bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic algorithms and hybrid neural network modelling for aluminium stress—strain prediction
Authors: Yang Y Y , Linkens D A , Mahfouf M
Published: March 2014

This paper addresses the design of genetic algorithms in developing a hybrid neural network model for aluminium alloy flow stress prediction. The hybrid neural network model consists of a parallel grey-box model structure, with the resulting predictions combining the outputs from the constitutive equations and a neural network. Previous work shows that the hybrid neural network model can deliver better model performance than a neural network model or the constitutive equations. However, the level of performance improvement of the hybrid model depends on the quality of the constitutive model used. This motivates the search for a better constitutive model, with genetic algorithms being employed to optimize its parameters. The advantage of genetic algorithms is that they do not require any gradient information nor continuity assumption in searching for the best parameters. A number of genetic optimization schemes, with different coding schemes (such as binary coding and real-value chromosomes) and different genetic operators for selection, crossover and mutation, have been investigated. The real-value coded genetic algorithms converge much more rapidly and are more efficient since there is no need for chromosome encoding and decoding. Compared with previous work, the resulting hybrid model performance has been improved, mainly in the generalization capability and with a simpler neural network structure. Also, the model response surfaces are much smoother and more metallurgically convincing.
Friction identification using the Karnopp model, applied to an electropneumatic actuator
Authors: Ravanbod-Shirazi L , Besancon-Voda A
Published: March 2014

In this paper, friction identification is studied. After analysing the Karnopp model behaviour, a simple method based on three steps is presented for identifying its parameters. In the first step, the system mass and slip friction parameters are estimated. In the second step, based on the results obtained in the first step, the stick-slip border parameter (limited velocity) is determined, while in the third step the stiction force is estimated. The method is tested in simulation and in an experimental electropneumatic servo showing its high degree of efficiency.
Control and safety aspects of medical robots for treatment of diseases of the prostate
Authors: Phee L , Xiao D , Yuen J , Lau W , Cheng C , Ng W S
Published: March 2014

There has been much advancement in the field of minimally invasive surgery in recent years. Medical robots play an important role in these improvements. Surgeons are fast accepting the aid of robots in laparoscopic, thorascopic, endoluminal and arthroscopic interventions, to name just a few. This paper reviews the state-of-the-art of medical robots that have been and are being developed for the purpose of treating diseases of the prostate. The main objective of these robots is to manoeuvre accurately a surgical tool via the transrectal or transurethral route to perform a surgical procedure on the prostate based on ultrasound guidance. The system approaches and control methodologies of these robots are highlighted. However, the main emphasis is on the safety aspects, both hardware and software, which are discussed in detail. Many of these safety features have been incorporated in the mentioned medical robots to enhance their reliability and safety.
Analysis of rigid-body dynamics for closed-loop mechanisms—its application to a novel satellite tracking device
Authors: Jones T P , Dunlop G R
Published: March 2014

A general method for analysing the velocity and acceleration kinematics of parallel mechanisms is introduced. A method for analysing the forces experienced by rigid bodies in parallel mechanisms is then introduced, which builds on the kinematics that result in a solution to the dynamics of rigid bodies in parallel mechanisms.
Motion design and implementation for a hybrid drive system
Authors: Kireçci A , Dülger L C
Published: March 2014

This paper presents a study of motion design and its implementation on a hybrid drive system that combines the motions of a large constant speed motor with a small servo motor by means of a mechanism in order to provide a powerful programmable drive system. In general, the most suitable function used to generate motion curves is the power form of polynomial functions. However, this function may produce some unexpected oscillations between the boundary conditions. A methodology is given to prevent this drawback of the interpolation function. A laboratory type set-up is designed and manufactured in order to realize the problems of practical implementation. An experimental application involving the hybrid drive system is included in the study presented.
A stable neural adaptive force controller for a hydraulic actuator
Authors: Daachi B , Benallegue A
Published: March 2014

In this paper a neural network adaptive force controller is proposed for a hydraulic system. The dynamic model of this system is highly non-linear and very complex to obtain. Thus, it is considered as a black box and a priori identification becomes necessary. A neural network is used to approximate the model and then a controller using the Lyapunov approach is designed. The neural network parameters are updated online according to an adaptation algorithm obtained via stability analysis. The performance of the proposed neural network controller is validated on an experimental plant.
Adaptive vibration active control of fluid pressure pulsations
Authors: Jiao Z , Chen P , Hua Q , Wang S
Published: March 2014

Conventionally, passive hydraulic absorbers are utilized in order to reduce the vibrations of the fluid power supply systems. It is very difficult to adapt the variable operation conditions, such as inconsistent vibration frequency and varying loads. This paper presents a new vibration active control method to diminish the vibrations of the fluid power supply efficiently. This method is adaptive and robust in controlling the fluctuating frequencies and load disturbances and is capable of keeping the vibrations at a minimum level under variable pump speeds. This paper illustrates the theory and experimentation of vibration active control of a fluid power supply pipeline system in detail. The multilayer piezoelectric technology (PZT) driven orifice valve is designed with characteristics of a proportional opening area to the control voltage, a high-frequency bandwidth and small size. The adaptive-optimum control method is adopted to adjust the control parameters at any instant against emerging disturbances. Based on the test rig, different vibration control methods were applied; the results indicate and confirm the validity of this principle.
Measuring the relative humidity of humid air using a hair hygrometer
Authors: Mehrabian M A , Hashemian M
Published: March 2014

