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1.
Can Prosthet Orthot J ; 4(1): 36252, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-37614930

RESUMO

BACKGROUND: The subischial socket interface design is a promising new shape of socket for persons with transfemoral amputation. Typically, the proximal trim line is located distal to the ischial tuberosity, improving comfort in prosthetic users without interfering with gait parameters compared to Ischial Containment Socket (ICS). No studies have investigated the performances of a subischial sockets with suction suspension system. A new subischial socket (Hybrid Subischial Socket - HySS) combined with a hypobaric passive suspension system has been recently developed. OBJECTIVE: To assess the effects of HySS in terms of comfort, hip range-of-motion and gait parameters. METHODOLOGY: Three persons with transfemoral amputation were tested first using their usual ICS and then after one month of continuous use of HySS. FINDINGS: The following parameters improved in all participants using HySS: 1) hip range-of-motion, 2) walking speed and distance, 3) Timed-Up-and-Go-Test time, 4) stride length, 5) double support duration, 6) peak value of hip extension during stance, 7) satisfaction with the prosthesis. CONCLUSION: These findings suggest that the use of HySS could allow improvements for prosthetic use.

2.
Faraday Discuss ; 208(0): 227-242, 2018 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-29808205

RESUMO

We looked for the active hydrogen species in a highly dispersed and very homogeneous 5 wt% Pt/C industrial catalyst (Pt particle mean diameter of 2.0 ± 0.5 nm) for hydrogenation reactions, by coupling H2 adsorption measurements with Inelastic Neutron Scattering (INS). Taking advantage of the enormous progress undergone by INS instruments, we succeeded in collecting INS spectra of unprecedented quality that allowed us to: (1) demonstrate that the Pt nanoparticles are mainly located at the regular edges of the sp2 graphitic domains on the activated carbon; (2) validate that most of the H2 physisorbed on the carbon is side-on adsorbed; (3) detect for the first time H2 molecules adsorbed on hydride-covered Pt nanoparticles; (4) observe Pt-hydrides (on the Pt/C catalyst with the lowest Pt loading among those investigated by INS so far) and (5) provide evidence for the occurrence of spillover of atomic hydrogen from the Pt surface to unsaturated reactive sites located at the irregular borders of the sp2 domains on the activated carbon.

3.
Artigo em Inglês | MEDLINE | ID: mdl-26066195

RESUMO

We model long-range correlations of nucleotides in the human DNA sequence using the long-range one-dimensional (1D) Ising model. We show that, for distances between 10(3) and 10(6) bp, the correlations show a universal behavior and may be described by the non-mean-field limit of the long-range 1D Ising model. This allows us to make some testable hypothesis on the nature of the interaction between distant portions of the DNA chain which led to the DNA structure that we observe today in higher eukaryotes.


Assuntos
DNA/química , DNA/genética , Modelos Biológicos , Composição de Bases , Sequência de Bases , Cromatina/metabolismo , DNA/metabolismo , Humanos
4.
Theriogenology ; 81(4): 520-5, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24360404

RESUMO

Flow cytometry sex-sorting technology was developed in 1989. However, it is only the bovine species in which offspring of the desired sex are obtained at a commercial level. The aim of the present work was to evaluate efficiency parameters when using fresh sexed semen in a large-scale equine commercial embryo transfer program. During the 2009, 2010 and 2011 breeding seasons, 938 synchronized cycles were artificially inseminated. One hundred (10.6%) mares failed to ovulate, and for the remaining 838 useable cycles, 887 doses of sexed semen were used, representing 1.06 doses per cycle. In general, 435 (51.9%) out of 838 flushing performed resulted in the recovery of at least one embryo and 496 (59.1%) embryos were recovered, including twins and triplets. Pregnancy rate at 25 days achieved 81.5% (one embryo transferred per recipient). Embryo recovery rate was not statistically different either between preovulatory and postovulatory artificially inseminated mares or when increased quantities of sexed sperm per dose were used (15-45 million) (P > 0.05). A broad variation in embryo recovery rate was observed between the different stallions used in this study. Sex accuracy of the sex sorting assessed by ultrasound fetal sex determination was 90.3%. Finally, overall efficiency (female embryo pregnancies per useable cycles) was 39% (325/838), meaning that to obtain a female pregnancy of at least 75 days it was necessary to perform 2.5 flushing.


