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A new battery charger, based on a multiphase resonant converter, for a high-capacity 48 V LiFePO4 lithium-ion battery is presented. LiFePO4 batteries are among the most widely used today and offer high energy efficiency, high safety performance, very good temperature behavior, and a long cycle life. An accurate control of the charging current is necessary to preserve the battery health. The design of the charger is presented in a tight correlation with a battery model based on experimental data obtained at the laboratory. With the aim of reducing conduction losses, the general analysis of the inverter stage obtained from the parallel connection of N class D LCpCs resonant inverters is carried out. The study provides criteria for proper selection of the transistors and diodes as well as the value of the DC-link voltage. The effect of the leakage inductance of the transformer on the resonant circuit is also evaluated, and a design solution to cancel it is proposed. The output stage is based on a multi-winding current-doubler rectifier. The converter is designed to operate in open-loop operation as an input voltage-dependent current source, but in closed-loop operation, it behaves as a voltage source with an inherent maximum output current limitation, which provides high reliability throughout the whole charging process. The curve of efficiency of the proposed charger exhibits a wide flat zone that includes light load conditions. This work was funded by the Spanish Ministry of Science and the EU through the projects RTI2018-095138-B-C31: “Power Electronics for the Grid and Industry Applications”, TEC2016-80700-R (AEI/FEDER/UE), PID2019-110955RB-I00, and by the Principality of Asturias via Project FC-IDI/2018/000226.

This paper presents the design and modeling of a two-phase resonant converter that drives a LED lamp with a high-frequency pulsed current free of instabilities and flicker efect, fulfilling the recommendations of the IEEE PAR 1789-2015, so that it enables visible light-based communication at a 10 kB/s bit rate. The dynamic study of the converter takes into consideration the efect of the reflected impedance of the output filter on the AC side. In order to evaluate the dynamic response of the converter, a Spice model is defined. A 120 W prototype intended for street lighting applications has been built to validate the analysis and modeling. This work has been sponsored by the Spanish Ministry of Science and Innovation and the EU through the projects CICYT-FEDER-TEC2014-52316-R: “Estimation and Optimal Control for Energy Conversion with Digital Devices, ECOTRENDD” and RTI2018-095138-B-C31: “Power Electronics for the Grid and Industry Applications”.

Objective Anterior cervical discectomy and fusion (ACDF) is an accepted technique for the management of cervical spinal degenerative disease. Recently, new resorbable materials have been proposed for the anterior cervical fusion to eliminate some of the disadvantages and complications of metal plates. The aim of our study was to evaluate the long-term clinical results of the ACDF implants made out of bioabsorbable materials. Methods We performed a retrospective descriptive study of a series of 17 ACDF patients operated with the Inion S-1™ resorbable screws and plates (made out of biodegradable copolymers composed of l -lactic acid and d , l -lactic acid 80/20) 5–7 years ago. The mean age of the patients was 45 years. A single-level procedure was carried out in 13 patients and a double-level procedure in four patients, and the most commonly fused level was C5–C6. Clinical background, preoperative and postoperative symptoms, previous trauma, complications, radiographic fusion and condition of the prevertebral space (preoperative and postoperative) were analyzed. Results We observed a good fusion rate and stability using resorbable plates and screws. None of the patients had associated severe complications such as adjacent tissue edema or infection, or had to be reoperated due to failure or migration of the used implants. Conclusions The results of this retrospective clinical long-term follow up demonstrate that cervical fusion can be successfully achieved using resorbable implants.

This article shows that lamp aging has a significant correlation with flicker generation. In this research work, a test system and a methodology able to measure optical fluctuation produced by different types of lamps and ballast are presented. This experimental platform provides a correlation between voltage flicker levels and optical flicker perception. This platform can be considered as a first step in the definition of new lamp models. The limits of the severity of flicker caused by voltage fluctuations are defined in Europe by the standard CENELEC EN 50160.

A new dc and pulsed dc TIG welding power supply has been designed. Power modules connected in parallel with interleaving operation achieve scalable output current with no reduction of the single module performance and limiting the output current ripple. The resonant converter is supplied by an active rectifier from the AC mains with a reduction of mains current peak by five times.