An instrument has been designed and constructed to allow direct measurement of the relative humidity of humid air. The objective of the study is to use the effect of humidity on the linear expansion of a piece of hair that is pulled with a spring or a small weight while exposed to the humid air. This can result in producing such an instrument if the hair sample is specific. For the hair used in this work, relative humidities ranging from 0 to 100 per cent result in a one-dimensional change of about 0.02m/m. As the humidity of the air is decreased or increased, the hair is shortened or lengthened and turns the pointer connected to its end. The pointer detects the relative humidity of humid air on a calibrated plate. A series of experimental data are extracted in different environments using this instrument. The data are in good agreement with the results obtained from the psychrometric chart and mass transfer calculations.
Fuzzy logic control for use in in-pipe mobile robotic system navigation
Authors: Ong J K , Bouazza-Marouf K , Kerr D
Published: March 2014

This paper presents a fuzzy logic control for the navigation of a mobile robotic system in gas pipelines. The robotic system is designed for a local gas distribution pipeline network with 150–300mm diameter pipes; common pipe fittings in use are straight and bend sections, reducers and slope pipe sections. The navigation problem forms a part of the current development of a new modular and semi-autonomous vehicle system. The vehicle control and navigation technique is implemented using a two-mode controller consisting of a proportional-integral-derivative (PID) and fuzzy logic control. The PID controller is responsible for direct control of the actuators, while the fuzzy logic controller is used to evaluate as well as to define the sensor outputs such as speed, climbing angle and rate of climbing angle in order to perceive the different types of pipe environment and vehicle actions. Since the navigation problem involves a multivariable input-output (MIMO) system, a cascaded hierarchical fuzzy model configuration is used to reduce the dimensionality of the fuzzy model. The fuzzy navigation controller is thus an interlink fuzzy subsystem of the pipe environment recognition and action adjustment subsystems. Results of simulations and laboratory experiments are presented to demonstrate the ability of the control strategy. A brief description of the mobile robotic system used is presented as background.
The role of resonance in elementary hydraulic switching control
Authors: Scheidl R , Hametner G
Published: March 2014

Elementary hydraulic switching control aiming at energy efficiency can be done by connecting a hydraulic cylinder alternately with a high pressure and a tank line in a pulse width controlled mode. The switching frequency is crucial for the energetic efficiency as well as for the speed fluctuation of the generated motion. This paper clarifies why and in which way the efficiency optimal switching frequency is related to some resonance condition. A simple non-linear, non-dimensional, second-order differential equation is derived that represents the dynamic behaviour of the drive system. It is investigated by asymptotic expansion methods. If valves with a relatively small nominal flowrate are used the optimal frequency is close to the natural frequency of the load oscillating in the hydraulic cylinder's compressible hydraulic fluid. Larger valves enable higher efficiency and weaken the role of resonance. The optimal frequency becomes smaller.
Piezoelectromagnetic smart structures
Authors: Hyder S J , Sunar M , Mahmood F
Published: March 2014

A piezoelectromagnetic medium is formed by bonding piezoelectric and magnetostrictive layers on tapered beams. Piezoelectromagnetic materials are often utilized as intelligent media in the design of distributed sensors and actuators of smart structures. A spectral finite element model is presented for evaluating the voltage and magnetic response of flexible structures subjected to modulated force input. The Taguchi methodology is applied as a robust design technique to study the effect of design variables such as the thickness of the magnetostrictive and piezoelectric layers, the taper ratio of the tapered beam and the boundary conditions. From the study it is concluded that the thickness of the magnetostrictive and piezoelectric layers and the taper ratio of the beam contribute significantly to the response of the structure considered.
Self-learning control applied to vibration control of a rotating spindle by piezopusher bearings
Authors: Li W , Maißer P , Enge H
Published: March 2014

Vibration suppression of rotating machinery is an important engineering problem. For several years, researchers have demonstrated that this vibration could be greatly reduced for machines by active control using active actuators. In this paper, active control that uses innovative active piezoceramic pusher bearings and self-learning control for the rotor system with varying initial state errors is presented and applied. To deal with the problems of initial state errors at each iteration, the D-type iterative learning control is combined with feedback compensation. The rule library of self-learning control according to all criteria, for example operating speed, is set up by hybrid control. The algorithms are coded in Visual Basic. Their performance is examined experimentally on a laboratory rotor rig. The results clearly demonstrate the more effective vibration suppression of unknown synchronous, subsynchronous and other transient and stochastic disturbances that can be achieved using innovative active piezoceramic pusher bearings with self-learning control.
Stability robustness of linear output feedback systems with both time-varying structured and unstructured uncertainties as well as actuator saturation
Authors: Chen S-H , Chou J-H
Published: March 2014

