bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis on Production of Coal Bed Methane Considering the Change in Permeability of Coal Rock
Authors: Likai Zhu , Youjun Ji , Tianhong Yang , Xiaoyu Li
Published: December 2016

Based on the mechanism of migration of the coal bed methane (CBM), and taking into account the deformation of the coal rock during the process of CBM production was also taken into account, a coupled mathematical model considering the interaction of solid and fluid for methane extraction was built. The coal gas extraction of JINcheng coal mine was taken as an example, some typical coal sample was chosen to test the permeability under different confining pressure. The curve for permeability of coal rock versus effective stress under different confining pressure was obtained, a numerical model considering the variation of permeability for methane extraction was set up. The influence of deformation of coal rock on the gas production was simulated and analyzed. The simulation results indicate that the productivity curve considering deformation of rock is closer to the actual production data, at the initial stage of production, the gas rate is less than the case without considering deformation of rock, but the time of stable yield will last longer, and this matches the actual methane extraction, therefore, we recommend that the deformation of coal seam should be considered during the prediction of methane production for JINcheng coal mine.
Estandarización de un método de detección molecular del Cucumber mosaic virus (cmv) en banano ecuatoriano
Authors: Buitrón-Bustamante Johanna Liseth
Published: December 2016

El cultivo del banano en el Ecuador se ve afectado por una serie de enfermedades, de las cuales el Cucumber mosaic virus (cmv) es uno de los fitopatógenos más importantes. Con este estudio se buscó estandarizar una técnica molecular para la detección sensible y altamente específica de este agente viral en el banano ecuatoriano. Para este fin, se realizó el diseño de primers específicos, a partir de la secuencia que se codifica para la proteína de la cápside del virus. Los primers PC-F1, PC-RD1 y K-F, usados en cDNA replicado a partir de ARN de banano infectado, permitieron detectar eficientemente la presencia del virus con la aplicación de reacciones de retrotranscripción y hemi-nested PCR. Se reportó la detección del virus incluso en plantas asintomáticas, lo cual evidencia que esta técnica resulta de alta sensibilidad para su aplicación en diagnósticos rutinarios del sector bananero.
Biorremediación de organofosforados por hongos y bacterias en suelos agrícolas: revisión sistemática
Authors: Hernández-Ruiz Gina María
Published: December 2016

Los organofosforados son un tipo de plaguicidas ampliamente utilizados en el sector agrícola para el control de plagas. Dado que estos son compuestos químicos altamente tóxicos, su uso excesivo ha causado gran deterioro en los suelos cultivables, así como graves daños para los ecosistemas y la salud humana. La biorremediación surge como una alternativa para transformar los plaguicidas en compuestos más simples y poco contaminantes mediante el uso del potencial metabólico de los microorganismos. Por lo anterior, el objetivo de esta investigación fue describir los hongos y bacterias involucrados en la biorremediación de los principales plaguicidas organofosforados empleados en suelos agrícolas por medio de una revisión sistemática de la literatura científica, con el fin de aportar información útil para la realización de estudios posteriores. Se obtuvo información científica de las bases de datos ScienceDirect y Springer Link, y también información no indexada del buscador Google Scholar. Se encontró que el organofosforado que más se ha estudiado es el clorpirifós (categoría toxicológica III) y los microorganismos que más se utilizan como biorremediadores de organofosforados son los géneros Serratia, Bacillus y Pseudomonas. Se concluye que el éxito de la biorremediación depende de la capacidad competitiva de los microorganismos, de la biodisponibilidad y la concentración del organofosforado, del pH, la temperatura y el tipo de suelo, así como de la presencia de suplementos nutricionales y de la concentración alta del inóculo.
KONSUMSI BERAS ORGANIK PADA TINGKAT RUMAH TANGGA DI KOTA YOGYAKARTA
Authors: Sulistyana Pradesi , Mulyo Jangkung Handoyo , Jamhari Jamhari
Published: December 2016

This research was conducted (1) to determine the organic rice consumption patterns in the region of Yogyakarta City (2) to determine the characteristics of organic rice consumed in the region of Yogyakarta City and (3) to identify the factors influencing the demand for organic rice in Yogyakarta City. The basic method for this research is descriptive analysis. The research located in Yogyakarta City were determined through incidental sampling, there were 35 organic rice consumers as respondents. The data was analyzed by multiple linier regression analysis by Ordinary Least Square (OLS). The result showed that (1) there are 3 categories for the consumption patterns of organic rice at the household level in Yogyakarta City, they are  routinely, mixed, and occasionally, with the following results: total food expenditure per month 2,1 million rupiahs - 5 million rupiahs (45,71%), the amount of consumption per month is 21-40 kg by the number of family 5-7 members (51,43%), most consumers choose distributor as a place to purchase organic rice (60%), the main reason of organic rice consumption is the health factor (88,57%), consumers are satisfied to consume organic rice (85,71%), the long of consumption is 1-6 months (42,86%), source of information about the benefits of organic rice from the electronic media (36,36%) and information about the characteristics of organic rice from distributors, (2) consumers of organic rice at the household in Yogyakarta City (40%) consume organic rice from menthik wangi variety that has typical characteristic of white color, rice color level is clear, the rice smells fragrant, rough texture, low broken rice percentage (10-20%), sweet taste, rice fluffiness level is fluffier and more durable resistance, (3) the consumption of organic rice is positively affected by organic rice consumption are the price of non-organic rice, instant noodles price, health factor and negatively affected by price of tempe and tahu price. Non-organic rice and instant noodles are substitutes for organic rice, while tempe and tahu are complements of organic rice.
FAKTOR-FAKTOR YANG MEMPENGARUHI IMPOR GANDUM INDONESIA
Authors: Pradeksa Yogi , Darwanto Dwidjono Hadi , Masyhuri Masyhuri
Published: December 2016

