Search results for "sers"
showing 10 items of 478 documents
Ultra-sensitive fluorescence spectroscopy of isolated surface-adsorbed molecules using an optical nanofiber.
2009
The strong radial confinement and the pronounced evanescent field of the guided light in optical nanofibers yield favorable conditions for ultra-sensitive surface spectroscopy of molecules deposited on the fiber. Using the guided mode of the nanofiber for both excitation and fluorescence collection, we present spectroscopic measurements on 3,4,9,10-perylenetetracarboxylic dianhydride molecules (PTCDA) at ambient conditions. Surface coverages as small as 1 per thousand of a compact monolayer still give rise to fluorescence spectra with a good signal to noise ratio. Moreover, we analyze and quantify the self-absorption effects due to reabsorption of the emitted fluorescence light by circumjac…
Refractive micro-optical elements for surface plasmons: from classical to gradient index optics.
2010
Controlling the propagation of surface plasmons along a metal-dielectric interface is a key feature for the development of surface plasmon based circuits. We have designed various two-dimensional refractive dielectric optical elements for surface plasmons (SP) and characterized their capacity to route SP, using near- or far-field techniques. We first present basic devices analogous to usual optical components and the associated challenges for SP optics. We then use a metamaterial approach to locally vary the refractive index and fabricate gradient index structures for SP circuitry.
Italian Potential Biogas and Biomethane Production from OFMSW
2015
This work is aimed at predicting the potential biogas and biomethane production, using the Organic Fraction of Municipal Solid Waste (OFMSW), in Italy, where 1388 Anaerobic Digestion (AD) plants (power of 7.4 TWh, equal to 640.4 ktep) are nowadays available. In order to compute the potential biogas and biomethane production in the 20 Italian regions, the data about OFMSW production in 2010-2013 period have been evaluated. The Italian production of OFMSW, that was 5.2 million tons in 2013 (18% of MSW), could be used inside bioreactors for producing biogas and digestate, that must be aerobically composted into a biofertiliser. In 2013, the Italian potential biogas production from OFMSW was 73…
The Perceived Role of Technology in Career Guidance among Practitioners Who are Experienced Internet Users
2011
The increasing use of technology is placing new demands on career guidance practitioners. This article examines what changes, if any, have occurred in the perceptions of guidance practitioners regarding their role and the role of the internet in meeting guidance goals and delivering career guidance services. The data were collected in focus groups in 2001–2002 and a follow-up study in 2010. A total of seven focus groups were held. The data were analysed using combined methods. The results indicated that practitioners now observe that the need for differentiated service delivery modes is more explicit due to varied levels of readiness in decision-making and ICT literacy.
Chronic neuropathic facial pain after intense pulsed light hair removal. Clinical features and pharmacological management
2015
Intense Pulsed Light (IPL) photodepilation is usually performed as a hair removal method. The treatment is recommended to be indicated by a physician, depending on each patient and on its characteristics. However, the use of laser devices by medical laypersons is frequent and it can suppose a risk of damage for the patients. Most side effects associated to IPL photodepilation are transient, minimal and disappear without sequelae. However, permanent side effects can occur. Some of the complications are laser related but many of them are caused by an operator error or mismanagement. In this work, we report a clinical case of a patient that developed a chronic neuropathic facial pain following…
Making and breaking relationships on social media: the impacts of brand and influencer betrayals
2021
This study considers how the relationships between social media influencers, brands and individuals are intertwined on social media and analyses the spill-over effects of feelings of betrayal. An experimental design with two transgression scenarios (influencer vs. brand) was created, and 250 individuals were recruited to participate in the study. The results show that a perceived betrayal by a brand can negatively affect the perceived coolness of the social media influencer that has endorsed the brand, as well as the parasocial relationships that followers have with the influencer. Accordingly, a perceived betrayal by a social media influencer can negatively affect attitudes, trust and purc…
Alterations in membrane and firing properties of layer 2/3 pyramidal neurons following focal laser lesions in rat visual cortex.
2013
Focal cortical injuries are well known to cause changes in function and excitability of the surviving cortical areas but the cellular correlates of these physiological alterations are not fully understood. In the present study we employed a well established ex vivo-in vitro model of focal laser lesions in the rat visual cortex and we studied membrane and firing properties of the surviving layer 2/3 pyramidal neurons. Patch-clamp recordings, performed in the first week post-injury, revealed an increased input resistance, a depolarized spike threshold as well as alterations in the firing pattern of neurons in the cortex ipsilateral to the lesion. Notably, the reported lesion-induced alteratio…
Remote estimation of blood pulse pressure via temporal tracking of reflected secondary speckles pattern
2011
We present a novel technique for remote noncontact blood pulse pressure measurement. It is based on tracking both temporal and amplitude changes of reflected secondary speckle produced in human skin when illuminated by a laser beam. The implemented technique extracts the difference between the systolic and the diastolic blood pressure. Experimental results are presented showing good agreement when compared with conventional measurement methods.
Low level 809-nm diode laser-induced in vitro stimulation of the proliferation of human gingival fibroblasts
2002
Background and Objective The authors investigated the effects of low level laser irradiation on the proliferation rate of human gingival fibroblasts (HGF) in vitro. Study Design/Materials and Methods HGF were obtained from gingival connective tissue explants and cultured under standard conditions. 110 cell cultures in their logarithmic growth phase were spread on 96-well tissue culture plates and were irradiated at energy fluences of 1.96–7.84 J/cm2. Another 110 cultures served as control. An 809-nm semiconductor laser operated at a power output of 10 mW in the cw-mode was used. The time of exposure varied between 75 and 300 seconds. Laser treatment was performed alternatively once, twice, …
Hundertvasera daiļrade kā iedvesmas avots vizuālās mākslas mācību stundās 5. klasē
2020
Darba autors: Estere Gleške Diplomdarba tēma: Hundertvasera daiļrade kā iedvesmas avots vizuālās mākslas mācību stundās 5.klasē. Darba mērķis ir atklāt mākslinieka Hundertvasera daiļradi kā ierosmes avotu radošai darbībai vizuālās mākslas stundās 5.klasē. Pirmā nodaļa iepazīstina ar mākslinieku Hundertvaseru, viņa daiļradi, ietekmes avotiem, kā arī mākslinieciskās izteiksmes līdzekļiem, kurus viņš savos darbos izmantojis. Otrajā nodaļā izpētīti un analizēti normatīvie dokumenti, pusaudžu vecumposma īpatnības un izveidota uzdevumu kopa, metodiskais materiāls 8 mācību stundām, kā arī izstrādāti vērtēšanas kritēriji un sistēma, tāpat arī pamatotas mācību procesā izmantojamās metodes. Trešā nod…