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1.
Data Brief ; 45: 108609, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36425958

ABSTRACT

The development of a highly efficient multijunction technology is a key challenge for the future of photovoltaic and for the transition to more renewable energy sources. In this scenario, four-terminal architecture (4T) compared to the classic tandem design allows a large intrinsic robustness to the variations of the solar spectrum, which continuously occur under normal outdoor operation conditions. On the other hand, bifacial solar cells and modules have already proven to be able to increase the energy yield of solar farms at reduced costs. For these reasons, a thorough investigation of the compatibility between these two solutions has been performed by combining a III-V semiconductor with the silicon heterojunction technology in a four-terminal device. This work has been designed in support of the research article entitled "Outdoor performance of GaAs/Bifacial Si Heterojunction four-terminal system using optical spectrum splitting" [1], which showed, through data modeling and an accurate daily analysis of the spectral distribution of solar light, how a four-terminal architecture guarantees the consistency of the bifacial gain and more robust performances than a two-terminal system. Here additional data on the manufacturing, optimization and characterization of the device are presented.

2.
Vet J ; 263: 105523, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32928492

ABSTRACT

The identification of the heart rhythm during an episode of transient loss of consciousness (TLOC) is considered the reference standard method to elucidate the underlying aetiology. This study aimed to characterise heart rhythm in dogs during TLOC using Holter and external loop recorder monitoring. We retrospectively reviewed 24-h Holter monitoring and external loop recorder tracings from 8084 dogs. Heart rhythms from dogs that experienced TLOC during the recording was analysed to identify rhythm disturbances that occurred during episodes of TLOC. Electrocardiograms (ECGs) were subsequently categorised into Type 1 (ventricular arrest), Type 2 (sinus bradycardia), Type 3 (no/slight rhythm variations), and Type 4 (tachycardia). Transient LOC was documented in 92 dogs over 230 episodes of TLOC. Percentage of cases with ECGs compatible with each classification were as follows: 72.1%, Type 1; 6.1%, Type 2; 20.9%, Type 3; and 0.9%, Type 4. Cardiac rhythm during the TLOC could have been a consequence of a neurocardiogenic mechanism in 46.7% cases, while intrinsic rhythm disturbances of the sinus node or of the atrioventricular node were diagnosed in 31.5% cases. In two cases, tachycardia was the possible cause of the TLOC. ECG patterns in dogs presenting with multiple TLOC episodes were completely reproducible during each episode. TLOC in dogs was primarily caused by ventricular arrest. Most dogs with TLOC had electrocardiographic finding suggestive of a reflex or neurally-mediated syncope, but one third had an ECG more suggestive of a conduction disorder. Distinguishing these two entities could help inform diagnostic, therapeutic, and prognostic plans.


Subject(s)
Dog Diseases/physiopathology , Electrocardiography, Ambulatory/veterinary , Heart Rate/physiology , Unconsciousness/veterinary , Animals , Arrhythmias, Cardiac/complications , Arrhythmias, Cardiac/diagnosis , Arrhythmias, Cardiac/veterinary , Dogs , Electrocardiography/veterinary , Electrocardiography, Ambulatory/methods , Female , Male , Retrospective Studies , Syncope/physiopathology , Syncope/veterinary , Unconsciousness/etiology , Unconsciousness/physiopathology
3.
Radiología (Madr., Ed. impr.) ; 60(2): 94-104, mar.-abr. 2018. ilus, tab
Article in Spanish | IBECS | ID: ibc-174070

ABSTRACT

La trombosis venosa portal (TVP) es una complicación frecuente en pacientes cirróticos. Una alternativa al tratamiento anticoagulante, dado el alto riesgo de hemorragia secundaria a hipertensión portal, es la inserción de un shunt portosistémico transyugular intrahepático (TIPS). Se han descrito tres estrategias para la inserción del TIPS: 1) recanalización portal e implantación convencional del TIPS por vía yugular; 2) recanalización portal mediante acceso percutáneo (transhepático/transesplénico), y 3) inserción del TIPS entre una vena suprahepática y una colateral periportal, sin recanalización portal. Describimos varios materiales útiles como diana fluoroscópica para la aguja del TIPS y para la recanalización portal. El objetivo de este artículo es dar a conocer el éxito en la implantación de TIPS usando las diferentes técnicas descritas combinadas, lo que representa una buena alternativa terapéutica para esos pacientes difíciles de manejar debido a su deficiente condición clínica. Por tanto, la TVP/cavernomatosis no debe considerarse como una contraindicación para TIPS


