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1.
Clin Oral Investig ; 27(7): 4039-4050, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37126145

RESUMO

OBJECTIVE: Whether it is primarily the spine that reacts with pain to the negative consequences of everyday stress and possibly the temporomandibular system as a result (ascending chain), or whether incorrect stress in the dental area has an influence on body geometry (descending chain), is still a controversially discussed topic. The aim of this study is to investigate possible relationships between constitutional, axiographic, and dental parameters with upper body posture. MATERIAL AND METHODS: A total of 106 subjectively healthy women between 31 and 40 years of age voluntarily participated in this study. Data collection was done by filling out a questionnaire with constitutional and anamnestic parameters and by evaluating orthodontic casts, axiographic measurements, and video raster stereographic measurements. These data were analyzed using correlations and group comparisons, with the significance level set at p ≤ 0.05. RESULTS: Positive correlations were shown between the constitutional factors of body weight and BMI and the lumbar bending angle (p = 0.01), the kyphosis angle (p = 0.001), and lordosis angle (weight p = 0.05; BMI p = 0.03). In the cast analysis, regardless of the direction of the midline shift (left/right/none), a left lateral tilt can be seen which is greatest at 2.12° with a left midline shift. In addition, the elevated pelvic side correlates with the side of the displacement of the jaw, with the stronger manifestation being on the left side. With a vertical anterior bite in the normal range, the kyphosis angle is 48.09°, while with a deep bite, it is 60.92°, and with an open bite, it is 62.47°; thus, the group in the normal range differs significantly (p = 0.01) from the other two. The greater the protrusion, the smaller the sagittal plane angles (kyphosis angle, lumbar bending angle, each p = 0.03), and the more dorsal the posture (p = 0.04). The lordosis angle differs significantly (p = 0.001) between the group of subjects with a protrusion in the normal range (52.34°) and the group with an increased advancement of the mandible (41.79°). CONCLUSION: There is a correlation between body weight, BMI, midline shift, and protrusion, as well as the vertical anterior step and upper body posture in women between 31 and 40 years of age. Interdisciplinary functional examinations of the temporomandibular musculature, and also sustained orthodontic treatment, can contribute to an improvement in upper body posture.


Assuntos
Cifose , Lordose , Humanos , Feminino , Adulto , Postura , Registro da Relação Maxilomandibular , Peso Corporal
2.
BMC Musculoskelet Disord ; 21(1): 636, 2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-32979920

RESUMO

BACKGROUND: Temporary occlusal changes and their influence on the upper body statics are still controversially discussed. Furthermore, concrete statements on whether age- or gender-specific differences in neurophysiological reactions exist are missing. Therefore, it is the aim of this study to evaluate the immediate effects of a symmetrical occlusion blocking on the upper body posture. These effects shall be investigated for both genders and for a larger age range. METHODS: In this study, 800 (407f/393 m) subjects volunteered aged from 21 to 60 years. Both genders were divided into four age groups according to decades. The three-dimensional upper body posture was measured by using the rasterstereography (ABW-Bodymapper). The habitual static posture was measured in two dental occlusion conditions (a) in rest position and (b) symmetrical blocking in the bicuspid region by cotton rolls. RESULTS: A significant reduction of the trunk length (0.72 mm; p <  0.001), an increase of the lumbar (0.30°; p <  0.001) and the thoracic bending angle (0.14°; p = 0.001), a reduction of the spinal forward decline (0.16°; p <  0.001) and a reduction of the scapular distance (0.36 mm; p = 0.001) was found. Gender-specific reactions can only be recorded in scapular distance, in that regard men reduce this distance while over all age groups women did not show a significant change. DISCUSSION: Slight gender- and age-independent reactions due to a symmetric occlusion blockade are shown: A gender independent reaction of the spinal related variables in the sagittal plane (thoracic and lumbar flexion angle, trunk length, spinal forward decline). In addition, a gender specific change of the shoulder blade distance could be observed, where men reduced the distance while female did not show a change. However, since these reactions are of a minimum amount, it can be concluded that neurophysiological compensation mechanisms work equally well regardless of age and sex, and the upper body posture of healthy people changes only very slightly due to a temporarily symmetrical altered bite position.


