Advanced Silicon Microstructuring by Electrochemical Micromachining: Technology and Applications

Electrochemical micromachining technology, namely ECM, is a newly proposed microstructuring technique based on electrochemical etching of n-type silicon in aqueous electrolytes containing hydrofluoric acid. Among the main features of ECM there are: i) high aspect-ratio (HAR) of feasible structures, and in turn, high integration density; ii) fine control of etching anisotropy (from 0 to 1), and in turn, enhanced flexibility in fabrication; iii) reduced roughness (about 20 nm) of etched surface. This thesis is aimed at demonstrating that ECM technology can be successfully used for the fabrication of silicon (Si) based microstructures and microsystems for a wide range of applications ranging from integrated optics, to optofluidics, from biology (3D cell culture) to synthesis of nano/micro-structured conducting polymers film. As to optics applications, for the first time, we report fabrication of a novel Si-optical platform where light from standard single mode optical fiber is directly coupled in and out high order vertical silicon/air PhCs operating in the near-infrared region. The platform consists of ECM-micromachined Si-substrate integrating an array of vertical silicon/air PhCs featuring a transmission peak at λ=1.55 μm, together with U-grooves and mechanical end-stop structures for readout optical fibers thus enabling easy-to-use and plug-and-play operation mode. As to optofluidic applications, ECM-fabricated vertical HAR-PhCs were integrated into optofluidic microsystems (OFM) together with fluidic microchannels obtained by potassium hydroxide (KOH) etching. A sensitivity value of 1049 nm/RIU at 1.55 μm and limit of detection of 10-3 RIU are obtained. Moreover, we report the successful application of ECM technology to the realization of all-silicon OFMs in which HAR-PhCs are integrated by one-etching-step together with microfluidic reservoirs/channels and fiber grooves, for alignment/positioning of readout optical fibers in front of the PhC. Assessment of this OFM as refractive index sensor was also performed. High sensitivity of 670 nm/RIU at 1.55 μm and good limit of detection of about 10-3of PhC-OFMs were obtained. As to 3D cell culture applications, we have demonstrated ECM-fabrication of in vitro 3D-microincubators featuring HAR Si-microstructures for mesenchymal cells culturing. In particular, the proposed microincubator selects mesenchymal cells that show the ability to grow in the gaps between two adjacent HAR silicon walls. Finally, we have developed a novel technology for microstructuring polypyrrole (PPy) films based on light-activated PPy electrosynthesis on ECM-micromachined Si-substrates. Scanning electron microscopy highlights as light-activation allows a highly conformal polymer growth yielding a 3D-PPy structure perfectly replicating the Si microstructure

First Record of Eurasian Spoonbills Platalea leucorodia feeding on Branchiopoda in a temporary wetland

The diet of the Eurasian Spoonbill Platalea leucorodia is poorly documented with only the most common prey groups known, namely small fishes, amphibians, reptiles, crustaceans, molluscs, worms, leeches and plant material. Here, the first observations of three small crustaceans, Branchiopoda Triops cancriformis (Notostraca), Chirocephalus diaphanus (Anostraca), and Cyzicus tetracerus (Spinicaudata) are documented as prey of the Eurasian Spoonbill in a temporary wetland near the San Teodoro salt pan (Marsala, western Sicily). These observations provide a new insight into the foraging ecology of the species, showing its extreme opportunism in targeting small prey when feeding in a temporary wetland system

The Big Wish, Concordia College, 2015

The purpose of this Capstone project was to create an event centered on an existing event within the sports industry. The Big Wish - Concordia College an event based off a wish granting experience through the Make-a-Wish Foundation along with a football game at Concordia College in Moorhead, Minnesota. Further research was conducted to identify how the Make-a-Wish Foundation grants wishes to children. Some of the findings indicated that a child must be between 2.5 and years old, have a life threatening illness, referred by someone, and have not had a wish granted previously. Using the research shown through the wish granting process, the event was created and a child by the name of Jimmy Flowers was identified to have a wish be granted. Through the collaboration of the local Make-a-Wish Foundation, Concordia College, and the Student Athletic Advisory Committee at Concordia, the wish experience for Jimmy Flowers was able to be granted. This Capstone detailed the specifics of the Big Wish - Concordia College event, including items such as: a marketing and risk management plan, budget, ethical analysis, a plan for motivating employees, and a personal reflection

EVOLUZIONE DELLA LAGUNA DI TONNARELLA (MAZARA DEL VALLO, TRAPANI) E SUO ATTUALE VALORE ORNITOLOGICO

Temporal changing of Tonnarella lagoon (Mazara del Vallo, Trapani) and its current ornithological value. Aims of this work were to highlight the importance of a small and artificial recently formed wetland area, that presents different interesting ornithological peculiarities. The Tonnarella lagoon is a breeding site of Little Tern Sternula albifrons and Kentish Plover Charadrius alexandrinus, both classified as “endangered” species in 2011 by the Red List of breeding birds in Italy; the site is considered of “national importance“ for Kentish Plover and “recorded site“ for the Sandwich Tern Sterna sandvicensis, due to the consistency of its wintering populations. Besides, the ornithological importance of this zone increases by the presence of migrating species included in the “Birds” 79/409/CEE Directive and in the Bern, Bonn and Washington international conventions; their status is considered at risk in the near future, according to the most recent estimates in Europe. The value of this area has been also highlighted by the method of evaluation H.A.T., both for breeding and wintering species. Nevertheless, Tonnarella lagoon is at risk of disappearing, because of the competent Authority choices to use it as storage for the dredging of sludge extracted from the harbour of Mazara del Vallo

IL SUCCIACAPRE CAPRIMULGUS EUROPAEUS (Aves Caprimulgiformes) NIDIFICANTE ALLO STAGNONE DI MARSALA (TRAPANI)

First breeding of Nightjar Caprimulgus europaeus (Aves Caprimulgiformes) in the Stagnone di Marsala (Trapani, western Sicily

New data on Calomera panormitana panormitana (Ragusa, 1906) in Sicily (Coleoptera Cicindelidae)

Calomera panormitana panormitana (Ragusa, 1906) (Coleoptera Cicindelidae) is an endemic species of Sicily, of remarkable biogeographic and ecological importance. It belongs to a small group of species of eastern Mediterranean distribution and it is peculiar for living on the low rocky coasts, near the sea. In this paper we provide new and summarized data on the presence of this species in Sicily. We examined its habitat, ecology and phenology in detail, and we provide useful elements for a better protection. In particular, the presence of this species also in some small islands, located at a short distance from the coast, highlights the presence of important refuge areas to be protected and promoted

3. Eurasian Thick-knee Burhinus oedicnemus

Eurasian Thick-knee Burhinus oedicnemu