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1.
J Laryngol Otol ; 137(5): 524-531, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35791849

RESUMO

OBJECTIVE: This study aimed to determine the predictors of olfactory improvement after endoscopic sinus surgery among patients with chronic rhinosinusitis with nasal polyps. METHOD: This prospective cohort study included patients admitted to a university hospital between 2006 and 2012. Assessment using odour identification testing, a sinonasal symptom questionnaire, the Rhinosinusitis Disability Index and mucus biomarker levels was performed at various time points. Correlation of variables with identification score differences at six post-operative time points and at baseline was performed, followed by multiple linear regression to determine significant predictors at each of the six post-operative time points. RESULTS: Baseline absence of acute sinusitis, elevated serpin F2 and anterior rhinorrhoea predict early olfactory improvement, whereas baseline allergic rhinitis predicts late olfactory improvement. Baseline odour identification score was the strongest predictor across all time points. CONCLUSION: Patients with chronic rhinosinusitis and nasal polyps with worse disease or baseline olfactory function may benefit more from endoscopic sinus surgery in terms of olfactory improvement.


Assuntos
Pólipos Nasais , Rinite , Sinusite , Humanos , Pólipos Nasais/complicações , Pólipos Nasais/cirurgia , Estudos Prospectivos , Rinite/complicações , Rinite/cirurgia , Sinusite/complicações , Sinusite/cirurgia , Endoscopia , Olfato , Doença Crônica
2.
J Interv Card Electrophysiol ; 65(2): 491-497, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35748975

RESUMO

BACKGROUND: High-power short-duration (HPSD) radiofrequency ablation (RFA) is highly efficient and safe while reducing procedure and RF time in pulmonary vein isolation (PVI). The QDot™ catheter is a novel contact force ablation catheter that allows automated flow and power adjustments depending on the local tissue temperature to maintain a target temperature during 90 W/4 s lesions. We analysed intraprocedural data and periprocedural safety using the QDot-catheter in patients undergoing PVI for paroxysmal atrial fibrillation (PAF). METHODS: We included n = 48 patients undergoing PVI with the QDot-catheter with a temperature-controlled HPSD ablation mode with 90 W/4 s (TC-HPSD). If focal reconnection occurred besides repeat ablation, the ablation mode was changed to 50 W/15 s (QMode). N = 23 patients underwent cerebral MRI to detect silent cerebral lesions. RESULTS: Mean RF time was 8.1 ± 2.8 min, and procedure duration was 84.5 ± 30 min. The overall maximal measured catheter tip temperature was 52.0 °C ± 4.6 °C, mean overall applied current was 871 mA ± 44 mA and overall applied energy was 316 J ± 47 J. The mean local impedance drop was 12.1 ± 2.4 Ohms. During adenosine challenge, n = 14 (29%) patients showed dormant conduction. A total of n = 24 steam pops were detected in n = 18 patients (39.1%), while no pericardial tamponade occurred. No periprocedural thromboembolic complications occurred, while n = 4 patients (17.4%) showed silent cerebral lesion. CONCLUSIONS: TC-HPSD ablation with 90 W/4 s using the QDot-catheter led to a reduction of procedure and RF time, while no major complications occurred. Despite optimized temperature control and power adjustment, steam pops occurred in a rather high number of patients, while none of them leads to tamponade or to clinical or neurological deficits.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Humanos , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/cirurgia , Temperatura , Vapor , Desenho de Equipamento , Ablação por Cateter/métodos , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Fibrilação Atrial/etiologia , Imageamento por Ressonância Magnética , Resultado do Tratamento
3.
Plant Biol (Stuttg) ; 24(7): 1240-1253, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35611757

RESUMO

Climate change is expected to increase the frequency and intensity of summer droughts. Sufficient drought resistance, the ability to acclimate to and/or recover after drought, is thus crucial for forest tree species. However, studies on the hydraulics of mature trees during and after drought in natura are scarce. In this study, we analysed trunk water content (electrical resistivity: ER) and further hydraulic (water potential, sap flow density, specific hydraulic conductivity, vulnerability to embolism) as well as wood anatomical traits (tree ring width, conduit diameter, conduit wall reinforcement) of drought-stressed (artificially induced summer drought via throughfall-exclusion) and unstressed Picea abies and Fagus sylvatica trees. In P. abies, ER indicated a strong reduction in trunk water content after 5 years of summer drought, corresponding to significantly lower pre-dawn leaf water potential and xylem sap flow density. Vulnerability to embolism tended to be higher in drought-stressed trees. In F. sylvatica, only small differences between drought-stressed and control trees were observed. Re-watering led to a rapid increase in water potentials and xylem sap flow of both drought-stressed trees, and to increased growth rates in the next growing season. ER analyses revealed lower trunk water content in P. abies trees growing on throughfall-exclusion plots even 1 year after re-watering, indicating a limited capacity to restore internal water reserves. Results demonstrated that P. abies is more susceptible to recurrent summer drought than F. sylvatica, and can exhibit long-lasting and pronounced legacy effects in trunk water reserves.


