Academic literature on the topic 'Regenerative Sampling'

This work is devoted to the problem of processing signal radio profiles with a duration of less than 1 ns. These radio profiles are obtained by registering the electrical component of the near field of electromagnetic radiation induced by the electronic unit of the device using the method of passive radio engineering diagnostics. The reasons for the occurrence of significant errors in the processing of signal radio profiles by modern methods of direct analog-to-digital conversion and parallel conversion of real time are shown, associated with a decrease in the number of effective bits, an increase in sampling irregularity and signal rise time. A method is proposed for reducing the arising errors by switching to the method of stroboscopic scale-to-time transformation using multiple repro duction (regeneration) of a complex signal section by means of the previously presented regenerative system. Numerical modeling of the functioning of the regeneration system together with a stroboscopic time-scale converter was carried out in the study of the area of interest in the signal radio profile in the Simulink environment of the MatLab package. Using the correlation analysis of the reconstructed and the original signal radio profile, the validity of the use of the regenerative system in the processing and recovery of signal radio profiles of subnanosecond duration is shown. An experiment was prepared and carried out using modern high-speed equipment: a real-time oscilloscope and a stroboscopic oscilloscope with a subpicosecond sampling to study the correctness of the applicability of the regeneration method when combining the scale-time transformation and real-time transformation. The result of the stroboscopic scale-to-time transformation in the equivalent time mode with the transfer of the section to the general signal reconstructed in real time is presented. It is concluded that the accuracy of processing the original signal is increased by means of regeneration followed by restoration by methods of stroboscopic scale-time transformation, which allows further analysis of the signal radio profile with the smallest errors. Also, the regeneration system together with the strobe-frame-sampler can be used as a hardware method for conducting passive radiosensor technical diagnostics.

Abstract For ultra-high speed communication systems at high center frequencies above 100 GHz, we propose a disruptive change in system architecture to address major issues regarding amplifier chains with a large number of amplifier stages. They cause a high noise figure and high power consumption when operating close to the frequency limits of the underlying semiconductor technologies. Instead of scaling a classic homodyne transceiver system, we employ repeated amplification in single-stage amplifiers through positive feedback as well as synthesizer-free self-mixing demodulation at the receiver to simplify the system architecture notably. Since the amplitude and phase information for the emerging oscillation is defined by the input signal and the oscillator is only turned on for a very short time, it can be left unstabilized and thus come without a PLL. As soon as gain is no longer the most prominent issue, relaxed requirements for all the other major components allow reconsidering their implementation concepts to achieve further improvements compared to classic systems. This paper provides the first comprehensive overview of all major design aspects that need to be addressed upon realizing a SPARS-based transceiver. At system level, we show how to achieve high data rates and a noise performance comparable to classic systems, backed by scaled demonstrator experiments. Regarding the transmitter, design considerations for efficient quadrature modulation are discussed. For the frontend components that replace PA and LNA amplifier chains, implementation techniques for regenerative sampling circuits based on super-regenerative oscillators are presented. Finally, an analog-to-digital converter with outstanding performance and complete interfaces both to the analog baseband as well as to the digital side completes the set of building blocks for efficient ultra-high speed communication.

The development of regenerative medicine is to improve existing and to search for new tools for morphological and functional tissue repair, among which plasma or fi brin enriched with platelets (PRP and PRF) can be signifi cant. Autogenic platelet masses stimulate collagen synthesis, induce vascular growth, reduce pain, provide hemostasis, accelerate regeneration, reduce the risk of postoperative infectious and infl ammatory complications, and also have powerful osteoinductive properties. Due to the ability to produce the majority of growth factors, platelets can aff ect all stages of the infl ammatory-regenerative process, and therefore their biological products are of great importance in solving the problems of regenerative medicine. The technologies for obtaining PRP and PRF are based on centrifugation of blood, as a result of which its active components are concentrated in certain areas of the centrifuge. Blood sampling with or without an anticoagulant, as well as modifi cation of centrifugation protocols, allows to obtain various forms of platelet masses, such as a liquid, gel or clots. They are classifi ed, depending on the cellular content and architecture of fi brin, into several categories, namely: pure plasma enriched in platelets (P-PRP), plasma enriched in leukocytes and platelets (L-PRP); injectable fi brin enriched with platelets (i-PRF) and pure fi brin enriched with platelets (P-PRF), as well as fi brin enriched with white blood cells and platelets (L-PRF). The main diff erence in the manufacture of PRP compared to PRF is the use of anticoagulants and activators, as well as the possibility of using two-stage centrifugation. Platelet mass is used as an independent component mainly to stimulate the restoration of muscle tissue, to heal chronic wounds, to treat articular pathologies, and in combination with other materials, in particular to replace bone defects. The mechanisms of infl uence of each of the categories of platelet mass on tissue regeneration remains poorly understood. It is necessary to standardize the protocols for their preparation, taking into account the infl uence of additional substances, such as platelet activators or blood clotting and anticoagulants, as well as optimization of the methods for using each of the platelet mass forms. Key words: platelets, PRP, PRF, centrifuges, centrifugal force.

For ultra-high speed communication systems at high center frequencies above 100 GHz, we propose a disruptive change in system architecture to address major issues regarding amplifier chains with a large number of amplifier stages. They cause a high noise figure and high power consumption when operating close to the frequency limits of the underlying semiconductor technologies. Instead of scaling a classic homodyne transceiver system, we employ repeated amplification in single-stage amplifiers through positive feedback as well as synthesizer-free self-mixing demodulation at the receiver to simplify the system architecture notably. Since the amplitude and phase information for the emerging oscillation is defined by the input signal and the oscillator is only turned on for a very short time, it can be left unstabilized and thus come without a PLL. As soon as gain is no longer the most prominent issue, relaxed requirements for all the other major components allow reconsidering their implementation concepts to achieve further improvements compared to classic systems. This paper provides the first comprehensive overview of all major design aspects that need to be addressed upon realizing a SPARS-based transceiver. At system level, we show how to achieve high data rates and a noise performance comparable to classic systems, backed by scaled demonstrator experiments. Regarding the transmitter, design considerations for efficient quadrature modulation are discussed. For the frontend components that replace PA and LNA amplifier chains, implementation techniques for regenerative sampling circuits based on super-regenerative oscillators are presented. Finally, an analog-to-digital converter with outstanding performance and complete interfaces both to the analog baseband as well as to the digital side completes the set of building blocks for efficient ultra-high speed communication.

