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Este libro radica en la necesidad de ofrecer a los profesionales de la salud, especialmente a los cirujanos y residentes en formación, una herramienta de consulta y aprendizaje práctico, actualizada y de fácil acceso adultos en todas las etapas de la vida.

Introduction and objectives In Spain, 0.3% of patients with hypertension are refractory to conventional treatment. The complications resulting from deficient control of this condition can lead to poor quality of life for the patient and considerable health care costs. Barostim is an implantable device designed to lower blood pressure in these patients. The aim of this study was to analyze the cost-effectiveness of Barostim compared with drug therapy in hypertensive patients refractory to conventional treatment (at least 3 antihypertensive drugs, including 1 diuretic agent). Methods We used a Markov model adapted to the epidemiology of the Spanish population to simulate the natural history of a cohort of patients with refractory hypertension over their lifetime. Data on the effectiveness of the treatments studied were obtained from the literature, and data on costs were taken from hospital administrative databases and official sources. Deterministic and probabilistic sensitivity analyses were conducted. Results Barostim increased the number of quality-adjusted life years by 0.78 and reduced the number of hypertension-associated clinical events. The incremental cost-effectiveness ratio in a cohort of men reached 68 726 euros per year of quality-adjusted life. One of the main elements that makes this technology costly is the need for battery replacement. The results were robust. Conclusions Barostim is not a cost-effective strategy for the treatment of refractory hypertension in Spain. The cost-effectiveness ratio could be improved by future reductions in the cost of the battery.

Resumen Introduccion y objetivos En Espana, el 0,3% de los pacientes hipertensos son refractarios al tratamiento convencional. Las complicaciones derivadas de un control deficiente se traducen en mala calidad de vida para el paciente y un coste importante para el sistema sanitario. Barostim es un dispositivo implantable que busca reducir la presion arterial de estos pacientes. El objetivo del presente estudio es analizar el coste-efectividad de Barostim comparado con terapia farmacologica en pacientes hipertensos refractarios al tratamiento convencional (al menos tres farmacos antihipertensivos, siendo uno de ellos un diuretico). Metodos Modelo de Markov adaptado a la epidemiologia de la poblacion espanola que simula la historia natural de una cohorte de pacientes con hipertension arterial refractaria a lo largo de su vida. Los datos sobre efectividad de los tratamientos se obtuvieron de la literatura y los de costes, de bases de datos administrativas hospitalarias y de fuentes oficiales. Se realizaron analisis de sensibilidad deterministico y probabilistico. Resultados Barostim redujo los eventos clinicos asociados a la hipertension y aumento en 0,78 el numero de anos de vida ajustados por calidad. El cociente de coste-efectividad incremental para una cohorte de varones alcanzo los 68.726 euros por ano de vida ajustado por calidad. Uno de los principales elementos que encarece la tecnologia es el coste del recambio de la bateria. Los resultados fueron robustos. Conclusiones Barostim no es una estrategia coste-efectiva para el tratamiento de la hipertension refractaria en Espana. Reducciones futuras en el precio de la bateria mejorarian su cociente de coste-efectividad.

17 pags., 12 figs., Continuous, real-time monitoring of surface seismic activity around the globe is of great interest for acquiring new insight into global tomography analyses and for recognition of seismic patterns leading to potentially hazardous situations. The already-existing telecommunication fiber optic network arises as an ideal solution for this application, owing to its ubiquity and the capacity of optical fibers to perform distributed, highly sensitive monitoring of vibrations at relatively low cost (ultra-high density of point sensors available with minimal deployment of new equipment). This perspective article discusses early approaches on the application of fiber-optic distributed acoustic sensors (DASs) for seismic activity monitoring. The benefits and potential impact of DAS technology in these kinds of applications are here illustrated with new experimental results on teleseism monitoring based on a specific approach: the so-called chirped-pulse DAS. This technology offers promising prospects for the field of seismic tomography due to its appealing properties in terms of simplicity, consistent sensitivity across sensing channels, and robustness. Furthermore, we also report on several signal processing techniques readily applicable to chirped-pulse DAS recordings for extracting relevant seismic information from ambient acoustic noise. The outcome presented here may serve as a foundation for a novel conception for ubiquitous seismic monitoring with minimal investment., This work was supported by the project FINESSE, Grant No. MSCA-ITN-ETN-722509; the DOMINO Water JPI project under the WaterWorks2014 cofounded call by EC Horizon 2020 and Spanish MINECO; the Comunidad de Madrid and FEDER Program under Grant No. SINFOTON2-CM: P2018/NMT-4326; the Spanish Government under Project Nos. TEC2015-71127-C2-2-R, RTI2018- 097957-B-C31, and RTI2018-097957-B-C33. M.R.F.M. and H.F.M. acknowledge financial support from the Spanish MICINN under Contract Nos. FJCI-2016-27881 and IJCI-2017-33856, respectively. M.A.S. acknowledges AC3E Basal Project No. FB0008 and thanks “Becas Iberoamérica Santander Universidades Convocatoria 2018” for supporting his research stay at the Universidad de Alcalá, Spain.

