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En cardiología nuclear, el diagnóstico de infección e inflamación cardiovascular mediante PET/TC con [18F]FDG es de interés creciente, ya que esta técnica ha mejorado la certeza diagnóstica en pacientes con endocarditis infecciosa en prótesis valvulares respecto a la ecocardiografía, en pacientes con dispositivos intracardíacos, cuya frecuencia de implantación va en aumento debido al progresivo envejecimiento de la población, así como en aquellos con sospecha de vasculitis de grandes vasos. Son situaciones clínicas graves, en las que es necesario establecer lo antes posible el diagnóstico correcto y el tratamiento adecuado, pues pueden producir complicaciones severas, alta mortalidad, además de elevados costes hospitalarios. Se realiza una revisión del uso de la exploración PET/TC con [18F]FDG en la infección e inflamación cardiovascular, incluyendo el punto de vista clínico y la aportación de otras técnicas de imagen, centrándose en las condiciones para la adecuada realización de esta exploración, preparación del paciente, obtención de imágenes, su interpretación correcta y posibilidades de cuantificación, detallando las características específicas del diagnóstico en los pacientes con prótesis valvulares, dispositivos intracardíacos y vasculitis de grandes vasos, tanto inicialmente como durante el seguimiento, para valorar la respuesta al tratamiento. Se analizan las posibles causas de resultados falsos positivos y falsos negativos, y se destaca la especial importancia en estos casos de la colaboración multidisciplinar para obtener la máxima rentabilidad diagnóstica. In Nuclear Cardiology, the diagnosis of cardiovascular infection and inflammation by [18F]FDG PET/CT is of growing interest, because this technique has improved the certainty in the diagnosis of infective endocarditis in patients with prosthetic valves respect to echocardiography, in patients with cardiac implantable devices, with increasing frequency of implantation because of the progressive ageing of the population, as well as in patients with suspected large vessel vasculitis. They are serious clinical situations, where it is necessary to establish as soon as possible the correct diagnosis and appropriate treatment, because they can cause severe complications, high mortality and also increased health care costs. We review the use of [18F]FDG PET/CT in cardiovascular infection and inflammation, including the clinical point of view and the contribution of other image modalities, focusing on the conditions for the appropriate methodology of this exploration, patient preparation, images acquisition, their correct interpretation and the quantification possibilities, defining the specific characteristics of the diagnosis in patients with prosthetic valves, cardiac implantable devices and large vessel vasculitis, in initial diagnosis as well as in the follow-up, to assess the treatment response. We analyze the possible causes of false positive and false negative results and we emphasize the special value in these cases of a multidisciplinary team for optimal management of patients. [ABSTRACT FROM AUTHOR]

This paper deals with weighted G-Drazin inverses, which is a new class of matrices introduced to extend (to the rectangular case) G-Drazin inverses recently considered by Wang and Liu for square matrices. First, we define and characterize weighted G-Drazin inverses. Next, we consider a new pre-order defined on complex rectangular matrices based on weighted G-Drazin inverses. Finally, we characterize this pre-order and relate it to the minus partial order and to the weighted Drazin pre-order. [ABSTRACT FROM AUTHOR]

The MOD21 Land Surface Temperature and Emissivity (LST&E) product will be included in forthcoming Moderate Resolution Imaging Spectroradiometer (MODIS) Collection 6. Surface temperature and emissivities for thermal bands 29 (8.55 μm), 31 (11 μm) and 32 (12 μm) will be retrieved using the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Temperature and Emissivity Separation (TES) method adapted to MODIS at-sensor spectral radiances, previously corrected with the Water Vapor Scaling method (MOD21 algorithm). We simulated MOD21 product estimates over two different sandy deserts (i.e. White Sands and Great Sands) using a series of MODIS scenes from 2010 to 2013. The objective of this study was to evaluate the anisotropy of the thermal infrared emissivity over semiarid regions, since angular variations of thermal infrared emissivity imply important uncertainties in satellite LST retrievals. The obtained LSEs and their dependence on zenith viewing angles were analyzed. Results from the MOD21 simulated algorithm showed that band 29 LSE decreased up to 0.038 from nadir to zenith angle of 60°, while LSEs for bands 31 and 32 did not show significant variation. MOD21 LSE for band 29 also showed mean differences between night and daytime retrievals of + 0.027 for WS and + 0.009 for GS. These differences can be attributed to the water vapor adsorption of the soil from the atmosphere. MOD21 nadir and off-nadir LSEs showed a good agreement with laboratory emissivity measurements, and were used to validate with satellite data a zenithal-dependent emissivity model proposed in a previous study. [ABSTRACT FROM AUTHOR]

In this paper seasonal epidemiological processes are considered and a strategy of periodic vaccination is proposed. The invariant formulations associated with an N-periodic system and the reproduction numbers associated with them are considered. A collection of measures to study the stability of the system is introduced. Moreover, the collection of s-basic reproduction number at time j help us to establish conditions on the periodic vaccination rates in the vaccination program. Finally, an SIR model is showed and a comparison between the results obtained using constant or periodic vaccination program is analyzed. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, numerical methods for the solution of linear singular differential system are analysed. The numerical solution of initial value problems by means of a finite difference approach and a possible implementation of the Drazin inverse vector product is discussed. Examples of index 1 and index 2 differential algebraic equations have been studied numerically. [Copyright &y& Elsevier]

Using the group inverse, an explicit solution to a symmetric singular system is described. The general explicit solution is derived when the symmetric singular system satisfies the regularity condition. Certain special properties of these singular systems are presented. Finally, a symmetric balanced realization is obtained from an equivalent standard control system. [Copyright &y& Elsevier]

