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1.
Z Gerontol Geriatr ; 52(2): 130-138, 2019 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-30847545

RESUMO

BACKGROUND: Although socioeconomic differences in the mortality of middle-aged persons is well-researched, little is known about socioeconomic inequalities in mortality in the very old population. Surveys and population census follow-up studies in this age group are associated with reliability and validity problems. OBJECTIVE: The aim of the study was to investigate, by linking statistical information from register data, to what extent differences in mortality exist among very old Austrian men by socioeconomic variables (e.g. education and income) and if these can be explained by differences in health status. MATERIAL AND METHODS: The data records on men aged 80-99 years counted in the Austrian register-based population census from 2011 were augmented by information from tax and social security data and merged with deaths in a 5-year follow-up period. Relative mortality risks were estimated by Cox regression. The health status was operationalized by the standardized level of care. RESULTS: Even in very old men significant differences in mortality exist depending on the socioeconomic status. A systematic effect was found for education and a poverty effect for income. When controlling not just for age but also for the standardized level of care, no socioeconomic disparities in mortality were observed. The higher mortality risk for less educated and low income very old men is thus a result of a poorer health status. CONCLUSION: At ages over 80 years the health status is the essential influencing factor on mortality. Measures to reduce socioeconomic disparities in mortality must therefore focus on earlier phases in life, in order to reduce the extent of care dependency among socially disadvantaged groups.


Assuntos
Disparidades nos Níveis de Saúde , Renda , Mortalidade , Classe Social , Idoso de 80 Anos ou mais , Áustria , Humanos , Masculino , Reprodutibilidade dos Testes , Fatores Socioeconômicos
2.
Sci Data ; 11(1): 751, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987534

RESUMO

The complex meso- and microclimatic heterogeneity inherent to mountainous regions, driven by both topographic and biotic factors, and the lack of observations, poses significant challenges to using climate models to predict and understand impacts at various scales. We present here a six-year dataset (2017-2022) of continuous climatic measurements collected at five elevations from 983 m to 2705 m above sea level in the Val Mazia - Matschertal valley in the Italian Alps. The measurements include the air temperature, relative humidity, wind speed and direction, solar radiation, soil properties, precipitation, and snow height. Collected within the European Long-Term Ecological Research program (LTER), this dataset is freely available in an open access repository. The time series may be valuable for the validation of regional climate models, atmospheric exchange modelling, and providing support for hydrological models and remote sensing products in mountain environments. Additionally, our data may be useful for research on the influence of elevation on ecological processes such as vegetation growth, plant composition, and soil biology. Beyond its utility in advancing such fundamental research, meteorological monitoring data contribute to informed socio-political decisions on climate adaptation strategies, land management, and water resource planning, enhancing the safety and resilience of mountain communities and biodiversity.

3.
BMC Bioinformatics ; 14 Suppl 10: S4, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24267277

RESUMO

In this paper we present an algorithm based on the sum-product algorithm that finds elements in the preimage of a feed-forward Boolean networks given an output of the network. Our probabilistic method runs in linear time with respect to the number of nodes in the network. We evaluate our algorithm for randomly constructed Boolean networks and a regulatory network of Escherichia coli and found that it gives a valid solution in most cases.


Assuntos
Algoritmos , Biologia Computacional , Redes Reguladoras de Genes , Biologia Computacional/métodos , Simulação por Computador , Escherichia coli/genética , Modelos Genéticos , Probabilidade
4.
Int Orthop ; 37(7): 1355-61, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23512602

RESUMO

PURPOSE: The purpose of this study was to evaluate the different temperature levels while drilling solid materials and to compare different cooling solutions for possible temperature control. An additional purpose was to develop an internal cooling device which can be connected to routinely used manual drilling devices in trauma surgery. METHODS: Drilling was performed on a straight hip stem implanted in bovine femora without cooling, with externally applied cooling and with a newly developed internal cooling device. Temperature changes were measured by seven thermocouples arranged near the borehole. Additionally, thermographic scans were performed during drilling. RESULTS: Drilling without cooling leads to an immediate increase in temperature to levels of thermal osteonecrosis (over 200 °C). With externally applied cooling temperatures were decreased, but were still up to a tissue damaging 85 °C. Internally applied cooling led to a temperature decrease to tissue-preserving levels during the drilling procedure (24.7 °C). CONCLUSION: Internal cooling with HPC-drillers lowered the measured temperatures to non-tissue damaging temperatures and should avoid structural tissue damage.


