Entwicklung eines Konzepts für eine nachgiebige Kopplung zweier Segmente eines aquatischen Roboters

Abstract This diploma thesis presents the development, construction and testing of a new variant of a passively adjustable compliant joint. This joint is located between the modules of a modular swimming robot. The locomotion of this robot is biologically inspired. At the moment, there are two possible movement patterns: an eel-like (anguilliform) locomotion and a thuna-like (thunniform) locomotion. The robot consists of a two module base structure. A variable number of effector modules can be connected with these base modules. The base structure carries the power supply, the receiver for the remote control, the motor controller and the single drive. The number of the effector modules defines the movement patterns (anguilliform or thunniform). The coupling of the effector modules is mechanically executed. The utilised compliant joint is the focal point of this thesis. The new design is based on the plane bending of linear spring steel sheets in contrast to the current pattern with linear spiral springs. Two variants are constructed, one with two parallel spring steel sheets and one with a single centered spring steel sheet. Especially the single centered spring steel sheet variant enables the tail structure with three modules to perform anguilliform motions. Furthermore, the first steps for a sensory recording of current and voltage of the single drive actuated swimming robot are undertaken. A measuring circuit is designed, produced and programmed. This circuit delivers exact results of the current that is consumed by the motor. The results are sent to a PC via USB cable and connector. In addition to that, a variant for a modular connector that can carry the compliant joint and connects the joint with the robot’s body is constructed and a first sample is built and tested. The sample build of the modular connector is waterproof and presents an alternative to the current design.Zusammenfassung Diese Diplomarbeit stellt die Entwicklung, die Konstruktion und den Test einer neuen Variante eines Gelenks mit passiv einstellbarer Elastizität vor. Das Gelenk befindet sich zwischen den Modulen eines modularen aquatischen Roboters. Die Lokomotion dieses Roboters ist biologisch inspiriert, derzeitig ist eine aal-ähnliche (anguilliforme) und eine thunfisch-ähnliche (thunniforme) Fortbewegung möglich. Hierfür besteht der Roboter aus einer Basisstruktur an welche eine variable Anzahl an Effektormodulen anschließbar ist. Die Basisstruktur beinhaltet die Energieversorgung, den Empfänger für die Fernsteuerung, den Motorregler und den Antrieb selbst. Die Anzahl der Effektormodule definiert dabei die Fortbewegungsart (anguilliform bzw. thunniform), die Kopplung der Effektormodule untereinander erfolgt mechanisch. Das hierbei verwendete nachgiebige Gelenk ist Schwerpunkt der vorliegenden Arbeit. Das entworfene Design basiert dabei - im Gegensatz zur derzeitigen Gestaltung mit linearen Schraubenfedern - auf der geraden Biegung von linearen Federblechen. Es werden zwei verschiedene Varianten gebaut, eine mit zwei parallelen Federblechen und eine mit einem zentralen Federblech. Dabei ermöglicht insbesondere die Variante mit dem zentralen Federblech eine anguilliforme Bewegung der Effektormodule. Des Weiteren erfolgt eine erste sensorische Erfassung von Strom und Spannung des aquatischen Roboters. Eine elektrische Schaltung wird entworfen, aufgebaut und programmiert. Die Messschaltung liefert exakte Ergebnisse bei der Strommessung. Mittels USB-Schnittstelle sendet die Schaltung die Messwerte an den PC. Zusätzlich finden die Konstruktion und der Test einer Variante eines modularen Verbinders zwischen Effektormodul und nachgiebiger Kopplung statt. Der Testaufbau der modularen Verbindung erweist sich als wasserdicht und stellt eine Alternative zum aktuellen Design dar.Zugl.: Ilmenau, Techn. Univ., Diplomarbeit, 201

The paleogeography of the Middle and Upper Silurian period in southeastern Michigan

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The relationship between internalized homophobia and psychological distress in lesbians

Growing up and living in a homophobic society, lesbians are\ud exposed to numerous negative attitudes, assumptions, and messages\ud concerning homosexuality. Internalized homophobia refers to the\ud incorporation of these homophobic beliefs within the lesbian's self-image.\ud Internalized homophobia is assumed to be associated with psychological\ud distress and as presenting a significant threat to healthy self-esteem and\ud identity development in lesbians\ud The purpose of the present study was to examine the association\ud between internalized homophobia and psychological distress in lesbians.\ud Participants were self-identified lesbians residing in one of three cities: a\ud small rural city; a mid-sized city; or a large metropolitan area. The data\ud consisted of participant scores on the Symptom Checklist 90-Revised\ud (SCL-90-R) and the Internalized Homophobia Scale for Lesbians (IHSL) .\ud Results of this study indicated general internalized homophobia\ud significantly correlated with overall psychological distress as well as with\ud depression in lesbians. The findings also indicated that psychological\ud \ud distress was associated with younger age, medication usage, lower\ud income, nega tive attitudes toward other lesbians and non-white\ud ethnicity. In addition, results indicated participants from the smallest\ud city in the sample displayed significantly higher levels of internalized\ud homophobia compared to participants from the other cities.\ud This research demonstrated internalized homophobia is a salient\ud factor in the lives of lesbians and needs to be addressed when\ud researching identity development and psychological functioning in\ud lesbians. Additionally, this study pointed to the need for therapists who\ud work with lesbians to have a clear understanding of internalized\ud homophobia and skills in helping lesbians deal with this issue.Stabb, Sally Dr.\ud Nutt, Roberta Dr.\ud Rubin, Linda Dr.\ud Miller, Daniel Dr

AI algorithm for personalized resource allocation and treatment of hemorrhage casualties

