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X-ray ray tracing is used to develop ion-temperature corrections for the analysis of the X-ray Imaging Crystal Spectrometer (XICS) used at Wendelstein 7-X (W7-X) and perform verification on the analysis methods. The XICS is a powerful diagnostic able to measure ion-temperature, electron-temperature, plasma flow, and impurity charge state densities. While these systems are relatively simple in design, accurate characterization of the instrumental response and validation of analysis techniques are difficult to perform experimentally due to the requirement of extended x-ray sources. For this reason, a ray tracing model has been developed that allows characterization of the spectrometer and verification of the analysis methods while fully considering the real geometry of the XICS system and W7-X plasma. Through the use of ray tracing, several important corrections have been found that must be accounted for in order to accurately reconstruct the ion-temperature profiles. The sources of these corrections are described along with their effect on the analyzed profiles. The implemented corrections stem from three effects: (1) effect of sub-pixel intensity distribution during de-curving and spatial binning, (2) effect of sub-pixel intensity distribution during forward model evaluation and generation of residuals, and (3) effect of defocus and spherical aberrations on the instrumental response. Possible improvements to the forward model and analysis procedures are explored, along with a discussion of trade-offs in terms of computational complexity. Finally, the accuracy of the tomographic inversion technique in stellarator geometry is investigated, providing for the first time a verification exercise for inversion accuracy in stellarator geometry and a complete XICS analysis tool-chain.
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This paper reports on the design and the performance of the recently upgraded X-ray imaging spectrometer systems, X-ray imaging crystal spectrometer and high resolution X-ray imaging spectrometer, installed at the optimized stellarator Wendelstein 7-X. High resolution spectra of highly ionized, He-like Si, Ar, Ti, and Fe as well as H-like Ar have been observed. A cross comparison of ion and electron temperature profiles derived from a spectral fit and tomographic inversion of Ar and Fe spectra shows a reasonable match with both the spectrometers. The also measured impurity density profiles of Ar and Fe have peaked densities at radial positions that are in qualitative agreement with the expectations from the He-like impurity fractional abundances, given the measured temperature profiles. Repeated measurements of impurity decay times have been demonstrated with an accuracy of 1 ms via injection of non-recycling Ti, Fe, and Mo impurities using a laser blow-off system.
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An in situ wavelength calibration system for the X-ray Imaging Crystal Spectrometer (XICS) on W7-X has been developed to provide routine calibration between plasma shots. XICS is able to determine plasma flow profiles by measuring the Doppler shift of x-ray line emission from highly charged impurity species. A novel design is described that uses an x-ray tube with a cadmium anode placed in front of the diffracting spherically bent crystal. This arrangement provides calibration lines over the full detector extent for both the Ar16+ and Ar17+/Fe24+ spectrometer channels. This calibration system can provide a relative wavelength accuracy of 3 × 10-7 Å across the full spatial extent of the detector, which corresponds to 50 m/s in the W7-X system. An absolute wavelength calibration of 1 × 10-5 Å is expected, corresponding to 1 km/s, based on the current known accuracy of the calibration wavelength and the achievable measurement of the absolute positioning of the hardware. This calibration system can be used to independently calibrate XICS systems on both stellarators and tokamaks, without the need for special plasma conditions often used for calibration, such as locked modes on tokamaks. Experimental and simulated results are shown along with expected results, and the complete design of the calibration hardware that is to be installed in the W7-X XICS system.
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A new Thomson scattering system using standard commercially available components has been designed for the non-axisymmetric plasmas of the Compact Toroidal Hybrid (CTH). The beam, generated by a frequency doubled Continuum PL DLS 2 J Nd:YAG laser, is passed vertically through an entrance Brewster window and an aperturing baffle system to minimize the stray laser light that could enter the collection optics. The beam line has been designed with an 8 m propagation distance to the mid-plane of the CTH device with the beam diameter kept less than 3 mm inside the plasma volume. The beam exits the vacuum system through another Brewster window and enters a beam dump, again to minimize the stray light in the vacuum chamber. Light collection, spectral processing, and signal detection are accomplished with an f/#â¼ 1 aspheric lens, a commercially available Holospec f/1.8 spectrometer, and an Andor iStar DH740-18U-C3 image intensified camera. Spectral rejection of stray laser light, if needed, can be performed with the use of an optional interference filter at the spectrometer input. The system has been developed for initial single point measurements of plasmas with core electron temperatures of approximately 20-300 eV and densities of 5 × 10(18) to 5 × 10(19) m(-3) dependent upon operational scenario.
