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Summary: Epiphytic microbes frequently affect plant phenotype and fitness, but their effects depend on microbe abundance and community composition. Filtering by plant traits and deterministic dispersal‐mediated processes can affect microbiome assembly, yet their relative contribution to predictable variation in microbiome is poorly understood.We compared the effects of host‐plant filtering and dispersal on nectar microbiome presence, abundance, and composition. We inoculated representative bacteria and yeast into 30 plants across four phenotypically distinct cultivars of Epilobium canum. We compared the growth of inoculated communities to openly visited flowers from a subset of the same plants.There was clear evidence of host selection when we inoculated flowers with synthetic communities. However, plants with the highest microbial densities when inoculated did not have the highest microbial densities when openly visited. Instead, plants predictably varied in the presence of bacteria, which was correlated with pollen receipt and floral traits, suggesting a role for deterministic dispersal.These findings suggest that host filtering could drive plant microbiome assembly in tissues where species pools are large and dispersal is high. However, deterministic differences in microbial dispersal to hosts may be equally or more important when microbes rely on an animal vector, dispersal is low, or arrival order is important. [ABSTRACT FROM AUTHOR]

Floral nectar is frequently colonised by microbes. However, nectar microbial communities are typically species‐poor and dominated by few cosmopolitan genera. One hypothesis is that nectar constituents may act as environmental filters. We tested how five non‐sugar nectar compounds as well as elevated sugar impacted the growth of 12 fungal and bacterial species isolated from nectar, pollinators, and the environment. We hypothesised that nectar isolated microbes would have the least growth suppression. Additionally, to test if nectar compounds could affect the outcome of competition between microbes, we grew a subset of microbes in co‐culture across a subset of treatments. We found that some compounds such as H2O2 suppressed microbial growth across many but not all microbes tested. Other compounds were more specialised in the microbes they impacted. As hypothesised, the nectar specialist yeast Metschnikowia reukaufii was unaffected by most nectar compounds assayed. However, many non‐nectar specialist microbes remained unaffected by nectar compounds thought to reduce microbial growth. Our results show that nectar chemistry can influence microbial communities but that microbe‐specific responses to nectar compounds are common. Nectar chemistry also affected the outcome of species interactions among microbial taxa, suggesting that non‐sugar compounds can affect microbial community assembly in flowers. [ABSTRACT FROM AUTHOR]

Hydrogen is a promising fuel to decarbonize aviation, but macroeconomic studies are currently missing. Computable general equilibrium (CGE) models are suitable to conduct macroeconomic analyses and are frequently employed in hydrogen and aviation research. The main objective of this paper is to investigate existing CGE studies related to (a) hydrogen and (b) aviation to derive a macroeconomic research agenda for hydrogen-powered aviation. Therefore, the well-established method of systematic literature review is conducted. First, we provide an overview of 18 hydrogen-related and 27 aviation-related CGE studies and analyze the literature with respect to appropriate categories. Second, we highlight key insights and identify research gaps for both the hydrogen- and aviation-related CGE literature. Our findings comprise, inter alia, hydrogen's current lack of cost competitiveness and the macroeconomic relevance of air transportation. Research gaps include, among others, a stronger focus on sustainable hydrogen and a more holistic perspective on the air transportation system. Third, we derive implications for macroeconomic research on hydrogen-powered aviation, including (I) the consideration of existing modeling approaches, (II) the utilization of interdisciplinary data and scenarios, (III) geographical suitability, (IV) the application of diverse policy tools and (V) a holistic perspective. Our work contributes a meaningful foundation for macroeconomic studies on hydrogen-powered aviation. Moreover, we recommend policymakers to address the macroeconomic perspectives of hydrogen use in air transportation. [ABSTRACT FROM AUTHOR]

