The role of the discount rate in tendering highway concessions under the LPVR approach.

Flexible-term highway concessions are becoming quite popular around the world as a means of mitigating the traffic risk ultimately allocated to the concessionaire. The most sophisticated mechanism within flexible-term concession approaches is the least present value of the revenues (LPVR). This mechanism consists of awarding the concession to the bidder who offers the least present value of the revenues discounted at a discount rate fixed by the government in the contract. Consequently, the concession will come to an end when the present value of the revenues initially requested has been eventually reached. The aim of this paper is to evaluate the effect that the discount rate established by the government in the bidding terms has on the traffic-risk profile ultimately allocated to the concessionaire. To analyze this effect, a mathematical model is developed in order to obtain the results. I found that the lower the discount rate the larger will be the traffic risk allocated to the concessionaire. Moreover, I found that, if a maximum term is established in the contract, the lower the discount rate, the less skewed towards the downside will be the traffic-risk profile allocated to the concessionair

Imaging Right Iliac Fossa (RIF) pain

Abdominal pain is one of the most common causes for referral to the emergency department coming second only after chest pain. The RIF is the most common location for abdominal pain. Clinical assessment offers little to as aid the diagnosis of RIF pain. With developments in ultrasound (US) and both spiral and multidetector computed tomography (CT), an accurate diagnosis can be made and unnecessary surgery and potentially lethal complications may be avoided.peer-reviewe

From bench to bedside and the problem of ensuring equity in healthcare

As part of its commitment to continuing professional development, the Malta Medical Journal is pleased to issue its clinical updates for this year. The latest developments in the fields of respiratory medicine, gastroenterology, obstetrics and gynaecology, urology, emergency medicine and orthopaedics are presented here. The impact of new technologies in the various fields is a tribute to the scientists who make advances in the diagnosis and management of disease and the clinicians who implement these discoveries. The major hurdle to be overcome in a number of institutions and countries worldwide is lack of access to resources and new management options as a result of inadequate facilities, trained personnel and financial restraints. Arebi & Saunders provide us with an example of the targets attainable with the establishment of a facility dedicated to staff development and training, albeit in this instance, in one particular area.peer-reviewe

Rheumatoid arthritis and spondyloarthropathy

Part 2 of the article can be found through this link: https://www.um.edu.mt/library/oar//handle/123456789/13280Rheumatoid arthritis (RA) and spondyloarthropathy are two groups of inflammatory joint disease. Detection of early inflammatory joint disease is not possible with clinical examination or plain radiography, which have been the main diagnostic methods in the past. Changes detected on plain radiography are those of chronic damage caused by these conditions rather that acute inflammation, which results in delay in diagnosis and often suboptimal outcomes in these patients.peer-reviewe

What is Doppler ultrasound?

The term Doppler should be capitalized because it refers to Christian Johann Doppler, an Austrian physicist (1803–1853). He described a phenomenon whereby the frequency of sound changes when it is reflected off a moving object. If the object is moving towards the observer, reflected sound frequency is increased (blue shift), while if the reflecting object is moving away from the observer, the sound frequency decreases (red shift). This is analogous to a moving ambulance with its siren on; the siren pitch increases as ambulance approaches and decreases as it receeds. The Doppler Effect may be used also in ultrasound. With normal grey scale ultrasound we rely on amplitude of reflected sound waves and the reflectivity of anatomic structures is proportional to the intensity (or amplitude) of the reflected sound and hence brightness on the scanner display. If frequency (rather than amplitude) is analysed, one can detect motion on the basis of Doppler shifts. These frequency shifts can be quantified reasonably accurately according to direction, velocity and also acceleration, all of which provide specific signatures that help identify both normal and diseased blood vessels.peer-reviewe

Medical education and healthcare needs

Educators in the sphere of medicine face a number of complex challenges in the provision of a learning environment suited to ensuring students acquire essential core competencies as well as additional skills and expertise targeted to their area of practice This needs to be done against a series of standards in medical curricula for quality assurance purposes. Furthermore, in medicine, the concept of life long learning is essential to the further honing of available skills and the acquisition of new expertise relevant to the ever-changing and increasing demands on medical practitioners. Mobility of graduates and doctors has highlighted this, as moving to a different geographical area invariably causes a change in the working environment, the medical problems encountered and the resources available to deal with these issues.peer-reviewe

Ductal carcinoma in situ (DCIS)

Ductal carcinoma in situ (DC IS) is a breast malignancy that is characterized by the proliferation of malignant ductal epithelial cells without evidence of invasion through the basement membrane. The incidence of DCIS has risen 11-fold between 1081 and 2001 through improved detection rates with screening mammography. DCIS is not a single entity but a spectrum of disease ranging from low to high grade. DCIS grade is an important prognostic factor with high grade lesions being more likely to recur.peer-reviewe

Medicine : the way ahead

The significant developments in medicine which have taken place over the years have no doubt been a determining factor in improving the Maltese medical profession. Hi-technology has in many areas taken over in both the diagnostic as well as in the curative field. In this article the author mentions the developments in new technologies introduced in the Maltese hospitals, besides the major growing interest in the academic field.peer-reviewe

Endometrial imaging

The endometrium demonstrates a wide spectrum of normal and pathologic appearances throughout menarche as well as during the prepubertal and postmenopausal years and the first trimester of pregnancy. Characteristic morphologic changes take place in the uterus and endometrium over time.peer-reviewe

Navigating through archives, libraries and museums: Topic Maps as a harmonizing instrument

The paper deals with the possibility of creating a topic map based system where different sectors of cultural heritage would interact with users, by monitoring the navigation histories of users and the statistics on the searches, in order to authorize variant form of names. The problem of managing different sectors and harmonizing them both from a structural and a semantic view point, by using Topic Maps, is also discussed. With regards to this, we are introducing two projects, which are largely based on the above mention use of Topic Maps. The original publication is available at www.springerlink.com http://www.springerlink.com/content/6k5473124678k452/fulltext.pd