Portal vein thrombosis is a common complication in patients with cirrhosis. Anticoagulation involves a high risk of bleeding secondary to portal hypertension, so placing transjugular intrahepatic portosystemic shunts (TIPS) has become an alternative treatment for portal vein thrombosis. Three strategies for TIPS placement have been reported: 1) portal recanalization and conventional implantation of the TIPS through the jugular vein; 2) portal recanalization through percutaneous transhepatic/transsplenic) access; and (3) insertion of the TIPS between the suprahepatic vein and a periportal collateral vessel without portal recanalization. We describe different materials that can be used as fluoroscopic targets for the TIPS needle and for portal recanalization. This article aims to show the success of TIPS implantation using different combinations of the techniques listed above, which is a good treatment alternative in these patients whose clinical condition makes them difficult to manage, and to show that portal vein thrombosis/cavernous transformation should not be considered a contraindication for TIPS


Subject(s)
Humans , Male , Female , Child , Middle Aged , Venous Thrombosis/complications , Venous Thrombosis/diagnostic imaging , Hypertension, Portal/complications , Liver Cirrhosis/diagnostic imaging , Portasystemic Shunt, Transjugular Intrahepatic , Hemangioma, Cavernous/diagnostic imaging , Liver Cirrhosis/complications , Stents , Portography/methods
4.
World J Surg ; 42(8): 2285-2292, 2018 08.
Article in English | MEDLINE | ID: mdl-29387959

ABSTRACT

INTRODUCTION: Injury is the third leading cause of death in Mongolia, with a 29% increase in motor vehicle fatalities over the past decade. Half of the population lives outside the urbanized capital of Ulaanbaatar, where access to care is limited. This study evaluates and describes the Mongolian trauma system and makes recommendations for improvements. METHODS: Hospital-level data were collected, and an International Assessment of Capacity for Trauma (INTACT) score (0-10) was calculated. INTACT is a validated measure for evaluating trauma capacity in developing countries based on resource availability; a score of 10 reflects ideal staffing and equipment. The survey was administered to key staff members at 10 rural and urban hospitals in spring 2016. INTACT scores were calculated for each hospital and compared to expected INTACT scores based on the World Health Organization Guidelines for Essential Trauma Care (GETC). RESULTS: Ulaanbaatar enjoys a centralized prehospital transportation service and two appropriately resourced tertiary hospitals. Rural Mongolians rely upon regionally located tertiary facilities with similar capabilities. INTACT scores for secondary-level hospitals (n = 2) failed to meet expected GETC minimums, as did 2 of 4 primary facilities. There are no national standards guiding prehospital care, triage, or transfer. No outpatient rehabilitation facilities exist within Mongolia. CONCLUSION: The Mongolian trauma system utilizes regionalized care to provide emergency services. Among surveyed hospitals, 60% met GETC standards. Areas for improvement include increased resourcing of primary and secondary facilities, development of rural prehospital systems, adoption of universal standards for patient care, and creation of post-acute rehabilitation facilities.


Subject(s)
Emergency Medical Services , Wounds and Injuries/therapy , Health Resources , Humans , Mongolia
5.
Radiologia (Engl Ed) ; 60(2): 94-104, 2018.
Article in English, Spanish | MEDLINE | ID: mdl-29122309

ABSTRACT

Portal vein thrombosis is a common complication in patients with cirrhosis. Anticoagulation involves a high risk of bleeding secondary to portal hypertension, so placing transjugular intrahepatic portosystemic shunts (TIPS) has become an alternative treatment for portal vein thrombosis. Three strategies for TIPS placement have been reported: 1) portal recanalization and conventional implantation of the TIPS through the jugular vein; 2) portal recanalization through percutaneous transhepatic/transsplenic) access; and (3) insertion of the TIPS between the suprahepatic vein and a periportal collateral vessel without portal recanalization. We describe different materials that can be used as fluoroscopic targets for the TIPS needle and for portal recanalization. This article aims to show the success of TIPS implantation using different combinations of the techniques listed above, which is a good treatment alternative in these patients whose clinical condition makes them difficult to manage, and to show that portal vein thrombosis/cavernous transformation should not be considered a contraindication for TIPS.