Aim Fasting plasma glucose (FPG) and the 2-h post-challenge plasma glucose (2hPG) are commonly used to identify those at risk of type 2 diabetes. However, the role of HbA 1c in this prediction has still not been ascertained. Methods The Asturias study is a prospective population-based survey of diabetes and cardiovascular risk factors. Baseline examination, carried out during 1998–1999, involved 1034 individuals, aged 30–75 years, randomly selected to determine the prevalence of type 2 diabetes and prediabetes in the principality of Asturias (northern Spain). In 2004–2005, these same subjects were invited to a follow-up examination, and 700 participated. The present study includes only those who did not have diabetes at baseline. All participants with no known diabetes underwent an OGTT. Baseline HbA 1c levels were measured by HPLC. Results Diabetes had developed in 44 participants at the time of follow-up. Quartiles of baseline HbA 1c values were 3.4–4.8 (Q1), 4.9–5.1 (Q2), 5.2–5.4 (Q3) and 5.5–6.9 (Q4), and the incidence rates of diabetes by quartiles were 1.0 (0.1–7.1), 4.0 (1.5–10.7), 7.9 (4.0–15.9) and 32.6 (22.9–46.4) cases/1000 person-years, respectively. ROC curve analysis comparing HbA 1c , FPG and 2hPG in the prediction of diabetes showed areas under the curve (ROC–AUC) of 0.80 (0.74–0.86), 0.83 (0.77–0.90) and 0.79 (0.72–0.87), respectively. The combination of FPG and HbA 1c had the best predictive performance with an ROC–AUC of 0.88 (0.82–0.93). Conclusion Our study indicates that HbA 1c is strongly predictive of new-onset diabetes in this northern Spanish population, and was similar to FPG and 2hPG in predictive capability. Also, the combined measurement of FPG and HbA 1c improved their individual predictive performance.

This paper presents the analysis and design of a new configuration of a resonant inverter suitable for high-pressure sodium lamp ballast applications. The proposed inverter is the result of the parallel connection of five class D LCsCp resonant inverters. Since the load current is shared among five equal sections, the circuit is able to drive lamps over 1 kW using low-cost power MOSFETs and achieves better efficiency than single class D solutions due to the reduction of the conduction losses. The regulation is implemented at constant frequency, modifying the phase displacement of the output voltage of one inverter section with respect to the others.

This paper quantifies the influence badly parked vehicles and on-street parking maneuvers have on average link journey times as a function of the duration of the events and the number of designated maneuvers and flow, by applying an M/M/∞ queueing model in which arrival and departure are all Poisson processes. The method has been validated using microsimulations calibrated by in-situ measurements taken in the streets of the city of Santander (Cantabria, Spain). The analysis on the delays shows a good fit for the M/M/∞ model for flows of 60–70% of capacity where the error is always lower than 5%. This demonstrates the efficiency of the M/M/∞ model for studying how on-street parking maneuvers and badly parked vehicles influence traffic flow and avoids the need to use generally more laborious microsimulation models. Microsimulations are used to calculate the reduction in link capacity for each case in the study and the increases in average journey times for the rest of the road users. This shows the effect that allowing on-street parking on arterial or main roads has on the rest of the traffic.

This paper proposes a two-stage low-frequency square-wave (LFSW) electronic ballast with digital control. The first stage of the ballast is a power factor correction (PFC) stage, and the second is a full-bridge (FB) converter used for both lamp ignition and LFSW drive. As a novelty for LFSW ballasts, ignition is achieved without an additional igniter circuit by operating the FB during start-up as a high-frequency resonant inverter. After ignition, the converter operates as an LFSW inverter to avoid exciting acoustic resonances by controlling the FB as a buck converter and regulating alternately positive or negative current to the lamp. Lamp power is regulated by adjusting the average current supplied by the PFC stage. Another contribution of this paper is to utilize digital control as a simple solution to achieve multimode control, including resonant lamp ignition, LFSW transitions, and lamp current and power regulation.