Assuntos
Teste de Materiais , Equipamentos Ortopédicos/normas , Ortopedia/métodos , Temperatura , Animais , Bovinos , Desenho de Equipamento , Articulação do Quadril/cirurgia , Prótese de Quadril , Modelos Animais
5.
Int Orthop ; 37(10): 1885-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23775453

RESUMO

PURPOSE: The purpose of this study was to evaluate the different temperature levels whilst drilling cemented and cementless hip prostheses implanted in bovine femora, and to evaluate the insulating function of the cement layer. METHODS: Standard hip prostheses were implanted in bovine donor diaphyses, with or without a cement layer. Drilling was then performed using high-performance-cutting drills with a reinforced core, a drilling diameter of 5.5 mm and cooling channels through the tip of the drill for constantly applied internal cooling solution. An open type cooling model was used in this setup. Temperature was continuously measured by seven thermocouples placed around the borehole. Thermographic scans were also performed during drilling. RESULTS: At the cemented implant surface, the temperature never surpassed 24.7 °C when constantly applied internal cooling was used. Without the insulating cement layer (i.e. during drilling of the cementless bone-prosthesis construct), the temperature increased to 47 °C. CONCLUSION: Constantly applied internal cooling can avoid structural bone and soft tissue damage during drilling procedures. With a cement layer, the temperatures only increased to non-damaging levels. The results could be useful in the treatment of periprosthetic fractures with intraprosthetic implant fixation.


Assuntos
Artroplastia de Quadril/métodos , Cimentos Ósseos , Fraturas do Fêmur/cirurgia , Prótese de Quadril , Fraturas Periprotéticas/cirurgia , Condutividade Térmica , Animais , Artroplastia de Quadril/instrumentação , Fenômenos Biomecânicos , Bovinos , Modelos Animais , Desenho de Prótese , Temperatura
7.
Nat Commun ; 10(1): 2475, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31171775

RESUMO

Weyl and Dirac fermions have created much attention in condensed matter physics and materials science. Recently, several additional distinct types of fermions have been predicted. Here, we report ultra-high electrical conductivity in MoP at low temperature, which has recently been established as a triple point fermion material. We show that the electrical resistivity is 6 nΩ cm at 2 K with a large mean free path of 11 microns. de Haas-van Alphen oscillations reveal spin splitting of the Fermi surfaces. In contrast to noble metals with similar conductivity and number of carriers, the magnetoresistance in MoP does not saturate up to 9 T at 2 K. Interestingly, the momentum relaxing time of the electrons is found to be more than 15 times larger than the quantum coherence time. This difference between the scattering scales shows that momentum conserving scattering dominates in MoP at low temperatures.

8.
Med Eng Phys ; 36(2): 239-43, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23993993

RESUMO

BACKGROUND: The purpose of this study was to develop a new fixation technique for the treatment of periprosthetic fractures using intraprosthetic screw fixation. The goal was to biomechanically evaluate the increase in primary fixation stability compared to unicortical locked-screw plating. METHODS: A Vancouver C periprosthetic fracture was simulated in femur prosthesis constructs. Fixation was then performed with either unicortical locked-screw plating using the LISS-plate or with intraprosthetic screw fixation. Fixation stability was compared in an axial load-to-failure model. RESULTS: The intraprosthetic fixation model was superior to the unicortical locked-screw fixation in all tested devices. The intraprosthetic fixation model required 11,807N±1596N for failure and the unicortical locked-screw plating required 7649N±653N (p=0.002). CONCLUSION: Intraprosthetic screw anchorage with a special prosthesis drill enhances the primary stability in treating periprosthetic fractures by internal fixation.


