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Recognising and responding appropriately to emotions is critical to adaptive psychological functioning. Psychopathic traits (e.g. callous, manipulative, impulsive, antisocial) are related to differences in recognition and response when emotion is conveyed through facial expressions and language. Use of emotional music stimuli represents a promising approach to improve our understanding of the specific emotion processing difficulties underlying psychopathic traits because it decouples recognition of emotion from cues directly conveyed by other people (e.g. facial signals). In Experiment 1, participants listened to clips of emotional music and identified the emotional content (Sample 1, N = 196) or reported on their feelings elicited by the music (Sample 2, N = 197). Participants accurately recognised (t(195) = 32.78, p < .001, d = 4.69) and reported feelings consistent with (t(196) = 7.84, p < .001, d = 1.12) the emotion conveyed in the music. However, psychopathic traits were associated with reduced emotion recognition accuracy (F(1, 191) = 19.39, p < .001) and reduced likelihood of feeling the emotion (F(1, 193) = 35.45, p < .001), particularly for fearful music. In Experiment 2, we replicated findings for broad difficulties with emotion recognition (Sample 3, N = 179) and emotional resonance (Sample 4, N = 199) associated with psychopathic traits. Results offer new insight into emotion recognition and response difficulties that are associated with psychopathic traits.
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Música , Humanos , Transtorno da Personalidade Antissocial/psicologia , Emoções/fisiologia , Medo , Expressão FacialRESUMO
Enamel demineralisation can develop on smooth surfaces as an undesirable side effect during orthodontic treatment with fixed appliances. This study aimed to evaluate the ability of 38% silver diamine fluoride in remineralisation (as estimated by fluorescence gain) of artificial initial lesions in smooth surfaces of human enamel. The smooth surfaces of 50 human tooth samples were artificially demineralised and 45 samples were allocated randomly into three groups receiving a single treatment with a varnish: group I: Riva Star (silver diamine fluoride, SDF), group II: Bifluorid 12 (NaF, CaF2), and group III: Cervitec F (CHX, CPC, NH4F). Five samples were assigned as a negative control group without treatment. All samples were exposed to pH-cycling for 28 days. Fluorescence behavior was measured using Quantitative light-induced fluorescence before and after demineralisation and up to four weeks on a weekly basis. Analysis of variance (ANOVA) with Tukey-Kramer post-hoc tests and repeated measures ANOVA were used for statistical evaluation (α = 0.05). After demineralisation, all samples showed mean ΔF of - 16.22% ± 4.35, without significance differences between the fluorescence behaviour of the samples (p = 0.251). After 28 days group comparison showed a statistically significant difference (p = 0.034) for ΔF values: the lowest fluorescence values were found in group I (SDF, mean ΔF - 16.47 ± 6.08) with a significant difference compared to group III (Cervitec F, mean ΔF - 11.71 ± 4.83). In group II (Bifluorid 12) mean ΔF value was - 15.55 ± 2.15) without statistically significant differences to groups I and III. The fluorescence behaviour of SDF varnish on smooth surfaces with artificial initial enamel lesions was significantly lower compared to Cervitec F varnish after short time use.
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Cárie Dentária , Fluorescência Quantitativa Induzida por Luz , Cárie Dentária/tratamento farmacológico , Esmalte Dentário , Fluoretos Tópicos/farmacologia , Fluoretos Tópicos/uso terapêutico , Humanos , Compostos de Amônio Quaternário , Compostos de Prata , Fluoreto de Sódio/uso terapêutico , Remineralização DentáriaRESUMO
BACKGROUND AND OBJECTIVE: Every year in Germany over 100,000 people, mostly of older age, suffer a proximal femoral fracture. Increasing case numbers in connection with an aging population and a relatively large number of concomitant diseases requiring treatment make everyday care more difficult. It is therefore of great importance to observe the quality of care for these patients using relevant quality parameters in order to be able to derive implications for everyday treatment practice. MATERIAL AND METHODS: The data of the external inpatient quality assurance from North Rhine-Westphalia for the years 2007-2008 and 2017-2018 were analyzed and the time periods compared. In addition, based on the documented secondary diagnosis and other influencing parameters, a risk adjustment was carried out with the aid of a logistic regression model with respect to the outcomes of general and surgical complications and mortality. Both osteosynthetically and endoprosthetically treated patients were taken into account. A total of 61,249 cases were included in the study. RESULTS: Positive developments could be observed in the area of surgical complications and wound infections with decreases of 1.2% and 0.8%, respectively. Patients with cardiovascular diseases had a particularly poor outcome. Here, improvements in the subcategory of cardiovascular events were found for general complications. The mortality remained unchanged at 6%. Operative activity on the weekends increased significantly. Patients whose hospital admission was related to the weekend did not show an increased risk of complications or mortality. Although the proportion of patients who were operated on after more than 48â¯h was reduced from 11.4% to 8.2%, the operation (>â¯24â¯h) was still delayed in 26.8% of cases. CONCLUSION: Against the background of increasing performance demands on the healthcare system, the results document improvements in some central areas of inpatient treatment. Nevertheless, the development of strategies for the further reduction of the preoperative waiting times in a medically justifiable manner is required. Internal concomitant diseases have a decisive influence on patient outcome. Thus, an adequate treatment of the multimorbid patient collective is to be established in everyday practice on the basis of close cooperation between geriatric traumatology and geriatric internal medicine departments.