The purpose of this research are to determine the factors that influence the Indonesian wheat imports and the trend of Indonesian wheat imports. The method used in this research was descriptive analysis method using time series data from the years 1992 to 2011. The variables used are national income (GNP), population, international wheat prices, domestic rice prices, exchange rates, and the use of wheat flour by industry. The trend of import volume of wheat showed that there will be additional of import wheat volume around of 11.793 ton per year. Determinant factors which significantly affecting import volume of wheat are national income (GNP), population, international wheat prices and exchange rates, while the domestic rice prices and the use of wheat flour by industry had no significant effect on the volume of imports.
ANALISIS PENDAPATAN DAN TINGKAT KESEJAHTERAAN RUMAH TANGGA PETANI TEBU TANAM DAN KEPRASAN DI KABUPATEN BANTUL
Authors: Rohmah Wasilatur , Suryantini Any , Hartono Slamet
Published: December 2016

This study aimeds to determine (1) factors affecting sugarcane production (2) factors affecting the sugarcane income (3) the risk ofsugarcane production and income (4) contribution of sugarcane farm-income to farmer households’ income (5) income distribution among farmer households (6) the level of farmer households’ welfare in Bantul District. The basic method of this research was descriptive analytical, sample was chosen  purposively. Number of respondent was 30 sugarcane farmers. Analytical tools were the Cobb-Douglas production function and Unit Output Price (UOP) profit function. The result showed that (1) factors that positively influencing to the sugarcane production were land acreage, sugarcane seedlings, ZA fertilizer, pesticides, cultivating labor, harvesting labor and cropping method (2) factor that positively influencing to the sugarcane income was land acreage. Income factor that had negatively influence to the sugarcane income were sugarcane seedling’s price and cultivating labor’s wage (3) production risk of second ratoon sugarcane  was the highest among other sugarcane planting systems. Income risk of second ratoon sugarcane  was the highest among other sugarcane planting system (4) contribution of sugarcane income to the farm household income was the majority (5) sugarcane income could improve farm household’s income distribution (6) sugarcane farm-households was classified as a prosperous household.
ANALISIS EFISIENSI ALOKATIF FAKTOR-FAKTOR PRODUKSI SORGUM DI KABUPATEN GUNUNGKIDUL
Authors: Arta Sandi Budi , Darwanto Dwidjono Hadi , Irham Irham
Published: December 2016

This research aims to (1) determine the factors that influence the sorghum production in Gunungkidul District; (2) determine theallocative efficiency of sorghum production factors in Gunungkidul District. Number of respondents were 30 farmers chosen by purposive sampling. Analysis tools used in this research were the Cobb-Douglass Production Function and Allocative Efficiency Analysis. The result showed that the inputs such as  land, seeds and organicfertilizerpositive affected to production of sorghum in Gunungkidul District. Result ofAllocative Efficiency analysis showedthat allocation ofland, seeds and organicfertilizer have not been efficient insorghum’sfarming in Gunungkidul District.
MOTIVASI ANGGOTA KELOMPOK WANITA TANI DALAM DIVERSIFIKASI PANGAN LOKAL DI KABUPATEN BANTUL
Authors: Kinasih Resti , Subejo Subejo , Witjaksono Roso
Published: December 2016

This research was done in Bantul district. The purposes of this research were to find out the motivation rate of women farmers group in diversification of local food in Bantul district, the influencing factors, and also to find out the influence of motivation and the other factors to successing local food diversification. This research bassicaly applied analytic descriptive method and used purposive method for sub-district and women farmers group sampling. It was took 15 group members from each women farmers group using simple random sampling, so in total there were 60 members as sample. Data analysis has been done by using propostion test and multiple regression analysis. The research results showed that the larger part of women farmers group in Bantul district have a high motivation on the local food diversification, price of rice and active counseling have a possitive influence on motivation. Meanwhile, age, level of education, income, perception of local foods, and mass media access do not have influence to the motivation of local food diversivication. Price of rice has a negative influence on success local food diversification, while income, active counseling, perception of local foods have a possitive influence of local food diversification sucess. Meanwhile, age, level of education, mass media access and motivation do not have influence on local food diversification success.
MOTIVATION FOR INDIVIDUALS’ INVOLVEMENT WITH FAN PAGES
Authors: Abdillah Willy
Published: December 2016

