bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling decomposition of MSW using genetic algorithms
Authors: Reichel T. , Haarstrick A.
Published: October 2008

This paper arose in response to the challenge to landfill modellers developed by the waste management research group of the school of civil and environmental engineering of the University of Southampton (WMRG). Data on the setup and operational procedures of the experiment were provided to modellers; the aim was to make predictions over time of different topics. The model POSE (parametric optimization and simulation of emission) was used to accomplish the task. This model is focused on local reaction processes governed by environmental factors in wastes to predict gas production and evolution of leachate chemistry. The paper provides an overview of the modelling approach and explains the basics of genetic algorithms used in the model. The use and modelling of input data are described and the obtained simulation results are presented. Based on this, predictions of gas formation and leachate chemistry evolution are shown. A comparison of the predicted and monitored data was performed by WMRG and is reported elsewhere.
The long-term settlement of landfill waste
Authors: Ivanova L. K. , Richards D. J. , Smallman D. J.
Published: October 2008

The biodegradation of solid waste materials, the main cause of secondary settlement in landfills, has a significant impact on the post-closure performance of landfill capping systems. Excessive settlement may in turn lead to water ingress and enhanced leachate generation, significantly increasing the risk of harm to the environment. Large-scale long-term laboratory experiments were conducted to identify the rate and magnitude of waste settlement using three purpose-designed test reactors (consolidating anaerobic reactors (CARs)). This paper presents a detailed characterisation of the waste, its associated chemical and physical properties, and the overall volume changes associated with degradation over time. The total magnitudes of settlement after 919 days were 27·6% in CAR 1 (under 150 kPa pressure) and 25·0% in CAR 2 (50 kPa). Long-term secondary settlement was found to be dependent on waste depth—that is, stress dependent. Increased stress (150 kPa) led to a 20% increase in the rates of long-term secondary compression in comparison with a stress level of 50 kPa. Secondary settlement due to biodegradation was found to be of comparable magnitude to the component of secondary settlement caused by mechanical creep (values of 11·1–13·7%). If the settlement behaviour in the CARs approximates to full-scale observations, this data set could be used for validation of quantitative landfill settlement models.
Simulation of municipal solid waste reactors using Moduelo
Authors: Lobo A. , López A. , Cobo N. , Tejero I.
Published: October 2008

The biodegradation and settlement of two consolidating municipal solid waste (MSW) anaerobic reactors operated at Southampton University, UK, were modelled with the Moduelo landfill simulation tool. This paper presents the fundamental concepts of the model, the difficulties found in its application to the studied case and the simulation results obtained. The significant difference found between the rates of anaerobic processes that took place in the field in relation to those in the laboratory required the reduction of the default simulation time step of the model and the introduction of a new parameter to represent the delay in the onset of methanogenesis so that it became predominant after rapid hydrolysis was experienced. Once calibrated by fitting the evolution of the organic content of the leachate during the start-up period (the first 77 days), the model was used to predict leachate concentration, gas generation and composition and settlement of the waste mass throughout the experimental period (919 days). The predicted results will be compared with actual data and discussed in another paper. The exercise here constitutes a basis for reflection on the model's structure and applicability, and serves as a reminder of the difficulty of representing field (landfill) conditions in a laboratory.
A new quality assurance system for the evaluation of ecotoxicity studies submitted under the new substances notification regulations in Canada
Authors: Breton Roger L , Gilron Guy , Thompson Ryan , Rodney Sara , Teed Scott
Published: October 2008

New substances destined for import into, or manufacture in, Canada must be reported to Environment Canada and Health Canada under the New Substances Notification Regulations (Chemicals and Polymers) (NSNR). With the use of information provided by the notifier, and other complementary information available to the 2 departments, the New Substances Program conducts ecological and human health risk assessments. Over the past 10 y, more than 750 ecotoxicity studies have been submitted to the New Substances Program of Environment Canada under the NSNR. Most of these experimental studies are not publicly available but are useful in the ecological risk assessment of new substances and for the development of Quantitative Structure–Activity Relationships (QSARs). In this paper, we describe the development and validation of a computer-based scoring system and our approach in the development of scoring methods used to assess the quality and usability of ecotoxicity studies with fish, Daphnia spp., and green algae. Results of ranking exercises conducted with these methods are described and discussed, together with the potential use of these results in a regulatory context. In addition, the methods are discussed in comparison with other similar evaluation schemes described in the literature.
Exposure modeling on a river basin scale in support of risk assessment for chemicals in european river basins
Authors: van Gils Jos , van Hattum Bert , Westrich Bernhard
Published: October 2008