The different strategies of tissue engineering for functional reconstruction of critical-size bone defects require a thorough knowledge of physiological mechanisms of bone repair. Bone healing is a complex process affected by various mediators. Several investigations have studied the gene expression 1 to 3 days after an acute or experimental fracture. Little is known about the humoral and cellular in vivo reaction in the early stages of bone healing. In contrast to other methods of molecule sampling and detection, which usually lead to the inhibition of the biological activity following complex sample preparation and quantification, microdialysis is a real-time monitoring technique which can be applied in living tissues providing a strong link between analytical methodology and biochemistry. In this study, the optimal conditions for microdialysis in a critical size rat long bone defect model for both in vivo and in vitro analyses were developed. Mediators and components of the extracellular matrix occurring in the first 24 to 48 hours of bone healing locally and systemically were monitored via microdialysis and blood sampling, respectively. Furthermore, novel proteins and their modulation were explored during this time frame. In vitro microdialysis was used to optimize the condition for protein recovery. Addition of bovine serum albumin (BSA) resulted in an enhanced recovery of interleukin (IL)-6. The maximal relative recovery (RR) was from 15.0% without BSA and 23.6% with BSA, while the maximal RR of transforming growth factor (TGF)-β1 was 11.2% with BSA and the concentration of TGF-β1 was below the detection limit of enzyme-linked immunosorbent assay (ELISA) without BSA. Using in vivo microdialysis, total protein concentrations varied between 0.20±0.12 mg/mL and 0.44±0.18 mg/mL. Among the mediators produced in the fracture hematoma within 24 h after the injury, IL-6 was secreted with the highest concentration of 309.1 pg/mL between 12 and 15 h after creation of the critical size bone defect. Meanwhile, the detectable concentrations of TGF-β1 in microdialysates ranged from 3.6 to 44.0 pg/mL and in blood plasma TGF-β1 was constantly producted ranging from 656.3 to 8398.2 pg/mL for 24 h after bone defct. Moreover, another constant producted growth factor in blood plasma was PDGF-BB and the concentration ranged from 222.1 to 589.4 pg/mL for 8 h after bone defect. Using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), 36 proteins were identified in the microdialysates over 8 h, and 884 proteins were identified on probes which were implanted into the bone defect over 24 h. Among the proteins identified in the hematoma, only a minority originated from the extracellular space. Protein analysis indicated five pathways associated with bone healing that were overrepresented after creating soft tissue and bone defects, of which FGF signaling was specific for bone defects. Furthermore, C-X-C motif ligands CXCL-1, CXCL-2, CXCL-3, CXCL-4, CXCL-5, CXCL-7, rodent bone protein (RoBo-1), insulin-like growth factor (IGF)-I, and chitinase-3-like protein 1 were detected in the fracture hematoma. These proteins are potentially associated to early bone healing. As seen by histological analysis, polymorphonuclear leukocytes (PMNs) and lymphocytes penetrated into the fracture hematoma immediately after surgery and peaked at 24 h. This study for the first time presents data from both the local and systemic acute response to bone and soft tissue injury in a small animal model. The results of mcrodialysis sampling may serve as a baseline for future investigations on different models and time frames. Several proteins and pathways have been identifeid as potentially important for early bone regeneration warranting in depth analysis in further studies
Zur Entwicklung neuer Strategien der Geweberegenerierung in kritischen Knochendefekten, die sich durch Selbstheilungsprozesse nicht schließen, ist das Verständnis der beteiligten physiologischen Prozesse essentiell. Der Wiederaufbau von Gewebe, wie etwa während Knochenheilungsprozesse ist komplex reguliert und erfordert das koordinierte Zusammenspiel einer Vielzahl von Zellen und Mediatoren. Obwohl bereits in zahlreichen Studien die Veränderungen in der Genexpression in den ersten 3 Tagen nach einer akuten oder experimentell induzierten Fraktur untersucht wurden, ist noch immer wenig über die zellulären und humoralen Vorgänge in den frühen Phasen der Knochenheilung in vivo bekannt. Gebräuchliche Analysemethoden erfordern komplexe Verfahren zur Probenentnahme und Nachweisreaktionen währenddessen die biologische Aktivität der untersuchten Mediatoren häufig graduell verloren geht. Die Mikrodialyse hingegen kann in Echtzeit am lebenden Objekt und am Ort der Verletzung durchgeführt werden und bildet somit eine erfolgsversprechende Plattform um die Probengewinnung noch enger mit der anschließenden biochemischen Nachweistechnik zu verbinden. Im Rahmen dieser Arbeit wurden die optimalen Konditionen zur Mikrodialyse erstmals an einem kritischen Defektmodell eines Ratten-Röhrenknochens zur in vivo und in vitro Applikation ermittelt. Dazu wurde das Vorkommen verschiedener Komponenten der extrazellulären Matrix und ausgewählter Mediatoren während der ersten 24 bis 48 Stunden der Knochenheilung überwacht. Neben der durch Mikrodialyse gewonnenen Proben wurden auch Blutproben verarbeitet um sowohl die lokale, als auch systemische Konzentration der untersuchten Proteine zu erfassen. Durch eine Proteomanalyse konnten zudem bislang in diesem Prozess unbekannte Moleküle identifiziert und verfolgt werden. Zur Optimierung der Mikrodialyse wurden zunächst die Bedingungen hinsichtlich der Proteinrückgewinnung verbessert. Durch den Zusatz von Rinderserumalbumin (BSA) konnte die Rückgewinnung von Interleukin (IL)-6 erhöht werden. Die maximale relative Rückgewinnung (RR) konnte von 15.0% ohne BSA auf 23.6% mit BSA gesteigert werden. Noch dramatischer war dieser Effekt für den transforming growth factor (TGF)-β1 von dessen eingesetzter Menge in vitro 11.2% detektiert werden konnte, während in der BSA-freien Dialyselösung kein TGF-β1 nachgewiesen wurde. Die RR blieb stets unter der Detektionsgrenze des verwendeten enzyme-linked immunosorbent assay (ELISA). In vivo-Dialysate enthielten totale Proteinkonzentrationen zwischen 0,20±0,12 mg/mL und 0,44±0,18 mg/mL. Von den innerhalb von 24 h nach Verletzung im Frakturhämatom produzierten Mediatoren wurde IL-6 am stärksten exprimiert. Die höchsten Konzentrationen (309,1pg/mL) konnten hierfür nach 12 bis 15 Stunden nach Einführung des Defekts gemessen werden. Die Konzentrationslevel von TGF-β1 hingegegen betrug nur 3,6 bis 44,0 pg/mL.Mittels high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), konnten 36 Proteine in den über 8 Stunden gewonnenen Mikrodialysaten, und 884 Proteine von Explantaten, die 24 h im Knochendefekt integriert waren, identifiziert werden. Von den im Frakturhämatom identifizierten Proteinen war nur eine Minderheit extrazellulären Ursprungs. Durch die Proteomanalyse konnten fünf Signalwegskaskaden identifiziert werden. Von diesen trat „FGF (fibroblast growth factor) signaling“ ausschließlich in Knochendefekten, nicht jedoch in den zur Kontrolle mitgeführten reinen Weichgewebedefekten auf. Im Frakturhämatom konnten die, C-X-C motif-Liganden CXCL-1, CXCL-2,CXCL-3, CXCL-4, CXCL-5, CXCL-7, rodent bone protein (RoBo-1), insulin-like growth factor (IGF)-I, und das chitinase-3-like protein 1 nachgewiesen werden. Die identifizierten Proteine könnten von Bedeutung für die Steuerung früher Knochenheilungsprozesse sein. Histologische Untersuchungen zeigten, dass polymorphkernige Leukozyten (PMNs) und Lymphozyten sofort nach der Operation in das Frakturhämatom einwandern und ihre Anzahl nach etwa 24 h ihr Maximum erreicht. Diese Studie präsentiert erstmals Daten der lokal und systemisch ablaufenden zellulären und humoralen Vorgänge als Antwort auf einen Weichgewebs-bzw. Knochendefekt in einem Nagetier-Kleintiermodell. Die Mikrodialyse-Resultate stellen eine vielversprechende Grundlage für zukünftige Untersuchungen in anderen Modellen dar. Außerdem bilden die hier identifizierten Proteine und Signalwege eine Gruppe potenter Kandidaten für weiterführende Untersuchungen zur Knochenregeration