Sedentarism, overweight and malnutrition generate an increase in the production of reactive oxygen species leading to a state of chronic oxidative stress. In patients with type 2 diabetes mellitus, oxidative stress alters pancreatic insulin secretion and the actions of the hormone on target cells, contributing to the development of micro and macrovascular complications. During physical exertion a state of transient oxidative stress occurs. As a consequence, the organism generates multiple physiological adaptations to these repetitive stimuli. Physical exercise is beneficial for type 2 diabetes mellitus but there is a paucity of information about the effects of physical exercise on biomarkers of oxidative stress in patients with the disease. We herein try to elucidate if the effects of exercise on oxidative stress can help in the prevention and treatment of type 2 diabetes mellitus and which is the most effective modality of physical exercise to reduce oxidative stress markers.

Sedentarism, overweight and malnutrition generate an increase in the production of reactive oxygen species leading to a state of chronic oxidative stress. In patients with type 2 diabetes mellitus, oxidative stress alters pancreatic insulin secretion and the actions of the hormone on target cells, contributing to the development of micro and macrovascular complications. During physical exertion a state of transient oxidative stress occurs. As a consequence, the organism generates multiple physiological adaptations to these repetitive stimuli. Physical exercise is beneficial for type 2 diabetes mellitus but there is a paucity of information about the effects of physical exercise on biomarkers of oxidative stress in patients with the disease. We herein try to elucidate if the effects of exercise on oxidative stress can help in the prevention and treatment of type 2 diabetes mellitus and which is the most effective modality of physical exercise to reduce oxidative stress markers.

HTA is very well known by hospital doctors and managers in Spain, due to the long tradition of national/regional HTA Spanish agencies. Nevertheless, HB-HTA is still in its early phases. The assessment of health technologies (specifically medical devices, capital equipment, diagnostic tests and procedures) is very heterogeneous among hospitals, ranging from non existing approaches to methodologically robust procedures. The latter are representative of the raise of HB-HTA in Spain. In this chapter, the experience from three Spanish hospitals (two high-tech hospitals and one community hospital) in organizing and performing HB-HTA is described. Since differences in context exist among hospitals, HB-HTA is differently organized and performed. The impacts of these experiences are also presented as well as are the challenges and the natural future evolution of HB-HTA in Spain.

Seasonal influenza causes significant morbidity and mortality and has a substantial economic impact on the healthcare system. The main objective of this study was to compare the cost per patient for a rapid commercial PCR assay (Xpert® Flu) with an in-house real-time PCR test for detecting influenza virus. Community patients with influenza like-illness attending the Emergency Department (ED) as well as hospitalized patients in the Hospital Clínic of Barcelona were included. Costs were evaluated from the perspective of the hospital considering the use of resources directly related to influenza testing and treatment. For the purpose of this study, 366 and 691 patients were tested in 2013 and 2014, respectively. The Xpert® Flu test reduced the mean waiting time for patients in the ED by 9.1 hours and decreased the mean isolation time of hospitalized patients by 23.7 hours. This was associated with a 103€ (or about $113) reduction in the cost per patient tested in the ED and 64€ ($70) per hospitalized patient. Sensitivity analyses showed that Xpert® Flu is likely to be cost-saving in hospitals with different contexts and prices.