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Fraturas do Fêmur , Fraturas do Colo Femoral , Idoso , Fraturas do Colo Femoral/epidemiologia , Fixação Interna de Fraturas/métodos , Humanos , Pacientes Internados , Risco AjustadoRESUMO
Vertebral osteomyelitis (VO) is an infection of the spine mainly caused by bacterial pathogens. The pathogenesis leading to destruction of intervertebral discs (IVDs) and adjacent vertebral bodies (VBs) is poorly described. The present study aimed at investigating the connection between infection and bone/disc metabolism in VO patients. 14 patients with VO (infection group) and 14 patients with burst fractures of the spine (fracture group; control) were included prospectively. Tissue biopsies from affected IVDs and adjacent VBs were analysed by RT-qPCR for mRNA-expression levels of 18 target genes including chemokines, adipokines and genes involved in bone metabolism. Most importantly, the receptor activator of NF-κB/osteoprotegerin (RANK/OPG) expression ratio was drastically elevated in both VBs and IVDs of the infection group. In parallel, expression of genes of the prostaglandin-E2-dependent prostanoid system was induced. Such genes regulate tissue degradation processes via the triad OPG/RANK/RANKL as well as via the chemokines IL-8 and CCL-20, whose expression was also found to be increased upon infection. The gene expression of the adipokine leptin, which promotes inflammatory tissue degradation, was higher in IVD tissue of the infection group, whereas the transcription of omentin and resistin genes, whose functions are largely unknown in the context of infectious diseases, was lower in infected VBs. In summary, similar expression patterns of pro-inflammatory cytokines and pro-osteoclastogenic factors were identified in VBs and IVDs of patients suffering from VO. This suggests that common immuno-metabolic pathways are involved in the mechanisms leading to tissue degradation in VBs and IVDs during VO.
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Disco Intervertebral , Osteomielite , Humanos , Osteoprotegerina , Ligante RANK , Receptor Ativador de Fator Nuclear kappa-B/genética , Corpo VertebralRESUMO
Future development of the modern nanoelectronics and its flagships internet of things, artificial intelligence, and neuromorphic computing is largely associated with memristive elements, offering a spectrum of inevitable functionalities, atomic level scalability, and low-power operation. However, their development is limited by significant variability and still phenomenologically orientated materials' design strategy. Here, we highlight the vital importance of materials' purity, demonstrating that even parts-per-million foreign elements substantially change performance. Appropriate choice of chemistry and amount of doping element selectively enhances the desired functionality. Dopant/impurity-dependent structure and charge/potential distribution in the space-charge layers and cell capacitance determine the device kinetics and functions. The relation between chemical composition/purity and switching/neuromorphic performance is experimentally evidenced, providing directions for a rational design of future memristive devices.