Assuntos
Postura , Coluna Vertebral , Adulto , Feminino , Humanos , Região Lombossacral , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Escápula , Adulto Jovem
3.
Sci Rep ; 13(1): 873, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650216

RESUMO

In order to classify and analyze the parameters of upper body posture in clinical or physiotherapeutic settings, a baseline in the form of standard values with special regard to age, sex and BMI is required. Thus, subjectively healthy men and women aged 21-60 years were measured in this project. The postural parameters of 800 symptom-free male (n = 397) and female (n = 407) volunteers aged 21-60 years (Ø♀: 39.7 ± 11.6, Ø â™‚: 40.7 ± 11.5 y) were studied. The mean height of the men was 1.8 ± 0.07 m, with a mean body weight of 84.8 ± 13.1 kg and an average BMI of 26.0 ± 3.534 kg/m2. In contrast, the mean height of the women was 1.67 ± 0.06 m, with a mean body weight of 66.5 ± 12.7 kg and an average BMI of 23.9 ± 4.6 kg/m2. By means of video rasterstereography, a 3-dimensional scan of the upper back surface was measured when in a habitual standing position. The means or medians, confidence intervals, tolerance ranges, the minimum, 2.5, 25, 50, 75, 97.5 percentiles and the maximum, plus the kurtosis and skewness of the distribution, were calculated for all parameters. Additionally, ANOVA and a factor analyses (sex, BMI, age) were conducted. In both sexes across all age groups, balanced, symmetrical upper body statics were evident. Most strikingly, the females showed greater thoracic kyphosis and lumbar lordosis angles (kyphosis: Ø â™€ 56°, Ø♂ 51°; lordosis: Ø â™€ 49°, Ø♂ 32°) and lumbar bending angles (Ø â™€ 14°, Ø♂ 11°) than the males. The distance between the scapulae was more pronounced in men. These parameters also show an increase with age and BMI, respectively. Pelvic parameters were independent of age and sex. The upper body postures of women and men between the ages of 21 and 60 years were found to be almost symmetrical and axis-conforming with a positive correlation for BMI or age. Consequently, the present body posture parameters allow for comparisons with other studies, as well as for the evaluation of clinical (interim) diagnostics and applications.


Assuntos
Cifose , Lordose , Humanos , Masculino , Adulto , Feminino , Adulto Jovem , Pessoa de Meia-Idade , Lordose/diagnóstico por imagem , Índice de Massa Corporal , Cifose/diagnóstico por imagem , Postura , Região Lombossacral , Peso Corporal
4.
J Occup Med Toxicol ; 16(1): 7, 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33639978

RESUMO

OBJECTIVES: Symmetrical dental occlusion blocking is used in dentistry as a quick diagnostic tool to test for potential influences of the craniomandibular system on body sway and weight distribution. This study presents the changes of body sway and pressure distribution in healthy subjects, free of a temporomandibular dysfunction (TMD). Immediate effects between occlusal blocking and rest position on body sway and body weight distribution in general, as well as for both genders and for four age decades will be evaluated. MATERIALS AND METHODS: 725 (396f/329 m) subjects (neither subjective signs of TMD nor acute/chronic complaints in the musculoskeletal system) volunteered (21 to 60 years) while both genders were divided into four age groups according to decades. A pressure measuring platform was used. Body sway and weight distribution were recorded in two dental occlusion conditions (a) in rest position and (b) symmetrical blocking (bicuspid region) by cotton rolls. RESULTS: Both, the frontal sway and the sagittal sway reduced by 0.67 mm (t(724) = - 3.9 (p <  0.001)) and by 0.33 mm (t(724) = - 3.4 (p <  0.001)). The relative pressure under the left forefoot increased by 0.33% (t(724) = 2.88 (p <  0.001)) and the relative pressure overall under the forefoot increased by 0.67% (t(724) = - 3.4 (p <  0.001)). Gender-specific, age-specific and BMI-specific reactions could not be identified. CONCLUSIONS: Subjects, free of any TMD and with no complaints of the musculoskeletal system, show small changes of the body sway and weight distribution when biting symmetrically on a cotton roll. These changes are independent of age, gender or body mass index (BMI). Due to the relative large sample size, the presented results can also be seen as norm values when body sway is used as an additional assessment of a TMD.

