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2.
Z Geburtshilfe Neonatol ; 220(2): 66-73, 2016 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-27111593

RESUMO

AIM: We aimed to develop national reference values for birth weight, length, head circumference, and weight for length for newborn triplets based on data from the German perinatal survey of 2007-2011. MATERIAL AND METHODS: Perinatal survey data of 3,690 newborn triplets from all the states of Germany were kindly provided to us by the AQUA Institute in Göttingen, Germany. Data of 3,567 newborn triplets were included in the analyses. Sex-specific percentile values were calculated using cumulative frequencies. Percentile values at birth were computed for the 3rd, 10th, 25th, 50th, 75th, 90th, and 97th percentiles for 21-36 completed weeks of gestation. RESULTS AND CONCLUSIONS: We present the first German reference values (tables and curves) for the anthropometric dimensions of triplet neonates and compare selected birth weight and length percentiles of triplets (after 32 and 34 completed weeks of gestation) to those of singletons and twins. The differences in the 50th birth weight percentiles between singletons and triplets after 32 completed weeks of gestation were 180 g for girls and 210 g for boys; after 34 weeks of gestation the differences were 320 and 325 g, respectively. The differences between twins and triplets after 32 weeks of gestation were 100 g for girls and 120 g for boys; after 34 weeks of gestation they were 130 and 135 g, respectively. The data presented here enable the classification of newborn triplets according to somatic parameters making reference to German perinatal data.


Assuntos
Antropometria/métodos , Peso ao Nascer , Estatura , Inquéritos Epidemiológicos , Valores de Referência , Trigêmeos/classificação , Trigêmeos/estatística & dados numéricos , Feminino , Alemanha/epidemiologia , Idade Gestacional , Humanos , Recém-Nascido , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição por Sexo
3.
Artigo em Inglês | MEDLINE | ID: mdl-26391194

RESUMO

The capabilities of modern semiconductor manufacturing offer remarkable possibilities to be applied in life science research as well as for its commercialization. In this review, the technology modules available in micro- and nano-electronics are exemplarily presented for the case of 250 and 130 nm technology nodes. Preparation procedures and the different transistor types as available in complementary metal-oxide-silicon devices (CMOS) and BipolarCMOS (BiCMOS) technologies are introduced as key elements of comprehensive chip architectures. Techniques for circuit design and the elements of completely integrated bioelectronics systems are outlined. The possibility for life scientists to make use of these technology modules for their research and development projects via so-called multi-project wafer services is emphasized. Various examples from diverse fields such as (1) immobilization of biomolecules and cells on semiconductor surfaces, (2) biosensors operating by different principles such as affinity viscosimetry, impedance spectroscopy, and dielectrophoresis, (3) complete systems for human body implants and monitors for bioreactors, and (4) the combination of microelectronics with microfluidics either by chip-in-polymer integration as well as Si-based microfluidics are demonstrated from joint developments with partners from biotechnology and medicine. WIREs Nanomed Nanobiotechnol 2016, 8:355-377. doi: 10.1002/wnan.1367 For further resources related to this article, please visit the WIREs website.


Assuntos
Biotecnologia , Eletrônica Médica , Nanotecnologia , Biotecnologia/instrumentação , Biotecnologia/métodos , Eletrônica Médica/instrumentação , Eletrônica Médica/métodos , Desenho de Equipamento , Nanotecnologia/instrumentação , Nanotecnologia/métodos , Semicondutores
4.
Radiologe ; 55(8): 654-62, 2015 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-26245985

RESUMO

Flat detectors (FD) have completely replaced image intensifiers in angiography. Due to this development not only the image quality of 2D digital subtraction angiography series (2-D-DSA) could be improved but also the acquisition of computed tomography (CT)-like cross-sectional images (FD-CT) within the angio suite became feasible. These techniques are now being used in daily clinical routine. Only little information about effective doses of these applications to patients has been published in the literature. We describe the effective patient dose of current applications in the field of angiography and demonstrate strategies to minimize the dose to the patient. In addition, we compare FD-CT applications to standard multislice CT applications.