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Objetivo: La obstrucción de la salida de la vejiga con síntomas obstructivos e irritativos es una posible complicación de la cirugía para la incontinencia urinaria femenina. Cuando los síntomas persisten el tratamiento es quirúrgico, y por lo general consiste en una uretrolisis precisa. La vía de acceso suele ser transvaginal. En este documento proponemos y describimos nuestra experiencia con una aproximación transvestibular. Material y métodos: A 18 mujeres que fueron sometidas a una cirugía anti-incontinencia (12 con TVT, tres con TOT y tres con colposuspensión retropúbica de Burch) y que presentaban síntomas de obstrucción o de irritación se les realizó una uretrolisis transvestibular. Cinco pacientes tenían retención urinaria y las demás tenían una orina residual postvaciamiento mayor a 100ml. Con una hoja de bisturí se realizó una incisión alrededor del meato y la uretra fue progresivamente liberada, disecando justo por debajo del hueso púbico hacia arriba y en la pared vaginal hacia abajo, desvinculándola bajo visión directa para obtener una liberación circular completa de la uretra. Al final el meato uretral se vuelve a poner en su posición con puntos circulares. Resultados: La operación dura entre 20 y 40 minutos. Se dejó un catéter urinario durante 24-48 horas y no se observó complicación alguna. El volumen residual postmiccional disminuyó en todos los casos y se redujeron los síntomas irritativos. Conclusiones: La vía transvestibular es un enfoque seguro y efectivo para realizar la uretrolisis, independientemente del tipo de cirugía contra la incontinencia que se lleve a cabo. La uretrolisis tiene la ventaja de trabajar en un tejido relativamente intacto, permite una desconexión completa de la uretra incluso en el espacio retropúbico y mantiene la pared vaginal intacta (AU)
Objective: Bladder outlet obstruction with obstructive and irritative urinary symptoms may be a complication of surgery for female urinary incontinence. In presence of persistent symptoms, the therapy is surgical and usually consists in an accurate urethrolysis. The way of approach is generally transvaginal. In this paper we propose and describe our experience with a transvestibular approach. Material and methods: 18 women who had undergone anti-incontinence surgery (TVT 12 pts, TOT 3 pts, Burch retropubic colposuspension 3 pts) with obstruction and/or irritative symptoms underwent to a transvestibular urethrolysys. Five patients had urinary retention and the rest of patients had post voiding residual urine>100ml. Using a scalpel blade a circum-meatal incision was performed and the urethra was progressively freed, dissecting just below the os pubis upwards and on the vaginal wall downwards, untethering it under direct vision in order to abtain a complete circular freeing of the urethra. In the end, the urethral meatus is repositioned with circular stiches. Results: The operation lasts between 20 and 40minutes. An urethral catheter was left in place for 24-48hours and no complications were observed. The post-voiding residual urine decreased in all of the cases and the irritative symptoms were reduced. Conclusions: The transvestibular approach for urethrolysis is safe and effective regardless of the previous anti-incontinence surgery carried out. This procedure has the advantage of working in a relatively unscarred tissue, allows for a complete untethering of the urethra even in the retropubic space and leaves the vaginal wall intact (AU)
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Humanos , Femenino , Procedimientos Quirúrgicos Urogenitales/efectos adversos , Procedimientos Quirúrgicos Urogenitales/métodos , Incontinencia Urinaria/terapia , Cabestrillo Suburetral , Uretra/cirugía , Enfermedades de la Vejiga Urinaria/cirugíaRESUMEN
Introduction. The recurrence of urethral/bladder neck stricture after multiple endoscopic procedures is a rare complication that can follow prostatic surgery and its treatment is still controversial. Material and Methods. We retrospectively analyzed our data on 17 patients, operated between September 2001 and January 2010, who presented severe urinary incontinence and urethral/bladder neck stricture after prostatic surgery and failure of at least four conservative endoscopic treatments. Six patients underwent a transperineal urethrovesical anastomosis and 11 patients a combined transperineal suprapubical (endoscopic) urethrovesical anastomosis. After six months the patients that presented complete incontinence and no urethral stricture underwent the implantation of an artificial urethral sphincter (AUS). Results. After six months 16 patients were completely incontinent and presented a patent, stable lumen, so that they underwent an AUS implantation. With a mean followup of 50.5 months, 14 patients are perfectly continent with no postvoid residual urine. Conclusions. Two-stage procedures are safe techniques to treat these challenging cases. In our opinion, these cases could be managed with a transperineal approach in patients who present a perfect operative field; on the contrary, in more difficult cases, it would be preferable to use the other technique, with a combined transperineal suprapubical access, to perform a pull-through procedure.