Objetivo: Evaluar los resultados alejados de la valvuloplastía mitral percutánea (VMP), y analizar los factores asociados con eventos y reestenosis tardía. Métodos y resultados: De 252 VPM realizadas entre diciembre de 1987 y diciembre de 2006, 245 pacientes tuvieron un mínimo de 6 meses de seguimiento y evaluación ecocardiográfica antes y después del procedimiento (97%). La edad media fue de 46,3 ± 11,37 años, las mujeres fueron 83,6%. La media de seguimiento fue de 35,25 ± 28,84 meses, rango 6-132. La muerte cardiovascular, y el reemplazo de la válvula mitral o una segunda VMP fueron considerados como marcadores de peor resultado. El área de la válvula mitral aumentó de 1,0 ± 0,17 cm2 a 1,71 ± 0,31 cm2 (p 8 (p = 0,03). Cinco pacientes fallecieron (2,04%), 22 (8,9%) requirieron reemplazo de la válvula mitral y 11 (4,5%) una segunda VMP. No encontramos variables clínicas o ecocardiográficas capaces de predecir estos eventos. Conclusiones La VMP tuvo una tasa aceptable de complicaciones atribuibles al procedimiento. Las características ecocardiográficas de la válvula mitral se correlacionaron con la reestenosis. La incidencia de eventos tardíos es baja.

Recent studies have analysed the impact of capital account opening on income growth, implicitly assuming that the various forms of foreign savings have similar effects. In fact, theoretical considerations suggest that the individual components of private capital inflows have different effects on growth. This paper analyses the link between income growth and private capital inflows. It presents system GMM estimates with annual observations from 1985 to 1996 for 72 countries. When full-sample results are checked for country and period changes, most of capital inflow series lose their ability to explain income growth. Bank flows stand as the sole source of foreign financing that displays a positive and robust correlation with growth.

Various optical techniques were used to investigate relevant parameters involved in photodynamic therapy (PDT) of human basal cell carcinomas (BCCs). The aim of the study was to compare the diagnostic and therapeutic outcome when using topically applied methyl-esterified delta -aminolevulinic acid (ALA-ME) and delta -aminolevulinic acid (ALA). A total of 35 pathologically verified BCCs in 14 patients were investigated. A diode laser. emitting continuous light at 633 nm, was used to induce PDT. The diagnostic measurements were performed before, during, and after PDT. Laser-induced fluorescence (LIF) was used to monitor the build-up of the ALA/ALA-ME-induced protoporphyrin IX (PpIX), The superficial tissue perfusion was measured with laser-Doppler perfusion imaging (LDPI) and the temperature of the lesion and the surrounding tissue was imaged with an IR-camera. A clear demarcation between the lesion and the normal skin was detected with LIF before the treatment for both PpIX precursors. The fluorescence measurements suggest that PpIX builds up to a higher degree and more selectively in the tumour following ALA-ME as compared to ALA. The LDPI measurements indicate a local transient restriction in blood perfusion immediately post-PDT. The measurement with the IR-camera revealed a temperature rise of about 1-2 degreesC during the treatment. (Less)

Selective capital controls tax only some components of capital flows. One of the rationales for such controls is that they increase the scope for an independent monetary policy, without taxing foreign direct investment and other long term flows. The first part of this paper offers a new framework to evaluate how selective capital controls might increase monetary autonomy, which considers two types of capital flows that coexist: the taxed and exempt flows. It is found that under free floating selective controls increase monetary autonomy, in the sense of allowing the authorities to set the path of the nominal exchange rate. But under predetermined exchange rate rules, the contribution of selective controls to monetary autonomy depends of the ability to reduce total inflows, which is an empirical matter. The second part describes the Chilean unremunerated reserve requirement (URR), a selective control introduced in June 1991 on a permanent basis, in a setting of predetermined exchange rates. This control collected substantial revenue, proving that it was relevant. An econometric model with data for 1987–1996 finds that substitution from the exempt short-term flows compensated reductions in taxed short-term flows, so the Chilean URR did not discourage total net short-term credit inflows to the private sector. This implies that the Chilean URR failed to contribute to monetary autonomy.