Les formats de modulation bidimensionnels (i.e. basés sur l’amplitude et la phase de l’onde porteuse) ont gagné depuis peu le domaine des transmissions par fibre optique grâce aux progrès conjoints de l’électronique rapide et du traitement du signal, indispensables pour réaliser les récepteurs opto-électroniques utilisant la détection cohérente des signaux optiques. Pour pallier les limites actuelles en rapidité de commutation des circuits intégrés électroniques, une voie de recherche a été ouverte il y a quelques années, consistant à utiliser des technologies optiques pour faciliter la parallélisation du traitement du signal, notamment dans l’étape d’échantillonnage ultra-rapide du signal rendu possible par des horloges optiques très performantes. Le thème principal de cette thèse concerne l’étude théorique et expérimentale de la fonction de conversion analogique-numérique (ADC) de signaux optiques par un récepteur opto-électronique cohérent, associant les étapes d’échantillonnage optique linéaire, de conversion analogique-numérique et de traitement du signal. Un prototype, utilisant une solution originale pour la source d’échantillonnage, est modélisé, réalisé et caractérisé, permettant la reconstruction temporelle de signaux optiques modulés selon divers formats : NRZ, QPSK, 16-QAM. Les limitations optiques et électroniques du système sont analysées, notamment l’impact sur la reconstruction des signaux de divers paramètres : le taux d’extinction de la source optique, les paramètres de l’ADC (bande passante BW, temps d’intégration et nombre effectif de bits ENOB). Par ailleurs, de nouveaux algorithmes de traitement du signal sont proposés dans le cadre de la transmission optique cohérente à haut débit utilisant des formats de modulation bidimensionnels (amplitude et phase) : deux solutions sont proposées pour la compensation du déséquilibre de quadrature IQ dans les transmissions mono-porteuses: une méthode originale de l’estimation du maximum du rapport signal sur bruit ainsi qu’une nouvelle structure de compensation et d’égalisation conjointes; ces deux méthodes sont validées expérimentalement et numériquement avec un signal 16-QAM. Par ailleurs, une solution améliorée de récupération de porteuse (décalage de fréquence et estimation de la phase), basée sur une décomposition harmonique circulaire de la fonction de maximum de vraisemblance logarithmique, est validée numériquement pour la première fois dans le contexte des transmissions optiques (jusqu’à une modulation de 128-QAM). Enfin les outils développés dans ce travail ont finalement permis la démonstration d’une transmission sur 100 km d’un signal QPSK à 10 Gbaud fortement limité par un bruit de phase non linéaire et régénéré optiquement à l’aide d’un limiteur de puissance préservant la phase basé sur une nanocavité de cristal photonique
Bi-dimensional modulation formats based on amplitude and phase signal modulation, are now commonly used in optical communications thanks to breakthroughs in the field of electronic and digital signal processing (DSP) required in coherent optical receivers. Photonic solutions could compensate for nowadays limitations of electrical circuits bandwidth by facilitating the signal processing parallelization. Photonic is particularly interesting for signal sampling thanks to available stable optical clocks. The heart of the present work concerns analog-to-digital conversion (ADC) as a key element in coherent detection. A prototype of linear optical sampling using an original solution for the optical sampling source, is built and validated with the successful equivalent time reconstruction of NRZ, QPSK and 16-QAM signals. Some optical and electrical limitations of the system are experimentally and numerically analyzed, notably the extinction ratio of the optical source or the ADC parameters (bandwidth, integration time, effective number of bits ENOB). Moreover, some new DSPs tools are developed for optical transmission using bi-dimensional modulation formats (amplitude and phase). Two solutions are proposed for IQ quadrature imbalance compensation in single carrier optical coherent transmission: an original method of maximum signal-to-noise ratio estimation (MSEM) and a new structure for joint compensation and equalization; these methods are experimentally and numerically validated with 16-QAM signals. Moreover, an improved solution for carrier recovery (frequency offset and phase estimation) based on a circular harmonic expansion of a maximum loglikelihood function is studied for the first time in the context of optical telecommunications. This solution which can operate with any kind of bi-dimensional modulation format signal is numerically validated up to 128-QAM. All the DSP tools developed in this work are finally used in a demonstration of a 10 Gbaud QPSK 100 km transmission experiment, featuring a strong non-linear phase noise limitation and regenerated using a phase preserving and power limiting function based on a photonic crystal nanocavity