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OBJECTIVE: Bladder outlet obstruction with obstructive and irritative urinary symptoms may be a complication of surgery for female urinary incontinence. In presence of persistent symptoms, the therapy is surgical and usually consists in an accurate urethrolysis. The way of approach is generally transvaginal. In this paper we propose and describe our experience with a transvestibular approach. MATERIAL AND METHODS: 18 women who had undergone anti-incontinence surgery (TVT 12 pts, TOT 3 pts, Burch retropubic colposuspension 3 pts) with obstruction and/or irritative symptoms underwent to a transvestibular urethrolysys. Five patients had urinary retention and the rest of patients had post voiding residual urine>100 ml. Using a scalpel blade a circum-meatal incision was performed and the urethra was progressively freed, dissecting just below the os pubis upwards and on the vaginal wall downwards, untethering it under direct vision in order to abtain a complete circular freeing of the urethra. In the end, the urethral meatus is repositioned with circular stiches. RESULTS: The operation lasts between 20 and 40 minutes. An urethral catheter was left in place for 24-48 hours and no complications were observed. The post-voiding residual urine decreased in all of the cases and the irritative symptoms were reduced. CONCLUSIONS: The transvestibular approach for urethrolysis is safe and effective regardless of the previous anti-incontinence surgery carried out. This procedure has the advantage of working in a relatively unscarred tissue, allows for a complete untethering of the urethra even in the retropubic space and leaves the vaginal wall intact.
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Complicaciones Posoperatorias/cirugía , Uretra/cirugía , Obstrucción del Cuello de la Vejiga Urinaria/cirugía , Femenino , Humanos , Incontinencia Urinaria/cirugía , Procedimientos Quirúrgicos Urológicos/métodosRESUMEN
Investigaciones previas en madres adolescentes en contextos de pobreza han evidenciado dificultades de estas jóvenes en el vínculo con sus bebés y en su rol materno. Estos resultados fueron la motivación para llevar a cabo una investigación acción basada en una intervención grupal para promover un vínculo saludable de las madres con sus bebés en una zona de extrema pobreza de Lima (Perú). El artículo presenta una sistematización y discusión del material verbal que emergió durante las sesiones grupales el cual se ha estructurado en torno a tres temas centrales: el rol que cumplió el grupo como continente, la construcción de una identidad materna versus una identidad adolescente y el reconocimiento del rol materno en el contexto de pobreza. El cuidado emocional en la prevención del dolor posquirúrgico en niños y adolescentes
Previous research on adolescent mothers in contexts of poverty in the city of Lima (Peru) had shown evidence of the difficulties these young mothers encounter in their bonding with their babies and with their maternity role. These results were the motivation to carry on an action research, based on a group intervention to promote a healthy bonding between these mothers and their babies in a context of extreme poverty in Lima. This paper presents a systematization and discussion of the verbal material that emerged in the sessions. The material has been structured in relation to three axes: The role that the group played as a container, the construction of a maternal identity versus an adolescent identity and the acknowledgement of a maternal role in a context of poverty (AU)
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Humanos , Femenino , Adolescente , Relaciones Madre-Hijo/psicología , Embarazo en Adolescencia/psicología , Conducta del Adolescente , Pobreza/psicología , Factores Socioeconómicos , Evaluación de Eficacia-Efectividad de IntervencionesRESUMEN
BACKGROUND: Previous multivariate analysis performed between April 1, 1994, and December 31, 2000 from the Organ Procurement Transplant Network/United Network for Organ Sharing (OPTN/UNOS) database has shown that kidneys from black donors were associated with lower graft survival. We compared graft and patient survival of different kidney donor-to-recipient ethnic combinations to see if this result still holds on a recent cohort of US kidney transplants. METHODS: We included 72,495 recipients of deceased and living donor kidney alone transplants from 2001 to 2005. A multivariate Cox regression method was used to analyze the effect of donor-recipient ethnicity on graft and patient survival within 5 years of transplant, and to adjust for the effect of other donor, recipient, and transplant characteristics. Results are presented as hazard ratios (HR) with the 95% confidence limit (CL) and P values. RESULTS: Adjusted HRs of donor-recipient patient survival were: white to white (1); and white to black (1.22; P = .001). Graft survival HRs were black to black (1.40; P <.001); black to white (1.35; P <.001); black to Hispanic (0.87; P = .18); and black to Asian (0.69; P =.05). SUMMARY: Black donor kidneys are associated with significantly lower graft survival when transplanted into whites or blacks and are only associated with lower patient survival when these kidneys are transplanted into white recipients. The graft and patient survival rates for Asian and Latino/Hispanic recipients, however, were not affected by donor ethnicity. This analysis underscores the need for research to better understand the reasons for these disparities and how to improve the posttransplant graft survival rates of black kidney recipients.