This paper investigates the stability robustness of linear output feedback systems with actuator saturation as well as both time-varying structured (elemental) and unstructured (norm-bounded) parameter uncertainties by directly considering the mixed quadratically coupled uncertainties in the problem formulation. Based on the Lyapunov approach and some essential properties of matrix measures, a new sufficient condition is proposed for ensuring that the linear output feedback systems with actuator saturation as well as both time-varying structured and unstructured parameter uncertainties are robustly stable. A numerical example is given to illustrate the application of the presented sufficient condition.
Analysis and optimal control of pulse width modulation feedback systems
Authors: Hsieh C-H , Chou J-H
Published: March 2014

This paper considers the analysis and optimization problems of a class of pulse width modulation (PWM) feedback systems by using continuous orthogonal functions. Two algorithms only involving algebraic computation are derived to analyse PWM feedback systems and to design both the optimal control gains and the optimal PWM patterns of PWM feedback systems under the criterion of minimizing a quadratic performance index. The illustrated examples show that the proposed algorithms based on continuous orthogonal functions can obtain satisfactory results.
Water hydraulic high-speed solenoid valve Part 1: Development and static behaviour
Authors: Park S-H , Kitagawa A , Kawashima M
Published: March 2014

This study is concerned with the development of a novel water hydraulic high-speed solenoid valve with a two-stage mechanism. By virtue of the two-stage mechanism and the proposed particular design, which use the leakage flow through the clearance between the main poppet and sleeve as the internal pilot flow, it is possible for the developed valve to have unique features, such as no internal leakage, a switching time of approximately 2 ms, maximum flowrate of 9 1/min and maximum pressure of 14 MPa. Based on the preliminary experimental results using a fabricated prototype valve, the performance of the developed valve has been improved. It can be seen from the experiment that the static flow characteristic according to the duty ratio of the improved valve is very satisfactory. As an application of the developed valve, the speed control of a water hydraulic motor has been conducted using the pulse width modulated (PWM) control of the developed valve. It was found that the developed valve is suitable for the PWM control method and can be implemented as the flow control valve of water hydraulic systems.
Hybrid models for hardware-in-the-loop simulation of hydraulic systems Part 1: Theory
Authors: Ferreira J A , Almeida F Gomes , Quintas M R , Estima de Oliveira J P
Published: March 2014

Physical modelling of hydraulic systems results in systems of differential and algebraic equations (DAEs) that are normally stiff. This is because they often include multiple temporal scales and present complex and non-linear behaviour. The simulation of these stiff DAEs in real time demands small time steps, in order to achieve algorithm stability, because explicit fixed step solvers are usually applied. Modelling some fast dynamics as instantaneous changes in order to reduce the model's stiffness has been an area of research in the last few years. The description of the dynamic behaviour as piecewise continuous modes, interspersed with discrete transitions, together with the reduction in the model complexity, facilitates the use of fixed time step integration methods and thus allows real-time simulation.

The main goal of this work was to obtain not too complex models in order to allow the models to be used in hardware-in-the-loop experiments. This paper proposes the use of the statecharts formalism to describe hybrid behaviour in hydraulic systems and presents semiempirical models of a valve controlled hydraulic cylinder intended to test real controller performance on a hardware-in-the-loop setup. These semiempirical models require less computing power, and it is easier to adjust the model parameters.
The application of initial state correction in iterative learning control and the experimental validation on a piezoelectric tube scanner
Authors: Hinnen K J G , Fraanje R , Verhaegen M
Published: March 2014

In iterative learning control (ILC) it is generally assumed that the initial state is the same at the start of each iteration. In various applications, this assumption is easily violated. In this paper an initial state correction procedure is proposed to take into account the effect of a varying initial state. The algorithm is experimentally validated on a piezoelectric tube scanner. In these experiments, the piezoelectric tube scanner is linearized by means of a Preisach inverse hysteresis model.
Control of vibration in civil structures
Authors: Seto K
Published: March 2014

This paper reports recent trends in active vibration control mainly as developed in Japan for civil structures. Firstly, it classifies vibration control methods and controllers, especially active dynamic absorbers that are widely used in mechanical and civil engineering. Secondly, it addresses basic problems in the control of vibration of flexible structures such as formulating the reduced-order model required for designing vibration controllers, the correct arranging of sensors and actuators, and how to prevent spillover instability. Finally, the practical use of control theories such as linear-quadratic control theory, H∞ control theory, neural network theory and other topics are discussed.
Machine vision in conjunction with a knowledge-based system for semi-automatic control of a gravure printing process
Authors: Brown N , Jackson M R , Parkin R M , Bamforth P E
Published: March 2014

This paper describes the work carried out to produce an automated print inspection system, which was developed on a gravure printing press within the wall-covering printing industry. The project aim was to produce a system that could continuously monitor the gravure printing process, by examining printed material using machine vision, and then by using a fuzzy knowledgebased system to interpret the machine vision system output and to make recommendations to an operator as to how to correct the process with simple text-based suggestions, avoiding printing of scrap material.
Collectivism, individualism, and pragmatism in China: Implications for perceptions of mental health
Authors: Kolstad Arnulf , Gjesvik Nini
Published: March 2014