Subject(s)
Hypertension, Portal/complications , Portal Vein/abnormalities , Portasystemic Shunt, Transjugular Intrahepatic/methods , Venous Thrombosis/complications , Venous Thrombosis/surgery , Adolescent , Adult , Female , Humans , Male , Middle Aged , Retrospective Studies , Treatment Outcome
6.
Radiología (Madr., Ed. impr.) ; 57(5): 419-427, sept.-oct. 2015. tab, ilus
Article in Spanish | IBECS | ID: ibc-141047

ABSTRACT

Objetivo. Determinar el grado de necrosis tumoral en la pieza quirúrgica de hepatocarcinomas tratados con microesferas precargadas con doxorrubicina (QETA-DEB) y su relación con factores morfológicos y biomarcadores de imagen. Material y Métodos. 21 pacientes a quienes se realizó quimioembolización arterial selectiva con partículas DC-Beads (Biocompatibles, UK) fueron posteriormente trasplantados y analizados los hígados histológicamente. Resultados. Se detectaron por diferentes técnicas de imagen 43 nódulos con un tamaño medio de 25 mm. Angiográficamente eran 25 nódulos hipervascularizados, 12 discretamente vascularizados y 6 avasculares. En la pieza se encontraron 81 HCCs con un tamaño medio de 15 mm.; dos presentaron infiltración vascular y otros dos infiltración capsular. La necrosis media conseguida tras QETA-DEB fue del 39% siendo >60% en 28 HCCs y <60% en 52. Encontramos correlación estadística entre el índice de necrosis conseguida con el tiempo que transcurre desde la última QETA-DEB hasta el trasplante (siendo significativamente menor la necrosis conforme aumenta el tiempo), con el número de nódulos encontrados en la pieza y con la infiltración capsular. Asimismo, podemos predecir que cuando por técnicas de imagen detectamos 1 ó 2 nódulos tendremos más probabilidad de conseguir de manera significativa índices de necrosis > 90%. Sin embargo, ni el tamaño de los nódulos detectados por técnicas de imagen, ni el patrón de realce post-contraste ni el número de QETA-DEBs realizadas influye significativamente en la necrosis conseguida. Conclusión. La necrosis producida depende del tiempo en lista de espera, del número de nódulos en la pieza y de la infiltración capsular del tumor (AU)


Objective. To determine the degree of tumor necrosis in surgical specimens of hepatocellular carcinomas treated with microspheres preloaded with doxorubicin and to analyze the relationship between the degree of necrosis and a) morphologic factors and b) imaging biomarkers. Material and methods. We studied the livers of 21 patients who had undergone selective arterial chemoembolization with DC beads (Biocompatibles, UK) before receiving liver transplants. Results. Imaging techniques detected 43 nodules (mean size, 25 mm). Angiography showed 25 hypervascularized nodules, 12 slightly vascularized nodules, and 6 avascular nodules. A total of 81 hepatocellular carcinomas (mean size, 15 mm) were detected in the specimens: two were capsular and two had vascular infiltration. The mean degree of necrosis after chemoembolization was 39%; necrosis was greater than 60% in 28 hepatocellular carcinomas and less than 60% in 52. The degree of necrosis correlated significantly with the time elapsed between the last chemoembolization treatment and liver transplantation (the degree of necrosis decreased as time increased), with the number of nodules in the specimen, and with capsular infiltration. When imaging techniques detected 1 or 2 nodules, there was a greater probability of achieving greater than 90% necrosis. No relation with the degree of necrosis achieved was found for the size of the nodules detected at imaging, the enhancement pattern, or the number of chemoembolization treatments. Conclusion. The degree of necrosis achieved depends on the time spent on the waiting list, on the number of nodules in the specimen, and on whether capsular infiltration is present (AU)


Subject(s)
Female , Humans , Male , Middle Aged , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular , Carcinoma, Hepatocellular/diagnosis , Chemoembolization, Therapeutic/instrumentation , Chemoembolization, Therapeutic/methods , Chemoembolization, Therapeutic , Doxorubicin/therapeutic use , Chemoembolization, Therapeutic/trends , Doxorubicin/pharmacology , Doxorubicin/pharmacokinetics , Microspheres , Angiography , Biomarkers, Pharmacological/metabolism , Liver Transplantation/methods , Magnetic Resonance Imaging/methods , Magnetic Resonance Spectroscopy/methods
7.
Food Res Int ; 76(Pt 3): 852-859, 2015 Oct.
Article in English | MEDLINE | ID: mdl-28455071

ABSTRACT

Globe artichoke contributes to the healthiness of the Mediterranean diet, but its nutraceutical value in response to its agronomy has not been investigated in any detail to date. Here, the effect of two contrasting fertilizer regimes (one balanced and the other excessive) on the sugar, ascorbic acid and total polyphenol content, the polyphenol profile and the antioxidant activity of the two cultivars 'Apollo' and 'Tema 2000' were monitored in plants grown in three locations in Sicily ('Landolina', 'Iannarello' and 'Zotto'), which contrasted for soil type. The balanced fertilizer regime favored the content of sucrose, inulin, ascorbic acid and polyphenols (in particular that of 1,5-di- and 5-O-caffeoylquinic acid, along with apigenin 7-O-glucuronide). It was also more supportive of a high antioxidant activity. There was a pronounced cultivar and trial location effect, especially in terms of the accumulation of antioxidant compounds. Plants grown at 'Landolina' responded more strongly than at the other two locations to the fertilizer regime with respect to both ascorbic acid and total polyphenol content. The conclusion was that providing a balanced supply of nitrogen/phosphorus/potassium (NPK) via fertilizer application can enhance the nutraceutical value of globe artichoke, although the effect is modulated by both genetic factors and soil type.