Assuntos
Transferência Embrionária/veterinária , Cavalos/fisiologia , Inseminação Artificial/veterinária , Sêmen/fisiologia , Pré-Seleção do Sexo/veterinária , Animais , Distribuição de Qui-Quadrado , Transferência Embrionária/métodos , Feminino , Citometria de Fluxo/veterinária , Inseminação Artificial/métodos , Masculino , Gravidez , Pré-Seleção do Sexo/métodos
5.
Phys Rev Lett ; 111(13): 132001, 2013 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-24116768

RESUMO

We propose a new method to compute glueball masses in finite temperature lattice gauge theory which at low temperature is fully compatible with the known zero temperature results and as the temperature increases leads to a glueball spectrum which vanishes at the deconfinement transition. We show that this definition is consistent with the Isgur-Paton model and with the expected contribution of the glueball spectrum to various thermodynamic quantities at finite temperature. We test our proposal with a set of high precision numerical simulations in the 3D gauge Ising model and find a good agreement with our predictions.

6.
Aging Clin Exp Res ; 25(2): 211-4, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23739907

RESUMO

Merkel cell carcinoma (MCC) is a rare neuroendocrine tumour of the skin, characterised by an aggressive clinical course. The incidence of this rare neoplasia is rapidly increasing. Herein we report our experience with a patient who developed a MCC of the inguinal region.


Assuntos
Carcinoma de Célula de Merkel/diagnóstico , Neoplasias Cutâneas/diagnóstico , Idoso de 80 Anos ou mais , Carcinoma de Célula de Merkel/radioterapia , Feminino , Humanos , Neoplasias Cutâneas/radioterapia
7.
Eur J Phys Rehabil Med ; 48(4): 613-23, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22641248

RESUMO

BACKGROUND: The factors that determine successful rehabilitation after lower limb amputation have been widely investigated in the literature, but little attention has been paid to the type of prosthesis and clinical state of the residual limb, particularly the presence of open ulcers. AIM: The aim of this study was to investigate the effects of a vacuum-assisted socket system (VASS) in a sample of trans-tibial amputees with wounds or ulcers on the stump and to evaluate prosthesis use as a primary outcome. Secondary outcome measures were mobility with the prosthesis, pain associated with prosthesis use, and wound/ulcer healing. STUDY DESIGN: Randomized controlled study. SETTING: Inpatient. POPULATION: Twenty dysvascular transtibial amputees suffering from ulcers due to prosthesis use or delayed wound healing post-amputation were enrolled. METHODS: Participants were separated into two groups: the experimental group was trained to use a VASS prosthesis in the presence of open ulcers/wounds on the stump; and the control group was trained to use a standard suction socket system prosthesis following ulcers/wounds healing. RESULTS: At the end of the 12-week rehabilitation program, all VASS users were able to walk independently with their prosthesis as reflected by a median Locomotor Capability Index (LCI) value of 42, whereas only five participants in the control group were able to walk independently with a median LCI value of 21. At the two-month follow-up, the participants used their VASS prostheses for 62 hours a week (median; range: 0-91), which was significantly longer than the control group using the standard prosthesis for 5 hours per week (range: 0-56, p=0.003). At the six-month follow-up, the difference between VASS-users (80, range: 0-112 hours a weeks) and control-users (59, range: 0-91) was no longer significant (p=0.191). Despite more intense use of the prosthesis, pain and wound healing did not significantly differ between the two groups. CONCLUSION: These results showed that the VASS prosthesis allowed early fitting with prompt ambulation recovery without inhibiting wound healing or increasing pain.


Assuntos
Cotos de Amputação/patologia , Amputados/reabilitação , Membros Artificiais/normas , Deambulação Precoce/métodos , Cicatrização/fisiologia , Cotos de Amputação/fisiopatologia , Membros Artificiais/efeitos adversos , Deambulação Precoce/efeitos adversos , Feminino , Humanos , Perna (Membro)/patologia , Perna (Membro)/cirurgia , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Desenho de Prótese , Ajuste de Prótese , Úlcera Cutânea/etiologia , Úlcera Cutânea/fisiopatologia , Úlcera Cutânea/terapia , Sucção/instrumentação , Sucção/métodos , Tíbia/patologia , Tíbia/cirurgia , Vácuo
8.
Phys Med ; 27(4): 209-23, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21071252

RESUMO

The public domain code GENIA, based on multi-printing method for producing surface sources with appropriate radioactivity, is described. The conventional technique, running on standard inkjet printer with radio-marked ink filling, is improved by repeating elementary printing commands in the same band. Well outlined sources with adjustable radioactivity can be obtained without refilling. The intrinsic limitation of printable radioactivity, depending on the value available at nozzles at printing time, was overcome. In addition the method permits the accurate calibration of the amount of activity released onto the paper.