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Etnicidad , Supervivencia de Injerto/fisiología , Trasplante de Riñón/fisiología , Donantes de Tejidos/estadística & datos numéricos , Pueblo Asiatico/estadística & datos numéricos , Población Negra/estadística & datos numéricos , Cadáver , Etnicidad/estadística & datos numéricos , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Trasplante de Riñón/mortalidad , Donadores Vivos/estadística & datos numéricos , Análisis Multivariante , Oportunidad Relativa , Grupos Raciales/estadística & datos numéricos , Análisis de Regresión , Factores de Tiempo , Obtención de Tejidos y Órganos/estadística & datos numéricos , Población Blanca/estadística & datos numéricosRESUMEN
Objectives The introduction of PSA in clinical practice has resulted in decreasing the death rate form prostate cancer and in a downward shift of the pathological stage in radical prostatectomy specimens. This seems not to be the case for bladder cancer. In order to verify this assumption, we have reviewed the charts of the patients operated on of radical prostatectomy and radical cystectomy between 1994 and 2006. METHODS 456 and 491 consecutive patients, respectively, underwent radical cystectomy and radical prostatectomy with bilateral lymph nodes dissection. We excluded all the patients who had received neoadjuvant treatment or did not undergo node dissection. The patients were divided into two consecutive groups according to the year of treatment: group 1 included pts treated from 1994 to 2000, and group 2 pts from 2001 to 2006. The histopathological findings of the two groups of pts were compared. The difference among TNM systems has been balanced evaluating histopathological reports critically and converting them to the 2002 edition. RESULTS. For patients with prostate cancer, those in group 2 had a decrease in the incidence of extracapsular extension and lymph nodes invasion. The bladder cancer patients belonging to group 2 had a greater number of T2, but there was an increased number of pN+ in this group. CONCLUSIONS Even if there is a decline in locally advanced disease in patients with bladder cancer, our retrospective analysis did not show a comparable success in early diagnosis as it did for prostate cancer. There is undoubtedly an increase in the lymph node dissemination, whether this is due to a more extended lymph node dissection or to a premature dissemination remains questionable. Public awareness regarding bladder cancer and its risk factors is limited, but several studies have reported that a delay in diagnosis of invasive bladder cancer is an adverse prognostic factor. A higher care in the development of new diagnostic markers for bladder tumors and especially in the screening protocols together with an earlier radical therapy could hopefully improve the management of such a pathology, as it happened for prostate cancer.
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Microbiological quality represents the biggest concern to the reuse of treated wastewater. This paper reports and discusses the results of an international survey on the removal of indicators of microbiological contamination in surface-flow constructed wetlands. Constructed wetlands consistently provide a reduction of 90-99% (1-2 log-removal) in the concentration of indicators such as coliform bacteria and faecal streptococci. This removal is found in wetlands treating water from different types of pretreatment (primary sedimentation, activated sludge, trickling filter, maturation ponds). On the other hand, when the influent is of high microbiological quality, wetlands act as sources of pathogenic contamination. The final water quality, however, is still compatible with medium to no-contact recreational activities and other final water uses. High variability in the effluent quality and seasonality might limit the opportunities for reuse. The role of constructed wetlands in different treatment schemes and the remaining open questions concerning removal mechanisms and reference pathogens are discussed.