This research examines the empirical model of individuals’ involvement with fan pages. The research model was developed based on the social influence factors and the brand post popularity model. The research employed an online survey questionnaire. 300 samples were collected by using a purposive sampling technique, and analyzed using the Partial Least Square (PLS) method. The results showed that identification, interactivity, informational content and valence of comment were the motivating factors for the intent to become involved with fan pages. It was indicated that the brand popularity model was not the only relevant model to explain the social computing phenomenon in the context of fan pages, but social influence factors also play a part. The implications for stakeholders and further research are discussed. Keywords: Social influence factors, brand post popularity factors, intention, and involvement with fan pages
Organic Lawn Care Case Studies on Home Turf
Authors: Heckman Joseph R.
Published: December 2016

The consistent growth in certified organic farming and demand for organic foods has fostered a companion movement towards employing organic growing methods for land care. With the objective of evaluating the agronomic potential for organic land care, I conducted a case study on my property in Monroe, NJ following land disturbance from construction. After the site was remediated with deep tillage to alleviate compaction and amended with compost and limestone based on soil tests it was seeded in September 2009 with a mix of modern turf type Kentucky bluegrass cultivars. Once established, this lawn was attractive, competitive against most weeds, and performed well over the following six years under organic management. This lawn was mowed frequently with the clippings always returned so as to recycle nutrients in place. It remained attractive without fertilizer input. In 2014, another organic lawn study was established at my farm in Ringoes, NJ to evaluate several organic fertilizers. Observations from this second case study indicated that soil test P was a key factor for turf establishment. Experience with the organic lawn in Ringoes, when contrasted to the results in Monroe, suggested that rapid germination and establishment of a dense turf stand is very important to preventing weeds during establishment.
Transaction costs and corporate governance of sugar mills in Indonesia
Authors: Yustika Ahmad Erani
Published: December 2016

The sugar industry remains a priority for development in the Indonesian agricultural sector, especially in East Java. However, the performance of the sugar industry in East Java during the two last decades has declined, which is shown in the decreasing volume of production. This study utilized the analysis of transaction cost economics to identify the problems of the sugar mills in East Java – Indonesia. This research compares the transaction costs between state-owned (Ngadiredjo) and privately-owned (Kebon Agung) sugar mills. The study shows that in Kebon Agung Sugar Mill transaction costs are higher than production costs, while in Ngadiredjo Sugar Mill the reverse is true. However, the high transaction costs in Kebon Agung Sugar Mill cannot be attributed directly to inefficient institutions, because Ngadiredjo Sugar Mill incurred high costs for plants, land preparation, and fertilizer, which decreased the proportion of transaction costs. If analyzed in detail, the following facts are revealed: (i) market transaction costs in Kebon Agung Sugar Mill are higher than in Ngadiredjo Sugar Mill. This is because Kebon Agung Sugar Mill has established cooperation with sugarcane farmers in the form of extensions and transport subsidies; and (ii) the political transaction costs proportion in Ngadiredjo Sugar Mill is higher than in Kebon Agung Sugar Mill because of the imposition of many ‘illegal’ fees. There should be management (corporate) reform of sugar mills, both internal and external. Internally, sugar mill management must apply good corporate governance that guarantees the transparency and control of every activity. Nowadays, there is no controlling unit in sugar mill management that supervises corporate activity, so that it is susceptible to manipulation and mark-up. Externally, the relationship between sugar mill management (CEO) and the Board of Directors should be reformulated so that sugar mill management has wide authority to make corporate strategy decisions. Centralization of authority in holding firm (PTPN/PT. RNI) has caused high transaction costs as a result of the long hierarchy in decision-making.
Evolution of ownership and control in Italian IPO firms
Authors: Rigamonti Silvia
Published: December 2016

This article examines the evolution of ownership of cash flow rights and control of voting rights of firms that went public in Italy over the period 1985-2005. At the IPO, the ownership structure does not evolve towards a dispersed one. Even 10 years after the flotation, the initial ultimate shareholder retains the majority of voting rights. Though control is valuable, original owners do not systematically set up structures that dissociate cash flow from voting rights.
The social cost of due care in business judgment
Authors: Jon Woo-Jung
Published: December 2016