Assuntos
Angiografia Cerebral/instrumentação , Neurorradiografia/instrumentação , Segurança do Paciente , Proteção Radiológica/instrumentação , Tomografia Computadorizada por Raios X/instrumentação , Ecrans Intensificadores para Raios X , Angiografia Cerebral/métodos , Desenho de Equipamento , Segurança de Equipamentos , Humanos , Neurorradiografia/métodos , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos
5.
Vet Comp Orthop Traumatol ; 28(5): 295-300, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26195005

RESUMO

OBJECTIVES: To compare the results of femoral head and neck excision (FHNE) ostectomy performed by two novice veterinarians using an osteotome and mallet or microsagittal saw. METHODS: In this ex vivo cadaveric study, hindlimbs of eight canine cadavers were randomized to FHNE with osteotome or micro sagittal saw as performed by two recently graduated veterinarians. The hindimbs were imaged by computed tomography (CT) before and after the osteotomy. Post FHNE CT images were evaluated by a board certified radiologist blinded to the ostectomy technique for assessment of the number of bone fragments, fissures, smoothness of osteotomy margination, and volume of residual femoral neck. RESULTS: Femoral head and neck excision performed with the osteotome produced more peri-ostectomy bone fragments, cortical fissures, irregular margins, and residual femoral neck volume, compared with osteotomy using a saw. CLINICAL RELEVANCE: Compared to FHNE performed with a sagittal saw, osteotome FHNE resulted in a greater bone trauma and residual neck bone volume, which would require post-ostectomy modification in a clinical setting.


Assuntos
Cães/cirurgia , Cabeça do Fêmur/cirurgia , Colo do Fêmur/cirurgia , Osteotomia/veterinária , Animais , Cabeça do Fêmur/diagnóstico por imagem , Colo do Fêmur/diagnóstico por imagem , Osteotomia/instrumentação , Osteotomia/métodos , Terapia de Salvação/veterinária , Instrumentos Cirúrgicos/veterinária , Tomografia Computadorizada por Raios X/veterinária
6.
J Chem Phys ; 142(22): 224703, 2015 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-26071723

RESUMO

We investigate the vibrational properties of perfluororubrene (PF-RUB) in thin films on silicon wafers with a native oxide layer as well as on silicon wafers covered with a self-assembled monolayer and in dichloromethane solution. In comparison with computed Raman and IR spectra, we can assign the molecular modes and identify two molecular conformations with twisted and planar tetracene backbones of the molecule. Moreover, we employ Raman imaging techniques to study the morphology and distribution of the molecular conformation in PF-RUB thin films.

7.
J Chem Phys ; 143(24): 244905, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26723709

RESUMO

In current organic photovoltaic devices, the loss in energy caused by the charge transfer step necessary for exciton dissociation leads to a low open circuit voltage, being one of the main reasons for rather low power conversion efficiencies. A possible approach to avoid these losses is to tune the exciton binding energy to a value of the order of thermal energy, which would lead to free charges upon absorption of a photon, and therefore increase the power conversion efficiency towards the Shockley-Queisser limit. We determine the size of the excitons for different organic molecules and polymers by time dependent density functional theory calculations. For optically relevant transitions, the exciton size saturates around 0.7 nm for one-dimensional molecules with a size longer than about 4 nm. For the ladder-type polymer poly(benzimidazobenzophenanthroline), we obtain an exciton binding energy of about 0.3 eV, serving as a lower limit of the exciton binding energy for the organic materials investigated. Furthermore, we show that charge transfer transitions increase the exciton size and thus identify possible routes towards a further decrease of the exciton binding energy.

8.
Z Geburtshilfe Neonatol ; 218(6): 254-60, 2014 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-25518831

RESUMO

AIM: The aim of this study was to develop new national standards for birth weight, length, head circumference, and weight for length for newborn twins based on the German perinatal survey of 2007-2011. We also assessed trends in anthropometric measurements by comparing these new percentile values with the percentile values of 1990-1994. MATERIAL AND METHODS: Perinatal survey data of 110,313 newborn twins from all the states of Germany collected in the years 2007-2011 were kindly provided by the AQUA Institute in Göttingen, Germany. Sex specific percentile values were calculated using cumulative frequencies. Percentile values at birth were computed for the 3rd, 10th, 25th, 50th, 75th, 90th, and 97th percentiles for 21-40 completed weeks of gestation. Percentile curves and tabulated values for the years 2007-2011 were compared with the published values of 1990-1994. RESULTS AND DISCUSSION: The new percentile curves (2007-2011) closely resemble the previous ones (1990-1994). Small differences can nonetheless be found. For example, for birth weight the new values for the 10th percentile are a little higher. CONCLUSIONS: We recommend using the new percentile values instead of the old ones.