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The elementary steps of photocleavage in (coumarin-4-yl)methyl photoremovable protecting groups (PPGs) are elucidated by a combined electronic structure and time-resolved visible pump infrared probe (VIS-pump IR-probe) spectroscopic study. We specifically focus on the [7-(diethylamino)coumarin-4-yl]methyl (DEACM) PPG which has found increasing interest in biological applications over recent years. A series of leaving groups (LGs) are investigated, including azide (DEACM-N3), thiocyanate (DEACM-SCN), carbonate (DEACM-Carb), and a thymine nucleobase (DEACM-T) representing a model system for caged DNA. These systems are found to exhibit vastly different photocleavage time scales, ranging from the subpicosecond scale in the case of DEACM-SCN to â¼35 picoseconds in the case of DEACM-N3 and â¼540 picoseconds in the case of DEACM-Carb. In the case of DEACM-SCN, the appearance of the product is biphasic, with a fast (
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This paper presents a method for high-speed sample detection and position control in an electrostatic levitator. The algorithm uses images acquired from two charge coupled device cameras and allows for robust and reliable detection of the sample position under various process conditions. The results show improvements over position sensitive detector systems especially under harsh environments and during autonomous operation under microgravity conditions. The position of samples with a radius from 0.6 mm to 1.1 mm is detected in three dimensions with an accuracy of ±40 µm inside a 7 mm × 7 mm × 7 mm levitation area. The two orthogonally arranged cameras, recording images at a resolution of 260 px × 260 px, are used to calculate the position every 5 ms. The control model and the corresponding position controller for the three axes are presented as well. The system was successfully tested in the laboratory and under microgravity conditions at the drop tower, during parabolic flights, and on the MAPHEUS sounding rocket.
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BACKGROUND: Prostate-specific membrane antigen (PSMA) SPECT imaging in prostate cancer (PCa) could be a valuable alternative in regions where access to PSMA-PET imaging is restricted. [99mTc]Tc-PSMA-I&S is a new 99mTc-labeled PSMA-targeting SPECT agent, initially developed for radio-guided surgery. We report on the diagnostic use of [99mTc]Tc-PSMA-I&S-SPECT/CT in PCa. RESULTS: [99mTc]Tc-PSMA-I&S-SPECT/CT was performed and evaluated in 210 outpatients with PCa at a single center. Patients were imaged for biochemical recurrence (BCR, n = 152, mean PSA 8.7 ng/ml), for primary staging of high-risk PCa (n = 12, mean PSA 393 ng/ml), and restaging in advanced recurrent PCa (n = 46, mean PSA 101.3 ng/ml). Number and location of positive lesions were determined for the different subgroups. For BCR, detection rates were calculated, defined as the proportion of scans with at least one PSMA-positive lesion. PSMA positive lesions were detected in 65.2% of all 210 patients. Tumor tissue was mainly detected in lymph nodes (59%), in the bone (42%), and in the prostate (fossa) (28%). In the subgroup of patients referred for detection of BCR the detection rate increased from 20% at a PSA level < 1 ng/ml to 82.9% and 100% at PSA levels > 4 ng/ml and > 10 ng/ml, respectively. In the subgroup of high-risk patients referred for primary staging, 42% demonstrated metastatic disease. Restaging of advanced recurrent PCa revealed detectability of PSMA positive tumor lesions in 85% of the scans. CONCLUSIONS: [99mTc]Tc-PSMA-I&S-SPECT/CT was useful in PSMA-targeted imaging of PCa at various clinical stages. At low PSA levels (< 4 ng/ml), detection rates of [99mTc]Tc-PSMA-I&S-SPECT/CT in BCR are clearly inferior to data reported for PET-imaging and should thus only be considered for lesion detection if imaging with PET is unavailable. However, at higher PSA levels (> 4 ng/ml) [99mTc]Tc-PSMA-I&S-SPECT/CT provides high detection rates in BCR. [99mTc]Tc-PSMA-I&S-SPECT/CT can also be used for primary staging and for restaging of advanced recurrent PCa. However, further studies are needed to assess the clinical value in these indications.
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Marine mammals and diving birds face several physiological challenges under water, affecting their thermoregulation and locomotion as well as their sensory systems. Therefore, marine mammals have modified ears for improved underwater hearing. Underwater hearing in birds has been studied in a few species, but for the record-holding divers, such as penguins, there are no detailed data. We played underwater noise bursts to gentoo penguins (Pygoscelis papua) in a large tank at received sound pressure levels between 100 and 120 dB re 1 µPa RMS. The penguins showed a graded reaction to the noise bursts, ranging from no reactions at 100 dB to strong reactions in more than 60% of the playbacks at 120 dB re 1 µPa. The responses were always directed away from the sound source. The fact that penguins can detect and react to underwater stimuli may indicate that they make use of sound stimuli for orientation and prey detection during dives. Further, it suggests that penguins may be sensitive to anthropogenic noise, like many species of marine mammals.
