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1.
Braz J Biol ; 84: e279583, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38985060

RESUMO

We aimed to characterize the adult and regenerating tree components and their relationships with soil characteristics of a native vegetation remnant in Cuiabá, Mato Grosso, Brazil. The area of the fragment is stratified into "dry area" (lithic neosoil) and "damp area" (gleisoil). We conducted a forest inventory with a random distribution of 25 parcels. We analyzed the physical and chemical components of the soil. We evaluated the vegetation's horizontal structure, diversity, and sample sufficiency using the Bootstrap richness estimator. We classified the species according to dispersal syndrome and ecological group. Overall, we found 93 species in the adult layer and 70 species in the regenerating layer. The similarity dendrograms based on the two evaluated indices demonstrated the existence of the two initially stratified environments in both strata. The IndVal (%) indicated that the set of indicator species differed between the strata. Thereby, the fragment is in an intermediate stage of successional progression. PCA showed that plots in the wet area had higher pH values and Ca, Zn, and Fe levels, while plots in the dry area did not clearly distinguish, varying in terms of K, B, and organic matter content. In CCA, a set of species that occurred exclusively in the damp area showed a strong relationship with the analyzed variables. The area is a diverse ecosystem that efficiently provides ecosystem services to society and should be the subject of long-term conservation and research.


Assuntos
Biodiversidade , Florestas , Solo , Brasil , Solo/química , Árvores/classificação
2.
Musculoskelet Surg ; 106(1): 83-87, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32949004

RESUMO

PURPOSE: Periprosthetic fractures after hip prosthesis represent a constantly increasing clinical problem and a challenging complication to treat surgically. Among these, type B proximal femur fractures should be diagnosed correctly to be treated surgically. The aim of this study was to re-evaluate the type of surgical treatment of periprosthetic fractures. METHODS: We examined the cases treated between January 2012 and February 2018, classifying them according to the U.C.S. AO/OTA. We evaluated the radiographic outcome according to the Beals and Tower criteria. Patients still alive were also re-evaluated according to the H.H.S. and the WOMAC score. RESULTS: We treated 48 patients (12 men, 35 women, average age 81 years), divided into 24 type B1, 14 type B2 and 10 type B3 fractures. The overall consolidation rate was 95.4%, while the major complication (implant dislocation, pseudoarthrosis and deep infection) rate was 12.5%. Clinically, it was possible to reassess 34 patients with a mean follow-up of 38.4 months, an average HHS of 75.89 and a mean WOMAC score of 79.93. CONCLUSIONS: Periprosthetic type B fractures are difficult to manage and require careful preoperative planning and appropriate intraoperative management. However, the overall clinical and radiographic result was satisfactory, although patients should still be aware of the risk of complications associated with this type of fracture.


Assuntos
Artroplastia de Quadril , Fraturas do Fêmur , Fraturas Periprotéticas , Idoso de 80 Anos ou mais , Artroplastia de Quadril/efeitos adversos , Feminino , Fraturas do Fêmur/diagnóstico por imagem , Fraturas do Fêmur/etiologia , Fraturas do Fêmur/cirurgia , Fêmur/cirurgia , Fixação Interna de Fraturas , Humanos , Masculino , Fraturas Periprotéticas/diagnóstico por imagem , Fraturas Periprotéticas/etiologia , Fraturas Periprotéticas/cirurgia , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
3.
Phys Rev Lett ; 127(13): 131802, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34623867

RESUMO

Searches for the lepton number violating K^{+}→π^{-}µ^{+}e^{+} decay and the lepton flavor violating K^{+}→π^{+}µ^{-}e^{+} and π^{0}→µ^{-}e^{+} decays are reported using data collected by the NA62 experiment at CERN in 2017-2018. No evidence for these decays is found and upper limits of the branching ratios are obtained at 90% confidence level: B(K^{+}→π^{-}µ^{+}e^{+})<4.2×10^{-11}, B(K^{+}→π^{+}µ^{-}e^{+})<6.6×10^{-11} and B(π^{0}→µ^{-}e^{+})<3.2×10^{-10}. These results improve by 1 order of magnitude over previous results for these decay modes.