This article considers whether it is justifiable to reduce damages where directors are liable for business failure. It argues that holding directors liable for all damage due to business failure prevents individual directors from doing business enterprisingly. According to a cost-benefit analysis, the fear of potential liability results in excessive costs when business decisions are made. The total costs that individual directors expend in making business decisions is smaller than the total costs of the company as the company’s costs includes not only directors’ costs but also other employees’ costs. In comparison, the total amount of loss that individual directors may suffer due to a business failure is far larger than the total loss of the company, where the directors are liable for the total loss of the company jointly and severally. It is because the directors would also suffer salary reduction or discharge. Under these circumstances, the directors should pay close attention in order not to err in their business judgment. Thus, even where risks are minimal, directors may act too cautiously and passively, rather than pursue a more profitable entrepreneurship aggressively. Therefore, the simple compensatory principle may not be adequate where business failure occurs
Control and risk of CEO compensation.
Authors: Álvarez-Pérez María Dolores , Neira Fontela Edelmira , Castro Casal Carmen
Published: December 2016

This study analyses the influence of various characteristics of the Board of Directors on the control and risk of the compensation of the Chief Executive Officer (CEO). It also examines the effect on these variables of some of the CEO personal characteristics and of various contingencies of the firm. The results reveal that control of the CEO compensation is determined fundamentally by the CEO participation in the capital of the firm, while the level of risk of the CEO compensation package is higher when the firm is diversified and implements a proactive competitive strategy.
Measuring corporate governance in Germany: An integrated framework on compliance and transparency & disclosure
Authors: Graf Andrea , Stiglbauer Markus
Published: December 2016

Compliance as well as transparency and voluntary corporate disclosure are essential within the concept of ´good` corporate governance. Consequently, there is an increasing demand for methods enabling investors to compare companies by means of country-specific criteria. However, measures in Germany do not provide a broad spectrum of criteria for evaluating corporate compliance and governance transparency & disclosure. Our framework covers all rules of the German Corporate Governance Code as well as additional criteria, enabling investors to analyse how companies are managed. Furthermore, we raise quality criteria of social sciences to confirm our findings.
Two faces of busy outside directors
Authors: Chen Chia-Wei , Lin Jang-Shee Barry , Yi Bingsheng
Published: December 2016

In this study, we examine how multiple directorships held by outside directors (busy outside directors) influence shareholder wealth in diversifying acquisitions. With a sample of 893 diversifying acquisitions from 1998 to 2004, we find a negative (positive) busy-director effect for diversifying acquisitions of public-targets (private-targets). Busy directors are negatively (positively) associated with the five-day cumulative abnormal returns in acquisitions involving public (private) targets, where merger-related agency problems are more likely. Our evidence support the notion that, in the case of diversifying acquisitions, increased managerial monitoring plays a more important role versus enhanced advising and business connection from busy directors.
Strategic orientation and corporate governance: The role of ownership
Authors: Di Toma Paolo
Published: December 2016

Challenging universal perspectives that directed previous mainstream research, this theoretical paper addresses the potential influence of contextual variables on corporate governance. The main purpose is to contribute to the development of recent perspectives investigating the corporate governance effectiveness in terms of fitting into the firm’s strategic orientation. This paper points out how different arrangements may support the enterprise or the accountability function and how differently they work, according to their specific context. Potential influences stemming from ownership structure are then considered, addressing relationships between the firm’s strategic dynamics and corporate governance effectiveness. Understanding the association between the strategic orientation and corporate governance functions and their consistent changes along the firm’s life cycle is a useful premise to a dynamic view of corporate governance effectiveness and its contribution to value creation.
Corporate governance and firm value: Evidence from Canadian capital markets
Authors: Gupta Parveen , Kennedy Duane , Weaver Samuel
Published: December 2016

The Globe and Mail’s Report on Business annually publishes governance rankings for more than 200 companies represented in the TSX/S&P index. There are four sub-categories that comprise the composite scores: board composition; board and CEO compensation; shareholder rights; and board governance disclosure. The purpose of this paper is to examine the association between the composite or sub-category corporate governance scores and various measures of firm value. We test for this association using data for 2002 through 2005 on the Report on Business rankings and various financial and market measures. Overall, our study does not find an association between the composite or subcategory corporate governance scores and the various measures of firm value.
The governance structure of Portuguese and Spanish credit cooperatives: Differences and similarities
Authors: Cabo Paula , Melian-Navarro Amparo , Rebelo João
Published: December 2016

The literature recognizes that credit cooperatives are the “appropriate technology” for relatively backward economies, but should fade away or disappear altogether as economic development proceeds. However, surprisingly, they are among the fastest growing groups of financial institutions in some advanced economies. Though the credit cooperatives in Portugal and Spain present relatively small market shares, they perform a very important role in the rural economy. Over the last decades, the Iberian credit cooperatives have adopted a process of economic and financial restructuring, through an intensive wave of mergers and the creation of banking networks: Caja Rural Group, in Spain, and Crédito Agrícola Group, in Portugal. Despite that common path, the Iberian reality is still very different. In this paper we describe the historical roots of Portuguese and Spanish cooperative credit, focusing our analysis on the governance structure, especially on the issues arising from the strict application of traditional cooperative rules.
Bad debts, ownership concentration, and board composition: evidence on the quality of corporate governance outcomes in China’s listed non financial companies
Authors: Shan Yuan George , McIver Ron P.
Published: December 2016