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While most evidence types considered by forensic scientists result from the interactions between criminals, objects or victims at crime scenes, dust evidence arises from the mere presence of individuals and objects at locations of interest. Dust is ubiquitous. Yet, the use of dust evidence is anecdotical and is limited to cases where rare and characteristic particles are observed. The dust at any given location contains a large number of particles from different types and the dust present on an object or individual traveling across locations may be indicative of the locations recently visited by an individual, and, in particular, of the presence of an individual at a particular site of interest, e.g., the scene of a crime. In this paper, we propose to represent dust mixtures as vectors of counts of the individual particles, which can be characterised by any appropriate analytical technique. This strategy enables us to describe a dust mixture as a mixture of multinomial distributions over a fixed number of dust particle types. Using a latent Dirichlet allocation model, we make inference on (a) the contributions of sites of interest to a dust mixture, and (b) the particle profiles associated with these sites.
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Poeira/análise , Algoritmos , Teorema de Bayes , Modelos Teóricos , Distribuições EstatísticasRESUMO
Tumor progression, including metastasis, is significantly influenced by factors in the tumor microenvironment (TME) such as mechanical force, shear stress, chemotaxis, and hypoxia. At present, most cancer studies investigate tumor metastasis by conventional cell culture methods and animal models, which are limited in data interpretation. Although patient tissue analysis, such as human patient-derived xenografts (PDX), can provide important clinical relevant information, they may not be feasible for functional studies as they are costly and time-consuming. Thus, in vitro three-dimensional (3D) models are rapidly being developed that mimic TME and allow functional investigations of metastatic mechanisms and drug responses. One of those new 3D models is tumor-on-a-chip technology that provides a powerful in vitro platform for cancer research, with the ability to mimic the complex physiological architecture and precise spatiotemporal control. Tumor-on-a-chip technology can provide integrated features including 3D scaffolding, multicellular culture, and a vasculature system to simulate dynamic flow in vivo. Here, we review a select set of recent achievements in tumor-on-a-chip approaches and present potential directions for tumor-on-a-chip systems in the future for areas including mechanical and chemical mimetic systems. We also discuss challenges and perspectives in both biological factors and engineering methods for tumor-on-a-chip progress. These approaches will allow in the future for the tumor-on-a-chip systems to test therapeutic approaches for individuals through using their cancerous cells gathered through approaches like biopsies, which then will contribute toward personalized medicine treatments for improving their outcomes.
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Dispositivos Lab-On-A-Chip , Neoplasias , Animais , Técnicas de Cultura de Células , Humanos , Neoplasias/tratamento farmacológico , Medicina de Precisão , Microambiente TumoralRESUMO
Over the past decade, the field of forensic science has received recommendations from the National Research Council of the U.S. National Academy of Sciences, the U.S. National Institute of Standards and Technology, and the U.S. President's Council of Advisors on Science and Technology to study the validity and reliability of forensic analyses. More specifically, these committees recommend estimation of the rates of occurrence of erroneous conclusions drawn from forensic analyses. "Black box" studies for the various subjective feature-based comparison methods are intended for this purpose. In general, "black box" studies often have unbalanced designs, comparisons that are not independent, and missing data. These aspects pose difficulty in the analysis of the results and are often ignored. Instead, interpretation of the data relies on methods that assume independence between observations and a balanced experiment. Furthermore, all of these projects are interpreted within the frequentist framework and result in point estimates associated with confidence intervals that are confusing to communicate and understand. We propose to use an existing likelihood-free Bayesian inference method, called Approximate Bayesian Computation (ABC), that is capable of handling unbalanced designs, dependencies among the observations, and missing data. ABC allows for studying the parameters of interest without recourse to incoherent and misleading measures of uncertainty such as confidence intervals. By taking into account information from all decision categories for a given examiner and information from the population of examiners, our method also allows for quantifying the risk of error for the given examiner, even when no error has been recorded for that examiner. This opens the door to the detection of behavioural patterns in the decision-making of examiners through their ABC rate estimates. These patterns could be used to detect error prone examiners, enabling additional training efforts to be more tailored to each examiner, limiting the risk of errors before they occur. We illustrate our proposed method by reanalysing the results of the "Noblis Black Box" study by Ulery et al. [18]. We did not choose this study because we disagree with their results, but because it is a good example of a study with dependent observations and missing data, and the data is publicly available. The ABC estimates for the population generally agreed with Ulery et al.'s plug-in estimates. However, credible intervals obtained from ABC are much wider than the confidence intervals for the corresponding parameter estimates that did not account for the dependencies among observations.
