Nystagmus intensity and direction in bow and lean test: an aid to diagnosis of lateral semicircular canal benign paroxysmal positional vertigo

Lobiettivo è stato valutare bed side lintensità e la direzione del nistagmo (NID) nelle due differenti posizioni del bow and lean test (BLT) per differenziare la forma geotropa dalla forma apogeotropa e determinare il lato affetto in caso di vertigine parossistica da posizionamento benigna idiopatica da litiasi a carico del canale semicircolare laterale (LSC-BPPV), prima ancora di utilizzare le classiche manovre diagnostiche. Sono stati esaminati 32 soggetti affetti da LSC-BPPV, in ognuno dei quali sono state valutate lintensità e la direzione del nistagmo nelle due posizioni del BLT. Lintensità del nistagmo consente di differenziare la forma geotropa della forma apogeotropa mentre la direzione del nistagmo consente di indentificare il lato affetto. Per le noti legge che governano la fisiopatologia del CSL, un nistagmo più intenso in flessione del capo (bow) rispetto allestensione (lean) indica un flusso ampullipeto e quindi la presenza di materiale flottante nel braccio non ampollare, tipico della forma geotropa. In tal caso, se il nistagmo in flessione (bow) è diretto a sinistra, il materiale flottante deve necessariamente occupare il braccio non ampollare del CSL sinistro; viceversa se il nistagmo in flessione è diretto a destra. Daltro canto, un nistagmo più intenso in estensione del capo (lean) rispetto alla flessione (bow) indica un flusso ampullifugo e quindi la presenza di materiale aderente alla cupola (cupololitiasi) o flottante nel braccio ampollare (canalolitiasi), tipico della forma apogeotropa. In tal caso, se il nistagmo in estensione (lean) è diretto a sinistra, il materiale flottante deve necessariamente occupare il braccio ampollare del CSL sinistro; viceversa se il nistagmo in estensione è diretto a destra. Come regola generale, in entrambe le forme la direzione del nistagmo con maggiore intensità indica il lato affetto. Il NID-BLT è risultato efficace nellidentificare la forma ed il lato affetto in ventidue soggetti su ventotto (79% del campione). In caso di LSC-BPPV, la corretta esecuzione ed interpretazione del NID-BLT fornisce un importante aiuto nello stabilire la forma (geotropa versus apogeotropa) e la sede (destra versus sinistra) nella maggior parte dei pazienti, prima ancora di utilizzare le classiche manovre diagnostiche. A differenza del test di Choung, che richiede di conoscere a priori se il paziente ha una forma geotropa o apogeotropa, il nostro test consente di formulare direttamente la diagnosi o di fornire elementi indispensabili nei casi in cui la diagnosi di lato è dubbia, mentre il paziente è ancora in posizione seduta

Materials and technological processes for High-Gradient accelerating structures: new results from mechanical tests of an innovative braze-free cavity

Pure oxygen-free high-conductivity copper is a widely used material for manufacturing accelerating cavities working at room temperature. Several studies attempted to explain limitations associated with the maximum allowed field gradients and the behaviour of vacuum RF breakdown in copper accelerating structures through generation and movement of dislocations under stresses associated with RF electric and magnetic fields. Pure copper and also copper alloys undergo mechanical and thermal treatments to be hardened and strengthened during manufacturing, although their mechanical properties significantly change after heating above 590ˆC. High temperature brazing and diffusion bonding are assembly methods widely used to manufacture ultra-high vacuum accelerating devices. However, these processes, occurring at about 800-1000ˆC, significantly affect the mechanical properties of copper and copper alloys. We present here a novel Tungsten Inert Gas welding procedure, which is fast and keeps the high-gradient surfaces of the cavity and other components well below the copper annealing temperature. This process may be successfully used to manufacture copper-based accelerating components. This technology preserves the hardness and cleanliness of copper in order to achieve the maximum accelerating gradient

Reliability of RF MEMS capacitive and ohmic switches for space redundancy configurations

In this paper RF MEMS switches in coplanar waveguide (CPW) configuration designed for redundancy space applications have been analyzed, to demonstrate their reliability in terms of microwave performances when subjected to DC actuations up to one million cycles. As a result, both the investigated structures fulfill the current electrical requirements expected for redundancy logic purposes

Review on Augmented Reality in Oral and Cranio-Maxillofacial Surgery: Toward 'Surgery-Specific' Head-Up Displays

In recent years, there has been an increasing interest towards the augmented reality as applied to the surgical field. We conducted a systematic review of literature classifying the augmented reality applications in oral and cranio-maxillofacial surgery (OCMS) in order to pave the way to future solutions that may ease the adoption of AR guidance in surgical practice. Publications containing the terms 'augmented reality' AND 'maxillofacial surgery', and the terms 'augmented reality' AND 'oral surgery' were searched in the PubMed database. Through the selected studies, we performed a preliminary breakdown according to general aspects, such as surgical subspecialty, year of publication and country of research; then, a more specific breakdown was provided according to technical features of AR-based devices, such as virtual data source, visualization processing mode, tracking mode, registration technique and AR display type. The systematic search identified 30 eligible publications. Most studies (14) were in orthognatic surgery, the minority (2) concerned traumatology, while 6 studies were in oncology and 8 in general OCMS. In 8 of 30 studies the AR systems were based on a head-mounted approach using smart glasses or headsets. In most of these cases (7), a video-see-through mode was implemented, while only 1 study described an optical-see-through mode. In the remaining 22 studies, the AR content was displayed on 2D displays (10), full-parallax 3D displays (6) and projectors (5). In 1 case the AR display type is not specified. AR applications are of increasing interest and adoption in oral and cranio-maxillofacial surgery, however, the quality of the AR experience represents the key requisite for a successful result. Widespread use of AR systems in the operating room may be encouraged by the availability of 'surgery-specific' head-mounted devices that should guarantee the accuracy required for surgical tasks and the optimal ergonomics