Assuntos
Antropometria , Tamanho Corporal/fisiologia , Pesquisas sobre Atenção à Saúde , Recém-Nascido/fisiologia , Gêmeos/estatística & dados numéricos , Peso ao Nascer/fisiologia , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição por Sexo
9.
Z Geburtshilfe Neonatol ; 218(5): 210-7, 2014 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-25353215

RESUMO

AIM: The aim of this study was to derive percentile values for birth weight, length, head circumference, and weight for length for singleton neonates based on the German perinatal survey of 2007-2011 (using data from all 16 states of Germany). We also compared these new percentile values with the percentile values of 1995-2000 that so far have been considered standard values. MATERIAL AND METHODS: Data of 3 187 920 singleton neonates from the German perinatal survey of the years 2007-2011 were kindly provided to us by the AQUA Institute in Göttingen, Germany. Sex specific percentile values were calculated using cumulative frequencies. Percentile values at birth were computed for the 3(rd), 10(th), 25(th), 50(th), 75(th), 90(th), and 97(th) percentiles for 21-43 completed weeks of gestation. Percentile curves and tabulated values for the years 2007-2011 were compared with the published values of 1995-2000. RESULTS AND DISCUSSION: Overall the new percentile curves closely resemble the previous ones. Minimal differences can be found for the 10(th) percentile and generally for early weeks of gestation. Values for the 10(th) percentile in the 2007-2011 dataset are somewhat higher than values of 1995-2000 for birth weight, length, and weight for length. CONCLUSIONS: We recommend the use of these new percentile values instead of the old ones.


Assuntos
Antropometria/métodos , Tamanho Corporal/fisiologia , Recém-Nascido/fisiologia , Resultado da Gravidez/epidemiologia , Coleta de Dados , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Gravidez , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição por Sexo , Fatores Sexuais
10.
Z Rheumatol ; 73(1): 77-84, 2014 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-24310229

RESUMO

BACKGROUND: The perioperative administration of antirheumatic medication can lead to an increased risk of infection and to a malfunction in wound healing up to a manifest infection; however, the termination of antirheumatic therapy can result in a flare up of the disease. Both situations can endanger the success of the operation, particularly in arthroplasty. METHOD: The recommendations have been developed and approved by the Pharmacotherapy Commission of the German Society for Rheumatology following a systematic literature search (as of 30 April 2013) and a consensus process. RESULTS: As very little data with sufficiently high evidence are available, the present recommendations should be considered as having an advisory quality and an individual risk assessment should always be carried out. Classical disease-modifying antirheumatic drugs (DMARD), such as methotrexate can be continued in normal cases but whether this is also true for leflunomide is still undecided. For biologicals a break of two half-life periods before the operation is recommended. The therapy can be continued after wound healing has been completed and when there are no signs of infection.


Assuntos
Antirreumáticos/efeitos adversos , Antirreumáticos/uso terapêutico , Assistência Perioperatória/normas , Guias de Prática Clínica como Assunto , Doenças Reumáticas/terapia , Reumatologia/normas , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/prevenção & controle , Humanos , Doenças Reumáticas/complicações
11.
Opt Express ; 21(14): 16319-30, 2013 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-23938484

RESUMO

Bragg scattering effects in bottom-emitting organic light-emitting diodes (OLEDs) grown on corrugated aluminum-doped zinc oxide electrodes are analyzed. Periodic corrugation is introduced by structuring the oxide electrode via UV laser ablation, a process that enables flexible adjustment of the period and height of corrugation. We demonstrate that fabrication of stable and electrically efficient OLEDs on these rough substrates is feasible. Sharp spectral features are superimposed onto the broad emission spectra of the OLEDs, providing clear evidence for Bragg scattering of light from guided modes into the air cone. Theoretical analysis based on an emissive dipole model and conservation of momentum considerations allows a quantitative description of scattering and the associated dispersion relations.


Assuntos
Iluminação/instrumentação , Modelos Teóricos , Compostos Orgânicos/química , Refratometria/instrumentação , Semicondutores , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação , Propriedades de Superfície
12.
Phys Rev Lett ; 110(12): 126601, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-25166829

RESUMO

We demonstrate electric bistability induced by the positive feedback of self-heating onto the thermally activated conductivity in a two-terminal device based on the organic semiconductor C(60). The central undoped layer with a thickness of 300 nm is embedded between thinner n-doped layers adjacent to the contacts, minimizing injection barriers. The observed current-voltage characteristics follow the general theory for thermistors described by an Arrhenius-like conductivity law. Our findings include hysteresis phenomena and are of general relevance for the entire material class since most organic semiconductors can be described by a thermally activated conductivity.