Following the 2000 European Water Framework Directive and recent insights into sediment management on a river basin scale, we discuss in this paper an exposure model aiming to support a risk assessment for chemicals on a basin-wide scale. It establishes spatial relations between causes (pollution sources) and effects (ecological risk), taking into account the geometry, hydrology, and fine sediment dynamics of European river basins. The model, called EXPOBASIN, explicitly takes into account the interaction of chemicals with fine sediment particles, which is important for many policy-relevant chemicals, such as trace metals and polycyclic aromatic hydrocarbons, and it addresses the potential release of historically polluted sediments as a result of extreme floods, which is a major concern in different European river basins. Bioavailability and bioaccumulation are included in the assessment. As a result, the exposure can be quantified not only in terms of water concentrations, but also in terms of sediment concentrations and concentrations in biota. The primary question to be answered by EXPOBASIN is how chemicals, pollution sources, or both rank quantitatively and objectively on a basin-wide scale. Near the end of 2009, the tool will become available to all European water managers and their technical advisors, as a result of the European Union 6th Framework Programme project MODELKEY The calibration and validation of EXPOBASIN has only just started and will be completed in 2008/2009. Applications to 3 case study areas are planned in this respect. This paper presents the key building blocks of EXPOBASIN and shows some sample results illustrating the raking of pollution sources and chemicals. At the end of the paper, some perspectives for future developments are outlined.
More than Meets the Eye: Social, Economic, and Emotional Impacts of Work-Related Injury and Illness
Authors: Lax Michael B. , Klein Rosemary
Published: October 2008

The impact of an occupational illness or injury on an injured worker can be severe. This study assessed several dimensions of the impact on a group of 50 injured workers, all patients at an Occupational Health Center. The dimensions assessed included aspects of access to health care, support from treating physicians in obtaining Workers' Compensation benefits, financial impacts, the role of attorneys and “Independent Medical Examiners,” and the impact on mental health. The results showed almost two-thirds of respondents lost their health insurance after diagnosis with a work-related illness or injury, most for more than a year. Many reported that their treating physician did not want to become involved in Workers' Compensation, despite indicating a belief that the health condition was work-related. The financial impacts of a work-related diagnosis were particularly striking, with respondents reporting that they were burdened with both costs directly related to the medical care of their condition, and with coping with ongoing general expenses on a reduced income. Many respondents reported depleting savings, borrowing money, taking out retirement funds, and declaring bankruptcy in efforts to cope. Emotionally, respondents almost universally reported their diagnosis and related issues were associated with depression, anxiety, and loss of identity and self-worth. This study demonstrates how a work-related injury or illness can extend far beyond the physical impact for injured workers. Existing systems fail to adequately compensate or rehabilitate injured workers, leaving them to their own devices to deal with their losses, medical or otherwise.
The Reality of SCHIP and Uninsureds: Do SCHIP Mandatory Wait Periods Increase the Uninsured Rolls?
Authors: Nichols Donald , Plotzke Michael
Published: October 2008

Due to the low risk of not insuring a healthy child for a short, finite period of time, it's plausible that SCHIP mandatory wait periods, where a child must forgo private insurance for several months before enrolling in SCHIP, do not provide enough incentive for parents to keep their children enrolled in private insurance. Using data from the 1996 Survey of Income and Program Participation (SIPP), we find that children eligible for SCHIP in states with shorter mandatory wait periods are more likely to be uninsured during the six months following the implementation of SCHIP than children in states with no mandatory wait periods. These children also have lower preventative care utilization, but there is no difference in their acute care utilization or health after one year.
Principal-Agent Problems with Exit Options
Authors: Cvitanic Jaksa , Wan Xuhu , Zhang Jianfeng
Published: October 2008

We consider the problem of when to deliver the contract payoff, in a continuous-time principal-agent setting, in which the agent's effort is unobservable. The principal can design contracts of a simple form that induce the agent to ask for the payoff at the time of the principal's choosing. The optimal time of payment depends on the agent's and the principal's outside options. We develop a theory for general utility functions, while with CARA utilities we are able to specify conditions under which the optimal payment time is not random. However, in general, the optimal payment time is typically random. One illustrative application is the case when the agent can be fired, after having been paid a severance payment, and then replaced by another agent. The methodology we use is the stochastic maximum principle and its link to Forward-Backward Stochastic Differential Equations.
Blow-up of solutions for a viscoelastic equation with nonlinear damping
Authors: Zhifeng Yang
Published: October 2008

The initial boundary value problem for a viscoelastic equation with nonlinear damping in a bounded domain is considered. By modifying the method, which is put forward by Li, Tasi and Vitillaro, we sententiously proved that, under certain conditions, any solution blows up in finite time. The estimates of the life-span of solutions are also given. We generalize some earlier results concerning this equation.
Behavioral Systems Theory: A Survey
Authors: Zerz Eva
Published: October 2008

Behavioral Systems Theory: A Survey

We survey the so-called behavioral approach to systems and control theory, which was founded by J. C. Willems and his school. The central idea of behavioral systems theory is to put the focus on the set of trajectories of a dynamical system rather than on a specific set of equations modelling the underlying phenomenon. Moreover, all signal components are treated on an equal footing at first, and their partition into inputs and outputs is derived from the system law, in a way that admits several valid cause-effect interpretations, in general.
Iterative Learning Control — Monotonicity and Optimization
Authors: Owens David , Daley Steve
Published: October 2008

Iterative Learning Control — Monotonicity and Optimization

The area if Iterative Learning Control (ILC) has great potential for applications to systems with a naturally repetitive action where the transfer of data from repetition (trial or iteration) can lead to substantial improvements in tracking performance. There are several serious issues arising from the "2D" structure of ILC and a number of new problems requiring new ways of thinking and design. This paper introduces some of these issues from the point of view of the research group at Sheffield University and concentrates on linear systems and the potential for the use of optimization methods and switching strategies to achieve effective control.
Mobile Sensor Routing for Parameter Estimation of Distributed Systems Using the Parallel Tunneling Method
Authors: Zięba Tomasz , Uciński Dariusz
Published: October 2008