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Arterial hypertension (AHT) is a major risk factor for stroke, yet blood pressure (BP) goals thereafter remain uncertain. Although additional prognostic value of 24-hour ambulant BP monitoring (ABPM) is acknowledged, its clinical impacts remain limited. We suspected that routine ABPM could identify characteristic circadian BP patterns in different brain lesion types, the knowledge of which might, in turn, be helpful in improving overall BP management in patients after stroke. In our study, we compared cardiovascular parameters derived from ABPM and traditional blood pressure measurements (TBPM) among 105 stroke survivors who entered our inpatient neuro-rehabilitation program. The mean age of mostly male (64.8%) patients was 71 ± 12 years. Ischemic strokes were predominant (75.2%). Despite normotensive systolic BP means in TBPM (133.5 ± 18.2 mmHg) and ABPM (24 h: 122.8 ± 14.7 mmHg), AHT persisted in up to 67.6% of all patients, with ABPM uncovering nocturnal systolic non- or reversed dipping in 89.5% and 53.3%, respectively. The latter was predominant (85.7%) in the hemorrhagic subgroup which also displayed lower daytime SBP than the ischemic one (ABPM: 117.1 ± 11.8 vs 124.7 ± 14.7 mmHg, p = 0.033). Further differences were present among distinct brain lesion types. Sufficient dippers were younger (58 ± 12 vs 75 ± 11 years, p < 0.001), but adjusting for age yielded no independent correlations. In spite of normotensive daytime BP measurements, ABPM detects latent AHT and insufficient nocturnal BP dipping after the acute phase of stroke. Further studies are needed to elucidate the role of increased nocturnal BP in patients after stroke.
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Hipertensão , Acidente Vascular Cerebral , Pressão Sanguínea , Monitorização Ambulatorial da Pressão Arterial , Criança , Ritmo Circadiano , Feminino , Humanos , Pacientes Internados , Masculino , Acidente Vascular Cerebral/diagnóstico , SobreviventesRESUMO
OBJECTIVES: Animal studies have suggested that exposure of the middle ear to topical local anaesthesia may be ototoxic. This study aimed to report sensorineural hearing outcomes and patients' satisfaction in those who underwent myringotomy and ventilation tube insertion using topical local anaesthesia. METHODS: Twenty-nine patients (32 ears) were operated on. Pre- and post-operative audiology findings were compared. A Likert-type questionnaire on treatment satisfaction was completed at the end of the procedure. RESULTS: Median patient age was 55 years (range, 27-88 years). Pre- and post-operative bone conduction pure tone averages were 26.76 dB and 25.26 dB respectively (mean reduction of -1.22 dB, 95 per cent confidence interval of -5.91 to 8.13 dB; p = 0.7538). One ear (3 per cent) had a reduction in pure tone average of 10 dB. CONCLUSION: The results suggest that sensorineural hearing loss is not a complication of ear exposure to topical local anaesthesia during myringotomy and ventilation tube insertion. The procedure was well perceived.
