiber-optic transfer of a frequency comb using a multiheterodyne technique. In fiber-optic distribution, we focused on the excess phase noise under a single-tone acoustic perturbation. Increased overall noise power and a change of phase noise spectrum have been observed. In free-space distribution, a fractional instability of 3 × 10−14 at 1 s was observed for a 60 m outdoor atmospheric transmission, and large phase modulation due to air fluctuations causes a sizable line broadening.
AIM for Allostery: Using the Ising Model to Understand Information Processing and Transmission in Allosteric Biomolecular Systems
Authors: LeVine Michael , Weinstein Harel
Published: May 2015

In performing their biological functions, molecular machines must process and transmit information with high fidelity. Information transmission requires dynamic coupling between the conformations of discrete structural components within the protein positioned far from one another on the molecular scale. This type of biomolecular “action at a distance” is termed allostery. Although allostery is ubiquitous in biological regulation and signal transduction, its treatment in theoretical models has mostly eschewed quantitative descriptions involving the system’s underlying structural components and their interactions. Here, we show how Ising models can be used to formulate an approach to allostery in a structural context of interactions between the constitutive components by building simple allosteric constructs we termed Allosteric Ising Models (AIMs). We introduce the use of AIMs in analytical and numerical calculations that relate thermodynamic descriptions of allostery to the structural context, and then show that many fundamental properties of allostery, such as the multiplicative property of parallel allosteric channels, are revealed from the analysis of such models. The power of exploring mechanistic structural models of allosteric function in more complex systems by using AIMs is demonstrated by building a model of allosteric signaling for an experimentally well-characterized asymmetric homodimer of the dopamine D2 receptor.
Multi-Period Optimization Model for Electricity Generation Planning Considering Plug-in Hybrid Electric Vehicle Penetration
Authors: Ahmadi Lena , Elkamel Ali , Abdul-Wahab Sabah , Pan Michael , Croiset Eric , Douglas Peter , Entchev Evgueniy
Published: May 2015

One of the main challenges for widespread penetration of plug-in hybrid electric vehicles (PHEVs) is their impact on the electricity grid. The energy sector must anticipate and prepare for this extra demand and implement long-term planning for electricity production. In this paper, the additional electricity demand on the Ontario electricity grid from charging PHEVs is incorporated into an electricity production planning model. A case study pertaining to Ontario energy planning is considered to optimize the value of the cost of the electricity over sixteen years (2014–2030). The objective function consists of the fuel costs, fixed and variable operating and maintenance costs, capital costs for new power plants, and the retrofit costs of existing power plants. Five different case studies are performed with different PHEVs penetration rates, types of new power plants, and CO2 emission constraints. Among all the cases studied, the one requiring the most new capacity, (~8748 MW), is assuming the base case with 6% reduction in CO2 in year 2018 and high PHEV penetration. The next highest one is the base case, plus considering doubled NG prices, PHEV medium penetration rate and no CO2 emissions reduction target with an increase of 34.78% in the total installed capacity in 2030. Furthermore, optimization results indicate that by not utilizing coal power stations the CO2 emissions are the lowest: ~500 tonnes compared to ~900 tonnes when coal is permitted.
Simulation of Distributed Generation with Photovoltaic Microgrids—Case Study in Brazil
Authors: Xavier Gustavo , Filho Delly , Martins José , Monteiro Paulo , Diniz Antônia
Published: May 2015

Elevated prices and lack of proper legislation and government incentives have been the main barriers in the development of the photovoltaic market in Brazil. In an attempt to overcome those barriers, a microgrid model was proposed and simulated. In the proposed microgrids, residential consumers are connected to each other to maximize the investment return by trading the surplus of generated energy among them. Different topologies and scenarios were studied from electrical energy and economic standpoints. Stochastic data of solar radiation were simulated for the city of Viçosa, Minas Gerais, Brazil, for the period of one year, considering the statistical behavior of a series over 20 years. The system output power and energy balance were calculated considering a model for photovoltaic generators and the radiation simulated data. By determining the generated energy and electrical needs of the microgrid members, the cash flow and economic feasibility were calculated. Sensitivity analyses were performed by varying economic parameters to determine situations where investment becomes feasible. This paper shows that microgrid contributes to improve the economics and the initial investments. The number of participants in a microgrid, the electricity and the equipment costs are important parameters to speed up the economic and technical feasibility process.
Assessment of Wooded Area Reduction by Airborne Laser Scanning
Authors: Tran Thi , Hollaus Markus , Nguyen Ba , Pfeifer Norbert
Published: May 2015