Mobile Sensor Routing for Parameter Estimation of Distributed Systems Using the Parallel Tunneling Method

The paper deals with the problem of optimal path planning for a sensor network with mutliple mobile nodes, whose measurements are supposed to be primarily used to estimate unknown parameters of a system modelled by a partial differential equation. The adopted framework permits to consider two- or three-dimensional spatial domains and correlated observations. Since the aim is to maximize the accuracy of the estimates, a general functional defined on the relevant Fisher information matrix is used as the design criterion. Central to the approach is the parameterization of the sensor trajectories based on cubic B-splines. The resulting finite-dimensional global optimization problem is then solved using a parallel version of the tunneling algorithm. A numerical example is included to clearly demonstrate the idea presented in the paper.
Application of Triple Correlation and Bispectrum for Interference Immunity Improvement in Telecommunications Systems
Authors: Molchanov Pavel , Totsky Alexandr
Published: October 2008

Application of Triple Correlation and Bispectrum for Interference Immunity Improvement in Telecommunications Systems

This paper presents a new noise immunity encoding/decoding technique by using the features of triple correlation and bispectrum widely employed in digital signal processing systems operating in noise environments. The triple correlation-and bispectrum-based encoding/decoding algorithm is tested for a digital radio telecommunications binary frequency shift keying system. The errorless decoding probability was analyzed by means of computer simulation for the transmission and reception of a test message in a radio channel disturbed by both additive white Gaussian noise (AWGN) and a mixture of an AWGN and an impulsive noise. Computer simulation results obtained for varying and less than unity signal-to-noise ratios at the demodulator input demonstrate a considerable improvement in the noise immunity of the technique suggested in comparison with the traditional redundant linear block encoding/decoding technique.
Immunotherapy with Interleukin-2: A Study Based on Mathematical Modeling
Authors: Banerjee Sandip
Published: October 2008

Immunotherapy with Interleukin-2: A Study Based on Mathematical Modeling

The role of interleukin-2 (IL-2) in tumor dynamics is illustrated through mathematical modeling, using delay differential equations with a discrete time delay (a modified version of the Kirshner-Panetta model). Theoretical analysis gives an expression for the discrete time delay and the length of the time delay to preserve stability. Numerical analysis shows that interleukin-2 alone can cause the tumor cell population to regress.
Emotion Learning: Solving a Shortest Path Problem in an Arbitrary Deterministic Environment in Linear Time with an Emotional Agent
Authors: Petruseva Silvana
Published: October 2008

Emotion Learning: Solving a Shortest Path Problem in an Arbitrary Deterministic Environment in Linear Time with an Emotional Agent

The paper presents an algorithm which solves the shortest path problem in an arbitrary deterministic environment withnstates with an emotional agent in linear time. The algorithm originates from an algorithm which in exponential time solves the same problem, and the agent architecture used for solving the problem is an NN-CAA architecture (neural network crossbar adaptive array). By implementing emotion learning, the linear time algorithm is obtained and the agent architecture is modified. The complexity of the algorithm without operations for initiation in general does not depend on the number of statesn, but only on the length of the shortest path. Depending on the position of the goal state, the complexity can be at mostO (n).It can be concluded that the choice of the function which evaluates the emotional state of the agent plays a decisive role in solving the problem efficiently. That function should give as detailed information as possible about the consequences of the agent's actions, starting even from the initial state. In this way the function implements properties of human emotions.
Successful laparoscopic surgery for a uterine leiomyoma in a mare
Authors: Muurlink T. , Walmsley J. , Whitton C.
Published: October 2008

Leiomyomas are the most common of uterine tumours in mares but large tumours are rare. A case with a 15 cm uterine leiomyoma diagnosed by rectal palpation and ultrasound examinations with apparent adverse effects on fertility is reported. Management of the case was by hand assisted laparoscopic tumour removal and unilateral ovariectomy. Complications included post operative pain, tachycardia and wound infection. The mare was confirmed to be in foal after her first cover post surgery.
Bacterial pneumonia and pleuropneumonia in sport horses: 17 cases (2001–2003)
Authors: Ferrucci F. , Zucca E. , Croci C. , Di Fabio V. , Martino P. A. , Ferro E.
Published: October 2008

Seventeen racehorses were referred with a history of poor performance, recurrent fever, coughing and/or nasal discharge. All patients underwent a thorough diagnostic procedure, including physical examination, complete blood count, plasma fibrinogen estimation, arterial blood gas analysis, thoracic radiology and ultrasonography, endoscopy, tracheal aspiration with cytological and cultural evaluation, including sensitivity test. According to these procedures, bacterial pneumonia was diagnosed in 14 horses and bacterial pleuropneumonia in 3 horses.Streptococcusspp. were isolated in 11 cases (61.2%),Rhodococcus equiin 3 cases (16.6%),Klebsiella pneumoniaein 3 cases (16.6%) andPseudomonas aeruginosain one case (5.6%).
A review of the use of moxidectin in horses
Authors: Schumacher J. , Taintor J.
Published: October 2008

Moxidectin has broad‐spectrum anti‐nematodal and anti‐arthropodal activities in the horse but is not effective against tapeworms or flukes. Moxidectin and ivermectin have the same efficacy against internal, adult parasites of horses. Moxidectin, however, is highly effective in eliminating encysted and hypobiotic larval stages of cyathostomins, whereas ivermectin is not. Treatment of horses with moxidectin results in an egg‐reappearance period (ERP) of 15–24 weeks. Because of its long ERP, moxidectin is labelled to be used at 12 week intervals. Moxidectin may provide protection against infection by ingested cyathostomin larvae for 2–3 weeks after it is administered.