El cáncer renal es más común en hombres que se encuentran entre la sexta y séptima década de vida y sólo el 9% de los casos se presenta inicialmente con la tríada clásica (hematuria, dolor y masa en flanco). En la mayoría de los casos se trata de un hallazgo incidental. Entre los factores de riesgo más relevantes están descritos el tabaquismo, la hipertensión arterial, la obesidad, la exposición a sustancias químicas como el cadmio, asbesto e hidrocarburos. El cáncer renal se presenta en el 17% de pacientes como enfermedad metastásica. Entre los sitios más frecuentes para metástasis se encuentran: pulmón, ganglios, hueso, cerebro, hígado y glándulas suprarrenales. Las metástasis cutáneas de origen renal se presentan en aproximadamente el 4.6%. Presentamos el caso de un paciente cuya primera manifestación clínica de un carcinoma renal de células claras fue una lesión cutánea a nivel nasal.

This paper analyzes an unremunerated reserve requirement on cross-border short term credit inflows, as applied in Chile. The impact of this reserve requirement over the path of the real exchange rate is investigated empirically. The authorities expected t

El cáncer renal representa el 3% de los tumores del adulto, su incidencia ha aumentado hasta un 30% en la última década, la bilateralidad es del 2%. La nefrectomía radical es considerada el manejo ideal del cáncer renal. Los buenos resultados obtenidos con la resección parcial, hacen considerar a la cirugía conservadora como el mejor tratamiento en los casos de tumores renales bilaterales. Asimismo se evita la diálisis, minimizando el riesgo subsiguiente de déficit inmunológico y alteración en la calidad de vida. En la actualidad existe controversia en cuanto a la técnica quirúrgica a realizar: resección parcial vs. nefrectomia radical. Presentamos el caso de una mujer de 61 años con cáncer renal bilateral. Se planificó cirugía radical de riñón derecho por gran tumoración, nefrectomía parcial y conservación de nefrona en el riñón izquierdo. Mientras se realizaban exámenes preoperatorios presentó una tromboembolia pulmonar y falleció.

Aid for fighting infectious and parasitic diseases has had a statistically significant role in the under-five mortality reduction in the last decade. Point estimates indicate a country average reduction of 1.4 deaths per thousand under fives live-born attributable to aid at its average level in 2000-2010. The effect would be an average drop of 3.3 in the under-five mortality rate at the aid levels of 2010. By components, a dollar per capita spent in fighting malaria has caused the largest average impact, statistically higher than a dollar per capita spent in STD/HIV control. We do not find statistically significant effects of other infectious disease aid, including aid for the control of tuberculosis.

The Millennium Declaration (2000) set as one of its targets a substantial reduction in child mortality. This paper studies whether the massive increase in development aid can account for part of the reduction in child mortality observed in developing countries since the year 2000. To do so, we analyze a panel of more than 130 developing countries over the 2000-2008 period. We use the time trend evolution of aid to identify an exogenous source of variation. Total aid has had no statistically significant effect on child mortality. However, a disaggregate analysis identifies certain sectors of aid that have had a significant impact. The effects have been larger in high mortality countries, including Sub-Saharan Africa. Projections based on our estimates strongly support the concern that most countries in that region will miss the Millennium Goals target on child mortality.

Properties of GMM estimators for panel data, which have become very popular in the empirical economic growth literature, are not well known when the number of individuals is small. This paper analyses through Monte Carlo simulations the properties of various GMM and other estimators when the number of individuals is the one typically available in country growth studies. It is found that, provided that some persistency is present in the series, the system GMM estimator has a lower bias and higher efficiency than all the other estimators analysed, including the standard first-differences GMM estimator.

Colposcopy is a primary diagnostic method used to detect cancer and precancerous lesions of the uterine cervix. During the examination, the metaplastic and abnormal tissues exhibit different degrees of whiteness (acetowhitening effect) after applying a 3%–5% acetic acid solution. Colposcopists evaluate the color and density of the acetowhite tissue to assess the severity of lesions for the purpose of diagnosis, telemedicine, and annotation. However, the color and illumination of the colposcopic images vary with the light sources, the instruments and camera settings, as well as the clinical environments. This makes assessment of the color information very challenging even for an expert. In terms of developing a Computer-Aided Diagnosis (CAD) system for colposcopy, these variations affect the performance of the feature extraction algorithm for the acetowhite color. Non-uniform illumination from the light source is also an obstacle for detecting acetowhite regions, lesion margins, and anatomic features. There fore, in digital colposcopy, it is critical to map the color appearance of the images taken with different colposcopes into one standard color space with normalized illumination. This paper presents a novel image calibration technique for colposcopic images. First, a specially designed calibration unit is mounted on the colposcope to acquire daily calibration data prior to performing subject examinations. The calibration routine is fast, automated, accurate and reliable. We then use our illumination correction algorithm and a color calibration algorithm to calibrate the exam data. In this paper we describe these techniques and demonstrate their applications in clinical studies.