The different strategies of tissue engineering for functional reconstruction of critical-size bone defects require a thorough knowledge of physiological mechanisms of bone repair. Bone healing is a complex process affected by various mediators. Several investigations have studied the gene expression 1 to 3 days after an acute or experimental fracture. Little is known about the humoral and cellular in vivo reaction in the early stages of bone healing. In contrast to other methods of molecule sampling and detection, which usually lead to the inhibition of the biological activity following complex sample preparation and quantification, microdialysis is a real-time monitoring technique which can be applied in living tissues providing a strong link between analytical methodology and biochemistry. In this study, the optimal conditions for microdialysis in a critical size rat long bone defect model for both in vivo and in vitro analyses were developed. Mediators and components of the extracellular matrix occurring in the first 24 to 48 hours of bone healing locally and systemically were monitored via microdialysis and blood sampling, respectively. Furthermore, novel proteins and their modulation were explored during this time frame. In vitro microdialysis was used to optimize the condition for protein recovery. Addition of bovine serum albumin (BSA) resulted in an enhanced recovery of interleukin (IL)-6. The maximal relative recovery (RR) was from 15.0% without BSA and 23.6% with BSA, while the maximal RR of transforming growth factor (TGF)-β1 was 11.2% with BSA and the concentration of TGF-β1 was below the detection limit of enzyme-linked immunosorbent assay (ELISA) without BSA. Using in vivo microdialysis, total protein concentrations varied between 0.20±0.12 mg/mL and 0.44±0.18 mg/mL. Among the mediators produced in the fracture hematoma within 24 h after the injury, IL-6 was secreted with the highest concentration of 309.1 pg/mL between 12 and 15 h after creation of the critical size bone defect. Meanwhile, the detectable concentrations of TGF-β1 in microdialysates ranged from 3.6 to 44.0 pg/mL and in blood plasma TGF-β1 was constantly producted ranging from 656.3 to 8398.2 pg/mL for 24 h after bone defct. Moreover, another constant producted growth factor in blood plasma was PDGF-BB and the concentration ranged from 222.1 to 589.4 pg/mL for 8 h after bone defect. Using high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), 36 proteins were identified in the microdialysates over 8 h, and 884 proteins were identified on probes which were implanted into the bone defect over 24 h. Among the proteins identified in the hematoma, only a minority originated from the extracellular space. Protein analysis indicated five pathways associated with bone healing that were overrepresented after creating soft tissue and bone defects, of which FGF signaling was specific for bone defects. Furthermore, C-X-C motif ligands CXCL-1, CXCL-2, CXCL-3, CXCL-4, CXCL-5, CXCL-7, rodent bone protein (RoBo-1), insulin-like growth factor (IGF)-I, and chitinase-3-like protein 1 were detected in the fracture hematoma. These proteins are potentially associated to early bone healing. As seen by histological analysis, polymorphonuclear leukocytes (PMNs) and lymphocytes penetrated into the fracture hematoma immediately after surgery and peaked at 24 h. This study for the first time presents data from both the local and systemic acute response to bone and soft tissue injury in a small animal model. The results of mcrodialysis sampling may serve as a baseline for future investigations on different models and time frames. Several proteins and pathways have been identifeid as potentially important for early bone regeneration warranting in depth analysis in further studies.:I. Table of content II. List of abbreviations 1 Summary 2 Introduction 2.1 The process of bone healing 2.1.1 Stages of fracture healing 2.1.2 Early stage of inflammation 2.2 Clinical challenges 2.3 Microdialysis 2.3.1 The principle of Microdialysis 2.3.2 Parameters influencing the recovery 2.4 Aim of this study 3 Materials 3.1 Materials, devices and animals 3.2 Chemicals 3.3 Buffers and solutions 4 Methods 4.1 Background 4.2 In vitro microdialysis 4.2.1 Preparation of the protein solution 4.2.2 Microdialysis sampling procedure 4.3 In vivo microdialysis 4.3.1 Surgical procedure 4.3.2 Sample collection 4.4 Plasma samples 4.5 Determination of the fluid recovery 4.6 Determination of the relative recovery 4.7 Total protein measurement 4.8 Cytokine and growth factor analysis 4.8.1 IL-1β, IL-6, TNF-α and PDGF-BB ELISA 4.8.2 VEGF ELISA 4.8.3 TGF-β1 ELISA 4.8.4 BMP-2 ELISA 4.8.5 Proteome profilerTM array 4.9 Proteomic analysis 4.10 Histological analysis 4.11 Statistical analysis 5 Results 5.1 Protein selection 5.2 Determination of fluid recovery in vitro and in vivo 5.3 Determination of relative recovery (RR) in vitro 5.4 Determination of total protein concentration in vivo 5.5 Determination of cytokine and growth factor concentration in the microdialysate in vivo 5.5.1 IL-6 concentration 5.5.2 TGF-β1 concentration 5.5.3 IL-1β concentration 5.5.4 TNF-α concentration 5.5.5 PDGF-BB, BMP-2 and VEGF concentration 5.6 Determination of further cytokines and chemokines in the microdialysate in vivo 5.7 Protein determination using HPLC-MS/MS analysis 5.7.1 Proteins in the microdialysate 5.7.2 Proteins on the surface of the probe 5.8 Protein annotation 5.9 Determination of cytokines and growth factors in the blood plasma 5.9.1 Determination of IL-6 in the blood plasma 5.9.2 Determination of TGF-β1 in the blood plasma 5.9.3 Determination of PDGF-BB in the blood plasma 5.10 Histological analysis of the hematoma 6 Discussion 6.1 Fluid recovery 6.2 Influence of the crystalloid perfusate on relative recovery 6.3 Relative recovery of cytokines and growth factors in vitro 6.4 In vivo microdialysis 6.4.1 Total protein concentration 6.4.2 Annotation of proteins in hematoma identified by HPLC-MS/MS 6.4.3 Identification of cytokines and bone related proteins 6.5 The humoral inflammatory response 6.6 Cellular response 7 Conclusions 8 References 9 Appendix 9.1 Figure index 9.2 Table index III. Eidesstattliche Erklärung IV. Selbständigkeitserklärung V. Acknowledgements