13.
Geburtshilfe Frauenheilkd ; 73(12): 1247-1251, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24771906

RESUMO

Background and Aim: We have previously presented analyses of data obtained from the German Perinatal Survey for the years 1995-1997. Here we present an analysis of data from the years 2007-2011 and compare the data to the previous data from the 1990s. Material and Methods: For the years 1995-1997, the data on 1 815 318 singleton pregnancies were provided by the Chambers of Physicians of all the states of Germany except Baden-Württemberg. For the years 2007-2011, the data on 3 187 920 singleton pregnancies from the German Perinatal Survey (all states of Germany) were obtained from the AQUA Institute in Göttingen, Germany. SPSS was used for data analysis. Plausibility checks were performed on the data. Results: Mean maternal age has increased over the years, from 28.7 years in 1995 to 30.2 years in 2011. We observed a decrease in smoking. While not all cases included data on maternal smoking after the pregnancy was known, when the cases with data on smoking were analysed, in 1995-1997 23.5 % of pregnant women were smokers compared to 11.2 % smokers in 2007-2011. Maternal body mass index (BMI) also changed; 8.2 % of women were obese (BMI: 30-40 kg/m2), while 13.0 % were obese in 2011. In 1995, 0.6 % of women were morbidly obese (BMI ≥ 40 kg/m2) compared to 1.8 % of women in 2011. The mean maternal body weight at the time of the first obstetric consultation also increased from 65.9 kg in 1995 to 68.7 kg in 2011. Conclusions: While the decrease in the number of women smoking over time is clearly a positive development, increasing maternal age and obesity present challenges in clinical practice.

14.
Z Geburtshilfe Neonatol ; 217(6): 211-4, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24399320

RESUMO

BACKGROUND AND AIM: We have previously analysed neonatal characteristics and duration of pregnancy in Germany based on data from the German Perinatal Survey of 1995-1997. Here we describe neonatal characteristics and duration of pregnancy based on the German Perinatal Survey of 2007-2011. MATERIAL AND METHODS: We had been provided with data from the German Perinatal Survey of 1995-1997 by the chambers of physicians of all the states of Germany except Baden-Württemberg (1 815 318 singleton neonates). We were also provided with access to the perinatal survey data of 2007-2011 by the AQUA Institute in Göttingen, Germany (3 187 920 singleton neonates). We investigated regional differences within Germany and also compared the 2 periods of time. We used the computer programme SPSS for data analysis and performed plausibility checks on the survey data. RESULTS: Comparing the states of Germany, we found that birth weight was largest for neonates born in Schleswig-Holstein (3 407 g) and Mecklenburg-Western Pomerania (3 392 g); the lowest mean birth weight was observed in the Saarland (3 283 g). Preterm birth rate varied between 6.3% (Saxony) and 8.1% (Bremen, Saarland). Comparing 1995-1997 vs. 2007-2011, deliveries after 37 and 38 weeks of gestation were more common and deliveries after 39 and more weeks of gestation were less common in the later period of time. CONCLUSIONS: Regional differences in the anthropometric characteristics of neonates exist between the states of Germany. The proportion of deliveries after 39 and more weeks of gestation has decreased.


Assuntos
Pesquisas sobre Atenção à Saúde/tendências , Resultado da Gravidez/epidemiologia , Adolescente , Adulto , Peso ao Nascer , Feminino , Alemanha/epidemiologia , Idade Gestacional , Pesquisas sobre Atenção à Saúde/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Vigilância da População , Gravidez , Adulto Jovem
15.
J Chem Phys ; 136(5): 054701, 2012 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-22320753

RESUMO

We report detailed temperature dependent photoluminescence (PL) spectra of pentacene (PEN), perfluoropentacene (PFP), and PEN:PFP mixed thin films grown on SiO(2). PEN and PFP are particularly suitable for this study, since they are structurally compatible for good intermixing and form a model donor/acceptor system. The PL spectra of PEN are discussed in the context of existing literature and compared to the new findings for PFP. We analyze the optical transitions observed in the spectra of PEN and PFP using time-dependent density functional theory calculations. Importantly, for the mixed PEN:PFP film we observe an optical transition in PL at 1.4 eV providing evidence for coupling effects in the blend. We discuss a possible charge-transfer (CT) and provide a tentative scheme of the optical transitions in the blended films.

16.
Epidemiol Infect ; 140(4): 744-52, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21733249

RESUMO

The analysis of contact networks plays a major role to understanding the dynamics of disease spread. Empirical contact data is often collected using contact diaries. Such studies rely on self-reported perceptions of contacts, and arrangements for validation are usually not made. Our study was based on a complete network study design that allowed for the analysis of reporting accuracy in contact diary studies. We collected contact data of the employees of three research groups over a period of 1 work week. We found that more than one third of all reported contacts were only reported by one out of the two involved contact partners. Non-reporting is most frequent in cases of short, non-intense contact. We estimated that the probability of forgetting a contact of ≤5 min duration is greater than 50%. Furthermore, the number of forgotten contacts appears to be proportional to the total number of contacts.