4.
J Phys Condens Matter ; 33(29)2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-33979790

RESUMO

Extended x-ray absorption fine structure (EXAFS) has been measured at theKedge of Sn in SnTe in the temperature range from 5 to 480 K. EXAFS results are consistent with the presence of a local rhombohedral distortion in the full temperature range from 5 to 300 K, even well above the ferroelectric transition temperature, suggesting a partial order-disorder character of the transition. At and above 300 K, the anomalous behaviour of the third and fourth EXAFS cumulants reveals a modification of the anharmonicity of the effective pair potential, possibly connected with the softening of high frequency modes or to the presence of multiple phases.

5.
Aust Vet J ; 98(6): 225-231, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32189335

RESUMO

Four dogs with anticoagulant rodenticide toxicosis were treated with intravenous vitamin K1 in lieu of plasma transfusion due to client cost constraints. Two dogs experienced a suspected anaphylactoid reaction, necessitating cessation of the treatment in one dog. Prothrombin time was rechecked 1 h after treatment in the remaining three dogs and all results were within the normal reference range. All four dogs were discharged from hospital within 48 h of presentation. Intravenous vitamin K1 rapidly reverses the coagulopathic state in dogs with anticoagulant rodenticide toxicosis. It is a viable alternative therapy to plasma transfusion if circumstances preclude its use; however, patients must be monitored for anaphylactoid reactions.


Assuntos
Doenças do Cão , Rodenticidas , Animais , Anticoagulantes , Transfusão de Componentes Sanguíneos/veterinária , Cães , Plasma , Tempo de Protrombina/veterinária , Vitamina K 1
6.
Musculoskelet Surg ; 104(2): 195-200, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31147964

RESUMO

Patient-specific instrumentation is a surgical technique that was created to improve the accuracy of implantation, surgical time and workflow in total knee arthroplasty. This study is a single-center, single-surgeon randomized clinical trial. The aim of this work was to evaluate clinical efficacy of PSI versus standard surgical instrumentation in malalignment risk and blood loss reduction. From April 2015 to September 2016, 40 patients for a total of 40 knees were included in the randomization process. Each patient underwent CT scan of the lower limb including hip, knee and ankle joint with the realization of the PSI system and the TKA with Medacta GMK Primary®. Patients were evaluated 1 month after surgery with X-ray and after 2 months with clinical examination and assessment by Knee Society Score (KSS). Blood loss was detected by adding the values calculated in the operative room and the blood loss in the vacuum systems. In the study group, mean value of KSS was 85.2 (IC 95% 81.2-88.5), mean blood loss was 657 ml (IC 95% 580.6-735.4), and mean value of femorotibial angle was 178.8° (IC 95% 178.5-179.3). In the control group, mean value of KSS was 87.2 (IC 95% 85.3-89.4), mean blood loss was 866.5 ml (IC 95% 763.3-972.5), and mean value of femorotibial angle was 178.9°(IC 95% 177.6-180.3). The Student t test detected a significant difference in blood loss between groups (p < 0.05), and no differences were found between KSS. The single-use instrumentation should improve precision, operative time, turnover time, sterilization and maintenance costs and could help to reduce infection risks. Our results confirm only the improvement on reducing blood loss. In our opinion, this technique should be used in selected patients when the surgeon could have some difficulties to perform femoral cuts on coronal plane or when patients need to have a very little blood loss due to other conditions.


Assuntos
Artroplastia do Joelho/instrumentação , Perda Sanguínea Cirúrgica/prevenção & controle , Mau Alinhamento Ósseo/prevenção & controle , Modelagem Computacional Específica para o Paciente , Cirurgia Assistida por Computador/instrumentação , Idoso , Articulação do Tornozelo/diagnóstico por imagem , Antropometria , Feminino , Marcadores Fiduciais , Articulação do Quadril/diagnóstico por imagem , Humanos , Articulação do Joelho/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Prospectivos , Índice de Gravidade de Doença , Cirurgia Assistida por Computador/métodos
7.
J Synchrotron Radiat ; 25(Pt 6): 1745-1752, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-30407185

