Electromagnetically Actuated Microcantilever for Chemical and Biochemical Sensing in Static Mode

AbstractIn this work, we present the method of bending and stress measurements with electromagnetically actuated cantilever in sensors application. Proposed method compensate the bending of the cantilever induced under stress. Bending can be translated into surface stress difference which is a measure of intermolecular interactions. In proposed method Lorentz force is a balancing force to restore the cantilever to its original position. Additionally Lorentz force give us possibility do drive cantilever bidirectionally. The bending of cantilevers is measured using optical beam deflection (OBD) method and useful signal is derived from the feedback loop, that maintains the cantilever in a fixed position by balancing the deflecting force and the balancing force

Sensitivity improvement to active piezoresistive AFM probes using focused ion beam processing

This paper presents a comprehensive modeling and experimental verification of active piezoresistive atomic force microscopy (AFM) cantilevers, which are the technology enabling high-resolution and high-speed surface measurements. The mechanical structure of the cantilevers integrating Wheatstone piezoresistive was modified with the use of focused ion beam (FIB) technology in order to increase the deflection sensitivity with minimal influence on structure stiness and its resonance frequency. The FIB procedure was conducted based on the finite element modeling (FEM) methods. In order to monitor the increase in deflection sensitivity, the active piezoresistive cantilever was deflected using an actuator integrated within, which ensures reliable and precise assessment of the sensor properties. The proposed procedure led to a 2.5 increase in the deflection sensitivity, which was compared with the results of the calibration routine and analytical calculations

Ozone fumigation increases the abundance of nutrients in Brassica vegetables : broccoli (Brassica oleracea var. italica) and Chinese cabbage (Brassica pekinensis)

Brassicaceae vegetables, among them broccoli and Chinese cabbage, are well recognized due to the nutritional properties. Four-week-old Chinese cabbage and broccoli seedlings were fumigated with O3 for 3 days before being transplanted into the field. The effect of O3 treatment was determined after reaching marketable quality (ca. 10 weeks). The inflorescences of O3-treated broccoli were enriched in vitamin E (α-tocopherol and γ-tocopherol), whereas Chinese cabbage heads had an increased content of anthocyanins and β-carotene. Ozone treatment did not significantly affect the productivity of both examined vegetables

Selenium and zinc biofortification of Pleurotus eryngii mycelium and fruiting bodies as a tool for controlling their biological activity

Pleurotus eryngii (DC:Fr.) Quel. is a cultivated mushroom of high culinary value and medicinal properties. Mycelium of P. eryngii is characterized by the ability of effective bio-elements absorption from growth media so it could be biofortified with trace elements with a functional activity in the human body. In this study, the ability of P. eryngii mycelia from in vitro cultures as well as fruiting bodies were investigated in terms of their effectiveness in zinc and selenium accumulation. The effect of Se and Zn biofortification on productivity, chemical compounds, and bio-elements content of P. eryngii was determined as well. To enhance Se and Zn content in P. eryngii fruiting bodies and mycelia, substrates were supplemented with sodium selenite, at a concentration of 50 mg $L^{-1}$, zinc sulfate, and zinc hydro-aspartate at a concentration of 87.2 and 100.0 mg $L^{-1}$, respectively. Mentioned Zn concentrations contained the same amount of zinc(II) ions, namely 20mg $L^{-1}$. The content of organic compounds include phenolic compounds and lovastatin, which were determined by a high-performance liquid chromatography with diode-array detector (HPLC-DAD) and reverse phase high-performance liquid chromatography (RP-HPLC) method with UV detection. The ability of P. eryngii to accumulate zinc and selenium from the culture medium was demonstrated. The degree of accumulation of zinc turned out to be di erent depending on the type of salt used. The present study also showed that conducting mycelium of P. eryngii in in vitro culture, with a higher content of zinc ions, can result in obtaining the materials with better antioxidant ability. The results of this study can be used to develop the composition of growing media, which ensures the production of biomass with the desired composition of elements