Zur Entwicklung neuer Strategien der Geweberegenerierung in kritischen Knochendefekten, die sich durch Selbstheilungsprozesse nicht schließen, ist das Verständnis der beteiligten physiologischen Prozesse essentiell. Der Wiederaufbau von Gewebe, wie etwa während Knochenheilungsprozesse ist komplex reguliert und erfordert das koordinierte Zusammenspiel einer Vielzahl von Zellen und Mediatoren. Obwohl bereits in zahlreichen Studien die Veränderungen in der Genexpression in den ersten 3 Tagen nach einer akuten oder experimentell induzierten Fraktur untersucht wurden, ist noch immer wenig über die zellulären und humoralen Vorgänge in den frühen Phasen der Knochenheilung in vivo bekannt. Gebräuchliche Analysemethoden erfordern komplexe Verfahren zur Probenentnahme und Nachweisreaktionen währenddessen die biologische Aktivität der untersuchten Mediatoren häufig graduell verloren geht. Die Mikrodialyse hingegen kann in Echtzeit am lebenden Objekt und am Ort der Verletzung durchgeführt werden und bildet somit eine erfolgsversprechende Plattform um die Probengewinnung noch enger mit der anschließenden biochemischen Nachweistechnik zu verbinden. Im Rahmen dieser Arbeit wurden die optimalen Konditionen zur Mikrodialyse erstmals an einem kritischen Defektmodell eines Ratten-Röhrenknochens zur in vivo und in vitro Applikation ermittelt. Dazu wurde das Vorkommen verschiedener Komponenten der extrazellulären Matrix und ausgewählter Mediatoren während der ersten 24 bis 48 Stunden der Knochenheilung überwacht. Neben der durch Mikrodialyse gewonnenen Proben wurden auch Blutproben verarbeitet um sowohl die lokale, als auch systemische Konzentration der untersuchten Proteine zu erfassen. Durch eine Proteomanalyse konnten zudem bislang in diesem Prozess unbekannte Moleküle identifiziert und verfolgt werden. Zur Optimierung der Mikrodialyse wurden zunächst die Bedingungen hinsichtlich der Proteinrückgewinnung verbessert. Durch den Zusatz von Rinderserumalbumin (BSA) konnte die Rückgewinnung von Interleukin (IL)-6 erhöht werden. Die maximale relative Rückgewinnung (RR) konnte von 15.0% ohne BSA auf 23.6% mit BSA gesteigert werden. Noch dramatischer war dieser Effekt für den transforming growth factor (TGF)-β1 von dessen eingesetzter Menge in vitro 11.2% detektiert werden konnte, während in der BSA-freien Dialyselösung kein TGF-β1 nachgewiesen wurde. Die RR blieb stets unter der Detektionsgrenze des verwendeten enzyme-linked immunosorbent assay (ELISA). In vivo-Dialysate enthielten totale Proteinkonzentrationen zwischen 0,20±0,12 mg/mL und 0,44±0,18 mg/mL. Von den innerhalb von 24 h nach Verletzung im Frakturhämatom produzierten Mediatoren wurde IL-6 am stärksten exprimiert. Die höchsten Konzentrationen (309,1pg/mL) konnten hierfür nach 12 bis 15 Stunden nach Einführung des Defekts gemessen werden. Die Konzentrationslevel von TGF-β1 hingegegen betrug nur 3,6 bis 44,0 pg/mL.Mittels high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), konnten 36 Proteine in den über 8 Stunden gewonnenen Mikrodialysaten, und 884 Proteine von Explantaten, die 24 h im Knochendefekt integriert waren, identifiziert werden. Von den im Frakturhämatom identifizierten Proteinen war nur eine Minderheit extrazellulären Ursprungs. Durch die Proteomanalyse konnten fünf Signalwegskaskaden identifiziert werden. Von diesen trat „FGF (fibroblast growth factor) signaling“ ausschließlich in Knochendefekten, nicht jedoch in den zur Kontrolle mitgeführten reinen Weichgewebedefekten auf. Im Frakturhämatom konnten die, C-X-C motif-Liganden CXCL-1, CXCL-2,CXCL-3, CXCL-4, CXCL-5, CXCL-7, rodent bone protein (RoBo-1), insulin-like growth factor (IGF)-I, und das chitinase-3-like protein 1 nachgewiesen werden. Die identifizierten Proteine könnten von Bedeutung für die Steuerung früher Knochenheilungsprozesse sein. Histologische Untersuchungen zeigten, dass polymorphkernige Leukozyten (PMNs) und Lymphozyten sofort nach der Operation in das Frakturhämatom einwandern und ihre Anzahl nach etwa 24 h ihr Maximum erreicht. Diese Studie präsentiert erstmals Daten der lokal und systemisch ablaufenden zellulären und humoralen Vorgänge als Antwort auf einen Weichgewebs-bzw. Knochendefekt in einem Nagetier-Kleintiermodell. Die Mikrodialyse-Resultate stellen eine vielversprechende Grundlage für zukünftige Untersuchungen in anderen Modellen dar. Außerdem bilden die hier identifizierten Proteine und Signalwege eine Gruppe potenter Kandidaten für weiterführende Untersuchungen zur Knochenregeration.:I. Table of content II. List of abbreviations 1 Summary 2 Introduction 2.1 The process of bone healing 2.1.1 Stages of fracture healing 2.1.2 Early stage of inflammation 2.2 Clinical challenges 2.3 Microdialysis 2.3.1 The principle of Microdialysis 2.3.2 Parameters influencing the recovery 2.4 Aim of this study 3 Materials 3.1 Materials, devices and animals 3.2 Chemicals 3.3 Buffers and solutions 4 Methods 4.1 Background 4.2 In vitro microdialysis 4.2.1 Preparation of the protein solution 4.2.2 Microdialysis sampling procedure 4.3 In vivo microdialysis 4.3.1 Surgical procedure 4.3.2 Sample collection 4.4 Plasma samples 4.5 Determination of the fluid recovery 4.6 Determination of the relative recovery 4.7 Total protein measurement 4.8 Cytokine and growth factor analysis 4.8.1 IL-1β, IL-6, TNF-α and PDGF-BB ELISA 4.8.2 VEGF ELISA 4.8.3 TGF-β1 ELISA 4.8.4 BMP-2 ELISA 4.8.5 Proteome profilerTM array 4.9 Proteomic analysis 4.10 Histological analysis 4.11 Statistical analysis 5 Results 5.1 Protein selection 5.2 Determination of fluid recovery in vitro and in vivo 5.3 Determination of relative recovery (RR) in vitro 5.4 Determination of total protein concentration in vivo 5.5 Determination of cytokine and growth factor concentration in the microdialysate in vivo 5.5.1 IL-6 concentration 5.5.2 TGF-β1 concentration 5.5.3 IL-1β concentration 5.5.4 TNF-α concentration 5.5.5 PDGF-BB, BMP-2 and VEGF concentration 5.6 Determination of further cytokines and chemokines in the microdialysate in vivo 5.7 Protein determination using HPLC-MS/MS analysis 5.7.1 Proteins in the microdialysate 5.7.2 Proteins on the surface of the probe 5.8 Protein annotation 5.9 Determination of cytokines and growth factors in the blood plasma 5.9.1 Determination of IL-6 in the blood plasma 5.9.2 Determination of TGF-β1 in the blood plasma 5.9.3 Determination of PDGF-BB in the blood plasma 5.10 Histological analysis of the hematoma 6 Discussion 6.1 Fluid recovery 6.2 Influence of the crystalloid perfusate on relative recovery 6.3 Relative recovery of cytokines and growth factors in vitro 6.4 In vivo microdialysis 6.4.1 Total protein concentration 6.4.2 Annotation of proteins in hematoma identified by HPLC-MS/MS 6.4.3 Identification of cytokines and bone related proteins 6.5 The humoral inflammatory response 6.6 Cellular response 7 Conclusions 8 References 9 Appendix 9.1 Figure index 9.2 Table index III. Eidesstattliche Erklärung IV. Selbständigkeitserklärung V. Acknowledgements