This study analyses the relationships between performance metrics and the corporate control and governance characteristics of a sample of China’s listed non-financial companies in order to assess the influence of corporate governance structures on the quality and independence of corporate decision making. We use a panel data set covering the years 2001 to 2005 comprised of a stratified sample of A, AB and AH non-financial companies listed on China’s Shanghai and Shenzhen stock exchanges. We find that concentration of ownership, including state and foreign ownership, and board size and independence are significant factors in determining performance outcomes, and by association the quality and independence of corporate policy decisions, as measured in the form of firm bad debt to total asset and bad debt to receivables ratios. Our findings support claims of continued inadequacies in the operation and effectiveness of China’s institutions of corporate governance, especially with respect to the effectiveness of the supervisory board.
Do portfolio managers in South Africa consider human behaviour issues when making investment decisions or advising clients?
Authors: Strydom JSG , Van Rooyen JH
Published: December 2016

The efficient market hypothesis is based on the assumption that individuals act rationally, processing all available information in their decision-making process. Prices therefore reflect the appropriate risk and return. However, research conducted regarding the ways that investors arrive at decisions when faced with uncertainty, has revealed that this is in fact not always the case. People often make systematic errors, the so-called cognitive biases, which lead them to less rational behavior than the traditional economic paradigm predicts. These cognitive biases have been found to be responsible for various irregular phenomena often observed in financial markets as (turbulence or, volatility, seasonable cycles, "bubbles", etc. Behavioral finance attempts to explain some of the changes in the financial markets that cannot be explained by the efficient market hypothesis. This research reviews some results from the behavioral finance and other related literature. A survey was also done to determine whether the most prominent portfolio managers in South Africa are aware of behavioral finance issues/models and consider the influence of cognitive issues when making investment decisions or giving advice to clients.
The corporate social responsibility manager map
Authors: Molteni Mario , Pedrini Matteo
Published: December 2016

This article outlines the profile of ninety managers directly involved in Corporate Social Responsibility activities (CSR Managers) in Italian firms. It presents an analysis of the organizational position, educational background and activities of these professionals. The results suggest that CSR managers: 1) have a growing relevance in the firm; 2) are predominantly existing members of the organization; 3) have principally a business management educational background; 4) play a key role in supporting senior management and improving stakeholder engagement. It emerges that CSR managers are supporting senior management in different manners. The “CSR Manager Map” allows for the identification of four types of CSR manager: (1) Specialist; (2) Generalist; (3) Process oriented; (4) External oriented.
Impact of index derivatives on Indian stock market volatility-an application of arch and GARCH model
Authors: Ramana Rao S. V. , Tripathy Naliniprava
Published: December 2016

The present study examined the impact of introduction of index futures derivative and index option derivative on Indian stock market by using ARCH and GARCH model to capture the time varying nature of volatility presence in the data period from October 1995 to July 2006. The results reported that the introduction of index futures and index options on the Nifty has produced no structural changes in the conditional volatility of Nifty but however the market efficiency has been improved after the introduction of the derivative products. The study concludes that financial derivative products are not responsible for increase or decrease in spot market volatility, but there could be other market factors which influenced the market volatility
Effects of human resource practices on family firms social performance
Authors: Colot Olivier , Dupont Claire , Volral Mélanie
Published: December 2016

The aim of our research is to analyse social performance (through turnover rate) of large family owned business in relation to their human resource practices. We made multiple regressions on a sample of 60 large firms. Our global model, considering large family owned business and non-family owned business, shows that part-time contracts increase turnover significantly, while training reduces it. We observe the same relation when we analyse family owned business specifically where we also note that to belong to the trade sector influences turnover significantly. When we consider non-family owned business on the other hand, then variables like pay, training, firm’s age and services or building sectors tend to affect turnover significantly.
PERSINGGUNGAN ISLAM DAN TRADISI MISTIK LOKAL: STUDI KASUS PANANYAAN DAN AHLI HIKMAH DI MASYARAKAT TASIKMALAYA
Authors: Musadad Asep Nahrul
Published: December 2016

AbstrakOne of the determinant factors in the process of Islamization of the archipelago is the intersection between Islamic teachings and local wisdom. The encounter of the two has apparently brought an esoteric way. In this case, the Islamic esoteric teaching namely Sufism has become important. However, there was another esoteric element which also has a main role in the process, namely the mystical insight as to the result of the synthesis of the Islamic esoteric teaching and the indigenous mystical tradition. Using the ethnographic approach, this article aims to provide a preliminary remark on the intersection between Islam and local mystic tradition as represented by “pananyaan” and “ahli hikmah” in Sundanese people, especially in Tasikmalaya, as the reference. He is regarded as the “learned man” a place for someone to ask, especially related to the world of unseen.
Mixed convection boundary-layer flow of a viscoelastic fluid due to horizontal elliptic cylinder with constant heat flux
Authors: Javed Tariq , Ahmad Hussain , Ghaffari Abuzar
Published: December 2016