Focused ion beam-based microfabrication of boron-doped diamond single-crystal tip cantilevers for electrical and mechanical scanning probe microscopy

In this paper, the fabrication process and electromechanical properties of novel atomic force microscopy probes utilising single-crystal boron-doped diamond are presented. The developed probes integrate scanning tips made of chemical vapour deposition-grown, freestanding diamond foil. The fabrication procedure was performed using nanomanipulation techniques combined with scanning electron microscopy and focused ion beam technologies. The mechanical properties of the cantilever were monitored by the measurement of thermally induced vibration of the cantilever after every fabrication step, allowing the mass changes in range of ng to be estimated. The endurance of the developed probes was tested during hundreds of topography measurements, which corresponds to a scanning length equal to 13.6 m, performed on a test sample in contact and lateral force microscopy modes. Analysis of the roughness parameters confirmed the extremely high wear resistance of the fabricated probes. The linear current voltage response on a highly-oriented pyrolytic graphite sample was recorded

Integration of fluorescent, NV-rich nanodiamond particles with AFM cantilevers by focused ion beam for hybrid optical and micromechanical devices

In this paper, a novel fabrication technology of atomic force microscopy (AFM) probes integrating cantilever tips with an NV-rich diamond particle is presented. Nanomanipulation techniques combined with the focused electron beam-induced deposition (FEBID) procedure were applied to position the NV-rich diamond particle on an AFM cantilever tip. Ultrasonic treatment of nanodiamond suspension was applied to reduce the size of diamond particles for proper geometry and symmetry. The fabricated AFM probes were tested utilizing measurements of the electrical resistance at highly oriented pyrolytic graphite (HOPG) and compared with a standard AFM cantilever performance. The results showed novel perspectives arising from combining the functionalities of a scanning AFM with optically detected magnetic resonance (ODMR). In particular, it offers enhanced magnetometric sensitivity and the nanometric resolution

Optical Coherence Tomography (OCT) for examination of artworks

Chapter in the book: Bastidas D., Cano E. (eds) Advanced Characterization Techniques, Diagnostic Tools and Evaluation Methods in Heritage Science. Springer, Cham, 2018, pp 49-59 , doi: 10.1007/978-3-319-75316-4, Authors’version after embargo periodOptical coherence tomography is a fast, non-invasive technique of structural analysis utilising near-infrared radiation. Examples of using OCT, for obtaining cross-sectional images of objects of craftsmanship and an easel painting have been shown. Issues regarding the technique of execution and destruction phenomena were resolved non-invasively. In some cases, the secondary alterations can be identified and localised within the object’s structure which helps in authentication of the artwork

A Rare Case of a Primary Leiomyoma of the Clivus in an Immunocompetent Patient and a Review of the Literature Regarding Clival Lesions

Leiomyomas are common lesions that are usually located in the genitourinary and gastrointestinal tracts. Primary leiomyomas at the skull base are uncommon. They are composed of well-differentiated smooth muscle cells without cellular atypia. The diagnosis of a leiomyoma has to be confirmed by immunohistochemistry. The tumor tissue is immunoreactive for SMA, S100 and cytokeratin. Leiomyomas mainly occur in immunocompromised patients. Most tumor tissues are positive for EBV. The presented case is that of a 56-year-old immunocompetent woman with a tumor on the clivus. The radiological images suggested chordoma or fibrous dysplasia. Transnasal transsphenoidal surgery was performed. The tumor tissue consisted of well-differentiated smooth muscle cells with elongated nuclei. Immunohistochemistry revealed a positive reaction for desmin, SMA and h-Caldesmon and a negative reaction for S100, beta-catenin, PGR and Ki67. The leiomyoma diagnosis was subsequently established. To the best of our knowledge, the case of a primary leiomyoma on the clivus of an immunocompetent patient is the first to be described. We also extensively reviewed the literature on the immunohistopathological and radiological differential diagnosis of clival lesions