La vegetazione e gli habitat del SIC "IT4080008 Balze di Verghereto, Monte Fumaiolo, Ripa della Moia" (provincia di Forlì-Cesena)

Scopo della tesi è la realizzazione di rilievi fitosociologici nel SIC “IT4080008 Balze di Verghereto, Monte Fumaiolo, Ripa della Moia” (provincia di Forlì-Cesena). Il gruppo montuoso del Monte Fumaiolo, posto al confine tra le Vallate del Savio e del Tevere, è stato proposto nel 1995 come Sito di Importanza Comunitaria. E' un'area colonizzata già nell'antichità dall'uomo e comprende una grande estensione di pascoli montani, con rupi calcaree e rilievi comprendenti faggete, abetine artificiali, rimboschimenti e prati pascoli. Nell'ambito di una ricerca sulla distribuzione degli habitat di maggior pregio in questo sito sono stati realizzati campionamenti, basati sul metodo Braun Blanquet, nel periodo tra Lunglio e Settembre 2013. I dati raccolti sono stati successivamente elaborati tramite software Matlab versione 7.10.0.282 creando due dendrogrammi allo scopo di descrivere sia la qualità naturale del SIC, sia dal punto di vista degli habitat. Dalle informazioni raccolte è stata possibile la definizione di due tipologie di vegetazione: le formazioni forestali e gli ambienti aperti. I risultati mostrano 57 rilievi inerenti ai boschi divisi in ulteriori sottogruppi rappresentanti boschi a faggio, situazioni miste con Fagus sylvatica e Abies alba, querceti misti e rimboschimenti a Pinus nigra. I 27 rilievi degli ambienti aperti mostrano invece una predominanza di prati-pascolo e pascoli con situazioni di evoluzione ad arbusteti a Cytisus scoparius e Juniperus communis. Sono state campionate anche le vegetazioni a succulente presenti su affioramenti rocciosi. Le informazioni ottenute ed elaborate possono essere utili per studi futuri e per la creazione di una carta fitosociologica sulla base dei rilievi effettuati e della pregressa carta della vegetazione su base fisionomica (Barlotti 2013).

Charge generation, transport and recombination in organic solar cells

This thesis presents a study of the charge generation, transport, and recombination processes in organic solar cells performed with time-resolved experimental techniques. Organic solar cells based on polymers can be solution-processed on large areas and thus promise to become an inexpensive source of renewable energy. Despite significant improvements of the power conversion efficiency over the last decade, the fundamental working principles of organic solar cells are still not fully understood. It is the aim of this thesis to clarify the role of different performance limiting processes in organic solar cells and to correlate them with the molecular structure of the studied materials, i.e. poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C61 butyric acid methyl ester (PCBM). By combining time-of-flight charge transport measurements, transient absorption spectroscopy, a newly developed experimental technique called time delayed double pulse experiment and drift-diffusion simulations a comprehensive analysis of the working principles of P3HT:PCBM solar cells could be performed. It was found that the molecular structure of P3HT (i.e. the regioregularity) has a pronounced influence on the morphology of thin films of pristine P3HT and of blends of P3HT with PCBM. This morphology in turn affected the charge transport properties as well as the charge generation and recombination kinetics. Well-ordered regioregular P3HT was found to be characterized by a high charge carrier mobility, efficient charge generation and low but field-dependent (non-geminate) recombination. Importantly, the charge generation yield was found to be independent of temperature and applied electric field as opposed to the expectations of the Onsager-Braun model that is commonly applied to describe the temperature and field dependence of charge generation in organic solar cells. These properties resulted in a reasonably good power conversion efficiency. In contrast to this, amorphous regiorandom P3HT was found to show poor charge generation, transport and recombination properties that combine to a much lower power conversion efficiency.