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Bacterias/aislamiento & purificación , Conservación de los Recursos Naturales , Contaminantes del Agua/aislamiento & purificación , Purificación del Agua/normas , Humedales , Biodegradación Ambiental , Movimientos del Agua , Abastecimiento de AguaRESUMEN
A robust procedure for the determination of 16 US EPA PAHs in both aqueous (e.g. wastewaters, industrial discharges, treated effluents) and solid samples (e.g. suspended solids and sludge) from a wastewater treatment plant (WWTP) is presented. Recovery experiments using different percentages of organic modifier, sorbents and eluting solvent mixtures were carried out in Milli-Q water (1000 mL) spiked with a mixture of the PAH analytes (100 ng/L of each analyte). The solid phase extraction (SPE) procedures applied to spiked waste water samples (1000 mL; 100 ng/L spiking level) permitted simultaneous recovery of all the 16PAHs with yields >70% (6-13% RSD). SPE clean up procedures applied to sewage and stabilized sludge extracts, showed percent recoveries in the range 73-92% (7-13% RSD) and 71-89% (7-12% RSD), respectively. The methods were used for the determination of PAHs in aqueous and solid samples from the WWTP of Fusina (Venice, Italy). Mean concentrations, as the sum of the 16PAHs in aqueous and suspended solid samples, were found to be approx. in the 1.12-4.62 microg/L range. Sewage and stabilized sludge samples contained mean PAH concentrations, as sum of 16 compounds, in the concentration range of 1.44-1.26 mg/kg, respectively. Extraction and clean up procedures for sludge samples were validated using EPA certified reference material IRM-104 (CRM No. 912). Instrumental analyses were performed by coupling HPLC with UV-diode array detection (UV-DAD) and fluorescence detection (FLD).
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Residuos Industriales/análisis , Compuestos Policíclicos/análisis , Contaminantes Químicos del Agua/análisis , Cromatografía Líquida de Alta Presión , Italia , Estándares de Referencia , Reproducibilidad de los Resultados , Espectrometría de Fluorescencia , Espectrofotometría UltravioletaRESUMEN
The paper concerns the results of a pilot-scale study of the simulation of the start-up phase of the thermophilic semi-dry anaerobic digestion of the organic fraction of municipal solid wastes. The aim of the study was to aid and shorten the start-up phase of the full-scale plant (500 t/d) in Verona--Ca' del Bue, where the semi-dry anaerobic digestion process is being used. The substrate used in the experimentation was the mechanically sorted organic fraction of municipal solid waste (MS-OFMSW) enriched with the putrescent fraction from the source sorted OFMSW in order to simulate the substrate which is dealt with in the Verona plant. The results of the pilot scale study agreed with literature data and previous work of the authors: it showed a specific gas production of 0.23 m3/kg TVSfeed and a gas production rate of 2.1 m3/m3 d when operating at a specific organic loading rate of 0.135 kgTVSfeed/kgTVSreacter d. No problems regarding process stability were encountered in the gradual acclimation of the biomass. The design organic loading rate of 9 kg TVSfeed/m3reactor d was reached in about 30 days, during which the total solids content in the feedwas increased. Only a partial comparison with the full scale start-up, which is now in progress, is possible: this shows an initial general concordance with the results found in previous work.
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Reactores Biológicos , Eliminación de Residuos/métodos , Bacterias Anaerobias/fisiología , Biomasa , Arquitectura y Construcción de Instituciones de Salud , Compuestos Orgánicos/metabolismo , Temperatura , AguaRESUMEN
The purpose of this work was to investigate the efficacy and safety of sildenafil in combination with doxazosin for the treatment of non-organic erectile dysfunction in patients who did not respond to sildenafil. We enrolled 28 patients with non-organic erectile dysfunction, for whom 3 months of sildenafil monotherapy had failed. They were divided in two random and homogeneous groups: 14 were treated with doxazosin (4 mg daily) and sildenafil (100 mg 1 h before sexual intercourse); the other 14 patients received sildenafil and placebo. The results were assessed by means of the IIEF questionnaire before the beginning of the study, after 30 days of therapy and after 60 days. Of the 14 patients treated with doxazosin and sildenafil, 11 (78.6%) showed a statistically significant increase of IIEF; in the placebo group, only one patient (7.1%) recorded a significant IIEF increase. The differences observed in the two groups were statistically very significant (P=0.0016). Blood pressure did not show significant alterations. Side effects were minimal and even present during sildenafil monotherapy. The combination therapy with sildenafil and doxazosin resulted in the safe and effective treatment of men with non-organic erectile dysfunction for whom sildenafil alone had failed.