The larvicidal activity of moxidectin has often been compared to that of fenbendazole administered at either 7.5 or 10 mg/kg bwt for 5 consecutive days. The efficacy of fenbendazole, when administered daily for 5 consecutive days at 7.5 or 10 mg/kg bwt, against all stages of cyathostomins is often less than that of moxidectin because resistance of cyathostomins to benzimidazoles is prevalent worldwide, and the 5 day course of fenbendazole does not overcome this resistance. There are now reports of resistance of ascarids to moxidectin. Overt resistance of cyathostomins and a shortened egg re‐emergence period after treatment with moxidectin have been reported. Rapid removal of manure by natural fauna can significantly reduce larval nematode concentrations and thereby reduce intervals of anthelmintic treatment. Of the macrocyclic lactones, moxidectin has the least deleterious effect on faecal fauna.
Simplified Dynamic Analysis of Barge Collision for Bridge Design
Authors: Consolazio Gary R. , Davidson Michael T.
Published: October 2008

The AASHTO design provisions for barge impact on bridges spanning navigable waterways use a static force approach to determine structural demand on bridge piers. Recently, however, full-scale experimental dynamic tests of barge impact have indicated that consideration should also be given to additional forces generated from dynamic effects. Specifically, mass-related inertial forces generated by the superstructure of a bridge can restrain underlying pier columns and lead to dynamic amplification of column design forces. This paper presents an algorithm for performing simplified, coupled dynamic barge impact analysis for bridge structures. This type of analysis yields structural design forces, with dynamic amplifications included, on the basis of characteristics of the design impact condition (barge mass and speed). Results from the proposed simplified analysis method are validated using full-scale experimental test data and are compared with results obtained from full-resolution analyses for a variety of barge impact energies and bridge types.
Evaluating Suspension Bridge Cables on North America's Busiest International Crossing
Authors: Blasko Paul D. , Borzok Michael J. , Kulicki John M.
Published: October 2008

The main cables of the Ambassador Bridge—carrying four lanes of traffic over the Detroit River between Detroit, Michigan, and Windsor, Ontario, Canada—have recently been inspected internally for the first time, after 78 years of service. The bridge has a suspended main span of 1,850 ft, with back spans consisting of trusses supported on steel bents. The main cables comprise 37 strands of 218 wires each, protected with red lead paste. The wires are No. 6 gauge, cold drawn and double galvanized, with a specified minimum tensile strength of 215 ksi. Cable strength was calculated by means of the procedures of NCHRP Report 534: Guidelines for Inspection and Strength Evaluation of Suspension Bridge Parallel Wire Cables. Four locations were inspected along the length of each cable, and wire samples removed for testing. All three models presented in NCHRP Report 534 were used to estimate cable strength: the simplified strength model, the brittle wire model, and the limited ductility model. Modifications to the NCHRP procedure were required for the unloaded backstay locations. The results of the evaluation showed the cables to be in very good condition, with a calculated factor of safety of 2.70, which was based on the limited ductility model. The reduction in strength from the as-built condition was less than 10% at the worst location.
Comparison of Standard Load and Load and Resistance Factor Bridge Design Specifications for Buried Concrete Structures
Authors: Miller Larry J. , Durham Stephan A.
Published: October 2008

For the past 30 years, it has been common practice to use AASHTO standard design specifications for underground precast concrete structures. Today, the bridge engineering profession is making the transition from the standard AASHTO load factor design bridge specifications to the load and resistance factor design (LRFD) specifications. The FHWA has mandated that all culverts, retaining walls, and other standard structures designed after October 2010 be designed according to the AASHTO LRFD bridge design specifications for a project to receive federal funding. This paper compares related provisions from both specifications used in designing underground concrete structures, such as underground utility structures, drainage inlets, three-sided structures, and box culverts. Although many provisions of these two codes are the same, important differences could have a significant impact on the amount of reinforcement, member geometry, and cost to produce buried reinforced concrete structures. Many AASHTO LRFD code provisions that differ from the standard specifications include terminology, load factors, implementation of load modifiers, load combinations, multiple presence factors, design vehicle live loads, distribution of live load to slabs and earth fill, live load impact, and live load surcharge. This study demonstrates that greater reliability and a more uniform factor of safety are obtained when the LRFD specifications are used.
Static Load Tests of Posttensioned, Prestressed Concrete Road Bridge over Reservoir Water Plant
Authors: Mordak Arkadiusz G. , Manko Zbigniew
Published: October 2008

This paper presents the results of field load tests on four spans of a post-tensioned, prestressed concrete road bridge over a reservoir water plant on the Nysa Klodzka River in Topola, Poland, under static loads. The spans were especially designed for B-class loads (400 kN) according to Polish load standards. They underwent a whole range of research, which included testing bridge deck slab deflections under trial static (and dynamic) loads. The tests were performed on October 28, 2002.
Dynamic Boundary Element Method Analysis for Determining Correction Factor in Impact Echo
Authors: Alver Ninel , Ohtsu Masayasu
Published: October 2008