Assuntos
Viés , Busca de Comunicante/métodos , Apoio Social , Humanos , Prontuários Médicos , Comportamento Social
17.
Environ Pollut ; 159(12): 3439-45, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21890252

RESUMO

Probabilistic material flow analysis and graph theory were combined to calculate predicted environmental concentrations (PECs) of engineered nanomaterials (ENMs) in Swiss rivers: 543 river sections were used to assess the geographical variability of nano-TiO(2), nano-ZnO and nano-Ag, and flow measurements over a 20-year period at 21 locations served to evaluate temporal variation. A conservative scenario assuming no ENM removal and an optimistic scenario covering complete ENM transformation/deposition were considered. ENM concentrations varied by a factor 5 due to uncertain ENM emissions (15%-85% quantiles of ENM emissions) and up to a factor of 10 due to temporal river flow variations (15%-85% quantiles of flow). The results indicate highly variable local PECs and a location- and time-dependent risk evaluation. Nano-TiO(2) median PECs ranged from 11 to 1'623 ng L(-1) (conservative scenario) and from 2 to 1'618 ng L(-1) (optimistic scenario). The equivalent values for nano-ZnO and nano-Ag were by factors of 14 and 240 smaller.


Assuntos
Monitoramento Ambiental , Nanoestruturas/análise , Rios/química , Poluentes Químicos da Água/análise , Engenharia , Modelos Teóricos , Suíça
18.
J Biomech ; 44(8): 1610-3, 2011 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-21481398

RESUMO

To provide a close-to-reality simulation model, such as for improved surgery planning, this model has to be experimentally verified. The present article describes the use of a 3D laser vibrometer for determining modal parameters of human pelvic bones that can be used for verifying a finite elements model. Compared to previously used sensors, such as acceleration sensors or strain gauges, the laser vibrometric procedure used here is a non-contact and non-interacting measuring method that allows a high density of measuring points and measurement in a global coordinate system. Relevant modal parameters were extracted from the measured data and provided for verifying the model. The use of the 3D laser vibrometer allowed the establishment of a process chain for experimental examination of the pelvic bones that was optimized with respect to time and effort involved. The transfer functions determined feature good signal quality. Furthermore, a comparison of the results obtained from pairs of pelvic bones showed that repeatable measurements can be obtained with the method used.


Assuntos
Lasers , Ossos Pélvicos/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Simulação por Computador , Feminino , Análise de Elementos Finitos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Anatômicos , Ossos Pélvicos/fisiologia , Pelve/patologia , Software , Vibração
19.
J Chem Phys ; 134(1): 014504, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21219004

RESUMO

Resonant and preresonant Raman spectra obtained on diindenoperylene (DIP) thin films are interpreted with calculations of the deformation of a relaxed excited molecule with density functional theory (DFT). The comparison of excited state geometries based on time-dependent DFT or on a constrained DFT scheme with observed absorption spectra of dissolved DIP reveals that the deformation pattern deduced from constrained DFT is more reliable. Most observed Raman peaks can be assigned to calculated A(g)-symmetric breathing modes of DIP or their combinations. As the position of one of the laser lines used falls into a highly structured absorption band, we have carefully analyzed the Raman excitation profile arising from the frequency dependence of the dielectric tensor. This procedure gives Raman cross sections in good agreement with the observed relative intensities, both in the fully resonant and in the preresonant case.


Assuntos
Indenos/química , Membranas Artificiais , Perileno/análogos & derivados , Perileno/química , Teoria Quântica , Análise Espectral Raman
20.
Phys Rev Lett ; 104(25): 257401, 2010 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-20867413

RESUMO

We present real-time in situ studies of optical spectra during thin film growth of several prototype organic semiconductors (pentacene, perfluoropentacene, and diindenoperylene) on SiO2. These data provide insight into surface and interface effects that are of fundamental importance and of relevance for applications in organic electronics. With respect to the bulk, the different molecular environment and structural changes within the first few monolayers can give rise to significant optical changes. Similar to interface-driven phenomena in, e.g., magnetism, spectral changes as a function of thickness d are a very general effect, decaying as 1/d in the simplest approximation. We observe energy shifts of 50-100 meV, rather small changes of the exciton-phonon coupling, and new transitions in specific systems, which should be considered as general features of the growth of organics.

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