Airborne Laser Scanning (ALS) data hold a great deal of promise in monitoring the reduction of single trees and forests with high accuracy. In the literature, the canopy height model (CHM) is the main input used frequently for forest change detection. ALS also has the key capability of delivering 3D point clouds, not only from the top canopy surface, but also from the entire canopy profile and also from the terrain. We investigated the use of two additional parameters, which exploit these capabilities for assessing the reduction of wooded area: Slope-adapted echo ratio (sER) and Sigma0. In this study, two ALS point cloud data sets (2005 and 2011) were used to calculate Digital Surface Model (DSM), sER, and Sigma0 in 1.5 km2 forest area in Vorarlberg, Austria. Image differencing was applied to indicate the change in the three difference models individually and in their combinations. Decision trees were used to classify the area of removed trees with the minimum mapping unit of 13 m2. The final results were evaluated by a knowledge-based manual digitization using completeness and correctness measures. The best result is achieved using the combination of sER and DSM, namely a correctness of 92% and a completeness of 85%.
Lung Function Impact from Working in the Pre-Revolution Libyan Quarry Industry
Authors: Draid Marwan , Ben-Elhaj Khaled , Ali Ashraf , Schmid Kendra , Gibbs Shawn
Published: May 2015

The purpose of this study was to determine the lung impact from working within the Libyan quarry industry, and if the length of work impacted the degree of degradation. Eighty three workers from eight silica quarries in the Nafusa Mountains of Libya opted to participate. These quarries were working the upper cretaceous geological structure. Eighty-five individuals who lived in Gharyan City with no affiliation to quarry operations participated as controls. Spirometry variables evaluated were Forced Vital Capacity (FVC), Forced Expiratory Volume at 1.0 second (FEV1), FVC/FEV1 and Peak Expiratory Flow (PEF). Control and exposed groups had no differences in terms of height, weight, or smoking status (p = 0.18, 0.20, 0.98, respectively). Prior to adjustment for other variables, FVC, FEV1, and PEF are all significantly lower in the exposed group (p = 0.003, 0.009, 0.03, respectively). After adjustment for age, height, weight, and smoking status, there remain significant differences between the control and exposed groups for FVC, FEV1, and PEF. This analysis demonstrated that exposure to quarry dust has a detrimental effect on lung function, and that pre-revolution Libyan quarry workers were being exposed. This study shows that any exposure is harmful, as the reduction in lung function was not significantly associated with years of exposure.
5-ALA Fluorescence Image Guided Resection of Glioblastoma Multiforme: A Meta-Analysis of the Literature
Authors: Eljamel Samy
Published: May 2015

Background: Glioblastoma multiforme (GBM) is one of the most deadly cancers in humans. Despite recent advances in anti-cancer therapies, most patients with GBM die from local disease progression. Fluorescence image guided surgical resection (FIGR) was recently advocated to enhance local control of GBM. This is meta-analyses of 5-aminolevulinic (5-ALA) induced FIGR. Materials: Review of the literature produced 503 potential publications; only 20 of these fulfilled the inclusion criteria of this analysis, including a total of 565 patients treated with 5-ALA-FIGR reporting on its outcomes and 800 histological samples reporting 5-ALA-FIGR sensitivity and specificity. Results: The mean gross total resection (GTR) rate was 75.4% (95% CI: 67.4–83.5, p < 0.001). The mean time to tumor progression (TTP) was 8.1 months (95% CI: 4.7–12, p < 0.001). The mean overall survival gain reported was 6.2 months (95% CI: −1–13, p < 0.001). The specificity was 88.9% (95% CI: 83.9–93.9, p < 0.001) and the sensitivity was 82.6% (95% CI: 73.9–91.9, p < 0.001). Conclusion: 5-ALA-FIGR in GBM is highly sensitive and specific, and imparts significant benefits to patients in terms of improved GTR and TTP.
Novel All Trans-Retinoic Acid Derivatives: Cytotoxicity, Inhibition of Cell Cycle Progression and Induction of Apoptosis in Human Cancer Cell Lines
Authors: Al-Sheddi Ebtesam , Al-Oqail Mai , Saquib Quaiser , Siddiqui Maqsood , Musarrat Javed , Al-Khedhairy Abdulaziz , Farshori Nida
Published: May 2015