TV series such as “House MD”, “Grey´s Anatomy” or “Emergency Room” are well perceived by medical students. Seminars featuring medical TV series such as “House MD” might serve as door-opener to attract medical students to learn more about rare diseases. The TV series “House MD” is troublesome for the main character Dr. House is an excellent diagnostician but at the same time a rather misanthropic person. Therefore, lecturing medicine with the help of “House MD” requires constant evaluation. From 2008 to 2016 we are using the well-known TV series “House MD” continuously to attract medical students and teach them about rare diseases as well as diagnostic strategies. We collected from 213 students a detailed questionnaire assessing their learning experience. 76.6% of our students (n = 157) reported to watching medical dramas on a regular basis. The Dr. House seminar was compared to traditional seminars and our students reported an improved learning effect (69.9%), better concentration (89.7%), higher motivation to participate (88.7%), and more fun (86.7%) (all p<0.001). The students see Dr. House’s behavior quite critically. Likert assessment on a 5-point scale identified strong disagreement with Dr. House´s interpersonal skills in dealing with his colleagues (median = 1) and patients (median = 1). At the same time, the students strongly agreed with his outstanding diagnostic (median = 5) and therapeutic capabilities (median = 4). Medical students visiting a Dr. House teaching seminar are highly motivated to learn more about rare diseases. They were positively influenced by TV series such as Dr. House to improve their diagnostic and clinical skills. At the same time, they are critical enough not to see Dr. House as a role model for their own personality. Well performed medical TV shows such as Dr. House can successfully be used in an educational setting to motivate medical students to come into seminars to learn more about rare diseases. [ABSTRACT FROM AUTHOR]

Background: Little is known about the characteristics of patients seeking help from dedicated centers for undiagnosed and rare diseases. However, information about their demographics, symptoms, prior diagnoses and medical specialty is crucial to optimize these centers' processes and infrastructure.Methods: Using a questionnaire, structured information from 522 adult patients contacting a center for undiagnosed and rare diseases was obtained. The information included basic sociodemographic data (age, gender, insurance status), previous hospital admissions, primary symptoms of complaint and previously determined diagnosis.Results: The majority of patients completing the questionnaire were female, 300 (57 %) vs. 222 men (43 %). The median age was 52 years (range 18-92). More than half, 309 (59 %), of our patients had never been admitted to a university hospital. Common diagnoses included other soft tissue disorders, not classified elsewhere (ICD M79, n = 63, 15.3 %), somatoform disorders (ICD F45, n = 51, 12.3 %) and other polyneuropathies (ICD G62, n=36, 8.7 %). The most frequent symptoms were general weakness (n = 180, 36.6 %) followed by arthralgia (n = 124, 25.2 %) and abdominal discomfort (n = 113, 23.0 %). The majority of patients had either internal medicine (81.3 %) and/or neurologic (37.6 %) health problems.Conclusions: Pain-associated diagnoses and the typical "unexplained" medical conditions (chronic fatigue syndrome, fibromyalgia, irritable bowel syndrome) are frequent among people contacting a center dedicated to undiagnosed diseases. The chief symptoms are mostly unspecific. An interdisciplinary organizational approach involving mainly internal medicine, neurology and psychiatry/psychosomatic care is needed. [ABSTRACT FROM AUTHOR]

Microbial pathogens have developed several mechanisms to modulate and interfere with host cell cycle progression. In this study, we analysed the effect of the human pathogen Neisseria meningitidis on cell cycle in a brain endothelial cell line as well as in primary brain endothelial cells. We found that N. meningitidis causes an accumulation of cells in the S phase early at 3 and at 24 h post-infection that was paralleled by a decrease of cells in G2/M phase. Importantly, the outer membrane proteins of the colony opacity-associated (Opa) protein family as well as the Opc protein proved to trigger the accumulation of cells in the S phase. A focused cell cycle reverse transcription quantitative polymerase chain reaction-based array and integrated network analysis revealed changes in the abundance of several cell cycle regulatory mRNAs, including the cell cycle inhibitors p21WAF1/CIP1 and cyclin G2. These alterations were reflected in changes in protein expression levels and/or relocalization in N. meningitidis-infected cells. Moreover, an increase in p21WAF1/CIP1 expression was found to be p53 independent. Genetic ablation of p21WAF1/CIP1 and cyclin G2 abrogated N. meningitidis-induced S phase accumulation. Finally, by measuring the levels of the biomarker 8-hydroxydeoxyguanosine and phosphorylation of the histone variant H2AX, we provide evidence that N. meningitidis induces oxidative DNA damage in infected cells. [ABSTRACT FROM AUTHOR]