This study aimed to better understand how minor mental health problems (MMPs) are perceived by well-educated urban dwellers in China who are influenced by Western values. Urban China is a rapidly changing society in which traditional Chinese culture and Western thought coexist. As a result, the established processes of interdependent self-appraisal have been challenged and a sense of a bicultural self has developed among a growing proportion of the population. The fieldwork for this study included interviews and observations. The results are derived mainly from interviews with professional practitioners, students, and lay people from three urban sites. One of the main findings was that respondents who referred to traditional and collectivistic Chinese values tended not to label MMPs as psychiatric disorders or illnesses but as challenges in daily life and relationships strain. While the Western medical model of MMPs considers them a form of illness, they were not viewed in this way in traditional collectivistic China in the past, even among educated urban dwellers. However, the urban and educated Chinese who have developed a stronger sense of a bicultural self are now more likely to perceive and deal with MMPs from a Western viewpoint.
The Ideological and Electoral Determinants of Laws Targeting Undocumented Migrants in the U.S. States
Authors: Zingher Joshua N.
Published: March 2014

State legislatures have been extremely active in passing legislation relating to all facets of immigration policy over the last several years. In this article, I develop a framework that explains how party ideology, party control of the legislature, and electoral conditions affect the likelihood that a state legislature will adopt policies that increase immigration enforcement. I test my arguments using state immigration policy adoption data that span from 2005 to 2011. I find that conservative Republican state parties are more likely to pass legislation enhancing immigration enforcement—on the condition that the Republican Party controls the state's legislative institutions. However, the willingness of Republican-controlled legislatures to pass immigration reform is often tempered by electoral concerns. Republican-controlled legislatures in states where Latinos make up a large proportion of the electorate are significantly less likely to adopt new legislation that targets undocumented migrants. I argue that Republican support for increasing sanctions on undocumented migrants is eroded by the potential for an electoral backlash from Latino voters. Democratic-controlled legislatures are unlikely to pass legislation under any conditions. Ultimately, the observed pattern of policy adoption is the product of the trade-off between the state parties' ideologically driven policy goals and the electoral consequences associated with actually implementing immigration policies.
Forme fruste of isolated right ventricular endomyocardial fibrosis: a case report
Authors: Bunte Matthew , Liao Kenneth , Manivel J Carlos , Missov Emil
Published: March 2014

Introduction

Endomyocardial fibrosis is a neglected tropical disease of unknown etiology and poor prognosis. It is endemic of tropical climates where it is the most common cause of restrictive cardiomyopathy in the second and fourth decades of life. A forme fruste of the disease is thought to be present in temperate climates where the diagnosis remains exceedingly rare.

Case presentation

We describe a case of isolated right ventricular endomyocardial fibrosis in a 27-year-old Caucasian man from a temperate climate who presented initially with frank hemoptysis and pulmonary thromboembolic disease. We further describe the approach utilized in the diagnosis, the surgical treatment and the outcome of the disease.

Conclusions

We conclude that endomyocardial fibrosis should be included in the differential diagnosis of apical cardiomyopathies in patients from temperate climates.
The use of everolimus to target carcinogenic pathways in a patient with renal cell carcinoma and tuberous sclerosis complex: a case report
Authors: Kim Hye Sook , Kim Seung Tae , Kang Seok Ho , Sung Deuk Jae , Kim Chul Hwan , Shin Sang Won , Kim Yeul Hong , Cho Won Yong , Park Kyong Hwa
Published: March 2014

Introduction

An increased understanding of the genetic pathways involved in renal cell carcinoma has resulted in the development of various drugs that target relevant signaling cascades for the specific treatment of this disease. However, no validated predictive markers have been identified to guide the decision whether patients should receive vascular endothelial growth factor–targeted therapy or mammalian target of rapamycin–targeted therapy. We present what is, to the best of our knowledge, the first case of renal cell carcinoma in a patient with tuberous sclerosis complex who was successfully treated with everolimus.

Case presentation

The patient was a 49-year-old Korean woman with tuberous sclerosis complex and recurrent renal cell carcinoma. The patient was treated with the tyrosine kinase inhibitor sunitinib followed by the mammalian target of rapamycin inhibitor everolimus. This treatment resulted in a prolonged response and significant clinical benefit. Notably, everolimus ameliorated the symptoms related not only to renal cell carcinoma but also to tuberous sclerosis complex.

Conclusion

This case provides a rationale for the use of everolimus as first-line treatment for this specific patient population in order to target the correct pathway involved in carcinogenesis.
Polycyclic aromatic hydrocarbons in the coastal sea water, the surface sediment and Mudskipper Boleophthalmus dussumieri from coastal areas of the Persian Gulf: source investigation, composition pattern and spatial distribution
Authors: Sinaei Mahmood , Mashinchian Ali
Published: March 2014

Background

Persian Gulf is an exposed and stressed area as a result of oil pollution and other fossil fuels containing PAHs. The susceptibility of using mudskippers to monitor marine pollution, like PAHs, points to the fact that mudskippers are able to accumulate and record the PAHs presented in the coastal environments.