Optical pulse coding is successfully applied to long-range sensors based on Brillouin optical time domain analysis, achieving a record of 1 meter spatial resolution over 50 km of SMF with 2.2°C / 44microstrain temperature/strain resolutions.

Endoscopic images suffer from a fundamental spatial distortion due to the wide angle design of the endoscope lens. This barrel-type distortion is an obstacle for subsequent Computer Aided Diagnosis (CAD) algorithms and should be corrected. Various methods and research models for the barrel-type distortion correction have been proposed and studied. For industrial applications, a stable, robust method with high accuracy is required to calibrate the different types of endoscopes in an easy of use way. The correction area shall be large enough to cover all the regions that the physicians need to see. In this paper, we present our endoscope distortion correction procedure which includes data acquisition, distortion center estimation, distortion coefficients calculation, and look-up table (LUT) generation. We investigate different polynomial models used for modeling the distortion and propose a new one which provides correction results with better visual quality. The method has been verified with four types of colonoscopes. The correction procedure is currently being applied on human subject data and the coefficients are being utilized in a subsequent 3D reconstruction project of colon.

Since the late 1990s, the UNDP Office of Development Studies has raised awareness among the development and donor communities that the enhanced provision of international public goods will be of critical importance to achieving the Millennium Development Goals (MDGs),1 notably the objectives of reducing poverty (Kaul et al. 1999). The UN conference on Financing for Development held in Monterrey, Mexico, in March 2002 has challenged the donor community to put in place the means and the structures required to mobilize the finance needed to support these goals, which, among others, stipulate the reduction of world poverty by half by the year 2015. Available evidence (Dyer and Beynon 2003) suggests that the impact of investing in international public goods can be high and is important for achieving the MDGs. For example, the cost of lifting one person out of income poverty through agricultural research and global trade expansion is estimated to be much lower than the cost of the same impact through aid to poor countries.

Empirical studies find that changes in schooling are not correlated with changes in per capita income. Similarly, the estimation in levels also produces minor coefficients for years of schooling. Low social returns and measurement error in educational variables have been invoked as possible explanations for such findings. This paper shows that collinearity between physical and human capital stocks seriously undermines the ability of educational indicators to display significance in panel data estimates. On top of that, failure to cope with endogeneity has produced biased estimates. As opposed to the earlier empirical literature, the social return on schooling is positive and significant, but no Lucas-type externalities are observed. Finally, the quality of education emerges as a significant determinant of heterogeneity in social returns across countries.

Fluorescence spectroscopy is one of many optical methods that are potentially clinically useful for noninvasive detection and characterization of disorders on the cervical part of uterus, including precancerous lesions. The cervix uteri exhibits a biologically complex tissue and the morphology of a biopsy is generally not homogenous. The standard histopathological protocol accounts only for the most severe condition found within the biopsy and no information is given on other constituents potentially influencing the recorded fluorescence spectra. Spectra are usually correlated, using multivariate techniques, to the histopathological diagnosis of the biopsies. Since the probe volume of fluorescence spectroscopy is considerably smaller than the extension of the biopsy, this can cause problems in the search for correlation between the fluorescence signals and the pathological structures. In addition, the orientation and location of the biopsies are normally not recorded. We now report on the first detailed histopathological protocol where numerous tissue parameters, such as thickness and type of the epithelium and the number of blood vessels, glands, and inflammatory cells, are tabulated and the orientation and location of the biopsy are recorded as precisely as possible. Hopefully, the use of this protocol together with sophisticated mathematical methods will increase the probability to classify cervical disorders of the uterus, including precancerous lesions, with high sensitivity and specificity.

To overcome the limited treatment depth of superficial photodynamic therapy we investigate interstitial light delivery. In the present work the treatment light was delivered using a system in which three or six clear-cut fibers were placed in direct contact with the tumor area. This placement was thought to represent a step toward general purpose interstitial PDT. Twelve nodular basal cell carcinomas were treated employing delta-aminolevulinic acid and 635 nm laser irradiation. Fluorescence measurements were performed monitoring the buildup and subsequent bleaching of the produced sensitizer protoporphyrin IX. The treatment efficacy, judged at a 28-month follow-up, showed a 100% complete response. Two punch excisions at 7 months converted two partial responses to complete responses. One patient failed to appear at all follow-up sessions. The outcome of the treatments was comparable to superficial photodynamic therapy in terms of histological, clinical, and cosmetic results.