Assuntos
Abies , Fagus , Picea , Pinus , Secas , Estações do Ano , Árvores , Água
4.
Vet Parasitol Reg Stud Reports ; 28: 100678, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35115118

RESUMO

Bovine parafilariosis is an emerging fly-borne disease in central Europe, characterized by seasonal occurrence of hemorrhagic exudations ('bleeding spots') from the end of winter to end of summer. In two cases from Germany reported here, one animal of a small herd in Bavaria and 20 animals on a farm in Baden-Württemberg presented bleeding spots from late March and late April 2020, respectively. Exudate samples from both cases were positive for larvated Parafilaria eggs. Examination of the skin and trimmed tissue after slaughter of the animal from Bavaria resulted in the collection of 11 nematodes (two males, eight females, one specimen in fragments). The animal's carcass presented typical yellow-greenish areas and bloody spots on the subcutaneous tissue of the flesh side of the skin. The nematodes were microscopically determined as Parafilaria bovicola. Basic morphometric measurements of two (one intact) male and six female nematodes are within the ranges of published data; length (male/female) 28.8/48.0-64.5 mm; width, 397.6 µm/430.7-527.6 µm; distance of cervical papillae to anterior end, 177.6/248.9-337.4; left spiculum/right spiculum (male), 365.3-379.4/149.5-180.3 µm; gubernaculum 45.0-48.1 µm; distance of vulva to anterior end (female), 37.3-66.0 mm. In order to gain information on P. bovicola in its vector, 91 cattle-visiting Musca autumnalis flies were collected from the affected animal in Bavaria (36 flies) and from co-pastured animals (55 flies) for PCR analysis and sequencing. A total of 14 flies were PCR-positive for filarial DNA, and sequencing of a fragment of the cox1 gene resulted in identification of P. bovicola (n = 10) and Thelazia gulosa (n = 5). This report presents further cases of bovine parafilariosis in Germany, provides morphometric data on male and female P. bovicola nematodes retrieved from cattle and identified DNA of P. bovicola and T.gulosa in M. autumnalis flies collected at a site of occurrence of bovine parafilariosis.


Assuntos
Doenças dos Bovinos , Filarioidea , Muscidae , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/epidemiologia , Europa (Continente) , Feminino , Alemanha/epidemiologia , Masculino
5.
Plant Pathol ; 67(5): 1122-1130, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29861507

RESUMO

High elevation spruce forests of the European Alps are frequently infected by the needle rust Chrysomyxa rhododendri, a pathogen causing remarkable defoliation, reduced tree growth and limited rejuvenation. Exact quantification of the disease severity on different spatial scales is crucial for monitoring, management and resistance breeding activities. Based on the distinct yellow discolouration of attacked needles, it was investigated whether image analysis of digital photographs can be used to quantify disease severity and to improve phenotyping compared to conventional assessment in terms of time, effort and application range. The developed protocol for preprocessing and analysis of digital RGB images enabled identification of disease symptoms and healthy needle areas on images obtained in ground surveys (total number of analysed images n = 62) and by the use of a semiprofessional quadcopter (n = 13). Obtained disease severities correlated linearly with results obtained by manual counting of healthy and diseased needles for all approaches, including images of individual branches with natural background (R2 = 0.87) and with black background (R2 = 0.95), juvenile plants (R2 = 0.94), and top views and side views of entire tree crowns of adult trees (R2 = 0.98 and 0.88, respectively). Results underline that a well-defined signal related to needle bladder rust symptoms of Norway spruce can be extracted from images recorded by standard digital cameras and using drones. The presented protocol enables precise and time-efficient quantification of disease symptoms caused by C. rhododendri and provides several advantages compared to conventional assessment by manual counting or visual estimations.