While Botrytis cinerea causes gray mold on many plants, its close relative, Botrytis fabae, is host-specifically infecting predominantly faba bean plants. To explore the basis for its narrow host range, a gapless genome sequence of B. fabae strain G12 (BfabG12) was generated. The BfabG12 genome encompasses 45.0 Mb, with 16 chromosomal telomere-to-telomere contigs that show high synteny and sequence similarity to the corresponding B. cinerea B05.10 (BcB0510) chromosomes. Compared to BcB0510, it is 6% larger, due to many AT-rich regions containing remnants of transposable elements, but encodes fewer genes (11,420 vs. 11,707), due to losses of chromosomal segments with up to 20 genes. The coding capacity of BfabG12 is further reduced by nearly 400 genes that had been inactivated by mutations leading to truncations compared to their BcB0510 orthologues. Several species-specific gene clusters for secondary metabolite biosynthesis with stage-specific expression were identified. Comparison of the proteins secreted during infection revealed high similarities, including 17 phytotoxic proteins that were detected in both species. Our data indicate that evolution of the host-specific B. fabae occurred from an ancestral pathogen with wide host range similar to B. cinerea and was accompanied by losses and degeneration of genes, thereby reducing its pathogenic flexibility. [ABSTRACT FROM AUTHOR]

The present paper reports on the development of a biodegradable overmolded orthopedic implant: a metal bone fixing screw, which has been overmolded with a functionalized thin layer of biodegradable polymer to enhance cell adhesion during the healing process. The main challenges were to integrate precise, high-throughput and repeatable solutions to achieve a thin, defect-free structured polymer layer and to ensure a high and consistent implant quality. The work carried out entailed determining proper materials (Purasorb PDLG 5010) for the biodegradable overmolding layer and its economical substitute (NaKu PLA 100HF) to be used during initial tool and process development, designing the surface structure of the overmolded polymer layer, development of injection molding tools, as well as feeding and handling procedures. The injection overmolding process of Purasorb PDLG 5010 polymer was controlled, and the process parameters were optimized. In particular, the dominant process parameters for the overmolding, namely injection pressure, barrel temperature and mold temperature, were experimentally examined using a circumscribed three-factor central composite design and two quality marks; overmolding roughness and mass of polymer. The analysis of the experimental results shows that the mass of the overmolding is not feasible for use as the quality mark. However, the optimal parameters for the overmolding of a metallic implant screw with a thin, micro-structured polymer layer with a predefined roughness of the surface texture have been identified successfully. [ABSTRACT FROM AUTHOR]

The soluble urokinase-type plasminogen activator receptor (suPAR) has evolved as a useful biomarker for different entities of chronic liver disease. However, its role in patients with primary sclerosing cholangitis (PSC) is obscure. We analyzed plasma levels of suPAR in 84 patients with PSC and compared them to 68 patients with inflammatory bowel disease (IBD) without PSC and to 40 healthy controls. Results are correlated with clinical records. suPAR concentrations were elevated in patients with PSC compared to patients with IBD only and to healthy controls (p < 0.001). Elevated suPAR levels were associated with the presence of liver cirrhosis (p < 0.001) and signs of portal hypertension (p < 0.001). suPAR revealed a high accuracy for the discrimination of the presence of liver cirrhosis comparable to previously validated noninvasive fibrosis markers (area under the curve (AUC) 0.802 (95%CI: 0.702–0.902)). Further, we demonstrated that suPAR levels may indicate the presence of acute cholangitis episodes (p < 0.001). Finally, despite the high proportion of PSC patients with IBD, presence of IBD and its disease activity did not influence circulating suPAR levels. suPAR represents a previously unrecognized biomarker for diagnosis and liver cirrhosis detection in patients with PSC. However, it does not appear to be confounded by intestinal inflammation in the context of IBD. [ABSTRACT FROM AUTHOR]

Variation in dispersal ability among taxa affects community assembly and biodiversity maintenance within metacommunities. Although fungi and bacteria frequently coexist, their relative dispersal abilities are poorly understood. Nectar-inhabiting microbial communities affect plant reproduction and pollinator behavior, and are excellent models for studying dispersal of bacteria and fungi in a metacommunity framework. Here, we assay dispersal ability of common nectar bacteria and fungi in an insect-based dispersal experiment. We then compare these results with the incidence and abundance of culturable flower-inhabiting bacteria and fungi within naturally occurring flowers across two coflowering communities in California across two flowering seasons. Our microbial dispersal experiment demonstrates that bacteria disperse via thrips among artificial habitat patches more readily than fungi. In the field, incidence and abundance of culturable bacteria and fungi were positively correlated, but bacteria were much more widespread. These patterns suggest shared dispersal routes or habitat requirements among culturable bacteria and fungi, but differences in dispersal or colonization frequency by thrips, common flower visitors. The finding that culturable bacteria are more common among nectar sampled here, in part due to superior thrips-mediated dispersal, may have relevance for microbial life history, community assembly of microbes, and plant–pollinator interactions. [ABSTRACT FROM AUTHOR]