Methods

Polycyclic aromatic hydrocarbons (PAHs) were examined in the coastal waters, the sediments and biota (i.e., Boleophthalmus dussumieri) along the coast of the Persian Gulf. PAHs concentrations were measured with HPLC method.

Results

Total PAH concentrations in the sea water, the sediments, the liver and the gill tissues ranged between 0.80-18.34 μg/l, 113.50-3384.34 ng g-1 (d w), 3.99-46.64 ng g-1 (d w) and 3.11-17.76 ng g-1 (d w), respectively. PAHs distribution patterns in the sediment and the liver tissue samples were dominated by three-and four-ring structures whereas two-and three-rings were dominated in the water and the gill.

Conclusions

This finding revealed a negative eco-risk effects occasionally occur in this area. The higher presence of low condensate ring structures reflected a predominant origin of petrogenic and some cases of pyrolitic sources.
Voluntary Exercise Adapts the Hypothalamus-Pituitary-Thyroid Axis in Male Rats
Authors: Uribe Rosa María , Jaimes-Hoy Lorraine , Ramírez-Martínez Candy , García-Vázquez Arlene , Romero Fidelia , Cisneros Miguel , Cote-Vélez Antonieta , Charli Jean-Louis , Joseph-Bravo Patricia
Published: March 2014

The hypothalamic-pituitary thyroid (HPT) axis modulates energy homeostasis. Its activity decreases in conditions of negative energy balance but the effects of chronic exercise on the axis are controversial and unknown at hypothalamic level. Wistar male rats were exposed for up to 14 days to voluntary wheel running (WR), or pair-feeding (PF; 18% food restriction), or to repeated restraint (RR), a mild stressor. WR and RR diminished food intake; body weight gain decreased in the 3 experimental groups, but WAT mass and serum leptin more intensely in the WR group. WR, but not RR, produced a delayed inhibition of central markers of HPT axis activity. At day 14, in WR rats paraventricular nucleus-pro-TRH mRNA and serum TSH levels decreased, anterior pituitary TRH-receptor 1 mRNA levels increased, but serum thyroid hormone levels were unaltered, which is consistent with decreased secretion of TRH and clearance of thyroid hormones. A similar pattern was observed if WR animals were euthanized during their activity phase. In contrast, in PF animals the profound drop of HPT axis activity included decreased serum T3 levels and hepatic deiodinase 1 activity; these changes were correlated with an intense increase in serum corticosterone levels. WR effects on HPT axis were not associated with changes in the activity of the hypothalamic-pituitary adrenal axis, but correlated positively with serum leptin levels. These data demonstrate that voluntary WR adapts the status of the HPT axis, through pathways that are distinct from those observed during food restriction or repeated stress.
Suppressed Bone Turnover in Obesity: A Link to Energy Metabolism? A Case-Control Study
Authors: Viljakainen Heli , Ivaska Kaisa K. , Paldánius Päivi , Lipsanen-Nyman Marita , Saukkonen Tero , Pietiläinen Kirsi H. , Andersson Sture , Laitinen Kalevi , Mäkitie Outi
Published: March 2014

Context:

Observations in rodents suggest that osteocalcin (OC) participates in glucose metabolism. Based on human studies, it remains unclear whether circulating OC is simply a bone turnover marker (BTM) or also a mediator in interactions between the skeleton and glucose homeostasis.

Objective:

The objective of the study was to determine the responses of BTMs, including OC, to oral glucose tolerance test (OGTT) in a case-control setting.

Design and Patients:

Thirty-four normoglycemic young adults [mean age 19 y (SD 2.3)] with severe childhood-onset obesity and their gender- and age-matched nonobese controls underwent a standard 2-hour OGTT.

Main Outcome Measures:

Glucose, insulin, and six BTMs including total and carboxylated OC (cOC) were determined at baseline and at 30, 60, 90, and 120 minutes during OGTT.

Results:

The obese and control subjects were similar in height; the mean body mass indices were 40.4 and 21.9 kg/m2, respectively. The homeostasis model assessment index was 2.7 times greater in the obese subjects. All BTMs, except bone-specific alkaline phophatase, were lower in the obese subjects compared with the controls: the differences at baseline were 40%, 35%, 17%, 31%, and 32% for N-terminal propeptides of type I collagen, cross-linked telopeptides of type I collagen, tartrate-resistant acid phosphatase, total OC, and carboxylated OC (P < .05 for all) after adjusting for whole-body bone area. All BTMs decreased during OGTT. The relative values for the OGTT responses for total, but not for cOC (measured as area under the curve) differed between the two groups (P = .029 and P = .139, respectively): the decrease in total OC during the OGTT was less pronounced in the obese subjects. Responses in other BTMs were similar between the groups. No associations were observed between glucose metabolism and OCs during OGTT with linear regression.