6.
J Microsc ; 263(2): 192-9, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27075881

RESUMO

Aeroterrestrial green algae are exposed to desiccation in their natural habitat, but their actual volume changes have not been investigated. Here, we measure the relative volume reduction (RVRED ) in Klebsormidium crenulatum and Zygnema sp. under different preset relative air humidities (RH). A new chamber allows monitoring RH during light microscopic observation of the desiccation process. The RHs were set in the range of ∼4 % to ∼95% in 10 steps. RVRED caused by the desiccation process was determined after full acclimation to the respective RHs. In K. crenulatum, RVRED (mean ± SE) was 46.4 ± 1.9%, in Zygnema sp. RVRED was only 34.3 ± 2.4% at the highest RH (∼95%) tested. This indicates a more pronounced water loss at higher RHs in K. crenulatum versus Zygnema sp. By contrast, at the lowest RH (∼4%) tested, RVRED ranged from 75.9 ± 2.7% in K. crenulatum to 83.9 ± 2.2% in Zygnema sp. The final volume reduction is therefore more drastic in Zygnema sp. These data contribute to our understanding of the desiccation process in streptophytic green algae, which are considered the closest ancestors of land plants.


Assuntos
Clorófitas/metabolismo , Dessecação , Microscopia/métodos , Estreptófitas/metabolismo , Clorófitas/citologia , Umidade , Estreptófitas/citologia , Água/análise
7.
Nanoscale ; 8(17): 9398-404, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27093061

RESUMO

Nanocomposites constitute an upcoming class of materials that has enormous potential within a broad range of areas, particularly with regard to mechanical applications. However, the tuning of material properties requires a full understanding of the mechanical response of the nanocomposite across all length scales. While characterization from the micro to macroscale is well established at this point, quantification of mechanical behavior at the nanoscale is still an unresolved challenge. With this background, the current work demonstrates the capabilities of quantitative contact resonance atomic force microscopy (CR-AFM) to localize and reliably characterize Ni nanoparticles that are embedded below the surface of thermally oxidized silicon thin films. Correlating these results with numerical simulations as well as high-resolution transmission electron microscopy measurements provides a comprehensive understanding of the subtle interplay between the structure and nanomechanical response of the composite.

8.
Soft Matter ; 11(25): 5053-9, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26027952

RESUMO

Cells require adhesion to survive, proliferate and migrate, as well as for wound healing and many other functions. The strength of contractile cell forces on an underlying surface is a highly relevant quantity to measure the affinity of cells to a rigid surface with and without coating. Here we show with experimental and theoretical studies that these forces create surface stresses that are sufficient to induce measurable bending of macroscopic cantilevers. Since contractile forces are linked to the formation of focal contacts, results give information on adhesion promoting qualities and allow a comparison of very diverse materials. In exemplary studies, in vitro fibroblast adhesion on the magnetic shape memory alloy Fe-Pd and on the l-lysine derived plasma-functionalized polymer PPLL was determined. We show that cells on Fe-Pd are able to induce surface stresses three times as high as on pure titanium cantilevers. A further increase was observed for PPLL, where the contractile forces are four times higher than on the titanium reference. In addition, we performed finite element simulations on the beam bending to back up the calculation of contractile forces from cantilever bending under non-homogenous surface stress. Our findings consolidate the role of contractile forces as a meaningful measure of biomaterial performance.


Assuntos
Ligas/química , Materiais Biocompatíveis/química , Fibroblastos/citologia , Ferro/química , Teste de Materiais/instrumentação , Paládio/química , Polilisina/química , Animais , Adesão Celular , Técnicas de Cultura de Células/instrumentação , Desenho de Equipamento , Análise de Elementos Finitos , Fenômenos Mecânicos , Camundongos , Células NIH 3T3 , Gases em Plasma/química , Polímeros/química , Estresse Mecânico , Propriedades de Superfície
9.
Nanotechnology ; 26(12): 125704, 2015 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-25736739

RESUMO

Surface stresses lead to an effective change in the elastic constants of thin films and at surfaces. The development of modern scanning probe techniques like contact resonance atomic force microscopy empowers the experimenter to measure at scales where these effects become increasingly relevant. In this paper we employ a computational multiscale approach where we compare density functional theory (DFT) and molecular dynamics simulations as tools to calculate the thin-film/surface elastic behavior for silicon and strontiumtitanate. From the surface elastic constants gained by DFT calculations we develop a continuum finite-element multilayer model to study the impact of surface stresses on indentation experiments. In general the stress field of an indenter and thus the impact of surface stresses on the indentation modulus depends on its contact radius and on its particular shape. We propose an analytical model that describes the behavior of the indentation modulus as a function of the contact radius. We show that this model fits well to simulation results gained for a spherical and a flat punch indenter. Our results demonstrate a surface-stress-induced reduction of the indentation modulus of about 5% for strontiumtitanate and 6% for silicon for a contact radius of [Formula: see text], irrespective of the indenter shape.