The impact echo method is a nondestructive testing method that is based on the use of elastic waves. It has been widely used in the nondestructive evaluation of concrete. With the identification of the peak frequency observed in the frequency spectrum, the depth of a reflector can be estimated when the longitudinal wave velocity is known. However, in most applications, an empirical correction factor (β) is used because the frequency observed in the spectrum is not in good agreement with the frequency calculated by the given equation in the impact echo. This paper presents determination of the empirical shape factor, β, in impact echo for different rectangular shapes. Two-dimensional dynamic boundary element analysis was conducted as a frequency sweep to simulate the impact test. The deformation modes of the first-mode resonance were examined for each shape by applying boundary element method analysis.
Seismic Design and Ductility Evaluation of Thin-Walled Steel Bridge Piers of Box Sections
Authors: Mamaghani Iraj H. P.
Published: October 2008

This paper deals with seismic design and ductility evaluation of thin-walled steel bridge piers of box sections supporting highway bridge superstructures. The basic characteristics of the thin-walled steel box section structures are noted. A seismic design method for ultimate strength and ductility evaluation of thin-walled steel bridge piers of box sections is presented. The application of the method is demonstrated by comparing the computed strength and ductility of some bridge piers with test results. The method is applicable to both the design of new, and the retrofitting of existing, thin-walled steel bridge piers of box sections. The effects of some important parameters, such as width-to-thickness ratio, column slenderness ratio, and residual stress, on the ultimate strength and ductility of thin-walled steel bridge piers of box sections are presented and discussed.
Carbon Fiber-Reinforced Polymer Strand Application on Cable-Stayed Bridge, Penobscot Narrows, Maine
Authors: Jay Rohleder W. , Tang Benjamin , Doe Thomas A. , Grace Nabil F. , Burgess Christopher J.
Published: October 2008

Maine's first cable-stayed bridge opened to traffic on December 30, 2006. Designed as an emergency replacement for the Waldo–Hancock Bridge, the new bridge uses an innovative cradle system to carry the stays from the bridge deck through the pylon and back to the bridge deck. Each strand is anchored independently; thus, strands may be removed, inspected, and replaced while the bridge carries traffic. This advantage, coupled with Maine Department of Transportation concerns for the premature loss of the Waldo–Hancock Bridge due to corrosion, created interest in an opportunity to install and monitor representative carbon fiber-reinforced polymer (CFRP) strands in the cable stays of this bridge. CFRP strands were installed for the purposes of assessing their performance in a service condition and evaluating them for use on future bridges. Three representative stays in the bridge were designed to include two reference strands each, which may be removed and not replaced without change to the bridge's structural integrity. Six epoxy-coated steel strands were removed and successfully replaced with CFRP strands in June 2007. Data are being collected from the monitoring equipment installed on all of the strands (both traditional steel and CFRP strands) in the bridge to evaluate CFRP strand performance for future bridge cable stay and post-tensioning installations. The bridge location ensures that the test strands will be evaluated under a wide range of temperatures and variety of wind loads.
Integrated Monitoring System for Carbon Composite Strands in Cable-Stayed Bridge, Penobscot Narrows, Maine
Authors: Berube Keith A. , Lopez-Anido Roberto A. , Caccese Vincent
Published: October 2008

An integrated monitoring system for carbon fiber composite cable (CFCC) strands recently implemented in the Penobscot Narrows Bridge in Maine is presented. This cable-stayed bridge features a cradle-stay system in the pylons that provides a continuous cable stay between the main span bridge deck anchorage and the back span bridge deck anchorage. The cradle-stay system allowed for replacing epoxy-coated steel strands with CFCC strands. The monitoring system installed in the bridge is composed of a set of sensors and devices that provide complementary structural information: (a) load cells supported on steel anchorage chairs, (b) linear voltage differential transformers (LVDTs) mounted on the steel anchorage chairs, (c) fiber-optic strain (FOS) sensors embedded in composite sleeves, and (d) temperature sensors. The monitoring system was designed to detect variations over time in individual carbon fiber strand force and strains at the anchorage locations and to correlate the measurements with ambient temperature. Laboratory tests were conducted to proof-load the steel anchorage chairs and to calibrate the LVDTs and embedded FOS strain measurement systems. The baseline response of the CFCC strands that was based on load cell, FOS sensors, and LVDTs measurements after the strand stressing operation is presented. The CFCC strands experienced changes in tensile force between +3% and −5% over the first 4 months in service, which were consistent with ambient temperature fluctuations. The FOS measured strand strains and the LVDT deflections of the anchored chair exhibited trends consistent with the variations in CFCC strand force.
Orodispersible Tablets of Carbamazepine Prepared by Direct Compression Method Using 32 Full Factorial Design
Authors: Swamy PV , Shahidulla SM , Shirsand SB , Hiremath SN , Ali Md Younus
Published: October 2008