Conclusions:

Bone turnover markers were substantially lower in obese subjects compared with controls. Total OC and cOC showed less pronounced decrease during the OGTT in obese subjects compared with controls, whereas other BTMs responded similarly in the two groups. The role of OC, if anything, in glucose homeostasis is indirect and may be mediated via other factors than glucose or insulin.
Incidence and Risk of Venous Thromboembolism Among Taiwan Osteoporotic Fracture Population under Osteoporosis Pharmacological Treatments
Authors: Lin Tzu-Chieh , Lee Cheng-Han , Yang Chyun-Yu , Yang Yea-Huei Kao , Lin Swu-Jane
Published: March 2014

Context:

There was no clear evidence for the association between oral bisphosphonates or raloxifene and venous thromboembolism (VTE). There might also be ethnic differences in VTE risk.

Objective:

The purpose of this study was to compare the incidence and risk of VTEs for different classes of osteoporosis drugs in the Taiwanese osteoporotic fracture population.

Design:

This was a retrospective cohort study from 2003 to 2007, with up to 6 years follow-up.

Setting:

Enrollees were participants in Taiwan National Health Insurance.

Patients:

Patients older than 50 years who had vertebral or hip fractures and were new to osteoporosis therapy were recruited.

Intervention:

Patients were classified into the alendronate, calcitonin, or raloxifene group according to exposure after follow-up.

Main Outcome Measure:

The primary outcome of our study was all incident VTEs, including deep vein thrombosis and pulmonary embolism. Cox proportional hazard models were used to compare the relative VTE risk among alendronate, raloxifene, and calcitonin groups under an on-treatment scenario.

Results:

There were 25 443, 9642, and 31 900 patients in the alendronate, raloxifene, and calcitonin groups, and the mean age was 74.5 years (SD, 9.6). The incidence of VTE in the alendronate, raloxifene, and calcitonin groups was 11.2, 8.5, and 18.8 per 10 000 person-years. Results from Cox analyses showed that alendronate or raloxifene recipients did not have a higher risk for VTE than calcitonin recipients (adjusted hazard ratio for alendronate, 0.84; 95% confidence interval, 0.47–1.51; adjusted hazard ratio for raloxifene, 0.64; 95% confidence interval, 0.33–1.28).

Conclusion:

This retrospective analysis found that the incidence of VTE in Taiwanese patients with osteoporosis was low, and the risk of VTE was similar across alendronate, raloxifene, and calcitonin recipients in patients with osteoporotic fractures who were new to osteoporosis therapy.
Postcolonial Life and Death: A Process-Based Comparison of Emily Brontë'sWuthering Heightsand Ayu Utami'sSaman
Authors: Tsao Tiffany
Published: March 2014

This comparative study of Wuthering Heights (a mid-nineteenth-century British novel by Emily Brontë) and Saman (a late-twentieth-century Indonesian novel by Ayu Utami) examines the two novels' respective treatments of internal colonization — a shared thematic concern that only becomes apparent with critical attention to the similarities between scenes found in each work. Read together, the two texts expose the limitations that a unilinear model of the colonization process may impose on life for the colonized subject. Whereas Wuthering Heights figures pre-colonial and colonial modes of life as existing on a single chronological continuum, casting the former as an irretrievable thing of the past, Saman conceives of the two co-existing parallel to each other, the former continuing to exist despite the introduction of colonial culture. By proposing and deploying a process-based model of literary comparison that alternately analyzes the similarities and differences between texts rather than attempting to maintain a balanced view of both at once, this essay also hopes to contribute to recent discussions within the field of comparative literature on how to treat textual convergences and divergences.
In vitro and in vivo interactions between Trichoderma viride and Fusarium circinatum
Authors: Martínez-Álvarez Pablo , Alves-Santos Fernando , Diez Julio
Published: March 2014

Fusarium circinatum, a fungus that causes pitch canker disease, has been present in Europe since at least 2003, when it was detected in northern Spain and found to be producing severe damage in tree nurseries and pine plantations. In this study, we tested a method of biological control of the disease with Trichoderma viride, a fungal species successfully used against many other pathogens. In vitro and in vivo assays were carried out to test the efficacy of this antagonist in controlling F. circinatum. The T. viride isolate exerted a significant effect on the growth of F. circinatum in the in vitro assay, reducing the length of the pathogen colony by half. However, although we tested three different concentrations of the T. viride spore solution, no clear conclusions were obtained with regard to the effects on the Pinus radiata seedlings. To our knowledge, this is the first study carried out with the aim of using Trichoderma spp. to control pitch canker disease.
From the Arctic Circle to the Canadian prairies – a case study of silver birch acclimation capacity
Authors: Rousi Matti , Possen Boy , Hagqvist Risto , Thomas Barb
Published: March 2014

Earlier provenance research has indicated poor success even in short distance transfers (> 2â3Â° latitude) of silver birch (Betula pendula Roth) southward from their origin. These results may indicate poor adaptability of silver birch to a warming climate. Some of the scenarios for a warming climate in Finland suggest effective heat sums are likely to double in the north and increase 1.5 fold in the south for the period of 2070â2099. Consequently, the outlook for silver birch appears bleak. To study the acclimation of birch to this projected change we established a provenance trial in northeastern Alberta, Canada, at the temperature area currently predicted for Central Finland (lat. 64â66Â°N) at the turn of this century (1400 dd). Our 10-year experiment showed that all the Finnish provenances (origins 61â67Â°N) have acclimated well to the warmer growth conditions experienced in Alberta at 54Â°N. These results suggest that silver birch has the potential to acclimate to thermal conditions predicted for Finland at the end of the 21st century. Our results also indicate that silver birch has the potential as a plantation species in Canada, where the Finnish birch grew faster in the boreal forest region of Canada than local paper birch (Betula papyrifera Marsh.) provenances.
Chipping operations and efficiency in different operational environments
Authors: Röser Dominik , Mola-Yudego Blas , Prinz Robert , Emer Beatrice , Sikanen Lauri
Published: March 2014