Molybdenum sputtering film characterization for high gradient accelerating structures

Technological advancements are strongly required to fulfill the demands of new accelerator devices with the highest accelerating gradients and operation reliability for the future colliders. To this purpose an extensive R&D regarding molybdenum coatings on copper is in progress. In this contribution we describe chemical composition, deposition quality and resistivity properties of different molybdenum coatings obtained via sputtering. The deposited films are thick metallic disorder layers with different resistivity values above and below the molibdenum dioxide reference value. Chemical and electrical properties of these sputtered coatings have been characterized by Rutherford backscattering, XANES and photoemission spectroscopy. We will also present a three cells standing wave section coated by a molybdenum layer $\sim$ 500 nm thick designed to improve the performance of X-Band accelerating systems.Comment: manuscript has been submitted and accepted by Chinese Physics C (2012

New cost-effective technologies applied to the study of the glacier melting influence on physical and biological processes in Kongsfjorden area (Svalbard)

The Arctic region is greatly affected by climate change, with evident alterations in both physical and biological processes: temperatures are changing at a rate that is twice the global average and phytoplankton productivity is directly affected by ice melting. Continuous monitoring of this ecosystem is fundamental to gain greater understanding of the impact of changes on the natural environment, but the Global Ocean Observing System only provides partial coverage in these extreme areas, which are particularly difficult to reach. Technological progress in oceanographic measurement capabilities is indispensable for the implementation of marine observatories, especially in these remote regions. In recent years, autonomous systems and cost-effective technologies have proved to be valuable for increasing spatial and temporal coverage of data. This is the case with the innovative ArLoC (Arctic Low-Cost) probe, which was designed and developed for easy integration into various types of platforms, enabling continuous measurement of temperature, pressure and fluorescence of chlorophyll a. This work reports on the results of two scientific campaigns carried out in Kongsfjorden (Svalbard Islands) in 2018 in the framework of the UVASS (Unmanned Vehicles for Autonomous Sensing and Sampling) research project. The ArLoC probe was integrated onboard the PROTEUS (Portable RObotic TEchnology for Unmanned Surveys) unmanned semi-submersible vehicle and this allowed us to collect important data in the stretches of sea near tidewater glacier fronts. The acquired data showed several significant effects of glacier melting such as: high temperature and salinity gradients, which cause considerable variations in water mass stratification, and an increase in turbidity and the chlorophyll a concentration, which directly affects primary productivity and the trophic chain. During the surveys, ArLoC proved to be an easy-to-integrate, very reliable instrument, which permitted high spatial resolution investigation of ecological processes during glacier melting as never studied before

Guselkumab for treatment of moderate-to-severe plaque psoriasis: real-life effectiveness and drug-survival for up to 148 weeks

Background: Real-world data are useful to guide the management of psoriasis. Here, we present data on the effectiveness and survival of guselkumab in moderate-to-severe chronic plaque psoriasis for up to 148 weeks. Research design and methods: Cross-sectional study of 122 patients receiving guselkumab (100 mg at weeks 0 and 4, and then every 8 weeks thereafter) for>12 weeks, from November 2018 to April 2022. Main outcome measures: Clinical features and drug survival were analyzed up to 148 weeks. Results: Obese patients (32.8%) and those receiving prior biologics (64.8%) were included. Guselkumab treatment was associated with a rapid decrease in PASI, from 16.2 to 3.2 at week 12, and long-term improvements in all subgroups (97.6%, 82.9%, and 63.4% of patients, respectively, achieved PASI 75, 90, and 100 after 148 weeks). More non-obese than obese patients achieved PASI 100 at week 148 (86.4% vs 38.9%), as did bio-naïve vs bio-experienced patients (86.7% vs 50.0%). Previous biologic therapy was a negative prognostic factor for achieving PASI 100 over the long-term by multivariate analysis (p = 0.005). Overall, 96% of patients were on treatment after 2 years. Conclusions: Real-world data confirm the long-term effectiveness of guselkumab in patients with psoriasis

Deep ice as a geochemical reactor: Insights from iron speciation and mineralogy of dust in the Talos Dome ice core (East Antarctica)

Thanks to its insolubility, mineral dust is considered a stable proxy in polar ice cores. With this study we show that the Talos Dome ice core (TALDICE, Ross Sea sector of East Antarctica) displays evident and progressive signs of post-depositional processes affecting the mineral dust record below 1000g m deep. We apply a suite of established and cutting-edge techniques to investigate the properties of dust in TALDICE, ranging from concentration and grain size to elemental composition and Fe mineralogy. Results show that through acidic/oxidative weathering, the conditions of deep ice at Talos Dome promote the dissolution of specific minerals and the englacial formation of others, affecting primitive dust features. The expulsion of acidic atmospheric species from ice grains and their concentration in localized environments is likely the main process responsible for englacial reactions. Deep ice can be seen as a "geochemical reactor"capable of fostering complex reactions which involve both soluble and insoluble impurities. Fe-bearing minerals can efficiently help in exploring such transformations

Lie point symmetries and first integrals: the Kowalevsky top

We show how the Lie group analysis method can be used in order to obtain first integrals of any system of ordinary differential equations. The method of reduction/increase of order developed by Nucci (J. Math. Phys. 37, 1772-1775 (1996)) is essential. Noether's theorem is neither necessary nor considered. The most striking example we present is the relationship between Lie group analysis and the famous first integral of the Kowalevski top.Comment: 23 page