AbstractThe ability to regenerate lost body parts is irregularly distributed among animals, with substantial differences in regenerative potential between and within metazoan phyla. It is widely believed that regenerative animal clades inherited some aspects of their capacity to regenerate from their common ancestors but have also evolved new mechanisms that are not shared with other regenerative animals. Therefore, to gain a broad understanding of animal regenerative mechanisms and evolution, a broad sampling approach is necessary. Unfortunately, only few regenerative animals have been established as laboratory models with protocols for functional gene studies. Here, we describe the methods to establish transgenic individuals of the marine cnidarian Hydractinia. We also provide methods for transient gene expression manipulation without modifying the genome of the animals.

AbstractPhysarum polycephalum is a protist slime mould that exhibits a high degree of responsiveness to its environment through a complex network of tubes and cytoskeletal components that coordinate behavior across its unicellular, multinucleated body. Physarum has been used to study decision making, problem solving, and mechanosensation in aneural biological systems. The robust generative and repair capacities of Physarum also enable the study of whole-body regeneration within a relatively simple model system. Here we describe methods for growing, imaging, quantifying, and sampling Physarum that are adapted for investigating regeneration and repair.

Usual diagnostic methods of leptomeningeal metastases (LM) in CerebroSpinal fluid (CSF), lack both specificity and sensitivity. The Veridex CellSearch® technique quantifying circulating tumour cells (CTCs) in blood was adapted to detect Tumour Cells (CSFTCs) in CSF from cancer patients with LM. CSF samples from 60 patients with established or suspected breast cancer or lung cancer LM and/or melanoma were evaluated. 5 mL CSF samples were collected on CellSave® preservative and analyzed within 3 days after CSF sampling. Gold Standard cytological analysis on 1 to 10 mL CSF samples from patients with established LM allowed sometimes the detection but usually not the quantification of TCs. In established LM, EpCAM+/cytokeratin+ or CD146+/HMW-MAA+ nucleated (DAPI+) cells were observed and enumerated with precision from one to up to 10 000 cells/mL. Their morphology on digital images galleries could be discriminant between breast and lung cancer. This methodology, established on a limited volume of CSF compared to the Gold Standard and allowing delayed processing, is of great interest in the diagnosis and follow-up of cancer patients with LM. The reliability of the method also opens new fields of investigation for other biological fluids and to precise the stem cell potential of metastatic cells in CSF.

Today’s products are subject to fast changes due to market conditions, short life cycles, and technological advances. Thus, an important problem in inventory planning is how to effectively manage the inventory control in a dynamic and stochastic environment. The traditional Economic Order Quantity (EOQ) and Economic Production Quantity (EPQ) both are widely and successfully used models of inventory management. However, both models assume constant and fixed parameters over time. Unfortunately, most of these assumptions are unrealistic. In this study, we generalize the EOQ and EPQ models and study production-inventory fluid models operating in a stochastic environment. The inventory level increases or decreases according to a fluid-flow rate modulated by an n-state continuous time Markov chain (CTMC). Our main objective is to minimize the expected discounted total cost which includes ordering, purchasing, production, set up, holding, and shortage costs. Applying regenerative theory, optional sampling theorem (OST) to the multi-dimensional martingale and fluid flow techniques, we develop methods to obtain explicit formulas for these cost functionals. As such, we provide managers with a useful framework and an efficient and easy-to-implement tool to coop with different demand–supply patterns.

Quaking aspen (Populus tremuloides Michx.) is a keystone species in the western US, and typically requires high-severity disturbance (historically stand-replacing fire) to regenerate and maintain population health when coexisting with conifers. Aspen forests are declining due to fire suppression, herbivory, and drought, and restoration is a priority for many forest managers. Prescribed fire and harvest are currently the only fuel reduction treatments in practice, imposing limitations on land managers. A mechanical treatment method, called ‘roller-felling,’ has been developed to mimic stand-replacing fire by reducing fuel loading and resetting succession of late-seral stage, conifer-dominated, aspen communities. We examined the ecological impact of roller-felling by investigating factors contributing to post-treatment aspen regeneration, ultimately determining the feasibility of this method as an alternative, stand-replacing disturbance treatment. Specifically, I quantified aspen regeneration stem densities to determine if the result emulated stand-replacing fire. I also measured other metrics of treatment “success”, with additional factors influencing aspen regeneration, including the ratio of suckers to true seedling establishment, ungulate browsing pressure, and herbaceous understory diversity before and after treatment. Preliminary, single-growing season, results indicate densities exceed threshold-related objectives, while related ecological impacts remain less conclusive. A second year of sampling in this upcoming field season will allow for more definitive, short-term results on the comprehensive, ecological impact of roller-felling. This research could allow for widespread application in remote areas where logging is unfeasible and in Wildland Urban Interface areas, where prescribed fire can pose a risk to communities. Additionally, this will set groundwork for long-term monitoring of roller-felled areas, furthering understanding of aspen regeneration dynamics, and will apply to forest and fire management regionally, where goals are to reduce fire risk and maintain aspen communities across the western US.

The seed bank is directly related to forest resilience because it contributes to the greatest number of regenerants after the occurrence of disturbances. Changes in seed density, floristic composition, and life forms completely alter the successional trajectory of forest environments. These changes are directly related to land use. For example, suppression of the seed bank can occur in pastures, that experience frequent fires with increase of density of seeds and predominance of herbs are typical of highly degraded areas, such as Poaceae, Rubiaceae, Asteraceae, and Cyperaceae. Melastomataceae seedlings are an important component of the seed bank in the Amazon rainforest. On the other hand, Urticaceae has greater representation in forests that exhibit low-impact land use. Any change in seed bank functionality is bound to compromise the diversity, regeneration potential and overall maintenance of tropical forests. Therefore, it is necessary to expand studies that investigate seed banks in the Amazon rainforest. It is as important to prioritize sampling methods and pursue standardization of data presentation, as well as improve the identification of species that occur in the seed bank.

The earth’s surface supports living organisms and their environments to form the biosphere, a thin film of life around the planet. Organisms participate in interacting systems or communities, and these communities are coupled to their environments by the transfer of matter and energy and by movements of air, water, and organisms. Human activities in Monteverde and elsewhere can drastically alter forest ecosystems. Textbooks on ecosystem ecology typically include such topics as community structure and composition (including plant growth forms, vertical structure, niche space, species diversity), communities and environments (species distributions along environmental gradients, community classification, succession), production (food chains and webs, decomposition and detritus, photosynthesis), and nutrient cycling (mineral nutrition of organisms, soil development, biogeochemistry). Our understanding of tropical ecosystem ecology generally falls short of what we know of other aspects of tropical biology. There are far more studies concerning population biology, autecology, and life history of tropical organisms than nutrient cycling, productivity, and landscape ecology. This pattern is true in Monteverde and in such well-studied tropical forests as La Selva, Barro Colorado Island (BCI), and the Luquillo National Forest (Lugo and Lowe 1995, McDade et al. 1994). Logistical blocks to ecosystem research exist because collaborating teams of scientists are typically needed to tackle the multiple disciplines that ecosystem-level questions require, which demands a large infrastructure and budget. Temporal problems exist because ecosystem-level phenomena (e.g., tree mortality and forest regeneration) may involve time scales longer than the life of a single granting period or lifetime of a researcher. A strong academic base for ecosystem ecology is lacking because the pool of existing studies is too small to draw patterns and extrapolate trends. These obstacles have not often been overcome in Monteverde. No Monteverde institution has provided the infrastructure to support ecosystem research (e.g., laboratory facilities, meteorological station, technical library). Some community members have negative feelings about experimental manipulations and destructive sampling sometimes needed to answer ecosystem ecology questions. From the 1970s to the 1990s, Organization for Tropical Studies (OTS) courses were in Monteverde and in such well-studied tropical forests as La Selva, Barro Colorado Island (BCI), and the Luquillo National Forest (Lugo and Lowe 1995, McDade et al. 1994).