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Doxazosina/administración & dosificación , Disfunción Eréctil/tratamiento farmacológico , Piperazinas/administración & dosificación , Vasodilatadores/administración & dosificación , Adulto , Doxazosina/efectos adversos , Doxazosina/uso terapéutico , Quimioterapia Combinada , Humanos , Masculino , Persona de Mediana Edad , Piperazinas/efectos adversos , Piperazinas/uso terapéutico , Purinas , Retratamiento , Citrato de Sildenafil , Sulfonas , Encuestas y Cuestionarios , Resultado del Tratamiento , Vasodilatadores/efectos adversos , Vasodilatadores/uso terapéuticoRESUMEN
INTRODUCTION: Left radical nephrectomy is the second most common cause of incidental splenectomy during transabdominal oncological surgery in the upper left quadrant of the abdomen. The potential sequelae of splenic ablation are often underestimated and generally no systematic planned efforts have been undertaken to avoid a splenic injury. MATERIAL AND METHODS: We evaluated the incidence of iatrogenic splenectomy in 333 cases of left radical nephrectomy for renal cancer performed at our institute between 1970 and 1999. Two slightly different surgical techniques were adopted and after 1995 particular attention was paid to the possible causes of intraoperative splenic injury and how to avoid it. In the first group of patients (1970-1994) an anterolateral xipho-umbilical-subcostal approach was used, and in the second group (1995-1999) a cruciate "Mercedes-like" incision was always adopted. RESULTS: The incidence of iatrogenic splenectomy in the first group of patients was 13.2%, and only 2.6% in the second group. The mortality rate in the first group of patients was 6%; no mortality has been recorded in the second group. Postoperative infections averaged 12.1% in the first group and 11.6% in the second, without any difference between the two groups. However, if we consider the incidence of postoperative infections in splenectomy cases, the incidence reaches 24.2% in the first group versus no cases in the second. CONCLUSIONS: Incidental splenectomy is a potentially severe complication of transabdominal left radical nephrectomy and is often considered a price that has to be paid, particularly in cases of large tumoral masses. A more detailed knowledge of splenic anatomy, a critical consideration of the intraoperative factors that may lead to splenectomy, and the adoption of a surgical tactic borrowed from the techniques of liver transplant significantly lower the incidence of iatrogenic splenectomy.
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Complicaciones Intraoperatorias/prevención & control , Nefrectomía , Bazo/lesiones , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Persona de Mediana EdadRESUMEN
Arterial priapism is a rare condition caused by the traumatic formation of an arteriolacunar fistula. We report 2 cases of arterial priapism after cycling injuries. Both patients sustained a violent perineal trauma against the top tube on the bicycle. In both cases, penile detumescence was obtained by superselective arteriographic embolization of the fistula with gelatin sponge or microcoil. The fistula was monolateral in the first case and bilateral in the second. Cycling should be considered a possible risk factor for arterial priapism as it is for urethritis, prostatitis, hematuria, testicular torsion, scrotal and penile numbness, and erectile dysfunction.
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Ciclismo/lesiones , Perineo/lesiones , Priapismo/etiología , Adulto , Angiografía , Fístula Arteriovenosa/diagnóstico por imagen , Fístula Arteriovenosa/etiología , Fístula Arteriovenosa/terapia , Embolización Terapéutica , Humanos , Masculino , Pene/irrigación sanguínea , Priapismo/terapia , Factores de RiesgoRESUMEN
A pilot scale mesophilic anaerobic acidogenic fermenter was fed with mixtures of vegetables and fruits shredded by a hammer mill and mixed in a stock tank, in order to produce a liquid phase suitable as RBCOD source in denitrification and EBPR processes. Different operative conditions were studied working with a HRT in the range 1-12 days. The effluent coming from the fermenter was screw pressed, and the solid phase was recycled adopting different ratios to the fermenter, in order to define its effect on the final liquid phase composition. The variations of the VFA, lactate, methyl and ethyl alcohol concentrations, TCOD, SCOD and pH during more than one year were analysed and discussed both with reference to the fresh feed, and to the content of the fermenter. It was found that almost all the organic matter in the liquid phase inside the fermenter was represented by VFA (mainly acetate), lactate (in particular) and methyl and ethyl alcohols when HRT was longer than 6 days.
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Fermentación , Frutas , Verduras , ÁcidosRESUMEN
We are mainly interested in the development of CAD systems for interior design. An effective use of such systems relies to a large extent on the characteristics of their user interface. This paper describes NALIG, a system able to "understand" and "reason about" high level descriptions of spatial scenes. The user interacts with the system by using a natural language interface which, though very simple, is expressive enough to allow the description of complex configurations of objects. NALIG replies by drawing on the screen an image mirroring its own "understanding" of the scene described. The comprehension process has required the integration of different AI-techniques (e.g., natural language understanding, spatial reasoning, default and common sense reasoning).
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The anaerobic digestion of source separated organic fraction of municipal solid wastes was studied by using a stirred 3 cubic meter working volume reactor fed on a semicontinuous basis. The behaviour and performance of the digester at various organic loading rates was illustrated with particular regard to turnover of the gas production rate during a cycle in the digester feed.