RESUMO

The combination of complementary techniques in the characterization of catalysts under working conditions is a very powerful tool for an accurate and in-depth comprehension of the system investigated. In particular, X-ray absorption spectroscopy (XAS) coupled with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and mass spectroscopy (MS) is a powerful combination since XAS characterizes the main elements of the catalytic system (selecting the absorption edge) and DRIFTS monitors surface adsorbates while MS enables product identification and quantification. In the present manuscript, a new reactor cell and an experimental setup optimized to perform time-resolved experiments on heterogeneous catalysts under working conditions are reported. A key feature of this setup is the possibility to work at high temperature and pressure, with a small cell dead volume. To demonstrate these capabilities, performance tests with and without X-rays are performed. The effective temperature at the sample surface, the speed to purge the gas volume inside the cell and catalytic activity have been evaluated to demonstrate the reliability and usefulness of the cell. The setup capability of combining XAS, DRIFTS and MS spectroscopies is demonstrated in a time-resolved experiment, following the reduction of NO by Rh nanoparticles supported on alumina.

8.
J Biol Regul Homeost Agents ; 31(4 suppl 1): 107-111, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29186946

RESUMO

Allografts techniques remain the best reconstructive strategy for chronic extensor mechanism lesions after total knee arthroplasty (3) but outcomes depend strictly on the host tissue-allograft junctions healing. The purpose of this study is to evaluate if modern techniques of adding autologous bone marrow cells concentrate enriched with platelet-rich fibrin, provide better healing of the allograft. We present the case of an 86 years old patient affected by patellar tendon rupture after TKA. A whole extensor mechanism allograft was performed adding a bone marrow cells concentrate enriched with platelet-rich fibrin on the host tissue-allograft junctions. Preoperatively and at each follow-up the value of Knee Society Score and radiographic consolidation signs were recorded. Radiographic controls showed clear signs of consolidation already at 1 months follow-up and a solid fusion at 3 months. This case report describes a valid method to improve healing using a tissue-construct engineered with stem cells and growth factors.

9.
Phys Chem Chem Phys ; 19(40): 27489-27507, 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-28975938

RESUMO

An X-ray absorption spectroscopy study of the UiO-67 Pt functionalized metal organic frameworks (MOFs) demonstrates that under appropriate conditions, at least two types of catalytically active sites can be formed in the cavities of the MOF: isolated Pt-complexes and Pt nanoparticles (Pt-NPs). Both pre-made linker synthesis (PMLS) and post-synthesis functionalization (PSF) methods were adopted. XAS was used to monitor the temperature-dependent behaviour of UiO-67-Pt while heating from RT to 623 K, in different gas feeds (pure He, 3% H2/He and 10% H2/He). We collected static in situ Pt LIII XANES and EXAFS spectra at room temperature (RT) before and after the thermal treatment, as well as spectra acquired under operando conditions upon heating. Under 10% H2/He thermal treatment, we unambiguously detected Pt-NP formation which has been followed by a parametric EXAFS analysis of the data collected during temperature programmed H2-reduction (TPR), using the Einstein model to predict the temperature dependence of the Debye-Waller factors. Conversely, in pure He flow, the only significant change observed during TPR is the progressive decrease of the Pt-Cl single scattering contribution, leading to the conclusion that the Pt grafted to the bpydc-linkers remains naked. Advanced EXAFS/TEM analysis allowed us to quantify the fraction of Pt in the form of Pt-NPs, values that have been quantitatively confirmed by linear combination analysis of the XANES spectra. In situ XANES/EXAFS study was supported by ex situ XRPD and BET analyses, confirming the framework stability and testifying a loss of the internal volume after TPR due to the formation of Pt-NPs insides the MOF pores, more relevant in the sample where smaller Pt-NPs were formed.

10.
J Chem Phys ; 147(4): 044503, 2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-28764363

RESUMO

Extended X-ray absorption fine structure (EXAFS) is a powerful probe of the distribution of nearest-neighbour distances around selected atomic species. We consider here the effect of vibrational disorder in crystals. The potential of EXAFS for the accurate evaluation of the coefficient of bond thermal expansion and its temperature dependence is discussed, with the aim of stimulating and facilitating the comparison with the results from total scattering experiments. The meaning of the distribution asymmetry in crystals and its connection with the effective potential anharmonicity and the bond expansion is quantitatively explored by comparing the results for a number of different systems. The extent of the relative atomic vibrations perpendicular to the bond direction and the perpendicular to parallel anisotropy are correlated with the extent of lattice negative thermal expansion as well as with the ionic mobility in superionic crystals.