Assuntos
Tinta , Imagens de Fantasmas , Impressão/instrumentação , Software , Raios gama , Método de Monte Carlo , Setor Público , Radioatividade , Reprodutibilidade dos Testes , Análise Espectral , Temperatura
9.
Med Phys ; 36(4): 1298-317, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19472638

RESUMO

The authors report on the performance of two small field of view, compact gamma cameras working in single photon counting in planar imaging tests at 122 and 140 keV. The first camera is based on a LaBr3: Ce scintillator continuous crystal (49 x 49 x 5 mm3) assembled with a flat panel multianode photomultiplier tube with parallel readout. The second one belongs to the class of semiconductor hybrid pixel detectors, specifically, a CdTe pixel detector (14 x 14 x 1 mm3) with 256 x 256 square pixels and a pitch of 55 microm, read out by a CMOS single photon counting integrated circuit of the Medipix2 series. The scintillation camera was operated with selectable energy window while the CdTe camera was operated with a single low-energy detection threshold of about 20 keV, i.e., without energy discrimination. The detectors were coupled to pinhole or parallel-hole high-resolution collimators. The evaluation of their overall performance in basic imaging tasks is presented through measurements of their detection efficiency, intrinsic spatial resolution, noise, image SNR, and contrast recovery. The scintillation and CdTe cameras showed, respectively, detection efficiencies at 122 keV of 83% and 45%, intrinsic spatial resolutions of 0.9 mm and 75 microm, and total background noises of 40.5 and 1.6 cps. Imaging tests with high-resolution parallel-hole and pinhole collimators are also reported.


Assuntos
Câmaras gama , Algoritmos , Compostos de Cádmio/química , Cristalização , Desenho de Equipamento , Humanos , Processamento de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Modelos Estatísticos , Fótons , Reprodutibilidade dos Testes , Semicondutores , Sensibilidade e Especificidade , Telúrio/química , Tomografia Computadorizada de Emissão de Fóton Único/métodos
10.
Langmuir ; 25(11): 6476-85, 2009 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-19348495

RESUMO

Adsorption of N2 at 77 K and scanning electron microscopy have been used to measure the changes in the support morphology, at nano- and microscale level, along the processes involved in the preparation of a supported Pd catalyst: Pd deposition, doping, and thermal treatments. Among the investigated supports, viz., activated carbons, gamma-Al2O3, SiO2, and SiO2-Al2O3 (SA), the SA one was found particularly sensitive to these processes, as a result of its high plasticity and reactivity. Involved processes can be summarized as follows: (i) During the Pd deposition, the support itself is partially dissolved and removed as a result of both the basicity of the precipitating agent and the final washing. (ii) When the undoped sample is thermally treated up to 823 K, only modest phenomena are observed. (iii) Upon doping with potassium carbonate, the support dissolution continues, and the greater the carbonate concentration, the greater the dissolution extent. In this case the dissolved material is not removed, but reprecipitates (partially outside the pores), during the subsequent drying at 393 K. (iv) When doped samples are thermally treated, the reaction between carbonate and support causes the mobilization of the support itself, with sintering phenomena that can reach the total collapse of the porous structure. The starting temperature of the pore collapse decreases with increasing potassium carbonate concentration. The modification of the support influences, directly or indirectly, the surface properties and the availability of Pd particles that can be doped or even covered by materials from support and made more or less accessible or even inaccessible by pore narrowing, widening, or blocking.

12.
Br J Radiol ; 82(976): 328-31, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19064600

RESUMO

Dose verification of intensity-modulated arc therapy using an ERGO++ treatment planning system and Elekta internal multileaf collimators is described. Prostate intensity-modulated arc therapy was planned using the arc modulation optimization algorithm inverse planning module of ERGO++. After transferring the plan to Elekta Synergy's controller (Elekta Ltd, Crawley, UK), the isocentre dose was measured and compared with a calculated dose using a pinpoint chamber and a water phantom in a cylindrical acrylic enclosure. Subsequently, an EDR2 film was placed inside a multilayer plastic phantom, and total dose distributions were measured in three axial planes as well as in the coronal and sagittal planes to compare the actual dose with the calculated dose. The dose discrepancy at the isocentre was 1.7%. The calculated gamma indices were less than 1 over 90% of the three axial planes, as well as in the coronal and sagittal planes, having a dose greater than 50% of the maximum target dose.


