(Fegan’s Treatment)

A CAJM article on :Compression Sclerotherapy, a technique also referred to as "Fegan’s Treatment".Over 20 year ago Professor George Fegan introduced a technique developed in Dublin which he termed “compression Sclerotherapy” for the treatment of varicose veins. Professor Fegan (1967) makes the point that only toy rigid adherence to the basic principles involved and with proper attention to the technical detail, can results be obtained which' compare favorably with those of surgery. The detailed anatomical and microscopic studies carried out toy Professor Fegan and his team on the normal structure and micro structures of the veins have emphasized the function of the valves, the structure of the wall and the importance of the nerve supply to the veins. The applied physiology of the veins of the lower limb was correlated with this anatomical study, and the clinical pathology of venous insufficiency then related to normal venous findings

Clinical Features of Kaposi’s Sarcoma Amongst Rhodesian Africans

A CAJM article on the prevalence of a rare type of skin cancer (Kapsosi's Sarcoma) amongst the African population.Kaposi’s sarcoma, a relatively rare malignancy in the Caucasian world has proved to be surprisingly common in certain parts of Africa particularly the Congo, East Africa and Rhodesia. There is still a great deal of mystique surrounding this particular form of malignancy in its origin, in its presentation, and in its treatment. This is probably because even the largest centres in Europe and America have little experience of the condition and it is a relatively new disease to research

Pigmentation of the sole of the foot in Rhodesian Africans

No Abstract

Experiences with Lymphangiography in Rhodesia

A CAJM article on the adaptation of Lymphangiography in Zimbabwe (Rhodesia.)Lymphangiography has really only been attempted in Rhodesia since 1967, but our experience is rapidly growing. For a great many years improvised types of apparatus were used in an attempt to cannulate the vessels. With the introduction of lymphangiographic sets this is no longer necessary and the use of the proper tools makes lymphangiography an easier but still time- consuming procedure

An Investigation Of The Effects Of Inoculated And Intralymphatic Vaccinia Virus On Primary And Secondary Deposits Of Malignant Melanoma

A CAJM investigation of the Effects of Inoculated and Intralymphatic Vaccinia Virus on Primary and Secondary Deposits of Malignant Melanoma.The six patients included in this investigation were selected on the basis of histologically-proven malignant melanomas of the lower extremity, with either local intradermal metastases or regional lymph node involvement. If unvaccinated in the previous five years, vaccination was performed at least 14 days before using the virus therapeutically. Vaccinia virus was prepared from stock vacccine obtained from the South African Institute for Medical Research. Virus was inoculated on the Chorio-allantoic membrane of 12 day embryonated hens’ eggs in which growth was confluent on the third day. Virus was extracted in buffered saline, cleared and tested for sterility. The titre of the undiluted material was 107 pock forming units per ml. This was used at a dilution of 1:50 for both the superficial and deep lesions

Assessing Capacity and Performance of Health Systems Using Principal Component Analysis: Results from Cross Sectional Survey in Kakamega County, Western Kenya

Background: Strong health systems are fundamental if countries are to improve health outcomes and accelerate the attainment of the Sustainable Development Goal (SDGs) number 3 ‘Ensure healthy lives and promote well-being for all at all ages.’ Despite the strong consensus on need to strengthen health systems, many health systems lack the capacity to measure or understand their own weakness and constraints which effectively leaves policy makers without ideas of what they should actually strengthen. Methods: Principal Component Analysis (PCA) was used to factor weights which were used to assess individual contribution of indicators to the health system performance.  PCA is a type of a multivariable linear regression of all indicators in one model. PCA index was classify variables from heighted to the lowest indicator and further used to rank the indicator. Indicators of individual health system building block were weighted independently to measure the amount of contribution to the respective health system building block. The weights were then aggregated to produce individual health system building block indices which were the independent variables in the multivariable linear regression model. Coefficients of the regression was used to assess marginal effects and p-value<0.05 were considered statistics significant result Results: Service delivery (p<0.0001), health financing (p<0.0001), health workforce (p=0.005) and medical supplies and commodities (p<0.0001) had significant effect on service provision. Health governance was not a significant factor influencing service provision. Conclusions: Among the health system building blocks that significantly influenced service provision were service delivery, health workforce, and health financing and medical supplies. This is the first study to the best of the knowledge of the researcher to apply principal component analysis, to analyze health system performance in a devolved system Kakamega. The method provides opportunity for future application in health systems analysis even in absence of comparative data Keywords: Principal Component Analysis, Health Systems DOI: 10.7176/JHMN/59-0