Orodispersible tablets of carbamazepine were prepared with a view to enhance patient compliance by direct compression method using 3Â² full factorial design. Crospovidone (2-10% w/w) was used as superdisintegrant and microcrystallinecellulose (0-30% w/w) was used as diluent, along with directly compressible mannitol to enhance mouth feel. The tablets were evaluated for hardness, friability, thickness, drug content uniformity, in vitro dispersion time, wetting time and water absorption ratio. Based on in vitro dispersion time (approximately 10 s); the formulation containing 2% w/w crospovidone and 30%w/w microcrystallinecellulose was found to be promising and tested for in vitro drug release pattern (in pH 6.8 phosphate buffer), short-term stability (at 40Âº/75 % RH for 3 w) and drug-excipient interaction. This formulation showed four-fold faster drug release (t25%) compared to the conventional commercial tablet formulation. Short-term stability studies on the formulation indicated that there are no significant changes in drug content and in vitro dispersion time (p < 0.05).Key words: Orodispersible tablets, carbamazepine, crospovidone, micro crystallinecellulose, 3Â² full factorial designDOI = 10.3329/dujps.v7i1.1199Dhaka Univ. J. Pharm. Sci. 7(1): 1-5, 2008 (June)
Hepatoprotective Effects of Thespesia lampas Dalz & Gibs in CCl4 Induced Liver Injury in Rats
Authors: Sangameswaran B , Deshraj Chumbhale , Balakrishnan BR , Jayakar B
Published: October 2008

The extracts of the roots of Thespesia lampas (Malvaceae) were evaluated for hepatoprotective activity in rats by inducing chronic liver damage by subcutaneous injection of 50% v/v carbon tetrachloride in Tween 80 at a dose of 3ml/kg for a period of 4 weeks. The biochemical parameters like serum glutamate pyruvate transaminase (SGPT), serum glutamate oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP), serum bilirubin and total proteins were estimated to assess the liver function. Hepatic steatosis, centrilobular necrosis, and often swelling of the hepatic cytoplasm were observed in carbontetra chloride treated group, while these were completely absent in the extracts of T. lampas (300 mg/kg b.wt) treated groups (p < 0.01). The present investigation established pharmacological evidence to support the folkloric claim of hepatoprotective activity of T. lampas.Key words: Thespesia lampas, Carbon tetrachloride, Hepatoprotective, Rats, Root extracts Â DOI = 10.3329/dujps.v7i1.1201Dhaka Univ. J. Pharm. Sci. 7(1): 11-13, 2008 (June)
The In vitro Effects of Atenolol and Zinc Chloride on the Protein Binding of Amlodipine in Aqueous Medium
Authors: Amran Md Shah , Morshed Sheikh Niaz , Khandakar Md Jahangir Alam , Rahman Md Masudur , Rahman Md Mosiur , Hossain Md Amjad
Published: October 2008

An in vitro study of protein binding has been carried out to observe the influence of atenolol and zinc chloride on the protein binding of amlodipine by equilibrium dialysis method at 37Â±1 0C and at physiological pH (7.4). It has been found that zinc chloride lowered the affinity and percentage of protein binding of amlodipine to bovine serum albumin but atenolol has no such effect. The Scatchard plots were prepared to reveal the number of binding sites and the affinity for protein binding. It was seen that the highest percentage binding of amlodipine was 91% and the lowest was 74%. In the presence of atenolol, the highest and the lowest value of percentage of protein binding was 90% and 72%, respectively. In the presence of zinc chloride these values were 84% and 65% respectively. It is, thus, inferred that atenolol or its complex with amlodipine has no significant effect on percentage of protein binding of amlodipine. While zinc chloride or its complex with amlodipine can cause a decrease in percentage of protein binding of amlodipine. Complexation of amlodipine with zinc chloride might, therefore, displace the drug from the plasma and the displaced drugs may be redistributed, thus , increasing the free drug in plasma and tissue systems. This may change the pharmacokinetic properties of the drug and may affect the pharmacological and toxic effects. It is thus inferred that care and monitoring must be taken during combination therapy of amlodipine and zinc chloride. Key words: Amlodipine, protein binding, binding site, equilibrium dialysis, Scatchard plot, atenolol, zinc chloride, combination therapy Â DOI = 10.3329/dujps.v7i1.1202Dhaka Univ. J. Pharm. Sci. 7(1): 15-21, 2008 (June)
Antineoplastic Activity of Bis-tyrosinediaqua Ni(II) Against Ehrlich Ascites Carcinoma
Authors: Khanam Jahan Ara , Salahuddin M Sultan , Habib M Rowshanul , Islam M Rafiqul , Jesmin Mele , Sarker M Kumar , Ali M Mohsin
Published: October 2008

In order to find out new compounds having antineoplastic activity, bis-tyrosine diaqua nickel (II) complex was synthesized and characterized. The antineoplastic activity of the compound was judged by measuring inhibition of tumour growth and enhancement of survival time of EAC cell bearing mice. In addition its effects on haematological parameters and serum alkaline phosphatase activity of both normal and EAC bearing mice were also studied. The test compound significantly inhibited the tumour growth and increased life span of tumour bearing mice at dose 10 mg/kg i.p. The treatment also recovered the perturbed haematological parameters as well as the serum alkaline phosphatase activity towards normal. The host toxicity of the test compound was found to be negligible. The compound can be considered as an effective antineoplastic agent. Key words: Antineoplastic activity, Bis-tyrosinediaqua nickel (II), EAC, ALP activity Â DOI = 10.3329/dujps.v7i1.1215 Dhaka Univ. J. Pharm. Sci. 7(1): 33-37, 2008 (June)
In vitro Release Kinetic Study of Esomeprazole Magnesium from Methocel K15M and Methocel K100 LVCR Matrix Tablets
Authors: Biswas Bishyajit Kumar , Islam Md Safiqul , Begum Farida , Rouf Abu Shara Shamsur
Published: October 2008