This paper presents new design considerations and a control strategy for a two-stage ballast system; power factor correction (PFC) and resonant inverter (RI), for high intensity discharge lamps. The ballast includes a microcontroller whose proposed algorithm implements a power loop and a voltage loop, both to control the PFC, and generates the transistor drive signals of the RI. The power loop adjusts the lamp power in steady state and the voltage loop controls the PFC during the ignition and warm-up time. System stability is studied to verify that the PFC stage provides the ballast with the required stability in long and medium term, while the short term stability is assured by the high output impedance of the LCC inverter, operating in open loop at constant switching frequency. The resulting performance of the ballast shows improvements in ignition repeatability, warm-up time reduction, robustness of the resonant inverter operation, and simple and accurate power control, including dimming operation

This paper presents a simplified envelope model to study the dynamics of a phase-controlled resonant converter suitable to drive light emitting diode (LED) lamps. The approximate closed form of the transfer function is obtained from the proposed reduced-order model. The fast dynamics of the resonant converter allows us implementing a pulsed current source with active control of the on-time-current free of instabilities and flicker effect with a type II or integral-single-lead controller. A 120W prototype intended for street lighting applications has been built to validate the study. This work is sponsored by the Spanish Ministry of Science and the EU through the project CICYT-FEDER- TEC2011- 23612: “Power conversion with new digital control techniques and soft-saturation magnetic cores”.

This paper presents a simplified envelope model to study the dynamics of a phase-controlled resonant converter suitable to drive light emitting diode (LED) lamps. The output current is controlled, at constant switching frequency, through the phase displacement, Ψ, of the control signals of each class D section of the resonant inverter stage. The envelope model of the resonant network is reduced to an equivalent L-C p circuit. The approximate closed form of the transfer function is obtained using the new reduced-order model. The model predicts that the current gain is set by the resonant inverter stage while the bandwidth is mainly defined by the output filter and the LED's dynamic resistance, providing the whole system with excellent dynamic behavior. The fast dynamics of the resonant converter ensures an operation free of instabilities and flicker effect with a simple integral controller. A 120W prototype has been built to validate the study.

This paper presents a resonant converter to drive high-brightness light emitting diode (LED) lamps. The resonant converter operates at constant switching frequency, where the control parameter is the phase displacement ψ between the drive signals of each inverter leg. The proposed driver is able to set different patterns of amplitude and pulsewidth modulation (AM and PWM) of the output current to implement the dimming control of the lamp. This control flexibility arises from the wide bandwidth of the resonant converter ensuring an operation free of instabilities and flicker effects. A 120W prototype intended for street lighting applications has been built to validate the design proposal.

This paper presents the dynamic study of a phase-controlled resonant converter suitable to drive high-brightness light emitting diode (LEDs) lamps. The output current is controlled, at constant switching frequency, through the phase displacement, Ψ, of the control signals of each class D section of the resonant inverter stage. To deal with the study of the transfer function of Ψ to output current, the envelope model of the resonant network is reduced to an equivalent L-R circuit. The approximate closed form of the transfer function is obtained using the new reduced-order envelope model. The model predicts that the current gain is set by the resonant inverter stage. On the other hand, the bandwidth is mainly defined by the output filter and the LEDs' dynamic resistance, providing the whole system with excellent dynamic behavior. A 120W prototype has been built to validate the study.

This chapter provides a review of the evolution of the process of greening the chemical industry. It explains the concept of greening industries, firms and technologies followed by a brief note on business strategy and its relation to “greening”. Next, a historical account on the relation between the chemical industry and the environment is presented. The core part of this chapter is about the different stages of corporate greening evolution in chemicals, ranging from pollution control and prevention, eco-efficiency and corporate environmental responsibility to more radical approaches of sustainable manufacturing and eco-innovation. Finally, a reflection is made upon the challenges this industry has in the view of the most pressing environmental issues of modern industries. A number of cases are used to illustrate the process of greening of this industry in the fields of end-of-pipe technologies, eco-effi ciency best practices, eco-design, and renewable chemicals. A comprehensive list of references of each of the tools and philosophies is also included.

This paper presents the analysis and design of a resonant converter suitable to drive high-brightness power LED lamps for outdoor lighting applications. The inverter stage arises from the parallel connection of two class D LC p C s resonant inverters. The output stage is based on a central tap rectifier without electrolytic capacitor. The output current can be precisely adjusted, at constant switching frequency, trough the phase displacement, Ψ, of the control signals of each class D section. The dimming control follows a PWM pattern whose on-state is set by the nominal phase displacement Ψ and the off-state by setting Ψ at 180° where the output current is cancelled out. Therefore, the average lamp current is modified without necessity of extra switches. The fast dynamics of the resonant stage ensures an operation free of instabilities and flicker effect. A 120W prototype has been built to validate the design proposal.