This research analyses the productivity of energy wood chipping operations at several sites in Austria and Finland. The aim of the work is to examine the differences in productivity and the effects of the operational environment for the chipping of bioenergy at the roadside. Furthermore, the study quantifies the effects of different variables such as forest energy assortments, tree species, sieve size and machines on the overall productivity of chipping. The results revealed that there are significant differences in the chipping productivity in Austria and Finland which are largely based on the use of different sieve sizes. Furthermore, the different operational environments in both countries, as well as the characteristics of the raw material also seem to have an effect on productivity. In order to improve the chipping productivity, particularly in Central European conditions, all relevant stakeholders need to work jointly to find solutions that will allow a greater variation of chip size. Furthermore, in the future more consideration has to be given to the close interlinkage between the chipper, crane and grapple. As a result, investments costs can be optimized and operational costs and stress on the machines reduced.
Cross-talk between adipose tissue and the HPA axis in obesity and overt hypercortisolemic states
Authors: Vicennati Valentina , Garelli Silvia , Rinaldi Eleonora , Di Dalmazi Guido , Pagotto Uberto , Pasquali Renato
Published: March 2014

In addition to its roles in providing insulation and mechanical support, adipose tissue (AT) has been recognised as the major site for storage of surplus fuel. Since leptin was discovered, white AT (WAT) has been recognised as an endocrine organ and an important source of biologically active substances with local and/or systemic action called adipokines. The metabolic and endocrine activities of AT are under the control of several hormones: a particular role has been played by glucocorticoids (GC), which able to participate, along with other hormones, both in recruitment of progenitor cells and in differentiation and secretive activities. AT is also able to generate cortisol from cortisone through 11β-hydroxysteroid-dehydrogenase (11β-HSD). There are controversial reports in the literature, showing a hyperactivity of 11β-HSD in obesity. It has been postulated that obesity, particularly the visceral body fat distribution (V-BFD), may be considered a maladaptation to stress exposure, thus leading to hyperactivation of the hypothalamic-pituitary-adrenal (HPA) axis, and higher-than-normal cortisol levels. In this review, we will examine the cross-talk between the HPA axis and AT, their relationship under stressful events, depending on steroid hormones and different adipokine secretions.
A MITE Transposon Insertion Is Associated with Differential Methylation at the Maize Flowering Time QTLVgt1
Authors: Castelletti Sara , Tuberosa Roberto , Pindo Massimo , Salvi Silvio
Published: March 2014

One of the major quantitative trait loci for flowering time in maize, the Vegetative to generative transition 1 (Vgt1) locus, corresponds to an upstream (70 kb) noncoding regulatory element of ZmRap2.7, a repressor of flowering. At Vgt1, a miniature transposon (MITE) insertion into a conserved noncoding sequence was previously found to be highly associated with early flowering in independent studies. Because cytosine methylation is known to be associated with transposons and to influence gene expression, we aimed to investigate how DNA methylation patterns in wild-type and mutant Vgt1 correlate with ZmRap2.7 expression. The methylation state at Vgt1 was assayed in leaf samples of maize inbred and F1 hybrid samples, and at the syntenic region in sorghum. The Vgt1-linked conserved noncoding sequence was very scarcely methylated both in maize and sorghum. However, in the early maize Vgt1 allele, the region immediately flanking the highly methylated MITE insertion was significantly more methylated and showed features of methylation spreading. Allele-specific expression assays revealed that the presence of the MITE and its heavy methylation appear to be linked to altered ZmRap2.7 transcription. Although not providing proof of causative connection, our results associate transposon-linked differential methylation with allelic state and gene expression at a major flowering time quantitative trait locus in maize.
Synthetic cinnamates as potential antimicrobial agents
Authors: Stefanovic Olgica , Radojevic Ivana , Comic Ljiljana
Published: March 2014

This study deals with synthesis of methyl cinnamate, butyl cinnamate, and
p-methoxy methyl cinnamate and testing of their in vitro antimicrobial
activity. Antimicrobial activity was examined towards 29 microorganisms using
microdilution method. It is shown that antimicrobial activity of methyl
cinnamate and p-methoxy methyl cinnamate was better than that of butyl
cinnamate. Sarcina lutea, Bacillus subtilis ATCC 6633, B. subtilis and B.
subtilis IP 5832 (probiotic) were the most sensitive bacteria. It is
established that p-methoxy methyl cinnamate can be a new, potential
anti-Staphylococcus aureus agent with minimum inhibitory concentration of
62.5 ?g/ml. Methyl cinnamate and p-methoxy methyl cinnamate inhibited the
growth of Aspergillus restrictus, A. flavus and A. fumigatus in the
concentration range from 62.5 ?g/ml to 250 ?g/ml.
The sorption of inorganic arsenic on modified sepiolite: Effect of hydrated iron(III)-oxide
Authors: Ilic Nikola , Lazarevic Slavica , Rajakovic-Ognjanovic Vladana , Rajakovic Ljubinka , Janackovic Djordje , Petrovic Rada
Published: March 2014