8.
Radiologia ; 57(5): 419-27, 2015.
Article in English, Spanish | MEDLINE | ID: mdl-25535030

ABSTRACT

OBJECTIVE: To determine the degree of tumor necrosis in surgical specimens of hepatocellular carcinomas treated with microspheres preloaded with doxorubicin and to analyze the relationship between the degree of necrosis and a) morphologic factors and b) imaging biomarkers. MATERIAL AND METHODS: We studied the livers of 21 patients who had undergone selective arterial chemoembolization with DC beads (Biocompatibles, UK) before receiving liver transplants. RESULTS: Imaging techniques detected 43 nodules (mean size, 25 mm). Angiography showed 25 hypervascularized nodules, 12 slightly vascularized nodules, and 6 avascular nodules. A total of 81 hepatocellular carcinomas (mean size, 15 mm) were detected in the specimens: two were capsular and two had vascular infiltration. The mean degree of necrosis after chemoembolization was 39%; necrosis was greater than 60% in 28 hepatocellular carcinomas and less than 60% in 52. The degree of necrosis correlated significantly with the time elapsed between the last chemoembolization treatment and liver transplantation (the degree of necrosis decreased as time increased), with the number of nodules in the specimen, and with capsular infiltration. When imaging techniques detected 1 or 2 nodules, there was a greater probability of achieving greater than 90% necrosis. No relation with the degree of necrosis achieved was found for the size of the nodules detected at imaging, the enhancement pattern, or the number of chemoembolization treatments. CONCLUSION: The degree of necrosis achieved depends on the time spent on the waiting list, on the number of nodules in the specimen, and on whether capsular infiltration is present.


Subject(s)
Antibiotics, Antineoplastic/administration & dosage , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/therapy , Chemoembolization, Therapeutic/methods , Doxorubicin/administration & dosage , Liver Neoplasms/pathology , Liver Neoplasms/therapy , Adult , Aged , Carcinoma, Hepatocellular/surgery , Drug Carriers , Female , Humans , Liver Neoplasms/surgery , Liver Transplantation , Male , Middle Aged , Retrospective Studies
9.
Scand J Med Sci Sports ; 21(6): e247-59, 2011 Dec.
Article in English | MEDLINE | ID: mdl-21210860

ABSTRACT

Internet websites offering androgenic anabolic steroids (AAS) were identified and available products were examined. Keywords for the website search were: "anabolic steroids," "anabolic steroids buy," "anabolic steroid purchase." The first 10 websites offering AAS in the first 10 pages of results were considered. At least two AAS-containing products per website were selected. Thirty AAS-selling websites were identified, mainly located in the United States (46.7%) and Europe (30%). Most websites sold other anabolic/ergogenic products (clenbuterol, 76.7%; GH/IGF, 60.0%; thyroid hormones, 46.7%; erythropoietin, 30.0%; insulin, 20.0%) or products for AAS-related adverse effects (mainly: estrogen antagonists, 63.3%; products for erectile dysfunction, 56.7%; 5α-reductase inhibitors, 33.3%; anti-acne products, 33.3%). AAS were sold as medicines (69.6%) or as dietary supplements (30.4%). AAS in medicines were mainly: nandronole (20.4%), methandrostenolone (18.4%), and testosterone (12.2%). Dietary supplements contained mainly DHEA and included several fake compounds. Manufacturers were declared for 97.9% of medicines and 66.7% of dietary supplements; however, several manufacturers were not found on the Internet. Described benefits were usually few adverse effects and no estrogenicity. Toxicity was seldom reported and presented as mild. Recommended doses were two-fourfold higher than current medical recommendations. In conclusion, misleading information and deceiving practices were common findings on AAS-selling websites, indicating their deleterious potential for public health.