11.
Faraday Discuss ; 201: 265-286, 2017 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-28621776

RESUMO

The exceptional thermal and chemical stability of the UiO-66, -67 and -68 classes of isostructural MOFs [J. Am. Chem. Soc., 2008, 130, 13850] makes them ideal materials for functionalization purposes aimed at introducing active centres for potential application in heterogeneous catalysis. We previously demonstrated that a small fraction (up to 10%) of the linkers in the UiO-67 MOF can be replaced by bipyridine-dicarboxylate (bpydc) moieties exhibiting metal-chelating ability and enabling the grafting of Pt(ii) and Pt(iv) ions in the MOF framework [Chem. Mater., 2015, 27, 1042] upon interaction with PtCl2 or PtCl4 precursors. Herein we extend this functionalization approach in two directions. First, we show that by controlling the activation of the UiO-67-Pt we can move from a material hosting isolated Pt(ii) sites anchored to the MOF framework with Pt(ii) exhibiting two coordination vacancies (potentially interesting for C-H bond activation) to the formation of very small Pt nanoparticles hosted inside the MOF cavities (potentially interesting for hydrogenation reactions). The second direction consists of the extension of the approach to the insertion of Cu(ii), obtained via interaction with CuCl2, and exhibiting interesting redox properties. All materials have been characterized by in situ X-ray absorption spectroscopy at the Pt L3- and Cu K-edges.

12.
J Synchrotron Radiat ; 23(1): 353-68, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26698085

RESUMO

The European Synchrotron Radiation Facility has recently made available to the user community a facility totally dedicated to Time-resolved and Extreme-conditions X-ray Absorption Spectroscopy--TEXAS. Based on an upgrade of the former energy-dispersive XAS beamline ID24, it provides a unique experimental tool combining unprecedented brilliance (up to 10(14) photons s(-1) on a 4 µm × 4 µm FWHM spot) and detection speed for a full EXAFS spectrum (100 ps per spectrum). The science mission includes studies of processes down to the nanosecond timescale, and investigations of matter at extreme pressure (500 GPa), temperature (10000 K) and magnetic field (30 T). The core activities of the beamline are centered on new experiments dedicated to the investigation of extreme states of matter that can be maintained only for very short periods of time. Here the infrastructure, optical scheme, detection systems and sample environments used to enable the mission-critical performance are described, and examples of first results on the investigation of the electronic and local structure in melts at pressure and temperature conditions relevant to the Earth's interior and in laser-shocked matter are given.

13.
Int J Sports Med ; 35(13): 1072-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25144434

RESUMO

This study evaluated the effects of 2 different types of acute aerobic exercise on the osmotic stability of human erythrocyte membrane and on different hematological and biochemical variables that are associated with this membrane property. The study population consisted of 20 healthy and active men. Participants performed single sessions of 2 types of exercise. The first session consisted of 60 min of moderate-intensity continuous exercise (MICE). The second session, executed a week later, consisted of high-intensity interval exercise (HIIE) until exhaustion. The osmotic stability of the erythrocyte membrane was represented by the inverse of the salt concentration (1/H50) at the midpoint of the sigmoidal curve of dependence between the absorbance of hemoglobin and the NaCl concentration. The values of 1/H50 changed from 2.29±0.1 to 2.33±0.09 after MICE and from 2.30±0.08 to 2.23±0.12 after HIIE. During MICE mean corpuscular volume increased, probably due to in vivo lysis of older erythrocytes, with preservation of cells that were larger and more resistant to in vitro lysis. The study showed that a single bout of acute exercise affected erythrocyte stability, which increased after MICE and decreased after HIIE.


Assuntos
Membrana Eritrocítica/fisiologia , Exercício Físico/fisiologia , Adulto , Glutationa Peroxidase/sangue , Testes Hematológicos , Humanos , Masculino , Fragilidade Osmótica , Adulto Jovem
14.
J Clin Ultrasound ; 42(2): 116-20, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23657871

RESUMO

Atherosclerotic renal artery stenosis is a frequent cause of arterial hypertension and/or allograft dysfunction after kidney transplantation and is usually located at the iliac artery anastomosis. Fibromuscular dysplasia is a less frequent, nonatherosclerotic, vascular disease, inducing stenosis at the proximal/mid-distal part of the renal artery. We report the case of a 44-year-old woman, in whom serum creatinine concentration increased and arterial hypertension developed 3 months after renal transplantation. Color Doppler ultrasonography showed a low arterial resistance index and prolonged acceleration time in the interlobar arteries, and a significantly increased peak systolic velocity at the mid third of the renal artery, demonstrating hemodynamically significant stenosis. Percutaneous transluminal angioplasty allowed stenosis correction and was followed by creatinine concentration and arterial blood pressure normalization.