This paper describes the operation of a learning tool using the Game Based Learning (GBL) methodology. The developed tool, called e-Liza, operates as an activity from the e-learning platform Moodle. E-Liza allows us to pose question-response contests within individual or group games. This tool has been tested in several courses about programming languages undertaken in the Telecommunication Engineering Technical School, University of Valladolid, in the school year 2009-2010. In all the experiments performed, e-Liza has been well-accepted. The percentages of students passing the course who have used e-Liza application exceed the 80%. An important feature of the application is that it allows gathering a great number of statistical data from each student for each topic, showing a wide variety of graphs which can be used by the professor to evaluate the knowledge acquired by the students in any moment, and so, checking the extent of meeting the course objectives.

Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. V. M. López, F. J. Azcondo, F. J. Díaz, and Á. de Castro, "Autotuning digital controller for current sensorless power factor corrector stage in continuous conduction mode", 2010 IEEE 12th Workshop on Control and Modeling for Power Electronics (COMPEL), Boulder (CO), 2010, pp. 1-8, A circuit that compensates the volt-seconds error across the inductor in current sensorless digital control for continuous conduction mode power factor correction (PFC) stage is presented. Low cost ad-hoc sigma-delta analog to digital converters (ΣΔ ADCs) are used to sample the PFC input and output voltage. Instead of being measured, the input current is estimated in a digital circuit to be used in the current loop. A nonlinear carrier control is implemented in the digital controller in order to obtain the power factor correction. Drive signal delays cause differences between the digital current and the real current, producing that volt-seconds error. The control algorithm is compensated taking into account the delays. The influence of a wrong compensation is presented. Experimental results show power factor values and harmonic content within the IEC 61000-3-2 Class C standard in different operation conditions. Furthermore, the use of this PFC stage for electronic ballasts to compensate the effect of the utility voltage fluctuation in HID lamps is also verified taking advantage of the digital device capabilities., This work is sponsored by the Spanish Ministry of Education and Science through the project CICYT-TEC 2008-01753

The IEC has standards covering both a flickermeter and a flicker definition. These documents have been adopted in Europe by the CENELEC as EN norms. The limits of the severity of flicker caused by voltage fluctuations is defined in Europe by the standard CENELEC EN 50160. Under normal operating conditions, flicker level measured according to IEC 61000-4-15 will not exceed the long term severity Plt=1 during 95% of the time in one week. This threshold was originally established considering that a lamp with tungsten coiled coil filament of 60 W and 230 V that is gas-filled produces a flicker perceivable by 50% of the population when it is supplied with a voltage that verifies Plt=1. Other light sources like fluorescent lamps and discharge lamps with ballasts exhibit a different behavior under the same supply conditions. This means that the flickermeter should be different for each type of illumination technique in order to provide accurate information about flicker phenomena. At the same time, lamp age also plays an important role in flicker generation. The above are the main objections given for not adopting the IEC flickermeter in countries as USA. In this research work, a test system and a methodology able to measure the optical fluctuation produced by different types of lamps and ballast is presented. This experimental platform allows to obtain a correlation between voltage flicker levels and optical flicker perception. It can be considered the first step in the definition of new lamp models. This work also shows that age lamp has a significant correlation with flicker generation.

Nowadays, energy efficiency is a hot topic in a very demanding environment. In this way, improvements in lighting applications, which is a significant point of energy consumption, could be very much welcomed. Electronic ballast may serve to this goal since they are focused on achieving energy savings, reduction in the utility line harmonic content and reactive power, as well as on implementing dimming control and some other parameter of interest in lighting applications. On the other hand, power quality problems are very common in our power system and any new electric device should be designed taking into account these events. One of the typical problems in electrical distribution systems are voltage sags. These have a great incidence on the electrical equipment connected to the network in the same area. The sags cause more damages than the rest of disturbances because these have a greater frequency of occurrence. In this work, the effects of voltage sags on several 150-W high- pressure sodium lamps combined with two different types of electronic ballast have been studied. One of the ballasts supplies the required voltage to minimize the reactive component in the resonant inverter, while the other regulates the power supplied by the utility line to be constant in long term, the resonant inverter being also in open loop at constant switching frequency providing the short term stability. The results of these electronic ballasts will be compared with those obtained with the traditional electromagnetic ballast. The influence of the lamp age will be also considered in the approach. The final goal of this study is to improve the performance of the ballast prototypes under voltage sags.

