Sensor technologies can identify modified animal activity indicating changes in health status. This study investigated sheep behavior before and after illness caused by mold-contaminated feed using ...tri-axial accelerometers. Ten ewes were fitted with HerdDogg biometric accelerometers. Five ewes were concurrently fitted with Axivity AX3 accelerometers. The flock was exposed to mold-contaminated feed following an unexpected ration change, and observed symptomatic ewes were treated with a veterinarian-directed protocol. Accelerometer data were evaluated 4 days before exposure (d -4 to -1); the day of ration change (d 0); and 4 days post exposure (d 1 to 4). Herddogg activity index correlated to the variability of minimum and standard deviation of motion intensity monitored by the Axivity accelerometer. Herddogg activity index was lower (
< 0.05) during the mornings (0800 to 1100 h) of days 2 to 4 and the evening of day 1 than days -4 to 0. Symptomatic ewes had lower activity levels in the morning and higher levels at night. After accounting for symptoms, activity levels during days 1 to 4 were lower (
< 0.05) than days -4 to 0 the morning after exposure. Results suggest real-time or near-real time accelerometers have potential to detect illness in ewes.
In the framework of the modeling of composite beam structures, the eXtended Variational Formulation (XVF) is carried out to couple different kinematics. The purpose is to take advantages of efficient ...models and reduce the overall computational cost without loss of local precision. In this way, the structure is divided into non-overlapping domains with different kinematics. Local domains of interest are described with advanced models, such as refined Sinus model, to precisely describe local behavior, while the remaining global domain uses simple classical models. Each of the kinematics needs a suitable Finite Element (FE) approximation, therefore the coupling of different FE approximations is also addressed. The present approach is assessed on homogeneous and sandwich structures. It is compared with classical Multiple Point Constraints vias penalty. The study has shown the need of the introduction of a new operator for the layered structures. The results are very promising.
Here, we describe the surgical technique for implanting a new, active, transcutaneous bone conduction hearing aid. The implant technology is based on a system that has been in use reliably since ...2012. The geometry of the new implant has been adapted based on experience with previously introduced implants. The surgery was feasible, standardized, and safe. Due to the optimized geometric design that improved the bone fit, it is not necessary to use specialized, detailed preoperative planning, except in challenging anatomical conditions; e.g., in young children, malformations, poor pneumatization, or after a canal wall down mastoidectomy.
Leaf venation patterns vary considerably between species and between leaves within a species. A mechanism based on canalization of auxin transport has been suggested as the means by which plastic yet ...organized venation patterns are generated. This study assessed the plasticity of Arabidopsis thaliana leaf venation in response to ectopic ground or procambial cell divisions and auxin transport inhibition (ATI). Ectopic ground cell divisions resulted in vascular fragments between major veins, whereas ectopic procambial cell divisions resulted in additional, abnormal vessels along major veins, with more severely perturbed lines forming incomplete secondary and higher-order venation. These responses imply limited vascular plasticity in response to unscheduled cell divisions. Surprisingly, a combination of ectopic ground cell divisions and ATI resulted in massive vascular overgrowth. It is hypothesized that the vascular overproduction in auxin transport-inhibited wild-type leaves is limited by simultaneous differentiation of ground cells into mesophyll cells. Ectopic ground cell divisions may negate this effect by providing undifferentiated ground cells that respond to accumulated auxin by differentiation into vascular cells.
The capabilities and limitations of refined two-dimensional (2D) composite plate elements are discussed with respect to the stress concentration problem occurring at traction-free edges. Classical ...displacement-based and advanced partially mixed finite elements are formulated according to Carrera's Unified Formulation (CUF). Rectangular laminates are analyzed under extension and bending loading, where the attention is focused on the local stress response at the free edges. Present results are compared with reference results available in the literature and a 3D finite element model. A power law representation for a singular stress field is used to fit the obtained stresses in the vicinity of the free edge, and the parameters are used to assess the CUF elements and to compare the free-edge effect occurring in extension and bending.
The machining of ultra-precision optical components with form tolerances in the sub-micron range requires a close interaction between the machine tool, the process and the procedure for the NC tool ...path generation. Especially for the optical free-form machining the choice of a data-format for the surface description as well as the calculation of the tool path is crucial for the overall achievable quality of the work piece. This paper presents the layout of a tool path calculation based on the NURBS data format that has been developed at the Fraunhofer IPT. In addition the interfaces and the hardware and software for the realisation of a NURBS based control unit for Fast Tool Servo turning and local corrective polishing operations are described.