Assuntos
Parafusos Ósseos , Fraturas do Fêmur/cirurgia , Fixação Interna de Fraturas , Fenômenos Mecânicos , Fraturas Periprotéticas/cirurgia , Fenômenos Biomecânicos , Fraturas do Fêmur/etiologia , Prótese de Quadril/efeitos adversos , Teste de Materiais , Fraturas Periprotéticas/etiologia
9.
PLoS One ; 8(5): e64371, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23741321

RESUMO

Nested canalizing Boolean functions (NCF) play an important role in biologically motivated regulatory networks and in signal processing, in particular describing stack filters. It has been conjectured that NCFs have a stabilizing effect on the network dynamics. It is well known that the average sensitivity plays a central role for the stability of (random) Boolean networks. Here we provide a tight upper bound on the average sensitivity of NCFs as a function of the number of relevant input variables. As conjectured in literature this bound is smaller than 4/3. This shows that a large number of functions appearing in biological networks belong to a class that has low average sensitivity, which is even close to a tight lower bound.


Assuntos
Análise de Fourier , Redes Reguladoras de Genes , Modelos Estatísticos , Simulação por Computador
10.
EURASIP J Bioinform Syst Biol ; 2013(1): 1, 2013 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-23311536

RESUMO

: Transcriptional regulation networks are often modeled as Boolean networks. We discuss certain properties of Boolean functions (BFs), which are considered as important in such networks, namely, membership to the classes of unate or canalizing functions. Of further interest is the average sensitivity (AS) of functions. In this article, we discuss several algorithms to test the properties of interest. To test canalizing properties of functions, we apply spectral techniques, which can also be used to characterize the AS of functions as well as the influences of variables in unate BFs. Further, we provide and review upper and lower bounds on the AS of unate BFs based on the spectral representation. Finally, we apply these methods to a transcriptional regulation network of Escherichia coli, which controls central parts of the E. coli metabolism. We find that all functions are unate. Also the analysis of the AS of the network reveals an exceptional robustness against transient fluctuations of the binary variables.a.

11.
World J Orthop ; 3(10): 162-6, 2012 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-23326763

RESUMO

AIM: To develop new fixation techniques for the treatment of periprosthetic fractures using intraprosthetic screw fixation with inserted threaded liners. METHODS: A Vancouver B1 periprosthetic fracture was simulated in femur prosthesis constructs using sawbones and cemented regular straight hip stems. Fixation was then performed with either unicortical locked-screw plating using the less invasive stabilization system-plate or with intraprosthetic screw fixation using inserted liners. Two experimental groups were formed using either prostheses made of titanium alloy or prostheses made of cobalt chrome alloy. Fixation stability was compared in an axial load-to-failure model. Drilling was performed using a specially invented prosthesis drill with constantly applied internal cooling. RESULTS: The intraprosthetic fixation model with titanium prostheses was superior to the unicortical locked-screw fixation in all tested devices. The intraprosthetic fixation model required 10 456 N ± 1892 N for failure and the unicortical locked-screw plating required 7649 N ± 653 N (P < 0.05). There was no significant difference between the second experimental group and the control group. CONCLUSION: Intraprosthetic screw anchorage with special threaded liners enhances the primary stability in treating periprosthetic fractures by internal fixation.

12.
EURASIP J Bioinform Syst Biol ; 2012(1): 14, 2012 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-23033959

RESUMO

: Bacterial strains that were genetically blocked in important metabolic pathways and grown under selective conditions underwent a process of adaptive evolution: certain pathways may have been deregulated and therefore allowed for the circumvention of the given block. A block of endogenous pyruvate synthesis from glycerol was realized by a knockout of pyruvate kinase and phosphoenolpyruvate carboxylase in E. coli. The resulting mutant strain was able to grow on a medium containing glycerol and lactate, which served as an exogenous pyruvate source. Heterologous expression of a pyruvate carboxylase gene from Corynebacterium glutamicum was used for anaplerosis of the TCA cycle. Selective conditions were controlled in a continuous culture with limited lactate feed and an excess of glycerol feed. After 200-300 generations pyruvate-prototrophic mutants were isolated. The genomic analysis of an evolved strain revealed that the genotypic basis for the regained pyruvate-prototrophy was not obvious. A constraint-based model of the metabolism was employed to compute all possible detours around the given metabolic block by solving a hierarchy of linear programming problems. The regulatory network was expected to be responsible for the adaptation process. Hence, a Boolean model of the transcription factor network was connected to the metabolic model. Our model analysis only showed a marginal impact of transcriptional control on the biomass yield on substrate which is a key variable in the selection process. In our experiment, microarray analysis confirmed that transcriptional control probably played a minor role in the deregulation of the alternative pathways for the circumvention of the block.

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