Subject(s)
Anabolic Agents , Androgens , Commerce , Internet , Anabolic Agents/administration & dosage , Anabolic Agents/economics , Anabolic Agents/supply & distribution , Androgens/administration & dosage , Androgens/economics , Androgens/supply & distribution , Directories as Topic , Female , Humans , Internationality , Male , Search Engine
10.
Nanotechnology ; 20(15): 155201, 2009 Apr 15.
Article in English | MEDLINE | ID: mdl-19420540

ABSTRACT

We present a compact model of transport through a random distribution of interacting quantum dots embedded in a dielectric matrix. The model is based on a network of interconnected tunnel junctions sandwiched between two electrodes, resulting in a system of nonlinear differential equations which is numerically solved for a given time-dependent voltage applied to the gate. The capacitance matrix, electron/hole tunneling currents and the effective area of conduction between quantum dots are calculated at each integration step. The transport properties obtained from the model are successfully validated against experimental data for a silicon nanocrystal basic MOS cell, showing its potential applicability to non-volatile memories. In addition, through a simple rate equation, the calculated charge flux tunneling or impacting the nanocrystals is converted into electroluminescence. In this regard, we discuss the origin of the recently reported field effect luminescence in silicon nanocrystals. It is found that the idea of quantum-confined exciton creation through sequential injection of opposite sign carriers is in contradiction with the model and with the electron/hole tunneling time ratio obtained through the WKB approximation due to the difference in the electron and hole potential barrier heights. We show how our model of transport, along with a rate equation with the reported value for the absorption cross section for electrical excitation of silicon nanocrystals (approximately 10(-14) cm(2)), is in good agreement with experimental data obtained under pulsed excitation, without requiring further assumptions such as the formation of excitons from hole tunneling into electron-charged nanocrystals, revealing impact excitation of electrons/holes from the same substrate as the physical origin of the observed field effect luminescence.

11.
J Nanosci Nanotechnol ; 7(1): 322-8, 2007 Jan.
Article in English | MEDLINE | ID: mdl-17455498

ABSTRACT

In this paper we present experimental evidence for single-electron phenomena in solid-state memories based on silicon nanocrystals as storage elements. The stepwise evolution of the channel current of a written memory cell biased in the subthreshold regime is monitored by means of a purposely designed low noise acquisition system with a bandwidth of 1 kHz. Each channel current step-up is ascribed to a single-electron emission from the silicon nanocrystal to the silicon substrate and each current step-down is ascribed to a single-electron capture from the silicon substrate into the silicon nanocrystal. The effect of the measurement system bandwidth on the detection of single-electron events is discussed and a procedure for extracting the threshold voltage shift associated to these events is proposed. It is shown that single-electron charging and discharging events in a memory cell with an area of 4.5 x 10(-10) cm2 can cause threshold voltage shift at room-temperature of the order of several millivolts. Qualitative explanation for the observed threshold voltage shift distribution is given.


Subject(s)
Computer Storage Devices , Nanoparticles/chemistry , Nanotechnology/methods , Silicon/chemistry , Electrochemistry/methods , Electrons , Information Storage and Retrieval , Ions , Microscopy, Electron, Transmission , Nanotechnology/instrumentation , Software , Surface Properties , Temperature , Time Factors
12.
Minerva Stomatol ; 54(10): 531-40, 2005 Oct.
Article in English, Italian | MEDLINE | ID: mdl-16224373

ABSTRACT

AIM: The aim of this work is to compare the adhesion of the glass-ceramic (empress II) to the composite cement and the adhesion of the ceromer to the composite cement. METHODS: From each of the above materials, 10 little blocks, of 8 x 6 x 2 mm size, have been prepared. All the surface treatments suggested by the manufacturing industry have been performed: sandblasting and acid-etching of the ceramic, ceromer surface roughening with diamond bur and silanization and bonding application on both materials. A homogeneous layer of cement has been placed between couples of blocks of the same material and photopolymerised. Every sample, consisting of 2 bonded blocks, has been submitted to a traction force on a universal test machine connected with a computerized measure system (SINTEC D/10). Samples have been anchored to the machine binding devices by a bicomponent epoxy glue. Data on the breaking charge have been recorded and an analysis of the broken surfaces has been performed in order to classify the breaking modalities. RESULTS: The results ontained showed that the composite-glass-ceramic adhesion force (mean value 64 Mpa) was remarkably higher than the composite-ceromer adhesion (mean value 37.21 Mpa). CONCLUSIONS: The analysis of the broken surfaces by SEM showed that a mixed fracture occurred in all samples (both partly adhesive and cohesive).