Imaging spin-filter efficiency of W(001) and Ir(001) single crystals

Während der letzten Jahre wurde für Spinfilter-Detektoren ein wesentlicher Schritt in Richtung stark erhöhter Effizienz vollzogen. Das ist eine wichtige Voraussetzung für spinaufgelöste Messungen mit Hilfe von modernen Elektronensp ektrometern und Impulsmikroskopen. In dieser Doktorarbeit wurden bisherige Arbeiten der parallel abbildenden Technik weiterentwickelt, die darauf beruht, dass ein elektronenoptisches Bild unter Ausnutzung der k-parallel Erhaltung in der Niedrigenergie-Elektronenbeugung auch nach einer Reflektion an einer kristallinen Oberfläche erhalten bleibt. Frühere Messungen basierend auf der spekularen Reflexion an einerrnW(001) Oberfläche [Kolbe et al., 2011; Tusche et al., 2011] wurden auf einenrnviel größeren Parameterbereich erweitert und mit Ir(001) wurde ein neues System untersucht, welches eine sehr viel längere Lebensdauer der gereinigten Kristalloberfläche im UHV aufweist. Die Streuenergie- und Einfallswinkel-“Landschaft” der Spinempfindlichkeit S und der Reflektivität I/I0 von gestreuten Elektronen wurde im Bereich von 13.7 - 36.7 eV Streuenergie und 30◦ - 60◦ Streuwinkel gemessen. Die dazu neu aufgebaute Messanordnung umfasst eine spinpolarisierte GaAs Elektronenquellernund einen drehbaren Elektronendetektor (Delayline Detektor) zur ortsauflösenden Detektion der gestreuten Elektronen. Die Ergebnisse zeigen mehrere Regionen mit hoher Asymmetrie und großem Gütefaktor (figure of merit FoM), definiert als S2 · I/I0. Diese Regionen eröffnen einen Weg für eine deutliche Verbesserung der Vielkanal-Spinfiltertechnik für die Elektronenspektroskopie und Impulsmikroskopie. Im praktischen Einsatz erwies sich die Ir(001)-Einkristalloberfläche in Bezug auf längere Lebensdauer im UHV (ca. 1 Messtag), verbunden mit hoher FOM als sehr vielversprechend. Der Ir(001)-Detektor wurde in Verbindung mit einem Halbkugelanalysator bei einem zeitaufgelösten Experiment im Femtosekunden-Bereich am Freie-Elektronen-Laser FLASH bei DESY eingesetzt. Als gute Arbeitspunkte erwiesen sich 45◦ Streuwinkel und 39 eV Streuenergie, mit einer nutzbaren Energiebreite von 5 eV, sowie 10 eV Streuenergie mit einem schmaleren Profil von < 1 eV aber etwa 10× größerer Gütefunktion. Die Spinasymmetrie erreicht Werte bis 70 %, was den Einfluss von apparativen Asymmetrien deutlich reduziert. Die resultierende Messungen und Energie-Winkel-Landschaft zeigt recht gute Übereinstimmung mit der Theorie (relativistic layer-KKR SPLEED code [Braun et al., 2013; Feder et al.,rn2012])

Titanate-based paraelectric glass-ceramics for applications in GHz electronics

Das Gebiet der drahtlosen Kommunikationsanwendungen befindet sich in einem permanenten Entwicklungsprozess (Mobilfunkstandards: GSM/UMTS/LTE/5G, glo-bale Navigationssatellitensysteme (GNSS): GPS, GLONASS, Galileo, Beidou) zu immer höheren Datenraten und zunehmender Miniaturisierung, woraus ein hoher Bedarf für neue, optimierte Hochfrequenzmaterialien resultiert. Diese Entwicklung zeigt sich besonders in den letzten Jahren in der zunehmenden Entwicklung und Anzahl von Smartphones, welche verschiedene Technologien mit unterschiedlichen Arbeitsfrequenzen innerhalb eines Geräts kombinieren (data: 1G-4G, GPS, WLAN, Bluetooth). Die für zukünftige Technologien (z.B. 5G) benötigte Performance-steigerung kann durch die Verwendung von auf MIMO basierenden Antennensystemen realisiert werden (multiple-input & multiple-output, gesteuerte Kombination von mehreren Antennen) für welche auf dielectric Loading basierende Technologien als eine der vielversprechendsten Implementierungslösungen angesehen werden. rnDas Ziel dieser Arbeit war die Entwicklung einer geeigneten paraelektrischen Glaskeramik ($varepsilon_{r}$ > 20, $Qf$ > 5000 GHz, |$tau_f$| < 20 ppm/K; im GHz Frequenzbe-reich) im $mathrm{La_{2}O_{3}}$-$mathrm{TiO_{2}}$-$mathrm{SiO_{2}}$-$mathrm{B_{2}O_{3}}$-System für auf dielectric Loading basierende Mobilfunkkommunikationstechnologien als Alternative zu existierenden kommerziell genutzten Sinterkeramiken. Der Fokus lag hierbei auf der Frage, wie die makroskopi-schen dielektrischen Eigenschaften der Glaskeramik mit ihrer Mikrostruktur korreliert bzw. modifiziert werden können. Es konnte gezeigt werden, dass die dielektrischen Materialanforderungen durch das untersuchte System erfüllt werden und dass auf Glaskeramik basierende Dielektrika weitere vorteilhafte nichtelektro-nische Eigenschaften gegenüber gesinterten Keramiken besitzen, womit dielektrische Glaskeramiken durchaus als geeignete Alternative angesehen werden können. rnEin stabiles Grünglas mit minimalen Glasbildneranteil wurde entwickelt und die chemische Zusammensetzung bezüglich Entglasung und Redoxinstabilitäten optimiert. Geeignete Dotierungen für dielektrisch verlustarme $mathrm{TiO_{2}}$-haltige Glaskeramiken wurden identifiziert.rnDer Einfluss der Schmelzbedingungen auf die Keimbildung wurde untersucht und der Keramisierungsprozess auf einen maximalen Anteil der gewünschten Kristallphasen optimiert um optimale dielektrische Eigenschaften zu erhalten. Die mikroskopische Struktur der Glaskeramiken wurde analysiert und ihr Einfluss auf die makroskopischen dielektrischen Eigenschaften bestimmt. Die Hochfrequenzverlustmechanismen wurden untersucht und Antennen-Prototypenserien wurden analysiert um die Eignung von auf Glaskeramik basierenden Dielektrika für die Verwendung in dielectric Loading Anwendungen zu zeigen.