A deep neural network-based artificial intelligence (AI) model was assessed for its utility in predicting vital signs of hemorrhage patients and optimizing the management of fluid resuscitation in mass casualties. With the use of a cardio-respiratory computational model to generate synthetic data of hemorrhage casualties, an application was created where a limited data stream (the initial 10 min of vital-sign monitoring) could be used to predict the outcomes of different fluid resuscitation allocations 60 min into the future. The predicted outcomes were then used to select the optimal resuscitation allocation for various simulated mass-casualty scenarios. This allowed the assessment of the potential benefits of using an allocation method based on personalized predictions of future vital signs versus a static population-based method that only uses currently available vital-sign information. The theoretical benefits of this approach included up to 46% additional casualties restored to healthy vital signs and a 119% increase in fluid-utilization efficiency. Although the study is not immune from limitations associated with synthetic data under specific assumptions, the work demonstrated the potential for incorporating neural network-based AI technologies in hemorrhage detection and treatment. The simulated injury and treatment scenarios used delineated possible benefits and opportunities available for using AI in pre-hospital trauma care. The greatest benefit of this technology lies in its ability to provide personalized interventions that optimize clinical outcomes under resource-limited conditions, such as in civilian or military mass-casualty events, involving moderate and severe hemorrhage

Cell-Extrinsic Defective Lymphocyte Development in Lmna-/- Mice

Background: Mutations in the LMNA gene, which encodes all A-type lamins, result in a variety of human diseases termed laminopathies. Lmna-/- mice appear normal at birth but become runted as early as 2 weeks of age and develop multiple tissue defects that mimic some aspects of human laminopathies. Lmna-/- mice also display smaller spleens and thymuses. In this study, we investigated whether altered lymphoid organ sizes are correlated with specific defects in lymphocyte development. Principal Findings: Lmna-/- mice displayed severe age-dependent defects in T and B cell development which coincided with runting. Lmna-/- bone marrow reconstituted normal T and B cell development in irradiated wild-type recipients, driving generation of functional and self-MHC restricted CD4 + and CD8 + T cells. Transplantation of Lmna-/- neonatal thymus lobes into syngeneic wild-type recipients resulted in good engraftment of thymic tissue and normal thymocyte development. Conclusions: Collectively, these data demonstrate that the severe defects in lymphocyte development that characterize Lmna-/- mice do not result directly from the loss of A-type lamin function in lymphocytes or thymic stroma. Instead, the immune defects in Lmna-/- mice likely reflect indirect damage, perhaps resulting from prolonged stress due to the striate

Blur Reduction in Ultrasonic Images Using Pseudo Three-Dimensional Wiener Filtering

The ability to quantitatively image material anomalies with ultrasonic methods is severely restricted by the axial and lateral resolution of the interrogating transducer. Axial resolution is controlled by the pulse duration of the transducer with shorter pulse durations yielding better axial resolution. Lateral resolution is controlled by the width of the interrogating beam with narrower beams providing better lateral resolutio

Precise and broad scope genome editing based on high-specificity Cas9 nickases

RNA-guided nucleases (RGNs) based on CRISPR systems permit installing short and large edits within eukaryotic genomes. However, precise genome editing is often hindered due to nuclease off-target activities and the multiple-copy character of the vast majority of chromosomal sequences. Dual nicking RGNs and high-specificity RGNs both exhibit low off-target activities. Here, we report that high-specificity Cas9 nucleases are convertible into nicking Cas9(D10A) variants whose precision is superior to that of the commonly used Cas9(D10A )nickase. Dual nicking RGNs based on a selected group of these Cas9(D10A) variants can yield gene knockouts and gene knock-ins at frequencies similar to or higher than those achieved by their conventional counterparts. Moreover, high-specificity dual nicking RGNs are capable of distinguishing highly similar sequences by 'tiptoeing' over pre-existing single base-pair polymorphisms. Finally, high-specificity RNA-guided nicking complexes generally preserve genomic integrity, as demonstrated by unbiased genome-wide high-throughput sequencing assays. Thus, in addition to substantially enlarging the Cas9 nickase toolkit, we demonstrate the feasibility in expanding the range and precision of DNA knockout and knock-in procedures. The herein introduced tools and multi-tier high-specificity genome editing strategies might be particularly beneficial whenever predictability and/or safety of genetic manipulations are paramount.Therapeutic cell differentiatio

Expanding the editable genome and CRISPR-Cas9 versatility using DNA cutting-free gene targeting based on in trans paired nicking

Genome editing typically involves recombination between donor nucleic acids and acceptor genomic sequences subjected to double-stranded DNA breaks (DSBs) made by programmable nucleases (e.g. CRISPR-Cas9). Yet, nucleases yield off-target mutations and, most pervasively, unpredictable target allele disruptions. Remarkably, to date, the untoward phenotypic consequences of disrupting allelic and non-allelic (e.g. pseudogene) sequences have received scant scrutiny and, crucially, remain to be addressed. Here, we demonstrate that gene-edited cells can lose fitness as a result of DSBs at allelic and non-allelic target sites and report that simultaneous single-stranded DNA break formation at donor and acceptor DNA by CRISPR-Cas9 nickases (in trans paired nicking) mostly overcomes such disruptive genotype-phenotype associations. Moreover, in trans paired nicking gene editing can efficiently and precisely add large DNA segments into essential and multiple-copy genomic sites. As shown herein by genotyping assays and high-throughput genome-wide sequencing of DNA translocations, this is achieved while circumventing most allelic and non-allelic mutations and chromosomal rearrangements characteristic of nuclease-dependent procedures. Our work demonstrates that in trans paired nicking retains target protein dosages in gene-edited cell populations and expands gene editing to chromosomal tracts previously not possible to modify seamlessly due to their recurrence in the genome or essentiality for cell function.Stem cells & developmental biolog