Colposcopy is a primary diagnostic method used to detect cancer and precancerous lesions of the uterine cervix. During the examination, the metaplastic and abnormal tissues exhibit different degrees of whiteness (acetowhitening effect) after applying a 3%-5% acetic acid solution. Colposcopists evaluate the color and density of the acetowhite tissue to assess the severity of lesions for the purpose of diagnosis, telemedicine, and annotation. However, the color and illumination of the colposcopic images vary with the light sources, the instruments and camera settings, as well as the clinical environments. This makes assessment of the color information very challenging even for an expert. In terms of developing a Computer-Aided Diagnosis (CAD) system for colposcopy, these variations affect the performance of the feature extraction algorithm for the acetowhite color. Non-uniform illumination from the light source is also an obstacle for detecting acetowhite regions, lesion margins and anatomic features. Therefore, in digital colposcopy, it is critical to map the color appearance of the images taken with different colposcopes into one standard color space with normalized illumination. This paper presents a novel image calibration technique for colposcopic images. First, a specially designed calibration unit is mounted on the colposcope to acquire daily calibration data prior to performing patient examinations. The calibration routine is fast, automated, accurate and reliable. We then use our illumination correction algorithm and a color calibration algorithm to calibrate the patient data. In this paper we describe these techniques and demonstrate their applications in clinical studies.

A system for interstitial photodynamic therapy is used in the treatment of thick skin tumors. The system allows simultaneous measurements of light fluence rate, sensitizer fluorescence, and tissue oxygen saturation by using the same fibers as for therapeutic light delivery. Results from ten tumor treatments using delta-aminolevulinic acid (ALA)-induced protoporphyrin IX show a significant, treatment-induced increase in tissue absorption at the therapeutic wavelength, and rapid sensitizer photobleaching. The changes in oxy- and deoxyhemoglobin content are monitored by means of near-infrared spectroscopy, revealing a varying tissue oxygenation and significant changes in blood volume during treatment. These changes are consistent with the temporal profiles of the light fluence rate at the therapeutic wavelength actually measured. We therefore propose the observed absorption increase to be due to treatment-induced deoxygenation in combination with changes in blood concentration within the treated volume. A higher rate of initial photobleaching is found to correlate with a less pronounced increase in tissue absorption. Based on the measured signals, we propose how real-time treatment supervision and feedback can be implemented. Simultaneous study of the fluence rate, sensitizer fluorescence, and local tissue oxygen saturation level may contribute to the understanding of the threshold dose for photodynamic therapy. (c) 2006 Society of Photo-Optical Instrumentation Engineers.

A system for interstitial photodynamic therapy with delta-aminolaevulinic acid and multiple optical fibers has been developed. The system enables photodynamic treatment of large embedded tumor volumes and utilizes real-time measurements to allow on-line dosimetry. Important parameters such as light fluence rate, sensitizer fluorescence intensity, and changes in local blood oxygen saturation are measured with the same fibers that deliver the therapeutic light. Data from the first clinical treatments on nodular basal cell carcinomas indicate a major treatment-induced light absorption increase, rapid sensitizer photo-bleaching, and a relatively constant global tissue oxygen saturation level during the treatment.

We attempt to explain why standard explanations of the poverty of nations are unsatisfactory. We first argue that human capital is low in poor countries because its production has increasing returns with respect to life expectancy. We then show that the reason why capital does not flow to poor countries (the Lucas paradox) can readily be explained once market prices rather than PPP prices are used to assess the return to physical capital: the return to capital in poor countries is not higher than in the rich world in spite of its relative scarcity. We finally argue that PPP calculations bias downwards the measured TFP of poor countries, which may in part explain their lower productivity. The message of hope is that education can shoot up as life expectancy increases. A higher level of human capital would appreciate the real exchange rate through a Balassa-Samuelson effect, thus raising the profitability physical capital. This in turn would encourage foreign capital to flow to developing countries

An interactive system for interstitial PDT using Δ-aminolevulinic acid and multiple fibres for light delivery has been developed. Interactive control is achieved by measuring light fluence distribution, sensitizer concentration and oxygenation level throughout the tissue.