In this paper, the minus matrix partial order is considered to introduce the concept of minus partial ordered control systems. The transmission of the reachability property under this binary relation is investigated. Furthermore, the analysis of compartmental systems leads us to consider block triangular matrices. Hence, the existence and computation of partially ordered matrices having a similar block structure are studied. These results are applied to compartmental systems to get, via feedback, related systems with the same block structure and ordered under the minus partial order. [ABSTRACT FROM AUTHOR]

The toxicity of 34 environmental samples from potentially polluted and reference stations were evaluated by means of the AMPHITOX test from acute to chronic exposure according to the toxicity found in each sample. The samples were obtained from surface and ground water, leaches, industrial effluents and soils. The data, expressed in acute, short-term chronic and chronic Toxicity Units (TUa, TUstc and TUc) resulted in a maximal value of 1000 TUc, found in a leach, while the lower toxicity value was 1.4 TUa corresponding to two surface water samples. In five samples (four providing from reference places) no toxicity was detected. The results point out the possibility of evaluating the toxicity of a wide diversity of samples by means of AMPHITOX as a customized toxicity test. The fact that almost all samples with suspected toxicity in rivers and streams from the Metropolitan area of Buenos Aires city resulted toxic, indicates the need of enhanced stewardship of chemical substances for environmental and human health protection purposes. [ABSTRACT FROM AUTHOR]

Bufo arenarum embryos at the end of their embryonic development wereacclimated to cadmium (Cd) by means of a 10-day treatment protocol. Embryos were processed for metallothionein (Mt) isolation and Cd and zinc (Zn) contents were measured. The results showed that: (1) the uptake of Cd in the experimental embryos was 7 mu g/g embryo (wet weight) representing a bioaccumulation of Cd 255 times higher than in the maintaining medium; (2) a major Mt-like fraction was Cd-induced 7.8 times that in control embryos; two other protein fractions also bound Cd and Zn but were induced by Cd only about 2 and 1.4 times; (3) the Zn concentration was about 44 mu g Zn/g embryo (wet weight) and did not change significantly (p greater than 0.01) in the experimental embryos with respect to controls, but in acclimated embryos the essential metal was released from the Mts. The enhanced Mt synthesis and release of Zn from the native Mts are discussed in relation to the acclimation phenomenon. [ABSTRACT FROM AUTHOR]

Bufo arenarum females were treated daily with 0.5 mg Cd kg-1 during 10 days to evaluate the uptake of this heavy metal and theinduction of metallothionein synthesis in the liver. The liver incorporated 26% of the Cd administered, about 6.5 times higher than the average uptake of the other tissues of B. arenarum. Three protein fractions from the B. arenarum liver bound Cd, and were induced by this xenobiotic up to approx. 24 times above the basal level of these proteins. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To know the contraceptive use and trends in the Spanish female population. Study design: Since 1997, we have conducted a survey every 2 years on the use of contraceptive methods among a representative sample of Spanish women of childbearing potential (15–49 years). Results: In the period 1997–2003, the percentage of use of contraceptive methods in Spain rose from 55.6% to 71.2%. The most commonly used method was the condom (21% in 1997, 21.9% in 1999, 29.5% in 2001 and 35.7% in 2003), followed by the contraceptive pill (14.2%, 16.5%, 19.2% and 18.3%, respectively). Male or female sterilization remained stable with percentages of use of 5–7%. IUDs are used by about 5% of women. Conclusions: The use of contraceptive methods among Spanish women of childbearing potential generally fits quite well the patterns found in other developed countries, and we observed a trend towards increased use of effective methods. [Copyright &y& Elsevier]

Introduction/Background In the treatment of severe scoliosis, pre-surgical halo-gravity traction (HGT) achieves an increase in curve flexibility and in preoperative pulmonary function as well as a neurologic risk reduction following final surgery. Our aim was to describe the benefits and complications of HGT in adolescents with idiopathic scoliosis or secondary scoliosis while awaiting vertebral fusion. Material and method A descriptive and retrospective study. Sixteen patients admitted to hospital and carrying a HGT between January 2014 and December 2017 were included. The main judgment criteria were the height gain, the final weight of traction, the decrease in the Cobb angle, the gain in the forced vital capacity (FVC) and the description of complications. Results There were eight teenagers with an idiopathic scoliosis aged-mean (SD) 12.1(1.9) years old, a height gain of 7.6(2.3)cm, a final weight of traction of 13.7(3.9)kg corresponding to 37.2(7.5)% of body weight. Cobb angle mean(SD) of 97.5(8)° was reduced of 26.9(11.1)° at the end of traction. And a FVC gain mean (SD) of 12.4(8.8)%. Likewise, eight adolescents with a secondary scoliosis aged-mean(SD) 12.8(1.2) years old, a height gain of 9.2(2.8)cm, a final weight of traction of 12.7(1.3)kg corresponding to 38.9(11.6)% of body weight. Cobb angle mean(SD) of 100(13.8)° was reduced of 26.5(8.4)° at the end of traction. And a FVC gain mean(SD) of 7.1(9.7)%. The most frequent complications in the group of idiopathic scoliosis ( n = 8) were neck pain (75%), headache (37.5%), pin pain (25%), visual disorders, thorax pain and pin infection (12.5%). In the group of secondary scoliosis ( n = 8), neck pain (100%), headache (62.5%), back pain (50%), pin pain and anxiety (25%), neurological disorders and pin infection (12.5%). Conclusion HGT was in general well tolerated and should be considered before vertebral fusion to improve spinal flexibility and respiratory function in idiopathic or secondary scoliosis. [ABSTRACT FROM AUTHOR]