This article presents numerical analysis of mixed convection laminar flow of a second grade viscoelastic fluid due to cylinder of elliptic cross-section with prescribed surface heat flux. Dimensionless non-linear analysis is computed employing Keller-box method. Skin friction coefficient and Nusselt number are emphasized specifically. These quantities are displayed graphically to examine their behavior along the surface of cylinder. The flow and heat transfer rates are carefully judged while varying the important resulting parameters (mixed convection parameter, viscoelastic parameter aspect ratio, etc.) through sketched graphs keeping major axis of ellipse along and perpendicular to the horizontal. These two positions of major axis are termed as blunt and slender orientations, respectively. The values of skin friction and Nusselt number increase with rise in mixed convection parameter. On the other hand, these quantities lessen by increasing the value of viscoelastic parameter.
Review of the research on the turbulence in the laboratory for thermal engineering and energy
Authors: Cvetinovic Dejan , Stefanovic Predrag , Bakic Vukman , Oka Simeon
Published: December 2016

Paper gives a review of the most important results of turbulence research
achieved by the Laboratory for Thermal Engineering and Energy. Paper
presents detailed overview of the history of the scientific research
provided in the laboratory, from the beginning in the mid-60s to today,
pointing out the main reasons initiating the investigations in this field.
After the first period, which was mainly devoted to the research of the
structure of the turbulence, since the beginning of the 80s, research is
mainly oriented to the flows at high temperatures including chemical
reactions and to the development and improvement of differential
mathematical models as a modern and very efficient tool in the technological
development. This research significantly contributed to the development of
pulverized coal burners, plasma-chemical reactors, and optimization of
pulverized coal fired boilers operating parameters and prediction of the
greenhouse gases emissions. Most recent period includes experimental and
numerical studies of the coherent structures in turbulent fluid jets,
mathematical modeling of various turbulent thermal flow processes including
two-phase turbulent flow in the multiphase heat exchangers and mathematical
modeling of the atmospheric boundary layer.
The processes of vaporization in the porous structures working with the excess of liquid
Authors: Genbach Alexander , Jamankulova Nellya , Bakic Vukman
Published: December 2016

The processes of vaporization in porous structures, working with the excess
of liquid are investigated. With regard to the thermal power plants new
porous cooling system is proposed and investigated, in which the supply of
coolant is conducted by the combined action of gravity and capillary forces.
The cooling surface is made of stainless steel, brass, copper, bronze,
nickel, alundum and glass, with wall thickness of (0.05-2)?10-3 m.
Visualizations of the processes of vaporization were carried out using
holographic interferometry with the laser system and high speed camera. The
operating conditions of the experiments were: water pressures (0.01-10) MPa,
the temperature difference of sub-cooling (0-20)?C, an excess of liquid
(1-14) of the steam flow, the heat load (1-60)?104 W/m2, the temperature
difference (1-60)?C and orientation of the system (? 0 - ? 90) degrees.
Studies have revealed three areas of liquid vaporization process
(transitional, developed and crisis). The impact of operating and design
parameters on the integrated and thermal hydraulic characteristics was
defined. The optimum (minimum) flow rate of cooling fluid and the most
effective type of mesh porous structure were also defined.
Numerical aerodynamic-thermal-structural analyses of missile fin configuration during supersonic flight conditions
Authors: Ognjanovic Ognjen , Maksimovic Stevan , Vidanovic Nenad , Segan Stevo , Kastratovic Gordana
Published: December 2016

Attention in this work is focused on aerodynamic heating and
aero-thermo-mechanical analysis of fin type structures on the missile at
supersonic flight. At high Mach number the heat due to friction between body
and flow, i.e. viscous heating must be taken into account because the
velocity field is coupled with the temperature field. The flow field around
the fins of the missile and especially the temperature distribution on its
surface, as well as aerodynamic-thermal-structural analyses are numerically
modeled in ANSYS Workbench environment. The investigation was carried out
for two Mach numbers (M = 2.3 and M = 3.7). Own available structural
experimental results have been used for computational structural mechanics
(CSM) validation and verification, in order to assure credibility of
numerical fluid-thermal-structure interaction (FTSI). Conducted simulations
were carried out to better understand the FTSIs of the missile fin during
supersonic flight.
Exact traveling-wave solutions for linear and nonlinear heat-transfer equations
Authors: Gao Feng , Yang Xiao-Jun , Srivastava Hari
Published: December 2016

The exact traveling-wave solutions for the linear and non-linear heat transfer equations at several different excess temperatures are addressed and investigated in this paper.
An experimental assessment on the influence of high octane fuels on biofuel based dual fuel engine performance, emission, and combustion
Authors: Masimalai Senthilkumar , Subramanian Arulselvan
Published: December 2016