10.
Nanoscale ; 6(12): 6898-910, 2014 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-24838534

RESUMO

Contact resonance atomic force microscopy (CR-AFM) constitutes a powerful approach for nanometer-resolved mechanical characterization of surfaces. Yet, absolute accuracy is frequently impaired by ad hoc assumptions on the dynamic AFM cantilever characteristics as well as contact model. Within the present study, we clarify the detailed interplay of stress fields and geometries for full quantitative understanding, employing combined experimental numerical studies for real AFM probes. Concerning contact description, a two-parameter ansatz is utilized that takes tip geometries and their corresponding indentation moduli into account. Parameter sets obtained upon experimental data fitting for different tip blunting states, are discussed in terms of model-specific artificiality versus real contact physics at the nanoscale. Unveiling the underlying physics in detail, these findings pave the way for accurate characterization of nanomechanical properties with highest resolution.

11.
Beilstein J Nanotechnol ; 5: 466-75, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24778973

RESUMO

Magnetically anisotropic as well as magnetic core-shell nanoparticles (CS-NPs) with controllable properties are highly desirable in a broad range of applications. With this background, a setup for the synthesis of heterostructured magnetic core-shell nanoparticles, which relies on (optionally pulsed) DC plasma gas condensation has been developed. We demonstrate the synthesis of elemental nickel nanoparticles with highly tunable sizes and shapes and Ni@Cu CS-NPs with an average shell thickness of 10 nm as determined with scanning electron microscopy, high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy measurements. An analytical model that relies on classical kinetic gas theory is used to describe the deposition of Cu shell atoms on top of existing Ni cores. Its predictive power and possible implications for the growth of heterostructured NP in gas condensation processes are discussed.

12.
Artigo em Inglês | MEDLINE | ID: mdl-27631027

RESUMO

Water transport in plants is based on a metastable system as the xylem "works" at negative water potentials (ψ). At critically low ψ, water columns can break and cause embolism. According to the air-seeding hypothesis, this occurs by air entry via the pits. We studied the formation of embolism in dehydrating xylem sections of Juniperus virginiana (Cupressaceae), which were monitored microscopically and via ultrasonic emission analyses. After replacement of water by air in outer tracheid layers, a complex movement of air-water menisci into tracheids was found. With decreasing ψ, pits started to aspirate and the speed of menisci movements increased. In one experiment, an airseeding event could be detected at a pit. The onset of ultrasonic activity was observed when pits started to close, and ultrasonic emission ceased at intense dehydration. Experiments clearly indicated that predictions of the air-seeding hypothesis are correct: At low ψ, pit mechanisms to prevent air entry failed and air spread into tracheids. ψ fluctuations caused complex movements of air-water menisci and pits, and at low ψ, air-seeding caused ultrasonic emissions. Main insights are presented in a video.

13.
J Mater Chem B ; 2(44): 7739-7746, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-32261910

RESUMO

When bringing functional hard materials to biomedical applications, control of interfaces with cells and tissue poses one of the largest challenges. Assembly of protein monomers within an inert-gas-plasma constitutes a novel approach to synthesize strongly adherent bioactive coatings that dramatically enhance coupling to living matter. As proof of concept this is demonstrated for a Fe-Pd ferromagnetic shape memory transducer that is functionalized with the amino-acid, l-lysine, by plasma-treatment, resulting in flexible, yet ultra-durable coatings. Containing high amounts of NH2 functional groups, they fulfill all requirements for strong adhesion of cells and tissues. This is confirmed by cell tests with living NIH/3T3 embryonic murine fibroblasts that demonstrate excellent biocompatibility, exceeding conventional poly-l-lysine coatings in terms of cells focal adhesion density. The physics and chemistry behind these scenarios are unraveled by employing ab initio computer calculations. This combined approach opens the way for plasma-assisted functionalization strategies for a broad class of metals and semiconductors with polypeptides.