The limits of the severity of flicker caused by voltage fluctuations is defined in Europe by the standard CENELEC EN 50160. Under normal operating conditions, flicker level will not exceed the long term severity Plt=1 during 95% of the time in one week. This threshold was originally established considering that a lamp with tungsten coiled coil filament of 60 W and 230 V that is gas-filled produces a flicker perceivable by 50% of the population when it is supplied with a voltage that verifies Plt=1. Other light sources like fluorescent lamps and discharge lamps with ballasts exhibit a different behavior under the same supply conditions. This means that the flicker meter should be different for each type of illumination technique ir order to provide accurate information about flicker phenomena. At the same time, lamp age also plays an important role in flicker generation. In this research work, a test system and a methodology able to measure the optical fluctuation produced by different types of lamps and ballast is presented. This experimental platform allows to obtain a correlation between voltage flicker levels and optical flicker perception. It can be considered the first step in the definition of new lamp models. This work also shows that age lamp has a significant correlation with flicker generation.

The paper proposes the use of a dsPIC30F2010 for implementing the ignition sequence, a double loop control and selecting the operation modes of a low frequency square wave (LFSW) electronic ballast for two-stage HID lamps. The first stage is the power factor correction (PFC) stage, and the second is a single full-bridge (FB) inverter with LC filter. The latter stage performs function of a resonant circuit for lamp ignition and a current controlled low frequency square wave inverter for normal operation. Ignition is achieved at the resonant frequency of the LC filter when the FB converter is working as a resonant inverter. After ignition the converter operates as a LFSW inverter by controlling the FB to act alternately as a Buck converter supplying positive or negative current. While ignition occurs at the LC filter resonance (f0=25kHz), the Buck converter switching frequency (fsw=200kHz) is selected significantly higher to attenuate high frequency harmonics and avoid exciting acoustic resonance. Lamp stability is achieved by controlling the inductor current of the LC filter, and power mode control is achieved adjusting average current supplied by the PFC stage. The microcontroller selects the different operation modes of the FB converter according to the lamp requirements.

The European standard CENELEC EN 50160 establishes that the severity of flicker caused by voltage fluctuations, under normal operating conditions, will not exceed the long term severity Pu = 1 during 95% of the time in one week. This threshold was originally established considering that a lamp with tungsten coiled coil filament of 60 W and 230 V that is gas- filled produces a flicker perceivable by 50% of the population when it is supplied with a voltage that verifies Pu = 1. Other light sources like fluorescent lamps and discharge lamps with ballasts exhibit a different behavior under the same supply conditions. This means that the flickermeter should be different for each type of illumination technique. A test system and a methodology able to measure the optical fluctuation produced by different types of lamps is presented. This experimental platform allows to obtain a correlation between voltage flicker levels and optical flicker perception. It can be considered the first step in the definition of new lamp models and the specification for new electronic ballast design.

This paper presents the design considerations, control strategy and resulting performance of a two-stage ballast system; power factor correction (PFC) and resonant inverter (RI), for metal halide lamps (MHL). Medium and long term stability, with regard to utility line perturbations and lamp aging, is achieved by the PFC stage controlled in power mode, while the short term stability is assured by the high output impedance of the LCC inverter, operating in open loop at constant switching frequency. Power mode control requires over voltage and short circuit protection. The LCC resonant inverter is designed in such a way that the maximum power supplied to the lamp is inherently limited, provided that the input voltage is also limited. Hence, the protection requirements are reduced to limit only the maximum voltage supplied by the PFC stage to the inverter stage. By boosting the PFC output voltage with respect to the nominal value during the protection mode two benefits are achieved: 1) the ignition performance using the resonance of the LCC circuit is improved, since it is not necessary to reach the highest voltage gain frequency which is more sensitive to frequency or component tolerance. Hot re-ignition performance is also improved since the required voltage gain is also less sensitive to component thermal deviation. 2) The warm-up time is clearly reduced in comparison to electromagnetic ballast or other non-controlled ballast since the RI input voltage increases when the lamp power is below the target value to reach the power level imposed by the reference

The paper proposes the use of a single full-bridge (FB) inverter and LC filter in HID electronic ballast, realizing both the functions of a resonant circuit for lamp ignition and a current controlled low frequency square wave inverter for normal operation. Ignition is achieved by resonance when the converter is controlled as a FB inverter at the resonant frequency of the LC filter. After ignition the converter operates as a LF square wave inverter by controlling the FB to act alternately as a Buck converter supplying positive or negative current. While ignition occurs at the LC filter resonance, the Buck converter switching frequency is selected significantly higher to attenuate high frequency harmonics and avoid exciting acoustic resonances. System stability is achieved by controlling the input current to the FB (output current of the PFC front-end), resulting in a power mode control provided that the voltage supplied by the PFC stage is constant. A digital control circuit selects the different operation modes of the FB converter according to the lamp requirements.