A model for radiofrequency electromagnetic field predictions at outdoor and indoor locations in the context of epidemiological research

We present a geospatial model to predict the radiofrequency electromagnetic field from fixed site transmitters for use in epidemiological exposure assessment. The proposed model extends an existing model toward the prediction of indoor exposure, that is, at the homes of potential study participants. The model is based on accurate operation parameters of all stationary transmitters of mobile communication base stations, and radio broadcast and television transmitters for an extended urban and suburban region in the Basel area (Switzerland). The model was evaluated by calculating Spearman rank correlations and weighted Cohen's kappa (kappa) statistics between the model predictions and measurements obtained at street level, in the homes of volunteers, and in front of the windows of these homes. The correlation coefficients of the numerical predictions with street level measurements were 0.64, with indoor measurements 0.66, and with window measurements 0.67. The kappa coefficients were 0.48 (95%-confidence interval: 0.35-0.61) for street level measurements, 0.44 (95%-CI: 0.32-0.57) for indoor measurements, and 0.53 (95%-CI: 0.42-0.65) for window measurements. Although the modeling of shielding effects by walls and roofs requires considerable simplifications of a complex environment, we found a comparable accuracy of the model for indoor and outdoor points.

Pro-inflammatory biomarkers during experimental gingivitis in patients with type 1 diabetes mellitus: a proof-of-concept study

To compare gingival crevicular fluid (GCF) biomarker levels and microbial distribution in plaque biofilm (SP) samples for subjects with type 1 diabetes (T1DM) versus healthy subjects without diabetes during experimental gingivitis (EG).

Development and in-vitro characterization of an implantable flow sensing transducer for hydrocephalus

An implantable transducer for monitoring the flow of Cerebrospinal fluid (CSF) for the treatment of hydrocephalus has been developed which is based on measuring the heat dissipation of a local thermal source. The transducer uses passive telemetry at 13.56 MHz for power supply and read out of the measured flow rate. The in vitro performance of the transducer has been characterized using artificial Cerebrospinal Fluid (CSF) with increased protein concentration and artificial CSF with 10\% fresh blood. After fresh blood was added to the artificial CSF a reduction of flow rate has been observed in case that the sensitive surface of the flow sensor is close to the sedimented erythrocytes. An increase of flow rate has been observed in case that the sensitive surface is in contact with the remaining plasma/artificial CSF mix above the sediment which can be explained by an asymmetric flow profile caused by the sedimentation of erythrocythes having increased viscosity compared to artificial CSF. After removal of blood from artificial CSF, no drift could be observed in the transducer measurement which could be associated to a deposition of proteins at the sensitive surface walls of the packaged flow transducer. The flow sensor specification requirement of +-10\% for a flow range between 2 ml/h and 40 ml/h. could be confirmed at test conditions of 37 degrees C.

AICAR and metformin, but not exercise, increase muscle glucose transport through AMPK-, ERK-, and PDK1-dependent activation of atypical PKC