14.
Trees (Berl West) ; 27(3): 707-715, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23794789

RESUMO

Lammas shoots are flushes formed by some woody species later in the growing season. Having less time to develop, tissue formation is suggested to be incomplete leading to a higher peridermal water loss during consecutive months. In this study, we analysed morphological and anatomical parameters, peridermal conductance to water vapour and the level of native embolism in mid-winter and late-winter of lammas shoots and normal spring shoots of the apple varieties Malus domestica 'Gala' and 'Nicoter'. Lammas shoots showed a significantly higher shoot cross-sectional area due to larger pith and corticular parenchyma areas. In contrast, phloem was significantly thicker in spring shoots. No pronounced differences were observed in xylem and collenchyma thickness or mean hydraulic conduit diameter. The phellem of spring shoots was composed of more suberinised cells compared to lammas shoots, which led to a significantly higher peridermal conductance in the latter. The amount of native embolism in mid-winter did not differ between shoot types, but in late-winter lammas shoots were more embolised than spring shoots. Data show that the restricted vegetation period of lammas shoots affects their development and, in consequence, their transpiration shield. This may also pose a risk for winter desiccation.

15.
Acta Biomater ; 9(3): 5845-53, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23131387

RESUMO

Ferromagnetic shape memory (FMSM) alloys constitute an exciting new class of smart materials that can yield magnetically switchable strains of several percent at constant temperatures and frequencies from quasi-static up to some kilohertz. In addition to their FMSM properties, these alloys can still be operated as conventional shape memory materials and also exhibit related superelasticity, which are both important features for use in medical devices. In this study, extensive in vitro assessments demonstrate for the first time that vapor-deposited single crystalline Fe(70)Pd(30) thin films and roughness graded polycrystalline splats of the same stoichiometry exhibit excellent biocompatibility and even bioactivity in contact with different cell types-a prerequisite for medical applications. The present study shows that fibroblast and epithelial cell lines, as well as primary osteoblast cells, proliferate well on Fe-Pd. The number of focal contacts, important for strong tissue bonding, can be improved with different binding agents from the extracellular matrix. However, even without coating, there is clear evidence that cells on Fe-Pd substrates behave similarly to control experiments. Additionally, cytotoxic effects of polycrystalline surfaces with various roughness profiles can be excluded, giving another tunable parameter for applying Fe-Pd magnetically switchable membranes in, e.g., stents and valves.


Assuntos
Tecnologia Biomédica/métodos , Materiais Revestidos Biocompatíveis/farmacologia , Ferro/farmacologia , Imãs/química , Teste de Materiais/métodos , Paládio/farmacologia , Proteínas/farmacologia , Animais , Adesão Celular/efeitos dos fármacos , Contagem de Células , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Fibronectinas/farmacologia , Humanos , Laminina/farmacologia , Camundongos , Microscopia Confocal , Células NIH 3T3 , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Propriedades de Superfície
16.
Phys Rev Lett ; 109(19): 195704, 2012 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-23215403

RESUMO

When processing Fe-Pd ferromagnetic shape memory thin films, selection of the desired phases and their transformation temperatures constitutes one of the largest challenges from an application point of view. In the present contribution we demonstrate that irradiation with 1.8 MeV Kr(+) ions is the method of choice to achieve this goal: Single crystalline Fe(7)Pd(3) thin films that are grown with molecular beam epitaxy on MgO (001) substrates and subsequently irradiated with ions reveal a phase transformation along the whole phase transformation path ranging from fcc austenite to bcc martensite. While for 10(14) ions/cm(2) a fcc-fct phase transformation is observed, increasing the fluence to 5 × 10(14) ions/cm(2) and 5 × 10(15) ions/cm(2) leads to a phase transformation to the bcc phase. Pole figure measurements reveal an orientation relationship for the fcc-bcc phase transformation according to Nishiyama and Wassermann.

17.
Adv Mater ; 24(18): 2399-403, 2012 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-22488713

RESUMO

Organotypic tissue cultures are highly promising for performing in vivo type studies in vitro. Currently, however, very limited survival times of only a few days for adult tissue often severely limit their application. Here, superhydrophilic nanostructured substrates with ideal material properties ensure tissue adhesion, essential for organotypic culture, while migration of single cells out of the tissue is hampered. Tuning substrate properties, for the first time, adult neuronal tissue could be cultured for 14 days with no indications of degeneration.