5.
Opt Express ; 16(24): 19770-8, 2008 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-19030062

RESUMO

The Kramers-Kronig relations between the real and imaginary parts of a response function are widely used in solid-state physics to evaluate the corresponding quantity if only one component is measured. They are among the most fundamental statements since only based on the analytical behavior and causal nature of the material response [Phys. Rev. 104, 1760-1770 (1956)]. Optical losses, for instance, can be obtained from the dispersion of the dielectric constant at all wavelengths, and vice versa [Handbook of optical constants of solids, Vol. 1, p. 35]. Although the general validity was never casted into doubt, it is a longstanding problem that Kramers-Kronig relations cannot simply be applied to anisotropic crystalline materials because contributions from different directions mix in a frequency-dependent way. Here we present a general method to identify frequency-independent principal polarizability directions for which the Kramers-Kronig relations are obeyed even in materials with lowest symmetry. Using generalized spectroscopic ellipsometry on a single crystal surface of triclinic pentacene, as an example, enables us to evaluate the complex dielectric constant and to compare it with band-structure calculations along the crystallographic directions. A general recipe is provided how to proceed from a macroscopic measurement on a low symmetry crystal plane to the microscopic dielectric properties of the unit cell, along whose axes the Kramers-Kronig relations hold.

6.
Eur Phys J E Soft Matter ; 27(4): 421-4, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19104858

RESUMO

X-ray diffraction, atomic force microscopy and spectroscopic ellipsometry were used to study tetracene thin films as a function of deposition rate. A comparative analysis of the thickness and roughness values allows for detailed modelling of the film morphology. An interdigitated growth mode is established for the coexisting thin film and bulk phases. By comparison with the respective quinone-derivative of tetracene, we were additionally able to identify reaction products by their optical response.

7.
Nat Commun ; 6: 7578, 2015 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-26151881

RESUMO

Vacancy-related centres in silicon carbide are attracting growing attention because of their appealing optical and spin properties. These atomic-scale defects can be created using electron or neutron irradiation; however, their precise engineering has not been demonstrated yet. Here, silicon vacancies are generated in a nuclear reactor and their density is controlled over eight orders of magnitude within an accuracy down to a single vacancy level. An isolated silicon vacancy serves as a near-infrared photostable single-photon emitter, operating even at room temperature. The vacancy spins can be manipulated using an optically detected magnetic resonance technique, and we determine the transition rates and absorption cross-section, describing the intensity-dependent photophysics of these emitters. The on-demand engineering of optically active spins in technologically friendly materials is a crucial step toward implementation of both maser amplifiers, requiring high-density spin ensembles, and qubits based on single spins.

8.
Int J Circumpolar Health ; 57 Suppl 1: 91-5, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10093253

RESUMO

This paper describes partnerships between service and education that can assist in meeting the health care needs of vulnerable population groups. Baccalaureate nursing students learn about population-based nursing practice as a means of addressing health needs. Each semester, groups of 8-10 senior students work with a community agency serving a population at risk. Students assess health needs and plan, implement, and evaluate a health promotion intervention with the population and the agency. Emphasis is placed on designing culturally appropriate interventions that are accomplished in partnership with the agency and population. Projects which illustrate the generalizability of this approach will be discussed. Such experiences reduce barriers that separate education from practice. Community agencies benefit as health needs that might not otherwise be met are addressed.