This paper presents an experimental study on the effect of different high octane fuels (such as eucalyptus oil, ethanol, and methanol) on engine?s performance behaviour of a biofuel based dual fuel engine. A single cylinder Diesel engine was modified and tested under dual fuel mode of operation. Initially the engine was run using neat diesel, neat mahua oil as fuels. In the second phase, the engine was operated in dual fuel mode by using a specially designed variable jet carburettor to supply the high octane fuels. Engine trials were made at 100% and 40% loads (power outputs) with varying amounts of high octane fuels up-to the maximum possible limit. The performance and emission characteristics of the engine were obtained and analysed. Results indicated significant improvement in brake thermal efficiency simultaneous reduction in smoke and NO emissions in dual fuel operation with all the inducted fuels. At 100% load the brake thermal efficiency increased from 25.6% to a maximum of 32.3, 30.5, and 28.4%, respectively, with eucalyptus oil, ethanol, and methanol as primary fuels. Smoke was reduced drastically from 78% with neat mahua oil a minimum of 41, 48, and 53%, respectively, with eucalyptus oil, ethanol, and methanol at the maximum efficiency point. The optimal energy share for the best engine behaviour was found to be 44.6, 27.3, and 23.2%, respectively, for eucalyptus oil, ethanol, and methanol at 100% load. Among the primary fuels tested, eucalyptus oil showed the maximum brake thermal efficiency, minimum smoke and NO emissions and maximum energy replacement for the optimal operation of the engine.
Treatment of unresectable skull base meningiomas with somatostatin analogs
Authors: Schulz Chris , Mathieu René , Kunz Ulrich , Mauer Uwe Max
Published: December 2016

Object

The standard surgical treatment for meningiomas is total resection, but the complete removal of skull base meningiomas can be difficult for several reasons. Thus, the management of certain meningiomas of the skull base—for example, those involving basal vessels and cranial nerves—remains a challenge. In recent reports it has been suggested that somatostatin (SST) administration can cause growth inhibition of unresectable and recurrent meningiomas. The application of SST and its analogs is not routinely integrated into standard treatment strategies for meningiomas, and clinical studies proving growth-inhibiting effects do not exist. The authors report on their experience using octreotide in patients with recurrent or unresectable meningiomas of the skull base.

Methods

Between January 1996 and December 2010, 13 patients harboring a progressive residual meningioma (as indicated by MR imaging criteria) following operative therapy were treated with a monthly injection of the SST analog octreotide (Sandostatin LAR [long-acting repeatable] 30 mg, Novartis). Eight of 13 patients had a meningioma of the skull base and were analyzed in the present study. Postoperative tumor enlargement was documented in all patients on MR images obtained before the initiation of SST therapy. All tumors were benign. No patient received radiation or chemotherapy before treatment with SST. The growth of residual tumor was monitored by MR imaging every 12 months.

Results

Three of the 8 patients had undergone surgical treatment once; 3, 2 times; and 2, 3 times. The mean time after the last meningioma operation (before starting SST treatment) and tumor enlargement as indicated by MR imaging criteria was 24 months. A total of 643 monthly cycles of Sandostatin LAR were administered. Five of the 8 patients were on SST continuously and stabilized disease was documented on MR images obtained in these patients during treatment (median 115 months, range 48–180 months). Three of the 8 patients interrupted treatment: after 60 months in 1 case because of tumor progression, after 36 months in 1 case because of side effects, and after 36 months in 1 case because the health insurance company denied cost absorption.

Conclusions

Although no case of tumor regression was detected on MR imaging, the study results indicated that SST analogs can arrest the progression of unresectable or recurrent benign meningiomas of the skull base in some patients. It remains to be determined whether a controlled prospective clinical trial would be useful.
The molecular genetics and tumor pathogenesis of meningiomas and the future directions of meningioma treatments
Authors: Choy Winward , Kim Won , Nagasawa Daniel , Stramotas Stephanie , Yew Andrew , Gopen Quinton , Parsa Andrew T. , Yang Isaac
Published: December 2016

Meningiomas are mostly benign, slow-growing tumors of the CNS that originate from arachnoidal cap cells. While monosomy 22 is the most frequent genetic abnormality found in meningiomas, a multitude of other aberrant chromosomal alterations, signaling pathways, and growth factors have been implicated in its pathogenesis. Losses on 22q12.2, a region encoding the tumor suppressor gene merlin, represent the most common genetic alterations in early meningioma formation. Malignant meningioma progression, however, is associated with more complex karyotypes and greater genetic instability. Cytogenetic studies of atypical and anaplastic meningiomas revealed gains and losses on chromosomes 9, 10, 14, and 18, with amplifications on chromosome 17. However, the specific gene targets in a majority of these chromosomal abnormalities remain elusive.