Assuntos
Interpretação de Imagem Assistida por Computador/instrumentação , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/instrumentação , Radioterapia de Intensidade Modulada/métodos , Algoritmos , Humanos , Masculino , Doses de Radiação , Dosagem Radioterapêutica , Rotação
13.
Sci Total Environ ; 390(2-3): 569-78, 2008 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-18035400

RESUMO

Mercury (total and organic), cadmium, lead, copper, iron, manganese, selenium and zinc concentrations were measured in different organs of 6 different cetacean species stranded in an area of extraordinary ecological interest (Cetaceans' Sanctuary of the Mediterranean Sea) along the coast of the Ligurian Sea (North-West Mediterranean). Stable-isotopes ratios of carbon ((13)C/(12)C) and nitrogen ((15)N/(14)N) were also measured in the muscle. A significant relationship exists between (15)N/(14)N, mercury concentration and the trophic level. The distribution of essential and non-essential trace elements was studied on several organs, and a significant relationship between selenium and mercury, with a molar ratio close to 1, was found in the cetaceans' kidney, liver and spleen, regardless of their species. High selenium concentrations are generally associated with a low organic to total mercury ratio. While narrow ranges of concentrations were observed for essential elements in most organs, mercury and selenium concentrations are characterised by a wide range of variation. Bio-accumulation and bio-amplification processes in cetaceans can be better understood by comparing trace element concentrations with the stable-isotopes data.


Assuntos
Cetáceos/metabolismo , Metais Pesados/farmacocinética , Poluentes Químicos da Água/farmacocinética , Animais , Carbono/análise , Carbono/farmacocinética , Feminino , Masculino , Mar Mediterrâneo , Metais Pesados/análise , Nitrogênio/análise , Nitrogênio/farmacocinética , Distribuição Tecidual , Poluentes Químicos da Água/análise
14.
Chemosphere ; 67(5): 1018-24, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17156818

RESUMO

Iodomethane is produced in the marine environment by algae and plankton. Model experiments have shown that iodomethane can dissolve a series of metal sulphides, in agreement with some of the results mentioned in the relative literature. While no dissolution of SnS was observed, PbS and HgS were dissolved proportionally with the iodomethane concentration. The two forms of HgS (cinnabar and metacinnabar) behaved differently, with metacinnabar being more soluble than cinnabar. Moreover, iodomethane can methylate lead and tin and mercury can be methylated when methyllead and methyltin compounds are present in the model system. The methylated species were identified using gas chromatography, and there is evidence that lead and tin undergo the same methylation mechanism. Preliminary experiments with natural sediments were performed, but no dissolution of Pb, Sn or Hg was observed. CAPSULE: Iodomethane can solubilize Pb and Hg sulphides, and methylate Pb and Sn, and (indirectly) Hg.


Assuntos
Hidrocarbonetos Iodados/química , Chumbo/química , Compostos de Mercúrio/química , Sulfetos/química , Compostos de Estanho/química , Poluentes Químicos da Água/química , Metilação , Solubilidade
15.
Phys Med Biol ; 51(23): 5987-6003, 2006 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-17110765

RESUMO

A multileaf collimator for electrons (eMLC) has been designed that fulfils the technical requirements for providing advanced irradiation techniques with electrons. In the present work, the basic design parameters of leaf material, leaf height, leaf width and number of leaves as well as leaf overtravel and leaf shape were determined such that an eMLC with motorized leaves can be manufactured by a company specialized in MLC technology. For this purpose, a manually driven eMLC with variable source-to-collimator distance (SCD) was used to evaluate the chosen leaf specification and investigate the impact of the SCD on the off-axis dose distribution. In order to select the final SCD of the eMLC, a compromise had to be found between maximum field size, minimum beam penumbra and necessary distance between eMLC and isocentre to eliminate patient realignments during gantry rotation. As a result, the eMLC is placed according to the target position at 72 and 84 cm SCD, respectively. This feature will be achieved by interchangeable distance holders. At these SCDs, the corresponding maximum field sizes at 100 cm source-to-isocentre distance are 20 x 20 cm and 17 x 17 cm, respectively. Finally, the off-axis dose distribution at the maximum opening of the eMLC was improved by fine-tuning the settings of the accelerator jaws and introducing trimmer bars above the eMLC. Following this optimization, a prototype eMLC consisting of 2 x 24 computer-controlled brass leaves is manufactured by 3D Line Medical Systems.


