990 research outputs found
Topological Characterization and Advanced Noise-Filtering Techniques for Phase Unwrapping of Interferometric Data Stacks
This chapter addresses the problem of phase unwrapping interferometric data stacks, obtained by multiple SAR acquisitions over the same area on the ground, with a twofold objective. First, a rigorous gradient-based formulation for the multichannel phase unwrapping (MCh-PhU) problem is systematically established, thus capturing the intrinsic topological character of the problem. The presented mathematical formulation is consistent with the theoretical foundation of the discrete calculus. Then within the considered theoretical framework, we formally describe an innovative procedure for the noise filtering of time-redundant multichannel multilook interferograms. The strategy underlying the adopted multichannel noise filtering (MCh-NF) procedure arises from the key observation that multilook interferograms are not fully time consistent due to multilook operations independently applied on each single interferogram. Accordingly, the presented MCh-NF procedure suitably exploits the temporal mutual relationships of the interferograms. Finally, we present some experimental results on real data and show the effectiveness of our approach applied within the well-known small baseline subset (SBAS) processing chain, thus finally retrieving the relevant Earth’s surface deformation time series for geospatial phenomena analysis and understanding
Satellite SAR Interferometry for Earth’s Crust Deformation Monitoring and Geological Phenomena Analysis
Synthetic aperture radar interferometry (InSAR) and the related processing techniques provide a unique tool for the quantitative measurement of the Earth’s surface deformation associated with certain geophysical processes (such as volcanic eruptions, landslides and earthquakes), thus making possible long-term monitoring of surface deformation and analysis of relevant geodynamic phenomena. This chapter provides an application-oriented perspective on the spaceborne InSAR technology with emphasis on subsequent geophysical investigations. First, the fundamentals of radar interferometry and differential interferometry, as well as error sources, are briefly introduced. Emphasis is then placed on the realistic simulation of the underlying geophysics processes, thus offering an unfolded perspective on both analytical and numerical approaches for modeling deformation sources. Finally, various experimental investigations conducted by acquiring SAR multitemporal observations on areas subject to deformation processes of particular geological interest are presented and discussed
High prevalence of polycystic ovary syndrome in women with mild hirsutism and no other significant clinical symptoms
OBJECTIVE: To verify the conclusions of the Endocrine Society Guidelines that patients with mild hirsutism and no other important clinical signs (menstrual irregularities, infertility, central obesity, acanthosis nigricans, rapid progression of the hirsutism, clitoromegaly) should not be further studied.
DESIGN: Retrospective study in patients referred because of mild hirsutism and no other clinical signs.
SETTING: Department of Clinical Medicine of the University of Palermo.
PATIENT(S): One hundred fifty-two patients with mild hirsutism.
INTERVENTION(S): Measurement of serum testosterone, dehydroepiandrosterone sulfate, 17-OH-Progesterone, assessment of ovulation by measurement of progesterone in 21 to 24 days and ovarian ultrasound.
RESULT(S): In 72 (47%) patients a diagnosis of polycyctic ovarian syndrome (PCOS) was performed. Polycyctic ovarian syndrome patients included 56 patients with the mild ovulatory form (OV-PCOS) but also 16 patients with the anovulatory form (classic PCOS). Three (2%) patients had nonclassic adrenal hyperplasia.
CONCLUSION(S): Because of the high prevalence of PCOS and the possibility of finding nonclassic 21-hydroxylase deficiency, patients with mild hirsutism need a diagnostic evaluation that should include 17-hydroxyprogesterone measurement plus assessment of ovulation and ovarian ultrasound
Grotta della Rondinella a Polignano a Mare: un progetto di ricerca della Federazione Speleologica Pugliese
Grotta della Rondinella (PU 71) è una tra le cavità più note
e suggestive della fascia costiera di Polignano a Mare, in
provincia di Bari. Essa presenta un doppio ingresso: da
terra, attraverso uno sprofondamento (sinkhole) e da mare
con un ampio portale che conduce a una bella spiaggia
in ciottoli. Sebbene inserita in un contesto certamente ad
alta vocazione turistica, la cavità , al pari delle molte altre
distribuite lungo la costa, non è mai stata adeguatamente
tutelata, per cui è di frequente oggetto di degrado, specialmente
durante la affollata stagione estiva. Grazie ad un finanziamento
privato, è stato avviato un progetto di ricerca
multi-disciplinare della Federazione Speleologica Pugliese,
comprendente un nuovo rilievo della cavità , indagini a
carattere geologico-strutturale e di geomorfologia ipogea,
analisi petrografiche e mineralogiche, indagini geofisiche
indirizzate alla verifica di eventuali prosecuzioni degli ambienti
ipogei. Inoltre, è stato messo in opera il monitoraggio
micro-climatico della cavità , e sono stati condotti studi
di carattere biospeleologico, con particolare riguardo ai
chirotteri, presenti con una piccola colonia nella grotta.