Owing to the pharmacological potential of ATRA (all trans-retinoic acid), a series of retinamides and a 1-(retinoyl)-1,3-dicyclohexylurea compound were prepared by reacting ATRA with long chain alkyl or alkenyl fatty amines by using a 4-demethylaminopyridine (DMAP)-catalyzed N,N¢-dicyclohexylcarbodiimide (DCC) coupling. The successful synthesis of the target compounds was demonstrated using a range of spectroscopic techniques. The cytotoxicity of the compounds was measured along with their ability to induce cell cycle arrest and apoptosis in human cancer cell lines MCF-7 (breast cancer) and HepG2 (liver cancer) and normal human cell line HEK293 (embryonic kidney). The results of cytotoxicity and flow cytometry data showed that the compounds had a moderate to strong effect against MCF-7 and HepG2 cells and were less toxic to HEK293 cells. N-oleyl-retinamide was found to be the most potent anticancer agent and was more effective against MCF-7 cells than HepG2 cells.
Toward Super-Resolution Imaging at Green Wavelengths Employing Stratified Metal-Insulator Metamaterials
Authors: Iwanaga Masanobu
Published: May 2015

Metamaterials (MMs) are subwavelength-structured materials that have been rapidly developed in this century and have various potentials to realize novel phenomena, such as negative refraction, cloaking and super-resolution. Theoretical proposals for super-resolution image transfer using metallic thin films were experimentally demonstrated at ultraviolet and violet wavelengths from 365 to 405 nm. However, the most preferred wavelengths of optical imaging are green wavelengths around 500 nm, because optical microscopy is most extensively exploited in the area of biotechnology. In order to make the super-resolution techniques using MMs more practical, we propose the design of a stratified metal-insulator MM that has super-resolution image transfer modes at green wavelengths, which we here call hyper modes. The design assumed only Ag and SiO2 as constituent materials and was found employing Bloch-state analysis, which is based on a rigorous transfer-matrix method for the metal-insulator MMs. It is numerically substantiated that the designed stratified metal-insulator metamaterial (SMIM) is capable of forming super-resolution images at the green wavelengths, and optical loss reduction is also studied. We discuss the results derived by the Bloch-state analysis and by effective medium models usually used for the metal-insulator MMs and show that the Bloch-state analysis is more suitable to reproduce the experimental data.
The Application of Dielectric Spectroscopy and Biocalorimetry for the Monitoring of Biomass in Immobilized Mammalian Cell Cultures
Authors: Cole Harriet , Demont Aurélie , Marison Ian
Published: May 2015

The purpose of this study was to introduce dielectric spectroscopy and biocalorimetry as monitoring methods to follow immobilised Chinese Hamster Ovary (CHO) cell culture development. The theory behind both monitoring techniques is explained and perfusion cultures are performed in a Reaction Calorimeter (eRC1 from Mettler Toledo) as an application example. The findings of this work show that dielectric spectroscopy gives highly reliable information upon the viable cell density throughout the entire culture. On the other hand, the RC1 could only provide accurate data from day 5, when the cell density exceeded 4 × 106 vcells∙mL−1 (viable cell per mL) working volume (WV). The method validation showed the limit of detection (LOD) for 1.4 L cultures to be 8.86 × 106 vcells∙mL−1, a viable cell density commonly achieved in fed-batch and the early stages of a perfusion culture. This work suggests that biocalorimetry should be possible to implement at industrial scale to monitor CHO cell cultures.
Spatial Analysis of Wenchuan Earthquake-Damaged Vegetation in the Mountainous Basins and Its Applications
Authors: Zhang Huaizhen , Chi Tianhe , Fan Jianrong , Hu Kaiheng , Peng Ling
Published: May 2015

The 2008 Wenchuan Earthquake induced landslides that destroyed large swaths of mountain vegetation. Presently, the damaged vegetation areas are exhibiting various stages of recovery depending on environments. A spatial analysis of earthquake-damaged and recovered vegetation can provide useful information for understanding landslide processes. The mountainous watersheds of the Minjiang River Upstream, near Yinxiu Town (one of the highest seismic intensity zones during the Wenchuan earthquake) were selected. A DSAL (digital elevation model (DEM), slope, aspect and lithology) spatial zonation method was established to detect natural features of the vegetation survival environments, and damaged and recovered vegetation areas were extracted using the normalized difference vegetation index (NDVI) changes form multi-temporal (2001–2014) Landsat Thematic Mapper/Enhanced Thematic Mapper/Operational Land Imager (TM/ETM/OLI) images. Statistical results show that the vegetation growth was mainly controlled by its survival environments, and vegetation has coupling relations with slope stability. Then, the slope stability model was developed through multivariate analysis of earthquake-damaged vegetation and its controlling factors (i.e., topographic environments and material properties). Application to the Mianyuan River and Subao River basins validated the proposed model, showing that monitoring the vegetation (using the remote sensing images) can be used to assess the slope stability, and model results show what vegetative conditions with its survival environments are susceptible to landslide processes, although the predicted values may be higher than the actual values in the most mountainous basins. Our modeling approach may also be valuable for use in other regions prone to landslide hazards.