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Anestesia Local/efeitos adversos , Otopatias/cirurgia , Perda Auditiva Neurossensorial/diagnóstico , Ventilação da Orelha Média/métodos , Satisfação do Paciente/estatística & dados numéricos , Administração Tópica , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Perda Auditiva Neurossensorial/induzido quimicamente , Perda Auditiva Neurossensorial/epidemiologia , Testes Auditivos , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e QuestionáriosRESUMO
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
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BACKGROUND: Lipoprotein(a) (Lp(a)) is a genetic risk factor for cardiovascular disease (CVD) and is associated with the induction and sustaining of atherosclerotic cardiovascular diseases (ASCVD). Since 2008 Lp(a) along with progressive CVD has been approved as an indication for regular lipoprotein apheresis (LA) in Germany. The German Lipoprotein Apheresis Registry (GLAR) has been initiated to provide statistical evidence for the assessment of extracorporeal procedures to treat dyslipidemia for both LDL-cholesterol (LDL-C) and Lp(a). The GLAR now allows prospective investigations over a 5-year period about annual incidence rates of cardiovascular events. Here Lp(a) patients (LDL-Câ¯< 100â¯mg/dl; Lp(a)â¯> 60â¯mg/dl or >120â¯nmol/l) showed the same reduction of major coronary (83%) and non-coronary events (63%) as had been formerly shown in the Pro(a)LiFe study. However, Lp(a) is not only an apolipoprotein(a) (apo(a)) and LDL-C containing particle, which is covalently bound to a LDL-C core by a disulphide bridge. The composition of this particle, inter alia containing oxidized phospholipids, gives pro-atherosclerotic, pro-inflammatory, and pro-thrombotic properties, inducing atherosclerotic processes mainly in the arterial wall. However, recent investigations have shown that a reduction of inflammatory settings without LDL-C or Lp(a) reduction may reduce ASCVD events. Lipoprotein apheresis (LA) could not only reduce LDL-C and Lp(a) in parallel, but also different inflammatory and coagulation parameters. In summary lipoprotein apheresis is not only anti-atherosclerotic, but also anti-inflammatory and anti-thrombotic and therefore an ideal treatment option with respect to the shown reduction of major adverse coronary events (MACE) and major adverse non-coronary events (MANCE) by reducing Lp(a) levels.
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Aterosclerose/sangue , Remoção de Componentes Sanguíneos/métodos , Doenças Cardiovasculares/sangue , Lipoproteína(a)/sangue , Aterosclerose/genética , Aterosclerose/terapia , Doenças Cardiovasculares/genética , Doenças Cardiovasculares/terapia , LDL-Colesterol/sangue , Dislipidemias/terapia , Predisposição Genética para Doença , Alemanha , Humanos , Lipoproteína(a)/genética , Sistema de Registros , Fatores de RiscoRESUMO
Plasmonic biosensing has emerged as the most sensitive label-free technique to detect various molecular species in solutions and has already proved crucial in drug discovery, food safety and studies of bio-reactions. This technique relies on surface plasmon resonances in ~50 nm metallic films and the possibility to functionalize the surface of the metal in order to achieve selectivity. At the same time, most metals corrode in bio-solutions, which reduces the quality factor and darkness of plasmonic resonances and thus the sensitivity. Furthermore, functionalization itself might have a detrimental effect on the quality of the surface, also reducing sensitivity. Here we demonstrate that the use of graphene and other layered materials for passivation and functionalization broadens the range of metals which can be used for plasmonic biosensing and increases the sensitivity by 3-4 orders of magnitude, as it guarantees stability of a metal in liquid and preserves the plasmonic resonances under biofunctionalization. We use this approach to detect low molecular weight HT-2 toxins (crucial for food safety), achieving phase sensitivity~0.5 fg/mL, three orders of magnitude higher than previously reported. This proves that layered materials provide a new platform for surface plasmon resonance biosensing, paving the way for compact biosensors for point of care testing.
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A new experimental design for directional solidification experiments with high cooling rates under microgravity conditions is presented. The aerogel-based furnace module ARTEC (AeRogel TEchnology for Cast alloys) developed at DLR extends the earlier presented sounding rocket facility ARTEX by enabling a transition from low to high solidification velocities and a simultaneous operation of five independent furnaces in the same sounding rocket module. The furnaces for directional solidification are equipped with thermally insulating aerogels as a crucible material. Their optical transparency allows the control of the solidification parameters (velocity and temperature gradient) with optical methods in the lab. In ARTEC, a drastically increased solidification velocity is achieved by contacting the sample with a movable cooling-rod during processing. Therefore, a better theoretical understanding of the influence of a sudden change in solidification velocity on microstructure formation is obtained. Carrying out experiments in microgravity gives access to purely diffusive solidification conditions. Hence, convection free-growth can be compared with growth subject to natural (earth) and/or forced-convection (earth and space). Furthermore, alloys with high density differences in their alloy components and, hence, also between the primary solidifying phase and the surrounding liquid can be studied without the negative influence of fluid-flow or macrosegregation being present.