Aims To estimate the prevalence of diabetes mellitus with three diagnostic criteria (WHO-1985 and 1999 and ADA-1997), evaluate their concordance and analyse the sensitivity and specificity of the different screening strategies for diabetes. Methods A cross-sectional population study with two-step sampling. One thousand and 34 people were selected randomly. A 75-g oral glucose tolerance test (OGTT) was performed and venous blood samples were obtained fasting and at 2 h. Results The prevalence of known Type 2 diabetes mellitus (DM-2) is 4%[95% confidence interval (CI) 2.8, 5.1]. By WHO-1985 criteria the prevalence of unknown DM-2 is 5.9% (4.5, 7.4); by ADA-1997 criteria 3.5% (2.5, 4.6) and by WHO-1999 criteria 7.3% (5.8, 8.8). Diagnostic overlap and statistical concordance (coefficient K) are WHO-1985/ADA-1997 29.3%, K = 0.42; WHO-1985/WHO-1999 80%, K = 0.88; ADA-1997/WHO-1999 48%, K = 0.63. If only fasting glucose was used (following ADA-1997), 36.3% of those with diabetes (2-h glucose ≥ 11.1 mmol/l) would be diagnosed. If OGTT was performed (i) in those with a fasting glucose between 6.1 mmol/l and 6.9 mmol/l (9.8% of the population) we would diagnose 66.6%, and (ii) in all those between 5.7 mmol/l and 6.9 mmol/l (18.9% of the population) 81.8% would be diagnosed. Conclusions The ADA criteria decrease the prevalence of DM in the adult population of Asturias by 2.4% and concordance with the classical criteria (WHO-1985) was only 29.3%. Using fasting glucose only (ADA-1997) diagnoses 36.3% of those with diabetes. The recent recommendations of the WHO-1999 increases this to 66.6%. To improve the diagnostic strategy for diabetes and detect up to 81.8% of patients, we propose the use of OGTT for all those with a fasting glucose between 5.7 mmol/l and 6.9 mmol/l.

X-linked retinoschisis (XLRS) is the most common cause of juvenile macular degeneration in males, resulting in vision loss early in life. The gene involved in XLRS was identified recently. It encodes a protein with a disoidin domain, suggested to be involved in cell-cell interactions. We have screened the gene for mutations in 234 familial and sporadic retinoschisis cases and identified 82 different mutations in 214 (91%). Thirty one mutations were found more than once, i.e. 2-10 times, with the exception of the 214G→A mutation which was found in 34 apparently unrelated cases. The origin of the patients, the linkage data and the site of the mutations (mainly CG dinucleotides) indicate that most recurrent mutations had independent origins and thus suggest the existence of a significant new mutation rate in XLRS1. The mutations identified cover the entire spectrum, from small intra-genic deletions (7%), to nonsense (6%), missense (75%), small frameshifting insertions/deletions (6%) and splice site mutations (6%). Since, regardless of the mutation type, no females with a typical RS phenotype were identified, RS seems to be caused by loss-of-function mutations only. Mutations occurred non-randomly, with hotspots at several CG dinudeotides and a C6 stretch. Exons 1-3 contained few, mainly translation-truncating mutations, arguing against an important functional role for this segment of the protein. Exons 4-6, encoding the discoidin domain, contained most, mainly missense mutations. An alignment of 32 discoidin domain proteins was constructed to reveal the consensus sequence and to deduce the functional importance of the missense mutations identified. The mutation analysis revealed a high preponderance of mutations involving or creating cysteine residues, pointing to sites important for the tertiary folding and/or protein function, and highlights several amino acids which may be involved in XLRS1-specific protein-protein interactions. Despite the enormous mutation heterogeneity, patients have relatively uniform clinical manifestations although with great intra-familial variation in age at onset and progression.

Sommario: 1. Premessa. – 2. Italia e Spagna a confronto. – 3. Definizioni. – 4. Italia e Spagna sono “federali” in senso giuridico?. – 5. Federalismo giuridico e federalismo in senso sociologico. – 6. I diritti quali elemento di revisione costituzionale implicita.