In the present study esomeprazole sustained release tablet matrix was prepared by utilizing different grades of hydroxypropyl methylcellulose (HPMC) polymers such as Methocel K15M & Methocel K100 LVCR by direct compression method. Different amount of Methocel K15M was used to develop matrix builder in the seven proposed formulations (F1-F7) for the study of release rate retardant effect at 20%, 25%, 30%, 35%, 40%, 45% and 50% of total weight of tablet matrix respectively. The dissolution study of Methocel K15M based tablet matrices of those proposed formulations were carried out in the simulated gastric medium (pH 1.3) for first two hours and then in the simulated intestinal medium (pH 6.8) for 8 hours using USP dissolution apparatus II. The formulation F-5 (40%) and F-6 (45%) met the optimum release rate of esomeprazole for 10h period of in vitro dissolution study. The release kinetics of formulation F-5 and F-6 very closely followed Higuchi kinetic order than first order and zero order kinetics. Similarly Methocel K100 LVCR was used to develop matrix builder in another seven proposed formulations (F8-F14). It was found that formulations F-11 (35%), F-12 (40%) and F-13 (45%) met the desired release rate of esomeprazole for 10h period. The release kinetics of formulation F-11, F-12 and F-13 followed Higuchi kinetic order. Between these two polymers, Methocel K100 LVCR showed better release retardant effect than Methocel K15M. Key words: Esomeprazole, Direct compression, Controlled release, Methocel K15M and Methocel K100 LVCRDOI = 10.3329/dujps.v7i1.1216 Dhaka Univ. J. Pharm. Sci. 7(1): 39-45, 2008 (June) Â
Preliminary Cytotoxicity Screening of Some Medicinal Plants of Bangladesh
Authors: Rahman Mohammad S , Begum Bilkis , Chowdhury Rasheduzzaman , Rahman Khondaker M , Rashid Mohammad A
Published: October 2008

The cytotoxic activity of the methanolic extracts of 35 plant species, including 28 traditionally used plants of Bangladesh was evaluated by the brine shrimp lethality bioassay technique. Among these, 19 plant extracts exhibited significant toxicity to brine shrimps with LC50 less than 10 Î¼g/ml.Key words: Cytotoxic activity, Brine shrimp lethality bioassay.DOI = 10.3329/dujps.v7i1.1217Dhaka Univ. J. Pharm. Sci. 7(1): 47-52, 2008 (June)
Preparation and In vitro Evaluation of Theophylline Loaded Gastroretentive Floating Tablets of METHOCEL K4M
Authors: Khan Ferdous , Razzak Md Shaikhul Millat Ibn , Khan Md Ziaur Rahman , Azam Kazi Rashidul , Sadat Sams Mohammad Anowar , Reza Md Selim
Published: October 2008

This investigation describes the preparation and in vitro evaluation of gastroretentive floating tablets of theophylline. Hydrophilic polymer METHOCEL K4M was used for its gel forming and release controlling properties. Sodium bicarbonate and citric acid were incorporated as gas generating agents. The effects of soluble components (sodium bicarbonate and citric acid), gel forming agent (METHOCEL K4M) and dose variation on drug release profile and floating properties were investigated. It has been observed that in all cases increase of the amount of floating agent caused a decrease of the floating lag time. Increase of theophylline load showed an increase of the floating lag time, which was independent of floating agent content. The release mechanisms were explored and explained with zero order, first order, Higuchi, Korsmeyer and Hixon-Crowell equations. The release rate, extent and mechanisms were found to be governed by the content of polymer and floating agent. The content of active ingredient was also a vital factor in controlling drug release pattern. It was found that polymer content and amount of floating agent significantly affected the time required for 50% of drug release (T50%), percentage drug release after 8 hours, release rate constant, and diffusion exponent (n). Kinetic modeling of dissolution profiles revealed that the drug release mechanism could range from diffusion controlled to case II transport, which was mainly dependent on presence of relative amount of theophylline, polymer and floating agent. Key words: Gastroretention, Floating tablet, Theophylline Â DOI = 10.3329/dujps.v7i1.1220 Dhaka Univ. J. Pharm. Sci. 7(1): 65-70, 2008 (June)
Triterpenoids from the Stem Bark of Crataeva nurvala
Authors: Haque Md Enamul , Islam Md Nahidul , Gupta Dipankar Das , Hossain Mahbub , Shekhar Hossain Uddin , Shibib Biazid Alam
Published: October 2008

Two triterpenoids, phragmalin triacetate (1) and lupeol (2) were isolated from an ethyl acetate extract of the stem bark of Crataeva nurvala (Capparidaceae) by repeated chromatography over silica gel. The structures of these compounds were determined by spectroscopic analyses (UV, IR, 1H NMR, 13C NMR and EIMS). This is the first report of the systematic phytochemical investigation and the presence of these compounds 1 and 2 from this plant. Key words: Crataeva, Capparidaceae, Phragmalin triacetate and Lupeol. Â DOI = 10.3329/dujps.v7i1.1221 Dhaka Univ. J. Pharm. Sci. 7(1): 71-74, 2008 (June)
In vitro Release Kinetics Study of Ambroxol Hydrochloride Pellets Developed by Extrusion Spheronization Technique Followed by Acrylic Polymer Coating
Authors: Ahmed Ishtiaq , Roni Monzurul Amin , Kibria Golam , Islam Muhammad Rashedul , Jalil Reza-ul
Published: October 2008