The present level of ODA falls short of the amount needed to finance the Millennium Development Goals (MDGs). The figure of additional $50 billion per year, roughly the present total of ODA spent by DAC donors, is often quoted (e.g. by the Zedillo Report); it results from the sum of the fight against communicable diseases ($ 7-10 billion), primary schooling ($10 billion), infant and maternal mortality ($12 billion) and halving world poverty ($20 billion). The scarcity of public resources raises the importance of investing in international public goods as the cost of lifting one person out of income poverty, for example through agricultural research and global trade expansion, is estimated to be much lower than the cost of the same impact through traditional aid to poor countries. This raises important issues for donor strategies, in particular principles of aid allocation, which this paper aims to address. First, should aid be partly earmarked towards international public goods? ...

To develop PDT beyond treatment of thin superficial tumors, to also be an efficient treatment alternative to deeply located and/or thick tumors, a system based on interstitial illumination using multiple fibers has been developed. Conditions that could benefit from such a treatment modality are for instance malignant brain tumors and tumors in the oral cavity. In interstitial PDT one needs to use multiple fibers for light delivery in order to allow treatments of tumors larger than a few millimeters in diameter. Our sytem consists of a laser light source, a beam-splitting system dividing the light into three or six output fibers and a custom-made dosimetry program. The concept is then to use these fibers not only for delivering the treatment light, but also to measure parameters of interest for the treatment outcome. The fluence rate of the light emitted by each fiber is measured at the positions of the other fiber tips. From these results the light dose at all positions could be recalculated. Changes in optical properties as well as bleaching and concentration of the photosensitizer during the treatment could be monitored and compensated for in the dosimetry. Tumors have been treated both in experimental studies and in patients with thick superficial Basal Cell Carcinomas. Almost all treated skin lesions responded with complete response.

An imaging spectrograph, designed and built by Science and Technology International (STI), and a point monitoring system, developed at the Lund Institute of Technology, have been used to measure the fluorescence and reflectance of cervical tissue in vivo . The instruments have been employed in a clinical trial in Vilnius, Lithuania, where 111 patients were examined. Patients were initially screened by Pap smear, examined by colposcopy and a tissue sampling procedure was performed. Detailed histopathological assessments were performed on the biopsies, and these assessments were correlated with spectra and images. The results of the spectroscopic investigations are illustrated by a thorough discussion of a case study for one of the patients, suggesting that the techniques are useful in the management of cervical malignancies.

A hyperspectral imaging spectrograph has been used to measure the fluorescence and reflectance of cervical tissue in vivo. The instrument was employed in a clinical trial in Vilnius, Lithuania, where 111 patients were examined. The patients were initially screened by Pap smear, examined by colposcopy and a tissue sampling procedure was performed. Detailed histopathological assessments were performed on the biopsies, and these assessments were correlated with spectra and images. The results of the spectroscopic investigations show that different tissue types within one biopsy region exhibit different spectral signatures. A spectral analysis of the entire image localizes dysplastic regions in both fluorescence and reflectance, suggesting that the hyperspectral imaging technique is useful in the management of cervical malignancies.

A novel photodynamic therapy system based on interstitial illumination using multiple fibres is under development. The aim with this system is to enable treatment of large tumour volumes and also to utilise real-time measurements to allow on-line dosimetry. Important dosimetric parameters to measure are light fluence rate, sensitizer fluorescence intensity and local blood oxygenation. A construction which allows all functions to be readily performed with a single system is presented. We believe that interstitial PDT utilising this technique may be attractive in many clinical situations.

The use of fluorescence and reflectance spectroscopy in the analysis of cervical histopathology is a growing field of research. The majority of this research is performed with point-like probes. Typically, clinicians select probe sites visually, collecting a handful of spectral samples. An exception to this methodology is the Hyperspectral Diagnostic Imaging (HSDI®) instrument developed by Science and Technology International. This non-invasive device collects contiguous hyperspectral images across the entire cervical portio. The high spatial and spectral resolution of the HSDI instruments make them uniquely well suited for addressing the issues of coupled spatial and spectral variability of tissues in vivo. Analysis of HSDI data indicates that tissue spectra vary from point to point, even within histopathologically homogeneous regions. This spectral variability exhibits both random and patterned components, implying that point monitoring may be susceptible to significant sources of noise and clutter inherent in the tissue. We have analyzed HSDI images from clinical CIN (cervical intraepithelial neoplasia) patients to quantify the spatial variability of fluorescence and reflectance spectra. This analysis shows the spatial structure of images to be fractal in nature, in both intensity and spectrum. These fractal tissue textures will limit the performance of any point-monitoring technology.