Natural resource management at Wilson’s Creek National Battlefield (NB) is guided by our understanding of the woodlands and prairies at the time of the Civil War battle in 1861. This report is focused on the Manley Woods unit of the park. This unit is an oak-hickory woodland in the Springfield Plain subsection of the Ozarks. Canopy closure for Missouri oak woodlands can be highly variable and ranges from 30–100% across the spectrum of savanna, open woodland, and closed woodland types. In 1861, the woodland was likely a savanna community. Changes in land use (e.g., fire exclusion) caused an increase in tree density in woodlands at Wilson’s Creek NB and across the Ozarks. Savannas and open woodlands transitioned to closed canopy woodlands over time. Park management plans include restoring the area to a savanna/open woodland structure. Prescribed fire was reintroduced to Wilson’s Creek NB in 1988 and continues as the primary mechanism for reducing the tree canopy. The Manley Woods unit of Wilson’s Creek NB has been subject to intense natural and anthropogenic disturbance events such as a tornado in 2003, timber removal in 2005, prescribed fires in 2006, 2009, and 2019, an ice storm in 2007, and periodic drought. The Heartland Inventory and Monitoring Network (hereafter, Heartland Network) installed four permanent monitoring sites within the Manley Woods area of the park in 1997. Initially, we assessed ground flora and regeneration within the sites (1998–1999). We added fuel sampling after the 2003 tornado. Although overstory sampling occurred prior to the tornado, the protocol was not yet stabilized and pre-2003 overstory data were not included in these analyses. In this report, we focus on the overstory, tree regeneration, and ground cover metrics; ground flora data will be assessed in future analyses. Heartland Network monitoring data reveal that Manley Woods has undergone substantial change in canopy cover and midstory trees since 1998. While basal area and density metrics classify Manley Woods as an open woodland, the closed canopy of the midstory and overstory reveal a plant community that is moving toward closed woodland or forest structure. The most recent fire in 2019 was patchy and mild, resulting in continued increases in fuels. Ground cover metrics indicate infrequent disturbance since leaf litter continued to increase. Management objectives to restore savanna or woodland composition and structure to the Manley Woods overstory, regeneration layer, and ground cover will require implementation of prescribed fire in the future. Repeated fires can thin midstory trees and limit less fire tolerant early seral species. Additionally, mechanical or chemical treatments to reduce undesirable tree species should be considered for woodland restoration. Decreasing canopy closure is an important and essential step toward the restoration of a functioning savanna/open woodland plant community in Manley Woods. Treatments that thin the midstory and reduce fuel loading will also benefit these plant communities. With the anticipated changing climate, maintaining an open woodland community type may also provide resilience through management for native species tolerant of increasingly warmer temperatures.

Plant community monitoring at Wilson’s Creek National Battlefield (NB) focused on the restored tallgrass prairie community. Six monitoring sites were visited four times and observations of plant species and ground cover were made. In addition to those observations, we included two environmental factors in this report—precipitation and recent fire history—to help understand the vegetation data status and trends. Precipitation data (standardized vegetation index) indicated drought conditions in 2012 and some dry periods in 2016. Although prairies are adapted to drought, we found that species richness at the site and community scales (alpha and gamma diversity) were reduced in dry years. Fire management also plays an important role in shaping the plant communities. Prescribed fire occurrence became less frequent through the monitoring period. Also, additional treatments, including herbicide and mowing, likely shaped the prairie community. Tree regeneration and nonnative plants in particular may have been affected by these techniques. The prairie plant community continues to be moderately diverse despite recent increases in tree seedlings and small saplings. Species richness varied over time and was correlated with precipitation; diversity indices (H′ and J′) were similar across monitored years. Species guilds (also known as functional groups) demonstrated differing patterns. Woody plants, long a concern at the park, were abundant and statistically similar across years. Many guilds were quite variable across the sites, but nonnative forbs declined, and nonnative grasses increased. Overstory trees and canopy cover, measured for the first time in 2020, have likely influenced the composition of one site. The composition of this site points to a shrubland-savanna community. Four of the sites tended towards shrubland rather than tallgrass prairie. The vegetation monitoring protocol experienced some changes between 2008 and 2020. A key difference was a shift from sampling twice during the field season to sampling only once in a monitoring year. An anticipated decline in species richness was observed in 2012 and 2016, but we were unable to isolate sample design as the cause. Additionally, we remedied inconsistencies in how tree regeneration was recorded by tallying seedlings and saplings in the field. Our quality assurance procedures indicated that our observer error from pseudoturnover was 20.2%, meeting our expectations. Cover class estimates agreed 73% of the time, with all disagreements within one cover class. Coordinating management actions to achieve plant community goals like structure and composition of tallgrass prairie will be critical to the survival of the prairie species at the park. Fire and nonnative plant treatments along with the reduction of woody cover including trees are needed to arrest the transition to savanna and woodland community types. Frequent prescribed fire is an integral process for this community and there is no equivalent substitute. Continued focus on management for the desired tallgrass prairie community will also provide needed habitat for imperiled pollinators such as the monarch butterfly. Best management practices for pollinators on federal lands specify that treatments (prescribed fire, mowing or haying) should not occur during the blooming season or when pollinator breeding, egg, larval or pupal stages are present.

The Heartland Inventory and Monitoring Network completed its sixth year of plant community monitoring at George Washington Carver National Monument in 2020. Plant community monitoring focused on the restored prairie community. We visited seven monitoring sites in each of the six years and collected data on plant species and ground cover. In this report we also included two environmental factors—precipitation and recent fire history—to better understand the vegetation community status and trends. Since 2000, precipitation has often been below the 30-year normal. Moreover, annual precipitation was below normal for all but one of the monitoring years. We found that the drought in 2012 stood out as possibly influencing plant guild cover. Although prairies are adapted to drought, further analyses might reveal more about the role of climate change in these vegetation communities. Fire management also plays an important role in shaping plant communities. Prescribed fire occurrence became more frequent and consistent through the period of plant monitoring. Additional treatments, including herbicide and mowing, also supported a healthy prairie. The prairie plant community continues to be moderately diverse despite recent increases in tree seedlings and small saplings. Species richness in 2012 was different than in two of the six years monitored. However, diversity indices (H′ and J′) were very similar across monitored years. Species guilds (also known as functional groups) exhibited differing patterns. Woody plants, long a concern at the monument, were statistically similar across years. In 2020, grass-like species increased, but grass species appeared to have declined below prior years. Grass cover in 2004 was statistically different (greater) than in 2008 and 2020. The reasons for this are not clear. Of particular interest to the park is the status of two sumac species (Rhus glabra and R. copallinum). These species were in decline as a result of focused management actions since 2012. However, the blackberry species (Rubus spp.) seemed to be replacing the sumac in some sites. In 2020, nonnative species richness and cover were below peak levels, demonstrating management actions have been successful in maintaining low levels. The vegetation monitoring protocol experienced some changes between 2004 and 2020. A key difference was a shift from sampling twice during the field season to sampling only once in a monitoring year. Although a decline in species richness was anticipated, that pattern was not apparent. However, the abundance of grasses may have been affected by the shift in seasonality of sampling. Additionally, we remedied inconsistencies in how tree regeneration was recorded (stem tallies in some cases and cover estimates in other cases). We converted all cover data to stem tallies and density was calculated to be consistent with the protocol. The monument has had success with coordinating fire management and invasive species management. A decrease in sumac across the prairie is evidence of this success. These actions will continue to be important for maintaining the prairie in good condition into the future.