Subject(s)
Ceramics , Composite Resins , Dental Cements , Dental Materials , Materials Testing
13.
Neurol Sci ; 26(2): 89-94, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15995825

ABSTRACT

The objective was to investigate, in the rat, the effects of maternal exposure to vigabatrin (VGB) on the postnatal motor-cognitive behaviour of the offspring. We used an experimental evaluator-blind, placebo-controlled study in the rat. Ten pregnant rats were divided into five groups and treated with different doses of VGB (250, 500, 750, 1000 mg/kg/day) or placebo from gestation day (GD) 6 to GD10. After delivery, 56 pups (40 pups prenatally exposed to VGB and 16 pups exposed to placebo) were evaluated for motor-cognitive behaviour throughout postpartum day 40. At the end of testing sessions the animals were sacrificed and brain tissues processed for biochemical analysis of GABA levels. Body weight of pups and young rats whose mothers were treated with a dose of 750 mg/kg/day were significantly lower both at birth and during the whole postnatal life with respect to the control groups. Young rats of this group exhibited impaired performance in both the open-field and water maze tasks. Brain GABA contents were dramatically increased in this group of rats. No other significant nutritional, biochemical or behavioural changes were observed after treatments with doses of VGB lower than 750 mg/kg/day. The exposure to a dose of 1000 mg/kg caused abortion. Maternal exposure to VGB at relatively high doses (750 mg/kg/day) is likely to cause some important changes of the nutritional status during the pre- and postnatal life. Thus, the biochemical and cognitive abnormalities observed in this study could be related to some disturbances of brain development induced by malnutrition and/or to a disturbance of neuronal programming of the gabaergic system.


Subject(s)
Anticonvulsants/toxicity , Maternal Exposure , Prenatal Exposure Delayed Effects , Vigabatrin/toxicity , Animals , Animals, Newborn , Behavior, Animal/drug effects , Birth Weight/drug effects , Body Weight/drug effects , Brain Chemistry/drug effects , Dose-Response Relationship, Drug , Exploratory Behavior/drug effects , Female , Litter Size/drug effects , Male , Maze Learning/drug effects , Motor Activity/drug effects , Placebos , Pregnancy , Rats , Time Factors , gamma-Aminobutyric Acid/metabolism
14.
Orbit ; 23(3): 161-8, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15545129

ABSTRACT

AIM: The purpose of this study was to test the reliability of an exophthalmometer commonly used in the Netherlands; to determine the exophthalmometry value distribution with this instrument and to assess the upper exophthalmometry limits of normal in a healthy, adult, Caucasian, Dutch population. Furthermore, to assess the effects of gender and age on exophthalmometry readings in this group and in a group of Graves' patients by comparing healthy, adult, Caucasian, Dutch individuals with adult, Caucasian, Dutch Graves' patients. METHODS: To test the reliability of our Hertel exophthalmometer, we determined the interobserver variation between two observers by measuring 160 eyes in healthy, adult, Caucasian, Dutch females and males (10 females and 10 males in each decade between 20 and 60 years of age). These data were also used for the assessment of the Hertel value distribution and for defining the upper limits of normal in these individuals by logistic regression analysis. The effects of disease, age and gender were established using these data plus data of a retrospective study of 393 adult, Caucasian, Dutch females (n=294) and males (n=99) with Graves' orbitopathy in whom Hertel values were measured with the same exophthalmometer. RESULTS: Exophthalmometry using an Hertel exophthalmometer appeared reliable (Pearson correlation coefficient for interobserver variation 0.89; 96% of the Hertel values measured by two observers were within the limits (of 2 mm) of agreement). Hertel values usually show a normal distribution in healthy individuals and in Graves' patients and are sex- and age-dependent, but there was no dependence on age in this small series in adults. Logistic regression analysis revealed an upper limit of normal of 16 mm in females and 20 mm in males in our group, using the exophthalmometer described. CONCLUSIONS: Exophthalmometry is reliable and absolute measurement of proptosis is feasible. International standardization of Hertel exophthalmometry is required in order to compare exophthalmometry data in the literature reliably.


Subject(s)
Diagnostic Techniques, Ophthalmological/instrumentation , Exophthalmos/diagnosis , Graves Disease/diagnosis , Adult , Female , Humans , Male , Middle Aged , Observer Variation , Reference Values , Reproducibility of Results , Retrospective Studies
15.
Phys Rev Lett ; 90(16): 167601, 2003 Apr 25.
Article in English | MEDLINE | ID: mdl-12732008

ABSTRACT

We report a sharp threshold at 4 V in the growth rate of breakdown spots in thin films of SiO2 on silicon. This provides some of the first information concerning the electronic structure of the breakdown spot.