Activators of 5'-AMP-activated protein kinase (AMPK) 5-aminoimidazole-4-carboxamide-1-beta-d-ribofuranoside (AICAR), metformin, and exercise activate atypical protein kinase C (aPKC) and ERK and stimulate glucose transport in muscle by uncertain mechanisms. Here, in cultured L6 myotubes: AICAR- and metformin-induced activation of AMPK was required for activation of aPKC and ERK; aPKC activation involved and required phosphoinositide-dependent kinase 1 (PDK1) phosphorylation of Thr410-PKC-zeta; aPKC Thr410 phosphorylation and activation also required MEK1-dependent ERK; and glucose transport effects of AICAR and metformin were inhibited by expression of dominant-negative AMPK, kinase-inactive PDK1, MEK1 inhibitors, kinase-inactive PKC-zeta, and RNA interference (RNAi)-mediated knockdown of PKC-zeta. In mice, muscle-specific aPKC (PKC-lambda) depletion by conditional gene targeting impaired AICAR-stimulated glucose disposal and stimulatory effects of both AICAR and metformin on 2-deoxyglucose/glucose uptake in muscle in vivo and AICAR stimulation of 2-[(3)H]deoxyglucose uptake in isolated extensor digitorum longus muscle; however, AMPK activation was unimpaired. In marked contrast to AICAR and metformin, treadmill exercise-induced stimulation of 2-deoxyglucose/glucose uptake was not inhibited in aPKC-knockout mice. Finally, in intact rodents, AICAR and metformin activated aPKC in muscle, but not in liver, despite activating AMPK in both tissues. The findings demonstrate that in muscle AICAR and metformin activate aPKC via sequential activation of AMPK, ERK, and PDK1 and the AMPK/ERK/PDK1/aPKC pathway is required for metformin- and AICAR-stimulated increases in glucose transport. On the other hand, although aPKC is activated by treadmill exercise, this activation is not required for exercise-induced increases in glucose transport, and therefore may be a redundant mechanism.

A study of progress of labour using intrapartum translabial ultrasound, assessing head station, direction, and angle of descent

Intrapartum translabial ultrasound (ITU) has the potential to objectively and quantitatively assess the progress of labour. The relationships between the different ITU parameters and their development during normal term labour have not been studied.

Identification of problems in functioning of people with sleep disorders in a clinical setting using the International Classification of Functioning Disability and Health (ICF) Checklist

We conducted an explorative, cross-sectional, multi-centre study in order to identify the most common problems of people with any kind of (primary) sleep disorder in a clinical setting using the International Classification of Functioning, Disability and Health (ICF) as a frame of reference. Data were collected from patients using a structured face-to-face interview of 45-60 min duration. A case record form for health professionals containing the extended ICF Checklist, sociodemographic variables and disease-specific variables was used. The study centres collected data of 99 individuals with sleep disorders. The identified categories include 48 (32%) for body functions, 13 (9%) body structures, 55 (37%) activities and participation and 32 (22%) for environmental factors. 'Sleep functions' (100%) and 'energy and drive functions', respectively, (85%) were the most severely impaired second-level categories of body functions followed by 'attention functions' (78%) and 'temperament and personality functions' (77%). With regard to the component activities and participation, patients felt most restricted in the categories of 'watching' (e.g. TV) (82%), 'recreation and leisure' (75%) and 'carrying out daily routine' (74%). Within the component environmental factors the categories 'support of immediate family', 'health services, systems and policies' and 'products or substances for personal consumption [medication]' were the most important facilitators; 'time-related changes', 'light' and 'climate' were the most important barriers. The study identified a large variety of functional problems reflecting the complexity of sleep disorders. The ICF has the potential to provide a comprehensive framework for the description of functional health in individuals with sleep disorders in a clinical setting.

Saliva/pathogen biomarker signatures and periodontal disease progression

The purpose of this study was to determine the role of saliva-derived biomarkers and periodontal pathogens during periodontal disease progression (PDP). One hundred human participants were recruited into a 12-month investigation. They were seen bi-monthly for saliva and clinical measures and bi-annually for subtraction radiography, serum and plaque biofilm assessments. Saliva and serum were analyzed with protein arrays for 14 pro-inflammatory and bone turnover markers, while qPCR was used for detection of biofilm. A hierarchical clustering algorithm was used to group study participants based on clinical, microbiological, salivary/serum biomarkers, and PDP. Eighty-three individuals completed the six-month monitoring phase, with 39 [corrected] exhibiting PDP, while 44 [corrected] demonstrated stability. Participants assembled into three clusters based on periodontal pathogens, serum and salivary biomarkers. Cluster 1 members displayed high salivary biomarkers and biofilm; 71% [corrected] of these individuals were undergoing PDP. Cluster 2 members displayed low biofilm and biomarker levels; 76% [corrected] of these individuals were stable. Cluster 3 members were not discriminated by PDP status; however, cluster stratification followed groups 1 and 2 based on thresholds of salivary biomarkers and biofilm pathogens. The association of cluster membership to PDP was highly significant (p < 0.0007). [corrected] The use of salivary and biofilm biomarkers offers potential for the identification of PDP or stability (ClinicalTrials.gov number, CT00277745).