The aim of the present study was to investigate the effect of Ammonio Methacrylate Copolymer Dispersion Type A (Eudragit RL 30 D) and Ammonio Methacrylate Copolymer Dispersion Type B (Eudragit RS 30 D) combination in different weight ratios on the release kinetics of Ambroxol Hydrochloride from coated pellets. Microcrystalline cellulose, lactose, maize starch, hydroxypropyl methylcellulose and the drug was incorporated in the nuclei prepared by Extrusion-Spheronization technique which was coated with Eudragit RL 30D and Eudragit RS 30D in 1:1,1:1.5,1:2,1:2.5 and 1:3 ratios. The in vitro dissolution studies were carried out in 0.1N HCl for 1 hour followed by phosphate buffer (pH 6.8) for 11 h with USP dissolution apparatus Type-II. Drug release decreased with increasing amount of Eudragit RS 30 D in all cases. The drug release followed first order and Higuchi release kinetics. The Korsmeyer plot revealed n=0.50-0.61 or non-Fickian transport mechanism for drug release. From one way ANOVA it was found that the ratio of binary polymer mixer had significant (p < 0.05) effect on drug release. Key words: Aqueous coating, Eudragit, release kinetics, pellet, extrusion-spheronization Â DOI = 10.3329/dujps.v7i1.1222 Dhaka Univ. J. Pharm. Sci. 7(1): 75-81, 2008 (June)
Comparison of Urinary Iodine, Urinary Arsenic, Radioiodine Uptake, Thyroid Stimulating Hormone (TSH) and Free Thyroxin (FT4) Levels, Between Experimental Group with Simple Diffuse Goiter and Control Group
Authors: Hossain Md Sharif , Begum Fatema
Published: October 2008

In Bangladesh some researchers have done several studies to find the correlation of simple diffuse goiter with arsenic level but no one conducted any study to find the differences of urinary iodine, urinary arsenic, radioiodine uptake, the thyroid stimulating hormone (TSH) and free thyroxin (FT4) levels between goitrous and non goitrous. That is why, in this research an attempt has been made to compare the urinary iodine, urinary arsenic, radioiodine uptake, TSH and FT4 levels between experimental group with simple diffuse goiter and healthy control group. In this study another purpose has also been made to find the associations between different pairs of variables for both experimental and control group. In this study we have tried to find the impacts of arsenic level on simple diffuse goiter. This is a case-control analytical study. The study is carried out in the Institute of Nuclear Medicine and Ultrasound, in collaboration with the thyroid out patient department of Bangabandhu Sheikh Mujib Medical University. A total of eighty five (85) subjects are included in the study. Among the 85 subjects, a sample of forty five is considered for experimental group with simple diffuse goiter and another sample of forty is considered for healthy control group without any thyroid disease. From the experimental results it has been found that, the arsenic levels, FT4 and radioiodine uptake levels at 2 hours between the experimental and control groups are significantly different but the urinary iodine levels, TSH levels and radioiodine uptake levels at 24 hours between the experimental and control groups are not statistically different. From the experimental results it has also been found that there is significant differentiation between experimental and controls groups in respect of association between different pairs of variables. In this study, another significant finding is that iodine deficiency is not only the factor of causing simple diffuse goiter, but arsenic level is also one of the most important factor of causing simple diffuse goiter. Key words: Iodine deficiency, Simple diffuse goiter, Urinary arsenic, Statistical analysis, Association, Experimental and Control groups Â DOI = 10.3329/dujps.v7i1.1224 Dhaka Univ. J. Pharm. Sci. 7(1): 89-98, 2008 (June)
Antimicrobial and Cytotoxic Activities of Bryophyllum daigremontianum
Authors: Nahar Kamrun , Khan Mohammad GU , Rahman Mohammad S , Begum Bilkris , Rashid Mohammad A
Published: October 2008

DOI = 10.3329/dujps.v7i1.1227Dhaka Univ. J. Pharm. Sci. 7(1): 99-101, 2008 (June)
‘Choreography’ is Narrative: The Programmes of the Eighteenth-Century Ballet d'Action
Authors: NYE EDWARD
Published: October 2008

In the 1760s, a change in the meaning of the French word ‘chorégraphie’, coined by Feuillet in 1700, coincides with the coming of age of the ballet d'action. At the time when Jean-Georges Noverre, Gasparo Angiolini and others are developing mime dance into a highly elaborate and aesthetically complex stage art, their contemporaries are beginning to use ‘chorégraphie’ to mean the dramaturgical structure of the work rather than a system of notation. The semantic shift suggests that drama is as fundamental to the ballet d'action as a Feuillet transcription is to danse noble. The analogy is sometimes taken further so that ‘chorégraphie’ probably refers to a written plot summary or ballet programme. This has many consequences for the way we think about the ballet d'action. Firstly, we should regard the ballet d'action as danced drama rather than dramatic dance, and secondly, ballet programmes are not peripheral to performance, but provide what contemporaries understand to be ‘choreographic’ information.