Background: The endoplasmic reticulum (ER) is the cellular site for protein folding. ER stress occurs when protein folding capacity is exceeded. This stress induces a cyto-protective signaling cascades termed the unfolded protein response (UPR) aimed at restoring homeostasis. While acute ER stress is lethal, chronic sub-lethal ER stress causes cells to adapt by attenuation of UPR activation. Hepatitis C virus (HCV), a major human pathogen, was shown to cause ER stress, however it is unclear whether HCV induces chronic ER stress, and if so whether adaptation mechanisms are initiated. We wanted to characterize the kinetics of HCV-induced ER stress during infection and assess adaptation mechanisms and their significance. Methods and Findings: The HuH7.5.1 cellular system and HCV-transgenic (HCV-Tg) mice were used to characterize HCVinduced ER stress/UPR pathway activation and adaptation. HCV induced a wave of acute ER stress peaking 2-5 days postinfection, which rapidly subsided thereafter. UPR pathways were activated including IRE1 and EIF2α phosphorylation, ATF6 cleavage and XBP-1 splicing. Downstream target genes including GADD34, ERdj4, p58ipk, ATF3 and ATF4 were upregulated. CHOP, a UPR regulated protein was activated and translocated to the nucleus. Remarkably, UPR activity did not return to baseline but remained elevated for up to 14 days post infection suggesting that chronic ER stress is induced. At this time, cells adapted to ER stress and were less responsive to further drug-induced ER stress. Similar results were obtained in HCVTg mice. Suppression of HCV by Interferon-α 2a treatment, restored UPR responsiveness to ER stress tolerant cells. Conclusions: Our study shows, for the first time, that HCV induces adaptation to chronic ER stress which was reversed upon viral suppression. These finding represent a novel viral mechanism to manipulate cellular response pathways. [ABSTRACT FROM AUTHOR]

Recently CC chemokine receptor 5 (CCR5) related immune mechanisms and a functional mutation of the CCR5 gene have been implicated in hepatitis C virus (HCV) infection in a cohort of predominantly hemophiliac patients. The present study investigated the frequency and clinical consequences of the CCR5 Δ32 mutation in two genetically homogeneous populations of HCV infected patients with a different risk profile for infection. Genomic DNA samples from 333 German patients with chronic HCV infection were screened by PCR for the presence of the CCR5 Δ32 polymorphism. In-hospital patients admitted for other diseases than viral hepatitis but with a comparable risk for HCV exposure were used as control population (n=125). Allele frequencies of CCR5 Δ32 polymorphism did not differ significantly between the two groups (7.6% and 9.5%, respectively) and control subjects (10.4%), and did not deviate from Hardy-Weinberg equilibrium in any group. Furthermore, there were no major differences between patients with respect to HCV genotypes, viral loads, liver enzymes, or fibrosis scores in relation to the presence or absence of the heterozygous CCR5 Δ32 mutation. Differences in inflammatory scores in liver biopsy samples and response to antiviral therapy in CCR5 Δ32 heterozygotes in one cohort could neither be reproduced in the other group of patients nor when both cohorts were pooled. These results argue against a strong effect of the CCR5 Δ32 deletion regarding these phenotypes. In conclusion, we found no increased frequency of the CCR5 Δ32 polymorphism in two independent cohorts of patients with HCV infection but without hemophilia as the main risk factor for infection. As the major difference to investigations demonstrating an association between CCR5 Δ32 and HCV infection is the selection of cases and controls, our study emphasizes the importance of epidemiological criteria for association studies of HCV infection. [ABSTRACT FROM AUTHOR]

African trypanosomes cause sleeping sickness in humans and nagana in cattle. These unicellular parasites are transmitted by the bloodsucking tsetse fly. In the mammalian host's circulation, proliferating slender stage cells differentiate into cell cycle-arrested stumpy stage cells when they reach high population densities. This stage transition is thought to fulfil two main functions: first, it auto-regulates the parasite load in the host; second, the stumpy stage is regarded as the only stage capable of successful vector transmission. Here, we show that proliferating slender stage trypanosomes express the mRNA and protein of a known stumpy stage marker, complete the complex life cycle in the fly as successfully as the stumpy stage, and require only a single parasite for productive infection. These findings suggest a reassessment of the traditional view of the trypanosome life cycle. They may also provide a solution to a long-lasting paradox, namely the successful transmission of parasites in chronic infections, despite low parasitemia. [ABSTRACT FROM AUTHOR]