Studies have also implicated a myriad of aberrant signaling pathways involved with meningioma tumorigenesis, including those involved with proliferation, angiogenesis, and autocrine loops. Understanding these disrupted pathways will aid in deciphering the relationship between various genetic changes and their downstream effects on meningioma pathogenesis.

Despite advancements in our understanding of meningioma pathogenesis, the conventional treatments, including surgery, radiotherapy, and stereotactic radiosurgery, have remained largely stagnant. Surgery and radiation therapy are curative in the majority of lesions, yet treatment remains challenging for meningiomas that are recurrent, aggressive, or refractory to conventional treatments. Future therapies will include combinations of targeted molecular agents as a result of continued progress in the understanding of genetic and biological changes associated with meningiomas.
Meningiomas involving the optic canal: pattern of involvement and implications for surgical technique
Authors: Taha Ahmed Nageeb M. , Erkmen Kadir , Dunn Ian F. , Pravdenkova Svetlana , Al-Mefty Ossama
Published: December 2016

Object

Juxtasellar meningiomas frequently extend into the optic canal. Removing these meningiomas from the optic canal is crucial for favorable visual outcome.

Methods

The authors performed a retrospective analysis of 45 patients with anterior and middle fossa meningiomas with involvement of the optic pathway in whom surgery was performed by the senior author (O.A.M.) during the period from 1993 to 2007. Extent of resection and recurrence rates were determined by pre- and postoperative MR imaging studies. Visual outcomes were evaluated with full ophthalmological examinations performed before and after surgery.

Results

Forty-five patients (31 women and 14 men) were involved in this study; their mean age was 51.6 years. Patients were followed for a mean of 29.8 months (range 6–108 months). No surgery-related death occurred. The average tumor size was 3.1 cm. Total resection of the tumor (Simpson Grade I) was achieved in 32 patients (71.1%). Gross-total resection (Simpson Grades II and III) was achieved in 13 patients (28.9%). Only 1 patient harboring a left cavernous sinus meningioma had tumor recurrence and underwent repeat resection. Meningiomas extended into 58 optic canals in these cases; 13 patients showed extension into both optic canals. Visual disturbance was the main presenting symptom in 37 patients (82.2%); 8 patients had normal vision initially. Visual improvement after surgery was seen in 21 (57%) of 37 patients and in 27 (34.6%) of 78 affected eyes. Vision remained unchanged in 48 (61.5%) of 78 eyes. Transient postoperative visual deterioration occurred in 2 eyes (2.6%), with recovery to baseline over time. Only 1 (1.3%) of 78 eyes had permanent visual deterioration after surgery. The visual outcome was affected mainly by the tumor size, the preoperative visual status, and the duration of symptoms.

Conclusions

Involvement of the optic canal in meningiomas is frequent. It occurs in a wide variety of anterior skull base meningiomas and it can be bilateral. It is a prominent factor that affects the preoperative visual status and postoperative recovery. Decompression of the optic canal and removal of the tumor inside is a crucial step in the surgical management of these tumors to optimize visual recovery and prevent tumor recurrence.
Neurosurgical management of extraaxial central nervous system infections in children
Authors: Gupta Sanjay , Vachhrajani Shobhan , Kulkarni Abhaya V. , Taylor Michael D. , Dirks Peter , Drake James M. , Rutka James T.
Published: December 2016

Object

Extraaxial infections of the CNS, including subdural empyema and epidural abscess, are rare but potentially life-threatening conditions. Symptoms are usually progressive, and early diagnosis is therefore important. Early intervention with appropriate treatment offers the best opportunity for eradicating the infection and promoting maximal neurological recovery.

Methods

The medical records of children with extraaxial CNS infection over the last 24 years at the Hospital for Sick Children were analyzed. Only those patients with radiological and/or operative confirmation of the diagnosis of subdural empyema or epidural abscess were included in the study. Demographic and clinical data were collected to determine the outcomes after such infections and factors that predict for such outcomes.

Results

The authors identified 70 children who fulfilled the inclusion criteria. Sinusitis was the most common etiology and was seen in 38 patients. All of these patients were older than 7 years of age at diagnosis. Subdural empyemas were diagnosed in 13 patients following bacterial meningitis, and they were found primarily in infants within the 1st year of life. Other etiological factors included otogenic infection (4 cases), postneurosurgical infection (7 cases), and hematogenous spread of infection (7 cases including 6 cases of spinal epidural abscess). Streptococcus anginosus and Staphylococcus aureus were the most common pathogens identified. Sixty-four patients (91.4%) underwent at least 1 neurosurgical procedure. Seizures and cerebral edema from cortical vein thrombosis were the most common complications.

Conclusions

Due to variable etiology, identification of the responsible microorganism through neurosurgical drainage followed by long-term intravenous antibiotics remains the mainstay in treating extraaxial CNS infections. Optimal outcome is achieved with early diagnosis and therapy.