New minimal weight representations for left-to-right window methods

Abstract. For an integer w ≥ 2, a radix 2 representation is called a width-w nonadjacent form (w-NAF, for short) if each nonzero digit is an odd integer with absolute value less than 2 w−1, and of any w consecutive digits, at most one is nonzero. In elliptic curve cryptography, the w-NAF window method is used to efficiently compute nP where n is an integer and P is an elliptic curve point. We introduce a new family of radix 2 representations which use the same digits as the w-NAF but have the advantage that they result in a window method which uses less memory. This memory savings results from the fact that these new representations can be deduced using a very simple left-to-right algorithm. Further, we show that like the w-NAF, these new representations have a minimal number of nonzero digits. 1 Window Methods An operation fundamental to elliptic curve cryptography is scalar multiplication; that is, computing nP for an integer, n, and an elliptic curve point, P. A number of different algorithms have been proposed to perform this operation efficiently (see Ch. 3 of [4] for a recent survey). A variety of these algorithms, known as window methods, use the approach described in Algorithm 1.1. For example, suppose D = {0, 1, 3, 5, 7}. Using this digit set, Algorithm 1.1 first computes and stores P, 3P, 5P and 7P. After a D-radix 2 representation of n is computed its digits are read from left to right by the “for ” loop and nP is computed using doubling and addition operations (and no subtractions). One way to compute a D-radix 2 representation of n is to slide a 3-digit window from right to left across the {0, 1}-radix 2 representation of n (see Section 4). Using negative digits takes advantage of the fact that subtracting an elliptic curve point can be done just as efficiently as adding it. Suppose now that D

Scattering phases in quantum dots: an analysis based on lattice models

The properties of scattering phases in quantum dots are analyzed with the help of lattice models. We first derive the expressions relating the different scattering phases and the dot Green functions. We analyze in detail the Friedel sum rule and discuss the deviation of the phase of the transmission amplitude from the Friedel phase at the zeroes of the transmission. The occurrence of such zeroes is related to the parity of the isolated dot levels. A statistical analysis of the isolated dot wave-functions reveals the absence of significant correlations in the parity for large disorder and the appearance, for weak disorder, of certain dot states which are strongly coupled to the leads. It is shown that large differences in the coupling to the leads give rise to an anomalous charging of the dot levels. A mechanism for the phase lapse observed experimentally based on this property is discussed and illustrated with model calculations.Comment: 18 pages, 9 figures. to appear in Physical Review

Fano Resonances in Electronic Transport through a Single Electron Transistor

We have observed asymmetric Fano resonances in the conductance of a single electron transistor resulting from interference between a resonant and a nonresonant path through the system. The resonant component shows all the features typical of quantum dots, but the origin of the non-resonant path is unclear. A unique feature of this experimental system, compared to others that show Fano line shapes, is that changing the voltages on various gates allows one to alter the interference between the two paths.Comment: 8 pages, 6 figures. Submitted to PR

Rho-Isp Revisited and Basic Stage Mass Estimating for Launch Vehicle Conceptual Sizing Studies

The ideal rocket equation is manipulated to demonstrate the essential link between propellant density and specific impulse as the two primary stage performance drivers for a launch vehicle. This is illustrated by examining volume-limited stages such as first stages and boosters. This proves to be a good approximation for first-order or Phase A vehicle design studies for solid rocket motors and for liquid stages, except when comparing to hydrogen-fueled stages. A next-order mass model is developed that is able to model the mass differences between hydrogen-fueled and other stages. Propellants considered range in density from liquid methane to inhibited red fuming nitric acid. Calculated comparisons are shown for solid rocket boosters, liquid first stages, liquid upper stages, and a balloon-deployed single-stage-to-orbit concept. The derived relationships are ripe for inclusion in a multi-stage design space exploration and optimization algorithm, as well as for single-parameter comparisons such as those shown herein