Background: The increasing popularity and availability of tablet computers raises questions regarding clinical scenarios. This pilot study examined the patient's satisfaction when using a tablet-based digital questionnaire as a tool for obtaining medical history in an emergency department and to what extent gender, age, technical competence and mother tongue influence the user satisfaction. Patients were asked to complete three consecutive questionnaires: The first questionnaire collected basic epidemiological data to measure past digital usage behaviour, the second questionnaire collected the patient's medical history, and the third questionnaire assessed the overall perceived user satisfaction when using the tablet-based survey application for medical anamnesis.Results: Of 111 consenting patients, 86 completed all three questionnaires. In summary, the user evaluation was positive with 97.7% (n = 84) of the patients stating that they had no major difficulties using the digital questionnaire. Only 8.1% (n = 7) of patients reported a preference to fill out a paper-and-pen version on the next visit instead, while 98.8% (n = 85) stated that they would feel confident filling out a digital questionnaire on the next visit. The variables gender, age, mother tongue and/or technical competence did not exert a statistically significant influence towards the defined scales usability, content and overall impression.Conclusion: In conclusion, self-administered tablet-based questionnaires are widely accepted tools for collecting medical information in the emergency room across all ages and genders, regardless of technical competence. [ABSTRACT FROM AUTHOR]

Background: Foodborne botulism is a life-threatening, rapidly progressive disease. It has an incidence of less than 10 cases per year in Germany and mostly affects several previously healthy people at the same time. The only specific treatment is the administration of botulism antitoxin. According to the German guidelines administration of antitoxin is recommended only in the first 24 hours after oral ingestion of the toxin.Case Presentation: A 47-year-old white woman and her 51-year-old white husband presented with paralysis of multiple cranial nerves and rapidly descending paralysis approximately 72 hours after ingestion of home-canned beans. The disease was complicated by autonomic changes like hypertension, febrile temperatures, and a paralytic ileus. The diagnosis was confirmed by identification of botulinum neurotoxin type A in the serum of the woman. In accordance with the German guidelines, antitoxin was not given due to the prolonged time interval at diagnosis. Both patients had a long intensive care unit course requiring ventilation for approximately 5 months. Finally they recovered completely.Conclusions: A full recovery from foodborne botulism is possible even in patients with intensive care lasting several months. There are only case reports indicating that administration of antitoxin may shorten the course of the disease, even if given later than 24 hours after intoxication. Due to the rarity of the disease and its rapid course there are no randomized controlled trials. Thus, evidence of the superiority of this treatment is lacking. However, the prevailing view according to the German guidelines to administer antitoxin only within 24 hours after ingestion of the toxin should be questioned in the case of progression of the disease with proof of remaining toxin in the blood. [ABSTRACT FROM AUTHOR]

The initial stages of the interaction between the host and Aspergillus fumigatus at the alveolar surface of the human lung are critical in the establishment of aspergillosis. Using an in vitro bilayer model of the alveolus, including both the epithelium (human lung adenocarcinoma epithelial cell line, A549) and endothelium (human pulmonary artery epithelial cells, HPAEC) on transwell membranes, it was possible to closely replicate the in vivo conditions. Two distinct sub-groups of dendritic cells (DC), monocyte-derived DC (moDC) and myeloid DC (mDC), were included in the model to examine immune responses to fungal infection at the alveolar surface. RNA in high quantity and quality was extracted from the cell layers on the transwell membrane to allow gene expression analysis using tailored custom-made microarrays, containing probes for 117 immune-relevant genes. This microarray data indicated minimal induction of immune gene expression in A549 alveolar epithelial cells in response to germ tubes of A. fumigatus. In contrast, the addition of DC to the system greatly increased the number of differentially expressed immune genes. moDC exhibited increased expression of genes including CLEC7A, CD209 and CCL18 in the absence of A. fumigatus compared to mDC. In the presence of A. fumigatus, both DC subgroups exhibited up-regulation of genes identified in previous studies as being associated with the exposure of DC to A. fumigatus and exhibiting chemotactic properties for neutrophils, including CXCL2, CXCL5, CCL20, and IL1B. This model closely approximated the human alveolus allowing for an analysis of the host pathogen interface that complements existing animal models of IA. [ABSTRACT FROM AUTHOR]