Assuntos
Etnicidade , Promoção da Saúde/métodos , Necessidades e Demandas de Serviços de Saúde/organização & administração , Relações Interprofissionais , Alaska , Educação em Enfermagem/organização & administração , Educação em Saúde/organização & administração , Promoção da Saúde/organização & administração , Humanos , Serviços Preventivos de Saúde/organização & administração
9.
Nat Chem ; 5(3): 187-94, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23422560

RESUMO

Large π-conjugated molecules, when in contact with a metal surface, usually retain a finite electronic gap and, in this sense, stay semiconducting. In some cases, however, the metallic character of the underlying substrate is seen to extend onto the first molecular layer. Here, we develop a chemical rationale for this intriguing phenomenon. In many reported instances, we find that the conjugation length of the organic semiconductors increases significantly through the bonding of specific substituents to the metal surface and through the concomitant rehybridization of the entire backbone structure. The molecules at the interface are thus converted into different chemical species with a strongly reduced electronic gap. This mechanism of surface-induced aromatic stabilization helps molecules to overcome competing phenomena that tend to keep the metal Fermi level between their frontier orbitals. Our findings aid in the design of stable precursors for metallic molecular monolayers, and thus enable new routes for the chemical engineering of metal surfaces.


Assuntos
Metais/química , Naftacenos/química , Quinonas/química , Modelos Moleculares , Semicondutores , Propriedades de Superfície , Termodinâmica
10.
Opt Lett ; 32(11): 1578-80, 2007 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-17546194

RESUMO

The optical properties of ultrathin Au films on silicon have been studied in the infrared over a wide frequency range from 200 to 10,000 cm(-1). Thick films show a Drude behavior; i.e., with increasing frequency the transmission increases; for films below the percolation threshold at about 5 nm a negative slope for the frequency-dependent transmission is observed. When the thickness is further reduced, between 1 and 3 nm an anomaly occurs: the relative transmission reaches maximum values above 100% compared with the bare substrate, indicating an antireflection coating of nanometer thickness for light of 5 microm wavelength. This anomaly can be explained in the framework of effective-medium theories.

11.
Phys Chem Chem Phys ; 8(15): 1834-6, 2006 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-16633669

RESUMO

We study the growth and structure of thin films of the organic semiconductor rubrene during organic molecular beam deposition (OMBD) on silicon oxide in situ and in real time using X-ray scattering. Using in situ grazing incidence diffraction (GID) we find a small degree of local order but an otherwise largely disordered structure, consistent with out of plane scans. Monitoring the surface morphology in real time during growth, we find relatively smooth films (surface roughness sigma below approximately 15 A for thicknesses up to at least 600 A) and a significant delay before the onset of roughening. This anomalous roughening in the beginning and crossover to normal roughening later during growth may be related to conformational changes of rubrene in the early stages of growth.


Assuntos
Naftacenos/química , Dióxido de Silício/química , Compostos Orgânicos/química , Semicondutores , Espectrometria por Raios X , Propriedades de Superfície , Fatores de Tempo
12.
Eur Phys J E Soft Matter ; 17(3): 339-43, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15968478

RESUMO

We use ultraviolet photoelectron spectroscopy to investigate the effect of oxygen and air exposure on the electronic structure of pentacene single crystals and thin films. It is found that O(2) and water do not react noticeably with pentacene, whereas singlet oxygen/ozone readily oxidize the organic compound. Also, we obtain no evidence for considerable p-type doping of pentacene by O(2) at low pressure. However, oxygen exposure lowers the hole injection barrier at the interface between Au and pentacene by 0.25 eV, presumably due to a modification of the Au surface properties.


Assuntos
Eletroquímica/métodos , Nanoestruturas/química , Compostos Orgânicos/química , Oxigênio/química , Semicondutores , Espectrofotometria Ultravioleta , Teste de Materiais/métodos , Nanoestruturas/análise , Compostos Orgânicos/análise
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