Assuntos
Displasia Fibromuscular/diagnóstico por imagem , Transplante de Rim , Complicações Pós-Operatórias/diagnóstico por imagem , Obstrução da Artéria Renal/diagnóstico por imagem , Ultrassonografia Doppler em Cores , Adulto , Feminino , Displasia Fibromuscular/etiologia , Humanos , Obstrução da Artéria Renal/etiologia , Doadores de Tecidos
15.
Mol Phylogenet Evol ; 65(2): 739-47, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22877642

RESUMO

Cunila species are aromatic and medicinal plants commonly employed in folk medicine. This genus is distributed in North America and in southern South America. The species that occur in southern South America are classified into three botanical sections: Incanae, Incisae and Spicatae. The present study uses a phylogenetic approach to study the genetic relationship among the South and North American Cunila species, aiming to test the monophyly of the genus in its traditional circumscription. The results based on sequencing from nuclear (ITS rDNA) and chloroplast (trnL-F) sets did not agree with the traditional circumscription of the genus. These data, based on maximum parsimony, maximum likelihood and Bayesian analyses, point to the non-monophyletic status of Cunila, since the genus was separated into three segregated clades: (1) A South American subshrub clade formed by the species of the botanical section Spicatae, (2) a South American shrub clade that includes the species of the botanical sections Incanae and Incisae, and (3) a North American Cunila clade.


Assuntos
DNA Espaçador Ribossômico/genética , Lamiaceae/classificação , Filogenia , Teorema de Bayes , Núcleo Celular/genética , DNA de Cloroplastos/genética , DNA de Plantas/genética , Lamiaceae/genética , Funções Verossimilhança , Modelos Genéticos , América do Norte , Análise de Sequência de DNA , América do Sul
16.
ScientificWorldJournal ; 2012: 790486, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22593706

RESUMO

Supercritical fluid extraction has been widely employed in the extraction of high purity substances. In this study, we used the technology to obtain oil from seeds from a variety of grapes, from vinification residues generated in the Southern region of the state of Rio Grande do Sul, Brazil. This work encompasses three varieties of Vitis vinifera (Moscato Giallo, Merlot, and Cabernet Sauvignon) and two of Vitis labrusca (Bordô e Isabel), harvested in 2005 and 2006. We obtained the highest oil content from Bordô (15.40%) in 2005 and from Merlot (14.66%), 2006. The biggest concentration of palmitic, stearic, and linoleic acids was observed in Bordô, 2005, and in Bordô, Merlot, and Moscato Giallo, 2006. Bordô showed the highest concentration of oleic acid and α-tocopherol in both seasons too. For the equivalent of procyanidins, we did not notice significant difference among the varieties from the 2005 harvest. In 2006, both varieties Isabel and Cabernet Sauvignon showed a value slightly lower than the other varieties. The concentration of total phenolics was higher in Bordô and Cabernet Sauvignon. The presence of these substances is related to several important pharmacological properties and might be an alternative to conventional processes to obtain these bioactives.


Assuntos
Cromatografia com Fluido Supercrítico/métodos , Ácidos Graxos/análise , Fenóis/análise , Sementes/química , Vitis/química , alfa-Tocoferol/análise , Brasil , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Ácidos Linoleicos/análise , Ácido Palmítico/análise , Óleos de Plantas/química , Proantocianidinas/análise , Especificidade da Espécie , Ácidos Esteáricos/análise , Vitis/classificação , Vinho
17.
Arch Pediatr ; 17(7): 1008-16, 2010 Jul.
Artigo em Francês | MEDLINE | ID: mdl-20409697