Background and Aims: C/EBP homologous protein (CHOP) plays pro-apoptotic roles in the integrated stress response. Recently, a tumor suppressive role for CHOP was demonstrated in lung cancer via regulation of tumor metabolism. To explore the role of CHOP in hepatocarcinogenesis, we induced hepatocellular carcinoma (HCC) in wild type (wt) and CHOP knockout (KO) mice using the carcinogen N-diethylnitrosamine (DEN). Results: Analysis of tumor development showed reduced tumor load, with markedly smaller tumor nodules in the CHOP KO animals, suggesting oncogenic roles of CHOP in carcinogen-induced HCC. In wt tumors, CHOP was exclusively expressed in tumor tissue, with minimal expression in normal parenchyma. Analysis of human adenocarcinomas of various origins demonstrated scattered expression of CHOP in the tumors, pointing to relevance in human pathology. Characterization of pathways that may contribute to preferential expression of CHOP in the tumor identified ATF6 as a potential candidate. ATF6, a key member of the endoplasmic reticulum stress signaling machinery, exhibited a similar pattern of expression as CHOP and strong activation in wt but not CHOP KO tumors. Because HCC is induced by chronic inflammation, we assessed whether CHOP deficiency affects tumor-immune system crosstalk. We found that the number of macrophages and levels of IFNγ and CCL4 mRNA were markedly reduced in tumors from CHOP KO relative to wt mice, suggesting a role for CHOP in modulating tumor microenvironment and macrophage recruitment to the tumor. Conclusion: Our data highlights a role for CHOP as a positive regulator of carcinogen-induced HCC progression through a complex mechanism that involves the immune system and modulation of stress signaling pathways. [ABSTRACT FROM AUTHOR]

Members of the guanine exchange factor (GEF) family of scaffold proteins are involved in the integration of signal flow down-stream of many receptors in adaptive immunity. However, the full complement of GEFs that function downstream of Toll-like receptors (TLRs) requires further identification and functional understanding. By systematically integrating expression profiles from immune and epithelial cells with functional studies, we demonstrate that protein kinase A anchoring protein 13 (AKAP13), a scaffold protein with GEF activity, is an activator of NF-κB downstream of TLR2 signaling. Stimulation of the human macrophage cell line THP-1 and epithelial cells with a TLR2 ligand caused a significant up-regulation in AKAP13 mRNA, corresponding to an increase in protein expression. Analysis of TLR2 reporter cell lines deficient in AKAP13 expression revealed significantly reduced NF-κB activation and reduced secretion of interleukin-8 and MCP-1 in response to specific ligand stimulation. Furthermore, NF-κB activation was partially inhibited by a GEF-deficient AKAP13 mutant. AKAP13 was also involved in phosphorylation of JNK but not of extracellular signal-regulated kinase ERK1 and -2 following ligand stimulation. Together, our results suggest that AKAP13 plays a role in TLR2-mediated NF-κB activation and suggest that GEF-containing scaffold proteins may confer specificity to innate immune responses downstream of TLRs. [ABSTRACT FROM AUTHOR]

A process for the development, characterization and correlation of composite materials for 3D printing is presented, alongside the processing of a polymer-ceramic functional composite using fused deposition modeling (FDM). The composite was developed using acrylonitrile butadiene styrene (ABS) as the matrix material filled with barium titanate (BT) micro-powder up to 35 vol % (74.2 wt %). The ABS-BT composites exhibited a shear thinning behavior with increasing ceramic content. The composite was 3D printed into structural and functional test samples using FDM by adapting and optimizing the print parameters. Structural characterization revealed increasingly brittle behavior at higher filler ratios, with the ultimate tensile strength falling from 25.5 MPa for pure ABS to 13.7 MPa for the ABS-35 vol % BT composite. Four-point flexural tests showed a similar decrease in flexural strength with increasing ceramic content. Functional characterization revealed an increase in the relative permittivity at 200 kHz from 3.08 for pure ABS to 11.5 for the composite with 35 vol % BT. These results were correlated with the Maxwell-Garnett and Jayasundere-Smith effective medium models. The process described in this work can be used for other 3D printing processes and provides a framework for the rapid prototyping of functional composites into functional parts with reliable properties. The ABS-BT composite shows promise as a functional dielectric material, with potential applications as capacitors and light-weight passive antennas. [ABSTRACT FROM AUTHOR]