Assuntos
Elétrons/uso terapêutico , Radioterapia Conformacional/instrumentação , Fenômenos Biofísicos , Biofísica , Desenho de Equipamento , Humanos , Neoplasias/radioterapia , Radioterapia Conformacional/estatística & dados numéricos , Radioterapia de Alta Energia/instrumentação , Radioterapia de Alta Energia/estatística & dados numéricos
16.
Phys Chem Chem Phys ; 8(31): 3676-81, 2006 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-16883397

RESUMO

By diluting optically opaque carbon-supported Pd particles in silica Aerosil we succeeded in observing the IR bands of adsorbed carbonyls and extracting information on the particle dispersion. Comparison with literature single crystal data and with silica-alumina supported Pd allowed us to make an assignment in terms of linear and 2-fold bridged carbonyls formed on Pd(111) and Pd(100) faces. Two Pd/C samples have been investigated. The relative intensities of the two carbonyl families observed on the two samples are consistent with the Pd dispersion independently measured with CO chemisorption, TEM and EXAFS analysis.


Assuntos
Aldeídos/química , Óxido de Alumínio/química , Carbono/química , Paládio/química , Dióxido de Silício/química , Cinética , Microscopia Eletrônica de Transmissão , Nanoestruturas/química , Espectrometria por Raios X , Espectrofotometria Infravermelho/métodos
17.
Radiother Oncol ; 80(2): 268-73, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16890315

RESUMO

BACKGROUND AND PURPOSE: The potential benefits and limitations of different radiation techniques (stereotactic arc therapy (SRS/T), intensity modulated radiotherapy (IMRT), helical tomotherapy (HT), Cyberknife and intensity-modulated multiple arc therapy (AMOA)) have been assessed using comparative treatment planning methods on twelve patients presenting with 'benign' brain tumours. MATERIALS AND METHODS: Plans for five acoustic neurinomas, five meningiomas and two pituitary adenomas were computed to generate dose distributions for all modalities using a common CT dataset to delineate planning target volume and organs at risk. RESULTS: HT, AMOA and IMRT resulted superior to SRS/T and Cyberknife for target coverage. For the first group V(95%) ranged from 98% to 100%, minimum dose ranged from 91% to 96% and standard deviation from 0.84% to 1.67%. For organs at risk all techniques respected planning objectives with a tendency of Cyberknife and SRS/T to better spare the brain stem and the healthy brain tissue (e.g., V(20Gy) of 2.0% and 2.3%, respectively, compared to 3.1-5.0% for the other techniques). AMOA is in general preferable to IMRT for all OARs. Conformity index (CI(95)) was better for HT and Cyberknife (both 1.8) and less for AMOA and IMRT (3.9 and 3.0, respectively). CONCLUSION: All techniques provided good OAR sparing and primarily differed in target coverage indices. For the class of tumours investigated in this report, HT, AMOA and IMRT had better target coverage with HT providing the best combination of indeces. Between AMOA and IMRT, target coverage was comparable and, considering organs at risk, AMOA was slightly preferable.


Assuntos
Neoplasias Encefálicas/radioterapia , Fótons/uso terapêutico , Humanos , Meningioma/radioterapia , Neurilemoma/radioterapia , Radioterapia de Intensidade Modulada/métodos , Técnicas Estereotáxicas , Tomografia Computadorizada Espiral/métodos
18.
Percept Mot Skills ; 93(1): 139-40, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11693677

RESUMO

In 2000-2001 academic year the frequency distribution of hours slept per night was not significantly different from distributions of 1978-79 and 1988-89.


Assuntos
Sono , Estudantes/psicologia , Humanos , Inquéritos e Questionários , Fatores de Tempo
20.
Ann Chim ; 91(1-2): 23-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11329766

RESUMO

The concentration of vanadium was measured in 35 samples of the epiphytic lichen Parmelia caperata collected along the coast of the Ligurian Sea (Italy), in order to detect the possible bioaccumulation of vanadium due to a huge crude oil burning occurred in that area in 1991. The cartographic elaboration of data shows a pattern of distribution of vanadium concentrations according to different degrees of deviation from background condition, showing that 8 years later memory of the accident is still detectable in foliose lichen thalli.


Assuntos
Poluentes Atmosféricos/farmacocinética , Líquens/metabolismo , Vanádio/farmacocinética , Itália , Petróleo/efeitos adversos , Árvores
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