The sorption of inorganic arsenic species, As(III) and As(V), from water by
sepiolite modified with hydrated iron(III) oxide was investigated at 25 ?C
through batch studies. The influence of the initial pH value, the initial As
concentrations, the contact time and types of water on the sorption capacity
was investigated. Two types of water were used, deionized and groundwater.
The maximal sorption capacity for As(III) from deionized water was observed
at initial and final pH value 7.0, while the bonding of As(V) was observed to
be almost pH independent for pH value in the range from 2.0 to 7.0, and the
significant decrease in the sorption capacity was observed at pH values above
7.0. The sorption capacity at initial pH 7.0 was about 10 mg g?1 for As(III)
and 4.2 mg g?1 for As(V) in deionized water. The capacity in groundwater was
decreased by 40 % for As(III) and by 20 % for As(V). The Langmuir model and
pseudo-second order kinetic model revealed good agreement with the
experimental results. The results show that Fe(III)-modified sepiolite
exhibits significant affinity for arsenic removal and it has a potential for
the application in water purification processes.
Classical Versus Laparoscopic Approach in Retroperitoneal Lesions - Advantages and Limitations
Authors: C Crăciun , L Azamfirei , Mf Coroș , Rc Crăciun
Published: March 2014

Background: At present, the laparoscopic intervention in retroperitoneal primitive tumors, abscesses, haematomas and retroperitoneal effusions is still a challenge. The purpose of this paper is to identify the differences between laparoscopic and conventional surgical interventions in diseases of the retroperitoneum. Material and method: The study follows a retrospective analysis of various retroperitoneal interventions performed on 62 patients between 2010-2012 in the Surgery Clinic 1 of Mures County Hospital. We have chosen from the casuistry the cases with tumoral diseases or nontumoral and divided the patients into two groups: group I who had undergone classic interventions and group II who had undergone laparoscopic procedures. We studied the clinical medical records, surgical protocols and anatomopathological results. Results: For 2010 we extracted 23 cases (39,2% classical interventions), for 2011-21 patients (31,4% classic) and for 2012 -18 cases (29,4% classical interventions). According to the type of the disease, 30 classical interventions were performed for tumoral formations and 21 interventions for non-tumoral formations. Laparoscopic tumoral cases included three tumors and a retroperitoneal metastasis,while the non-tumoral were represented by 7 urohaematic effusions as a result of percutaneous nephrolithotomy procedures. Conclusions: Laparoscopic surgery of retroperitoneal lesions is minimally invasive, the postoperative evolution of patients is favorable, without major complications.. Classical intervention of retroperitoneal lesions is indicated in large haematomas, abscesses, and big invasive tumors with vascular factor which does not allow the use of laparoscopic technique
The Characteristics of Amiodarone-induced Thyrotoxicosis in a Moderate Iodine Deficit Area
Authors: Ancuța-Elena Cota , Oana-Maria Căpraru , Ionela Pașcanu
Published: March 2014

Introduction: Amiodarone (AMI), a class III anti-arrhythmic drug, is associated with a number of side effects, including thyroid dysfunction (both hypo- and hyperthyroidism), which is due to amiodarone's high iodine content and its direct toxic effect on the thyroid. Objective: To evaluate the incidence of Amiodarone induced thyrotoxicosis (AIT) (type, rate of occurrence) and to identify the risk factors involved in its occurrence. Material and method: We examined patients treated with amiodarone, between January 2002 and December 2011, who presented to our Department of Endocrinology Târgu Mures for thyroid dysfunctions. Results: The retrospective study included 87 patients with thyroid dysfunctions; 58 (66.7%) patients had AIT and 29 (33.3%) had Amiodarone induced hypothyroidism (AIH). In the AIT group: 35 were women (60.3%), 23 were men (39.7%); the average age was 61.60 ± 12.39 years. Risk factors identified for the AIT group were male gender (RR = OR = 3.8; Chi-squer = 5.7, p = 0.004) and pre-existing thyroid abnormalities (RR = 2.5, Chi-square = 4.1, p = 0.005). The thyroid dysfunction occurrence was heterogeneous (0.2-183 months). The patients with previous thyroid abnormalities developed earlier thyroid dysfunction compared to those with an apparently normal thyroid gland (22.25 ± 4.14 months versus 32.09 ± 7.69 months, p = 0.02, T test). Conclusion: In the context of the specific iodine geoclimatic intake and the area of origin, amiodarone - induced thyroid dysfunction spectrum is dominated by thyrotoxicosis. Screening and monitoring of thyroid function for patiens under chronic amiodarone treatment is necessary