RESUMO

PURPOSE: Morphologic abnormalities of the hippocampal formations (MAHF) are more frequently observed in magnetic resonance imaging (MRI). We wished to specify the types of disorders associated with these malformations based on a retrospective case series by studying the language of the children presenting these abnormalities. PATIENTS AND METHODS: From the data of all the MRIs taken in the neuroradiology ward of our center over 16 months in patients under 18 years of age, we retrospectively selected the children with an MAHF, isolated or associated with other malformations. The MAHFs were defined and described according to criteria of shape or orientation defects of the hippocampal formations. We studied the files of the patients with isolated MAHF again. Those whose clinical presentation was compatible with language assessment were tested in a prospective approach. RESULTS: Out of 2208 MRIs from 1 January 2007 to 30 April 2008, 96 (4.3%) showed an MAHF, including 61 (64%) boys and 35 (36%) girls, aged from 2 months to 17 years. Eighty-two (85%) had associated abnormalities, mainly including cerebral atrophy, corpus callosum agenesis or defect, and abnormal ventricular frontal horns. Fourteen (15%) had an isolated MAHF: 2 on the left hemisphere, 2 on the right hemisphere, and 10 on both. Of these 14, 9 were compatible with language assessment. From the test results, we divided these children into 2 groups, depending on the type and severity of the impairment. Four had very serious language disorders as part of mental retardation or autistic disorders; 4 others had language disorders predominantly in expression and phonology, with weak to pathological visual memory. This study showed no potential relation between the lateralization of MAHF and language disorders, nor between the existence of epilepsy and the severity of the language disorders. Of these 14 children, 9 had behavior and autism spectrum disorders and 7 were epileptic. CONCLUSION: Even though language disorders are often part of a larger deficiency presentation, the results we obtained suggest that isolated MAHFs are not only causes of amnestic disorders, but they could also directly underlie language disorders, particularly in expression.


Assuntos
Hipocampo/anormalidades , Hipocampo/patologia , Transtornos da Linguagem/diagnóstico , Imageamento por Ressonância Magnética , Adolescente , Transtorno Autístico/diagnóstico , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Deficiência Intelectual/diagnóstico , Transtornos da Linguagem/etiologia , Masculino , Estudos Retrospectivos
18.
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.

19.
G Ital Med Lav Ergon ; 29(3 Suppl): 859-60, 2007.
Artigo em Italiano | MEDLINE | ID: mdl-18410002

RESUMO

The purpose of this study is to value the advantage of open fitting ear-moulds in tecnopathic ipoacusies. The study was conducted on a sample of 70 tecnopathic ipoacusics with a hearing loss in the high wave frequencies (4000-8000 Hz) ammounting to at least 50 dB; 20 of which already using ear-moulds. To all of them was applied, for three weeks, an open fitting ear-mould. At the beginning and at the end of the study, the sample was given a questionary to fill out. The analysis of the questionnaries has proven that among the 20 tecnopathics already using ear-moulds: A) 16 subjects have a marked preference for the open fitting ear-moulds, B) 3 did not encounter differences between the two types of ear-moulds, C) 1 declared a better adaptability to the previous ear-moulds. Over all, in the 70 subjects examined, this research's results allow us to conclude that: the use of open fitting ear-moulds improves the quality of the natural sound of one's own voice, the natural quality of sounds, and the hearing of speech in the presence of other noises, while reducing irritation of the auditory cortex.


Assuntos
Auxiliares de Audição , Perda Auditiva/terapia , Satisfação do Paciente , Adulto , Desenho de Equipamento , Humanos , Pessoa de Meia-Idade
20.
J Agric Food Chem ; 49(9): 4220-3, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11559114

RESUMO

The essential oil composition and genetic variability of six commercial cultivars of thyme (Thymus vulgaris L.), a Mediterranean medicinal and aromatic plant, were analyzed by GC-MS and randomly amplified polymorphic DNA (RAPD), respectively. All evaluated cultivars belong to the thymol chemotype, with differences in the concentrations of thymol, gamma-terpinene, p-cymene, and other minor components. The comparison of the oil components concentration by multivariate analysis allowed separation of the cultivars into two groups. All of the cultivars exhibited characteristic RAPD patterns that allowed their identification. On the basis of the RAPD patterns, the cultivars could be divided into two clusters, which coincides with results obtained by oil GS-MS analysis, with a correlation coefficient of -0.779.


Assuntos
DNA de Plantas/análise , Lamiaceae/química , Lamiaceae/genética , Óleos Voláteis/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos Voláteis/análise , Técnica de Amplificação ao Acaso de DNA Polimórfico/métodos
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