The myxobacterial polyketide secondary metabolites aurafuron A and B were identified by genome mining in the myxobacterial strain
Stigmatella aurantiaca DW4/3-1. The compounds contain an unusual ...furanone moiety and resemble metabolites isolated from soil-dwelling and marine actinobacteria, a fungus and mollusks. We describe here the cloning and functional analysis of the aurafuron biosynthetic gene cluster, including site-directed mutagenesis and feeding studies using labeled precursors. The polyketide core of the aurafurones is assembled by a modular polyketide synthase (PKS). As with many such systems described from myxobacteria, the aurafuron PKS exhibits a number of unusual features, including the apparent iterative use of a module, redundant modules and domains, a
trans acting dehydratase and the absence of a terminal thioesterase domain. Four oxidoreductases are encoded within the gene locus, some of which likely participate in formation of the furanone moiety
via a Baeyer–Villiger type oxidation. Indeed, inactivation of a gene encoding a cytochrome
P
450 monooxygenase completely abolished production of both compounds. We also compare the complete gene locus to biosynthetic gene clusters from two
Streptomyces sp., which produce close structural analogues of the aurafurones. A portion of the post-PKS biosynthetic machinery is strikingly similar in all three cases, in contrast to the PKS genes, which are highly divergent. Phylogenetic analysis of the ketosynthase domains further indicates that the PKSs have developed independently (polyphyletically) during evolution. These findings point to a currently unknown but important biological function of aurafuron-like compounds for the producing organisms.
This paper addresses the development of performance-based assessment items for ICT skills, skills in dealing with information and communication technologies, a construct which is rather broadly and ...only operationally defined. Item development followed a construct-driven approach to ensure that test scores could be interpreted as intended. Specifically, ICT-specific knowledge as well as problem-solving and the comprehension of text and graphics were defined as components of ICT skills and cognitive ICT tasks (i.e., accessing, managing, integrating, evaluating, creating). In order to capture the construct in a valid way, design principles for constructing the simulation environment and response format were formulated. To empirically evaluate the very heterogeneous items and detect malfunctioning items, item difficulties were analyzed and behavior-related indicators with item-specific thresholds were developed and applied. The 69 item’s difficulty scores from the Rasch model fell within a comparable range for each cognitive task. Process indicators addressing time use and test-taker interactions were used to analyze whether most test-takers executed the intended processes, exhibited disengagement, or got lost among the items. Most items were capable of eliciting the intended behavior; for the few exceptions, conclusions for item revisions were drawn. The results affirm the utility of the proposed framework for developing and implementing performance-based items to assess ICT skills.
The barley pathogen Rhynchosporium commune secretes necrosis-inducing proteins NIP1, NIP2, and NIP3. Expression analysis revealed that NIP1 transcripts appear to be present in fungal spores already, ...whereas NIP2 and NIP3 are synthesized after inoculation of host plants. To assess the contribution of the three effector proteins to disease development, deletion mutants were generated. The development of these fungal mutants on four barley cultivars was quantified in comparison with that of the parent wild-type strain and with two fungal strains failing to secrete an "active" NIP1 avirulence protein, using quantitative polymerase chain reaction as well as microscopic imaging after fungal green fluorescent protein tagging. The impact of the three deletions varied quantitatively depending on the host genotype, suggesting that the activities of the fungal effectors add up to produce stronger growth patterns and symptom development. Alternatively, recognition events of differing intensities may be converted into defense gene expression in a quantitative manner.
Corallopyronins (COR) are α-pyrone antibiotics from myxobacteria representing highly promising lead structures for the development of antibacterial therapeutic agents. Their ability to inhibit RNA ...polymerase through interaction with the “switch region”, a novel target, distant from binding sites of previously characterized RNA polymerase inhibitors (e.g. rifampicin), makes them particularly promising as antibiotic candidates. Corallopyronin A is currently also investigated as a lead compound for the treatment of lymphatic filariasis because of its superb activity against the nematode symbiont Wolbachia. As total synthesis is not a valid production option biotechnological optimization of compound supply is of utmost importance to further develop this highly potent compound class.
Here we describe decisive improvements of the previously reported heterologous COR production and engineering platform yielding production of ~100 mg/L COR A. Furthermore, we provide a revised model of COR biosynthesis shedding light on the function of several biosynthetic proteins, including an unusual ECH-like enzyme providing dehydration functionality in trans and an uncharacterized protein conferring COR self-resistance in the myxobacterial heterologous host Myxococcus xanthus DK1622. We also report two new COR derivatives, COR D and oxyCOR A discovered in genetically engineered strains.
•Total corallopyronin yield increased threefold by promoter exchange.•Revision of corallopyronin biosynthesis.•Isolation and structure elucidation of two novel corallopyronin derivatives.•Identification of a novel self-resistance determinant for myxobacterial RNAP inhibitors.
PDF