Assuntos
Neurônios/citologia , Animais , Células Cultivadas , Córtex Cerebral/citologia , Cobaias , Camundongos , Camundongos Endogâmicos C57BL , Nanotubos/química , Porosidade , Retina/citologia , Titânio/química
18.
Rev. chil. salud pública ; 16(2): 115-122, 2012. tab, ilus
Artigo em Espanhol | LILACS | ID: lil-712365

RESUMO

Objetivos: Para disponer de información desagregada de la situación nutricional y presencia de factores de riesgo cardiovascular de la mujer mapuche huilliche y conformar una línea diagnóstica que sirva de base para estudios posteriores e iniciativas que la incluyan, se estudió una muestra estadísticamente representativa de mujeres de esa etnia, jefas de hogar, de zonas rurales y urbanas de la Provincia de Osorno. Material y método: Se utilizó un diseño no experimental, transeccional y descriptivo. Resultados: Se encontró que un 48,8 por ciento presenta un IMC>30, superando en 18,1 puntos porcentuales el promedio nacional equivalente. Un 42,1 por ciento presenta obesidad abdominal (circunferencia cintura >83cm) y el 73,5 por ciento tiene valores de alto riesgo en las razones de cintura-cadera y de cintura-estatura. Se presenta la relación de estos indicadores con variables como edad, ruralidad, presión arterial y reporte de enfermedades crónicas no transmisibles. Conclusiones: Se encontró alta prevalencia de factores de riesgo cardiovascular y baja concordancia entre IMC y percepción de estado nutricional.


Objective: In order to make available disaggregated information on nutritional state and cardiovascular risk factors among Mapuche Huilliche women, and establish a baseline for future studies and initiatives, a statistically representative sample of MapucheHuilliche women, heads of households, in rural and urban areas in Osorno Province. Materials and Methods: A non-experimental, cross-sectional, descriptive study design was used. Results: 48 percent had a BMI>30, 18.1 percent higher than the national average. 42.1 percent showed abdominal obesity (waist circumference >83cm) and 73.5 percent showed high risk values of waist-hip and waist-height ratios. The relationship of these indicators to other variables such as age, rural residence, blood pressure and chronic non transmissible diseases is discussed. Conclusions: A high prevalence of cardiovascular risk was found, as well as low perception of nutritional state as related to BMI.


Assuntos
Humanos , Adulto , Feminino , Pessoa de Meia-Idade , Doenças Cardiovasculares/epidemiologia , Indígenas Sul-Americanos , Estado Nutricional , Pressão Arterial , Glicemia , Índice de Massa Corporal , Peso Corporal , Chile , Lipídeos/sangue , Fatores de Risco , Zona Rural , Área Urbana , Relação Cintura-Quadril
19.
Adv Mater ; 23(33): 3838-41, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21766348

RESUMO

In-plane mechanical response of TiO2 nano-tube arrays is intrinsically characterized by very low elastic moduli and significant damping, while both are strongly affected by presence of adsorbates. These findings suggest use of TiO2 nanotube arrays as novel types of sensors, actuators as well as highly stretchable coatings in biomedical applications.

20.
J Exp Bot ; 61(12): 3385-93, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20551085

RESUMO

The Cavitron technique facilitates time and material saving for vulnerability analysis. The use of rotors with small diameters leads to high water pressure gradients (DeltaP) across samples, which may cause pit aspiration in conifers. In this study, the effect of pit aspiration on Cavitron measurements was analysed and a modified 'conifer method' was tested which avoids critical (i.e. pit aspiration inducing) DeltaP. Four conifer species were used (Juniperus communis, Picea abies, Pinus sylvestris, and Larix decidua) for vulnerability analysis based on the standard Cavitron technique and the conifer method. In addition, DeltaP thresholds for pit aspiration were determined and water extraction curves were constructed. Vulnerability curves obtained with the standard method showed generally a less negative P for the induction of embolism than curves of the conifer method. Differences were species-specific with the smallest effects in Juniperus. Larix showed the most pronounced shifts in P(50) (pressure at 50% loss of conductivity) between the standard (-1.5 MPa) and the conifer (-3.5 MPa) methods. Pit aspiration occurred at the lowest DeltaP in Larix and at the highest in Juniperus. Accordingly, at a spinning velocity inducing P(50), DeltaP caused only a 4% loss of conductivity induced by pit aspiration in Juniperus, but about 60% in Larix. Water extraction curves were similar to vulnerability curves indicating that spinning itself did not affect pits. Conifer pit aspiration can have major influences on Cavitron measurements and lead to an overestimation of vulnerability thresholds when a small rotor is used. Thus, the conifer method presented here enables correct vulnerability analysis by avoiding artificial conductivity losses.


Assuntos
Traqueófitas/fisiologia , Água/análise , Centrifugação/métodos , Pressão , Água/fisiologia
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