16.
Minerva Stomatol ; 51(9): 371-6, 2002 Sep.
Article in Italian | MEDLINE | ID: mdl-12473973

ABSTRACT

BACKGROUND: Ultraviolet light exposure produces chromatic changes in composites used for esthetic restoration. The aim of the study was to compare the chromatic changes induced by accelerated aging in two composites of new generation: Tetric Ceram and Diamond Crown. METHODS: Five samples were prepared for each composite, each divided into two pieces, one exposed to accelerated aging obtained by ultraviolet-light exposure for 24 hours, and one maintained in dark. Thereafter, the samples were lighted by a light beam and the percentage of reflected light was assessed. The distribution of the levels of red, green and blue was assessed using a camera connected to a PC with a software for image processing. RESULTS: For both the composites, the values of the three colors were significantly lower in the samples artificially aged (p<0.0001). The values concerning to the Tetric Ceram were significantly lower than those of Diamond Crown (p<0.0001). The latter showed aging-induced variation significantly smaller than the former. CONCLUSIONS: Both the composites showed significant chromatic variations after 24 hours artificial aging. Diamond Crown showed significantly better stability.


Subject(s)
Biocompatible Materials/radiation effects , Composite Resins/radiation effects , Color , Colorimetry , Image Processing, Computer-Assisted , Materials Testing , Photochemistry , Spectrophotometry , Time Factors , Water
17.
Eur J Clin Invest ; 31(10): 876-9, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11737225

ABSTRACT

BACKGROUND: Nitric oxide (NO) is one of the most powerful antibacterial compounds. We investigated if NO oral production increases during dental plaque deposition. MATERIALS AND METHODS: Oral NO and salivary nitrite were measured in 31 healthy subjects - 11 smokers and 20 nonsmokers - with natural healthy teeth, in the morning after tooth cleaning (baseline), after withdrawal of oral hygiene for 24 h and again after tooth cleaning. RESULTS: NO and nitrite were significantly higher during plaque deposition than with clean teeth: mean NO values +/- SEM were 44.3 +/- 4.9 parts per billion (ppb) at baseline, 58.8 +/- 3.7 ppb with plaque and 43.6 +/- 3.7 ppb after tooth cleaning, P < 0.05; nitrite values were 32.9 +/- 5.5 microm at baseline, 66.4 +/- 8.2 with plaque and 37.5 +/- 5.5 after tooth cleaning, P < 0.01. During plaque deposition, oral NO was significantly directly related to salivary nitrite (r = 0.497, P = 0.002) and so were their respective changes after tooth cleaning (r = 0.577, P < 0.001). Smokers had significantly lower oral NO than nonsmokers, with both clean and dirty teeth (P < 0.001), and higher bacteria counts in the plaque (38.6 +/- 11.5 vs. 19.9 +/- 2.3, P = 0.046). CONCLUSIONS: Oral NO production increases during de novo deposition of dental plaque. NO might be an early host defence mechanism against bacterial proliferation in the plaque. Such a mechanism is inhibited by cigarette smoking.


Subject(s)
Dental Plaque/etiology , Dental Plaque/metabolism , Nitric Oxide/metabolism , Adult , Anti-Bacterial Agents/metabolism , Colony Count, Microbial , Dental Plaque/microbiology , Female , Humans , Male , Mouth/metabolism , Mouth/microbiology , Nitrites/metabolism , Saliva/metabolism , Smoking/adverse effects , Smoking/metabolism , Toothbrushing
18.
Stud Health Technol Inform ; 84(Pt 2): 1379-83, 2001.
Article in English | MEDLINE | ID: mdl-11604953

ABSTRACT

The paper presents DoMiner, a data mining tool for the analysis of patient flows among public hospitals and care units. DoMiner is based on the theory of rough sets, and allows for the extraction of association rules from data base tables. The paper describes both the clustering and rule extraction algorithm of DoMiner, and illustrates an introductory analysis example.


Subject(s)
Algorithms , Data Interpretation, Statistical , Information Storage and Retrieval/methods , Decision Support Techniques , Emergency Service, Hospital/organization & administration , Humans , Patient Discharge
19.
Int J Prosthodont ; 14(1): 9-14, 2001.
Article in English | MEDLINE | ID: mdl-11842913

ABSTRACT

PURPOSE: The influence of different types of posts and cores on light transmission through all-ceramic crowns was assessed by spectrophotometric analysis and clinical evaluation. MATERIALS AND METHODS: Three extracted natural teeth were replicated in acrylic resin, with roots prepared to receive standardized posts and cores. Using a silicone impression material as a template, various prosthodontic reconstructions were obtained by combining four types of posts and cores (polished and matte-finished gold alloy, all-ceramic, and ceramized metal alloy) and three types of all-ceramic crowns (IPS-Empress 2 surface-colored, IPS-Empress 2 stratified, and In-Ceram). The spectrophotometric analysis was performed in the dark at 25 degrees C. The teeth were backlit with an incandescent lamp at the color temperature of A illuminant and shielded to avoid spurious light entering the spectrophotometer. The transmitted light was analyzed in terms of luminance at four points of the sample surface (cervical, middle, incisal, and proximal). Twelve measurements were performed for the natural teeth, and 144 were performed for the artificial teeth. RESULTS: Natural teeth had the highest luminance. Among all-ceramic crowns, surface-colored IPS-Empress 2 had the highest luminance, and stratified IPS-Empress 2 had the lowest. Regarding posts and cores, the luminance was highest with the all ceramic, lower with the ceramized and the polished gold alloy (which had very similar luminance), and lowest with the matte-finished gold alloy. No significant difference among prosthodontic combinations was detected under clinical observation. CONCLUSION: The surface-colored glass ceramic (IPS-Empress 2) was the most translucent crown. At the standard crown thickness used, there were small, significant spectrophotometric, but not clinical, differences among the combinations tested. These findings show no esthetic contraindications for the use of polished gold alloy posts and cores with all-ceramic crowns.