This paper studies the puzzling lack of correlation between income and schooling in macro regressions. It is argued that the root of the puzzle is threefold. First, there is a problem of a proper definition of the way in which years of schooling should enter into a production function. Second, collinearity between physical and human capital stocks seriously undermines the ability of educational indicators to display any significance in growth regressions. Third, failure to cope with measurement error and endogeneity produces biased estimates. After dealing with these problems, the neoclassical approach to human capital is strongly supported by the data ...

The paper attempts to explain why single factor explanations of the poverty of nations are usually found to be unsatisfactory. Middle- and low-income countries excluding sub-Saharan Africa, for instance, have an income per head which stands at about one third of the rich countries’ income per head. Yet each of the three items of the Solow model, namely human capital, physical capital (appropriated weighted) and total factor productivity, are each equal to about 70 per cent of the corresponding levels of rich countries. But 70 per cent to the power of three is 35 per cent! Multiplying small or relatively benign handicaps can yield dramatic effects on a country’s income. The paper then moves on to explain each of the three items. It argues that the Lucas paradox on why capital is scarce can readily be solved, once market prices rather than PPP prices are used to assess the return to capital mobility, and on the same ground it argues that PPP calculations bias downwards the TFP of ...

A system for the photodynamic laser treatment of massive tumors that employs multiple optical fibers to be inserted into the tumor mass is described. The light flux through the tumor can be assessed by use of the individual fibers both as transmitters and as receivers. With a computer model that describes the diffusive light propagation, optical dosimetry is under development. The system has been tested in an experimental animal tumor model in preparation for clinical work. Currently, delta-aminolevulinic acid is used as a sensitizer, activated by 635-nm radiation from a 2.0-W compact diode laser system. With the availability of future, highly selective drugs absorbing approximately 750 nm, larger tumor volumes should be treatable, and surrounding, sensitive normal tissue should be spared.

El trabajo tuvo como propósito develar el estado en torno a la integración de TIC en la formación de estudiantes de las carreras de pedagogía de la Universidad de Los Lagos en los campus de Osorno y Puerto Montt de Chile. Para la recopilación de la información se utilizó la técnica de investigación documental, a través de la cual se analizan las mallas curriculares y los programas de estudio que son implementados en la formación de TIC en educación. Los resultados nos revelan que existen situaciones muy dispares en la formación en esta área, la que se expresa en diferencias significativas en la cantidad de horas designadas entre las carreras de ambos Campus. Además, según los estándares TIC para docentes en Chile, los estudiantes tendrían un alto porcentaje de horas de trabajo en la dimensión pedagógica, no así en la dimensión de gestión. Después del análisis realizado se propone una serie de medidas, entre las que se considera incorporar el trabajo con TIC al interior de las didácticas de la especialidad y en los procesos de prácticas, además de desarrollar instrumentos para medir el manejo de TIC tanto al ingreso como al finalizar el proceso formativo.Conocimiento Educactivo, Vol. 1, 2014: 11-33

We present a new data set for years of schooling across countries for the 1960-2000 period. The series are constructed from the OECD database on edu- cational attainment and from surveys published by UNESCO. Two features that improve the quality of our data with respect to other series, particularly for series in first-differences, are the use of surveys based on uniform classification systems of education over time, and an intensified use of information by age groups. As a result of the improvement in quality, these new series can be used as a direct substitute for Barro and Lee's (2001; Oxford Economic Papers, 3, 541-563) data in empirical research. In standard cross-country growth regressions we find that our series yield significant coefficients for schooling. In panel data estimates our series are also sig- nificant even when the regressions account for the accumulation of physical capital. Moreover, the estimated macro return is consistent with those reported in labour studies. These results differ from the typical findings of the earlier literature and are a consequence of the reduction in measurement error in the series.