L’insieme dei dati così raccolti costituisce indubbiamente
un’importante banca dati su un singolo ambiente ipogeo,
raramente disponibile in Puglia.Rondinella Cave (PU 71 in the Cadastre of Caves of Apulia
region, managed by the Apulian Speleological Federation)
is one of the most well known coastal karst caves
at Polignano a Mare, along the Adriatic coast in the Bari
province. The cave has a double entrance: a wide access
allows to enter by the sea, leading to a nice pebble shore,
whilst inland a collapse sinkhole represents the main
access, produced by fall of the rock diaphragm above the
cave. Even though the cave is in a coastal sector heavily
frequented by tourists, it was never adequately safeguarded,
and, as many other coastal caves in the area, commonly
experiences negative effects due to anthropogenic
disturbance.
Thanks to private funds, a research project was recently
started by the Apulian Speleological Federation: it included,
but was not limited to, the cave survey with modern
speleological techniques; geological, structural and geomorphological
analyses; petrographic and mineralogical
researches; geophysical surveys addressed to identification
of likely further cavities in the areas surrounding
the cave. In addition, a micro-climatic monitoring system
has been established, and the colony of bats hosted in the
cave has been monitored and studied. The amount of data
so collected represent without any doubt one of the widest
database nowadays available about a karst cave in Apulia
Heparan sulfates facilitate harmless amyloidogenic fibril formation interacting with elastin-like peptides
Heparan sulfates (HSs) modulate tissue elasticity in physiopathological conditions by interacting with various matrix constituents as tropoelastin and elastin-derived peptides. HSs bind also to protein moieties accelerating amyloid formation and influencing cytotoxic properties of insoluble fibrils. Interestingly, amyloidogenic polypeptides, despite their supposed pathogenic role, have been recently explored as promising bio-nanomaterials due to their unique and interesting properties. Therefore, we investigated the interactions of HSs, obtained from different sources and exhibiting various degree of sulfation, with synthetic amyloidogenic elastin-like peptides (ELPs), also looking at the effects of these interactions on cell viability and cell behavior using in vitro cultured fibroblasts, as a prototype of mesenchymal cells known to modulate the soft connective tissue environment. Results demonstrate, for the first time, that HSs, with differences depending on their sulfation pattern and chain length, interact with ELPs accelerating aggregation kinetics and amyloid-like fibril formation as well as self-association. Furthermore, these fibrils do not negatively affect fibroblasts' cell growth and parameters of redox balance, and influence cellular adhesion properties. Data provide information for a better understanding of the interactions altering the elastic component in aging and in pathologic conditions and may pave the way for the development of composite matrix-based biomaterials
A narrative review on the implementation of liquid biopsy as a diagnostic tool in thoracic tumors during the COVID-19 pandemic
Objective: In this review, we evaluate the role of liquid biopsy in managing lung cancer patients during the
still ongoing coronavirus disease 2019 (COVID-19) healthcare emergency.
Background: The novel influenza coronavirus (severe acute respiratory syndrome coronavirus or SARSCoV-2) has upended several aspects of our lives, including medical activities. In this setting, many routine
cancer diagnostic and therapeutic procedures have been suspended, leading to delays in diagnosis, treatments,
and, ultimately, increases in cancer mortality rates. Equally drastic has been the impact of COVID-19 on
clinical trials, many of which have been stalled or have never begun. This has left many patients who were
hoping to receive innovative treatments in a limbo. Although, as of today, the introduction of drastic security
measures has been crucially important to contain the pandemic, one cannot ignore the need to continue
providing chronically ill patients all the health care they need, in terms of detection, prevention, and
treatment. In these unprecedented times, liquid biopsy, more than ever before, may play a relevant role in
the adequate management of these frail patients.
Methods: we performed a deep analysis of the recent international literature published in English on
PUBMED in the last six months focused on the impact of SARS-CoV-2 on the management of lung cancer
patients, focusing the attention on the role of liquid biopsy.
Conclusions: COVID-19 pandemic has significantly modified our lives and overall medical practice. In
these unprecedented times, liquid biopsy may represent a valid and less time-consuming diagnostic approach
than conventional tissue and cytological specimens
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