Subject(s)
Ceramics/chemistry , Crowns , Dental Porcelain/chemistry , Dental Prosthesis Design , Post and Core Technique , Acrylic Resins , Aluminum Oxide/chemistry , Aluminum Silicates/chemistry , Color , Colorimetry , Darkness , Esthetics, Dental , Gold Alloys/chemistry , Humans , Light , Metal Ceramic Alloys/chemistry , Models, Dental , Palladium/chemistry , Photometry , Post and Core Technique/instrumentation , Potassium Compounds/chemistry , Spectrophotometry , Statistics as Topic , Surface Properties , Temperature , Tooth Crown/anatomy & histology , Tooth Preparation, Prosthodontic , Transillumination
20.
Tech Urol ; 6(4): 282-7, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11108567

ABSTRACT

PURPOSE: Previous studies have indicated that high-energy transurethral microwave thermotherapy (TUMT) requires intravenous (IV) sedation and/or narcotics for patient tolerance. This study was performed to determine tolerability, patient acceptance, and efficacy of TUMT using both low- and high-energy protocols in a single United States university setting. MATERIALS AND METHODS: Between August 11, 1997 and October 28, 1999, 210 men (mean age 64.9 +/- 9.1 years) presenting with symptomatic benign prostatic hyperplasia (BPH) received treatment with a Prostatron TUMT using either the low-energy Prostasoft 2.O or high-energy Prostasoft 2.5 software. Each patient had digital rectal examination and prostate-specific antigen level consistent with BPH, American Urological Association symptom score > or = 15, and Qmax <15 mL/s. Each patient received TUMT with only ibuprofen 400 mg by mouth (PO), lorazepam 1.0 mg PO, and ketorolac 30 mg intramuscularly (IM) prior to TUMT. A few patients who were concerned about limited pain threshold received oxycodone 5 mg/acetaminophen 325 mg PO. Of 210 patients treated, 12-month efficacy data were available for analysis in 80 patients. RESULTS: Forty-eight men (mean age 65 +/- 9.2 years) received low-energy 2.0 software TUMT, and 32 men (mean age 65.1 +/- 9.2 years) were treated with high-energy 2.5 software. Mean prostatic volume was 44.3 +/- 23.9 mL and 60.7 +/- 26.4 mL for the 2.0 and 2.5 groups, respectively. Mean energy delivered was 108.8 +/- 50.4 kJ and 173.1 +/- 41.1 kJ for the 2.0 and 2.5 treatment groups, respectively. International Prostate Symptom Score decreased from 23 pre-TUMT to 8 post-TUMT and 21 pre-TUMT to 10 post-TUMT at 12 months in the 2.0 and 2.5 groups, respectively. Mean peak flow rate improved 31.9% from 9.1 mL/s pre-TUMT to 12.0 mL/s post-TUMT and 45.8% from 9.6 mL/s pre-TUMT to 14.0 mL/s post-TUMT at 12 months in the 2.0 and 2.5 groups, respectively. All but two patients tolerated treatment without IV sedation. One patient experienced intolerable rectal spasm, and treatment was terminated in another patient because of poorly controlled hypertension. CONCLUSIONS: Patients can be treated safely with TUMT using either low or high energy, with almost universal patient tolerance and without the need for IV sedation or narcotics, if they premedicated effectively using a PO/IM regimen. Patients experience significant relief of symptoms whether low- or high-energy TUMT is used; however, high-energy TUMT improves flow rate to a greater extent than does low-energy therapy.


Subject(s)
Hyperthermia, Induced/methods , Microwaves/therapeutic use , Prostatic Hyperplasia/therapy , Aged , Analgesics/administration & dosage , Humans , Male , Middle Aged , Patient Acceptance of Health Care , Prostate-Specific Antigen/analysis , Treatment Outcome , Urethra , Urodynamics
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