11 research outputs found
A 2.5MHz bandpass active complex filter With 2.4MHz bandwidth for wireless communications
This paper presents a fully differential 8thorder
transconductor-based active complex filter with
2.4MHz bandwidth and centered at 2.5MHz, designed in
a 90nm 2.5V 7M and MIM capacitors CMOS process
technology. The filter compliants with the requirements
of the IEEE802.15.4 standard. Simulation results
including mismatching and process variations over the
extracted view of the circuit are shown. The filter has a
nominal gain of 12dB, good selectivity (20dB@2MHz
offset), high image rejection (51dB nominal) and low
power consumption (3.6mA @2.5V).Junta de AndalucĂa TIC-927Gobierno de España TEC2007-6807
Biocompatibility, Inflammatory Response, and Recannalization Characteristics of Nonradioactive Resin Microspheres: Histological Findings
Intra-arterial radiotherapy with yttrium-90 microspheres (radioembolization) is a therapeutic procedure exclusively applied to the liver that allows the direct delivery of high-dose radiation to liver tumors, by means of endovascular catheters, selectively placed within the tumor vasculature. The aim of the study was to describe the distribution of spheres within the precapillaries, inflammatory response, and recannalization characteristics after embolization with nonradioactive resin microspheres in the kidney and liver. We performed a partial embolization of the liver and kidney vessels in nine white pigs. The left renal and left hepatic arteries were catheterized and filled with nonradioactive resin microspheres. Embolization was defined as the initiation of near-stasis of blood flow, rather than total occlusion of the vessels. The hepatic circulation was not isolated so that the effects of reflux of microspheres into stomach could be observed. Animals were sacrificed at 48Â h, 4Â weeks, and 8Â weeks, and tissue samples from the kidney, liver, lung, and stomach evaluated. Microscopic evaluation revealed clusters of 10â30 microspheres (15â30Â ÎŒm in diameter) in the small vessels of the kidney (the arciform arteries, vasa recti, and glomerular afferent vessels) and liver. Aggregates were associated with focal ischemia and mild vascular wall damage. Occlusion of the small vessels was associated with a mild perivascular inflammatory reaction. After filling of the left hepatic artery with microspheres, there was some evidence of arteriovenous shunting into the lungs, and one case of cholecystitis and one case of marked gastritis and ulceration at the site of arterial occlusion due to the presence of clusters of microspheres. Beyond 48Â h, microspheres were progressively integrated into the vascular wall by phagocytosis and the lumen recannalized. Eight-week evaluation found that the perivascular inflammatory reaction was mild. Liver cell damage, bile duct injury, and portal space fibrosis were not observed. In conclusion, resin microspheres (15â30Â ÎŒm diameter) trigger virtually no inflammatory response in target tissues (liver and kidney). Clusters rather than individual microspheres were associated with a mild to moderate perivascular inflammatory reaction. There was no evidence of either a prolonged inflammatory reaction or fibrosis in the liver parenchyma following recannalization
The IDENTIFY study: the investigation and detection of urological neoplasia in patients referred with suspected urinary tract cancer - a multicentre observational study
Objective
To evaluate the contemporary prevalence of urinary tract cancer (bladder cancer, upper tract urothelial cancer [UTUC] and renal cancer) in patients referred to secondary care with haematuria, adjusted for established patient risk markers and geographical variation.
Patients and Methods
This was an international multicentre prospective observational study. We included patients aged â„16 years, referred to secondary care with suspected urinary tract cancer. Patients with a known or previous urological malignancy were excluded. We estimated the prevalence of bladder cancer, UTUC, renal cancer and prostate cancer; stratified by age, type of haematuria, sex, and smoking. We used a multivariable mixed-effects logistic regression to adjust cancer prevalence for age, type of haematuria, sex, smoking, hospitals, and countries.
Results
Of the 11 059 patients assessed for eligibility, 10 896 were included from 110 hospitals across 26 countries. The overall adjusted cancer prevalence (n = 2257) was 28.2% (95% confidence interval [CI] 22.3â34.1), bladder cancer (n = 1951) 24.7% (95% CI 19.1â30.2), UTUC (n = 128) 1.14% (95% CI 0.77â1.52), renal cancer (n = 107) 1.05% (95% CI 0.80â1.29), and prostate cancer (n = 124) 1.75% (95% CI 1.32â2.18). The odds ratios for patient risk markers in the model for all cancers were: age 1.04 (95% CI 1.03â1.05; P < 0.001), visible haematuria 3.47 (95% CI 2.90â4.15; P < 0.001), male sex 1.30 (95% CI 1.14â1.50; P < 0.001), and smoking 2.70 (95% CI 2.30â3.18; P < 0.001).
Conclusions
A better understanding of cancer prevalence across an international population is required to inform clinical guidelines. We are the first to report urinary tract cancer prevalence across an international population in patients referred to secondary care, adjusted for patient risk markers and geographical variation. Bladder cancer was the most prevalent disease. Visible haematuria was the strongest predictor for urinary tract cancer
ComparaciĂłn de mĂ©todos de fraccionamiento de formas de oxihidroxidos de Fe y Mn en suelos y productos de sĂntesis
[EN] The fractionation of different iron and manganese forms has been studied by two chemical methods: extraction by a gradient of concentration with HCl and successive extractions with the same extractor (HCl 4N) on a group of synthetic materials from aging in different conditions of iron hydroxide or iron and manganese hydroxide, and on horizons of some soil types.
The result show a good correlation between the two methods for the synthetic products and soils, when both methods separate two or at the most three different components per material. However, the results show a poorer correlation when the materials are more complex. The reasons for the lack of parallelism between both methods and the advantages of each one are discussed.[ES] Se ha estudiado el fraccionamiento de las diversas formas de hierro y manganeso por dos mĂ©todos quĂmicos; extracciĂłn por HCl en gradiente de concentraciĂłn y extracciones sucesivas con un mismo extractante (HCl 4N), sobre un grupo de materiales sintĂ©ticos procedentes de envejecimiento en diversas condiciones de hidrĂłxido de hierro o hidrĂłxidos de hierro y manganeso, perfectamente caracterizados y sobre algunos horizontes de suelos tĂpicos.
Los resultados indican una buena concordancia entre los dos métodos para los productos sintéticos y suelos cuando ambos métodos separan dos o a lo sumo tres componentes distintos por material y una correspondencia menos estrecha cuando los materiales son mås complejos. Se discuten las razones de la falta de paralelismo entre ambos métodos y las ventajes de cada uno.Peer reviewe
Outcomes and features of the inspection of receiver tubes (ITR) system for improved O&M in parabolic trough plants
Concentrated solar power (CSP) plants based on parabolic trough (PT), after several years since their commissioning, demand new operation and maintenance (O&M) developments. Particularly, the receiver tubeÂŽs potential degradation over time is a real challenge. In this paper, the current version of the ITR System's last developments and advanced features are presented together with the main outcomes provided by the system for a real, complete solar field inspection in a commercial PT power plant. Exemplarily, this commercial ITR inspection showed that 0.8% of the tubes were underperforming and thus classified as outliers, while the average relative power of the tubes from the solar field resulted in about 97% of the ideal tubes' power. This paper shows that, thanks to the ITR Inspection System, plant operators can more easily develop and adopt improved O&M strategies, such as corrective and preventive actions in the solar field and even predictive actions in case of periodic inspections