Lincoln Boyhood National Memorial celebrates the lives of the Lincoln family including the final resting place of Abraham’s mother, Nancy Hanks Lincoln. Lincoln’s childhood in Indiana was a formative time in the life our 16th president. When the Lincoln family arrived in Indiana, the property was covered in the oak-hickory forest type. They cleared land to create their homestead and farm. Later, designers of the memorial felt that it was important to restore woodlands to the site. The woodlands would help visitors visualize the challenges the Lincoln family faced in establishing and maintaining their homestead. Some stands of woodland may have remained, but significant restoration efforts included extensive tree planting. The Heartland Inventory and Monitoring Network began monitoring the woodland in 2011 with repeat visits every four years. These monitoring efforts provide a window into the composition and structure of the wood-lands. We measure both overstory trees and the ground flora within four permanently located plots. At these permanent plots, we record each species, foliar cover estimates of ground flora, diameter at breast height of midstory and overstory trees, and tree regeneration frequency (tree seedlings and saplings). The forest species composition was relatively consistent over the three monitoring events. Climatic conditions measured by the Palmer Drought Severity Index indicated mild to wet conditions over the monitoring record. Canopy closure continued to indicate a forest structure with a closed canopy. Large trees (>45 cm DBH) comprised the greatest amount of tree basal area. Sugar maple was observed to have the greatest basal area and density of the 23 tree species observed. The oaks characteristic of the early woodlands were present, but less dominant. Although one hickory species was present, it was in very low abundance. Of the 17 tree species recorded in the regeneration layer, three species were most abundant through time: sugar maple (Acer saccharum), red bud (Cercis canadensis), and ash (Fraxinus sp.). Ash recruitment seemed to increase over prior years and maple saplings transitioned to larger size classes. Ground flora diversity was similar through time, but alpha and gamma diversity were slightly greater in 2019. Percent cover by plant guild varied through time with native woody plants and forbs having the greatest abundance. Nonnative plants were also an important part of the ground flora composition. Common periwinkle (Vinca minor) and Japanese honeysuckle (Lonicera japonica) continued to be the most abundant nonnative species, but these two species were less abundant in 2019 than 2011. Unvegetated ground cover was high (mean = 95%) and increased by 17% since 2011. Bare ground increased from less than 1% in 2011 to 9% in 2019, but other ground cover elements were similar to prior years. In 2019, we quantified observer error by double sampling two plots within three of the monitoring sites. We found total pseudoturnover to be about 29% (i.e., 29% of the species records differed between observers due to observer error). This 29% pseudoturnover rate was almost 50% greater than our goal of 20% pseudoturnover. The majority of the error was attributed to observers overlooking species. Plot frame relocation error likely contributed as well but we were unable to separate it from overlooking error with our design.

The goal of Northern Colorado Plateau Network (NCPN) riparian monitoring is to determine long-term trends in hydrologic, geomorphic, and vegetative properties of wadeable streams in the context of changes in other ecological drivers, stressors, and processes. This information is intended to provide early warning of resource degradation and determine natural variability of wadeable streams. This report summarizes NCPN monitoring of Courthouse Wash in Arches National Park (NP) from 2010 to 2019. The focus of this report is to (1) present geomorphology and vegetation data from five reaches monitored in Courthouse Wash from 2010 to 2015, and (2) examine patterns in water availability at one monitoring reach from November 2010 to December 2019. Vegetation sampling and geomorphology surveys were suspended in 2016 due to budget cuts; this report presents baseline data for future comparisons. The NCPN has five monitoring reaches located between the inflow of Sevenmile Canyon, a major tributary, and the terminus of Courthouse Wash, at the Colorado River. Two reaches (2, 5) are located in Upper Courthouse Wash, and three (1, 4, 7) in Lower Courthouse Wash. Hydrologic monitoring wells are installed only at Reach 1. During our monitoring period, which included drought years in 2012 and 2018 and a wetter-than-average period from fall 2013 to 2014, groundwater levels showed steep declines corresponding to the start of the growing season each year. Hot, dry summers and falls in 2012, 2018, and 2019 showed the deepest troughs in groundwater levels. Active monsoon years helped elevate summer and fall groundwater levels in 2013 and 2014. Continued monitoring will help us better understand the relationship of climate and water availability at this reach. A geomorphic survey was completed once for reaches 2, 4, and 7, and twice for reaches 5 and 1. Powerful floods during our monitoring period resulted in aggradation of the channel in reaches 5 and 1, which were first surveyed in March 2013. Flooding in September 2013 resulted in an average of 0.24 meters of deposition found in the channel thalweg at Reach 1 in March 2014. Storm events in May 2014 caused additional aggradation. In March 2015, an average of 0.41 meters of deposition was recorded in the channel thalweg at Reach 5, with 0.32 meters of deposition between the vegetation transect headpins compared to the 2013 data. The riparian vegetation recorded at our monitoring reaches is consistent with an open-canopy Fremont cottonwood woodland with a diverse understory. Canopy closure ranged from 29% to 52%. Measurements were sensitive enough to detect a 10% reduction in canopy closure at Reach 5 during a pest infestation in June 2013. Canopy closure subsequently rebounded at the reach by 2015. Total obligate and facultative wetland cover ranged from 7% to 26%. Fremont cottonwood seedlings, saplings, and overstory trees were present at all reaches, indicating good potential for future regeneration of the canopy structure. These data can serve as a baseline for comparison with future monitoring efforts. One area of management concern is that exotic-plant frequency and cover were relatively high in all monitoring reaches. Exotic cover ranged from 2% to 30%. High exotic cover was related to years with high cover of annual brome grasses. High cover of exotic grasses is associated with increased wildfire risk in southwestern riparian systems, which are not well-adapted to fire. Managers should be prepared for this increased risk following wet winters that promote annual brome grass cover. Beaver activity was noted throughout bedrock-constrained reaches in Courthouse Wash. Beaver activity can reduce adjacent woody riparian vegetation cover, but it also contributes to maintaining a higher water table and persistent surface water. Climate change is likely to be an increasingly significant stressor in Courthouse Wash, as hotter, drier conditions decrease water levels and increase drought stress...